Currently, screening for prostate cancer begins with a test that measures the amount of prostate-specific antigen (PSA); however, PSA usefulness in prostate cancer screening has been widely argued since an elevated PSA level may be caused by prostate cancer but can also by other conditions, including an enlarged prostate (benign prostatic hyperplasia) and inflammation of the prostate (prostatitis), which may cause “false-positive” results [3]. Here, KLK3 is linked to male reproductive organ cancer.