Metformin Synergistically Enhances Cisplatin-Induced Cytotoxicity in Esophageal Squamous Cancer Cells under Glucose-Deprivation Conditions

Figure 1

Metformin induced enhanced cytotoxicity in ECA109 cells and augments DDP-induced cytotoxicity in glucose-deprivation medium. (a) Dose-survival curves of ECA109 cells treated with varying concentrations of metformin in high glucose medium or glucose-deprivation medium; (b) treatment of ECA109 cells with 1 mM or 2 mM metformin led to a slight protective effect against DDP-induced cytotoxicity in high glucose medium; (c) treatment of ECA109 cells in glucose-deprivation medium with 20 μM or 100 μM metformin showed a synergistic cytotoxic effect with DDP. (d) Effect of various concentration of metformin on the cytotoxicity of 1 μM DDP. The CCK-8 reading of each point was normalized to the reading of control cells maintained in high glucose and glucose-deprivation medium, respectively. indicates no significant difference, indicates , indicates , met is short for metformin, and DDP is short for cisplatin.

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