CAT and B-cell chronic lymphocytic leukemia: However, we did not find any positive association of SIRT3 overexpression with catalase or SOD2 levels in CLL cells obtained from previously untreated CLL patients (n = 10) (Supplementary Fig. S3); suggesting that SIRT3 mediated regulation of SOD2 or catalase gene transcription may be context-dependent and/or cell-type specific.