In the TMPRSS2:ETV4 fusion event, a short regulatory region 8 Kb upstream of TMPRSS2 and containing an androgen-regulated enhancer is juxtaposed to an intronic region immediately upstream of exon 3 of ETV4. This fusion gene has not been reported in prostate cancer cell lines, but native ETV4 expression is present in RWPE, PC-3 and DU145 cells and its downregulation inhibits proliferation, anchorage-independent growth and migration of prostate cancer cells (Pellecchia et al., 2012). Here, TMPRSS2 is linked to prostate cancer.