The Synergistic Effects of Metformin and Chemotherapy on Ovarian Cancer. a Synergistic effects of metformin combined with chemotherapy (carboplatin) at different concentrations and different combination protocols (concentration of metformin: 0.25 and 0.5 mM; concentration of carboplatin: 5, 10, and 50 μM). Met.: metformin; Chemo.: chemotherapy. b The effects of metformin alone (0.5 mM), chemotherapy (carboplatin, 50 μM) alone, or combined treatment assessed by the indicated antibodies in Western blot analysis. c MTT assays showed that cells cultured in a high-glucose medium (4500 mg/L) exhibited greater growth than those in control medium (1000 mg/L). Green squares represent cells cultured in high-glucose medium, and red solid circles represent those cultured in control medium (concentration of metformin: 0.25 and 0.5 mM; concentration of carboplatin: 10 and 50 μM).