AR and Familial prostate cancer: In summary, our present study shows that the nuclear receptor ERRα could perform a supportive role in the intratumoral androgen biosynthesis in prostate cancer via its direct transactivation of at least two key steroidogenic enzyme genes CYP11A1 and AKR1C3, and through this regulation it could help to promote the advanced growth of CRPC by activation of AR signaling (Figure 8E).