Comparative histochemical investigation of the glutathione S-transferase placental form and gamma-glutamyltranspeptidase during N-nitrosobis(2-hydroxypropyl)amine-induced pancreatic carcinogenesis in hamsters.

Immunohistochemical staining using anti-rat glutathione S-transferase placental form (GST-P) rabbit antibody and enzyme histochemical staining for gamma-glutamyltranspeptidase (gamma-GT) were investigated in putative preneoplastic lesions and adenocarcinomas in the pancreas of Syrian golden hamsters treated with N-nitrosobis(2-hydroxypropyl)amine (BHP). Areas with ductular proliferation, ductal hyperplasia, and intraductal carcinoma were strongly positive for GST-P binding and negative for gamma-GT. Cystic adenoma, microcarcinoma, and carcinomas were constantly positively stained by GST-P and partially positive for gamma-GT. GST-P appears to be useful as a positive marker for putative preneoplastic lesions in pancreatic carcinogenesis. Since normal acinar cells are strongly positive for gamma-GT, the findings might suggest that acinar cells contribute to the development of cystic adenoma, microcarcinoma, and carcinomas.