In almost half of patients with prostate cancer, the tumor carries one of recurrent translocations that place one of the genes from the ETS family (ERG, ETV1, ETV4, ETV5, FLI1) downstream to the promoter of a gene active in the prostate, with consequent aberrant overexpression of the respective ETS gene [2–5]. This evidence concerns the gene ETV4 and prostate cancer.