This in turn inhibits the growth of cancer cells [56] by stimulating on the one hand the expression of cyclin-dependent kinase inhibitor p21, and therefore, inhibiting cell proliferation, while on the other hand, this activity is responsible for inducing cell differentiation [64], reducing aromatase activity and circulating levels of estrogens and therefore breast cancer risk. This evidence concerns the gene CYP19A1 and breast carcinoma.