Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P01350 (gastrin)
 9,683 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The mammalian gastrin-releasing-peptide (GRP) and its structural amphibian analogue, bombesin, are known to be trophic factors for the normal exocrine pancreas. This work investigates the possible role of GRP in the growth of an acinar pancreatic cancer transplanted to the rat and in primary tumor cell cultures. Moreover, this adenocarcinoma was tested for its content of specific bombesin/GRP receptors by using autoradiographic technics and in vitro binding assays with tumor cells. In Lewis rats bearing the pancreatic carcinoma transplanted s.c. in the scapular region, chronic administration of GRP at the dose 30 micrograms/kg/day for 15 successive days significantly increased the tumor volume, the final tumor weight, and amylase, protein, RNA and DNA contents. Autoradiographic studies showed that tumor tissue was GRP receptor positive with a high density. The biochemical characterization indicated that receptor positive tumor tissue had saturable and high affinity receptors with pharmacological specificity for GRP and its bioactive analogues. In primary tumor cell cultures, GRP increased the incorporation of [3H] thymidine in DNA in a dose- and time-dependent manner. There was a good correlation between the ability of GRP and its COOH terminal analogues to elicit DNA synthesis and their affinity for 125I-GRP binding sites. These results from in vivo and in vitro experiments demonstrated that GRP induces growth of pancreatic carcinoma by acting directly on specific membrane receptors present on the tumor cells.
Cancer Res 1992 Jul 01
PMID:Gastrin-releasing peptide: in vivo and in vitro growth effects on an acinar pancreatic carcinoma. 131 29

Gastrin releasing peptide (GRP), the human homologue of bombesin (BN), is an autocrine growth factor for small cell lung cancer (SCLC) cells. The synthetic octapeptides [D-cpa1-beta-Leu8-des-Met9]litorin (BIM 26182) and [D-Phe6-Leu13-CH2NH-Cpa14]bombesin(6-14)NH2 (BIM 26189) are potent GRP/BN antagonists of the proliferation of 3T3 and rat pancreas cells. The effect of these analogues on the proliferation of four SCLC cell lines (SCLC 6, SCLC 41, SCLC 75, SCLC 74R) was tested in vitro and in vivo. Two of these SCLC lines (SCLC 41M and SCLC 75) had receptors for BN/GRP and expressed the prepro-GRP mRNA. BIM 26182 and BIM 26189 inhibited [3H]thymidine incorporation into the DNA of SCLC 41 cells, stimulated [3H]thymidine incorporation in SCLC 6, and had no effect on the two other cell lines. The SCLC implanted s.c. in nude mice were treated with either BIM 26182 or BIM 26189. BIM 26182 and BIM 26189 injected at the doses of 50 micrograms twice a day (s.c.) around the tumor for 10 to 21 days delayed the growth of SCLC 41 and of SCLC 75. The maximal effect was observed during the treatment period, after which the tumors regrew, suggesting a cytostatic effect of these peptides. No inhibitory effect of the peptides on SCLC 74R or SCLC 6 growth was observed. These data suggest that GRP antagonists are able to inhibit the in vitro and in vivo growth of BN/GRP receptors-positive SCLC.
Cancer Res 1992 Sep 15
PMID:Antitumoral activity of bombesin analogues on small cell lung cancer xenografts: relationship with bombesin receptor expression. 132 85

Serial changes in serum gastrin level were detected by radioimmunoassay in 58 lung cancer patients before and after operation. In comparing these tests with those of 40 cases of noncancerous thoracic lesions and 151 normal adults, the serum gastrin from lung cancer patients is significantly higher than that of noncancerous thoracic lesions and normal individuals (P less than 0.01). The gastrin level is closely related to stage of cancer, size of primary tumor, presence of lymph node metastasis, and type of histological classification. The serum gastrin was found to decrease gradually after the removal of the tumor and to return to normal on the 14th postoperative day. Those patients whose serum gastrin level can return to normal on the 14th postoperative day will have a good prognosis; if not, their prognosis will be very poor. These results suggest that serum from patients with lung cancer contains a high concentration of gastrin that can help differentiate benign from malignant thoracic lesions and evaluate prognosis of patients with lung cancer. Therefore, the cause of high serum gastrin in patients with lung cancer is likely due to the gastrin-producing property of the lung cancer cells.
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PMID:Pre- and postoperative sequential study on the serum gastrin level in patients with lung cancer. 132 75

Gastrin has been postulated to be a physiological growth factor, but compelling in vitro evidence of this has been difficult to obtain. In the present study we investigated whether small cell lung carcinoma cell lines could provide a useful model system to study the effects of gastrin on signal transduction and cell proliferation in vitro. We found that the addition of gastrin to small cell lung cancer cells loaded with the fluorescent Ca2+ indicator fura 2-tetraacetoxymethylester causes a rapid and transient increase in the intracellular concentration of Ca2+ ([Ca2+]i) followed by homologous desensitization. The [Ca2+]i response was especially prominent in the small cell lung carcinoma cell line H510. In this cell line, gastrin I, gastrin II, cholecystokinin residues 26-33 (CCK-8), and unsulfated CCK-8 increased [Ca2+]i in a concentration-dependent fashion with half-maximum effects at 7, 2.5, 3, and 5 nM, respectively. The Ca(2+)-mobilizing effects of gastrin and CCK-8 were prevented by proglumide, benzotript, and the specific gastrin/CCKB receptor antagonist L365260. Gastrin stimulated the clonal growth of H510 cells in semisolid (agarose-containing) medium, increasing both the number and the size of the colonies. Gastrin and CCK agonists were equally effective in promoting clonal growth. The broad-spectrum neuropeptide antagonists [D-Arg1,D-Phe5,D-Trp7,9,Leu11] substance P and [Arg6,D-Trp7,9,MePhe8] substance P (6-11) markedly inhibited gastrin-stimulated Ca2+ mobilization and clonal growth. These results show that gastrin acts as a direct growth factor through gastrin/CCKB receptors and demonstrate, for the first time, that these peptides can stimulate the proliferation of cells outside the gastrointestinal tract.
Cancer Res 1992 Nov 01
PMID:Gastrin stimulates Ca2+ mobilization and clonal growth in small cell lung cancer cells. 132 22

Several bombesin-receptor antagonists are available that inhibit secretory and growth effects of bombesin, in vitro. In the present study, we examined the effects of a new class of bombesin receptor antagonists (modified GRP(15-27) peptides, with D-Pro26 and D-Ala24 moieties), on bombesin mediated effects, in vivo and in vitro. Of the 10 different compounds tested, BW-10 or 2258U89 ([de-NH2)Phe19,D-Ala24,D-Pro26 psi(CH2NH)Phe27]-GRP(19-27)) was most potent towards inhibiting bombesin binding to rat pancreatic acinar cancer cells with an ID50 of 0.5 nM. BW-10 (1 and 10 nM) significantly inhibited the gastrin response to 1 nM bombesin, from isolated rat stomach, in vitro, in a dose-dependent fashion. BW-10 (10-100 nmol/kg) was equally effective at significantly inhibiting bombesin evoked gastrin release in anesthetized rats, in vivo. [D-Phe6]Bombesin(6-13)-propylamide (BIM), a member of another class of antagonists, reported previously to be the most potent antagonist, in vitro, on the other hand, enhanced bombesin provoked gastrin release in rats. The antagonistic effects of BIM, in vivo, may thus be more selective. Intravenous infusion of BW-10 (10 nmol/kg/h) partially depressed gastrin and pancreatic polypeptide and completely abolished insulin released in response to bombesin, in conscious dogs. These results suggest that BW-10 functions as one of the most potent bombesin receptor antagonists, in vitro and in vivo, which could potentially be used as a therapeutic compound in treatment of some human diseases.
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PMID:A novel bombesin receptor antagonist (2258U89), potently inhibits bombesin evoked release of gastrointestinal hormones from rats and dogs, in vitro and in vivo. 133 39

This article describes studies with four peptides, epidermal growth factor (EGF), transforming growth factor alpha (TGF alpha), gastrin-releasing peptide/bombesin (GRP), and gastrin. The mitogenic and anti-secretory activities of EGF/TGF alpha appear to be mediated by a single class of high-affinity membrane receptors but may involve different signal transducing mechanisms. Biological activity of EGF resides in the N-terminal 42 amino acid fragment with the C-terminal undecapeptide determining binding affinity. A parenteral depot formulation of an EGF-related peptide or a small molecule agonist of the EGF receptor could have utility in treating various ulcerative disorders of the gut. Although antagonism of EGF (and thus TGF alpha) receptors and/or transducing mechanisms is frequently cited as a potential therapeutic approach to hyperproliferative diseases, blocking the action of TGF alpha, GRP, or gastrin with neutralizing antibodies or receptor antagonists did not influence the growth of a wide range of solid tumors in nude mice. These findings suggest that, unless tumor growth displays absolute dependency on one particular mitogen, antagonism of a specific growth factor is unlikely to have great effect in cancer therapy.
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PMID:Therapeutic potential of growth factors and their antagonists. 134 Oct 74

Fifty exocrine pancreatic adenocarcinomas and 57 benign tumors induced in Syrian hamsters by N-nitrosobis(2-oxopropyl)amine (BOP) were examined for the presence of argyrophil cells antiinsulin, -glucagon, -somatostatin, -pancreatic polypeptide (PP), -gastrin/CCK, -vasoactive intestinal polypeptide (VIP), and - neuron-specific enolase (NSE) reactive cells. Argyrophil - and antihormone-reactive cells were found in the normal pancreatic ducts and in the acini, as well as in hyperplastic and atypical ducts/ductules, tubular complexes, benign lesions, and in 80% of ductal adenocarcinomas. Insulin and antiNSE-reactive cells were the most common, followed in decreasing frequency by glucagon, somatostatin, and PP cells. Antigastrin-/CCK-and -VIP-reactive cells were found in two cases. Argyrophil cells were present in about 60% of the tumors with Grimelius staining and in 55% of those with Churukian-Schenk staining. Insulin cells were seen in ductal cancer that had grown into a lymph node and in the lymph node metastases of another cancer. A novel finding was the presence of argyrophil and insulin cells within the lumen of some malignant glandular structures. Coexistence of several peptide cells was found in 52% of the cancers. The presence of argyrophil and hormone-producing cells in induced pancreatic ductal/ductular lesions further strengthens the existence of a close developmental relationship between exocrine and endocrine cells of the pancreas.
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PMID:Immunohistochemical characterization of endocrine cells in experimental exocrine pancreatic cancer in the Syrian golden hamster. 135 11

The rat pancreatic cell line, AR42J possessed high-affinity gastrin and somatostatin receptors and its growth was stimulated by physiological gastrin-17 concentrations between 5 x 10(-11) mol/l and 10(-9) mol/l as measured by [75Se]selenomethionine uptake. The somatostatin analogue, octreotide (2 x 10(-7) to 2 x 10(-11) mol/l), reduced this stimulated growth. Gastrin-stimulated AR42J growth was also inhibited by proglumide (3 x 10(-4) mol/l) and lorglumide (3 x 10(-5) mol/l) at maximal G17 concentrations of 5 x 10(-11) and 10(-10) mol/l, respectively, and the analogues competed with [125I] gastrin-17 (5 x 10(-10) mol/l) for binding to gastrin receptors on AR42J (50% inhibitory concentrations, less than or equal to 10(-3) mol/l and 4 x 10(-6) mol/l, respectively. Octreotide reduced the basal growth of the human gastric cell line, MKN45G, (which is associated with intracellular gastrin immunoreactivity) in serum-free medium to 73% of control at a concentration of 2 x 10(-8) mol/l, which was reversed by gastrin-17 (10(-10) mol/l). Lorglumide (3 x 10(-5) mol/l) also reduced the basal growth to 30% of control, which was reversed to 78% by 10(-5) mol/l gastrin. Proglumide had no effect on the basal growth of MKN45G.
Eur J Cancer 1992
PMID:Inhibition of gastrin-stimulated growth of gastrointestinal tumour cells by octreotide and the gastrin/cholecystokinin receptor antagonists, proglumide and lorglumide. 135 50

Many reports have emphasized the role of gastrin as a growth factor for normal gastrointestinal mucosa and gastrointestinal cancers. Recent studies have pointed out that this peptide acts also as a growth factor for the pancreatic cancer cell line AR42J. This effect is mediated by gastrin [cholecystokinin (CCK)-B] receptors. In the present study, we investigated gastrin (CCK-B) receptor expression in the azaserine-induced rat pancreatic carcinoma DSL-6, comparing it to normal rat pancreas, and we also characterized CCK receptor subtypes in this tumor. The results showed that there is extensive gastrin binding to the DSL-6 pancreatic carcinoma. No evidence of specific gastrin binding to normal pancreas was found. Analysis of the ability of gastrin-17-I to inhibit 125I-gastrin-I binding demonstrated that gastrin bound to a single class of receptors with a Kd of 0.21 +/- 0.04 nM and a binding capacity of 184 +/- 29 fmol/mg protein. 125I-Gastrin-I binding was inhibited by the specific CCK-B receptor antagonist L365,260 approximately 40 times more effectively than by the specific CCK-A receptor antagonist L364,718. Analysis of the ability of cholecystokinin octapeptide (CCK-8) to inhibit 125I-Bolton-Hunter-CCK-8 binding revealed two CCK binding sites, i.e., a high affinity site and a low affinity site. The observed binding affinities of CCK-8 were then introduced into the computer analysis of the dose-inhibition curve of the ability of gastrin-17-I to inhibit binding of 125I-Bolton-Hunter-CCK-8, which was significantly better fit by a three-site model than by a two-site model. The three sites meet the criteria for CCK-B, high affinity CCK-A, and low affinity CCK-A receptors. The binding capacity of CCK-B receptors constitutes 34% of the total high affinity CCK binding sites. This study demonstrated that DSL-6 pancreatic carcinoma expresses three subtypes of CCK receptors. Gastrin (CCK-B) receptors, which were not detected in normal rat pancreas, constitute about one third of the total high affinity CCK receptors. We suggest that novel expression of gastrin (CCK-B) receptors may be generated by gene mutation or amplification during carcinogenesis and may play an important role in promoting tumor growth.
Cancer Res 1992 Dec 15
PMID:Novel expression of gastrin (cholecystokinin-B) receptors in azaserine-induced rat pancreatic carcinoma: receptor determination and characterization. 145 79

Increased basal serum gastrin level has been described in patients presenting with colorectal cancer. The aim of this work was to study the evolution of serum gastrin levels after cancer treatment. We measured basal serum gastrin levels before and 1 to 2 months after treatment in 15 patients (7 men, 8 women; mean age: 61.6 years). There were 3 malignant polyps, 4 Dukes A, 3 Dukes B, 4 Dukes C and 1 Dukes D colonic cancers. Treatment included 3 endoscopic polypectomies, 2 laser photodestructions, and 10 surgical resections, Mean basal gastrin level after treatment (49.07 +/- 12.65 mIU/l) was significantly lower (P less than 0.002) than before treatment (104.47 +/- 26.98 mIU/l). In the 2 patients treated by laser therapy, recurrences were associated with reincreasing serum gastrin levels. These results suggest an "autocrine" secretion of gastrin.
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PMID:[Serum gastrin levels in colorectal cancers. Evolution after treatment]. 152 91


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