FMO5 and prostate carcinoma: This finding is consistent with the stimulating effect of H2O2 on NAD(P)H oxidases-mediated O2•− production reported in human SMC, endothelial and cancer cells [39–41], and is further supported by upregulation of several isoforms of NAD(P)H oxidases in prostate cancer cell lines and tumor tissues [4, 28].