Despite the well-recognized stage migration that has led to an improvement in prostate cancer outcomes since the era of prostate specific antigen (PSA)-based prostate cancer screening began, patients with high-grade prostate cancer remain at significant risk of morbidity and mortality.[1] Patients with Gleason score >8 cancer are often treated with radical prostatectomy or radiotherapy combined with adjuvant androgen blockade. Here, KLK3 is linked to prostate cancer.