The analysis showed a significantly increased concentration of OPG in the serum of women with both serous and mucinous cancer compared to the concentration in the control group, which indicates disturbances in the process of extrinsic apoptosis occurring with the participation of OPG, depending on the histological type of ovarian cancer, and may also indicate the autocrine secretion of this receptor by cancer cells. The gene discussed is TNFRSF11B; the disease is cancer.