GSTP1 and prostate cancer: Previous studies investigating DNA methylation patterns at select genomic loci in prostate cancer resulted in discoveries of epigenetic differences between prostate cancer tissue and benign-adjacent prostate in genes such as glutathione s-transferase 1 (GSTP1), Ras association domain family member 1 (RASSF1), and adenomatous polyposis coli (APC), among others [8–10].