29 In breast cancer MDA-MB-231 cells and MCF-7 cells, the protein level, mRNA level (Figures 4a and b, Supplementary Figure 1C and 1E), and the activity of SOD2 (Figure 4c, Supplementary Figure 1I) were all increased in response to OA treatment under hypoxic conditions. This evidence concerns the gene SOD2 and breast carcinoma.