For example, oral contraceptives, by providing exogenous progestins, promote endometrial shedding, thereby effectively reducing the risk of endometrial hyperplasia and endometrial cancer induced by chronic anovulation; anti-androgen therapies, by lowering circulating androgen levels, may reduce androgen-mediated pro-carcinogenic signaling; and insulin sensitizers (such as metformin) help improve insulin resistance and lower hyperinsulinemia, both of which are believed to be closely associated with the development of certain types of cancer. This evidence concerns the gene INS and hyperinsulinism.