TMPRSS2 and prostate intraepithelial neoplasia: Chinnayian's group has identified androgen regulated prostate-specific serine protease (TMPRSS2) and ERG gene fusions, TMPRSS2-ERG, as the predominant molecular subtype of prostate cancer and demonstrated that TMPRSS2-ERG fusions help in distinguishing between PIN and prostate cancer [24-26].