ERα-mediated estrogen signaling was shown to be crucial in the development of ovarian cancer, supported by the observation that ERα is frequently overexpressed in ovarian tumors, and that anti-estrogen treatments such as the application of tamoxifen or aromatase inhibitors improves survival in certain subtypes of ovarian cancer [2,16,17]. This evidence concerns the gene CYP19A1 and ovarian carcinoma.