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Query: UNIPROT:P01350 (gastrin)
 9,683 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The effect of enprostil and the somatostatin analogue SMS 201 995 on the growth of a clonal variant of the human gastric adenocarcinoma cell line, MKN45, was studied. The derived cell line grew twice as fast as MKN45 when grown as a xenograft line in nude mice. However, it did not respond trophically to gastrin either in vitro or in vivo (unlike MKN45) although it possessed the same number of gastrin receptors as the parental line. Gastrin production by the cell line during in vitro culture was twice that of MKN45; thus, the cell line was denoted MKN45G. When MKN45G was grown as xenografts in nude mice (n = 10/group), enprostil (20 micrograms/kg/day) significantly inhibited tumour growth when administered continuously by an osmotic mini-pump from day 1 to day 7 of a 20-day experiment, and induced tumour regression when administered from day 7 to day 14. Enprostil reduced postprandial serum gastrin levels when administered from day 7 to day 14 and prevented gastrin release by MKN45 in vitro. SMS 201 995 at doses of 25 and 240 micrograms/kg/day induced tumour regression when administered from day 1 to day 7 and the former dose reduced post-prandial serum gastrin levels at day 5. Gastrin release by MKN45G was not affected by SMS 201 995 in vitro, thus its effect may not be mediated directly via gastrin, requiring interaction between other hormones or growth factors in the in vivo situation.
Int J Cancer 1990 Jan 15
PMID:The effect of the E2 prostaglandin enprostil, and the somatostatin analogue SMS 201 995, on the growth of a human gastric cell line, MKN45G. 210 79

Pulmonary blastoma is an infrequent malignant neoplasm, so called because of its resemblance to fetal lung. The original description outlined the components as variable mixtures of epithelial and stromal elements. More recently, a variant displaying almost exclusively epithelial differentiation has been described. We report our findings in a case of pulmonary blastoma with predominance of epithelial cells, forming tubular structures and large morules. The architectural arrangement of the morules was remarkably similar to normal bronchial neuroepithelial bodies. Moreover, their immunohistochemical profiles were also very similar, including the expression of cytokeratins, chromogranin, neuron-specific enolase, synaptophysin, gastrin, calcitonin, bombesin, somatostatin and serotonin.
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PMID:Pulmonary blastoma with neuroendocrine differentiation in cell morules resembling neuroepithelial bodies. 212 6

Gastrin releasing peptide (GRP) is a 27 amino acid hormone that elicits a variety of biological effects. Receptor-binding antagonists of GRP may have therapeutic use in several pathologic conditions including cancer. The identification and characterization of GRP receptor antagonists have been aided by the use of murine 3T3 cells that possess functional GRP receptors. However, no human or primate cell lines that possess high-density GRP receptors and exhibit a biochemical or biological response to GRP have been described. To address this problem, we examined a series of cell lines and found that GRP specifically binds to Cos-7 monkey cells and stimulates elevation of intracellular calcium in these cells. Cos-7 cells exhibit a single class of high-affinity (dissociation constant = 0.13 nM) GRP binding sites (35,000/cell). Cross-linking experiments that use radiolabeled GRP identified two species of putative GRP receptor proteins (relative molecular mass, 90,000 and 22,000). Competitive binding inhibition studies indicate that Cos-7 cells tightly bind GRP-specific receptor antagonists. These antagonists block the binding of radiolabeled GRP to Cos-7 cells and inhibit GRP-stimulated elevation of intracellular calcium. These properties make Cos-7 cells a useful reagent for the study of GRP receptor antagonists.
J Natl Cancer Inst 1990 Mar 07
PMID:High-density functional gastrin releasing peptide receptors on primate cells. 215 85

Multi-autocrine loops of the epidermal growth factor (EGF), transforming growth factor alpha (TGF alpha), platelet-derived growth factor (PDGF) and TGF beta system are expressed in human gastrointestinal carcinomas. In esophageal and gastric carcinomas, they evidently play an important role in tumor progression. Gastrin, one of the major gut hormones, may also act as an autocrine growth factor for gastric and colonic carcinomas. The HST1 and INT-2 genes, belonging to the fibroblast growth factor gene family, are coamplified in approximately 50% of primary tumors and in all the metastatic tumors of esophageal carcinoma. TGF alpha and EGF are the ligands of the tumor cells that overexpress EGF receptor in esophageal carcinomas. The synchronous expression of EGF and its receptor, as well as TGF alpha and ras p21, is evidently correlated with the depth of tumor invasion, metastasis and prognosis of gastric carcinomas. Amplification of c-erbB-2 and EGF receptor genes has been observed in many metastatic sites of gastric carcinomas regardless of histological type. In addition to TGF alpha and EGF, TGF beta and PDGF A chain produced by tumor cells may stimulate collagen synthesis not only by fibroblasts but also by tumor cells themselves, resulting in extensive progression and diffuse fibrosis of scirrhous gastric carcinomas. Moreover, TGF alpha or EGF and estrogen may also play a cooperative role in the development of scirrhous gastric carcinoma. In colorectal carcinoma, it has been shown that the accumulation of several alterations in ras genes and p53 genes is most important for the conversion of adenoma to carcinoma. Critical genetic changes, including activation of oncogenes, mutation and deletion of tumor suppressor genes and disturbances in transcriptional regulatory sequences, may bring about aberrant expression of growth factors and their receptors in gastrointestinal carcinomas. The understanding of the significance of EGF-related growth factors in tumor progression provides a framework for a biological approach to the therapy of human gastrointestinal carcinomas. 8-Cl-cAMP, which inhibits expression of oncogenes and TGF alpha, may be useful not only for cancer therapy but also for the study of cell differentiation.
J Cancer Res Clin Oncol 1990
PMID:Growth factors and oncogenes in human gastrointestinal carcinomas. 215 13

We report the establishment and characterization of four continuous cell lines derived from human primary and metastatic gastric carcinomas, and we compare their properties with a panel of colorectal carcinoma cell lines previously established and reported by us. Our success rate in culturing gastric carcinomas was relatively low, especially from primary tumors, compared to colorectal carcinoma. These observations may reflect the relatively modest number of gastric carcinoma cell lines established (mainly from Japan), compared to the abundance of colorectal carcinoma lines established worldwide. All four gastric lines expressed the surface glycoproteins carcinoembryonic antigen and TAG-72 and three lines expressed CA 19-9. Two of the lines expressed aromatic amino acid decarboxylase but lacked other markers for neuroendocrine differentiation. All four lines were positive for vasoactive intestinal peptide receptors but lacked gastrin receptors. In addition, two lines expressed receptors for muscarinic/cholinergic receptors but not beta-adrenergic receptors. Cytogenetic evidence for gene amplification was present in the cell lines. All four lines contained varying numbers of double-minute chromosomes. One line, SNU-16, was amplified for the c-myc proto-oncogene and contained four homogeneously staining regions. While c-myc and c-erb-B-2 RNA were expressed by all lines, there was no evidence of amplification or overexpression of several other proto-oncogenes and growth factors. The multiple properties we have described in our gastric carcinoma cell lines are remarkably similar to those found in the panel of colorectal carcinoma cell lines. These properties include morphology, growth characteristics, expression of surface glycoproteins, partial expression of neuroendocrine cell markers, frequent chromosomal evidence of gene amplification, and occasional amplification of the c-myc proto-oncogene. Our four well characterized cell lines should provide useful additions to the modest number currently available for in vitro studies of gastric carcinoma.
Cancer Res 1990 May 01
PMID:Characteristics of cell lines established from human gastric carcinoma. 215 97

A biologically active, chemically defined, radioactive ligand was used for characterizing bombesin (BBS) receptors on rat pancreatic acinar cancer cells (AR42J). [Tyr4]BBS, iodinated with enzymobeads and fractionated by high-performance liquid chromatography, was monitored for biological activity as evidenced by gastrin release from perfused isolated rat stomach. The monoiodinated peptide peak was greater than 95% biologically active, with a specific activity of greater than 2,000 disintegrations.min-1.fmol-1. The maximum number of BBS receptors per cell were measured at 30 degrees C after 20-25 min of incubation; binding was submaximum at temperatures lower or higher than 30 degrees C. A single class of high-affinity binding sites (Kd = 1.77 +/- 0.21 nM) was identified for BBS on AR42J cells and nonspecific binding was less than 20-30% at all points. A total of 1.47 +/- 0.14 x 10(5) specific BBS binding sites per cell were measured that were specific for BBS and gastrin-releasing peptide (GRP) analogues. Iodinated GRP-(1-27) was cross-linked to BBS receptors on AR42J cells using several bifunctional cross-linking reagents followed by polyacrylamide gel electrophoresis of the solubilized receptor complex under reducing and nonreducing conditions. A densitometric analysis of the autoradiographs demonstrated the presence of an approximately 80- to 85-kDa molecular form of the receptor as a major component under both reducing and nonreducing conditions. These results indicated that the receptor molecule is a single subunit without multiple chains covalently attached by disulfide bonding.
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PMID:Molecular characterization of bombesin receptors on rat pancreatic acinar AR42J cells. 215 42

Ten patients with hepatic metastases from islet cell tumors or carcinoid tumors had clinical symptoms from hormonal secretion and/or pain related to the mass effect of neoplastic liver involvement. Hepatic arterial embolization (HAE) using radiographically guided catheters to inject thrombogenic material was applied to the right and/or left hepatic arteries separately 5 to 7 days apart. All ten patients improved within days of the procedure as confirmed by a decrease in measurable hormone levels (gastrin, adrenocorticotropin, and 5-hydroxy indole acetic acid) or by a decrease in tumor size and improved symptoms. Three patients underwent repeated reembolization from two to four times over nine to 50-month intervals for symptom control. Complications of and indications for HAE in these patients are discussed. It appears to be an effective treatment for dealing with the hormonal syndromes and local symptoms related to the hepatic metastases of hormone-secreting tumors.
Cancer 1990 May 15
PMID:Hepatic arterial embolization for metastatic hormone-secreting tumors. Technique, effectiveness, and complications. 216 Dec 78

Gastric cancer remains a disease with a very poor prognosis, and there is no safe and effective form of therapy for advanced disease. Evidence is now abundant to show that gastrin stimulates the growth of both gastric and colorectal cancer cells in vitro and in vivo, and that blockade of gastrin receptors can prolong survival in xenografted nude mice. We have thus performed a randomized, controlled study of the gastrin/cholecystokinin receptor antagonist proglumide as therapy in 110 patients with gastric carcinoma. Proglumide had no overall effect on survival (Mantel-Cox statistic = 0.5, P = 0.48). The 95% confidence interval for the proglumide treated group was 260 to 474 days compared to 230 to 372 days for the control group. No significant difference was seen with proglumide, which has a relatively low affinity with the gastrin receptor and also has partial agonist activity. Drugs that are far more specific and potent gastrin receptor antagonists are becoming available, which may have a greater effect on survival, and further clinical trials of such compounds are clearly indicated to determine the efficacy of hormonal control of gastrointestinal malignancy.
Cancer 1990 Oct 01
PMID:The effect of the gastrin receptor antagonist proglumide on survival in gastric carcinoma. 220 95

We report a case of multiple duodenal ulcers with gastric hypersecretion due to a nongastrin secretagogue produced by a malignant tumor of the pancreas in a 78-year-old man. The case resembled a Zollinger-Ellison syndrome (ZES) with high acid output (basal acid output 27, sham meal-stimulated 37, maximum acid output 47 mEq/h), but with fasting gastrin 43 pg/ml, nonresponsive to secretin. As in ZES, pepsin output was comparatively low, and secretion was inhibitable by atropine (50% inhibited by 1 microM). The tumor removed at surgery contained less than 1 ng gastrin per gram, but was many times more potent than pentagastrin in stimulating acid from a lumen-perfused rat stomach. The tumor also contained cholecystokinin (CCK-8 and CCK-33), motilin, insulin, and somatostatin, which were also present in adjacent normal pancreas; in addition, the tumor contained pancreatic polypeptide and pancreatic cancer-associated antigen. This case represents a rare syndrome due to an as yet undefined peptide secreted by a (frequently malignant) pancreatic endocrine tumor and masquerading as ZES. This is the first report of studies of pepsin secretion and of the effect of atropine, suggesting that the physiologic effects of the secretagogue resemble that of gastrin.
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PMID:A nongastrin malignant ampullary tumor causing gastric acid and pepsin hypersecretion. A case report. 223 2

Previous studies of the relationship between dietary fat and breast cancer have produced conflicting results and have provided no definitive evidence of a mechanistic link between fat and breast tumorigenesis. We conducted a study to compare postprandial levels of prolactin (Prl), a hormone suspected of promoting the growth of some human breast cancer, and several gut hormones, i.e., gastrin (Gs), vasoactive intestinal polypeptide (VIP), neurotensin (Nt), and cholecystokinin (CCK), following high- and low-fat isocaloric test meals. Data were obtained in the posttreatment period from 13 patients with breast cancer (nine stage I and four stage II), who were disease free clinically, and nine healthy controls. Subjects admitted to the research unit on 2 days were given the high-fat meal on day 1 and the low-fat meal on day 2. Blood samples were drawn before (i.e., fasting) and after test meal consumption. All hormone analyses were performed by radioimmunoassay. Results indicated a significant rise in postprandial Prl levels for stage II patients, but not for stage I patients or the controls. Postprandial Gs levels were also elevated, whereas VIP levels were markedly reduced in patients versus controls; these differences were most marked in stage II patients. No significant intergroup differences were noted in postprandial levels of Nt and CCK. Hormone levels of patients and controls did not differ between the test meal situations, which indicated that some other component of the test meals might have been responsible for altered Prl and Gs levels. The differences observed between the stage I and II patients indicated that diet may influence the aggressiveness of tumor behavior and development through alterations in postprandial hormone release.
J Natl Cancer Inst 1990 Jan 03
PMID:Postprandial levels of prolactin and gut hormones in breast cancer patients: association with stage of disease, but not dietary fat. 235 41


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