INS and endometrial cancer: 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.