title: Effects of gastrin on tumor growth and cyclic nucleotide metabolism in xenotransplantable human gastric and colonic carcinomas in nude mice.
abstract: This study deals with the growth effect of gastrin on two xenotransplantable human gastric carcinomas (SC-6-JCK, poorly differentiated adenocarcinoma; and St-15, mucinous adenocarcinoma) and on one colonic carcinoma (Co-3, well-differentiated adenocarcinoma). In SC-6-JCK, the treatment with s.c. injection of pentagastrin at a dose of 10 micrograms/mouse once daily for 25 days promoted the growth of the tumor transplanted in nude mice, but gastrin had no effect at all on St-15 and Co-3. In SC-6-JCK, the weight, size, and labeling index of [3H]thymidine of the tumor were significantly increased in comparison with those of the control (p less than 0.05). In SC-6-JCK, cyclic adenosine 3':5'-monophosphate (cAMP) in the tumor was increased by a single i.p. injection of pentagastrin at a dose of 20 micrograms/mouse in nude mice, but such an increase was not observed in St-15 and Co-3. Cyclic guanosine 3':5'-monophosphate in SC-6-JCK was slightly increased by gastrin treatment but was not affected in the other tumors. In SC-6-JCK, at 30 min after gastrin treatment when cAMP showed a maximum increase, the activity ratio of cAMP-dependent protein kinase in the tumor was also elevated. In vitro also, gastrin stimulated cAMP production and cAMP-dependent protein kinase activation. The data suggest that some human gastric carcinomas may have receptor for gastrin.
mesh_terms: D000230:Adenocarcinoma / Q000378:metabolism / Q000473:pathology*; D000328:Adult; D000818:Animals; D002455:Cell Division / Q000187:drug effects; D002460:Cell Line; D003110:Colonic Neoplasms / Q000378:metabolism / Q000473:pathology*; D000242:Cyclic AMP / Q000378:metabolism*; D006152:Cyclic GMP / Q000378:metabolism*; D005260:Female; D005755:Gastrins / Q000494:pharmacology*; D006801:Humans; D007700:Kinetics; D008297:Male; D051379:Mice; D008819:Mice, Nude; D008875:Middle Aged; D009368:Neoplasm Transplantation; D011494:Protein Kinases / Q000378:metabolism*; D013274:Stomach Neoplasms / Q000378:metabolism / Q000473:pathology*; D014183:Transplantation, Heterologous
chemical_list: D005755:Gastrins; D000242:Cyclic AMP; D011494:Protein Kinases; D006152:Cyclic GMP