AR and prostate cancer: The most frequent genetic alterations occurring in mCRPCs occur at the level of AR, ETS (ETS fusions), TP53, and PTEN; both AR and GNAS are mutated exclusively in mCRPC; TP53 alterations are much more frequent in mCRPC than in primary cancers; there are no gene alterations exclusively observed in primary prostate cancers (Figure 2) [67].