cyclin-d1 and Carcinoma--Large-Cell

Large-cell neuroendocrine carcinoma (LCNEC) and small-cell carcinoma (SCLC) of lung encompass high-grade neuroendocrine tumour category and share several fundamental features. As both tumours may respond to different treatment modalities and show unique molecular alterations distinction between the two is clinically relevant, but can be challenging due to sampling and fixation issues and shared morphological features.. Surgically resected primary SCLC (n = 129) and LCNEC (n = 27) were immunohistochemically stained with Rb1, cyclin D1 and p16 using tissue microarray (TMA), and expression patterns of the proteins were compared between the two to identify the discriminatory pattern.. All markers had high diagnostic accuracy; Rb1 was the highest followed by p16 and cyclin D1. The majority of SCLC had the pattern Rb1-/p16+/cyclin D1- and more than half of LCNEC had Rb1+/p16-/cyclin D1+. Overall, the expression pattern Rb1- and cyclin D1- was strongly associated with the diagnosis of SCLC, while the pattern Rb1+ and/or cyclin D1+ was strongly associated with LCNEC. The use of this simplified expression pattern leads to a diagnostic accuracy of 97.3%. p16 did not add to further discrimination. The heterogeneity in Rb1, cyclin D1 and p16 expression was insignificant in SCLCs compared with LCNECs.. Use of Rb1, cyclin D1 and p16 immunohistochemistry can distinguish the two with high accuracy. Notably, the Rb1-/cyclin D1- pattern in given tumour sample would confirm the diagnosis of SCLC. Our results could be extrapolated and applied to routine diagnostic samples such as biopsies and cytology samples.

Topics: Carcinoma, Large Cell; Carcinoma, Neuroendocrine; Carcinoma, Small Cell; Cyclin D1; Genes, p16; Humans; Immunohistochemistry; Lung; Lung Neoplasms; Retinoblastoma Binding Proteins; Small Cell Lung Carcinoma; Ubiquitin-Protein Ligases

Cyclin D1, an oncogenic G1 cyclin, and YB-1, a transcription factor involved in cell growth, are both over-expressed in several human cancers. In human lung cancer, the functional association between YB-1 and cyclin D1 has never been elucidated. In this study, we show YB-1 is involved in the transcription of cyclin D1 in human lung cancer. Depletion of endogenous YB-1 by siRNA inhibited progression of G1 phase and down-regulated both the protein and mRNA levels of cyclin D1 in human lung cancer cells. Forced over-expression of YB-1 with a cyclin D1 reporter plasmid increased luciferase activity, and ChIP assay results showed YB-1 bound to the cyclin D1 promoter. Moreover, the amount of YB-1 mRNA positively correlated with cyclin D1 mRNA levels in clinical non-small-cell lung cancer (NSCLC) specimens. Immunohistochemical analysis also indicated YB-1 expression correlated with cyclin D1 expression in NSCLC specimens. In addition, most of the cases expressing both cyclin D1 and CDC6, another molecule controlled by YB-1, had co-existing YB-1 over-expression. Together, our results suggest that aberrant expression of both cyclin D1 and CDC6 by YB-1 over-expression may collaboratively participate in lung carcinogenesis.

Topics: Adenocarcinoma; Adult; Aged; Aged, 80 and over; Carcinoma, Large Cell; Carcinoma, Non-Small-Cell Lung; Carcinoma, Squamous Cell; Cell Cycle Proteins; Cell Line, Tumor; Cell Proliferation; Cyclin D1; Female; Gene Knockdown Techniques; Humans; Lung Neoplasms; Male; Middle Aged; Nuclear Proteins; Promoter Regions, Genetic; RNA, Messenger; Y-Box-Binding Protein 1

Caveolin-1 (CAV-1), one component of caveolae, involves in multiple cellular processes and signal transductions. We previously showed that the expression of CAV-1 gene in NCI-H446 cells inhibited cell proliferation and promoted cell metastasis. Here we explore the function of CAV-1 on tumor growth and metastasis by using NCI-H460 in vitro. First, we established NCI-H460 cell line, which CAV-1 was stably knockdown. Then we investigated the effects of CAV-1 on the morphology, proliferation, cell cycle and metastasis potential for NCI-H460 cell by crystal violet stains, CCK-8, colony formation, flow cytometry, scratch-wound assay and transwell assay. Western blot was used to examine the expression changes of cyclin D1, PCNA, E-cadherin and β-catenin. Our results showed stable knockdown of CAV-1 inhibited the proliferation of NCI-H460 cells. Cell cycle of the transfected cells was arrested in G1/S phase and the expressions of cyclin D1 and PCNA protein were downregulated. Downregulation of CAV-1 promoted the migration and invasion abilities of NCI-H460 cells in vitro. The expression of β-catenin increased and the level of E-cadherin decreased. In summary, our findings provide experimental evidence that CAV-1 may function as a proproliferative and antimetastatic gene in NCI-H460 cell line.

Topics: Antigens, CD; beta Catenin; Cadherins; Carcinoma, Large Cell; Caveolin 1; Cell Cycle; Cell Line, Tumor; Cell Movement; Cell Proliferation; Cell Shape; Cyclin D1; Gene Expression Regulation, Neoplastic; Gene Silencing; Humans; Lung Neoplasms; Neoplasm Proteins; Proliferating Cell Nuclear Antigen; Recombinant Proteins; RNA, Messenger; RNA, Small Interfering; Tumor Stem Cell Assay

Correct diagnosis of pleural effusion (PE) as either benign or malignant is crucial, although conventional cytological evaluation is of limited diagnostic accuracy, with relatively low sensitivity rates.. We identified biological markers accurately detected in a simple PE examination. We analysed data from 19 patients diagnosed with lung cancer (nine adeno-Ca, five non-small-cell Ca (not specified), four squamous-cell Ca, one large-cell Ca) and 22 patients with benign inflammatory pathologies: secondary to trauma, pneumonia or TB.. Pleural effusion concentrations of seven analysed biological markers were significantly lower in lung cancer patients than in benign inflammatory patients, especially in matrix metalloproteinase (MMP)-9, MMP-3 and CycD1 (lower by 65% (P<0.000003), 40% (P<0.0007) and 34% (P<0.0001), respectively), and in Ki67, ImAnOx, carbonyls and p27. High rates of sensitivity and specificity values were found for MMP-9, MMP-3 and CycD1: 80 and 100%; 87 and 73%; and 87 and 82%, respectively.. Although our results are of significant merit in both the clinical and pathogenetic aspects of lung cancer, further research aimed at defining the best combination for marker analysis is warranted. The relative simplicity in analysing these markers in any routine hospital laboratory may result in its acceptance as a new diagnostic tool.

Topics: Adenocarcinoma; Aged; Biomarkers; Carcinoma, Large Cell; Carcinoma, Non-Small-Cell Lung; Carcinoma, Squamous Cell; Cyclin D1; Female; Humans; Ki-67 Antigen; Lung Neoplasms; Male; Matrix Metalloproteinase 3; Matrix Metalloproteinase 9; Middle Aged; Pleural Effusion; Pneumonia

A large group of interacting molecular factors, involved in epithelial-mesenchymal transition, epidermal growth factor receptor (EGFR) signaling, and G1 mitotic phase, are shown to play an important role in cancerogenesis and progression of non-small cell lung cancer (NSCLC). Since success concerning potential correlations, structural and numeric gene aberrations, and biological risk assessment of these molecular factors are still lacking, combined analysis of a multitude of intertwined factors is currently a promising approach.. Cyclins (D1, D2, D3, and E), p21, p27, EGFR, Snail, E-cadherin, beta-catenin, phosphatidylinositol-3' kinase, phosphatase and tensin homologue, phosphorylated Akt, and phosphorylated signal transducer, and activator of transcription-3 were analyzed by immunohistochemistry in 405 surgically resected NSCLC, using a standardized tissue microarray platform. In addition, the gene status of EGFR and cyclin D1 was examined by fluorescence in situ hybridization. Extensive clinical data were acquired, enabling detailed clinicopathologic correlation during a postoperative follow-up period of up to 14 years.. The protein overexpressions of nuclear p27, cyclin D1, cyclin D3, E-cadherin, and EGFR as assessed by immunohistochemistry were all associated with a significant reduction in overall survival time. In addition, cyclin D1 proved especially important, being the only independent molecular tumor-related factor with prognostic significance by multivariable analysis. In analogy to EGFR, recurrent numeric gene aberrations, particularly high-level amplifications, of cyclin D1 were obvious.. The results emphasize that deregulation of controlling factors of the early G1 phase is of significant oncogenic relevance and may represent a potential treatment target in NSCLC.

Topics: Adenocarcinoma; Adult; Aged; Aged, 80 and over; Carcinoma, Large Cell; Carcinoma, Non-Small-Cell Lung; Carcinoma, Squamous Cell; Cyclin D1; Cyclin D3; Cyclin-Dependent Kinase Inhibitor p27; Female; Humans; Immunoenzyme Techniques; In Situ Hybridization, Fluorescence; Intracellular Signaling Peptides and Proteins; Lung Neoplasms; Male; Middle Aged; Mitosis; Prognosis; Retrospective Studies; Survival Rate; Tissue Array Analysis; Young Adult

Stage IIIA non-small cell lung cancer (NSCLC) with ipsilateral mediastinal lymph node metastases (N2) is a heterogeneous disease with differing prognoses. In this study, we retrospectively investigated the prognostic value of the expression of 10 molecular markers in 87 patients with stage IIIA pN2 NSCLC treated with radical surgery.. Primary tumor tissue microarrays (TMAs) were constructed and sections used for immunohistochemical analysis of epidermal growth factor receptor, ErbB-2, c-kit, cyclooxygenase-2, survivin, bcl-2, cyclin D1, cyclin B1, metalloproteinase (MMP)-2, and MMP-9. Univariate and multivariate analyses and unsupervised hierarchical clustering analysis of clinical pathologic and immunostaining data were performed.. Bcl-2 (p < 0.0001) and cyclin D1 (p = 0.015) were more highly expressed in squamous cell carcinoma (SCC), whereas MMP-2 (p = 0.009), MMP-9 (p = 0.005), and survivin (p = 0.032) had increased expression in other histologic subtypes. In univariate analysis, SCC histology and cyclin D1 expressions were favorable prognostic factors (p = 0.015 and p < 0.0001, respectively); by contrast, MMP-9 expression was associated with worse prognosis (p = 0.042). In multivariate analysis, cyclin D1 was the only positive prognostic factor (p < 0.0001). Unsupervised hierarchical clustering analysis of TMA immunostaining data identified five distinct clusters. They formed two subsets of patients with better (clusters 1 and 2) and worse (clusters 3, 4, and 5) prognoses, and median survival of 51 and 10 months, respectively (p < 0.0001). The better prognosis subset mainly comprised patients with SCC (80%).. Hierarchical clustering of TMA immunostaining data using a limited set of markers identifies patients with stage IIIA pN2 NSCLC at high risk of recurrence, who may benefit from more aggressive treatment.

Topics: Adenocarcinoma; Adult; Aged; Biomarkers, Tumor; Carcinoma, Large Cell; Carcinoma, Non-Small-Cell Lung; Carcinoma, Squamous Cell; Cluster Analysis; Cyclin B1; Cyclin D1; Cyclooxygenase 2; ErbB Receptors; Female; Humans; Immunoenzyme Techniques; Inhibitor of Apoptosis Proteins; Lung Neoplasms; Male; Matrix Metalloproteinase 2; Matrix Metalloproteinase 9; Microtubule-Associated Proteins; Middle Aged; Neoplasm Staging; Prognosis; Prospective Studies; Proto-Oncogene Proteins c-bcl-2; Receptor, ErbB-2; Retrospective Studies; Survival Rate; Survivin; Tissue Array Analysis

Patients who have pathologic N2 (pN2) nonsmall cell lung cancer (pN2 NSCLC) represent a heterogeneous group with regard to prognosis and treatment. Molecular features of NSCLC seem to be of interest. For the current study, to select an appropriate therapeutic strategy for each patient, patients with N2 NSCLC were stratified into homogenous subgroups according to the expression profiles of cell cycle-related markers.. The expression levels of retinoblastoma protein (pRb), cyclin D1, p16, p53, and p21 proteins and values of the Ki-67 labeling index were evaluated in 61 primary surgically resected tumor specimens from patients with pN2 NSCLC using immunohistochemistry. The prognostic impact of these markers on overall survival was analyzed in both univariate and multivariate analyses.. In univariate analysis, p21, p16, and Ki-67 were correlated significantly with survival. In multivariate analysis, only p21 and p16 influenced survival. Indeed, the group of patients with pN2 NSCLC who were positive for p21 and p16 had the most favorable overall survival (P = .001) and were correlated significantly with the clinical lymph node (cN) status (cN2 disease; P = .008). Moreover, no significant difference in survival was observed between patients with cN0/cN1 disease and patients with cN2 disease within the group (P = .4333).. Loss of control of cell-cycle checkpoints is a common occurrence in pN2 NSCLC. Functional cooperation between different cell-cycle regulators constitutes another level of regulation in cell growth control and tumor suppression. Preoperative patients with pN2 NSCLC, even those with cN2 disease, who have positive p21 and p16 protein expression in their primary tumors are expected to have a favorable postoperative prognosis and may be candidates for primary resection.

Topics: Adenocarcinoma; Biomarkers, Tumor; Carcinoma, Large Cell; Carcinoma, Non-Small-Cell Lung; Carcinoma, Squamous Cell; Cell Cycle Proteins; Cyclin D1; Cyclin-Dependent Kinase Inhibitor p16; Cyclin-Dependent Kinase Inhibitor p21; Female; Gene Expression Regulation, Neoplastic; Humans; Immunoenzyme Techniques; Lung Neoplasms; Male; Middle Aged; Neoplasm Staging; Prognosis; Retinoblastoma Protein; Retrospective Studies; Survival Rate; Tumor Suppressor Protein p53

A total of 111 pulmonary neuroendocrine tumors comprising 13 typical carcinoids, five atypical carcinoids, 44 large-cell neuroendocrine carcinomas and 49 small-cell carcinomas were immunohistochemically studied for dysregulated cyclin B1 expression and disruption of the Rb/p16/cyclin D1 pathway (Rb pathway), and the results were correlated with tumor proliferation activity and clinical outcome. Overexpression of cyclins B1 and D1, respectively, was detected in no and 15% typical carcinoids, 20 and 20% atypical carcinoids, 84 and 32% large-cell neuroendocrine carcinomas, 84 and 10% small-cell carcinomas. Loss of Rb and p16 expression, respectively, was observed in no and 14% typical carcinoids, no and 40% atypical carcinoids, 49 and 18% large-cell neuroendocrine carcinomas, 84 and 8% small-cell carcinomas. In summary, 29% typical carcinoids, 20% atypical carcinoids, 78% large-cell neuroendocrine carcinomas and 93% small-cell carcinomas had Rb pathway aberrations. Rb pathway aberration was mostly attributed to Rb loss in small-cell carcinomas, while p16 loss and/or cyclin D1 overexpression besides Rb loss also played an important role in large-cell neuroendocrine carcinomas, while cyclin D1 overexpression was the only cause of Rb pathway aberration in carcinoid tumors. Thus, both cyclin B1-associated G2/M arrest and Rb-mediated G1 arrest are consistently compromised in high-grade large-cell neuroendocrine carcinoma and small-cell carcinoma, but are generally intact or occasionally altered in carcinoid tumor; the mechanisms involved in Rb pathway aberration among the tumor categories are different, reflecting a genetic divergence among the individual tumor categories. Cyclin B1 expression closely correlated with the Ki-67 labeling index either in the individual tumor categories or overall tumors (P < 0.0001, r = 0.742), suggesting that cyclin B1 is one of the key factors regulating cell proliferation in pulmonary neuroendocrine tumors. Neither cyclins B1 and D1, Rb, p16, nor Ki-67 correlated with patient survival in individual tumor categories, suggesting that the prognostic significance of these factors is tumor-type specific.

Topics: Biomarkers, Tumor; Carcinoid Tumor; Carcinoma, Large Cell; Carcinoma, Small Cell; Cyclin B; Cyclin B1; Cyclin D1; Cyclin-Dependent Kinase Inhibitor p16; Humans; Immunohistochemistry; Ki-67 Antigen; Lung Neoplasms; Neuroendocrine Tumors; Retinoblastoma Protein; Signal Transduction; Survival Analysis

Recently, the authors identified molecular signatures and pathways associated with nonsmall cell lung carcinoma histology and lung development. They hypothesized that genetic classifiers of histology would provide insight into lung tumorigenesis and would be associated with clinical outcome when evaluated in a broader set of specimens.. Associations between patient survival and immunostaining for 11 representative histologic classifiers (epidermal growth factor receptor [EGFR], CDK4, syndecan-1, singed-like, TTF-1, keratin 5, HDAC2, docking protein 1, integrin alpha3, P63, and cyclin D1) were examined using a tissue microarray constructed from nonsmall cell lung carcinoma specimens.. Sixty-three tumors were examined, including 43 adenocarcinomas, 11 large cell carcinomas, and 9 squamous cell carcinomas. Sixty-three percent of tumors were clinical Stage I lesions, and 37% were Stage II-III lesions. In a multivariate analysis that controlled for age, gender, and race, syndecan-1 expression was found to be associated with a significant reduction in the risk of death (hazard ratio, 0.31 [95% confidence interval, 0.18-0.87]; P < 0.05). Multivariate analysis also indicated that EGFR expression was associated with a significant reduced risk of death.. The authors demonstrated that expression of either of the nonsmall cell lung carcinoma subtype classifiers syndecan-1 and EGFR was associated with a 30% reduction in the risk of death, with this reduction being independent of histology and other confounders. The results of the current study suggest that loss of expression of these histologic classifiers is associated with biologic aggressiveness in lung tumors and with poor outcome for patients with such tumors. If their significance can be validated prospectively, these biomarkers may be used to guide therapeutic planning for patients with nonsmall cell lung carcinoma.

Topics: Adenocarcinoma; Aged; Carcinoma, Large Cell; Carcinoma, Non-Small-Cell Lung; Carcinoma, Squamous Cell; Cyclin D1; Cyclin-Dependent Kinase 4; Cyclin-Dependent Kinases; ErbB Receptors; Female; Histone Deacetylase 2; Histone Deacetylases; Humans; Immunohistochemistry; Integrin alpha Chains; Keratin-5; Keratins; Lung Neoplasms; Male; Membrane Glycoproteins; Membrane Proteins; Multivariate Analysis; Nuclear Proteins; Proteoglycans; Proto-Oncogene Proteins; Repressor Proteins; Syndecan-1; Syndecans; Thyroid Nuclear Factor 1; Transcription Factors

Molecular analysis of microdissected tissue samples is used for analyzing tissue heterogeneity of histological specimens. We have developed a rapid one-step microdissection technique, which was applied for the selective procurement of tissue areas down to a minimum of 10 cell profiles. The special features of our microdissection system consist of an ultrasonically oscillating needle and a piezo-driven micropipette. The validity of this technique is demonstrated in human lung large-cell carcinoma by real-time quantitative reverse transcriptase-polymerase chain reaction assays of vimentin, cyclin D1, and carcinoembryonic antigen after linear RNA amplification. mRNA expression values of microdissected samples scattered around those of bulk tumor tissue and showed differential mRNA expression between samples of tumor parenchyma and supportive stromal cells for vimentin and carcinoembryonic antigen as confirmed by immunohistochemistry. In conclusion, this procedure requires simple equipment, is easily performed, and delivers microdissected tissue samples of oligocellular clusters suitable for further molecular analysis.

Topics: Carcinoembryonic Antigen; Carcinoma, Large Cell; Colon; Cyclin D1; Dissection; Humans; Immunohistochemistry; Lung Neoplasms; Needles; Reverse Transcriptase Polymerase Chain Reaction; RNA, Neoplasm; Transcription, Genetic; Ultrasonics; Vimentin

Pulmonary large-cell neuroendocrine carcinoma (LCNEC) is a newly proposed clinicopathologic entity; a few cases of LCNEC have been reported in other sites, such as the uterine cervix and the thymus. In the salivary glands, LCNEC is extremely rare and is not recognized as a specific entity in the World Health Organization classification. We retrospectively reviewed from our files 1675 cases of surgically resected primary parotid gland tumors and found 2 cases of LCNEC that fulfilled the criteria of pulmonary LCNEC. These cases occurred in 72- and 73-year-old men who had short histories of enlarging parotid gland tumors. The tumors were composed of large cells that exhibited organoid, solid, trabecular, and rosette-like growth patterns with a high mitotic rate and a conspicuous tendency for necrosis. The tumor cells were polygonal and characterized by a moderate nuclear:cytoplasmic ratio, coarse chromatin, and conspicuous nucleoli. Immunohistochemical examination revealed that the tumor cells were positive for six general neuroendocrine markers, cytokeratin, p53, bcl-2, epidermal growth factor receptor, and cyclin D1. Markedly reduced expressions of p21Waf1 and p27Kip1 were also noticed. The Ki-67 labeling index was more than 50% in both cases. One case showed loss of heterozygosity at TP53 accompanied by a p53 gene point mutation. Loss of heterozygosity at chromosome 9p21 was detected in both cases; one was accompanied by a p16 gene silent point mutation. Both patients died of the disease, with recurrence 5 months and 4 years after surgery, respectively. These findings indicate that LCNEC is a rare but distinct salivary gland tumor with highly aggressive biologic behavior. Multiple alterations of cell cycle regulators and tumor suppressor genes may play an important role in presenting the biologic characteristics of this rare parotid gland tumor.

Topics: Aged; Base Sequence; Carcinoma, Large Cell; Carcinoma, Neuroendocrine; Carcinoma, Non-Small-Cell Lung; Cyclin D1; Diagnosis, Differential; DNA Mutational Analysis; DNA, Neoplasm; ErbB Receptors; Humans; Keratins; Ki-67 Antigen; Loss of Heterozygosity; Lung Neoplasms; Male; Microscopy, Electron; Parotid Neoplasms; Point Mutation; Proto-Oncogene Proteins c-bcl-2; Tumor Suppressor Protein p53

Ex-chromate workers are frequently afflicted with lung cancers, especially central-type squamous cell carcinomas (SCCs) of the lung. However, little is known about the molecular and cellular biologic characteristics of chromate-induced lung cancers. We investigated expression of cyclin D1, bcl-2, and p53 proteins in chromate-induced lung cancers by immunohistochemistry, compared with those in lung cancers from nonexposed individuals and those in individuals with pneumoconiosis. Of 19 chromate-induced lung cancers, 16 tumors were SCCs, including 11 central and 5 peripheral types. Eleven (69%) of 16 chromate SCCs showed cyclin D1 expression. In contrast, cyclin D1 expression was observed in only 3 (12%) of 26 SCCs from nonexposed individuals and 6 (16%) of 37 SCCs that developed in patients with pneumoconiosis, respectively. The frequency of cyclin D1 expression proved to be significantly higher in chromate-induced SCCs than in SCCs from nonexposed individuals and from those with pneumoconiosis (P < .001). When comparisons were extended to all histologic types of lung cancer, cyclin D1 expression was observed significantly more often in chromate-induced lung cancers than in lung cancers from nonexposed subjects and those from patients with pneumoconiosis (11 [58%] of 19 v 5 [10%] of 52, P < .001, and 7 [11%] of 63, P < .001, respectively). Frequencies of bcl-2 and p53 expression were not significantly different among lung cancers from ex-chromate workers, nonexposed individuals and those with pneumoconiosis. The current study suggests that cyclin D1 expression may be involved in the development of chromate-induced lung cancers, although its underlying mechanism remains to be determined.

Topics: Adenocarcinoma; Carcinoma, Large Cell; Carcinoma, Small Cell; Carcinoma, Squamous Cell; Chromates; Cyclin D1; Head and Neck Neoplasms; Humans; Immunohistochemistry; Lung Neoplasms; Occupational Exposure; Proto-Oncogene Proteins c-bcl-2; Smoking; Tumor Suppressor Protein p53

Aberrations in the pathway composed of p16, cyclin D1/CDK4,6 and pRb (pRb pathway) which controls the transition from G1 to S phase occur frequently in various types of tumors. In the present study we analyzed immunohistochemically the expression of pRb, p16 and cyclin D1 in 1 12 primary non-small cell lung carcinomas (NSCLC). Loss of expression of pRb and p16 proteins was demonstrated in 15/112 cases and 64/112 cases, respectively. Inverse expression of pRb and p16 proteins was observed in 61 cases and was statistically correlated with advanced stage of the disease (p=0.03). Overexpression of cyclin D1 was detected in 34 cases and was more frequently observed in stage I than in stage III of the disease (p=0.02). Concomitant overexpression of cyclin D1 and lack of p16 was observed in 57% of cyclin D1-positive tumors. In summary, 82 of 112 analyzed cases showed an aberrant expression of at least one of the investigated proteins. These results indicate that although pRb protein expression is altered only in a small percentage of NSCLCs, the pRb pathway is disrupted very frequently in this type of tumor. There were no statistically significant correlations between changes in protein expression and histological type of tumor, gender, smoking habits and occupation of patients.

Topics: Adenocarcinoma; Adult; Aged; Carcinoma, Large Cell; Carcinoma, Non-Small-Cell Lung; Carcinoma, Squamous Cell; Cyclin D1; Cyclin-Dependent Kinase Inhibitor p16; Female; Humans; Immunohistochemistry; Lung Neoplasms; Male; Middle Aged; Poland; Retinoblastoma Protein; Smoking

The pathway consisting of retinoblastoma protein (pRB), cyclin D1 and p16 (RB pathway) which is involved in the phosphorylation of pRB plays an important role in G1/S progression. The disruption of this RB pathway has been reported in several types of human neoplasm. An immunohistochemical study of 101 non-small-cell lung cancers (NSCLCs) showed loss of p16 is in 47 tumors (46.5%) and loss of pRB in 42 tumors (41.6%). In 79 of 101 NSCLCs (78.2%), the expression of p16 and pRB was complementary (p < 0.0001). Methylation of the cdkn2 gene was detected in 50% of p16-negative tumors and in 11% of p16-positive tumors. Aberrant expression of cyclin D1 was found in 45 tumors (44.5%). The cyclin-D1-positive tumors had significantly higher Ki-67 indices than the cyclin-D1-negative tumors irrespective of the tumor p16 or pRB expression. Thus, 91 (90%) of 101 NSCLCs showed disturbed expression of at least 1 of the 3 components of the RB pathway. Our results suggest that the disruption of the RB pathway plays an important role in tumorigenesis in NSCLCs and that increased cyclin-D1 expression leads to strong proliferative activity which may over-ride the suppressive effect of p16 and pRB.

Topics: Adenocarcinoma; Carcinoma, Large Cell; Carcinoma, Non-Small-Cell Lung; Carcinoma, Squamous Cell; Cell Cycle; Cell Division; Cyclin D1; Cyclin-Dependent Kinase Inhibitor p16; Female; Humans; Immunohistochemistry; Ki-67 Antigen; Lung Neoplasms; Male; Neoplasm Staging; Polymerase Chain Reaction; Polymorphism, Single-Stranded Conformational; Retinoblastoma Protein

To observe the expression of p16, pRb, cdk4 and cyclinD1 in non-small cell lung cancers, 104 cases of resected lung cancers were collected, which included squamous cell carcinomas, adenocarcinomas and large cell carcinomas. Immunohistochemistry assay was carried out. The results showed that 67% of squamous cell carcinomas and 46% of adenocarcinomas expressed p16, 64% of squamous cell carcinomas and 85% of adenocarcinomas expressed pRb and 66% of cancers expressed p16 or pRb. About 70% of the tumors expressed cyclinD1. More than 90% of the tumors expressed cdk4 and there was an increased trend with decreasing differentiation of both squamous cell carcinomas and adenocarcinomas. Sixty-seven percent of the highly differentiated and 100% of the poorly differentiated squamous cell carcinomas expressed cdk4. The aberrant p16 and pRb gene product expression played a significant role in the development and histological subtype of lung cancers by conditioning the biological behavior of NSCLC. cdk4 was an important factor in histological differentiation.

Topics: Adenocarcinoma; Carcinoma, Large Cell; Carcinoma, Non-Small-Cell Lung; Carcinoma, Squamous Cell; Cyclin D1; Cyclin-Dependent Kinase 4; Cyclin-Dependent Kinase Inhibitor p16; Cyclin-Dependent Kinases; Humans; Lung Neoplasms; Neoplasm Proteins; Proto-Oncogene Proteins; Retinoblastoma Protein