The effect of testosterone on chemical carcinogenesis in the buccal pouches of castrated and intact male hamsters.

Abstract

Tumors were induced in the cheek pouches of intact and castrated male Syrian golden hamsters by repeated topical application of 9,10-dimethyl-1,2-benzanthracene (DMBA). Half of the animals received in addition intramuscular injections of testosterone propionate throughout the treatment with DMBA. After 9 and 12 weeks of treatment, squamous cell carcinomas were reduced in number among intact animals receiving DMBA combined with testosterone. Among castrated animals treated with DMBA and testosterone, there were less tumors after 9 weeks than in castrated animals treated with DMBA only, but not after 12 weeks. The tumor incidence in intact and castrated animals treated with DMBA only was similar throughout the experiment. Thus in the present model testosterone appeared to decrease carcinoma formation in intact male animals.