ESR1 and breast cancer: 2015). This is the first study to find that the DIM plus DOC combination decreases MnSOD protein expression. We found that the expression of MnSOD decreased to a greater extent with the combination treatment than with DIM or DOC alone, which was associated with increased ROS. Highly invasive MDA-MB231 cells and HER2 positive Sk-BR-3 cells have elevated levels of MnSOD compared to ER + breast cancer cell lines (Kattan et al. 2008). Suppression of MnSOD expression with antisense RNA increased H2O2 and reduced proliferation and tumor growth (Kattan et al. 2008).