cyclin-d1 and Adenoma

In recent years, numerous studies have been performed to investigate the CCND1 G870A gene polymorphism impact on brain tumors susceptibility. Unfortunately, the results of previous studies were inconsistent. Therefore, we performed a meta-analysis to derive a more precise estimation of any association.. We conducted a search in PubMed, Embase and CNKI covering all published papers up to November, 2013. Odds ratios (ORs) and their 95% confidence intervals (95%CIs) were applied to assess associations.. A total of 6 publications including 9 case-control studies met the inclusion criteria. The pooled ORs for the total included studies showed significant association among comparison A vs G (OR= 1.246, 95%CI= 1.092-1.423, p= 0.001), homozygote comparison AA vs GG (OR= 1.566, 95%CI= 1.194-2.054, p= 0.001), heterozygote comparison AG vs GG (OR= 1.290, 95%CI= 0.934-1.782, p= 0.122), dominant model AA/GA vs GG (OR= 1.381, 95%CI= 1.048-1.821, p= 0.022) and recessive model AA vs GA/GG (OR= 1.323, 95%CI= 1.057- 1.657, p= 0.015) especially in glioma.. CCND1 G870A polymorphism may increase brain tumor risk, especially for gliomas. However, more primary large scale and well-designed studies are still required to evaluate the interaction of CCND1 G870A polymorphism with brain tumor risk.

Topics: Adenoma; Brain Neoplasms; Cyclin D1; Genetic Predisposition to Disease; Glioma; Humans; Meningioma; Neuroma, Acoustic; Odds Ratio; Pituitary Neoplasms; Polymorphism, Single Nucleotide

Pituitary cells are particularly sensitive to alterations of the cell cycle machinery. In fact, mutations affecting expression of proteins critical for cell cycle progression, including retinoblastoma protein, cyclins D1 and D3, p16(INK4A), and p27(kip1), are frequent in human pituitary adenomas. Similarly, both targeted disruption and overexpression of either cell cycle inhibitors or activators, respectively, lead to the development of pituitary adenomas in mice. Recent evidence has added the high mobility group A (HMGA) proteins as a new class of cell cycle regulators that play significant roles in the pathways that lead to pituitary tumor evolution in both humans and experimental animal models. Here, we first review the role of the cell cycle in pituitary tumorigenesis, as witnessed by human pathology and transgenic mice; and then, we focus on HMGA proteins and their cell cycle-related role in pituitary tumorigenesis.

Topics: Adenoma; Adult; Animals; Cell Cycle; Cell Cycle Proteins; Cyclin D1; Cyclin D3; Cyclin-Dependent Kinase Inhibitor p16; Cyclin-Dependent Kinase Inhibitor p27; Female; HMGA Proteins; Humans; Male; Mice; Mice, Transgenic; Pituitary Gland; Pituitary Neoplasms; Retinoblastoma Protein; Tumor Suppressor Proteins

Berries contain a number of compounds that are proposed to have anticarcinogenic properties. We wanted to see if pure ellagic acid, natural ellagitannins and three wild berries have any effect on the adenoma formation in Apc- mutated Min/+ mice. Min/+ mice were fed high-fat AIN93-G diets containing 10% (w/w) freeze-dried bilberry (Vaccinium myrtillus), lingonberry (Vaccinium vitis-idaea), cloudberry (Rubus chamaemorus), cloudberry seeds or cloudberry pulp or pure ellagic acid at 1564 mg/kg for 10 weeks. beta-Catenin and cyclin D1 protein levels in the adenomas and in the normal-appearing mucosa were determined by Western blotting and immunohistochemistry. Early changes in gene expression in the normal-appearing mucosa were analyzed by Affymetrix microarrays. Three wild berries significantly reduced tumour number (15-30%, p < 0.05), and cloudberry and lingonberry also reduced tumour size by over 60% (p < 0.01). Cloudberry resulted in decreased levels of nuclear beta-catenin and cyclin D1 and lingonberry in the level of cyclin D1 in the large adenomas (p < 0.05). Affymetrix microarrays revealed changes in genes implicated in colon carcinogenesis, including the decreased expression of the adenosine deaminase, ecto-5f-nucleotidase and PGE2 receptor subtype EP4. Ellagic acid had no effect on the number or size of adenomas in the distal or total small intestine but it increased adenoma size in the duodenum when compared with the control diet (p < 0.05). Neither cloudberry seed nor pulp had any effect on the adenoma formation. Berries seem to have great potential as a source of chemopreventive components.

Topics: Adenoma; Animals; Antineoplastic Agents, Phytogenic; beta Catenin; Cell Transformation, Neoplastic; Cyclin D1; Ellagic Acid; Fruit; Genes, APC; Hydrolyzable Tannins; Intestinal Mucosa; Intestinal Neoplasms; Mice; Mice, Mutant Strains; Random Allocation

To review the evidence implicating the deregulation of cyclin D1 in the pathogenesis of non-small cell lung cancer (NSCLC), and to discuss the opportunities for targeted clinical intervention.. Data published until June 2006 are summarized, and previously unpublished results from our own research are included.. In normal cells, cyclin D1 complexes with and activates cyclin-dependent kinases (CDK) and acts as a transcriptional regulator. The protein is frequently overexpressed in a wide range of cancers, sometimes coincident with CCND1 (cyclin D1) gene amplification (5-20% of tumours). A low level of somatic mutations have been seen in certain tumours. CCND1 is amplified in NSCLC and cyclin D1 is frequently overexpressed in tumours and pre-invasive bronchial lesions, generally from one parental allele. Mutation analyses revealed a frequent CCND1 gene polymorphism (A870G) that modulates alternative splicing and allows expression of an alternative cyclin D1 transcript (transcript cyclin D1b). The encoded cyclin D1b protein lacks a specific phosphorylation site required for nuclear export. Genotype has been correlated with the risk and/or severity of disease or drug response across a range of malignancies, including lung cancer. Together, these findings suggest a strong pathological role for cyclin D1 deregulation in bronchial neoplasia.. Current data indicate that cyclin D1 overexpression is not a consequence of, but rather a pivotal element in the process of malignant transformation in the lung and other tissues. This understanding may open new avenues for lung cancer diagnosis, treatment and prevention.

Topics: Adenoma; Carcinoma, Non-Small-Cell Lung; Cell Transformation, Neoplastic; Cyclin D1; Gene Expression Regulation, Neoplastic; Glioblastoma; Humans; Lung Neoplasms; Polymorphism, Genetic

Primary hyperparathyroidism (pHPT) is a common endocrine disorder that predominantly affects postmenopausal women. It is mostly caused by solitary tumours within the parathyroid glands. Although the pathophysiology of pHPT is still incompletely understood, recent studies provide new clues on the development and cellular growth of tumours within the parathyroids associated with hypersecretion of parathyroid hormone and hypercalcaemia. The natural course of pHPT is rather benign. Nowadays, it has become an oligo- or asymptomatic disease often only detected by routine blood tests. These facts raise the question whether to perform parathyroidectomy on oligo- and asymptomatic patients with pHPT or whether it is possible to monitor these patients without surgery. The aim of this article is to review the literature as regards (i) the pathophysiological mechanisms that underlie parathyroid neoplasia and (ii) the defective calcium-sensing in patients with pHPT (iii) environmental and/or genetic risk factors that predispose to or promote parathyroid neoplasia, as well as (iv) alternative approaches to treat oligo- and asymptomatic patients with pHPT medically.

Topics: Adenoma; Aged; Calcium; Chromosome Aberrations; Cyclin D1; Diphosphonates; Estrogens; Female; Gene Rearrangement; Genetic Predisposition to Disease; Humans; Hyperparathyroidism; Male; Middle Aged; Parathyroid Neoplasms; Proto-Oncogene Proteins; Risk Factors; Selective Estrogen Receptor Modulators

Topics: Adenoma; Animals; Calcium; Cloning, Molecular; Cyclin D1; Humans; Mammary Neoplasms, Animal; Oncogenes; Parathyroid Hormone; Parathyroid Neoplasms

This article will primarily focus on the molecular pathogenesis of common, sporadic (nonfamilial) parathyroid adenomas; two genes currently have established roles in the development of these tumors. The cyclin D1/PRAD1 gene was identified as a clonally activated oncogene in parathyroid adenomas and has subsequently been established as a major contributor to human neoplasia. Overexpression of cyclin D1, a key regulator of the cell cycle, has been implicated in the pathogenesis of 20-40% of sporadic parathyroid adenomas. That such cyclin D1 overexpression indeed constitutes a stimulus to excessive parathyroid cell proliferation has been confirmed experimentally by the development of a transgenic mouse model with parathyroid-targeted overexpression of cyclin D1. Parathyroid hormone (PTH)-cyclin D1 transgenic mice develop parathyroid hypercellularity, biochemical hyperparathyroidism, and a shifted in vivo parathyroid-calcium setpoint; these mice constitute an animal model of human hyperparathyroidism in which aspects of tumorigenesis, parathyroid secretory setpoint control, and the pathophysiology of the chronic hyperparathyroid state can be further investigated. The MEN1 tumor suppressor is the only other gene to date with an established role in the pathogenesis of sporadic parathyroid adenomatosis. Specific clonal alterations involving somatic mutation and/or deletion of both MEN1 alleles have been demonstrated in about 15-20% of sporadic parathyroid adenomas. Allelic losses on 11q occur in roughly twice this number of adenomas, raising the still-unresolved possibility that an additional tumor suppressor gene on 11q may be the functional target of many of these acquired deletions. A mouse model of MEN1 deficiency causes a phenotype that includes parathyroid hypercellularity albeit unaccompanied by biochemical hyperparathyroidism, and additional mouse models in which menin deficiency is targeted to the parathyroids will likely provide additional important insights. The MEN1 gene product menin may have a role in transcriptional regulation involving JunD; several other menin-interacting proteins have also been identified. The in vivo mechanism of menin's actions, with special attention to its role as a parathyroid oncosuppressor, will be important to establish, as will the potential interrelationships between these pathways and those involving cyclin D1. A number of genes, put forth as candidate tumor suppressors based on their genomic locations, roles in fami

Topics: Adenoma; Cyclin D1; Drosophila Proteins; Gene Expression Regulation, Neoplastic; Genes, Tumor Suppressor; Humans; Hyperparathyroidism; Mutation; Neoplasm Proteins; Parathyroid Neoplasms; Proto-Oncogene Proteins; Proto-Oncogene Proteins c-ret; Receptor Protein-Tyrosine Kinases; Receptors, Calcitriol; Receptors, Calcium-Sensing; Receptors, Cell Surface

An important role for beta-catenin pathways in colorectal carcinogenesis was first suggested by the protein's association with adenomatous polyposis coli (APC) protein, and by evidence of dysregulation of beta-catenin protein expression at all stages of the adenoma-carcinoma sequence. Recent studies have, however, shown that yet more components of colorectal carcinogenesis are linked to beta-catenin pathways. Pro-oncogenic factors that also release beta-catenin from the adherens complex and/or encourage translocation to the nucleus include ras, epidermal growth factor (EGF), c-erbB-2, PKC-betaII, MUC1, and PPAR-gamma, whereas anti-oncogenic factors that also inhibit nuclear beta-catenin signaling include transforming growth factor (TGF)-beta, retinoic acid, and vitamin D. Association of nuclear beta-catenin with the T cell factor (TCF)/lymphoid enhancer factor (LEF) family of transcription factors promotes the expression of several compounds that have important roles in the development and progression of colorectal carcinoma, namely: c-myc, cyclin D1, gastrin, cyclooxygenase (COX)-2, matrix metalloproteinase (MMP)-7, urokinase-type plasminogen activator receptor (aPAR), CD44 proteins, and P-glycoprotein. Finally, genetic aberrations of several components of the beta-catenin pathways, eg, Frizzled (Frz), AXIN, and TCF-4, may potentially contribute to colorectal carcinogenesis. In discussing the above interactions, this review demonstrates that beta-catenin represents a key molecule in the development of colorectal carcinoma.

Topics: Adenoma; Adenomatous Polyposis Coli Protein; Animals; ATP Binding Cassette Transporter, Subfamily B, Member 1; beta Catenin; Calcium-Calmodulin-Dependent Protein Kinases; Carcinoma; Colorectal Neoplasms; Cyclin D1; Cyclooxygenase 2; Cytoskeletal Proteins; Gastrins; Glycogen Synthase Kinase 3; Humans; Hyaluronan Receptors; Intestinal Mucosa; Isoenzymes; Matrix Metalloproteinase 7; Membrane Proteins; Prostaglandin-Endoperoxide Synthases; Proto-Oncogene Proteins; Receptors, Cell Surface; Receptors, Urokinase Plasminogen Activator; Signal Transduction; Trans-Activators

Primary hyperparathyroidism (pHPT), generally caused by a monoclonal parathyroid adenoma, is a common endocrinopathy. Until recently, the genesis of the disease was poorly understood but during the past decade the molecular pathology of parathyroid tumor development has begun to be unveiled. This review summarizes recent advances in our understanding of genetic predisposition to pHPT, and the role of vitamin D receptor gene (VDR) variants in development of the disease. It has been shown that the multiple endocrine neoplasia tumor suppressor gene (MEN1) is mutated in parathyroid adenomas, and overexpression of the cyclin D1 oncogene [PRAD1 (parathyroid adenoma 1)] seems to contribute to parathyroid tumorigenesis. Several familial hyperparathyroid disorders have been studied, and the identification and characterization of the disease-causing genes have contributed to our understanding of parathyroid physiology and pathophysiology.

Topics: Adenoma; Cyclin D1; Genetic Predisposition to Disease; Humans; Hyperplasia; Multiple Endocrine Neoplasia Type 1; Mutation; Parathyroid Glands; Parathyroid Neoplasms; Receptors, Calcitriol

Pituitary tumors constitute 10% of intracranial neoplasms and are mostly benign, monoclonal adenomas derived from single mutant cells. Pituitary oncogenes have been intensively studied and three of them, gsp, ccnd1, and PTTG are abundant in significant numbers of cases. gsp is present in approximately 40% of Caucasian patients with GH-secreting tumors and results from a mutated, constitutively active alpha subunit of Gs protein. Persistent activation of the cAMP-PKA-CREB pathway may lead to uncontrolled cell proliferation and GH secretion. ccnd1 is overexpressed cyclin D1, and cyclin D1 gene is amplified in some pituitary tumors. PTTG is expressed in most pituitary tumors. PTTG is localized to both the nucleus and cytoplasm and interacts with several protein partners. At least three tumorigenesis mechanisms are proposed for human PTTG. 1) PTTG and FGF form a positive feedback loop and stimulate tumor vascularity. 2) PTTG transactivates c-myc or other pro-proliferation genes. 3) PTTG overexpression causes aneuploidy. PTTG expression activates p53 and causes p53-dependent and -independent apoptosis. Due to lack of functional human pituitary cell cultures and appropriate animal models for pituitary tumors, many of the results reviewed here are obtained from heterologous systems.

Topics: Adenoma; Animals; Cell Cycle; Cell Division; Cloning, Molecular; Cyclin D1; Gene Expression Regulation, Neoplastic; GTP-Binding Protein alpha Subunits, Gs; Humans; Mice; Mice, Nude; Multigene Family; Neoplasm Proteins; Oncogenes; Organ Specificity; Pituitary Neoplasms; Rats; Securin; Signal Transduction; Species Specificity; Transcriptional Activation; Transfection

Topics: Adenoma; Animals; Chromosomes, Human, Pair 11; Cyclin D1; Cyclins; Gene Amplification; Gene Expression Regulation; Humans; Lymphoma, B-Cell; Neoplasms; Oncogene Proteins; Parathyroid Neoplasms

Two molecular defects have been described in parathyroid adenomas: rearrangement and overexpression of the PRAD1/cyclin D1 oncogene and allelic loss of chromosome 11 DNA, often including the multiple endocrine neoplasia type 1 (MEN1) putative tumor suppressor gene region. In an effort to identify additional parathyroid tumor suppressor genes, we examined 25 parathyroid adenomas for tumor-specific allelic loss of polymorphic DNA loci located near known or candidate tumor suppressor genes. Control leukocyte DNA from all 25 patients was heterozygous for 1 or more of the 9 chromosome 1 markers examined. Allelic loss at 1 or more of these informative loci on chromosome 1 was observed in 10 of 25 (40%) adenomas. Although many tumors lost extensive regions on chromosome 1, all but one of these tumors had allelic loss of distal 1p (1p32-pter); four tumors also lost loci on 1q. Allelic loss at 11q13, the site of the MEN1 gene, was detected in 5 of 21 (24%) informative cases, including 3 with 1p loss. In contrast, allelic loss was rarely observed at loci on 9q and 10p and was not observed at loci on 3p, 3q, 4p, 5q, 12q, 14q, 18q, 22q, or Xp. In summary, clonal allelic loss of loci on chromosome arm 1p is a frequent feature of parathyroid adenomas, implying that inactivation of a tumor suppressor gene(s) on 1p commonly contributes to their pathogenesis.

Topics: Adenoma; Adolescent; Adult; Aged; Alleles; Chromosomes, Human, Pair 1; Cyclin D1; Cyclins; DNA; DNA, Neoplasm; Female; Follow-Up Studies; Gene Deletion; Gene Expression Regulation, Neoplastic; Gene Rearrangement; Genetic Markers; Heterozygote; Humans; Male; Middle Aged; Oncogene Proteins; Parathyroid Neoplasms; Transcriptional Activation

Topics: Adenoma; Chromosome Inversion; Chromosomes, Human, Pair 11; Cyclin D1; Cyclins; Gene Expression Regulation, Neoplastic; Gene Rearrangement; Genes, Retinoblastoma; Humans; Oncogene Proteins; Parathyroid Neoplasms; Proto-Oncogene Proteins

The D-type cyclins are among the candidate 'G1 cyclins' in higher eukaryotes that may regulate G1-S-phase progression. The human cyclin D1 gene, also known as PRAD1 (and previously as D11S287), is a putative proto-oncogene strongly implicated in several types of human tumors, including parathyroid adenomas, B-cell neoplasms (as the 'BCL-1 oncogene'), and breast and squamous cell cancers. The mechanism by which deregulated production of cyclin D1/PRAD1, and perhaps other D-type cyclins, contributes to tumor development is only beginning to be deciphered.

Topics: Adenoma; Breast Neoplasms; Carcinoma, Squamous Cell; Cell Cycle; Cell Division; Cell Transformation, Neoplastic; Cyclin D1; Cyclins; Gene Expression Regulation, Neoplastic; Humans; Leukemia, B-Cell; Lymphoma, B-Cell; Multigene Family; Oncogene Proteins; Parathyroid Neoplasms; Proto-Oncogene Mas; Proto-Oncogenes

Low-dose aspirin reduces the incidence of colorectal cancer and recurrence of adenomas. Cyclooxygenase-2 (COX-2), one of its main target enzymes, is reportedly over-expressed in colorectal adenomas.. To assess COX-2 expression, in relation to adenoma recurrence and the protective effect of aspirin, in a large series of colorectal adenomas, recruited from a double-blind randomised controlled trial comparing recurrences after low-dose aspirin or placebo.. Follow-up colonoscopies were performed after 1 and 4 years to assess adenoma recurrence. COX-2 expression was assessed by immunohistochemistry for each adenoma obtained at baseline colonoscopy, separately for epithelium, deep stroma and overall. Architecture, grade of dysplasia, K-ras mutation, p53 and cyclin D1 expression were studied.. COX-2 expression could be assessed in 219 adenomas from 136. 128 adenomas (58%) from 59 patients strongly expressed COX-2. Strong COX-2 expression predominated in adenomas larger than 10 mm (84/129 vs 44/90; p=0.02) and in adenomas showing high-grade dysplasia (22/29 vs 104/188; p=0.04). Deep stromal but not epithelial initial expression of COX-2 predicted adenoma recurrence in the whole population (30/72 patients or 42% strongly expressed deep stromal COX-2 compared with 16/64 or 25% without recurrent adenoma; p=0.04). The protective effect of aspirin was mainly observed in patients in whom COX-2 initial expression was low (RR for recurrence in patients taking aspirin with low COX-2 expression: 0.59; 95% CI 0.39 to 0.90; p=0.02). There was no significant effect of aspirin at the end of the trial.. Over-expression of COX-2 was frequent and predominated in large and high-grade dysplasia adenomas. Deep stromal but not epithelial initial expression of COX-2 predicted recurrence of adenomas. Aspirin did not act preferentially on patients whose initial adenomas strongly expressed COX-2.

Topics: Adenoma; Adolescent; Adult; Aged; Anticarcinogenic Agents; Aspirin; Biomarkers, Tumor; Colorectal Neoplasms; Cyclin D1; Cyclooxygenase 2; Cyclooxygenase Inhibitors; Double-Blind Method; Female; Genes, ras; Humans; Male; Middle Aged; Mutation; Neoplasm Proteins; Neoplasm Recurrence, Local; Tumor Suppressor Protein p53; Young Adult

With the continuous discovery of new borderline thyroid lesions and benign and malignant "gray areas", coupled with the limitations of traditional immune indicators, the differential diagnosis of papillary thyroid carcinoma (PTC) has become more difficult. Cyclin D1 and P21 are cell cycle regulators involved in the occurrence and metastasis of multiple tumors, including PTC, but their specific functions are unclear.. In our study, immunohistochemical staining was used to explore the expression of Cyclin D1 and P21 in PTC, paracancerous tissue, follicular adenoma (FA) and papillary thyroid hyperplasia. In addition, their relationship with the clinicopathological features of PTC and their differential diagnostic value in distinguishing between intralymph node PTC metastases and intralymph node ectopic thyroid tissue were studied.. Among 200 primary PTC lesions, Cyclin D1 and P21 were found to be expressed in 186 (93.00%) and 177 (88.50%), respectively, and their expression levels were significantly higher in PTC tissue than in adjacent tissue, FA tissue and papillary thyroid hyperplasia tissue (P < 0.05). The expression levels of Cyclin D1 and P21 were positively correlated with tumor size and lymph node metastasis (P < 0.05) but not with sex, age, number of tumor lesions, histological subtype, chronic lymphocytic thyroiditis or TNM stage (P < 0.05). The expression levels of Cyclin D1 and P21 were significantly correlated (P < 0.05). The positivity rates of Cyclin D1 and P21 in intralymph node PTC metastases were 97.96% (48/49) and 89.80% (44/49), respectively, which were significantly higher than those in intralymph node ectopic thyroid tissue (P < 0.05). The sensitivity (Se) and negative predictive value (NPV) of Cyclin D1 and P21 detection alone or in combination were higher than those of the combined detection of the classical antibody markers CK19, HBME-1 and Galectin-3. Besides, the Se, Sp, PPV and NPV of Cyclin D1 and P21 in differentiating intralymph node PTC metastases and intralymph node ectopic thyroid tissue were higher.. The results of our study show that Cyclin D1 and P21 are highly sensitive and specific markers for the diagnosis of PTC that are superior to traditional classical antibodies. And, these two markers are of great value in the differential diagnosis of intralymph node PTC metastases and intralymph node ectopic thyroid tissue.

Topics: Adenoma; Biomarkers, Tumor; Carcinoma, Papillary; Cyclin D1; Diagnosis, Differential; Humans; Hyperplasia; Thyroid Cancer, Papillary; Thyroid Dysgenesis; Thyroid Neoplasms

Cancer is one of the biggest health problems in the world. Colon adenocarcinoma is the third most common cancer and is the fourth most common cause of cancer deaths. The majority of colon adenocarcinomas originate from a previous adenoma. Cyclin D1 expression and Ki-67 proliferation index increase as the risk of malignancy transformation increases in adenomas.. This study aims to share the results of the Cyclin D1 and Ki-67 studies we performed in colon adenoma and colon adenocarcinoma cases in our hospital with the literature and contribute to the diagnosis and treatment of patients.. Surgical materials of 40 colon adenocarcinomas and 40 colon adenomas were histopathologically re-evaluated. Cyclin D1 and Ki-67 immunohistochemical staining were applied to these materials. Cyclin D1 and Ki-67 staining rates were compared in colon adenocarcinomas and adenomas.. Cyclin D1 and Ki-67 staining rates were increased in colon adenocarcinoma cases compared to colon adenoma. There was a significant difference between the colon adenocarcinoma and colon adenoma case groups in terms of Cyclin D1 and Ki-67 staining scores.. In conclusion, immunohistochemical markers such as Cyclin D1 and Ki-67 will be helpful in differential diagnosis when there is difficulty in evaluating routine Hematoxylin-Eosin stained preparations between adenocarcinomas and adenomas.

Topics: Adenocarcinoma; Adenoma; Colon; Cyclin D1; Humans; Ki-67 Antigen

The crypt-villus axis represents the essential unit of the small intestine, which integrity and functions are fundamental to assure tissue and whole-body homeostasis. Disruption of pathways regulating the fine balance between proliferation and differentiation results in diseases development. Nowadays, it is well established that microRNAs (miRNAs) play a crucial role in the homeostasis maintenance and perturbation of their levels may promote tumor development. Here, by using microarray technology, we analysed the miRNAs differentially expressed between the crypt and the villus in mice ileum. The emerged miRNAs were further validated by Real Time qPCR in mouse model (ApcMin/+), human cell lines and human tissue samples (FAP) of colorectal cancer (CRC). Our results indicated that miRNAs more expressed in the villi compartment are negatively regulated in tumor specimens, thus suggesting a close association between these microRNAs and the differentiation process. Particularly, from our analysis let-7e appeared to be a promising target for possible future therapies and a valuable marker for tumor staging, being upregulated in differentiated cells and downregulated in early-stage colonic adenoma samples.

Topics: Adenoma; Adenomatous Polyposis Coli; Adenomatous Polyposis Coli Protein; Animals; Cell Line, Tumor; Colorectal Neoplasms; Cyclin D1; Down-Regulation; Humans; Male; Mice; Mice, Inbred C57BL; Mice, Transgenic; MicroRNAs; Proto-Oncogene Proteins c-myc

The protein product of the cyclin D1 oncogene functions by activating partner cyclin-dependent kinases (cdk)4 or cdk6 to phosphorylate, thereby inactivating, the retinoblastoma protein pRB. Nonclassical, cdk-independent, functions of cyclin D1 have been described but their role in cyclin D1-driven neoplasia, with attendant implications for recently approved cdk4/6 chemotherapeutic inhibitors, requires further examination. We investigated whether cyclin D1's role in parathyroid tumorigenesis in vivo is effected primarily through kinase-dependent or kinase-independent mechanisms. Using a mouse model of cyclin D1-driven parathyroid tumorigenesis (PTH-D1), we generated new transgenic lines harboring a mutant cyclin D1 (KE) that is unable to activate its partner kinases. While this kinase-dead KE mutant effectively drove mammary tumorigenesis in an analogous model, parathyroid-overexpressed cyclin D1 KE mice did not develop the characteristic biochemical hyperparathyroidism or parathyroid hypercellularity of PTH-D1 mice. These results strongly suggest that in parathyroid cells, cyclin D1 drives tumorigenesis predominantly through cdk-dependent mechanisms, in marked contrast with the cdk-independence of cyclin D1-driven mouse mammary cancer. These findings highlight crucial tissue-specific mechanistic differences in cyclin D1-driven tumorigenesis, suggest that parathyroid/endocrine cells may be more tumorigenically vulnerable to acquired genetic perturbations in cdk-mediated proliferative control than other tissues, and carry important considerations for therapeutic intervention.

Topics: Adenoma; Animals; Cell Transformation, Neoplastic; Cyclin D1; Cyclin-Dependent Kinase 4; Cyclin-Dependent Kinase 6; Hyperparathyroidism; Mice; Mice, Transgenic; Mutation; Parathyroid Neoplasms; Phosphorylation; Signal Transduction

Background and study aim: Cyclin D1 is a key regulatory protein in the cell cycle and is over-expressed in\ many tumors, including endometrial, thyroid, urothelial, breast, brain gliomas, and esophageal cancers. The main\ aim of the present study is to examine the expression pattern of cyclin D1 and its correlation with the different\ clinicopathological features in patients with colorectal camcer (CRC) from the Madinah region of Saudi Arabia.\ Patients and methods: The archival tumor blocks were analyzed using immunohistochemistry for Cyclin D1\ over-expression in 324 CRC patients diagnosed from January 2006 to December 2017, at the Department of Pathology,\ King Fahad Hospital, Madinah, Saudi Arabia. Results: Cyclin D1 over-expression was absent in normal mucosa, while\ 15% cases of adenoma showed its over-expression. In CRC, Cyclin D1 was expressed at high levels in 24.1% of case.\ No significant correlation was observed between Cyclin D1 over-expression and age, gender, tumor size, type and\ location. However, Cyclin D1 over-expression exhibited a significant correlation with tumor differentiation (p=0.04),\ lymph node involvement (p=0.001), lymphovascular invasion (p=0.001), distant metastasis (p=0.006) and AJCC staging\ (p=0.001). The Kaplan-Meir analysis revealed a shorter period of survival with Cyclin D1 over-expression (p=0.000).\ The Cox-regression model analysis showed that Cyclin D1 over-expression was an independent prognostic marker\ in CRC (p=0.000). Conclusion: Cyclin D1 over-expression increases during normal-adenoma-carcinoma sequence.\ The significant association observed between Cyclin D1 over-expression, advanced tumor stage and short survival\ period clearly suggest the role of Cyclin D1 in the carcinogenesis and progression of CRC.

Topics: Adenoma; Adult; Aged; Aged, 80 and over; Biomarkers, Tumor; Case-Control Studies; Colorectal Neoplasms; Cyclin D1; Female; Follow-Up Studies; Humans; Lymphatic Metastasis; Male; Middle Aged; Neoplasm Invasiveness; Prognosis; Retrospective Studies; Saudi Arabia; Survival Rate; Young Adult

BACKGROUND As a kind of benign tumor, pituitary adenomas have attracted increasing attention from researchers. The plasmacytoma variant translocation 1 (PVT1) is a molecule in the lncRNA family protein that has been proven to play critical roles in many cancers; however, no study has explored the special biological roles of PVT1 in pituitary adenoma. MATERIAL AND METHODS The qRT-PCR assay was conducted to evaluate PVT1 expressions in various cell lines and tissues. Loss of function assays were carried out to detect the influence of silenced PVT1 on the proliferation, migration, and epithelial-mesenchymal transition (EMT) of pituitary adenoma cells. Western blotting was used to identify correlation between ß-catenin and PVT1. RESULTS The PVT1 expressions were significantly enhanced in tissues of pituitary adenoma and cancer cells. Cell migration and proliferation were inhibited when the PVT1 gene was knocked down. Knockdown of PVT1 repressed the migration and EMT of pituitary adenoma cells. The PVT1 downregulation obviously blocked Wnt/ß-catenin signaling pathway activity. PVT1 aggravated progression of pituitary adenoma through initiating the Wnt/ß-catenin signaling pathway. CONCLUSIONS PVT1 exerts an oncogenic role through activating Wnt/ß-catenin signaling in pituitary adenoma cells. The present results may provide a potential therapeutic target or approach for treating pituitary adenomas.

Topics: Adenoma; beta Catenin; Biomarkers, Tumor; Cell Line, Tumor; Cell Movement; Cell Proliferation; Cyclin D1; Epithelial-Mesenchymal Transition; Gene Expression Regulation, Neoplastic; Humans; Pituitary Neoplasms; Proto-Oncogene Proteins c-myc; RNA, Long Noncoding; RNA, Small Interfering; Wnt Signaling Pathway

The molecular mechanisms underlying tumor growth in Cushing's disease (CD) still remain a challenge. Moreover, clinical manifestations of CD may vary depending on hormonal activity; however, factors involved in the hormonal aggressiveness of adrenocorticotropic hormone (ACTH)-secreting pituitary tumors have not been fully clarified. We investigated the association between the expression of cellular markers regarding pituitary tumor progression and initial or postoperative hormone levels in patients with CD.. Tumor tissues from 28 corticotroph adenomas (female 26, male 2, mean age 39.21 ± 10.39 years) were subject to immunohistochemical study using the following antibodies: pituitary tumor-transforming gene 1 (PTTG1), cyclin D1, p16, p27, brahma related-gene 1 (Brg1), and Ki-67. We then analyzed the relationship between each cellular marker expression and hormone levels, including 24 h urinary free cortisol (UFC), plasma ACTH, and serum cortisol.. PTTG1 and Ki-67 were expressed in 100% and 50% of patients, respectively. However, the levels did not reflect initial hormonal activity. The cyclin D1-negative group showed higher serum cortisol levels compared to the cyclin D1-positive group (p = 0.01). The 24 h UFC levels were significantly higher in the p27-negative group than in the p27-positive group (p = 0.04), whereas the Brg1-positive group revealed higher serum cortisol levels than in the Brg1-negative group (p = 0.02).. Although PTTG1 and Ki-67 play an essential role in developing ACTH-secreting tumors, cyclin D1, p27, and Brg1 may be better biomarkers to determine hormonal aggressiveness of the tumor. Further research is needed to understand the influence of cellular markers on hormonal activity in CD.

Topics: ACTH-Secreting Pituitary Adenoma; Adenoma; Adolescent; Adrenocorticotropic Hormone; Adult; Aged; Cyclin D1; Cyclin-Dependent Kinase Inhibitor p16; DNA Helicases; Female; Humans; Hydrocortisone; Immunohistochemistry; Male; Middle Aged; Nuclear Proteins; Pituitary Gland; Securin; Transcription Factors; Young Adult

Widespread use of high-resolution imaging techniques and thus increased prevalence of adrenal lesions has made diagnostics of adrenocortical tumours an increasingly important clinical issue. In non-metastatic tumours, diagnosis is based on histology. New or enhanced information for clinicopathological diagnosis, revealing the malignant potential of the tumour, could emerge by means of biomarkers. The connection of proto-oncogene c-myc to adrenocortical neoplasias is poorly known, although the Wnt/beta-catenin pathway, one of the signalling pathways leading to induction of c-myc expression, has been connected to development of adrenocortical neoplasias. We studied c-myc expression in adrenocortical tumours and investigated molecules associated with the signalling pathway of c-myc, including cell cycle-related proteins p27, cyclin E and cyclin D1.. We studied 195 consecutive adult patients with 197 primary adrenocortical tumours. Histopathological diagnosis was determined by Weiss score and the novel Helsinki score. C-myc, cyclin D1, cyclin E and p27 expressions were determined by immunohistochemistry.. Benign adenomas showed prominent nuclear c-myc expression comparable to that of normal adrenocortical cells, whereas carcinomas showed increased cytoplasmic expression. Strong cytoplasmic and weak nuclear c-myc expressions associated with malignancy and adverse outcome. C-myc staining did not correlate with cyclin E. Cyclin D1 correlated with cytoplasmic c-myc expression and to a lesser extent with nuclear c-myc. P27 correlated with cytoplasmic c-myc, but not with nuclear c-myc. P27 correlated with cyclin E.. Strong cytoplasmic c-myc expression and weak nuclear expression in adrenocortical tumours associated with malignancy and shorter survival.

Topics: Adenoma; Adrenal Cortex Neoplasms; Adult; Aged; Aged, 80 and over; Biomarkers, Tumor; Carcinoma; Cyclin D1; Cyclin E; Female; Follow-Up Studies; Humans; Male; Middle Aged; Prognosis; Proliferating Cell Nuclear Antigen; Proto-Oncogene Mas; Proto-Oncogene Proteins c-myc; Signal Transduction; Survival Analysis

Insulin receptor substrate 4 (IRS-4) is an adaptor protein for which new evidence suggests plays a role in tumour promotion.. We described nuclear IRS-4 in RKO colon cancer cell lines in biopsies of patients with colorectal cancer (CRC) (n = 20) and in matched adjacent normal colorectal (MANC) tissue (n = 20).. Treatment with physiological doses of IGF-1 promoted nuclear influx of IRS-4 from cellular cytosol in RKO cells. When exogenous IRS-4 was overexpressed in RKO cells, there was an increase in cyclin D1, cyclin E, E2F1, pRB Ser 809/811 and pRB Ser 705 levels compared with the empty vector-transfected cells. Some of these changes returned to control values after wortmannin treatment. Subcellular fractionation showed an overexpression of IRS-4 in the cytoplasm, membrane, and nuclei of tumour samples, whereas the levels of the protein were barely detectable in the three compartments of normal samples. Immunohistochemical studies showed positive nuclear IRS-4 staining in over 74% of the tumour cells. IRS-4 was strongly overexpressed in tumoural tissues from CRC patients compared to MANC tissues. The up-regulation of IRS-4 in CRC samples correlated significantly with the increase of several G1 checkpoint proteins including cyclin D1 (r = 0.6662), Rb (r = 0.7779), pRb Serine 809/811 (r = 0.6864), pRb serine 705 (r = 0.6261) and E2F1 (r = 0.8702).. Taken together, our findings suggest that IRS-4 promotes retinoblastoma-cyclin-dependent kinase activation and it may serve as a pharmacological target since its expression is very low in normal tissue, including colonic epithelium.

Topics: Adenocarcinoma; Adenoma; Aged; Aged, 80 and over; Carcinoma, Hepatocellular; Cell Line, Tumor; Cell Membrane; Cell Nucleus; Cell Proliferation; Colon; Colorectal Neoplasms; Cyclin D1; Cytoplasm; E2F1 Transcription Factor; Female; Humans; Insulin Receptor Substrate Proteins; Insulin-Like Growth Factor I; Liver Neoplasms; Male; Middle Aged; Neoplasm Grading; Neoplasm Staging; Proliferating Cell Nuclear Antigen; Protein Transport; Rectum; Retinoblastoma Protein; Signal Transduction; Up-Regulation

Primary hyperparathyroidism is commonly caused by excess production of parathyroid hormone from sporadic parathyroid adenomas. However, the genetic architecture of sporadic primary hyperparathyroidism remains largely uncharacterized, especially in the Chinese population. To identify genetic abnormalities that may be involved in the etiology of sporadic parathyroid adenomas and to determine the mutation frequency of previously identified genes in the Chinese population, we performed whole-exome sequencing of 22 blood-tumor pairs from sporadic parathyroid adenomas. The most important finding is the recurrently mutated gene, ASXL3, which has never been reported in parathyroid tumors before. Moreover, we identified two different somatic mutations in the CDC73 gene and one somatic mutation in the EZH2 gene. The Y54X mutation in the CDC73 gene was previously identified in parathyroid carcinomas, which proved that parathyroid adenomas and carcinomas might possess similar molecular signatures. No mutations in the MEN1 or CCND1 genes were observed in our study. Thus, our data provide insights into the genetic pathogenesis of sporadic parathyroid adenomas and are valuable for the development of diagnostic and therapeutic approaches for sporadic primary hyperparathyroidism.

Topics: Adenoma; Adult; Aged; Asian People; Cyclin D1; DNA Mutational Analysis; Enhancer of Zeste Homolog 2 Protein; Exome Sequencing; Female; Humans; Hyperparathyroidism, Primary; Male; Middle Aged; Mutation; Parathyroid Neoplasms; Proto-Oncogene Proteins; Sequence Analysis, DNA; Transcription Factors; Tumor Suppressor Proteins

The canonical Wnt signaling pathway activates the transcriptional activity of β-catenin. This pathway is often activated in colorectal cancer cells, but strategies to block it in tumors have not been effective. The SAM pointed domain containing ETS transcription factor (SPDEF) suppresses formation of colon tumors by unclear mechanisms. We investigated these mechanisms and the effects of SPDEF on β-catenin activity in mouse models of colorectal cancer (CRC), CRC cell lines, and mouse and human normal and cancer colonoids.. We performed studies of Lgr5. Expression of SPDEF was sufficient to inhibit intestinal tumorigenesis by activated β-catenin, block tumor cell proliferation, and restrict growth of established tumors. In tumor cells with activated β -catenin, expression of SPDEF induced a quiescent state, which was reversed when SPDEF expression was stopped. In mouse and human normal and tumor-derived enteroids/colonoids, those that expressed SPDEF for 3 days were significantly smaller. SPDEF inhibited the transcriptional activity of β-catenin via a protein-protein interaction, independent of SPDEF DNA binding capacity. SPDEF disrupted β-catenin binding to TCF1 and TCF3, displacing β-catenin from enhancer regions of genes that regulate the cell cycle but not genes that regulate stem cell activities.. In studies of mice and human CRC, we found that SPDEF induces a quiescent state in CRC cells by disrupting binding of β-catenin to TCF1 and TCF3 and regulation of genes that control the cell cycle. In this model, β-catenin activity determines the proliferation or quiescence of CRC cells based on the absence or presence of SPDEF.

Topics: Adenoma; Animals; Axin Protein; beta Catenin; Carcinogenesis; Cell Cycle; Cell Proliferation; Chromatin; Colon; Colorectal Neoplasms; Cyclin D1; Gene Expression Regulation, Neoplastic; HCT116 Cells; HEK293 Cells; Humans; Hyaluronan Receptors; Intestinal Mucosa; Lymphoid Enhancer-Binding Factor 1; Male; Mice; Organoids; Promoter Regions, Genetic; Proto-Oncogene Proteins c-ets; Proto-Oncogene Proteins c-myc; Receptor, EphB2; Stem Cells; TCF Transcription Factors; Transcription, Genetic; Transfection; Wnt Signaling Pathway

Cyclin D1, a G1-S phase regulator, is upregulated in parathyroid adenomas. Since cyclin-dependent kinase (CDK) inhibitors, CDKN2A and CDKN2B, and RASSF1A (Ras-association domain family 1, isoform A) are involved in G1-S phase arrest and act as potential tumor suppressor genes, we aimed to study potential methylation-mediated inactivation of these genes in parathyroid adenomas. Gene expressions of cyclin D1 (CCND1) and regulatory molecules (CDKN2A, CDKN2B and RASSF1A) was analysed in parathyroid adenoma tissues (n = 30). DNA promoter methylation of cyclin D1 regulators were assessed and correlated with clinicopathological features of the patients. Gene expression analysis showed a relative fold reductions of 0.35 for CDKN2A (p = 0.01), 0.45 for CDKN2B (P = 0.02), and 0.39 for RASSF1A (p < 0.01) in adenomatous compared to normal parathyroid tissue. There was an inverse relationship between the expressions of CDKN2A and CDKN2B with CCND1. In addition, the promoter regions of CDKN2A, CDKN2B, and of RASSF1A were significantly hyper-methylated in 50% (n = 15), 47% (n = 14), and 90% (n = 27) of adenomas respectively. In contrast, no such aberrant methylation of these genes was observed in normal parathyroid tissue. So, promoter hypermethylation is associated with down-regulation of CCND1 regulatory genes in sporadic parathyroid adenomas. This dysregulated cell cycle mechanism may contribute to parathyroid tumorigenesis.

Topics: Adenoma; Adolescent; Adult; Cyclin D1; Cyclin-Dependent Kinase Inhibitor p15; Cyclin-Dependent Kinase Inhibitor p16; Cyclin-Dependent Kinase Inhibitor p18; DNA Methylation; Down-Regulation; Epigenesis, Genetic; Female; Gene Expression Profiling; Gene Expression Regulation, Neoplastic; Humans; Male; Middle Aged; Parathyroid Neoplasms; Promoter Regions, Genetic; Sequence Analysis, DNA; Tumor Suppressor Proteins; Young Adult

CDC73/Parafibromin is a critical component of the Paf1 complex (PAF1C), which is involved in transcriptional elongation and histone modifications. Mutations of the human CDC73/HRPT2 gene are associated with hyperparathyroidism-jaw tumor (HPT-JT) syndrome, an autosomal dominant disorder. CDC73/parafibromin was initially recognized as a tumor suppressor by inhibiting cell proliferation via repression of cyclin D1 and c-myc genes. In recent years, it has also shown oncogenic features by activating the canonical Wnt/β-catenin signal pathway. Here, through limited proteolysis analysis, we demonstrate that the evolutionarily conserved human CDC73 N-terminal 111 residues form a globularly folded domain (hCDC73-NTD). We have determined a crystal structure of hCDC73-NTD at 1.02 Å resolution, which reveals a novel protein fold. CDC73-NTD contains an extended hydrophobic groove on its surface that may be important for its function. Most pathogenic CDC73 missense mutations associated with the HPT-JT syndrome are located in the region encoding CDC73-NTD. Our crystal and biochemical data indicate that most CDC73 missense mutations disrupt the folding of the hydrophobic core of hCDC73-NTD, while others such as the K34Q mutant reduce its thermostability. Overall, our results provide a solid structural basis for understanding the structure and function of CDC73 and its association with the HPT-JT syndrome and other diseases.

Topics: Adenoma; Cell Proliferation; Crystallography, X-Ray; Cyclin D1; Fibroma; Humans; Hydrophobic and Hydrophilic Interactions; Hyperparathyroidism; Jaw Neoplasms; Mutation, Missense; Protein Conformation; Protein Domains; Protein Folding; Proto-Oncogene Proteins c-myc; Surface Properties; Tumor Suppressor Proteins

Intervention strategies in familial adenomatous polyposis (FAP) patients and other high-risk colorectal cancer (CRC) populations have highlighted a critical need for endoscopy combined with safe and effective preventive agents. We performed transcriptome profiling of colorectal adenomas from FAP patients and the polyposis in rat colon (Pirc) preclinical model, and prioritized molecular targets for prevention studies in vivo. At clinically relevant doses in the Pirc model, the drug Clotam (tolfenamic acid, TA) was highly effective at suppressing tumorigenesis both in the colon and in the small intestine, when administered alone or in combination with Sulindac. Cell proliferation in the colonic crypts was reduced significantly by TA, coincident with increased cleaved caspase-3 and decreased Survivin, β-catenin, cyclin D1 and matrix metalloproteinase 7. From the list of differentially expressed genes prioritized by transcriptome profiling, Mmp7, S100a9, Nppb and Aldh1a3 were defined as key oncogene candidates downregulated in colon tumors after TA treatment. Monthly colonoscopies revealed the rapid onset of tumor suppression by TA in the Pirc model, and the temporal changes in Mmp7, S100a9, Nppb and Aldh1a3, highlighting their value as potential early biomarkers for prevention in the clinical setting. We conclude that TA, an "old drug" repurposed from migraine, offers an exciting new therapeutic avenue in FAP and other high-risk CRC patient populations.

Topics: Adenoma; Adenomatous Polyposis Coli; Aldehyde Oxidoreductases; Animals; beta Catenin; Biomarkers, Tumor; Calgranulin B; Carcinogenesis; Caspase 3; Cell Proliferation; Colorectal Neoplasms; Cyclin D1; Down-Regulation; Gene Expression Profiling; Humans; Male; Matrix Metalloproteinase 7; Oncogenes; ortho-Aminobenzoates; Rats

Cushing's disease is caused by pituitary corticotroph adenoma, and the pathogenesis of it has remained obscure. Here, we showed that cold inducible RNA binding protein (CIRP) was markedly elevated in corticotroph tumors. Forced overexpression of CIRP in murine AtT20 pituitary corticotroph cell line increased corticotroph precursor hormone proopiomelanocortin (POMC) transcription, ACTH secretion and cellular proliferation. In vivo, CIRP overexpression promotes murine corticotroph tumor growth and enhances ACTH production. Mechanistically, we show that CIRP could promote AtT20 cells proliferation by inducing cyclinD1 and decreasing p27 expression via Erk1/2 signaling pathway. Clinically, CIRP overexpression is significantly correlated with Cushing's disease recurrence. CIRP appears to play a critical tumorigenesis function in Cushing's disease and its expression might be a useful biomarker for tumor recurrence.

Topics: ACTH-Secreting Pituitary Adenoma; Adenoma; Adrenocorticotropic Hormone; Adult; Aged; Animals; Biomarkers, Tumor; Cell Line, Tumor; Cell Proliferation; Corticotrophs; Cyclin D1; Extracellular Signal-Regulated MAP Kinases; Female; Humans; Male; MAP Kinase Signaling System; Mice; Mice, Nude; Middle Aged; Pituitary ACTH Hypersecretion; Pro-Opiomelanocortin; Proliferating Cell Nuclear Antigen; RNA-Binding Proteins; Young Adult

NHERF1/EBP50, an adaptor molecule that interacts with β-catenin, YAP, and PTEN, has been recently implicated in the progression of various human malignancies, including colorectal cancer. We report here that NHERF1 acts as a tumor suppressor in vivo for intestinal adenoma development. NHERF1 is highly expressed at the apical membrane of mucosa intestinal epithelial cells (IECs) and serosa mesothelial cells. NHERF1-deficient mice show overall longer small intestine and colon that most likely could be attributed to a combination of defects, including altered apical brush border of absorbtive IECs and increased number of secretory IECs. NHERF1 deficiency in Apc(Min/+) mice resulted in significantly shorter animal survival due to markedly increased tumor burden. This resulted from a moderate increase of the overall tumor density, more pronounced in females than males, and a massive increase in the number of large adenomas in both genders. The analysis of possible pathways controlling tumor size showed upregulation of Wnt-β-catenin pathway, higher expression of unphosphorylated YAP, and prominent nuclear expression of cyclin D1 in NHERF1-deficient tumors. Similar YAP changes, with relative decrease of phosphorylated YAP and increase of nuclear YAP expression, were observed as early as the adenoma stages in the progression of human colorectal cancer. This study discusses a complex role of NHERF1 for intestinal morphology and presents indisputable evidence for its in vivo tumor suppressor function upstream of Wnt-β-catenin and Hippo-YAP pathways.

Topics: Adaptor Proteins, Signal Transducing; Adenoma; Animals; beta Catenin; Carcinoma; Cell Cycle Proteins; Cell Transformation, Neoplastic; Colorectal Neoplasms; Cyclin D1; Genes, APC; Humans; Intestinal Mucosa; Mice; Mice, Knockout; Mutation; Phosphoproteins; Phosphorylation; Sodium-Hydrogen Exchangers; Tumor Burden; Wnt Proteins; Wnt Signaling Pathway; YAP-Signaling Proteins

Topics: Adenocarcinoma; Adenoma; beta Catenin; Biomarkers, Tumor; Cancer-Associated Fibroblasts; Carcinogenesis; Colorectal Neoplasms; Cyclin D1; Disease Progression; Humans; Immunohistochemistry; Ki-67 Antigen; Neoplasm Grading; Neoplasm Recurrence, Local; Neprilysin; Predictive Value of Tests; Tumor Suppressor Protein p53

Primary hyperparathyroidism is primarily due to a solitary parathyroid adenoma but multi-gland disease, parathyroid carcinoma, and ectopic parathyroid hormone production can occur. Although primary hyperparathyroidism mostly presents sporadically, strong familial predispositions also exist. Much is known about heritable genetic mutations responsible for these syndromes, including multiple endocrine neoplasia types 1 and 2A, hyperparathyroidism-jaw tumor syndrome, and familial hypocalciuric hypercalcemia. Acquired mutations in common sporadic hyperparathyroidism have also been discovered. Here we focus on the most common and well-established genetic drivers: 1) involvement of the oncogene cyclin D1 in human neoplasia was first established in parathyroid adenomas, followed by recognition of its importance in other tumor types including breast cancer and B-lymphoid malignancy; and 2) somatic mutation of the

Topics: Adenoma; Cyclin D1; Fibroma; Humans; Hyperparathyroidism; Hyperparathyroidism, Primary; Jaw Neoplasms; Parathyroid Neoplasms; Proto-Oncogene Proteins

SWI/SNF chromatin remodeling complexes constitute a highly related family of multi-subunit complexes to modulate transcription, and SWI/SNF subunit genes are collectively mutated in 20% of all human cancers. Bcl11b is a SWI/SNF subunit and acts as a haploinsufficient tumor suppressor in leukemia/lymphomas. Here, we show expression of Bcl11b in intestinal crypt cells and promotion of intestinal tumorigenesis by Bcl11b attenuation in Apc (min/+) mice. Of importance, mutations or allelic loss of BCL11B was detected in one-third of human colon cancers. We also show that attenuated Bcl11b activity in the crypt base columnar (CBC) cells expressing the Lgr5 stem cell marker enhanced regeneration of intestinal epithelial cells after the radiation-induced injury. Interestingly, BCL11B introduction in human cell lines downregulated transcription of β-catenin target genes, whereas Bcl11b attenuation in Lgr5(+) CBCs increased expression of β-catenin targets including c-Myc and cyclin D1. Together, our results argue that Bcl11b impairment promotes tumor development in mouse and human intestine at least in part through deregulation of β-catenin pathway.

Topics: Adenoma; Animals; beta Catenin; Caco-2 Cells; Cell Line, Tumor; Cell Proliferation; Cell Transformation, Neoplastic; Chromosomal Proteins, Non-Histone; Colonic Neoplasms; Cyclin D1; HCT116 Cells; HEK293 Cells; Humans; Intestinal Mucosa; Mice; Mice, Inbred C57BL; Mice, Knockout; Polymorphism, Single Nucleotide; Proto-Oncogene Proteins c-myc; Receptors, G-Protein-Coupled; Repressor Proteins; Transcription Factors; Tumor Suppressor Proteins; Wnt Proteins; Wnt Signaling Pathway

Encapsulated follicular tumours with equivocal papillary thyroid carcinoma (PTC) type nuclear features continue to remain a challenge despite the recent attempts to classify these borderline lesions. The term 'well differentiated tumour of uncertain malignant potential (WDT-UMP)' was introduced to classify these tumours. The present study aimed to evaluate the role of a cell cycle regulator like cyclin D1 in these tumours along with assessment of other well established PTC markers like galectin-3, HBME-1, CK19.. Thirteen cases of metastatic PTC, papillary microcarcinoma and follicular variant of PTC (FVPTC) were identified from a histological review of 510 cases. In addition, 13 cases of a subset of follicular adenomatoid nodules with focal areas showing nuclear features characteristic of PTC, identified as WDT-UMP, were also analyzed. Immunohistochemical analysis of galectin-3, HBME-1, CK19 and the proliferation markers Ki67 and cyclin D1 was performed. Lesions were analyzed for cyclin D1 gene amplification by fluorescent in-situ hybridization.. All WDT-UMP lesions showed immunolabelling of cyclin D1, Ki67; 11/ 13 cases showed immunolabelling of CK19; 10/13 cases showed immunolabelling of HBME-1 and 4/13 cases showed immunolabelling of galectin-3. Surrounding benign adenomatoid areas showed no to faint focal staining in all thirteen cases of cyclin D1, HBME-1 and galectin-3. A low rate of cyclin D1 gene amplification was identified in a significant proportion of cells in the WDT-UMP lesions as compared to surrounding benign adenomatoid areas.. Increased expression of cyclin D1 and amplification of its gene along with immunolabelling of HBME-1 in WDT-UMP lesions showing cytological features of papillary thyroid carcinoma within follicular adenomatoid nodules suggest that these areas could correspond to a precursor lesion of follicular variant of PTC. Overexpression of cyclin D1, associated with the amplification of the gene suggests that these WDT-UMP lesions are an intermediate between the benign and malignant groups making this group of lesions a reliable precursor of FVPTC.. The virtual slide(s) for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/1851820807142117.

Topics: Adenocarcinoma, Follicular; Adenoma; Adolescent; Adult; Biomarkers, Tumor; Biopsy; Blood Proteins; Carcinoma; Carcinoma, Papillary; Cell Differentiation; Cyclin D1; Female; Galectin 3; Galectins; Gene Amplification; Humans; Immunohistochemistry; In Situ Hybridization, Fluorescence; Keratin-19; Ki-67 Antigen; Male; Middle Aged; Predictive Value of Tests; Thyroid Cancer, Papillary; Thyroid Neoplasms; Up-Regulation

To identify the role of gene products associated with apoptosis and cell cycle in the pathogenesis of thyroid follicular neoplasm.. Thirty follicular adenomas (FAs), 16 follicular carcinomas (FCs), and 20 adenomatous nodules (ANs) were investigated with immunohistochemical staining of p16, p21, p27, p53, Bcl-2, Bax, Bcl-xL, and cyclin D1 via a tissue microarray method.. Bcl-2 showed a significant difference between the benign groups (AN and FA) and the malignant group (FC). Bax was significantly higher in the FC group. p53 was lowest in the AN group and highest in the FC group with significant differences between the groups. p16 was significantly higher in the FC group than in the other groups. There was a significant difference between the AN group and neoplastic lesions in terms of p21 staining. The number of cases with positive p27 was lower in the AN group than the neoplastic groups. There was no significant difference in terms of Bcl-xL and cyclin D1.. Cell cycle modulators, led by the Bcl-2 family, played an important role in the pathogenesis of thyroid follicular neoplasm, and p53, p16, and p21 in particular played a role in the carcinogenesis of FC.

Topics: Adenocarcinoma, Follicular; Adenoma; Adult; Apoptosis; bcl-2-Associated X Protein; Cell Cycle Checkpoints; Cell Cycle Proteins; Cyclin D1; Female; Humans; Hyperplasia; Immunohistochemistry; Male; Middle Aged; Thyroid Neoplasms; Thyroid Nodule; Tissue Array Analysis

Aldosterone-producing adenoma (APA) and bilateral adrenal hyperplasia are the two characteristic types of primary aldosteronism. Dysregulation of adrenal cortical cell proliferation contributes to both diseases. We previously demonstrated that APA expressed less dopamine D2 receptor than the respective non-tumor tissue and might contribute to the overproduction of aldosterone. As activation of D2 receptor inhibits the proliferation of various cells, downregulation of D2 receptor in APA may play a role in the tumorigenesis of APA. In this study, we demonstrate that D2 receptor plays a role in angiotensin II (AII)-stimulated adrenal cortical cell proliferation. The D2 receptor agonist, bromocriptine, inhibited AII-stimulated cell proliferation in primary cultures of the normal human adrenal cortex and APA through attenuating AII-induced phosphorylation of PK-stimulated cyclin D1 protein expression and cell proliferation. D2 receptor also inhibited AII-induced ERK1/2 phosphorylation. Our results demonstrate that, in addition to inhibiting aldosterone synthesis/production, D2 receptor exerts an anti-proliferative effect in adrenal cortical and APA cells by attenuating PKCμ and ERK phosphorylation. The lower level of expression of D2 receptor in APA may augment cell proliferation and plays a crucial role in the tumorigenesis of APA. Our novel finding suggests a new therapeutic target for primary aldosteronism.

Topics: Adenoma; Adrenal Cortex; Adrenal Gland Neoplasms; Aldosterone; Carcinogenesis; Cell Cycle; Cell Proliferation; Cells, Cultured; Cyclin D1; Dopamine D2 Receptor Antagonists; Flavonoids; Humans; Immunoblotting; Isoenzymes; Mitogen-Activated Protein Kinases; Phosphorylation; Protein Kinase C; Receptor, Angiotensin, Type 1; Receptors, Dopamine D2

In the pituitary the activation of cyclic adenosine 3'-5'-monophosphate (cAMP) dependent pathways generates proliferative signals in somatotrophs, whereas in pituitary cells of other lineages its effect remains uncertain. Moreover, the specific role of the two main cAMP effectors, protein kinase A (PKA) and exchange proteins directly activated by cAMP (Epac), has not been defined. Aim of this study was to investigate the effect of cAMP on pituitary adenomatous cells proliferation and to identify PKA and Epac differential involvement. We found that cAMP increased DNA synthesis and cyclin D1 expression in somatotropinomas, whereas it reduced both parameters in prolactinomas and nonfunctioning adenomas, these effects being replicated in corresponding cell lines. Moreover, the divergent cAMP effects were mimicked by Epac and PKA analogs, which activated Rap1 and CREB, respectively. In conclusion, we demonstrated that cAMP exerted opposite effects on different pituitary cell types proliferation, these effects being mediated by both Epac and PKA.

Topics: Adenoma; Animals; Cell Proliferation; Cyclic AMP; Cyclic AMP Response Element-Binding Protein; Cyclic AMP-Dependent Protein Kinases; Cyclin D1; Gene Expression Regulation, Neoplastic; Gonadotrophs; Guanine Nucleotide Exchange Factors; Humans; Lactotrophs; Pituitary Gland; Pituitary Neoplasms; Prolactinoma; Protein Subunits; rap1 GTP-Binding Proteins; Rats; Signal Transduction; Somatotrophs

The molecular bases for parathyroid carcinomas present in conjunction with sporadic primary hyperparathyroidism are not fully elucidated. Gene copy number variations (CNVs) play an important role in tumorigenesis. The aim of the current study was to explore whether the CNVs of specific tumor-associated genes are involved in parathyroid carcinogenesis.. A multiplex ligation-dependent probe amplification method was used to compare differences in copy number in 39 common tumor-associated genes among 7 patients with parathyroid carcinoma and 14 age- and sex-matched subjects with parathyroid adenoma.. It was shown that amplification of CCND1, a gene encoding cyclin D1, was more prevalent in parathyroid carcinomas than in adenomas (71 vs. 21 %, p = 0.056). This result was confirmed quantitatively by real-time polymerase chain reaction. Expression of CCND1 mRNA level was significantly higher in carcinomas than in adenomas (p = 0.003). Western blot and immunohistochemical analysis also demonstrated higher expression of CCND1 in carcinoma specimens than in adenoma samples.. It is thus inferred that gain in copy number of CCND1 is implicated in the molecular pathogenesis of parathyroid carcinoma.

Topics: Adenoma; Adult; Aged; Carcinoma; Cyclin D1; DNA Copy Number Variations; Female; Humans; Hyperparathyroidism, Primary; Male; Middle Aged; Multiplex Polymerase Chain Reaction; Parathyroid Neoplasms; Real-Time Polymerase Chain Reaction; RNA, Messenger

Insulin-like growth factor (IGF1) and its receptor display potent proliferative and antiapoptotic activities and are considered key players in malignancy. The objective of the study was to explore the role of IGF1 and its downstream pathways in the proliferation of non-functioning pituitary tumor cells and to develop a targeted therapeutic approach for the treatment of these tumors. Cultures of human non-functioning pituitary adenomas and the non-secreting immortalized rat pituitary tumor cell line MtT/E were incubated with IGF1, IGF1 receptor inhibitor or both, and cell viability, proliferation and signaling were examined. Our results show that IGF1 elevated cell proliferation and enhanced cell cycle progression as well as the expression of cyclins D1 and D3. IGF1 also induced the phosphorylation of ERK, Akt and p70S6K. On the other hand, the selective IGF1R inhibitor NVP-AEW541 abrogated IGF1-induced cell proliferation as well as IGF1 receptor phosphorylation and downstream signaling.

Topics: Adenoma; Adult; Aged; Aged, 80 and over; Animals; Antineoplastic Agents; Cell Cycle; Cell Line, Tumor; Cell Proliferation; Cyclin D1; Cyclin D3; Female; Humans; Insulin-Like Growth Factor I; Male; Middle Aged; Pituitary Neoplasms; Protein Processing, Post-Translational; Pyrimidines; Pyrroles; Rats

Parathyroid cancer is rare. Differentiating parathyroid carcinoma from degenerative changes at histopathology can be difficult and studies investigating the value of single immunohistochemical markers have had variable results. In this study we aimed to investigate whether a panel of immunohistochemistry markers could aid the diagnosis of parathyroid cancer.. All cases of parathyroid cancer at our institution from 1998 to 2012 were identified retrospectively. Cases were classified as definite cancers (those with evidence of metastatic spread) or histological cancers (those with features of carcinoma without evidence of metastasis). Controls with benign parathyroid disease were included for comparison. Immunohistochemistry for parafibromin, galectin-3, PGP9.5, Ki67, and cyclin D1 was analysed by an experienced endocrine pathologist.. There were 24 cases and 14 benign adenomas. Four cases had evidence of metastatic spread and 20 were diagnosed on histological criteria alone. Sixteen of the 24 cases had further surgery with ipsilateral thyroid lobectomy and 15 also had a prophylactic level VI lymph node dissection. Apart from one patient with distant metastases at presentation, none developed recurrence at follow-up (median = 38 months). Immunohistochemistry results associated with parathyroid cancer were seen in 11/24 parafibromin, 13/24 galectin-3, 8/24 PGP9.5, 5/24 Ki67, and 2/24 cyclin D1. None of the controls had immunohistochemical staining suggestive of cancer. Nineteen of the 24 patients had at least one immunohistochemical result associated with parathyroid cancer (sensitivity 79 %, specificity 100 %). Cyclin D1 did not suggest malignancy in any case that did not already have another abnormal marker, and so did not add value to the panel in this study.. A panel of immunohistochemistry (PGP9.5, galectin-3, parafibromin, and Ki67) is better than any single marker and can be used to supplement classical histopathology in diagnosing parathyroid cancer.

Topics: Adenoma; Adult; Aged; Aged, 80 and over; Biomarkers, Tumor; Carcinoma; Case-Control Studies; Cyclin D1; Female; Galectin 3; Humans; Immunohistochemistry; Ki-67 Antigen; Male; Middle Aged; Neoplasm Proteins; Parathyroid Neoplasms; Retrospective Studies; Sensitivity and Specificity; Tumor Suppressor Proteins; Ubiquitin Thiolesterase

The Wnt and Notch1 signaling pathways play major roles in intestinal development and tumorigenesis. Sub-cellular localization of β-catenin has been implicated in colorectal carcinogenesis. However, the β-catenin and Notch intracellular domain (NICD) interaction has to be addressed. Immunohistochemistries of β-catenin, NICD, and dual immunofluorescence of β-catenin and NICD were analyzed in colorectal tissues and HT29 cell line. Moreover, real-time PCR analysis of CyclinD1, Hes1 and MUC2 was done in HT29 cells upon N-[N-(3, 5-difluorophenacetyl)-L-alanyl]-S-phenylglycine t-butyl ester (DAPT) treatment. Dual staining emphasized the strong interaction of β-catenin and NICD in adenoma and adenocarcinoma than in normal tissues. Hes1 transcript levels were decreased 1.5- and 7.1-fold in 12.5 and 25 µM DAPT-treated HT29 cells. CyclinD1 transcript levels decreased 1.2- and 1.6-fold, and MUC2 transcript level increased 4.3- and 7.5-fold in 12.5 and 25 µM DAPT-treated HT29 cells. The results of this study showed that the sub-cellular localization of β-catenin converges with NICD inducing proliferation through the activation of CyclinD1 and Hes1. Moreover, the inhibition of Notch1 signaling by DAPT leads to the arrest of cell proliferation and induces apoptosis leading to the upregulation of MUC2, a secretory cell lineage marker.

Topics: Adenocarcinoma; Adenoma; Basic Helix-Loop-Helix Transcription Factors; beta Catenin; Cell Proliferation; Colonic Neoplasms; Colorectal Neoplasms; Cyclin D1; Dipeptides; Dose-Response Relationship, Drug; Gene Expression Regulation, Neoplastic; Homeodomain Proteins; HT29 Cells; Humans; Mucin-2; Protein Structure, Tertiary; Receptor, Notch1; Reference Values; Signal Transduction; Transcription Factor HES-1

Colorectal cancer (CRC) is the second leading cause of death from cancer in the United States. Colorectal cancers have a prolonged latency following initiation that may span decades providing ample time for implementing a chemoprevention strategy that could block or reverse the progression to CRC. Cdk4 pathway alterations have been linked to a number of cancers including CRC. In these experiments we focused on the Cdk4 pathway and its role in intestinal tumorigenesis as a possible target in chemoprevention strategies.. We evaluated the effect of Cdk4 blockade on the prevention of intestinal tumor formation by crossing Cdk4(-/-) mice to Apc(-/+) mice. In addition, we tested the effect of the dietary compound silibinin on the Cdk4 pathway in Apc(-/+) mice and HT-29 colon cancer cells in culture.. Cdk4(-/-) mice backcrossed to Apc(-/+) mice reduced intestinal adenoma formation compared to Apc(-/+) controls. Silibinin effectively targeted the Cdk4 pathway causing hypophosphorylation of the retinoblastoma protein, inhibited cell growth, and induced apoptosis. As a result silibinin blocked the development of intestinal adenomas by 52% in this genetic model (Apc(-/+) mice) of early events in colorectal cancer formation. No toxic abnormalities were detected in mice which received silibinin.. Modification of the Cdk4 pathway using a natural plant-derived compound such as silibinin may be a useful chemopreventive strategy for colorectal carcinomas.

Topics: Adenoma; Animals; Apoptosis; Cell Line, Tumor; Cell Proliferation; Cell Survival; Chemoprevention; Colorectal Neoplasms; Cyclin D1; Cyclin-Dependent Kinase 4; Disease Models, Animal; Female; Genes, APC; Humans; Ki-67 Antigen; Mice; Mice, Knockout; Retinoblastoma Protein; Signal Transduction; Silybin; Silymarin

To explore underlying molecular mechanisms in the pathogenesis of symptomatic sporadic primary hyperparathyroidism (PHPT).. Forty-one parathyroid adenomas from patients with symptomatic PHPT and ten normal parathyroid glands either from patients with PHPT (n=3) or from euthyroid patients without PHPT during thyroid surgery (n=7) were analyzed for vitamin D receptor (VDR), calcium-sensing receptor (CASR), cyclin D1 (CD1), and parathyroid hormone (PTH) expressions. The protein expressions were assessed semiquantitatively by immunohistochemistry, based on percentage of positive cells and staining intensity, and confirmed by quantitative real-time PCR.. Immunohistochemistry revealed significant reductions in VDR (both nuclear and cytoplasmic) and CASR expressions and significant increases in CD1 and PTH expressions in adenomatous compared with normal parathyroid tissue. Consistent with immunohistochemistry findings, both VDR and CASR mRNAs were reduced by 0.36- and 0.45-fold change (P<0.001) and CD1 and PTH mRNAs were increased by 9.4- and 17.4-fold change respectively (P<0.001) in adenomatous parathyroid tissue. PTH mRNA correlated with plasma PTH (r=0.864; P<0.001), but not with adenoma weight, while CD1 mRNA correlated with adenoma weight (r=0.715; P<0.001). There were no correlations between VDR and CASR mRNA levels and serum Ca, plasma intact PTH, or 25-hydroxyvitamin D levels. In addition, there was no relationship between the decreases in VDR and CASR mRNA expressions and the increases in PTH and CD1 mRNA expressions.. The expression of both VDR and CASR are reduced in symptomatic PHPT in Asian Indians. In addition, CD1 expression was greatly increased and correlated with adenoma weight, implying a potential role for CD1 in adenoma growth and differential clinical expression of PHPT.

Topics: Adenoma; Adolescent; Adult; Aged; Child; Cyclin D1; DNA, Complementary; Female; Gene Expression Regulation, Neoplastic; Humans; Hyperparathyroidism, Primary; Immunohistochemistry; India; Male; Middle Aged; Parathyroid Glands; Parathyroid Hormone; Parathyroid Neoplasms; Real-Time Polymerase Chain Reaction; Receptors, Calcitriol; Receptors, Calcium-Sensing; RNA, Messenger; Up-Regulation; White People

Colon carcinogenesis consists of a multistep process during which a series of genetic and epigenetic adaptations occur that lead to malignant transformation. Here, we have studied the role of A20 (also known as TNFAIP3), a ubiquitin-editing enzyme that restricts NFκB and cell death signaling, in intestinal homeostasis and tumorigenesis. We have found that A20 expression is consistently reduced in human colonic adenomas than in normal colonic tissues. To further investigate A20's potential roles in regulating colon carcinogenesis, we have generated mice lacking A20 specifically in intestinal epithelial cells and interbred these with mice harboring a mutation in the adenomatous polyposis coli gene (APC(min)). While A20(FL/FL) villin-Cre mice exhibit uninflamed intestines without polyps, A20(FL/FL) villin-Cre APC(min/+) mice contain far greater numbers and larger colonic polyps than control APC(min) mice. We find that A20 binds to the β-catenin destruction complex and restricts canonical wnt signaling by supporting ubiquitination and degradation of β-catenin in intestinal epithelial cells. Moreover, acute deletion of A20 from intestinal epithelial cells in vivo leads to enhanced expression of the β-catenin dependent genes cyclinD1 and c-myc, known promoters of colon cancer. Taken together, these findings demonstrate new roles for A20 in restricting β-catenin signaling and preventing colon tumorigenesis.

Topics: Adenoma; Animals; beta Catenin; Carcinogenesis; Cells, Cultured; Colonic Neoplasms; Cyclin D1; DNA-Binding Proteins; Epithelial Cells; Gene Expression; Humans; Intestinal Mucosa; Intracellular Signaling Peptides and Proteins; Mice; Mice, Transgenic; Nuclear Proteins; Proteolysis; Proto-Oncogene Proteins c-myc; Tumor Necrosis Factor alpha-Induced Protein 3; Ubiquitination; Wnt Signaling Pathway

Smad nuclear interacting protein 1 (SNIP1) gene encodes a protein that contains a conservative C-terminal forkhead-associated domain and functions as a transcriptional coactivator to regulate cell proliferation and cancer progression. This study aimed to investigate the clinical and biological significance of SNIP1 expression in pituitary adenoma. We analyzed SNIP1 expressions in mouse fibroblast L929 cells and mouse pituitary adenoma AtT-20 cells by Western blotting. SNIP1 gene knockdown by small interfering RNA (siRNA) transfection was performed to evaluate SNIP1 function in pituitary adenoma cell lines. As expected, SNIP1 was found to be upregulated in pituitary adenoma cells. The mRNA and protein levels of SNIP1 were inhibited in AtT-20 cells transfected with siRNAs, which led to decreased proliferation, increased apoptosis, and cycle arrest of pituitary adenoma cells. Concomitantly, c-Myc and cyclin D1 protein levels were reduced. These findings may provide novel targets for the treatment of pituitary adenoma.

Topics: Adenoma; Animals; Apoptosis; Cell Line, Tumor; Cell Proliferation; Cyclin D1; G1 Phase Cell Cycle Checkpoints; Gene Expression Regulation, Neoplastic; Gene Knockdown Techniques; Intracellular Signaling Peptides and Proteins; Mice; Pituitary Neoplasms; Proto-Oncogene Proteins c-myc; RNA Interference; RNA-Binding Proteins; RNA, Messenger; RNA, Small Interfering; Up-Regulation

The rate of APC mutations in the intestine increases in middle-age. At the same period of life, plant sterol and stanol enriched functional foods are introduced to diet to lower blood cholesterol. This study examined the effect of plant stanol enriched diet on intestinal adenoma formation in the Apc(Min) mouse. Apc(Min) mice were fed 0.8% plant stanol diet or control diet for nine weeks. Cholesterol, plant sterols and plant stanols were analyzed from the caecum content and the intestinal mucosa. Levels of β-catenin, cyclin D1, epidermal growth factor receptor (EGFR) and extracellular signal-regulated kinase 1/2 (ERK1/2) were measured from the intestinal mucosa by Western blotting. Gene expression was determined from the intestinal mucosa using Affymetrix and the data were analyzed for enriched categories and pathways. Plant stanols induced adenoma formation in the small intestine, however, the adenoma size was not affected. We saw increased levels of nuclear β-catenin, phosphorylated β-catenin (Ser675 and Ser552), nuclear cyclin D1, total and phosphorylated EGFR and phosphorylated ERK1/2 in the intestinal mucosa after plant stanol feeding. The Affymetrix data demonstrate that several enzymes of cholesterol synthesis pathway were up-regulated, although the cholesterol level in the intestinal mucosa was not altered. We show that plant stanols induce adenoma formation by activating Wnt and EGFR signaling. EGFR signaling seems to have promoted β-catenin phosphorylation and its translocation into the nucleus, where the expression of cyclin D1 was increased. Up-regulated cholesterol synthesis may partly explain the increased EGFR signaling in the plant stanol-fed mice.

Topics: Adenoma; Animals; beta Catenin; Cecum; Cholesterol; Cyclin D1; ErbB Receptors; Female; Gene Expression Regulation; Genes, APC; Intestinal Mucosa; Intestinal Neoplasms; Male; Mice; Mice, Inbred C57BL; Mice, Mutant Strains; Mitogen-Activated Protein Kinase 3; Phytosterols; Proto-Oncogene Proteins c-akt; Serine; Sitosterols; Sterol Regulatory Element Binding Protein 2; Up-Regulation; Wnt Signaling Pathway

To evaluate the effects of oligonol administration on experimentally induced colitis and colonic adenoma formation.. Oral administration of oligonol protected against mouse colitis induced by dextran sulfate sodium (DSS). Under the same experimental conditions, oligonol administration significantly inhibited the activation of nuclear factor-kappa B and signal transducer and activator of transcription (STAT) 3 and expression of cyclooxygenase-2 (COX-2), inducible nitric oxide synthase (iNOS), and cyclin D1 in the mouse colon. Further, oligonol inhibited azoxymethane-initiated and DSS-promoted adenoma formation in the mouse colon. Oligonol administration also attenuated lipid peroxidation (malondialdehyde) and protein oxidation (4-hydroxy-2-nonenal), thereby preventing oxidative stress-induced apoptosis of colonic epithelial cells. In vitro studies demonstrated that oligonol treatment reduced lipopolysaccharide-induced expression of interleukin (IL)-1β, tumor necrosis factor α, il-6, cox-2, and inos in murine macrophage RAW 264.7 cells. In another study, oligonol upregulated the antioxidant gene expression in the intestinal epithelial CCD841CoN cells and in the mouse colon.. Oligonol, an innovative formulation of catechin-type oligomers derived from the lychee fruit extract, was tested in this study for the first time to evaluate its effects on experimentally induced colitis and colonic adenoma formation in mice.. Oligonol is effective in protecting against DSS-induced mouse colitis and colon carcinogenesis, suggesting that this polyphenol formulation may have a potential for the amelioration of inflammatory bowel disease and related disorders.

Topics: Adenoma; Animals; Antioxidants; Apoptosis; Carcinogenesis; Catechin; Cell Line; Colitis; Colonic Neoplasms; Cyclin D1; Cyclooxygenase 2; Dextran Sulfate; Humans; Inflammation; Interleukin-1beta; Lipid Peroxidation; Male; Mice; Mice, Inbred ICR; NF-kappa B; Nitric Oxide Synthase Type II; Oxidative Stress; Phenols; STAT3 Transcription Factor; Tumor Necrosis Factor-alpha

Surveillance colonoscopy is an important strategy for prevention of colorectal cancer. 5-aminosalicylate (ASA) (mesalazine) is discussed as a chemopreventive agent as it reduces the cancer risk in ulcerative colitis patients. The current study analyses the effect of 5-ASA on Wnt/β-catenin signaling in vitro and in vivo in colon epithelial cells. The effect of 5-ASA was determined using a β-catenin/T-cell factor (TCF)-reporter assay and by western blotting in cultured colon cancer cells. Formalin fixed paraffin embedded material from 227 polyps removed from a subgroup of 56 patients, who participated in a randomized placebo-controlled 3-year prevention trial with 5-ASA was evaluated according to histomorphological characteristics and expression of β-catenin and target genes Cox2, cyclin D1 and E-cadherin as well as ornithine decarboxylase (ODC). Patients were grouped into a low-risk and a high-risk group according to the number of adenomas at initial colonoscopy. ß-catenin/TCF signaling activity was significantly reduced by 5-ASA treatment possibly through a reduction in ß-catenin levels. Moreover, 5-ASA significantly reduced ß-catenin levels and nuclear localization in patients' adenomas. In addition, 5-ASA also significantly changed expression of the downstream targets Cox2, cyclin D1 and E-cadherin, correlating with ß-catenin status. Moreover, 5-ASA significantly reduced levels of ODC in vivo. Expression of p53 was unaltered by the 5-ASA treatment. Our study shows a significant in vitro and long-term in vivo effect of 5-ASA on ß-catenin signaling as a key signaling pathway in the development of colorectal adenoma. Therefore, we suggest the use of 5-ASA as a promising drug for prevention of sporadic colorectal carcinoma.

Topics: Adenoma; beta Catenin; Cadherins; Cell Line, Tumor; Colitis, Ulcerative; Colorectal Neoplasms; Cyclin D1; Cyclooxygenase 2; Disease Progression; Epithelial Cells; Female; Gene Expression Regulation, Neoplastic; Genes, Reporter; Humans; Male; Mesalamine; Ornithine Decarboxylase; Signal Transduction; TCF Transcription Factors; Tumor Suppressor Protein p53; Wnt Proteins; Wnt Signaling Pathway

Mutation of tumor suppressor gene, adenomatous polyposis coli (APC), is the primary molecular event in the development of most intestinal carcinomas. Animal model with APC gene mutation is an effective tool for study of preventive approaches against intestinal carcinomas. We aimed to evaluate the effect of Riccardin D, a macrocyclic bisbibenzyl compound, as a chemopreventive agent against intestinal adenoma formation in APC(Min/+) mice.. APC(Min/+) mice were given Riccardin D by p.o. gavage for 7 weeks. Mice were sacrificed, and the number, size and histopathology of intestinal polyps were examined under a microscope. We performed immunohistochemical staining, western blotting, reverse transcriptase-polymerase chain reaction (RT-PCR) and enzyme-linked immunosorbent assay (ELISA) in intestinal polyps to investigate the mechanism of chemopreventive effect of Riccardin D.. Riccardin D treatment resulted in a significant inhibition of intestinal adenoma formation, showing a reduction of polyp number by 41.7%, 31.1% and 44.4%, respectively, in proximal, middle and distal portions of small intestine. The activity of Riccardin D against polyp formation was more profound in colon, wherein Riccardin D decreased polyp number by 79.3%. Size distribution analysis revealed a significant reduction in large-size polyps (2-3 mm) by 40.0%, 42.5% and 33.3%, respectively, in proximal, middle and distal portions of small intestine, and 77.8% in colon. Histopathological analysis of the intestinal polyps revealed mostly hyperplastic morphology without obvious dysplasia in Riccardin D-treated mice. Molecular analyses of the polyps suggested that the inhibitory effect of Riccardin D on intestinal adenoma formation was associated with its abilities of reduction in cell proliferation, induction of apoptosis, antiangiogenesis, inhibition of the Wnt signaling pathway and suppression of inflammatory mediators in polyps.. Our results suggested that Riccardin D exerts its chemopreventive effect against intestinal adenoma formation through multiple mechanisms including anti-proliferative, apoptotic, anti-angiogenic and anti-inflammatory activity.

Topics: Adenoma; Adenomatous Polyposis Coli Protein; Animals; Apoptosis; beta Catenin; Biological Products; Caspases; Cell Proliferation; Colon; Cyclin D1; Cyclooxygenase 2; Hepatophyta; Inflammation; Intestinal Neoplasms; Intestinal Polyps; Intestine, Small; Mice; Neovascularization, Pathologic; NF-kappa B; Phenyl Ethers; Precancerous Conditions; Signal Transduction; Stilbenes

Adenocarcinoma of the colon and rectum is the third most common cause of cancer deaths and the sixth most common cancer in the world. Adenomas are benign neoplastic lesions which can be transformed into carcinomas, but this is usually not the case. There should be some risk factors which lead to the development of carcinomas into adenomas. The aim of this study is to find out the early changes and high risk factors related to carcinogenesis in colonic polyps.. In this study, we reviewed nearly 1000 colonoscopic biopsies and chose 72 biopsies. We developed three groups (tubular adenomas group 1, villous adenomas group 2, normal mucosa group 3); each group had 24 different biopsies. P53, Ki-67, bcl-2, cyclin D1, E-cadherin, c-erb B2 immunohistochemistry and human papillomavirus (HPV) in-situ hybridization were used for analysis.. Five of the seventy-two cases were positive in HPV in-situ analysis. Four of them were villous adenomas and one was a tubular adenoma. Ki-67 expression was limited only to crypts in group 3 but in groups 1 and 2, Ki-67 expression was seen both in crypt epithelium and surface epithelium. Cyclin D1, c-erb B2, bcl-2 expression was significantly increased in neoplastic polyps.. Ki-67 expression, both in the crypt and surface epithelium, and cyclin D1, c-erb B2, bcl-2 over-expression may be a clue of dysplastic epithelium and if the role of HPV is elucidated and shown to be important in colonic carcinogenesis, then vaccination might prevent carcinogenesis caused by HPV.

Topics: Adenoma; Aged; Aged, 80 and over; Cadherins; Cell Transformation, Neoplastic; Colonic Neoplasms; Colonic Polyps; Cyclin D1; Female; Humans; Ki-67 Antigen; Male; Middle Aged; Proto-Oncogene Proteins c-bcl-2; Receptor, ErbB-2; Rectal Neoplasms; Tumor Suppressor Protein p53

Genetic abnormalities, such as those of multiple endocrine neoplasia type 1 (MEN1) and Cyclin D1 (CCND1) genes, occur in <50% of nonhereditary (sporadic) parathyroid adenomas.. To identify genetic abnormalities in nonhereditary parathyroid adenomas by whole-exome sequence analysis.. Whole-exome sequence analysis was performed on parathyroid adenomas and leukocyte DNA samples from 16 postmenopausal women without a family history of parathyroid tumors or MEN1 and in whom primary hyperparathyroidism due to single-gland disease was cured by surgery. Somatic variants confirmed in this discovery set were assessed in 24 other parathyroid adenomas.. Over 90% of targeted exons were captured and represented by more than 10 base reads. Analysis identified 212 somatic variants (median eight per tumor; range, 2-110), with the majority being heterozygous nonsynonymous single-nucleotide variants that predicted missense amino acid substitutions. Somatic MEN1 mutations occurred in six of 16 (∼35%) parathyroid adenomas, in association with loss of heterozygosity on chromosome 11. However, no other gene was mutated in more than one tumor. Mutations in several genes that may represent low-frequency driver mutations were identified, including a protection of telomeres 1 (POT1) mutation that resulted in exon skipping and disruption to the single-stranded DNA-binding domain, which may contribute to increased genomic instability and the observed high mutation rate in one tumor.. Parathyroid adenomas typically harbor few somatic variants, consistent with their low proliferation rates. MEN1 mutation represents the major driver in sporadic parathyroid tumorigenesis although multiple low-frequency driver mutations likely account for tumors not harboring somatic MEN1 mutations.

Topics: Adenoma; Aged; Aged, 80 and over; Cyclin D1; DNA Mutational Analysis; Exome; Female; Genetic Variation; Humans; Hyperparathyroidism, Primary; Male; Middle Aged; Multiple Endocrine Neoplasia Type 1; Parathyroid Neoplasms; Shelterin Complex; Telomere-Binding Proteins

We examined the influence that rare variants and low-frequency polymorphisms in the cancer candidate gene CCND1 have on the development of multiple intestinal adenomas and the early onset of colorectal cancer. Individuals with <100 multiple polyps and patients with colorectal cancer diagnosed before 50 years of age were recruited in UK, and screened for sequence changes in the coding and regulatory regions of CCND1. A set of about 800 UK control individuals was genotyped for the variants discovered in the cases. Variants in the promoter, intron-exon boundaries and untranslated regions of the CCND1 gene had higher frequencies in cases than in controls. Five of these variants were typed in a set of French multiple adenoma and early-onset patients, who also showed higher allele frequencies than UK controls. When pooled together, variants with frequencies lower than 1% conferred an increased risk of disease that was significant in the multiple adenoma group (odds ratio (OR) 2.2; 95% confidence interval, 1.1-4.4; P = 0.03). Most variants had a putative functional effect when assessed in silico. We conclude that rare variants of CCND1 are risk factors for colorectal cancer, with considerably larger effects than common polymorphisms, and as such should be systematically evaluated in susceptibility studies.

Topics: Adenoma; Adult; Age of Onset; Case-Control Studies; Colorectal Neoplasms; Cyclin D1; Female; France; Gene Frequency; Humans; Male; Middle Aged; Neoplasms, Multiple Primary; Polymorphism, Single Nucleotide; United Kingdom

Nonselective cyclooxygenase (COX) inhibitors target many of the same cancer-associated molecular pathways as COX-2-specific inhibitors. Although these nonsteroidal anti-inflammatory drugs (NSAIDs) are often associated with gastrointestinal toxicity, there is renewed interest in their use as colorectal cancer (CRC) chemopreventive agents due to the adverse side effects associated with long-term use of selective COX-2 inhibitors. In this study, we investigated the effects of long-term use (up to 25 years) of NSAIDs (ibuprofen or aspirin) on adenoma pathology and β-catenin-mediated signaling in sporadic human colon adenomas. Although NSAID use did not impact overall adenoma size or degree of dysplasia, it did cause a significant inhibition of nuclear β-catenin localization, which correlated with suppression of cyclin D1 expression. To further elucidate the effect of these agents in regulating β-catenin, we treated SW480 colon cancer cells with a panel of NSAIDs and determined their effects on β-catenin levels and cellular localization. In agreement with our in vivo results, both S-ibuprofen and aspirin were found to decrease total levels of β-catenin while increasing its phosphorylation. In addition, S-ibuprofen induced both degradation of IκBα and nuclear localization of NF-κB. Despite its nuclear localization, however, the activation of the NF-κB target genes, Bcl-2, survivin, and cyclin D1, was suppressed. This reduction in NF-κB transcriptional activity may be due to increased phosphorylation of GSK-3β following S-ibuprofen treatment. These data suggest that ibuprofen can effectively target both the Wnt/β-catenin and NF-κB pathways, and potentially uncovers a novel mechanism through which NSAIDS may exert their chemopreventive efficacy.

Topics: Adenoma; Adult; Aged; Anti-Inflammatory Agents, Non-Steroidal; Aspirin; beta Catenin; Blotting, Western; Cell Nucleus; Colonic Neoplasms; Cyclin D1; Female; Fluorescent Antibody Technique; Glycogen Synthase Kinase 3; Glycogen Synthase Kinase 3 beta; Humans; Ibuprofen; Immunoenzyme Techniques; Male; Middle Aged; NF-kappa B; Phosphorylation; Signal Transduction; Tumor Cells, Cultured; Wnt Proteins

Cyclooxygenase (COX)-2 is a key molecular target of colon cancer prevention. However, the mechanisms by which COX-2 inhibitors confer protective effects against tumour development are not completely understood. The aim of this study was to elucidate the effects of NS-398 in the 1,2-dimethylhydrazine (DMH) mouse model with respect to alteration in the expression of COX-2 and E-cadherin-catenin complex. Alterations in cell proliferation, apoptosis, and vascular density were investigated. NS-398 showed reduced COX-2 immunoreactivity in adenomas with a decrease in vascular density in non-dysplastic mucosa. Adenomas revealed increased E-cadherin and beta-catenin reactivity. NS-398 reduced the percentages of tumour cells with nuclear localisation of beta-catenin and cyclin D1. Bromodeoxyuridine (BrdUrd) index in adenomas was significantly higher in untreated animals. NS-398 resulted in significant increase in apoptosis in adenomas. Our results suggest a protective role of NS-398 on tumour development associated with reduced COX-2 expression, reduced vascular density and perturbation of beta-catenin signalling pathway.

Topics: 1,2-Dimethylhydrazine; Adenoma; Animals; Apoptosis; beta Catenin; Bromodeoxyuridine; Carcinogens; Cell Nucleus; Cell Proliferation; Colonic Neoplasms; Cyclin D1; Cyclooxygenase 2; Cyclooxygenase Inhibitors; Factor VIII; Female; Mice; Mice, Inbred BALB C; Neoplasms, Experimental; Neovascularization, Pathologic; Nitrobenzenes; Prostaglandins; Signal Transduction; Sulfonamides; TCF Transcription Factors; Tumor Burden

High doses of niacin (nicotinic acid) used to treat dyslipidemias cause flushing, due to high levels of prostaglandin D(2) (PGD(2)). GPR109A, a G-protein coupled receptor, triggers the flushing in the skin. In addition to boosting PGD(2), niacin binding to GPR109A activates the entire prostanoid cascade. We found that GPR109A occurs throughout the gastrointestinal tract. Mice that alternated between a 1% niacin diet and a control diet had higher urinary prostaglandin E(2) (PGE(2)) metabolite levels when on niacin (2.8-fold increase; 95% confidence interval, 1.8-3.9). PGE(2) promotes tumors in the intestines, whereas PGD(2) may have an opposite effect, on the basis of our report showing that transgenic hematopoietic prostaglandin D synthase suppresses intestinal adenomas in Apc(Min/+) mice. To determine if either tumor growth or tumor suppression prevails, we fed Apc(Min/+) mice a 1% niacin diet and assessed tumor development. A 1% niacin diet did not affect the number of tumors scored histologically in Apc(Min/+) mice at 14 wk (33 mice on niacin, 33 controls). Although niacin stimulates production of various prostaglandins, our results support an interpretation that very high intakes of niacin are safe in relation to intestinal tumors in this model.

Topics: Adenoma; Animals; Cyclin D1; Diet; Dose-Response Relationship, Drug; Female; Flushing; Humans; Intestines; Intramolecular Oxidoreductases; Isomerases; Male; Mice; Mice, Inbred C57BL; Mice, Knockout; Neoplasms; Neoplasms, Experimental; Niacin; Phospholipases A2, Cytosolic; Prostaglandins; Receptors, G-Protein-Coupled; Receptors, Nicotinic; RNA, Messenger; Vascular Endothelial Growth Factor A

Pituitary tumors are a common form of endocrine neoplasia. However few studies assessed the expression of the principal cyclin regulating checkpoint exit, cyclin D1. Cyclin D1 expression in pituitary tumors and its possible relation to MIB-1 and p27/Kip1 labeling indices (LIs) was explored.. We studied a total of 199 pituitaries, including normal pituitaries (n=7), pituitary adenomas (n=187), and pituitary carcinoma (n=5). All tissues were tested as cores of archived tissue microarrays that were immunostained for cyclin D1, MIB-1 and p27 using a standard technique. Tissue cores were subjected to automated analysis to evaluate the staining LIs.. No cyclin D1 positive cells in the normal anterior pituitary gland was found. Sparse nuclear staining was noted in pituitary tumors. Higher expression of cyclin D1 was noted in pituitary carcinomas compared to adenomas (p<0.001), in non-functioning adenomas compared to functioning ones (p<0.001) in macroadenomas versus microadenomas (p=0.017) and in recurrent non recurrent adenomas (p<0.001). Cyclin D1 LI and MIB-1 LI were related among adenomas (p<0.001) and carcinomas (p=0.041). p27 LI was neither related to pituitary adenoma recurrence nor invasion.. Expression of cyclin D1 in pituitary tumors is related to cell proliferation, recurrence, and metastatic potential. Nuclear cyclin D1 expression is a good marker of aggressive behavior in pituitary tumors.

Topics: Adenoma; Adult; Carcinoma; Cyclin D1; Cyclin-Dependent Kinase Inhibitor p27; Female; Gene Expression; Humans; Male; Middle Aged; Neoplasm Invasiveness; Neoplasm Recurrence, Local; Pituitary Neoplasms; ROC Curve; Tissue Array Analysis; Ubiquitin-Protein Ligases

The identification of follicular thyroid adenoma-associated transcripts will lead to a better understanding of the events involved in pathogenesis and progression of follicular tumours. Using Serial Analysis of Gene Expression, we identified five genes that are absent in a malignant follicular thyroid carcinoma (FTC) library, but expressed in follicular adenoma (FTA) and normal thyroid libraries.. NR4A1, one of the five genes, was validated in a set of 27 normal thyroid tissues, 10 FTAs and 14 FTCs and three thyroid carcinoma cell lines by real time PCR. NR4A1 can be transiently increased by a variety of stimuli, including lithium, which is used as adjuvant therapy of thyroid carcinoma with (131)I. We tested if lithium could restore NR4A1 expression. The expression of other genes potentially involved in the same signalling pathway was tested. To this end, lithium was used at different concentration (10 mm or 20 mm) and time (2 h and 24 h) and the level of expression was tested by quantitative PCR. We next tested if Lithium could affect cell growth and apoptosis.. We observed that NR4A1 expression was under-expressed in most of the FTCs investigated, compared with expression in normal thyroid tissues and FTAs. We also found a positive correlation between NR4A1 and FOSB gene expression. Lithium induced NR4A1 and FOSB expression, reduced CCDN1 expression, inhibited cell growth and triggered apoptosis in a FTC cell line.. NR4A1 is under-expressed in most of FTCs. The loss of expression of both NR4A1 and the Wnt pathway gene FOSB was correlated with malignancy. This is consistent with the hypothesis that its loss of expression is part of the transformation process of FTCs, either as a direct or indirect consequence of Wnt pathway alterations. Lithium restores NR4A1 expression, induces apoptosis and reduces cell growth. These findings may explain a possible molecular mechanism of lithium's therapeutic action.

Topics: Adenocarcinoma, Follicular; Adenoma; Apoptosis; Cell Line, Tumor; Cell Proliferation; Chemotherapy, Adjuvant; Cyclin D1; DNA-Binding Proteins; Dose-Response Relationship, Drug; Down-Regulation; Humans; Lithium Compounds; Nuclear Receptor Subfamily 4, Group A, Member 1; Proto-Oncogene Proteins c-fos; Receptors, Steroid; Signal Transduction; Thyroid Neoplasms; Wnt Proteins

Laterally spreading tumors (LSTs) are considered a special subtype of superficial colorectal tumor. This study was performed to characterize the clinicopathological features and examine activation of the Wnt/beta-catenin pathway in LSTs and protruded-type colorectal adenomas (PAs). Fifty LSTs and 54 PAs were collected, and their clinicopathological characteristics were compared. The expression of E-cadherin, beta-catenin, glycogen synthase kinase-3beta (GSK-3beta), phosphorylated GSK-3beta, (phospho-GSK-3beta), cyclin D1, and c-myc was investigated by immunohistochemical staining on serial sections. Patients with LSTs were significantly older than those bearing PAs (63.4 vs 47.4 years old; p<0.001). The mean size of LSTs was significantly larger than that of PAs (27.0 mm vs 14.6 mm; p<0.01). Forty-eight percent of LSTs were located in the proximal colon, which was significantly higher than that of PAs (18.5%; p<0.05). Expression of beta-catenin, phospho-GSK-3beta, cyclin D1, and c-myc was significantly increased in LSTs compared with PAs (p<0.05). However, E-cadherin and total GSK-3beta expression was not significantly different between the two groups. The level of beta-catenin expression correlated strongly with phospho-GSK-3beta, cyclin D1, and c-myc expression in LSTs but not in PAs. Our findings suggest that activation of the Wnt/beta-catenin pathway is more prevalent in LSTs than in PAs, suggesting that phosphorylation-dependent inactivation of GSK-3beta may be involved in LST carcinogenesis.

Topics: Adenoma; beta Catenin; Biomarkers, Tumor; Colorectal Neoplasms; Cyclin D1; Glycogen Synthase Kinase 3; Glycogen Synthase Kinase 3 beta; Humans; Immunohistochemistry; Phosphorylation; Proto-Oncogene Proteins c-myc

Von Hippel-Lindau (VHL) disease is an inherited syndrome caused by germline mutation in the VHL tumor suppressor gene predisposing to pancreatic endocrine tumors (PET). Whether these tumors derive from preexisting endocrine microadenomatosis as in multiple endocrine neoplasia type 1 (MEN1) is yet unknown. pVHL regulates hypoxia-inducible factor (HIF) that causes transcription activity of target genes like carbonic anhydrase 9 (CA9), vascular endothelial growth factor (VEGF), and cyclin D1. Our aim was to look for overexpression of these molecules to identify precursor endocrine lesions in the pancreas of VHL patients.. Nontumoral pancreas of 18 VHL patients operated on for PET, was examined for microadenomatosis (70% of VHL patients operated on for PET. These results demonstrate that the pVHL/HIF pathway is involved very early in pancreatic endocrine tumorigenesis in this disease.

Topics: Adenoma; Adult; Antigens, CD34; Antigens, Neoplasm; Basic Helix-Loop-Helix Transcription Factors; Biomarkers, Tumor; Carbonic Anhydrase IX; Carbonic Anhydrases; Chromogranin A; Cyclin D1; Female; Glucagon; Humans; Hypoxia-Inducible Factor 1, alpha Subunit; Immunohistochemistry; Insulin; Male; Middle Aged; Multiple Endocrine Neoplasia Type 1; Mutation; Pancreas; Pancreatectomy; Pancreatic Neoplasms; Precancerous Conditions; Vascular Endothelial Growth Factor A; von Hippel-Lindau Disease; Von Hippel-Lindau Tumor Suppressor Protein

Apc mutations cause intestinal tumorigenesis through Tcf4 activation. However, direct techniques for studying Tcf4 activation in vivo are limited. Here, we describe the development of a Tcf4-GFP reporter mouse model for directly studying Tcf4 activation. We first developed a GFP reporter construct (Tcf4-GFP) and transfected it into SW480 cells that have constitutively activated Tcf4. Reporter activity increased 47-fold. Next, we created transgenic (Tg) mice by transducing the construct into C57BL/6J mice. Fluorescence microscopy did not detect GFP in intestinal sections, but flow cytometry showed 5% of crypt cells to be GFP(+). We then established cross-bred mice (Tg x Apc(Min/+)), which have a germline Apc mutation and sustained Tcf4 activation. Here, fluorescence microscopy showed GFP(+) cells at or near the base of normal-appearing crypts. In adenomas, in which Apc is inactivated, GFP(+) signal was even greater. Immunostaining for the Tcf4 target genes survivin (BIRC5) and cyclin D1 (CCND1) showed that their expression also paralleled GFP positivity. We conclude that GFP directly reports Tcf4 activation in vivo and tracks the predicted increases in Tcf4 activation that result from Apc inactivation, and that Apc mutation contributes to survivin and cyclin D1 overexpression through Tcf4 activation. Our Tcf4 mouse should be useful in studying the effects of chemopreventive agents on Wnt signaling and changes in proliferative crypt cell populations-including stem cells-during intestinal tumorigenesis.

Topics: Adenoma; Adenomatous Polyposis Coli Protein; Animals; Basic Helix-Loop-Helix Leucine Zipper Transcription Factors; Cell Line, Tumor; Cyclin D1; Enterocytes; Female; Flow Cytometry; Green Fluorescent Proteins; Humans; Immunohistochemistry; Inhibitor of Apoptosis Proteins; Intestinal Neoplasms; Ki-67 Antigen; Luciferases; Male; Mice; Mice, Inbred C57BL; Mice, Transgenic; Microscopy, Fluorescence; Microtubule-Associated Proteins; Mutation; Nerve Tissue Proteins; Recombinant Fusion Proteins; Repressor Proteins; Survivin; TCF Transcription Factors; Transcription Factor 4

We investigated the possible mechanisms of inhibition of colorectal carcinogenesis by green tea (GT) in azoxymethane-treated (AOM) Apc(Min/+) mice. Mice received water or a 0.6% (w/v) solution of GT as the only source of beverage. GT treatment commenced at the 8th week of age and lasted for 8 wk. The treatment caused a statistically significant reduction in the number of newly formed tumors (28%, P < 0.05). Immunohistochemical analysis showed that GT decreased the levels of beta-catenin and its downstream target cyclin D1. To probe a mechanism, we further investigated the expression of retinoic X receptor alpha (RXR alpha) in AOM/Apc(Min/+) tumors. Our results show that RXR alpha is selectively downregulated in AOM/Apc(Min/+) mouse intestinal tumors. In contrast, other retinoic receptors including retinoic acid receptor alpha (RAR alpha), RAR beta, RXR beta, and RXR gamma were all expressed in Apc(Min/+) adenomas. Furthermore, our results show that RXR alpha downregulation is an early event in colorectal carcinogenesis and is independent of beta-catenin expression. GT significantly increased the protein levels of RXR alpha. In addition, RT-PCR analysis showed that GT induced a similar increase in the levels of RXR alpha mRNA. Genomic bisulfite treatment of colonic DNA followed by pyrosequencing of 24 CpG sites in the promoter region of RXR alpha gene showed a significant decrease in CpG methylation with GT treatment. The results suggest that a low concentration of GT is sufficient to desilence RXR alpha and inhibit intestinal tumorigenesis in the Apc(Min/+) mouse.

Topics: Adenoma; Animals; Azoxymethane; beta Catenin; Camellia sinensis; Carcinogens; Cyclin D1; Disease Models, Animal; DNA Methylation; Down-Regulation; Epigenesis, Genetic; Female; Genes, APC; Immunoenzyme Techniques; Intestinal Neoplasms; Male; Mice; Mice, Inbred C57BL; Mice, Knockout; Promoter Regions, Genetic; Retinoid X Receptor alpha; Reverse Transcriptase Polymerase Chain Reaction; RNA, Messenger; Tea

Low levels of serum adiponectin have been reported to be associated with obesity, diabetes, and non-alcoholic steatohepatitis (NASH), as well as several malignancies. Adiponectin knockout (KO) mice have been reported to cause insulin resistance and neointimal formation of the artery. We used adiponectin KO mice fed a high fat (HF) diet, and investigated the effect of adiponectin on the progression of steatohepatitis and carcinogenesis in vivo.. Adiponectin KO mice and wild type (WT) mice were fed a HF diet or normal chow for the periods of 24 and 48 weeks. The HF diet contained 60% of calories from fat.. The adiponectin KO mice on the HF diet showed obesity, marked elevation of serum transaminase levels, and hyperlipidemia. At 24 weeks, hepatic expression of tumor necrosis factor-alpha and procollagen alpha (I) was higher in KO mice as compared with WT mice. At 48 weeks, liver triglyceride contents in KO mice on normal chow were significantly higher than those in WT mice. Hepatocyte ballooning, spotty necrosis, and pericellular fibrosis around central veins were observed in KO mice on the HF diet. The pericellular fibrosis was more severe in KO mice on the HF diet than that in WT mice (1.62% vs 1.16%, P = 0.033). Liver adenoma and hyperplastic nodules developed in a KO mouse on the HF diet at 48 weeks (12.5%, n = 1/8), whereas no tumor was detected in WT mice (n = 10).. Adiponectin may play a protective role in the progression of NASH in the early stages by suppressing tumor necrosis factor-alpha expression and liver fibrosis.

Topics: Adenoma; Adiponectin; Alanine Transaminase; Animals; Aspartate Aminotransferases; Collagen Type I; Collagen Type I, alpha 1 Chain; Cyclin D1; Dietary Fats; Disease Models, Animal; Disease Progression; Fatty Liver; Hyperlipidemias; Hyperplasia; Liver; Liver Cirrhosis, Experimental; Liver Neoplasms; Male; Mice; Mice, Inbred C57BL; Mice, Knockout; Obesity; RNA, Messenger; Time Factors; Triglycerides; Tumor Necrosis Factor-alpha

Carcinomas of the ampulla of Vater are rare and assumed to generally arise from preexisting adenomas (adenoma-carcinoma sequence). Histologically, distinct subtypes can be distinguished that were shown to differ significantly in terms of clinical outcome. Since pathologists usually receive bioptic tissue samples of ampullary tumors obtained during endoscopy, accurate classification of carcinoma subtypes can sometimes be difficult on morphological criteria alone. We therefore performed immunohistochemistry using a panel of established marker proteins (CK7, CK20, p21, p27, ESA, bax, and ephrin-B2) on 175 carcinoma, 111 adenoma, and 152 normal mucosa specimens of the ampulla of Vater and identified distinct immunoprofiles for every carcinoma subtype. Fluorescence in situ hybridization analyses of therapeutic target genes (c-myc, EGFR1, CCND1, HER2) found CCND1 to represent the most frequently amplified gene in our series (7.5%).

Topics: Adenoma; Adolescent; Adult; Aged; Aged, 80 and over; Ampulla of Vater; bcl-2-Associated X Protein; Biomarkers, Tumor; Common Bile Duct Neoplasms; Cyclin D1; Ephrin-B2; Female; Gene Amplification; Gene Expression Regulation, Neoplastic; Humans; Immunophenotyping; Keratin-20; Keratin-7; Male; Middle Aged; Proliferating Cell Nuclear Antigen; Proto-Oncogene Proteins c-myc; Receptor, ErbB-2; Young Adult

Colonic carcinogenesis involves the progressive dysregulation of homeostatic mechanisms that control growth. The epidermal growth factor (EGF) receptor (EGFR) regulates colonocyte growth and differentiation and is overexpressed in many human colon cancers. A requirement for EGFR in colonic premalignancy, however, has not been shown. In the current study, we used a specific EGFR antagonist, gefitinib, to investigate this role of the receptor in azoxymethane colonic premalignancy. The azoxymethane model shares many clinical, histologic, and molecular features of human colon cancer. Mice received azoxymethane i.p. (5 mg/kg/wk) or saline for 6 weeks. Animals were also gavaged with gefitinib (10 mg/kg body weight) or vehicle (DMSO) thrice weekly for 18 weeks, a dose schedule that inhibited normal receptor activation by exogenous EGF. Compared with control colonocytes [bromodeoxyuridine (BrdUrd), 2.2+/-1.2%], azoxymethane significantly increased proliferation (BrdUrd, 12.6+/-2.8%), whereas gefitinib inhibited this hyperproliferation (BrdUrd, 6.2+/-4.0%; <0.005). Azoxymethane significantly induced pro-transforming growth factor-alpha (6.4+/-1.3-fold) and increased phospho-(active) EGFR (5.9+/-1.1-fold), phospho-(active) ErbB2 (2.3+/-0.2-fold), and phospho-(active) extracellular signal-regulated kinase (3.3+/-0.4-fold) in premalignant colonocytes. Gefitinib inhibited activations of these kinases by >75% (P<0.05). Gefitinib also significantly reduced the number of large aberrant crypt foci and decreased the incidence of colonic microadenomas from 75% to 33% (P<0.05). Gefitinib concomitantly decreased cell cycle-regulating cyclin D1 and prostanoid biosynthetic enzyme cyclooxygenase-2 in microadenomas, suggesting that these regulators are key targets of EGFR in colonic carcinogenesis. These results show for the first time that EGFR signaling is required for early stages of colonic carcinogenesis. Our findings suggest, moreover, that inhibitors of EGFR might be useful in chemopreventive strategies in individuals at increased risk for colonic malignancies.

Topics: Adenoma; Animals; Azoxymethane; beta Catenin; Carcinogens; Cell Transformation, Neoplastic; Colonic Neoplasms; Cyclin D1; Cyclooxygenase 2; Cyclooxygenase 2 Inhibitors; Disease Models, Animal; ErbB Receptors; Gefitinib; Genes, ras; Male; Mice; Mice, Inbred A; Mutation; Quinazolines; Signal Transduction; Up-Regulation

HRPT2 gene mutations are associated with parathyroid carcinomas, and absence of parafibromin immunoreactivity has been suggested as a diagnostic marker of malignancy. The aim of our study was to extend parafibromin studies in a series of benign and malignant parathyroid tumors and cross-validate the results of immunohistochemistry with those of HRPT2 analysis.. We performed parafibromin and cyclin D1 immunostaining and HRPT2 gene analysis using loss of heterozygosity studies and sequencing analysis in parathyroid specimens from 11 patients with carcinoma (eleven primary tumors, one skin, and four lung metastases), 22 with sporadic adenomas, and 4 with atypical adenomas.. Ten out of eleven parathyroid cancers were negative for parafibromin staining and showed HRPT2 gene abnormalities. The remaining sample was negative for immunostaining and genetic analyses. All but one sporadic adenomas showed parafibromin immunoreactivity and no HRPT2 gene abnormalities. The sample with negative immunostaining carried an HRPT2 mutation. Two atypical adenomas were positive and two negative with parafibromin staining. No HRPT2 abnormalities were found in these samples. Cyclin D1 expression was heterogeneous and there was no relationship between expression/expression level of cyclin D1 and parafibromin expression.. We have shown that negative parafibromin staining is almost invariably associated with HRPT2 mutations and confirm that loss of parafibromin staining strongly predicts parathyroid malignancy. In clinical practice, these tests could be particularly useful in the subset of parathyroid tumors with equivocal histological examination. However, their diagnostic value in this setting remains to be proven.

Topics: Adenoma; Adult; Carcinoma; Cyclin D1; DNA, Neoplasm; Female; Humans; Immunohistochemistry; Loss of Heterozygosity; Male; Middle Aged; Parathyroid Neoplasms; Predictive Value of Tests; Sensitivity and Specificity; Sequence Analysis, DNA; Tumor Suppressor Proteins

The identification of the specific molecular targets, which underlie liver carcinogenesis is essential for the establishment of an effective strategy for the prevention and/or treatment of hepatocellular carcinomas (HCCs). We previously found that a malfunction of RXRalpha due to its aberrant phosphorylation was associated with the development of HCCs. However, it has remained unclear whether the abnormalities in the expression of RXRalpha or the other retinoid receptors play a role in the early stage of liver carcinogenesis. The present study was designed to determine whether alterations in the expression of RXRalpha and the other retinoid receptors RARalpha and RARbeta are involved in hepatocarcinogenesis using a 3'-methyl-4-dimethylaminoazobenzene (3'-MeDAB)-induced rat liver carcinogenesis model. We found that immunohistochemical expression of RXRalpha was decreased in liver cell tumors (HCCs and adenoma) and glutathione S-transferase placental form (GST-P)-positive foci, which is a precancerous lesion of HCC, when compared with the non-cancerous tissues. Western blot and RT-PCR analyses revealed a progressive decrease in the expression levels of RXRalpha, RARalpha, and RARbeta proteins and their mRNAs in 3'-MeDAB-induced HCCs and their surrounding tissues, when compared with the normal liver tissues from the control group. Moreover, the expression level of beta-catenin, the heterodimeric partner for both RXRalpha and RARalpha, was immunohistochemically observed in the cytoplasm and, in some cases, in the nucleus of HCC cells. The nuclear expression of cyclin D1, the downstream target molecule of beta-catenin, was also increased in HCC cells when compared with their adjacent normal appearing tissues. Our findings suggest that loss of retinoid receptors, especially RXRalpha, plays a critical role in the chemically-induced rat liver carcinogenesis and this might be associated with the activation of beta-catenin-related signaling pathway.

Topics: Adenoma; Animals; beta Catenin; Blotting, Western; Carcinoma, Hepatocellular; Cell Nucleus; Cyclin D1; Gene Expression Regulation, Neoplastic; Glutathione S-Transferase pi; Immunoenzyme Techniques; Liver Neoplasms, Experimental; Male; Methyldimethylaminoazobenzene; Rats; Rats, Inbred F344; Receptors, Retinoic Acid; Retinoic Acid Receptor alpha; Retinoid X Receptor alpha; Reverse Transcriptase Polymerase Chain Reaction; RNA, Messenger

Differentiated thyroid cancer (DTC) generally has a favorable outcome, but some patients develop local recurrence and/or distant metastases and ultimately die of their disease. Molecular markers that accurately predict tumor behavior are lacking. This study's aim was to ascertain the role of cell cycle regulators in predicting malignant histology and tumor behavior in DTC.. Tissue microarrays consisting of 100 benign and 105 malignant thyroid lesions, plus 24 lymph node samples, were stained for p16, p21, p27, p53, p57, p63, cyclin D1, cyclin E, and mdm2. Statistical analysis was used to compare the expression of the markers in benign versus DTC lesions and correlate their expression with clinicopathologic characteristics.. p16, p21, cyclin D1, and cyclin E showed significantly (P < .001) increased expression in DTCs compared with benign thyroid lesions (54.7% vs. 5%, 71.7% vs. 38%, 87.1% vs. 45.7%, and 72.3% vs. 37.4%, respectively). There was no significant difference in expression between benign lesions and DTC for the remaining markers. p16 expression correlated significantly with extrathyroidal tumor extension (P = .02) and the presence of cancer in lymph nodes (P = .03). A total of 73% vs. 45% of the cancers of patients with and without lymph node involvement, respectively, stained positive for p16 (P = .01).. There is a statistically significant difference in the expression of p16, p21, cyclin D1, and cyclin E between DTCs and benign thyroid lesions, and p16 expression correlates with clinicopathologic variables predicting poor outcomes for DTC. These results suggest that evaluation of cell cycle derangement in thyroid tumors may serve as a useful tool for both DTC diagnosis and prognosis.

Topics: Adenoma; Adolescent; Adult; Aged; Aged, 80 and over; Carcinoma, Papillary; Cell Cycle; Cell Cycle Proteins; Cell Differentiation; Cyclin D1; Cyclin E; Cyclin-Dependent Kinase Inhibitor p21; Cyclin-Dependent Kinase Inhibitor p27; Cyclins; Female; Humans; Immunoenzyme Techniques; Lymphatic Metastasis; Male; Medical Records; Middle Aged; Oxyphil Cells; Prognosis; Prospective Studies; Thyroid Neoplasms; Tissue Array Analysis; Tissue Fixation; Tumor Suppressor Proteins

The abnormal oncogenes and antioncogenes in Wnt signaling transduction pathway activate downstream specific target genes, and may play important roles in tumorigenesis and tumor progression. This study was to examine the expression of adenomatous polyposis coli (APC), beta-catenin, C-myc, and Cyclin D1 in different colorectal tissues, and investigate their possible roles in the carcinogenesis of colorectal carcinoma.. The expression of APC, beta-catenin, C-myc, and Cyclin D1 in 30 specimens of normal colorectal mucosa, 30 specimens of colorectal adenoma, 10 specimens of colorectal adenoma with malignancy, and 50 specimens of colorectal carcinoma was examined by immunohistochemistry. The expression of beta-catenin on cell membrane was regarded as normal, and its expression in cytoplasm and nuclei was defined as ectopic expression.. The positive rate of APC was significantly lower in colorectal carcinoma and colorectal adenoma with malignancy than in colorectal adenoma and normal colorectal mucosa (44.0% and 40.0% vs. 86.7% and 100.0%, P<0.01). The ectopic expression rate of beta-catenin was significantly higher in colorectal carcinoma, colorectal adenoma with malignancy, and colorectal adenoma than in normal colorectal mucosa (62.0%, 50.0%, and 30.0% vs. 0%, P<0.01), and significantly higher in colorectal carcinoma than in colorectal adenoma (P<0.01). The positive rate of C-myc was significantly higher in colorectal carcinoma, colorectal adenoma with malignancy, and colorectal adenoma than in normal colorectal mucosa (56.0%, 60.0%, and 46.7% vs. 0%, P<0.01). The positive rate of Cyclin D1 was significantly higher in colorectal carcinoma, colorectal adenoma with malignancy, and colorectal adenoma than in normal colorectal mucosa (66.0%, 60.0%, and 30.0% vs. 0%,P<0.01), and significantly higher in colorectal carcinoma than in colorectal adenoma (P<0.01). The ectopic expression of beta-catenin was positively correlated to the expression of C-myc and Cyclin D1 (r=0.63,P<0.01; r=0.57, P<0.01), and negatively correlated to the expression of APC (r=-0.39, P<0.05).. The reduced expression of APC, ectopic expression of beta-catenin, overexpression of C-myc and Cyclin D1 exist in colorectal carcinoma, which may play important roles in the carcinogenesis of colorectal carcinoma.

Topics: Adenocarcinoma; Adenoma; Adenomatous Polyposis Coli Protein; beta Catenin; Colorectal Neoplasms; Cyclin D1; Gene Expression Regulation, Neoplastic; Humans; Immunohistochemistry; Intestinal Mucosa; Precancerous Conditions; Proto-Oncogene Proteins c-myc

Gallbladder adenomas are infrequent neoplasms whose relation to adenocarcinoma is not well understood. It has been suggested that adenomas and adenocarcinomas follow different molecular pathways.. This is a comparative, cross-sectional study in which we compared p53 and D1 cyclin expression in adenomas and adenocarcinomas of the gallbladder.. We included 12 cases in each group. Expression of p53 occurred in 83.3% of adenocarcinomas and in 16.6% of adenomas (p = 0.003). D1 cyclin was expressed in a similar number of adenomas and adenocarcinomas.. Our results support the hypothesis that p53 is an important step in the pathogenesis of adenocarcinomas but not of adenomas of the gallbladder. D1 cyclin is apparently a common pathway involved in the genesis of both tumors.

Topics: Adenoma; Adult; Cross-Sectional Studies; Cyclin D1; Female; Gallbladder Neoplasms; Humans; Male; Tumor Suppressor Protein p53

To analyze the cell kinetics of ulcerative colitis (UC)-associated dysplasia, cyclin A, cyclin D1, cyclin E, cdk2, cdk4, p21(Waf1), and p27(Kip1) were immunohistochemically examined, in comparison with sporadic tubular adenomas. Immunohistochemical labeling indices for each marker in formalin-fixed paraffin-embedded tissue sections were assessed in a total of 23 low-grade dysplasias, 27 high-grade dysplasias, and 14 invasive adenocarcinomas associated with UC. For comparison, 21 sporadic tubular adenomas with low-grade dysplasia, 33 with high-grade dysplasia, and 21 invasive adenocarcinomas were also examined. In UC-associated dysplasias, cyclin A and p27(Kip1) were located in the lower parts of the crypts and p21(Waf1) in the upper regions. In tubular adenomas, cyclin A, cdk4, p27(Kip1), and p21(Waf1) were all expressed in the upper parts of the crypts. The expression levels of cyclin D1, cyclin E, and cdk2 were low. The cell proliferation zone in UC-associated dysplasia is located towards the bases of the crypts with the strong expression of cyclin A and p27(Kip1), in contrast to tubular adenomas, which have their cell proliferation zone in the upper parts of neoplastic crypts. It is considered that tumorigenesis with UC-associated dysplasia is of the bottom-up type, related to altered expression of cyclin A and p27(Kip1).

Topics: Adenoma; Cell Proliferation; Colitis, Ulcerative; Colorectal Neoplasms; Cyclin A; Cyclin D1; Cyclin-Dependent Kinase 2; Cyclin-Dependent Kinase 4; Cyclin-Dependent Kinase Inhibitor p21; Cyclin-Dependent Kinase Inhibitor p27; Cyclin-Dependent Kinases; Intracellular Signaling Peptides and Proteins; Models, Biological

Dysregulation of the centrosome complex and chromosomal segregation has been associated with aneuploid cells and aggressive solid tumours, but the relevance of this mechanism to the adenoma-carcinoma sequence of sporadic colorectal cancer (sCRC), especially tumours showing chromosomal instability (CIN), is still unknown. In a series of matching normal epithelial cells (n = 41), dysplastic cells (n = 18), and invasive carcinoma cells (n = 41) from cases with sCRC, mRNA levels of the centrosomal kinase Aurora-A/STK15 and the chromosomal passenger- and cell cycle-associated molecules Incenp, Survivin, Mad-2, and Cyclin-D1 were therefore measured with specific reference to the type of genetic instability. Compared with normal epithelium, significant up-regulation of mRNAs was already present for Aurora-A/STK15 (p = 0.0313) in dysplastic cells and for all investigated markers in invasive carcinoma. Whereas Aurora-A/STK15 mRNA levels were similarly up-regulated in dysplastic and invasive carcinoma cells (p = 0.0797), Survivin (p = 0.0046) and Cyclin-D1 (p = 0.0017) mRNA levels increased from dysplastic to invasive carcinoma cells. In carcinomas, Incenp mRNA correlated with T category (p = 0.0149), and Survivin (p = 0.0382) and Cyclin-D1 (p = 0.0185) were associated with tumour differentiation. Importantly, a significantly higher (p = 0.0419) fold-change of Aurora-A/STK15 mRNA (p = 0.0419), but not Incenp, Survivin, Mad-2 or Cyclin-D1, was observed in sCRC cases with CIN (n = 29) when compared with tumours showing microsatellite instability (MIN, n = 10). The present data are the first to show an early increase of the centrosomal kinase Aurora-A/STK15 in the adenoma-carcinoma sequence of sCRC. The regulation of this kinase differs in CIN- and MIN-type sCRCs and the pattern of changes is different from those of the cell-cycle-associated markers Survivin, Mad-2, and Cyclin-D1. This reinforces the concept of preferential dysregulation of the centrosome complex in CIN-type (aneuploid), compared with MIN-type, sporadic colorectal cancers and may influence the response to and efficiency of novel therapeutics targeting Aurora kinases.

Topics: Adenoma; Adult; Aneuploidy; Aurora Kinase A; Aurora Kinases; Calcium-Binding Proteins; Carcinoma; Case-Control Studies; Cell Cycle; Cell Cycle Proteins; Centrosome; Chromosomal Proteins, Non-Histone; Colorectal Neoplasms; Cyclin D1; Disease Progression; Epithelial Cells; Female; Gene Expression Regulation, Neoplastic; Genetic Markers; Humans; Immunohistochemistry; Inhibitor of Apoptosis Proteins; Mad2 Proteins; Male; Microsatellite Repeats; Microtubule-Associated Proteins; Neoplasm Proteins; Precancerous Conditions; Protein Serine-Threonine Kinases; Repressor Proteins; Reverse Transcriptase Polymerase Chain Reaction; RNA, Messenger; Statistics, Nonparametric; Survivin

Abrogation of the Wnt-signaling pathway is implicated in the carcinogenesis of several malignancies, especially colorectal cancer where up to 90% of cases are thought to have impaired Wnt signaling. It is less frequently involved in conventional ductal pancreatic adenocarcinoma. This pathway has not been explored in intraductal papillary mucinous neoplasms (IPMNs) of the pancreas previously and formed the basis of this study. A tissue microarray of 18 cases of IPMN was stained for proteins involved in the Wnt pathway: adenomatous polyposis coli (APC), pan-beta-catenin, axin 2, glycogen synthase 3alphabeta and 3beta, c-myc, E-cadherin, and cyclin D1. The IPMNs were classified as 8 adenomas, 3 borderline, and 7 cases with carcinoma in situ and/or invasive carcinoma, occurring in 13 females, and the overall age range was 45 to 73 years. Immunohistochemical analysis showed nuclear beta-catenin staining in 7 (39%) of the 18 cases. The cases with nuclear beta-catenin localization included 1 adenoma, 2 borderline IPMN, and 4 carcinomas in situ and/or invasive carcinomas. Seven cases showed absence of APC immunostaining and these included 4 cases with nuclear beta-catenin localization. Fourteen cases displayed marked diffuse up-regulation of c-myc protein, and 12 cases also showed diffuse cyclin D1 protein overexpression. E-cadherin expression was intense and membrane in location (comparable to normal tissue) in 6 of 8 adenomas (no tissue was available in 1 case). Decreased E-cadherin staining was noted in 8 cases where tissue was available for assessment. There was progressive decrease in membrane staining of E-cadherin in 2 of 3 borderline lesions, 1 of 2 carcinomas in situ, and 4 of 5 invasive carcinomas. All other immunostains were either normal in distribution or did not show any correlation with beta-catenin or clinicopathologic parameters. In conclusion, 7 (39%) of 18 cases of IPMN in this study demonstrated abnormal localization of beta-catenin, 4 of which also lacked APC expression. Of 5 carcinomas arising in IPMN, 4 displayed a decrease in E-cadherin expression. There was also a trend for the higher grades of IPMN to show nuclear localization of beta-catenin. These findings suggest that a proportion of cases of IPMN may show abnormalities in the Wnt-signaling pathway with consequent altered expression of downstream related proteins.

Topics: Adenoma; Aged; beta Catenin; Cadherins; Carcinoma in Situ; Carcinoma, Pancreatic Ductal; Cyclin D1; Female; Humans; Immunohistochemistry; Male; Middle Aged; Pancreatic Neoplasms; Protein Array Analysis; Proto-Oncogene Proteins c-myc; Wnt Proteins

Cyclin D1 (CCND1) plays a key role in cell cycle control, particularly in the transition from G1 to S phase, which is regulated by cyclin-dependent kinases. A common adenine to guanine polymorphism (A870G) in the CCND1 gene has been associated with a longer-life protein and an increased risk of colorectal cancer and adenoma in some studies. Among subjects with hereditary nonpolyposis colorectal cancer, the A870G polymorphism has also been associated with a younger age of onset of colorectal cancer. We analysed 181 colorectal cancer cases and 475 matched controls and 524 adenoma cases and 517 matched controls within women in the Nurses' Health Study (NHS) cohort, 171 colorectal cancer cases and 347 matched controls and 372 adenoma cases and 712 matched controls nested within men in the Health Professionals' Follow-Up Study (HPFS) cohort, and 258 colorectal cancer cases and 415 matched controls within men in the Physicians' Health Study (PHS) cohort to assess the risk associated with the CCND1 A870G genotype. Moreover, we assessed whether CCND1 genotype modified the effect of a sporadic (nonsyndromic) family history of colorectal cancer as well as the effect of other dietary and lifestyle risk factors for colorectal cancer and adenoma. In all cohorts combined, the CCND1 polymorphism did not show statistically significant associations to risk of colorectal cancer (odds ratio (OR) for A allele carriers, 1.04; 95% confidence interval (95% CI), 0.82-1.32) or adenoma (OR, 0.96; 95% CI, 0.79-1.18). The CCND1 A870G genotype was associated with a modest, although nonsignificantly elevated risk of colorectal cancer (OR, 1.59; 95% CI, 0.98-2.57) in women. In contrast, the polymorphism was not associated with increased risk of adenoma in either men or women. Among participants with the A870G genotype, a family history of colorectal cancer conferred a substantially greater risk of colorectal cancer in the women (P for interaction=0.06) and adenoma in the men (P for interaction=0.02). Current postmenopausal hormone (PMH) use was associated with a significant reduction in the risk of colorectal cancer and adenoma among women with the A870G genotype, whereas there was no effect of PMH use among those with the GG genotype. The CCND1 polymorphism appeared to confer a modest elevation in the risk of colorectal cancer among women. Moreover, the A870G genotype may enhance the protective effect of postmenopausal oestrogen use on the development of colorectal neoplasia.

Topics: Adenoma; Adult; Case-Control Studies; Colorectal Neoplasms; Cyclin D1; Diet; Female; Genotype; Humans; Life Style; Middle Aged; Polymorphism, Genetic; Risk Factors

Inactivation of the hyperparathyroidism-jaw tumour syndrome (HPT- JT) gene, HRPT2, was recently established as a genetic mechanism in the development of parathyroid tumours. Its encoded protein parafibromin has tumour-suppressor properties that play an important role in tumour development in the parathyroids, jaws and kidneys. Inactivating HRPT2 mutations are common in HPT- JT and parathyroid carcinomas, and have been described in a few cases of parathyroid adenomas with cystic features. In this study, 46 cases of cystic parathyroid adenomas previously investigated for HRPT2 mutations were characterized with regard to MEN1 gene mutations, cyclin D1 expression and parafibromin expression. In normal tissues and cell lines, parafibromin was ubiquitously expressed. Furthermore, parafibromin was detected as a dominating nuclear and a weaker cytoplasmic signal in transfected cell lines. In the three parathyroid tumours with inactivating HRPT2 mutations parafibromin expression was not detectable, and in one of two cases with aberrantly sized parafibromin the protein was delocalized. Both high and low cyclin D1 levels were found among HRPT2-mutated and -unmutated tumours, suggesting that these events are not mutually exclusive in parathyroid tumour development. The presented data suggest that in the majority of benign parathyroid tumours the expression of parafibromin remains unaltered, while the loss of parafibromin expression is strongly indicative of gene inactivation through mutation of the HRPT2 gene.

Topics: Adenoma; Adult; Aged; Animals; Chlorocebus aethiops; COS Cells; Cyclin D1; Female; HeLa Cells; Humans; Immunohistochemistry; Loss of Heterozygosity; Male; Middle Aged; Mutation; Parathyroid Neoplasms; Proto-Oncogene Proteins; RNA, Messenger; Tumor Suppressor Proteins

Colorectal carcinogenesis is initiated mainly by aberrant activation of the Wnt signaling pathway, caused by mutation of either APC or beta-catenin (CTNNB1) gene. Poly(ADP-ribose) polymerase-1 (PARP-1) is a highly conserved nuclear enzyme, which binds tightly to DNA and plays a role in DNA repair, recombination, proliferation and genomic stability. It has recently been shown that PARP-1 is a novel co-activator of TCF-4/beta-catenin-evoked gene transactivation and may play a role in colorectal carcinogenesis. The aim of this study was to examine the PARP-1 expression and determine whether it is correlated with the expression of beta-catenin and its target genes such as c-myc, cyclin D1 and matrix metalloproteinase (MMP)-7 in the early stage of sporadic colorectal carcinogenesis. Using the semi-quantitative reverse transcriptase-polymerase chain reaction (RT-PCR), 91 colorectal tumours, including 65 adenomas and 26 submucosal (pT1) cancers, were analysed for the expression of PARP-1, beta-catenin, c-myc, cyclin D1 and MMP-7. Immunohistochemical analysis of PARP-1 and beta-catenin was also performed. PARP-1 mRNA overexpression was detected in 64 (70.3%) of the 91 tumours. PARP-1 overexpression was significantly correlated with tumour size and histopathology. Overexpression of beta-catenin, c-myc, cyclin D1 and MMP-7 mRNA expression was observed in 39.6%, 78.0%, 83.5% and 72.5% of the 91 tumours, respectively. PARP-1 overexpression was correlated significantly with overexpression of beta-catenin, c-myc, cyclin D1 and MMP-7. Correlation of PARP-1 expression with beta-catenin overexpression was also demonstrated by immunohistochemistry. The results suggest that PARP-1, in conjunction with beta-catenin, c-myc, cyclin D1 and MMP-7, plays an important role in the early stage of colorectal carcinogenesis.

Topics: Adenocarcinoma; Adenoma; beta Catenin; Colorectal Neoplasms; Cyclin D1; Female; Genes, myc; Humans; Immunohistochemistry; Male; Matrix Metalloproteinase 7; Middle Aged; Poly (ADP-Ribose) Polymerase-1; Poly(ADP-ribose) Polymerases; Proto-Oncogene Proteins c-myc; Reverse Transcriptase Polymerase Chain Reaction; RNA, Messenger; RNA, Neoplasm

Tissue microarray (TMA) holds promise as a high-throughput method for the analysis of biomarkers in tissue specimens. The validity and reliability of this method, however, may vary for different biomarkers in different tissue specimens.. In this study, we evaluated the validity and reliability of using TMA to assess biomarkers in colorectal adenomas.. Sixty-three consecutive patients with colorectal adenomas were recruited in this study. Two TMA blocks were constructed using four punches from each adenoma (one periphery, one deep, and two middle zones). The immunostaining of five markers (Ki-67, cyclin D1, beta-catenin, cyclooxygenase-2, and epidermal growth factor receptor) was analyzed, and the concordance between data obtained from TMAs and standard whole-tissue sections was evaluated by Spearman's correlation and kappa analysis.. Colorectal adenoma exhibited zonal, heterogeneous expression patterns for all five markers. The concordance rates for the semiquantitative evaluation of markers between data from TMAs and whole sections ranged from 87% to 93% with corresponding kappa statistics of 77% to 90%. In addition, both quantitative and semiquantitative methods were used to score TMA sections, and good correlations between these two methods were shown for all five markers with intraclass correlation coefficients ranging from 0.5 to 0.8.. Our study indicates that TMA can be used to reliably assess the expression levels of Ki-67, cyclin D1, beta-catenin, cyclooxygenase-2, and epidermal growth factor receptor in colorectal adenoma tissues.

Topics: Adenoma; Aged; beta Catenin; Colorectal Neoplasms; Cyclin D1; Cyclooxygenase 2; ErbB Receptors; Female; Humans; Immunohistochemistry; Ki-67 Antigen; Male; Middle Aged; Tissue Array Analysis

Parafibromin is the 531-amino-acid protein product encoded by HRPT2, a putative tumor suppressor gene recently implicated in the autosomal dominant hyperparathyroidism-jaw tumor familial cancer syndrome, sporadic parathyroid cancer, and a minority of families with isolated hyperparathyroidism. Parafibromin contains no identified functional domains but bears sequence homology to Cdc73p, a budding yeast protein component of the RNA polymerase II-associated Paf1 complex. This study addressed the expression and functional properties of human parafibromin. A survey of human and mouse tissues analysed with polyclonal antibodies to parafibromin showed specific immunoreactivity in adrenal and parathyroid glands, kidney, heart, and skeletal muscle. Subcellular fractionation and laser confocal microscopy of normal human parathyroid gland demonstrated expression of parafibromin in both the cytoplasmic and nuclear compartments. Parafibromin was expressed in four parathyroid adenomas but was absent from two parathyroid carcinomas. Transient overexpression of wild-type parafibromin, but not its Leu64Pro missense mutant implicated in parathyroid cancer and familial isolated hyperparathyroidism, inhibited cell proliferation, and blocked expression of cyclin D1, a key cell cycle regulator previously implicated in parathyroid neoplasia. These results demonstrate that human parafibromin is a nucleocytoplasmic protein with functions consistent with its postulated role as a tumor suppressor protein.

Topics: Adenoma; Animals; Carcinoma; Cell Nucleus; Cell Proliferation; Chlorocebus aethiops; COS Cells; Cyclin D1; Cytoplasm; Down-Regulation; Humans; Mice; Mutation, Missense; Parathyroid Glands; Parathyroid Neoplasms; Proteins; Transfection; Tumor Suppressor Proteins

To investigate the role of cyclin D1, p16 and retinoblastoma in cancerous process of gallbladder carcinomas and to assess the relation between cyclin D1, p16, Rb and the biological characteristics of gallbladder carcinoma.. Forty-one gallbladder carcinoma, 7 gallbladder adenoma and 14 chronic cholecystitis specimens were immunohistochemically and histopathologically investigated for the relation of cyclin D1, p16 and Rb with Nevin staging and pathologic grading.. The expression rates of abnormal cyclin D1 in gallbladder carcinoma (68.3%) and gallbladder adenoma (57.1%) were significantly higher than those in chronic cholecystitis (7.1%) (P<0.05). No significant difference was found both among the pathological grades G(1), G(2) and G(3) and among Nevin stagings S(1)-S(2), S(3) and S(4)-S(5) of gallbladder carcinoma. The positive rates of p16 (48.8%) and Rb (58.5%) in gallbladder carcinoma were significantly lower compared to those in adenoma (100.0%) and cholecystitis (100.0%) (P<0.05). The positive rates of p16 and Rb in Nevin stagings S(1)-S(2) (80.0% and 90.0%) and S(3) (46.2% and 61.5%) gallbladder carcinomas were significantly higher than those in S(4)-S(5) (33.3% and 38.8%) (P<0.05), and those in pathologic grades G(1) (54.5% and 81.8%) and G(2) (50.0% and 62.5%) gallbladder carcinoma were significantly higher than those in G(3) (28.6% and 35.7%) (P<0.05). The protein expression of p16 and Rb had a negative-correlation in gallbladder carcinoma (r = -0.2993, P<0.05), and this negative-correlation was correlated with Nevin staging (P<0.05). Moreover, the protein expression of p16 and cyclin D1 had a negative-correlation in gallbladder carcinoma (r = -0.9417, P<0.05).. Cyclin D1 may play a role in the early stage of gallbladder carcinoma. Mutation of p16 and Rb genes might be correlated with progression of gallbladder carcinoma. Analysis of p16 and Rb can estimate the prognosis of gallbladder carcinoma. Expression of p16 and Rb may be correlated with Nevin staging and pathologic grading in gallbladder carcinoma.

Topics: Adenoma; Carcinoma; Cholecystitis; Cyclin D1; Cyclin-Dependent Kinase Inhibitor p16; Gallbladder Neoplasms; Humans; Immunoenzyme Techniques; Mutation; Neoplasm Staging; Prognosis; Retinoblastoma Protein

Somatic deletion of chromosome 11q13 is the most frequent genetic aberration in parathyroid adenoma. To gain further insight into the genetic etiology of parathyroid tumor development, we examined a comprehensive gene expression profile of parathyroid adenomas and normal parathyroid tissues. The results were then evaluated with respect to differences between adenomas and normal parathyroid tissue, and to the presence of loss of heterozygosity (LOH) in chromosomal region 11q13.. Sporadic parathyroid adenomas and normal parathyroids were hybridized against HG-U95Av2 oligonucleotide arrays (Affymetrix) containing a total of 12,625 probe sets. Quantitative real-time PCR (QRT-PCR) was performed in a larger series of parathyroid adenomas, in order to con-firm the microarray results.. Cyclin D1 and c-Jun showed increased expression in adenomas vs normal parathyroids by microarray analysis and QRT-PCR, suggesting an oncogenic role of these genes in parathyroid tumor development. At unsupervised hierarchical clustering, the adenomas fell into two groups: Group I adenomas were characterized by 11q13 LOH, while Group II adenomas lacked this abnormality. In addition, a t-test analysis identified largely non-overlapping genes with differential expression in the tumors subgroups; e.g. in Group I tumors the putative oncogene ENC 1 was found highly over-expressed vs Group II adenomas.. The microarray analyses revealed partly distinctive and partly common expression profiles in parathyroid adenomas with and without 11q13 LOH. In addition, approximately half of the under-expressed genes were mapped to chromosome 11, in agreement with a dose effect following loss of this chromosome.

Topics: Adenoma; Adult; Aged; Aged, 80 and over; Case-Control Studies; Chromosomes, Human, Pair 11; Cyclin D1; Female; Gene Expression; Gene Expression Profiling; Genes, jun; Humans; Loss of Heterozygosity; Male; Microarray Analysis; Middle Aged; Multigene Family; Parathyroid Neoplasms; Reverse Transcriptase Polymerase Chain Reaction

Protein products of cyclin D1 and retinoblastoma (Rb) genes play crucial roles in regulation of G1/S transition in the cell cycle. In this study we analyzed, using immunohistochemical methods, the expression of cyclin D1 and Rb proteins in material from medical archives (12 cases of follicular thyroid carcinoma, 57 cases of follicular adenoma and 17 nodular goiter cases). A positive nuclear reaction for cyclin D1 was observed in 83.3% (10/12) of the follicular carcinomas, in 96.5% (55/57) of the follicular adenomas and in 23.5% (4/17) of nodular goiters. Overexpression of cyclin Dl (more than 50% of positively staining cells) was noted in 25% (3/12) of the follicular carcinomas and in 22.8% (13/57) of the follicular adenomas. No overexpression of cyclin D1 was noted among nodular goiters. The number of carcinoma cases with cyclin D1 overexpression did not differ statistically in any significant way from the follicular adenoma group (p = 1.000). A positive nuclear reaction for Rb protein was noted in 100% of the follicular carcinomas (12/12), in 96.5% of the follicular adenomas (55/57) and in 47.1% of the cases (8/17) of nodular goiter. Rb protein overexpression (more than 50% of positively staining cells) was found in 83.3% (10/12) of the follicular carcinomas, in 68.4% (39/57) of the follicular adenomas and in 11.8% (2/17) of the nodular goiters. The number of cases with Rb protein overexpression in the follicular carcinoma group did not differ significantly from that in the follicular adenoma group (p = 0.486). A positive correlation was found in the groups studied between the expressions of Rb protein and cyclin D1. However, the correlation was statistically significant only in the nodular goiter group (Rs = 0.567; p = 0.018). In the follicular carcinoma group, that correlation was borderline (Rp = 0.437; p = 0.072) and, in the follicular adenoma group, it was statistically insignificant (Rs = 0.217; p = 0.105). Our results confirm the existence of mutual regulation mechanisms of Rb and cyclin D1 protein expressions, which are observed in cells from various carcinomas.

Topics: Adenocarcinoma, Follicular; Adenoma; Biomarkers, Tumor; Cyclin D1; Goiter, Nodular; Humans; Retinoblastoma Protein; Thyroid Neoplasms

Cyclin D1 is postulated to be a target of the canonical Wnt pathway and critical for intestinal adenoma development. We show here that, unlike cyclin D1 reporter assays, endogenous cyclin D1 levels are not affected following antagonism of the Wnt pathway in vitro, nor is cyclin D1 immediately up-regulated following conditional loss of Apc in vivo. Cyclin D1 levels do, however, increase in a delayed manner in a small subset of cells, suggesting such up-regulation occurs as a secondary event. We also analyzed the immediate consequences of Apc loss in a cyclin D1(-/-) background and failed to find any cyclin D1-dependent phenotypes. However, we did observe elevated cyclin D1 expression in lesions developing 20 days after Apc loss. In these circumstances, all adenomas (but not smaller lesions) showed cyclin D1 up-regulation. Finally in a smaller study, we analyzed whether cyclin D1 deficiency affected adenoma formation 20 days following induced loss of Apc. Unlike AhCre(+) Apc(fl/fl) mice (which all developed adenomas), doubly mutant AhCre(+) Apc(fl/fl) cyclin D1(-/-) mice only developed small lesions. Taken together, this argues that cyclin D1 up-regulation in intestinal neoplasia is important for tumor progression rather than initiation.

Topics: Adenoma; Animals; beta Catenin; Cell Line, Tumor; Colorectal Neoplasms; Cyclin D1; Cytoskeletal Proteins; Gene Deletion; Gene Expression Regulation, Neoplastic; Genes, APC; Integrases; Intestinal Neoplasms; Mice; Mice, Inbred C57BL; Phenotype; Trans-Activators

We have earlier shown that dietary fructo-oligosaccharide inulin enhances adenoma growth in multiple intestinal neoplasia (Min/+) mice. To further explore inulin-induced early biochemical changes in the normal-appearing mucosa, Min/+ mice were fed from the age of 5 weeks to the ages of 8 and 15 weeks a control diet or an inulin-enriched diet (10% w/w). In addition, the wild-type littermates were fed with the same diets until the age of 8 weeks, in order to determine whether similar changes happen both in the wild-type and Min/+ mice. The mucosa without adenomas was collected and fractionated to nuclear, cytosolic and membrane pools. The protein levels of beta-catenin, cyclin D1 and E-cadherin were determined by Western blotting at both time points, and immunohistochemical stainings were done for 8-week-old mice. The promotion of adenoma growth by inulin (week 15, 1.3-fold increase, P=.0004) was associated with accumulation of cytosolic and nuclear beta-catenin, and increased amount of cytosolic cyclin D1 (1.5-fold increase, P=.003) in the normal-appearing mucosa of the Min/+ mice. Furthermore, inulin feeding reduced the membranous pools of beta-catenin and E-cadherin. Also in the wild-type mice the drop in membranous beta-catenin was clear (P=.015), and, moreover, a subset of crypts had enhanced nuclear beta-catenin staining. These data indicate that dietary inulin can already activate in the normal-appearing mucosa beta-catenin signaling, which in the presence of Apc mutation induces adenoma growth and even in the wild-type mice direction of the changes is similar.

Topics: Adenoma; Animals; beta Catenin; Cadherins; Cyclin D1; Cytoskeletal Proteins; Cytosol; Diet; Female; Intestinal Mucosa; Intestinal Neoplasms; Inulin; Male; Mice; Mice, Inbred C57BL; Mice, Mutant Strains; Signal Transduction; Trans-Activators; Weight Gain

Alterations in cAMP signaling have been identified as a cause of endocrine neoplasia. In particular, activating mutations of the G(s)alpha gene and protein kinase A (PKA) overactivity due to low expression of PKA regulatory subunit 1A (R1A) have been implicated in somatotroph proliferation.. The objective of this study was to evaluate the effects of cAMP-PKA cascade activation in nonfunctioning pituitary adenomas (NFPA).. By immunohistochemistry, R1A, R2A, and R2B expression was evaluated in cells obtained from eight surgically removed NFPA positive for gonadotropins. Cyclin D1 expression and ERK1/2 activity were analyzed under basal conditions and after cAMP-PKA cascade activation.. Immunohistochemistry studies demonstrated a low R1/R2 ratio in all NFPA. Additional unbalance of R1/R2 ratio by 8-chloroadenosine cAMP (8-Cl-cAMP) and direct adenylyl cyclase stimulation by forskolin did not increase cyclin D1 expression or ERK1/2 activity in five NFPA (group 1), but even caused 74 +/- 15% and 85 +/- 13% inhibitions of cyclin D1 and ERK1/2 activity, respectively, in the remaining NFPA (group 2). Moreover, in group 2, PKA blockade by the specific inhibitor PKI increased cyclin D1 expression (96 +/- 25% over basal) and ERK1/2 activity (116 +/- 28% over basal).. These data show that in contrast with what was previously observed in transformed somatotrophs, activation of the cAMP-PKA pathway did not generate proliferative signals in tumoral cells of the gonadotroph lineage, and in a subset of tumors even exerted a tonic inhibitory effect, thus confirming a different role for the cAMP-mediated pathway in promoting proliferation in the pituitary.

Topics: Adenoma; Base Sequence; Biomarkers, Tumor; Cell Proliferation; Cyclic AMP; Cyclic AMP-Dependent Protein Kinase RIalpha Subunit; Cyclic AMP-Dependent Protein Kinases; Cyclin D1; Enzyme Activation; Humans; In Vitro Techniques; Mitogen-Activated Protein Kinase 1; Mitogen-Activated Protein Kinase 3; Pituitary Neoplasms; Proteins; Receptors, Cell Surface

Malignant transformation of parathyroid tumours is rare. Nevertheless, this small subset of malignant tumours often creates diagnostic and therapeutic problems. In this work, the morphological characteristics of 26 primary parathyroid carcinomas and seven metastases have been studied. Furthermore, immunohistochemical expression profiles for the calcium sensing receptor (CASR), cyclin D1 (CCND1), and Ki-67 were determined for parathyroid carcinomas and compared with adenomas and hyperplasias using a tissue microarray. Loss of heterozygosity (LOH) of the chromosome 1q region containing the HRPT2 gene and chromosome 11q (MEN1) was determined in the carcinomas. In contrast to the adenomas and hyperplasias, 31% of carcinomas demonstrated down-regulation of CASR. A significant correlation was found between CASR expression and the Ki-67 proliferation index. Chromosome 1q and chromosome 11q LOH were found in 12 of 22 (55%) and 11 of 22 (50%) carcinomas tested, respectively. Combined 1q and 11q LOH was seen in 8 of 22 (36%) carcinomas, in contrast to the low percentage of LOH reported in both regions in adenomas. In conclusion, this study demonstrates that combined 1q and 11q LOH in parathyroid tumours is suggestive of malignant behaviour. Strong down-regulation of the CASR protein is seen in a proportion of parathyroid carcinomas with a high proliferation index.

Topics: Adenoma; Adult; Aged; Aged, 80 and over; Carcinoma; Chromosomes, Human, Pair 1; Chromosomes, Human, Pair 11; Cyclin D1; Female; Gene Expression Regulation, Neoplastic; Humans; Hyperplasia; Immunohistochemistry; Ki-67 Antigen; Loss of Heterozygosity; Lymphatic Metastasis; Male; Middle Aged; Oligonucleotide Array Sequence Analysis; Parathyroid Glands; Parathyroid Neoplasms; Receptors, Calcium-Sensing

Krüppel-like transcription factors have been linked to cell growth regulation and tumorigenesis in a number of systems. In the intestinal epithelium, expression of KLF5 (IKLF/BTEB2) is limited to proliferating crypt cells, indicating a growth-promoting role. Consistent with this role, we demonstrate that expression of KLF5 in non-transformed intestinal epithelial cells (ileal IEC-18 and Immorto-Min Colon Epithelial (IMCE) cells) enhances colony formation, cyclin D1 transcription, and cell growth. However, in contrast to these effects in non-transformed cells, KLF5 reduced colony number, failed to enhance cyclin D1 transcription, and was negatively correlated with cell growth in colon cancer cell lines. The relationship between tumor progression and KLF5 was further investigated using Ras-mediated transformation of IEC-18 and IMCE cells as syngeneic models. Ras-transformation recapitulated differences in the effects of KLF5 on cell growth and cyclin D1 transcription, providing a direct link between intestinal tumor progression and altered function of KLF5. Ras-transformation also markedly down-regulated KLF5; further analysis indicated that reduced expression of KLF5 mRNA and destabilization of KLF5 protein occur in intestinal tumors. Reduced levels of KLF5 mRNA were also detected in APC(min) mouse and human familial adenomatous polyposis adenomas compared with normal crypt epithelium, indicating that down-regulation of KLF5 is an early event in intestinal tumorigenesis in vivo. Collectively, these data indicate that intestinal tumor progression is associated with a change in the growth-related functions of KLF5 and that intestinal tumors down-regulate KLF5 expression by multiple mechanisms.

Topics: Adenoma; Animals; Blotting, Northern; Blotting, Western; Cell Division; Cell Line; Cell Line, Tumor; Cyclin D1; Disease Progression; Down-Regulation; Epithelial Cells; Flow Cytometry; Genes, Reporter; Humans; Ileum; Intestinal Neoplasms; Kruppel-Like Transcription Factors; Mice; Plasmids; Rats; Reverse Transcriptase Polymerase Chain Reaction; RNA, Messenger; RNA, Small Interfering; Trans-Activators; Transcription, Genetic

Follicular carcinomas account for 15% of thyroid malignant tumors. The differential diagnosis between adenoma and minimally invasive follicular carcinoma is difficult and lacks reproducibility especially in frozen sections. As the diagnosis depends on finding foci of capsular invasion, multiple sections must be examined. Numerous immunohistochemical markers have been studied for determining malignancy.. To assess the efficacy of HBME-1 and Cyclin-D1 as diagnostic markers for follicular thyroid carcinoma.. We evaluated retrospectively 21 thyroidectomy specimens of 18 women and 3 men with diagnosis of adenoma or follicular carcinomas, both by hematoxylin and eosin stain and by immunohistochemistry using the avidin biotin method for the markers HBME-1 and Cyclin D1.. The sensitivity and specificity of HBME-1 for the diagnosis of follicular thyroid carcinoma, were 88.9% and 100%, respectively whereas for Cyclin D1 the sensitivity and specificity were 22.2% and 100%, respectively. There were no false positive cases.. HBME-1 has excellent sensitivity and specificity for the diagnosis of follicular carcinoma.

Topics: Adenocarcinoma, Follicular; Adenoma; Adolescent; Adult; Biomarkers, Tumor; Cyclin D1; Diagnosis, Differential; Female; Humans; Male; Middle Aged; Retrospective Studies; Sensitivity and Specificity; Thyroid Neoplasms

The two regulatory subunits (R1 and R2) of protein kinase A (PKA) are differentially expressed in cancer cell lines and exert diverse roles in growth control. Recently, mutations of the PKA regulatory subunit 1A gene (PRKAR1A) have been identified in patients with Carney complex. The aim of this study was to evaluate the expression of the PKA regulatory subunits R1A, R2A, and R2B in a series of 30 pituitary adenomas and the effects of subunit activation on cell proliferation. In these tumors, neither mutation of PRKAR1A nor loss of heterozygosity was identified. By real-time PCR, mRNA of the three subunits was detected in all of the tumors, R1A being the most represented in the majority of samples. By contrast, immunohistochemistry documented low or absent R1A levels in all tumors, whereas R2A and R2B were highly expressed, thus resulting in an unbalanced R1/R2 ratio. The low levels of R1A were, at least in part, due to proteasome-mediated degradation. The effect of the R1/R2 ratio on proliferation was assessed in GH3 cells, which showed a similar unbalanced pattern of R subunits expression, and in growth hormone-secreting adenomas. The R2-selective cAMP analog 8-Cl cAMP and R1A RNA silencing, stimulated cell proliferation and increased Cyclin D1 expression, respectively, in human and rat adenomatous somatotrophs. These data show that a low R1/R2 ratio promoted proliferation of transformed somatotrophs and are consistent with the Carney complex model in which R1A inactivating mutations further unbalance this ratio in favor of R2 subunits. These results suggest that low expression of R1A protein may favor cAMP-dependent proliferation of transformed somatotrophs.

Topics: Adenoma; Cell Growth Processes; Cyclic AMP; Cyclic AMP-Dependent Protein Kinase RIalpha Subunit; Cyclic AMP-Dependent Protein Kinases; Cyclin D1; Enzyme Activation; Exons; Humans; Immunohistochemistry; Introns; Lysosomes; Pituitary Neoplasms; Proteasome Inhibitors; Protein Subunits; Proteins; Reverse Transcriptase Polymerase Chain Reaction; Tumor Cells, Cultured

We investigated the status of the components and target genes of the Wnt signaling pathway in Japanese anaplastic thyroid cancers (ATCs) in the present study. Nuclear and cytoplasmic positive staining of beta-catenin, which might indicate the existence of alterations in the Wnt signaling pathway, were found in 40.9% and 63.6% of the 22 ATC samples, respectively. The beta-catenin, adenomatous polyposis coli (APC) and Axin 1 gene mutations were observed in 4.5%, 9.0%, and 81.8% of the 22 ATC samples, respectively. Overexpression of cyclin D1 and c-myc, which are the target genes of the Wnt signaling pathway, was observed in 27.3% and 59.1% of the ATC samples, respectively. There was no significant correlation between nuclear or cytoplasmic positive staining of beta-catenin and nuclear positive staining of cyclin D1 or c-myc. Taken together, the results of beta-catenin immunohistochemistry suggest that alterations in the Wnt signaling pathway are associated with carcinogenesis of ATC, but the frequency of beta-catenin gene mutation in our series is lower than that previously reported. Furthermore, cyclin D1 and c-myc frequently accumulated in ATC, independently of dysfunction in the Wnt signaling pathway.

Topics: Adenoma; Aged; Aged, 80 and over; Axin Protein; beta Catenin; Carcinoma; Carcinoma, Papillary; Cyclin D1; Cytoskeletal Proteins; DNA, Neoplasm; Female; Genes, myc; Humans; Immunohistochemistry; Intercellular Signaling Peptides and Proteins; Japan; Male; Middle Aged; Mutation; Repressor Proteins; Signal Transduction; Thyroid Neoplasms; Trans-Activators; Wnt Proteins

Germline mutations in APC tumor suppressor gene are responsible for familial adenomatous polyposis (FAP). A major role of these genetic changes is the constitutive activation of beta-catenin-Tcf-4 mediated transcription of nuclear target genes, but other cellular functions can be misregulated. To assess how different APC mutations can drive the early steps of colonic tumorigenesis, we studied the effect of 10 different germline-truncating alterations on the phenotype of the corresponding adenomas. A significant reduction of apoptosis, uncoupled with an increased c-myc and cyclin-D1 expression, was seen with a frameshift mutation on codon 1383, in the 20-aa repeats of the beta-catenin degradation domain, independent of a somatic alteration on the wild-type allele. The decreased apoptotic level was associated with a higher incidence of cancerization. No other APC mutation was linked with a similar effect, even in presence of a somatic allelic loss. These findings suggest that mutations in critical sites of the beta-catenin degradation domain of APC gene can convey a selective advantage to the colonic neoplastic clones by altering the apoptotic surveillance rather than enhancing the beta-catenin-Tcf-4 transcription of growth-promoting genes.

Topics: Adenoma; Adenomatous Polyposis Coli; Adult; Apoptosis; beta Catenin; Colorectal Neoplasms; Cyclin D1; Cytoskeletal Proteins; DNA Mutational Analysis; DNA Primers; DNA, Neoplasm; Female; Genes, APC; Germ-Line Mutation; Humans; Immunohistochemistry; In Situ Nick-End Labeling; Male; Proto-Oncogene Proteins c-myc; Reverse Transcriptase Polymerase Chain Reaction; RNA, Neoplasm; Trans-Activators

The G protein-coupled receptor (GPCR) activation has been demonstrated to affect the ERK1/2 cascade in different cell lines. We investigated the effects of hypothalamic neuropeptides acting via GPCR on this pathway in GH-secreting (GH-oma) and nonsecreting (NFPA) pituitary adenomas. GHRH increased ERK1/2 activity (236 +/- 80%) in both gsp- and gsp+ GH-omas, this effect being almost completely abolished by protein kinase C (PKC) blockade. Both GnRH and pituitary adenylate-activating peptide caused a similar PKC-dependent activation of ERK1/2 in most NFPA. Increasing cAMP by forskolin caused a protein kinase A-dependent increase of ERK activity (287 +/- 37%) in GH-omas and had no effect in NFPA. ERK cascade blockade in GH-omas did not affect basal and GHRH-stimulated GH release, whereas it totally prevented the 3-fold increase in cyclin D1 protein expression induced by GHRH. In conclusion, this study demonstrated that in pituitary adenomas the activation of GPCR by neurohormones caused a PKC-dependent activation of ERK1/2 cascade that, at least in GH-omas, resulted to be involved in cyclin D1 induction by GHRH. Moreover, a stimulatory effect of the protein kinase A-dependent pathway on ERK1/2 cascade occurred selectively in GH-omas, probably contributing to the mitogenic potential of the cAMP pathway in this cell type.

Topics: Adenoma; Colforsin; Cyclic AMP; Cyclic AMP-Dependent Protein Kinases; Cyclin D1; Enzyme Inhibitors; Growth Hormone; Growth Hormone-Releasing Hormone; Heterotrimeric GTP-Binding Proteins; Humans; Hypothalamus; MAP Kinase Kinase 1; MAP Kinase Kinase 2; Mitogen-Activated Protein Kinase 1; Mitogen-Activated Protein Kinase 3; Mitogen-Activated Protein Kinase Kinases; Mitogen-Activated Protein Kinases; Neuropeptides; Phosphorylation; Pituitary Neoplasms; Protein Kinase C; Protein Serine-Threonine Kinases; Protein-Tyrosine Kinases; Tumor Cells, Cultured

To clarify kinetics in ulcerative colitis (UC)-associated lesions, cell proliferation, apoptosis, and expression of apoptosis-inhibitory proteins were studied. Ki-67 labeling and survivin and bcl-2 expression were examined immunohistochemically in 22 low-grade dysplasias (LGDs), 25 high-grade dysplasias (HGDs), and 13 adenocarcinomas associated with UC, and for comparison in 21 sporadic adenomas with LGD, 22 sporadic adenomas with HGD, and 21 invasive adenocarcinomas. Apoptosis was studied with nick-end labeling and immunohistochemical analysis of single-stranded DNA. In UC-associated LGDs, Ki-67--positive cells were more frequent in the lower than the upper half of the crypt, related to bcl-2 expression, while in sporadic adenomas such cells were more common in the upper half. No difference in apoptosis was found between UC-associated LGDs and sporadic adenomas with LGD or between UC-associated HGDs and sporadic adenomas with HGD. However, UC-associated carcinomas exhibited a lower apoptotic count than their sporadic invasive counterparts. This seemed related to higher survivin expression without a significant difference between the 2 types of invasive lesions regarding bcl-2 levels. Apoptosis is less frequent in UC-associated than in sporadic invasive colon carcinomas, this being linked to elevated survivin expression. The control of apoptosis may be different in the 2 types of tumorigenesis.

Topics: Adenoma; Apoptosis; Carcinoma; Cell Division; Colitis, Ulcerative; Colonic Neoplasms; Cyclin D1; Humans; Immunohistochemistry; Inhibitor of Apoptosis Proteins; Microtubule-Associated Proteins; Neoplasm Proteins; Survivin

Conjugated linoleic acid (CLA) is a term used to describe the different conjugated isomers of linoleic acid. CLA has been found to be anticarcinogenic in mammary cancer, but its effects on colon carcinogenesis are still inconclusive. In this study, the isomer-specific effects of the cis-9, trans-11 and trans-10, cis-12 CLA isomers were investigated in the Min mouse model for intestinal carcinogenesis. The Min mice (n = 10/group) were fed either an AIN-93G control diet or a diet containing 1 g/100 g cis-9, trans-11 or trans-10, cis-12 CLA for 8 wk. The number and size of adenomas were measured and the proteins from the small intestinal tissues extracted for immunoblotting analysis. The number of adenomas did not differ, but the size of the adenomas was greater in the distal part of the small intestine in mice fed the trans-10, cis-12 isomer than in controls (1.19 +/- 0.16 vs. 0.94 +/- 0.21 mm, mean +/- SD, P < 0.01). The same isomer caused an increase in lipid peroxidation, measured as urinary 8-iso-prostaglandin (PG)F(2alpha). Nuclear p65 protein of the mucosal tissue was not detectable in the trans-10, cis-12 group, which differed (P < 0.05) from the control group. Cyclin D1, a target for the nuclear factor (NF)-kappaB pathway, was elevated in the trans-10, cis-12 group compared with the control group (P < 0.01), but cyclooxygenase-2 levels were not higher. There was no difference in beta-catenin protein levels between the groups. The results indicate that the trans-10, cis-12 isomer of CLA can act as a cancer promoter in colon carcinogenesis possibly through pathways affecting NF-kappaB and cyclin D1.

Topics: Adenoma; Animals; Cell Division; Cyclin D1; Diet; Intestinal Mucosa; Intestinal Neoplasms; Linoleic Acids; Mice; Mice, Inbred Strains; NF-kappa B; Stereoisomerism

An immunohistochemical method for assessing cell-cycle phase distribution in colorectal resection specimens would enable phase data to be incorporated into diagnostic algorithms for the estimation of prognosis and response to adjuvant chemotherapy in colorectal cancer. In contrast to flow cytometry, an immunohistochemical method would also allow the phase distribution to be examined within morphologically heterogeneous regions of neoplasms. Paraffin sections of normal colon (n = 25), colonic adenoma (n = 15), and colonic adenocarcinoma (n = 30) were analysed by immunohistochemistry using antibodies against markers of cell-cycle entry, Mcm-2 and Ki67, and putative markers of the cell-cycle phase, cyclins D1 and E (putative markers of G1 phase), cyclin A (S phase), cytoplasmic cyclin B1 (G2 phase), and phosphohistone H3 (M phase). The phase specificity of each marker was assessed by examining the degree of co-expression of adjacent phase markers using double-antibody fluorescence confocal microscopy and by comparison with flow cytometric analysis performed on adjacent tissue sections. The S-phase specificity of detectable cyclin A was also assessed in combination with in situ DNA replication using fluorescence confocal microscopy. All cells expressing phase markers co-expressed Mcm-2. Adjacent phase markers were not significantly co-expressed, confirming the relative specificity of these markers in tissue sections of colon. Cell-cycle phase distribution, calculated by immunohistochemistry, compared well with phase analyses obtained by flow cytometry. No cells expressed cyclin A in the absence of active DNA replication. The S-phase labelling index, as defined by detectable cyclin A expression, showed a positive correlation with the Mcm-2 labelling index and increased in the progression from normal colon to adenocarcinoma. In conclusion, a combination of these cell-cycle phase markers can be used to calculate the distribution of cells throughout each phase of the cell cycle in colorectal tissue sections. Detectable cyclin A can be used as a surrogate marker of S phase and may be of value in predicting prognosis and response to adjuvant therapy.

Topics: Adenocarcinoma; Adenoma; Biomarkers; Cell Cycle; Cell Cycle Proteins; Colonic Neoplasms; Cyclin A; Cyclin B; Cyclin B1; Cyclin D1; Cyclin E; Flow Cytometry; Histones; Humans; Immunohistochemistry; Ki-67 Antigen; Microscopy, Confocal; Minichromosome Maintenance Complex Component 2; Nuclear Proteins; Predictive Value of Tests; Prognosis; Sensitivity and Specificity; Statistics, Nonparametric

Cyclin D1, encoded by the CCND1 gene and activated by the adenomatous polyposis coli-beta-catenin-T-cell factor/lymphoid enhancing factor pathway, induces G(1) to S-phase cell cycle transition, promoting cell proliferation. A recently described codon 242, exon 4, G to A single nucleotide polymorphism (A870G) produces a longer half-life cyclin D1. To investigate whether CCND1 genotype influences risk for colorectal adenoma, we genotyped CCND1 by PCR/RFLP on 161 incident sporadic adenoma cases and 213 controls ages 30-74 years in a North Carolina colonoscopy-based case-control study. At least one polymorphic A allele was found in 68% of cases and 60% of controls. Having an A allele was associated with increased risk for adenoma: the age- and sex-adjusted odds ratio (OR) was 1.5 [95% confidence interval (CI) 1.0-2.4], a finding that was stronger for those whose adenomas were multiple (OR 2.9, 95% CI 1.4-6.0), larger (>or=1 cm; OR 2.4, 95% CI 1.2-4.8), had moderate to severe dysplasia (OR 2.1, 95% CI 1.1-3.8), or were in the right side of the colon (OR 3.6, 95% CI 1.3-10.0). Joint risk factor multivariate analyses revealed stronger positive associations among those who were older (>57 years; OR 2.8, 95% CI 1.4-5.5), male (OR 2.8, 95% CI 1.3-5.7), currently smoked (OR 2.7, 95% CI 1.3-5.7), or currently drank alcohol (OR 2.2, 95% CI 1.2-4.2) if they had an A allele and stronger inverse associations among those who used nonsteroidal anti-inflammatory drugs (OR 0.4, 95% CI 0.2-0.9) or had higher calcium intakes (OR 0.4, 95% CI 0.2-0.9) if they had no A allele. These data support the hypothesis that the CCND1 A870G polymorphism may increase risk for colorectal neoplasms.

Topics: Adenoma; Alleles; Cell Division; Colorectal Neoplasms; Cyclin D1; Epithelial Cells; Female; Genetic Predisposition to Disease; Humans; Intestinal Mucosa; Male; Middle Aged; Molecular Epidemiology; Polymorphism, Genetic

Cyclin D1 and E2F-1 proteins are essential for the regulation of the G1/S transition through the cell cycle. Cyclin D1, a product of the bcl-1 gene, phosphorylates the retinoblastoma protein, releasing E2F-1, which in turn activates genes involved in DNA synthesis. Expression patterns of E2F-1 protein in thyroid proliferations have not been reported. This study used monoclonal antibodies for cyclin D1 and E2F-1 proteins to immunostain sections of normal thyroid, hyperplastic (cellular) nodules, follicular adenomas, follicular carcinomas, and papillary carcinomas. The proliferation rate was examined using an antibody specific for the Ki-67 antigen. Fluorescence in situ hybridization (FISH) methods and chromosome 11-specific probes were also employed to determine chromosome copy number and to assess for evidence of amplification at the 11q13 locus in papillary and follicular carcinomas with cyclin D1 overexpression. Concurrent overexpression of Ki-67, cyclin D1, and E2F-1 was found in the majority of benign and malignant thyroid lesions, compared with normal thyroid tissue. Cyclin D1 up-regulation was not due to extra copies of chromosome 11, or bcl-1 gene amplification. Malignant tumours showed the highest expression for all three markers, particularly papillary carcinomas. E2F-1 was detected at the same or slightly lower levels than cyclin D1. It was only found when cyclin D1 was overexpressed. Because cyclin D1 normally activates E2F-1, up-regulation of cyclin D1 may lead to E2F-1 overexpression in benign and malignant thyroid lesions.

Topics: Adenocarcinoma, Follicular; Adenoma; Carcinoma, Papillary; Cell Cycle Proteins; Cell Division; Cyclin D1; DNA-Binding Proteins; E2F Transcription Factors; E2F1 Transcription Factor; Humans; Hyperplasia; In Situ Hybridization, Fluorescence; Ki-67 Antigen; Neoplasm Proteins; Thyroid Gland; Thyroid Neoplasms; Transcription Factors

Parathyroid adenomas are benign uniglandular tumors and are the most common cause of primary hyperparathyroidism. Several genetic changes in parathyroid tumors, including inactivation of tumor suppressor genes, activation of oncogenes and loss of heterozygosity at several chromosomal loci, have been reported. In this study, we analyzed the status of cyclin D1 and beta-catenin in 24 cases of parathyroid adenoma. Immunohistochemistry of cyclin D1 showed positive staining in 9 (37.5%) of the 24 parathyroid adenomas. The status of beta-catenin, which has recently been identified as a regulator of cyclin D1 transcription, was examined by direct sequencing of exon 3 of the beta-catenin gene and immunohistochemistry of beta-catenin protein, but neither mutation nor accumulation of beta-catenin was detected in any of the cases. These results indicate that cyclin D1 is frequently accumulated in parathyroid adenomas, independently of dysfunction in the Wnt signaling pathway.

Topics: Adenoma; beta Catenin; Cell Adhesion; Cyclin D1; Cytoskeletal Proteins; DNA Mutational Analysis; Exons; Humans; Immunohistochemistry; Mutation; Parathyroid Neoplasms; Signal Transduction; Trans-Activators; Transcription, Genetic

Alterations of the Wnt/beta-catenin signaling pathway are known to occur in mutations of the component genes such as APC, Axin, and beta-catenin, and play a pathogenetic role in tumorigenesis. Activated Wnt signaling stabilizes beta-catenin, which associates with T cell factor, resulting in transactivation of the downstream target genes including c-myc and cyclin D1. To investigate the involvement of Wnt/beta-catenin signaling pathway in thyroid tumorigenesis, we analyzed its activation and localization in 5 human thyroid cancer cell lines and 132 thyroid tumor tissue samples. Dislocalization of beta-catenin was observed in all cell lines. Constitutive activation of T cell factor in two of four thyroid cancer cell lines was observed using reporter gene assay. Furthermore, high expression levels of c-Myc and cyclin D1 were observed in cell lines that showed cytoplasmic or nuclear accumulation of beta-catenin. In 132 paraffin-embedded thyroid carcinoma tissue samples, cytoplasmic beta-catenin was immunohistochemically observed in 52 out of 78 (67%) papillary thyroid cancers, but only in 3 of 34 (9%) follicular adenomas and 5 of 20 (25%) follicular cancers. Cytoplasmic localization of beta-catenin significantly correlated with overexpression of cyclin D1 in papillary carcinomas. Our results suggest that aberrant activation of Wnt/beta-catenin signaling is strongly involved in thyroid tumorigenesis.

Topics: Adenocarcinoma, Follicular; Adenoma; Adenomatous Polyposis Coli Protein; Axin Protein; beta Catenin; Carcinoma, Papillary; Cells, Cultured; Cyclin D1; Cytoskeletal Proteins; DNA Mutational Analysis; Gene Expression; Humans; Immunohistochemistry; Proteins; Repressor Proteins; TCF Transcription Factors; Thyroid Neoplasms; Tissue Distribution; Trans-Activators; Transcription Factor 7-Like 2 Protein; Transcription Factors; Transcriptional Activation

The roles of the MYC, ERBB2, and CCND1 genes in thyroid carcinogenesis are poorly known. We used real-time quantitative polymerase chain reaction (PCR) assays based on fluorescent TaqMan methodology to quantify MYC, ERBB2, and CCND1 gene amplification and expression in 24 benign tumors (adenomas and goiter nodules) and 12 carcinomas (9 papillary, 2 follicular, and 1 anaplastic) of the thyroid. Real-time PCR is a recently developed method for nucleic acid quantification in homogeneous solutions, and has the potential to become a reference in terms of performance, accuracy, sensitivity, wide dynamic range, excellent interlaboratory agreement, and high throughput capacity, while avoiding the need for tedious post-PCR processing. Overexpression (>5 standard deviations above mean for normal thyroid tissues) of the ERBB2 and CCND1 genes was observed (3.2- to 5.2-fold and 3.8- to 8.4-fold, respectively) in 5 (14%) and 13 (36%) of 36 neoplastic thyroid RNA samples, respectively. Overexpression of the CCND1 gene was observed in both the benign and malignant thyroid tumors, whereas the ERBB2 gene was mainly overexpressed in malignant thyroid tumors. None of the neoplastic thyroid samples overexpressed MYC. No MYC, ERBB2, or CCND1 gene amplification was identified. These results suggest that the CCND1 gene plays an early role and the ERBB2 gene a later role in thyroid tumorigenesis.

Topics: Adenoma; Adult; Carcinoma; Carcinoma, Papillary; Carcinoma, Papillary, Follicular; Cyclin D1; Gene Dosage; Genes, erbB-2; Genes, myc; Goiter, Nodular; Humans; Middle Aged; Reference Values; Reverse Transcriptase Polymerase Chain Reaction; RNA, Messenger; Thyroid Gland; Thyroid Neoplasms

Hyperparathyroidism may result from parathyroid hyperplasia or adenoma, or rarely from parathyroid carcinoma. Pericentromeric inversion of chromosome 11 that results in activation of the P:RAD1/cyclin D1 gene and tumor suppressor gene loss have been described as genetic abnormalities in the evolution of parathyroid neoplasms. We studied tissue samples taken from primary parathyroid hyperplasia, parathyroid adenoma, and histologically normal parathyroid tissue by comparative genomic hybridization, fluorescent in situ hybridization, and immunohistochemistry for cyclin D1. DNA copy number changes were infrequent in primary hyperplasia (4 of 24, 17%), but common in adenomas (10 of 16, 63%; P: = 0.0059). The most common change was deletion of the entire chromosome 11 or a part of it, with a minimal common region at 11q23. This change was present in five (31%) adenomas and two (8%) primary hyperplasias. Fluorescent in situ hybridization confirmed the presence of both MEN1 alleles located at 11q13 despite deletion of 11q23 in all three cases studied. Cyclin D1 was overexpressed in six (40%) of the 15 adenomas studied, whereas none of the 27 hyperplasias (P: = 0.0010) nor the five histologically normal tissue samples overexpressed cyclin D1. Either DNA copy number loss or cyclin D1 overexpression was present in 13 (81%) of the 16 adenomas. We conclude that DNA copy number loss and cyclin D1 overexpression are common in parathyroid adenomas. The region 11q23 is frequently lost in parathyroid adenomas and occasionally in parathyroid hyperplasias, and this suggests the possibility that a tumor suppressor gene that is important in their pathogenesis is present on 11q23.

Topics: Adenoma; Adult; Aged; Chromosomes, Human, Pair 11; Cyclin D1; Female; Gene Deletion; Gene Dosage; Humans; In Situ Hybridization, Fluorescence; Male; Middle Aged; Nucleic Acid Hybridization; Parathyroid Neoplasms

The relationship between abnormal cell proliferation and aberrant control of hormonal secretion is a fundamental and poorly understood issue in endocrine cell neoplasia. Transgenic mice with parathyroid-targeted overexpression of the cyclin D1 oncogene, modeling a gene rearrangement found in human tumors, were created to determine whether a primary defect in this cell-cycle regulator can cause an abnormal relationship between serum calcium and parathyroid hormone response, as is typical of human primary hyperparathyroidism. We also sought to develop an animal model of hyperparathyroidism and to examine directly cyclin D1's role in parathyroid tumorigenesis. Parathyroid hormone gene regulatory region--cyclin D1 (PTH--cyclin D1) mice not only developed abnormal parathyroid cell proliferation, but also developed chronic biochemical hyperparathyroidism with characteristic abnormalities in bone and, notably, a shift in the relationship between serum calcium and PTH. Thus, this animal model of human primary hyperparathyroidism provides direct experimental evidence that overexpression of the cyclin D1 oncogene can drive excessive parathyroid cell proliferation and that this proliferative defect need not occur solely as a downstream consequence of a defect in parathyroid hormone secretory control by serum calcium, as had been hypothesized. Instead, primary deregulation of cell-growth pathways can cause both the hypercellularity and abnormal control of hormonal secretion that are almost inevitably linked together in this common disorder.

Topics: Adenoma; Animals; Bone and Bones; Calcium; Calcium-Binding Proteins; Chromosome Aberrations; Chromosome Disorders; Cyclin D1; Gene Rearrangement; Humans; Hyperparathyroidism; Mice; Mice, Transgenic; Parathyroid Hormone; Parathyroid Neoplasms

This study aimed at clarifying the factors closely related to the tumor progression of thyroid neoplasms. We examined the immunoreactivity of cyclin D1, p53, and p21waf1/cip1 proteins in 179 thyroid tumors originating from the follicular epithelium using an immunohistochemical technique. Cyclin D1 positivity was frequent in well-differentiated thyroid carcinomas (39/122 cases), but it was rarely seen in follicular adenomas (1/33 cases), (p < 0.05). Positivity for p53 was more frequent in poorly differentiated carcinomas (7/19 cases) and undifferentiated carcinomas (4/5 cases) than in well-differentiated carcinomas (14/122 cases) (p < 0,05, respectively). P21waf1/cip1 positivity was more frequent in well-differentiated thyroid carcinomas (43/122 cases) than in follicular adenomas (4/33 cases) (p < 0.05). Regarding the relationships of these proteins, co-positivity for cyclin D1 and p53 was observed more often in poorly differentiated carcinomas (5/7 cases) than in well-differentiated carcinomas (7/39 cases) (p < 0.05). Most cases with cyclin D1 positivity did not show p21waf1/cip1 expression in poorly differentiated carcinomas (6/7 cases). Three cases examined showed co-positivity of p53 and p21waf1/cip1. Our results suggest that cyclin D1 is invoved in thyroid oncogenesis. Moreover, p53 might be closely related to the development of poorly differentiated carcinomas and undifferentiated carcinomas originating from well-differentiated carcinomas.

Topics: Adenoma; Adolescent; Adult; Aged; Aged, 80 and over; Carcinoma; Child; Cyclin D1; Cyclin-Dependent Kinase Inhibitor p21; Cyclins; Female; Humans; Immunoenzyme Techniques; Male; Middle Aged; Thyroid Neoplasms; Tumor Suppressor Protein p53

The G1/S-phase controlling mechanism known as the RB pathway is commonly deregulated in human malignancies. Here, the abundance and localization of key components of the retinoblastoma (RB) pathway were determined in exophytic and flat colorectal adenomas.. Samples of normal colonic mucosa (n = 41) and flat (n = 45) and exophytic (n = 26) adenomas were examined immunohistochemically using antibodies to cyclins D1, D2, D3, cyclin-dependent kinase (CDK) 4, retinoblastoma protein (pRB), and the CDK inhibitors p16INK4a, p18INK4c, and p19INK4d.. In normal colonic epithelium, cyclin D2 was undetectable; expression of cyclin D1, CDK4, and pRB correlated with proliferation; and p16, p18, p19, and cyclin D3 were most abundant in quiescent, differentiated cells. Adenomas showed elevated expression of cyclin D1 and pRB, frequent induction of cyclin D2, and absence of p16. No obvious abnormalities were found for p18, p19, or cyclin D3. Overexpressed cyclin D2 was more common among exophytic and pRB among flat adenomas, respectively. Elevated cyclin D1, D2, and CDK4 correlated with enhanced dysplasia.. Aberrant expression of cyclins D1, D2, CDK4, p16, and pRB occur in significant subsets of exophytic and flat adenomas, particularly among cases with high-grade dysplasia. Such defects of the RB pathway may perturb cell-cycle control and thereby contribute an early step in colorectal tumorigenesis.

Topics: Adenoma; Adult; Aged; Aged, 80 and over; Colonic Neoplasms; Cyclin D1; Cyclin D2; Cyclin D3; Cyclin-Dependent Kinase 4; Cyclin-Dependent Kinase Inhibitor p16; Cyclin-Dependent Kinases; Cyclins; Female; G1 Phase; Humans; Male; Middle Aged; Proto-Oncogene Proteins; Retinoblastoma Protein

Components of the pRb/p16/cyclin D1/CDK4 pathway are frequent targets in numerous tumour types, including those of pituitary origin. However, previous studies of pituitary tumours have examined individual components of this pathway. Therefore, to determine their overall contribution we have simultaneously examined the immunohistochemical status of pRb, p16 and cyclin D1 and analysed the CDK4 gene for a characterized activating mutation. Of the total pituitary tumour cohort (29 clinically non-functioning adenomas and 16 somatotrophinomas) abnormal expression of either pRb, p16 or cyclin D1 was observed in 36 of 45 (80%) tumours and was significantly (P = 0.005) associated with non-functioning tumours (27/29; 93%) compared with somatotrophinomas (9/16, 56%). Loss of either pRb or p16 expression was mutually exclusive in 23 of 45 (51%) tumours, whilst concomitant loss of pRb and p16 expression was observed in five tumours. Cyclin D1 overexpression was observed in 22 of 45 (49%) tumours, however, there was no significant association between overexpression of cyclin D1 and the expression status of either pRb or p16. In addition, no activating mutations within codon 24 of the CDK4 gene were detected. This study provides evidence for the first time that components of the pRb/p16/cyclin D1/CDK4 pathway, either alone or in combination, are frequently deregulated in human pituitary tumours, suggesting that this pathway may be a useful target in drug or gene therapeutic approaches.

Topics: Adenoma; Codon; Cyclin D1; Cyclin-Dependent Kinase 4; Cyclin-Dependent Kinase Inhibitor p16; Cyclin-Dependent Kinases; DNA Primers; G1 Phase; Humans; Immunohistochemistry; Mutation; Pituitary Neoplasms; Proto-Oncogene Proteins; Retinoblastoma Protein; S Phase

The oncogenes cyclin D1 and D3 are overexpressed in many tumors. Topoisomerase II alpha is found in proliferating cells. The immunohistological expression of cyclin D1, cyclin D3, and Topoisomerase II alpha was studied in a collection of 60 clinically inactive surgically removed pituitary adenomas of the follicle-stimulating hormone/luteinizing hormone (FSH/LH) cell complex (20 null cell adenomas, 20 oncocytomas, and 20 FSH/LH cell adenomas) for correlation with other proliferation markers (Ki-67, PCNA) and with clinical data. Whereas cyclin D1 was positive only in one invasive null cell adenoma (1.7%) with some p53-positive nuclei, cyclin D3 was overexpressed in the nuclei of 41 tumors (68%). Topoisomerase II alpha was demonstrated in the nuclei of 42 adenomas (70%) with no significant differences discernible between the three adenoma subtypes. There was no significant correlation to the time of development of tumor symptoms, but a correlation of Topoisomerase II alpha with cyclin D3 and the proliferation marker Ki-67 (Mib1). From these data we conclude that cyclin D3 and Topoisomerase II alpha appear to be additional markers for proliferation which can be used for prognosis index in surgical pathology of the pituitary.

Topics: Adenoma; Adolescent; Adult; Aged; Aged, 80 and over; Antigens, Neoplasm; Biomarkers, Tumor; Cyclin D1; Cyclin D3; Cyclins; DNA Topoisomerases, Type II; DNA-Binding Proteins; Humans; Immunohistochemistry; Ki-67 Antigen; Middle Aged; Pituitary Neoplasms; Proliferating Cell Nuclear Antigen; Tumor Suppressor Protein p53

Activation of beta-catenin/T cell factor (TCF) transcription as a result of mutations in the adenomatous polyposis coli (APC) and/or beta-catenin genes occurs in the majority of colon tumors. An increasing number of genes, including c-myc and cyclin D1, have been implicated as targets of this pathway. We now report that the dominant negative helix-loop-helix regulator Id2 is also a target of the beta-catenin/TCF transcription pathway in colon adenocarcinoma. Investigation of the mechanism for the overexpression of Id2 in colon carcinoma cells demonstrated that the Id2 promoter is activated, and the Id2 protein is up-regulated by beta-catenin. Conversely, reducing free beta-catenin blocked this induction of promoter activity. We have also used an electrophoretic mobility shift assay and supershift to identify a motif in the Id2 promoter that binds to TCF4 protein. Site-directed mutagenesis of this motif abolished promoter reporter activity. Both transfection of Id2 into SW480 cells and induction of Id2 in HT29 colon cells was found to increase anchorage-independent survival of these cells. Growing evidence associates disruption to Id2 expression with tumorigenesis, and our findings suggest that this dysregulation of Id2 expression is due to the activation of the beta-catenin/TCF pathway.

Topics: Adenocarcinoma; Adenoma; Amino Acid Motifs; beta Catenin; Cell Differentiation; Cell Division; Cell Line; Cell Survival; Colonic Neoplasms; Cyclin D1; Cytoskeletal Proteins; DNA-Binding Proteins; Genes, Dominant; Humans; Immunoblotting; Immunohistochemistry; In Situ Hybridization; Inhibitor of Differentiation Protein 2; Mutagenesis, Site-Directed; Mutation; Plasmids; Promoter Regions, Genetic; Protein Binding; Repressor Proteins; Trans-Activators; Transcription Factors; Transcription, Genetic; Transcriptional Activation; Transfection; Tumor Cells, Cultured; Up-Regulation

The cyclin D1 (CCND1) gene contains a frequent A/G polymorphism within the splice donor region of exon 4/intron 4. CCND1 genotype is associated with clinical outcome in a number of malignancies although prognostic significance varies with tumour type. We examined CCND1 allele frequencies and genotype distribution in 294 patients with sporadic pituitary adenomas of various histologies. CCND1 allele frequencies and distribution of genotypes were similar in the 294 cases compared with previously reported control populations. Analysis according to tumour subtype showed no statistical difference in allele frequencies compared with controls. However, CCND1 genotype distribution in the somatotrophinomas showed a significant difference compared with normal controls (P = 0.008). We next examined CCND1 allele frequencies and genotype distribution across the tumour grades. Within the total tumour cohort the CCND1 allele frequencies showed a significant inverse relationship across the tumour grades (P = 0.005). The CCND1 A allele progressively increased from grade 1 (0.37) through to grade 4 (0.62) tumours, whilst the CCND1 G allele frequency progressively decreased from grade 1 (0.63) through to grade 4 (0.38) tumours. Trend analysis of CCND1 genotypes showed a significant progressive increase in AA frequency from grade 1 (15%) through to grade 4 (46%) tumours (P = 0.005). The CCND1 GG genotype progressively decreased from grade 1 (41%) through to grade 4 (23%) tumours (P = 0.204). No statistical significance was observed between CCND1 AG genotype and tumour grades. While the functional significance of the observed segregation of the CCND1 A/G polymorphism and tumour grade is unclear, our data suggest that CCND1 allele frequencies and genotype distributions show significant differences between tumour grades in sporadic pituitary adenomas. Since CCND1 genotype may be determined by analysis of peripheral blood samples it may provide a useful predictive marker for those tumours likely to show invasive behaviour. This may be clinically useful in indicating which tumours should receive adjunctive treatment (e.g. radiotherapy) immediately after surgical resection.

Topics: Adenoma; Adrenocorticotropic Hormone; Codon; Cohort Studies; Cyclin D1; DNA Primers; Exons; Genotype; Growth Hormone; Humans; Introns; Neoplasm Staging; Pituitary Neoplasms; Polymerase Chain Reaction; Polymorphism, Genetic; Prolactinoma; Recurrence; Retrospective Studies; Sequence Analysis, DNA

Deregulation of G1 cyclins has been reported in several human and rodent tumors including colon cancer. To investigate the expression pattern of G1 cyclins in 1,2- dimethyl-hydrazine dihydrochloride (DMH)-induced rat colon carcinogenesis, we studied the expression of cyclin D1 and cyclin E by quantitative reverse transcription-polymerase chain reaction (RT-PCR) analysis and immunohistochemistry (IHC). The mRNA level of cyclin D1 was increased 1.2-fold in adenocarcinomas but not significantly in adenomas, when compared with normal rat colonic mucosa (p<0.05). The cyclin E mRNA level was increased 2.7-fold in adenomas and 3.3-fold in adenocarcinomas (p<0.05). The PCNA mRNA level was also increased 1.9-fold in adenomas and 1.8-fold in adenocarcinomas (p<0.05). Immunohistochemical staining revealed exclusive nuclear staining of the neoplastic cells for cyclin D1, cyclin E and PCNA. Cyclin D1 expression was detected in 56.3% of the adenomas and in 61.5% of the adenocarcinomas examined, whereas cyclin E expression was detected in 87.5% of the adenomas and in 92.3% of the adenocarcinomas. Overall, cyclin D1, cyclin E and PCNA expression was significantly increased at both the mRNA and protein levels in normal colonic mucosa, adenomas and adenocarcinomas, but there was no significant difference in the degree of expression of these genes in adenomas and adenocarcinomas. Our results indicate that the overexpression of cyclin D1 and cyclin E may play an important role during the multistage process of rat colon carcinogenesis, at a relatively early stage, and may disturb cell-cycle control in benign adenomas, and thereafter, participate in tumor progression.

Topics: 1,2-Dimethylhydrazine; Adenocarcinoma; Adenoma; Animals; Carcinogens; Cell Cycle; Colon; Colonic Neoplasms; Cyclin D1; Cyclin E; Gene Expression Regulation, Neoplastic; Immunohistochemistry; Male; Proliferating Cell Nuclear Antigen; Rats; Rats, Sprague-Dawley; Reverse Transcriptase Polymerase Chain Reaction; RNA, Messenger

Cyclin D1 overexpression is remarkably frequent in several human carcinomas and is believed to be a critical event in oncogenesis. We examined cyclin D1 expression, p53 expression, and the Ki-67 labeling index by immunostaining in human gallbladder mucosa in conditions varying from normal to malignant tissue. We also examined K-ras codon 12 mutations in these tissues with a two-step polymerase chain reaction. Nuclear cyclin D1 overexpression was observed in 48% of carcinomas occurring independently of adenoma, but not in adenomas, carcinomas arising in adenomas, or nonneoplastic lesions. Cytoplasmic cyclin D1 overexpression was observed in about 15% of abnormal specimens, irrespective of the type of epithelial abnormality. Carcinomas showing nuclear cyclin D1 overexpression had significantly higher Ki-67 labeling indexes than those with no overexpression. Moderately to poorly differentiated adenocarcinomas showed a higher incidence of nuclear cyclin D1 overexpression than papillary to well differentiated carcinomas. Specimens with cyclin D1 overexpression showed a high incidence of lymph permeation, venous permeation, and lymph node metastasis. We conclude that nuclear cyclin D1 overexpression is a critical event importantly associated with cell proliferation and invasive growth in gallbladder carcinogenesis, and that cyclin D1 immunostaining may become a useful marker for evaluating gallbladder carcinomas.

Topics: Adenocarcinoma; Adenoma; Biomarkers, Tumor; Cell Division; Cell Nucleus; Codon; Cyclin D1; DNA, Neoplasm; Gallbladder Neoplasms; Genes, ras; Humans; Immunoenzyme Techniques; Ki-67 Antigen; Point Mutation; Polymerase Chain Reaction; Retrospective Studies; Tumor Suppressor Protein p53

We have reported protective effects of dietary administration of a powder "CHRP" containing high amounts of beta-cryptoxanthin and hesperidin prepared from a Satsuma mandarin (Citrus unshiu Marc.) juice on azoxymethane (AOM)-induced rat aberrant crypt foci through suppression of crypt cell proliferation and/or induction of detoxifying enzymes. In the present study, we investigated the modifying effects of a commercial Satsuma mandarin (Citrus unshiu Marc.) juice (MJ) and those of MJ2 and MJ5, which were prepared from MJ and are richer in beta-cryptoxanthin and hesperidin than MJ, on the occurrence of colonic tumors induced by AOM in male F344 rats. Rats were given 2 weekly s.c. injections of AOM (20 mg/kg body weight) to induce colonic neoplasms. They also received MJ, MJ2, or MJ5 as a drinking water at night for 36 weeks, starting 1 week after the last dosing of AOM. AOM exposure produced colonic adenocarcinoma with an incidence of 69% and a multiplicity of 0.76 +/- 0.57/rat at week 38. MJ, MJ2, and MJ5 administration significantly reduced the frequency of colonic carcinoma [MJ: 35% (49% reduction), p < 0.02; MJ2: 20% (64% reduction), p = 0.0028; and MJ5: 15% (78% reduction), p < 0.00021] and multiplicity [MJ: 0.40 +/- 0.58 (47% reduction), p < 0.05; MJ2: 0.25 +/- 0.43 (67% reduction), p < 0.005; and MJ5: 0.15 +/- 0.36 (80% reduction), p < 0.001]. Also, the numbers of cancer cells positive for proliferative cell nuclear antigen (PCNA) and cyclin D1 in colonic tumors were lowered by these treatments. In addition, treatment with MJ, MJ2, or MJ5 significantly increased apoptotic index in colonic adenocarcinoma. These findings might suggest effective chemopreventive ability of MJs, especially MJ5, in colon tumorigenesis.

Topics: Adenocarcinoma; Adenoma; Animals; Anticarcinogenic Agents; Apoptosis; Azoxymethane; beta Carotene; Beverages; Carcinogens; Citrus; Colonic Neoplasms; Cryptoxanthins; Cyclin D1; Hesperidin; Male; Proliferating Cell Nuclear Antigen; Rats; Rats, Inbred F344; Xanthophylls

This study was conducted to determine whether comparative genomic hybridization (CGH) is a more sensitive method for detecting genetic aberrations than other tests currently in use.. The authors used CGH to examine 40 primary and 13 recurrent adenomas obtained from 52 patients for loss and gain of genetic material. Copy number aberrations (CNAs) were detected in 25 (48%) of the 52 patients studied. The chromosomes affected were, in order of decreasing frequency, 11, 7, X, 1, 8, 13, 5, 14, 2, 6, 9, 10, 12, 3, 18, 21, 4, 16, 15, 19, 22, and Y. Endocrinologically active adenomas were more likely to contain (p = 0.009) and had a greater number (p = 0.003) of CNAs. Of 26 adenomas with CNAs, 18 showed multiple aberrations involving entire chromosomes or chromosome arms. The most frequent CNA involving a chromosome subregion, which was present in four (8%) of 53 adenomas, was the loss of all chromosome 11 material except for a preserved common segment containing 11q13. Immunoperoxidase staining did not detect cyclin D1 expression in those four cases, making cyclin D1 an unlikely target of this rearrangement.. These findings indicate that genetic abnormalities are present in pituitary adenomas at a higher rate than previously reported, are associated with endocrinological activity, and often involve several chromosomes. Rearrangement at 11q13 may inactivate a tumor suppressor gene or activate an oncogene that is important in the initiation or progression of sporadic pituitary adenomas.

Topics: Adenoma; Adolescent; Adult; Aged; Chromosome Aberrations; Chromosomes, Human, Pair 11; Cyclin D1; Female; Gene Rearrangement; Humans; Immunoenzyme Techniques; Male; Middle Aged; Nucleic Acid Hybridization; Pituitary Neoplasms; Sensitivity and Specificity

In primary hyperparathyroidism, certain genetic abnormalities responsible for parathyroid tumorigenesis are proposed, and it has been reported that the overexpression of PRAD1/cyclin D1 induced by a DNA rearrangement of the parathyroid hormone (PTH) gene is one of the genetic disorders in a number of primary parathyroid adenomas. However, in secondary hyperparathyroidism caused by uremia, the mechanism of monoclonal proliferation in nodular parathyroid hyperplasia is not well understood. To elucidate the mechanism, we examined the expression of PRAD1/cyclin D1, retinoblastoma gene products, and Ki67 in primary adenoma and secondary hyperplasia.. In adenomas (N = 15) and associated glands (N = 7) with normal histology obtained from patients with primary hyperparathyroidism and in diffuse (N = 14), multinodular (N = 58), and single nodular (N = 28) glands from patients who underwent parathyroidectomy for renal hyperparathyroidism, the expression of these cell cycle regulators was evaluated by immunohistochemical technique. A labeling index was used to define the proportion of cells with positive nuclear staining by each antibody.. In 6 out of 15 (40%) primary adenomas, PRAD1/cyclin D1 was overexpressed (a labeling index of more than 500), possibly because of the PTH gene rearrangement, but not in secondary hyperplasia, including single nodular glands. Compared with diffuse hyperplasia, nodular hyperplasia showed a significantly higher expression of PRAD1/cyclin D1 (P < 0.05), retinoblastoma gene products (P < 0.05), and Ki67 (P < 0.05). However, no statistically significant correlation between the expression of PRAD1/cyclin D1 and that of Ki67 was observed in both primary adenoma and secondary hyperplasia.. These results suggest that in secondary hyperplasia caused by uremia, at least remarkable overexpression of PRAD1/cyclin D1 induced by PTH gene rearrangement may be not the major genetic abnormality responsible for tumorigenesis. Heterogenous genetic changes seem to contribute to monoclonal proliferation of parathyroid cells induced by the expression of PRAD1/cyclin D1 or by some other mechanism independent of the amplification of the proto-oncogene.

Topics: Adenoma; Biomarkers, Tumor; Cell Nucleus; Cyclin D1; Humans; Hyperplasia; Immunohistochemistry; Ki-67 Antigen; Kidney Failure, Chronic; Middle Aged; Parathyroid Glands; Parathyroid Neoplasms; Proto-Oncogene Mas; Retinoblastoma Protein

A general increase in protein synthesis and a specific increase in the synthesis of growth-promoting proteins are necessary for mitogenesis. Regulation of protein synthesis, as well as preferential translation of some mRNAs coding for growth promoting proteins (e.g. cyclin D1), involves the essential protein synthesis initiation factor eIF-4E. This factor is induced by various oncoproteins, and, when overexpressed, it can transform cultured cells. In this report we explore the roles of eIF-4E in human neoplastic disorders of the colon and in the regulation of general and specific protein synthesis. We find that eIF-4E is increased in colon adenomas and carcinomas, and this increase is accompanied in most but not all cases by elevation of cyclin D1 levels. While general protein synthesis is increased by eIF-4E overexpression in cultured cells, only a small proportion of proteins is preferentially upregulated by eIF-4E, as revealed by two-dimensional gel electrophoresis. These results are consistent with the view that eIF-4E plays a role in carcinogenesis by increasing general protein synthesis and by preferentially upregulating a subset of putative growth promoting proteins. Our results, taken together with the recent findings that c-myc transcription is negatively regulated by APC and our earlier data on transcriptional activation of eIF-4E expression by c-Myc suggest that eIF-4E is a downstream target of the APC/beta-catenin/Tcf-4 pathway, and is strongly involved in colon tumorigenesis.

Topics: 3T3 Cells; Adenocarcinoma; Adenoma; Animals; Blotting, Western; Cell Transformation, Neoplastic; Colonic Neoplasms; Cyclin D1; Eukaryotic Initiation Factor-4E; Humans; Immunohistochemistry; Mice; Peptide Initiation Factors; Protein Biosynthesis; Tumor Cells, Cultured; Up-Regulation

In this study, we assessed the frequency of cyclin D1 protein expression in normal and neoplastic parathyroid tissue (10 parathyroid carcinomas, 28 adenomas, 18 hyperplasias, and 32 normal parathyroid glands) with use of a monoclonal anticyclin D1 antibody and a heat-induced epitope retrieval method. Overexpression of cyclin D1 was identified in 10 (91%) of 11 biopsy specimens from 10 patients with parathyroid carcinomas and in 11 (39%) of 28 parathyroid adenomas. In addition, 11 (61%) of 18 cases of parathyroid hyperplasia also expressed cyclin D1 protein, an observation not reported previously. These results confirm the high frequency of cyclin D1 expression in parathyroid carcinomas and adenomas. In addition, the results of this study indicate that overexpression of cyclin D1 protein is not limited to neoplastic proliferations of parathyroid tissue but is also seen in non-neoplastic proliferations of parathyroid gland. Cyclin D1 protein expression was rarely (<6%) present in normal parathyroid tissue.

Topics: Adenoma; Adult; Aged; Aged, 80 and over; Biopsy; Cyclin D1; Female; Humans; Hyperplasia; Immunohistochemistry; Male; Middle Aged; Parathyroid Glands; Parathyroid Neoplasms

Cyclin D1 plays an important role in the regulation of cell progression through G1 of the cell cycle and has been demonstrated to have oncogenic properties. Using RFLP-PCR, an A/G polymorphism within the cyclin D1 (CCND1) gene was analyzed in 151 sporadic human pituitary tumors, of which 60 were informative at this locus. Further analysis showed that in 15 of 60 (25%) tumors, there was evidence of allelic imbalance, which is indicative of gene amplification. Allelic imbalance was observed more frequently in invasive tumors (11 of 29 tumors; 38%) than in their noninvasive counterparts (4 of 31 tumors; 13%; P = 0.02). Forty-six of the tumors informative for the polymorphism were available for immunohistochemical analysis. Cyclin D1 expression (nuclear and/or cytoplasmic) was detected in 25 of 46 (54%) tumors. Of these cases, expression of nuclear cyclin D1 was detected in 9 of 46 (20%) tumors, whereas 16 of 46 (35%) tumors showed cyclin D1 staining exclusively confined to the cytoplasm. Neither nuclear staining nor cytoplasmic staining was observed in any of the normal pituitaries or in the negative control. Expression of cyclin D1 was observed in significantly more nonfunctional tumors (18 of 27 tumors; 67%) than in somatotrophinomas (7 of 19 tumors; 37%; P = 0.046). Nuclear cyclin D1 expression was observed more frequently in nonfunctional tumors (8 of 27 tumors; 30%) than in somatotrophinomas (1 of 19 tumors; 5%; P = 0.04). There was no correlation between cyclin D1 expression and tumor grade or between allelic imbalance of CCND1 and cyclin D1 expression. We conclude that amplification of CCND1 occurs in pituitary tumors and that the overexpression of cyclin D1 may be an early event in tumorigenesis. Cyclin D1 overexpression occurring in the absence of CCND1 allelic imbalance suggests that additional mechanisms responsible for deregulated cyclin D1 expression are involved in human pituitary tumorigenesis.

Topics: Adenoma; Alleles; Cell Cycle; Cyclin D1; Gene Amplification; Growth Hormone; Humans; Immunohistochemistry; Leukocytes; Pituitary Neoplasms; Polymerase Chain Reaction; Polymorphism, Genetic; Polymorphism, Restriction Fragment Length; Subcellular Fractions

We describe and discuss a method of protein extraction for Western blot analysis from formalin-fixed, paraffin-embedded tissue sections. From 5-mm2 50-micron-thick tissue sections, an abundance of proteins could be extracted by incubating the sections in lysis buffer containing 2% sodium dodecyl sulfate (SDS) at 100C for 20 min followed by incubation at 60C for 2 hr. Extracts yielded discernible protein bands ranging from 10 kD to 120 kD as identified by SDS-polyacrylamide gel electrophoresis (PAGE). Western blot analysis successfully detected membrane-bound protein such as E-cadherin, cytosolic protein such as beta-catenin, and nuclear proteins including proliferating cell nuclear antigen (PCNA), mutant-type p53, cyclin D1, cyclin E, and cyclin-dependent kinases (CDKs). With this technique, we could examine cyclin D1 and CDK2 expression in small adenomas compared with cancer tissues and normal mucosa. The simple method of protein extraction described here should make it possible to use large-scale archives of formalin-fixed, paraffin-embedded samples for Western blot analysis, and its application could lead to detailed analysis of protein expression. This new technique should yield valuable information for molecular biology.

Topics: Adenoma; Blotting, Western; CDC2-CDC28 Kinases; Colorectal Neoplasms; Cyclin D1; Cyclin-Dependent Kinase 2; Cyclin-Dependent Kinases; Formaldehyde; Humans; Nuclear Proteins; Paraffin; Proliferating Cell Nuclear Antigen; Protein Serine-Threonine Kinases; Proteins; Tissue Fixation

To clarify the events leading to the disruption of cell growth control that occurs during the development of pulmonary adenocarcinoma (AC), we used immunohistochemistry to evaluate the expression of G1 cycle regulators, cyclin D1, Rb protein (pRb), and p16 MTS1 protein and the tumour proliferation marker, Ki 67, both in AC of the lung and in its precursor lesion, atypical adenomatous hyperplasia (AAH). The frequency of lesions with cyclin D1 overexpression was relatively high in AAH (47-89%), but was decreased in early AC (28%) and overt AC (35%). The loss of pRb expression was rare in both AAH (0-18%) and early AC (0%), and was infrequent even in overt AC (13%). The loss of p16 expression was also relatively infrequent in both the premalignant and the malignant lesions (11-25%). Our results suggest that overexpression of cyclin D1 is an early event and plays an important part in tumorigenesis in the case of lung AC. However, cyclin D1 overexpression is not required for the development and maintenance of a malignant phenotype. It is likely that some cyclin D1-independent pathways other than Rb and p16 abnormalities have an important role in the malignant transformation from AAH to early AC.

Topics: Adenocarcinoma; Adenoma; Adult; Aged; Aged, 80 and over; Cyclin D1; Cyclin-Dependent Kinase Inhibitor p16; Female; Humans; Hyperplasia; Immunohistochemistry; Ki-67 Antigen; Lung; Lung Neoplasms; Male; Middle Aged; Retinoblastoma Protein

The cell cycle is controlled in part by cyclin-dependent kinases (CDKs), which are activated by forming complexes with cyclins. CDKs phosphorylate certain substrates to facilitate the proliferating cells through the cell cycle. CDK inhibitors (CDKIs) such as p27 inhibit cyclin-CDK complexes and function as a negative cell cycle regulator. The overexpression of the positive regulators (cyclins) or the underexpression of the negative regulators including p27 has been seen in a variety of neoplasms, but their role and interaction in thyroid carcinogenesis is yet to be established. We studied the expression of cyclins D1 and E, and the CDKI, p27 by immunohistochemistry in 116 cases, including 59 cases of follicular variant of papillary carcinoma (FVPC) and 57 cases of follicular adenoma (FA). The positive staining was divided into four grades: 1+ if less than 10%, 2+ if 11% to 25%, 3+ if 26% to 50%, and 4+ if greater than 50% of the nuclei of tumor cells stained positively. Cyclin D1 expression was seen in 37 (63%) FVPC and 34 (60%) FA. Cyclin E-positive cells were seen in 51 (86%) FVPC and 47 (82%) FA. No significant differences in the grade of cyclins D1 (P = .261) and E (P = .284) staining was seen between FVPC and FA. Of the 59 FVPC, 53 (89%) showed p27-positive cells; of these, 33 were 1+, nine were 2+, seven were 3+ and only four were 4+ positive. Conversely, all 57 FA were p27 positive, 53 were 4+, and four were 3+ positive. This difference in the grade of p27 staining between FVPC and FA was statistically significant (P < .001). This study shows a significant underexpression of p27 in FVPC compared with FA, suggesting that a decrease in p27 expression plays a more important role than overexpression of cyclins D1 and E alone in thyroid carcinogenesis and that p27 immunostaining may be helpful in the diagnosis of FVPC.

Topics: Adenocarcinoma, Follicular; Adenoma; Carcinoma, Papillary; Cell Cycle; Cell Cycle Proteins; Cyclin D1; Cyclin E; Cyclin-Dependent Kinase Inhibitor p27; Humans; Immunohistochemistry; Microtubule-Associated Proteins; Thyroid Neoplasms; Tumor Suppressor Proteins

Tumor cells often become resistant to the growth-inhibitory effects of transforming growth factor beta (TGF-beta). Recent studies have identified TGF-beta type II receptor (RII) mutations in a subset of cancers, including colon cancer. To evaluate the expression of TGF-beta RII in premalignant intestinal adenomas and the relationship with cell cycle regulation, we investigated the expression of TGF-beta RII, cyclin D1, and cyclin-dependent kinase 4 (Cdk4) in Min/+ mouse intestinal adenomas. Immunohistochemistry indicated that TGF-beta RII cytoplasmic immunoreactivity was undetectable in the proliferative crypt zones of the normal small intestinal and normal colonic epithelium but was abundant toward the villus tips of the normal small intestine and the lumenal third of the colonic glands. As was observed in the proliferating crypt zones, TGF-beta RII immunoreactivity was dramatically decreased or undetectable in all adenomas examined in comparison to the abundant levels in adjacent normal differentiated intestinal epithelium. TGF-beta RII mRNA was also reduced in the adenomas in comparison to normal mucosa as determined by reverse transcription-PCR. In an inverse distribution to TGF-beta RII, Cdk4 nuclear immunoreactivity was restricted to the crypt regions of the small and large intestine, whereas cyclin D1 immunoreactivity was uniformly absent in normal intestinal epithelium. For both cyclin D1 and Cdk4, protein and mRNA levels were increased in intestinal adenomas but not in normal intestinal epithelium as determined by immunohistochemistry, in situ hybridization, and reverse transcription-PCR. In summary, the lack of TGF-beta RII expression was associated with increased cyclin D1 and Cdk4 expression in Min/+ mouse intestinal adenomas. We hypothesize that the former may enable tumor cells to escape from the normal growth-constraining influence of TGF-beta, whereas the latter promotes inappropriate cell proliferation and adenoma progression.

Topics: Adenoma; Adenomatous Polyposis Coli Protein; Animals; Cyclin D1; Cyclin-Dependent Kinase 4; Cyclin-Dependent Kinases; Cyclins; Cytoskeletal Proteins; In Situ Hybridization; Intestinal Mucosa; Intestinal Neoplasms; Mice; Mice, Mutant Strains; Oncogene Proteins; Protein Serine-Threonine Kinases; Proto-Oncogene Proteins; Receptor, Transforming Growth Factor-beta Type II; Receptors, Transforming Growth Factor beta; RNA, Messenger; RNA, Neoplasm

Cyclin D1 gene amplification and/or overexpression occurs in several human cancers. The level of expression of cyclin D1 protein during the multistage process of human colon carcinogenesis was determined.. Cyclin D1 protein abundance was determined by immunostaining samples of normal colonic mucosa(n=23), transitional normal mucosa adjacent to adenomas or adenocarcinomas (n=41), hyperplastic polyps (n=8), adenomatous polyps (=35), and adenocarcinomas (n=27), using a polyclonal anti-human cyclin D1 antibody.. Cyclin D1 nuclear staining occurred in 30% of adenocarcinomas and 34% of adenomatous polyps but not in hyperplastic polyps or normal or transitional mucosa. Nuclear staining did not correlate with sex, age, size, or dysplasia of the adenomatous polyps or with differentiation and Dukes' staging of the adenocarcinomas. Left-sided colon neoplasms showed nuclear staining more frequently than those right-sided lesions. Diffuse or supranuclear cytoplasmic staining occurred in about one third of hyperplastic polyps, adenomas, and adenocarcinomas and in transitional mucosa adjacent to adenocarcinoma.. Increased nuclear expression of cyclin D1 occurs in around one third of colonic tumors as an early event during multistage process of colon carcinogenesis. Increased expression of cyclin D1 may perturb cell-cycle control in benign adenomas and thereby enhance tumor progression.

Topics: Adenocarcinoma; Adenoma; Adolescent; Adult; Aged; Cell Nucleus; Chi-Square Distribution; Colon; Colonic Polyps; Colorectal Neoplasms; Cyclin D1; Cyclins; Cytoplasm; Female; Humans; Immunohistochemistry; Intestinal Mucosa; Logistic Models; Male; Middle Aged; Oncogene Proteins

The cyclin D1 (PRAD1) oncogene is rearranged with the PTH gene and is transcriptionally activated in a subset of parathyroid adenomas. Because of heterogeneity in rearrangement breakpoints, the true percentage of adenomas with cyclin D1 deregulation is unknown. Overexpression of the cyclin D1 protein in parathyroid adenomas appears to be a unifying consequence of all cyclin D1 gene rearrangements and can, therefore, be examined to more comprehensively identify adenomas in which cyclin D1 is pathogenetically important. We studied cyclin D1 expression in 65 parathyroid adenomas (from 64 patients), 51 normal parathyroid glands (from the same patients), and 4 parathyroid carcinoma specimens (from 3 patients) using a microwave-enhanced immunohistochemical method and affinity-purified cyclin D1 polyclonal antiserum. When available, data on adenoma mass, intact PTH level, and concurrent serum calcium level were also collected. Twelve of the 65 adenomas (18%) showed diffuse nuclear staining of approximately 30-70% of the tumor cells. All 51 normal glands were negative, except 1 gland that showed scattered cells ( < 10%) with positive nuclear staining. In addition, scattered positive cells were seen in the compressed rim of histologically normal parathyroid tissue surrounding 2 adenomas that were cyclin D1 negative. No significant differences in adenoma mass, intact PTH levels, or concurrent calcium levels were found between positive and negative tumors. Two of 4 parathyroid carcinoma specimens from 2 of 3 patients showed strong nuclear staining for cyclin D1. Overexpression of the cyclin D1 oncogene in 18% of our cases, due to the cyclin D1/PTH translocation and/or other mechanisms, suggests that overexpressed cyclin D1 plays a role in the pathogenesis of a much larger proportion of parathyroid adenomas than previously appreciated. Cyclin D1 overexpression is a feature of typical parathyroid adenomas and is not confined to unusually large, symptom-causing adenomas as had been suggested by early DNA studies. Although only three patients with parathyroid carcinoma were studied, two of the patients' tumors stained for cyclin D1, raising the possibility that the frequency of cyclin D1 overexpression may be even greater in carcinomas. Cyclin D1 overexpression appears to highlight a central pathway in parathyroid neoplasia.

Topics: Adenoma; Adult; Aged; Aged, 80 and over; Calcium; Cyclin D1; Cyclins; Female; Gene Expression; Humans; Immunoenzyme Techniques; Male; Middle Aged; Oncogene Proteins; Parathyroid Hormone; Parathyroid Neoplasms

Colorectal cancer is the second leading cause of death from cancer in the United States. Continuous use of aspirin and other nonsteroidal anti-inflammatory drugs (NSAIDs) has been shown to reduce the risk of colorectal cancer in humans by 40-50%. Patients with familial adenomatous polyposis who take NSAIDs, such as sulindac, undergo a regression of intestinal adenomas. Rodents exposed to carcinogens that cause colon cancer have a 50-60% reduction in the size and number of colonic tumors when treated continuously with NSAIDs. One common target for these drugs is prostaglandin endoperoxide synthase, also referred to as cyclooxygenase (COX). We and others have shown recently that COX-2 levels are increased dramatically in 85-90% of human colorectal adenocarcinomas and in 40-50% of colonic adenomas. We prepared intestinal epithelial cells that express the COX-2 gene permanently and found that they have altered adhesion properties and resist undergoing apoptosis. We report here that these cells also have a 3-fold increase in the duration of G1, lower levels of cyclin D1 protein, and a marked decrease in retinoblastoma kinase activity associated with cyclin-dependent kinase 4. The delay in G1 transit may relate to the resistance of these cells to undergo programmed cell death, which could affect their tumorigenic potential.

Topics: Adenoma; Animals; Anti-Inflammatory Agents, Non-Steroidal; Anticarcinogenic Agents; Aspirin; Cell Line; Colonic Neoplasms; Colorectal Neoplasms; Cyclin D1; Cyclin-Dependent Kinase 4; Cyclin-Dependent Kinases; Cyclins; DNA; Epithelium; G1 Phase; Humans; Intestines; Kinetics; Oncogene Proteins; Open Reading Frames; Prostaglandin-Endoperoxide Synthases; Proto-Oncogene Proteins; Rats; Recombinant Proteins; Retinoblastoma Protein; Time Factors; Transfection; United States

PRAD1 (cyclin D1) has been implicated in the molecular pathogenesis of a variety of tumors, including parathyroid adenomas, t(11;14)-bearing B-lymphoid tumors, and breast cancer. The sequence of the overexpressed PRAD1 genes has been directly analyzed in only two tumor specimens, a benign parathyroid adenoma and a malignant centrocytic lymphoma. Thus, little is known about PRAD1 sequence in the vast majority of human primary tumors, including breast cancers. Using single-strand conformational polymorphism (SSCP) analysis, we have examined the coding region of the PRAD1 gene in 30 primary breast cancers and 25 parathyroid adenomas. Polymerase chain reaction (PCR)-SSCP analysis of the coding region of exons 1-5 of the PRAD1 gene did not reveal any tumor-specific mutations. During the course of screening for mutations, we found and established the sequence variants of a new DNA polymorphism at codon 241 within exon 4 of the PRAD1 gene. Since this polymorphism is located within the coding region of the PRAD1 gene, it will allow determination of allele-specific expression of the gene and the detection of allele imbalance. At least in breast and parathyroid neoplasms, overexpression of the wild-type PRAD1 sequence, rather than point mutational activation, appears to be the predominant mechanism by which PRAD1 exerts its oncogenic action.

Topics: Adenoma; Base Sequence; Breast Neoplasms; Cyclin D1; Cyclins; Exons; Humans; Molecular Sequence Data; Oligonucleotide Probes; Oncogene Proteins; Oncogenes; Parathyroid Neoplasms; Point Mutation; Polymorphism, Genetic

PRAD1 (previously D11S287) is a putative proto-oncogene at 11q13, activated by overexpression through gene rearrangement or gene amplification in several types of human tumors including parathyroid adenomas, centrocytic lymphomas and other B-cell tumors with t(11;14), and breast cancers. PRAD1 (also CCND1) encodes cyclin D1, which may regulate the G1-S phase transition in the cell cycle. Here, we report the cloning and characterization of the chromosomal PRAD1/cyclin D1 gene and the sequence of its promoter region. The gene spans about 15 kb and has 5 exons; its promoter region has Sp1 binding sites and no obvious TATA box, characteristics of housekeeping genes and growth-regulating genes. Furthermore, an E2F binding motif present close to the major transcription start site may be involved in cell cycle-dependent expression of this gene. We also report the sequence of DNAs spanning joining regions of a reciprocal parathyroid hormone/PRAD1 gene rearrangement in a parathyroid adenoma. Comparison with normal sequences suggests that the rearrangement was not a simple break-and-ligate event, but rather involved multiple steps, including two microdeletions and a microinversion. Very short sequences conserved near the breakpoints and symmetrical elements in the eventually inverted DNA segment might have played a role in this illegitimate complex recombination, which may have similarities with a constitutional translocation in Duchenne muscular dystrophy.

Topics: Adenoma; Amino Acid Sequence; Base Sequence; Cloning, Molecular; Cyclin D1; Cyclins; DNA, Neoplasm; Gene Rearrangement; Humans; Molecular Sequence Data; Oncogene Proteins; Parathyroid Hormone; Parathyroid Neoplasms; Promoter Regions, Genetic; Proto-Oncogene Mas; Proto-Oncogenes; Sequence Homology, Nucleic Acid

PRAD1 (cyclin D1) is a recently identified member of the family of cyclin genes, believed to play roles in regulating transitions through the cell cycle. The PRAD1 gene, located at 11q13, has been implicated in the pathogenesis of a variety of tumors, including parathyroid adenomas, t(11;14) bearing B-lymphoid tumors (particularly centrocytic lymphomas) where it is highly likely to be the BCL1 oncogene, and possibly in breast carcinomas and squamous cell cancers of the head and neck as well. PRAD1's tumorigenic influence appears to be effected through overexpression of its normal-sized transcript, but it has not been established whether the transcript's coding sequence is normal or contains oncogenic mutations. We have sequenced the coding region of the overexpressed PRAD1 transcript from two primary tumors with clonal PRAD1 region rearrangements: a benign parathyroid adenoma and a malignant centrocytic lymphoma. Each sequence is identical to the normal PRAD1 cDNA sequence, and presumably encodes normal PRAD1 protein. Thus, PRAD1 likely functions as a direct-acting oncogene whose rearrangement in tumors leads to overexpression or deregulated expression of its normal protein product.

Topics: Adenoma; Base Sequence; Cyclin D1; Cyclins; Gene Expression; Gene Rearrangement; Humans; Lymphoma; Molecular Sequence Data; Oncogene Proteins; Oncogenes; Parathyroid Neoplasms

We have previously identified a candidate oncogene (PRAD1 or D11S287E) on chromosome 11q13 which is clonally rearranged with the parathyroid hormone locus in a subset of benign parathyroid tumours. We now report that a cloned human placental PRAD1 complementary DNA encodes a protein of 295 amino acids with sequence similarities to the cyclins. Cyclins can form a complex with and activate p34cdc2 protein kinase, thereby regulating progress through the cell cycle. PRAD 1 messenger RNA levels vary dramatically across the cell cycle in HeLa cells. Addition of the PRAD1 protein to interphase clam embryo lysates containing inactive p34cdc2 kinase and lacking endogenous cyclins allows it to be isolated using beads bearing p13suc1, a yeast protein that binds cdc2 and related kinases with high affinity and coprecipitates kinase-associated proteins. Addition of PRAD1 also induces phosphorylation of histone H1, a preferred substrate of cdc2. These data suggest that PRAD1 encodes a novel cyclin whose overexpression may play an important part in the development of various tumours with abnormalities in 11q13.

Topics: Adenoma; Amino Acid Sequence; Animals; Base Sequence; Bivalvia; Cell Cycle; Chromosomes, Human, Pair 11; Cyclin D1; Cyclins; DNA; Gene Expression; Humans; Molecular Sequence Data; Oncogene Proteins; Oncogenes; Parathyroid Neoplasms; Proto-Oncogene Proteins; RNA, Messenger; Transfection

Topics: Adenoma; Amino Acid Sequence; Animals; Cell Cycle; Cyclin D1; Cyclins; DNA, Neoplasm; Humans; Molecular Sequence Data; Oncogene Proteins; Oncogenes; Parathyroid Neoplasms; Sequence Homology, Nucleic Acid