Although no previous evidence showed the regulation of SRD5A3 by epigenetic modifications in cancers, SRD5A2 methylation in the promoter region leading to low expression was indicative of better survival for castration-resistant prostate cancer patients after androgen deprivation therapy [41], indicating the regulation of 5-alpha-reductase isoforms by epigenetic modifications in prostate cancer. This evidence concerns the gene SRD5A3 and Familial prostate cancer.