In our previous study, we analyzed the prognostic value of the baseline serum hormones in patients with metastatic castration-resistant prostate cancer (mCRPC) treated with abiraterone, we found that higher serum PRL was a poor prognostic factor for patients with mCRPC, and higher expression of PRL was found in CRPC tissues compared to hormone naive prostate cancer (HNPC) and begin prostate hyperplasia (BPH) tissues. This evidence concerns the gene PRL and benign prostatic hyperplasia.