Progress on the relationship between metformin and breast cancer / 中国肿瘤临床

ABSTRACT

Diabetes mellitus increases the risk of breast cancer and affects the prognosis of breast cancer patients. Metformin, an anti-diabetic drug, decreases blood glucose level and has a role in suppressing various cancers. In addition, metformin has a unique in-hibitory effect on breast cancer, i.e., it can inhibit breast cancer cells in vivo and in vitro. Moreover, metformin exerts its anti-tumor ef-fect on epidermal growth factor receptor 2 (HER-2) positive and monoclonal antibody trastuzumab-resistant breast cancer cell lines, breast cancer stem cells, and triple negative breast cancer cells. Metformin can reduce the risk of the breast cancer in patients with dia-betes, lower histologic grade, and increase expression of estrogen and progesterone receptors. Furthermore, metformin has certain effect on neo-adjuvant chemotherapy for breast cancer. This review aims to clarify the mechanism of metformin in restraining breast cancer based on basic and clinical study results.