There are no studies regarding gene expression or epigenetic suppression of KLOTHO, although a number of genes – including Glutathion S-transferase PI (GSTP1) (Majumdar et al. 2011), Estrogen Receptor Alpha (ERα), Estrogen Receptor Beta (ERβ) (Sasaki et al.2002), Adenomatous polyposis coli (APC), RAS association domain family 1A (RASSF1A) (Liu et al.2011), Retinoic acid receptor beta 2 (RARB2) (Gao et al. 2013), and Prostaglandin-endoperoxide synthase 2 (PTGS2) (Bastian et al. 2007) – are hypermethylated in prostate cancer. Here, ESR2 is linked to prostate cancer.