Specifically, the mammary tumor effect of hyperinsulinemia was demonstrated in females of the transgenic MKR mouse model of T2D, inoculated with the mammary cancer cell lines, Met1 (7) and Mvt1 (8), where tumors derived from both cell lines showed a significant increase in growth rate in MKR females compared with wild-type mice. The gene discussed is GZMM; the disease is breast cancer.