In a study, quantitative reverse transcription-polymerase chain reaction (PCR) and pyrosequencing analyses of respective prostate cancer tissues and cell lines demonstrated that hypomethylation of retroelements might be associated with prostate cancer, generalized overexpression of HERV-K_22q11.23, and accessory Np9 transcript in some tumors; meanwhile, it was opposed to both DNA methylation in LTR and expression of HERV-K17 in cancerous tissues [97]. This evidence concerns the gene KRT17 and prostate cancer.