[The relationship between sexual maturation and growth of the subcutaneous sarcoma-180 tumor]

The sex hormones of mice have effects on the immune response and the synthesis of epidermal growth factor(EGF). Androgen inhibits the former and enhances the later, whereas estrogen has the opposite effect. EGF is one of the tumor growth factors. In the present study, mice before or after sexual maturation, or gonadectomized adults of both sexes, were subcutaneously inoculated with sarcoma-180 tumor cells. The tumors grew rapidly, with no difference in genders before sexual maturation. However, tumor growth was rapid in adult male mice after sexual maturation, but retarded or inhibited in adult female mice. In orchidectomized male mice, tumor growth slowed down, in ovariectomized female mice, tumor growth accelerated. There was no difference in the rate of tumor growth among gonadectomized mice of either sex.