Mitochondrial reactive oxygen species (ROS) increased with metformin and PEITC treatment. A. Live cell confocal image of SKOV3 cells treated for 24 hours. MitoSOX, a mitochondrial specific superoxide detector, exhibits increased fluorescence in metformin and PEITC treated cells comparison to control treated cells. B. Mean fluorescence intensity from dihydroethidium (DHE) used to detect total cellular ROS. Cell lines were treated for 24 hours with or without metformin [8 mM] and DHE intensity was measured by flow cytometry.