Early lesions induced by DHPN in Syrian golden hamsters: influence of concomitant Opisthorchis infestation, dehydroepiandrosterone or butylated hydroxyanisole administration.

The effects of concomitant Opisthorchis infestation and dehydroepiandrosterone (DHEA) or butylated hydroxyanisole (BHA) administration on dihydroxy-di-n-propylnitrosamine (DHPN) induction of preneoplastic lesions were investigated in Syrian golden hamsters. Whereas parasite infection was primarily associated with first-order ductular proliferation in the liver and a secondary appearance of cholangiofibrotic lesions, DHEA treatment brought about increased carcinogen toxicity and enhanced generation of glutathione-S-transferase P (GST-P)-positive hepatocellular foci, liver cysts and focal proliferative changes in the pancreas. BHA also exerted an enhancing influence on pancreatic but not liver carcinogenesis. The results suggest that whereas alteration of DHPN metabolism by DHEA and BHA treatment effected changes at the initiation level, opisthorchiasis principally exerted an enhancing influence subsequent to carcinogen withdrawal.