Metformin Inhibits Migration and Invasion by Suppressing ROS Production and COX2 Expression in MDA-MB-231 Breast Cancer Cells.

Background: Several mechanisms of action have been proposed to explain the apparent antineoplastic functions of metformin, many of which are observed at high concentrations that may not be reflective of achievable tissue concentrations. We propose that metformin at low concentrations functions to inhibit ROS production and inflammatory signaling in breast cancer, thereby reducing metastasis.

Methods: Using the highly invasive MDA-MB-231 breast carcinoma model, we ascertained the impact of metformin on cell viability by DNA content analysis and fluorescent dye exclusion.