Study on the estrogen production in parenchymatous cells of epithelial ovarian tumor

From among tumors occurring in the ovaries, tumors originating in the gonadal stroma referred to as hormone-producing tumors produce estrogen (E). However, these were previously not considered to be hormone-producing tumors. Enzymatic histochemical and enzymatic electron microscopic studies were conducted to determine the presence of key enzyme of steroid biosynthesis as well as E precursors in epithelial cells for the purpose of identifying estrogen-producing cells in the epithelial cells of ovarian tumors. Moreover, a study was also conducted regarding the relationship of such cells with sex hormone receptors. The key enzyme of estrogen biosynthesis (3 beta-hydroxysteroid dehydrogenase) has been clearly verified in epithelial cells of ovarian tumors, having been demonstrated in electron microscopic studies to exist locally in the inner membrane of mitochondria. In addition, it has also been verified that this enzyme co-exists with estrogen precursors, suggesting the possibility that an estrogen-producing mechanism exists in ovarian tumor epithelial cells. As this key enzyme has also been verified in the same cells of both estrogen receptors (ER) and progesterone receptors (PR), this suggests the possibility that an autocrine system related to some type of function like that of a secretory function exists in tumor cells.