Despite recent progress in the identification of genetic and molecular alterations in prostate cancer (PCa), the routine prognostic risk assessment of PCa patients currently relies on traditional clinicopathological prognostic factors, including Gleason score, clinical tumor stage, and serum PSA level at the time of diagnosis, which are used for stratify the patients into the low-, intermediate-, or high-risk group [19]. Here, KLK3 is linked to prostate cancer.