1,2-Dimethylhydrazine carcinogenesis in neonatally androgenized CBA mice.

The aim of this study was to investigate the possible influence of exposure to steroid hormones early in life on the susceptibility of animals as adults to chemical carcinogens. CBA male and female mice received a single subcutaneous injection of 0.5 mg testosterone propionate (TP) in olive oil within 24 h after birth. At the age of 2 months, neonatally androgenized and control mice started receiving weekly subcutaneous injections of 1,2-dimethylhydrazine (DMH). By the end of the experiment, 90% of neonatally androgenized females treated with DMH developed uterine sarcoma against 9% in control females treated with DMH, this difference being attributed to the hyperoestrogenization of androgenized females. In neonatally androgenized males treated with DMH 79% developed pararenal sarcoma and 71% colon tumours versus 25 and 32% respectively of control males treated with DMH.