Mechanism of ovarian carcinogenesis: effect of 7,12-dimethylbenz[a]anthracene administration on intrasplenic ovarian grafts in unilaterally ovariectomized C3HeB/Fe mice.

A single oral administration of 7,12-dimethylbenz[a]anthracene (DMBA) 2 weeks after intrasplenic grafting of ovarian tissue in unilaterally ovariectomized C3HeB/Fe mice resulted in a high tumor incidence (47%) in the grafted tissue, with only 1 tumor (3%) in the orthotopic ovary. No tumors were seen in the control group (unilaterally ovariectomized mice given intrasplenic grafts of ovarian tissue without subsequent DMBA administration), nor did tumors develop in response to DMBA treatment in mice with both ovaries in situ and no grafted tissue in the spleen. The results indicated that some local change caused by the grafting procedure rendered the tissues more sensitive to the action of DMBA and/or more responsive to gonadotropic stimulation.