AKR1C3 mRNA has been reported to be upregulated in metastatic and non-metastatic CRPC compared to local prostate carcinoma (4, 8, 9, 15) and the subsequent de novo synthesis of androgens in the prostate can drive androgen receptor (AR) activation and may be responsible for the development of resistance to androgen deprivation therapy in CRPC patients (6, 8, 16). The gene discussed is AR; the disease is prostate carcinoma.