Abstract: Type 2 diabetes drug metformin could inhibit proliferation, migration, epithelial mesenchymal transformation, aerobic glycolysis, angiogenesis and promote apoptosis through regulating multiple miRNAs in malignant tumors such as pancreatic cancer, cholangiocarcinoma, prostate cancer, ovarian cancer, breast cancer, endometrial cancer, oral cancer, stomach cancer and lung cancer. Further exploring the key miRNAs regulated by metformin, will help clarifying the underlying mechanism of metformin’s tumor inhibition effect and developing new therapies for treating cancer.

Key words: metformin, miRNA, malignant tumors, mechanism