Protective effect of dehydroepiandrosterone against aflatoxin B1-and 7,12-dimethylbenz(a)anthracene-induced cytotoxicity and transformation in cultured cells.

Dehydroepiandrosterone, an adrenal steroid that has been reported to be produced in subnormal amounts and found in lower plasma concentrations in women with benign and malignant breast tumors, protects cultured rat liver epithelial-like cells against aflatoxin B1-induced cytotoxicity and protects hamster embryonic fibroblasts against aflatoxin B1- and 7,12-dimethylbenz(a)anthracene-induced transformation. Related androgenic steroids show significantly less protective effect. Dehydroepiandrosterone also inhibits the rate of conversion of [3H]-7,12-dimethylbenz(a)anthracene to water-soluble metabolites by rat liver epithelial-like cells, suggesting that the steroid probably exerts its protective effect by inhibiting carcinogen activation.