big-gastrin and Adenocarcinoma

Staging of colorectal cancer often fails to discriminate outcomes of patients with morphologically similar tumours that exhibit different clinical behaviours. Data from several studies suggest that the gastrin family of growth factors potentiates colorectal cancer tumourigenesis. The aim of this study was to investigate whether progastrin expression may predict clinical outcome in colorectal cancer.. Patients with colorectal adenocarcinoma of identical depth of invasion who had not received neoadjuvant therapy were included. The patients either had stage IIa disease with greater than 3-year disease-free survival without adjuvant therapy or stage IV disease with liver metastases on staging CT. Progastrin expression in tumour sections was scored with reference to the intensity and area of immunohistochemical staining.. Progastrin expression by stage IV tumours was significantly greater than stage IIa tumours with mean progastrin immunopositivity scores of 2.1 ± 0.2 versus 0.5 ± 0.2, respectively (P < 0.001).. This is the first study to show that progastrin expression may be predictive of aggressive tumour behaviour in patients with colorectal cancer and supports its clinical relevance and potential use as a biomarker.

Topics: Adenocarcinoma; Aged; Biomarkers, Tumor; Colorectal Neoplasms; Female; Gastrins; Humans; Liver Neoplasms; Male; Middle Aged; Neoplasm Staging; Protein Precursors

The gastrin and the gastrin/CCK-B receptor genes are co-expressed in several carcinomas. The primary translational product, progastrin, however, is processed to several peptides of which only those that are α-amidated at their C-terminus are receptor ligands. So far, characterization of the progastrin-derived peptides in gastric cancer has not been reported. The authors therefore examined the molecular nature of gastrin and its receptor in human gastric carcinomas.. Twenty patients with adenocarcinoma underwent partial or total gastrectomy. In samples from each carcinoma, gastrin peptides were characterized, using a library of sequence-specific immunoassays. Expression was also demonstrated by immunohistochemistry. In addition, the gastrin and gastrin/CCK-B receptor gene expression was quantitated using real-time PCR, and the receptor protein demonstrated by western blotting.. α-Amidated gastrins were detectable in 16 of 20 carcinomas (median concentration 2.1 pmol/g tissue; range 0-386 pmol/g tissue). The tissue concentrations correlated closely to the gastrin mRNA contents (r = 0.75, p < 0.0001). Moreover, progastrin and non-amidated processing intermediates, including glycine-extended gastrins, were detected in 19 carcinomas. Immunohistochemistry corroborated gastrin expression in carcinoma cells. Chromatography revealed extensive progastrin processing with α-amidated gastrin-34 and -17 (tyrosyl-sulfated as well as non-sulfated) as major products. Finally, gastrin/CCK-B receptor mRNA and protein were detected in all tumors.. The results show that the elements for a local loop of α-amidated gastrins and their receptor are detectable in 80% of human gastric adenocarcinomas. Therefore, the results support the contention that locally expressed gastrin may be involved in the tumorigenesis of gastric adenocarcinomas.

Topics: Adenocarcinoma; Adult; Aged; Aged, 80 and over; Female; Gastrins; Gene Expression; Humans; Male; Middle Aged; Protein Precursors; Receptor, Cholecystokinin B; RNA, Messenger; Stomach Neoplasms

The gastrin gene is expressed widely in pancreatic adenocarcinomas and the study aimed to assess its role in both the resistance of cancer cells to apoptosis and the sensitivity of cells to chemotherapeutic agents. Two human pancreatic cell lines, PAN1 and BXPC3, expressed gastrin at both the RNA and protein levels and are shown to be representative of human pancreatic adenocarcinomas in terms of gastrin expression. Inhibition of endogenous gastrin production by tumor cells was achieved with neutralizing gastrin antiserum and transfection with a gastrin antisense plasmid. Gastrin antiserum synergized with both taxotere and gemcitabine in inhibiting the in vitro growth of the PAN1 cell line with the inhibitory effect of the antiserum increasing from 12.7% to 70.2% with taxotere (P < 0.05) and 28.6% with gemcitabine (P < 0.01) after controlling for the effects of the cytotoxics. Synergy was only achieved with taxotere in BXPC3 cells with the inhibitory effect of gastrin antiserum increasing from 22.9% to 50.0% (P < 0.005). Cells transfected with gastrin antisense had reduced in vitro growth in low serum conditions and were poorly tumorigenic in nude mice at an orthotopic site. Gastrin antisense-transfected PAN1 cells had increased sensitivity to the antiproliferative effects of both gemcitabine (IC50 of > 100 microg/ml reduced to 0.1 microg/ml) and taxotere (IC50 of 20 microg/ml reduced to < 0.01 microg/ml) when compared with vector controls. The increased sensitivity of PAN1 antisense coincided with increased caspase-3 activity and reduced protein kinase B/Akt phosphorylation in response to both gemcitabine and taxotere. Gastrin gene circumvention may be an optimal adjunct to chemotherapeutic agents, such as taxotere and gemcitabine, in pancreatic adenocarcinoma.

Topics: Adenocarcinoma; Animals; Antineoplastic Agents; Apoptosis; Cell Line, Tumor; Deoxycytidine; DNA, Antisense; Docetaxel; Gastrins; Gemcitabine; Gene Expression; Genetic Therapy; Humans; Male; Mice; Mice, Nude; Pancreatic Neoplasms; Phosphorylation; Protein Precursors; Protein Serine-Threonine Kinases; Proto-Oncogene Proteins; Proto-Oncogene Proteins c-akt; Taxoids; Transfection

A stepwise progression through premalignant stages has been identified for the intestinal type of gastric carcinoma. As gastrin has been identified as a growth factor for the intestinal type of gastric adenocarcinoma, the aim of this study was to investigate whether gastrin is expressed in premalignant gastric conditions.. Ninety archival samples of atrophic gastritis, intestinal metaplasia, mild gastric epithelial dysplasia, moderate gastric epithelial dysplasia, severe gastric epithelial dysplasia and intestinal-type gastric adenocarcinoma were obtained. Immunocytochemistry was performed using antibodies directed against gastrin and its post-translational precursors, and the gastrin/cholecystokinin B receptor. Positive staining was identified using the avidin--biotin immunoperoxidase method and quantified using an image analysis system.. Gastrin and its receptor were shown to be expressed in specimens of atrophic gastritis, intestinal metaplasia, epithelial dysplasia and the intestinal type of gastric carcinoma.. Gastrin seems to be an important growth factor in gastric carcinogenesis.

Topics: Adenocarcinoma; Biomarkers, Tumor; Gastrins; Humans; Immunohistochemistry; Protein Precursors; Pyloric Antrum; Receptor, Cholecystokinin B; Receptors, Cholecystokinin; Stomach Neoplasms

Progastrin-releasing peptide (proGRP) is a specific tumor marker in patients with small cell lung carcinoma (SCLC). It has been reported that serum proGRP levels rarely are elevated in patients with nonsmall cell lung carcinoma (NSCLC); the reported frequency is <3%. The purpose of this study was to examine the clinicopathologic features of NSCLC patients with high serum proGRP levels.. The authors measured serum proGRP levels with a TND-4 kit, a newly developed enzyme-linked immunoadsorbent assay, in 544 NSCLC and 206 SCLC patients. Pathologic features were examined using conventional hematoxylin and eosin staining and histochemical and immunohistochemical staining using polyclonal antibodies to proGRP, chromogranin A, calcitonin, and monoclonal antibody to the neural cell adhesion molecule (NCC-Lu-243).. The serum proGRP levels were elevated in 140 SCLC patients (68.0%) and in 23 NSCLC patients (4.2%). Seven of these 23 NSCLC patients had serum proGRP levels > or = 100 pg/mL. They included two patients with renal dysfunction, one patient diagnosed cytologically with adenocarcinoma without undergoing precise pathologic examination, two patients diagnosed histologically with squamous cell carcinoma with foci of small cell elements, and two patients diagnosed with large cell neuroendocrine carcinoma and poorly differentiated adenocarcinoma, respectively, which showed neuroendocrine differentiation on immunohistologic analysis. The remaining 16 NSCLC patients had serum proGRP levels < 70 pg/mL.. Nearly all NSCLC patients had serum proGRP levels < 100 pg/mL. However, if an NSCLC patient presents with a proGRP level > or = 100 pg/mL, the clinicopathologic features must be examined with regard to the small cell component, neuroendocrine differentiation, and renal dysfunction.

Topics: Adenocarcinoma; Adult; Aged; Biomarkers, Tumor; Carcinoma, Large Cell; Carcinoma, Non-Small-Cell Lung; Carcinoma, Squamous Cell; Enzyme-Linked Immunosorbent Assay; Female; Gastrins; Humans; Lung Neoplasms; Male; Middle Aged; Protein Precursors; Renal Insufficiency

To evaluate the hypothesis that gastrin is a local growth factor in colonic carcinomas, the expression of gastrin messenger RNA (mRNA) and peptides were examined in five human colon carcinoma cell lines, 12 solid colon carcinomas, and normal colonic tissue.. Northern analysis, reverse-transcription PCR, and a library of sequence-specific radioimmunoassays were the principal methods.. Cell lines, tumors, and normal tissue all expressed a gastrin mRNA of 0.7 kilobases, and all cell lines contained incompletely processed progastrin (range, 17-54 fmol/10(6) cells). Two cell lines secreted progastrin into the media (LoVo, 25 +/- 3 pmol/L; HCT116; 12 +/- 2 pmol/L). Normal colonic tissue and all the solid tumors also contained progastrin, the concentration being higher in tumors (range, 0.4-2 pmol/g) than in normal tissue (range, 0.1-0.2 pmol/g). Only one tumor contained carboxyamidated gastrins.. Normal and neoplastic colonic mucosa both express the gastrin gene, but the posttranslational phase of expression is attenuated. The incomplete processing and low level of expression suggest that autocrine gastrin secretion has only minor significance for normal adult and most neoplastic colonic tissue.

Topics: Actins; Adenocarcinoma; Blotting, Northern; Colon; Colonic Neoplasms; Colorectal Neoplasms; Exons; Gastric Mucosa; Gastrins; Humans; Oligodeoxyribonucleotides; Polymerase Chain Reaction; Protein Precursors; Rectal Neoplasms; RNA Probes; RNA, Messenger; Tumor Cells, Cultured

Processing-independent radioimmunoanalysis for progastrin showed that extracts of normal pancreatic tissue from normal subjects (n = 5) and from patients with adenocarcinoma of the papilla of Vater (n = 4) contain progastrin and its products. The concentrations varied from 0.1 to 5.8 pmol/g tissue, of which carboxyamidated bioactive gastrins constituted 0.03-1.9 pmol/g. In histologically normal and nonneoplastic pancreatic tissue from patients with duodenal (n = 3) and pancreatic (n = 2) gastrinomas the expression of gastrin was significantly higher-14.5 pmol/g (median), of which 28% was bioactive amidated gastrins. Gastrin-17 was the main bioactive product, but its immediate precursor, glycine-extended gastrin-17, constituted the predominant part of the preprogastrin product in pancreatic tissue. Proper gastrinoma tissue contained several precursor forms, including intact unprocessed progastrin. Progastrins were also found in high concentrations in plasma from the gastrinoma patients. The results raise the possibility that increased expression of progastrin and its products in non-neoplastic pancreatic tissue is a primary defect predisposing to neoplasia.

Topics: Adenocarcinoma; Ampulla of Vater; Common Bile Duct Neoplasms; Gastrinoma; Gastrins; Gene Expression; Humans; Pancreas; Pancreatic Neoplasms; Protein Precursors; Protein Processing, Post-Translational; Zollinger-Ellison Syndrome

Topics: Adenocarcinoma; Adult; Aged; Female; Gastric Mucosa; Gastrins; Gastrointestinal Diseases; Humans; Male; Middle Aged; Peptic Ulcer; Peptide Fragments; Protein Precursors; Pyloric Antrum; Stomach Neoplasms