Urinary prostate protein glycosylation profiling as a diagnostic biomarker for prostate cancer

BACKGROUND Serum prostate-specific antigen (sPSA) measurement is widely used as opportunistic screening tool for prostate cancer (PCa). sPSA suffers from considerable sensitivity and specificity problems, particularly in the diagnostic gray zone (sPSA 4–10 µg/L). Furthermore, sPSA is not able to discriminate between poorly-, moderately-, and well-differentiated PCa. We investigated prostatic protein glycosylation profiles as a potential PCa biomarker. METHODS Differences in total urine N-glycosylation profile of prostatic proteins were determined between healthy volunteers (n = 54), patients with benign prostate hyperplasia (BPH; n = 93) and newly diagnosed PCa patients (n = 74). Variations in N-glycosylation profile and prostate volume were combined into one urinary glycoprofile marker (UGM). Additionally, differences in N-glycosylation were identified between Gleason 7. RESULTS The UGM was able to discriminate BPH from PCa, overall and in the diagnostic gray zone (P 7 (P = 0.010 and P = 0.020, respectively) and between Gleason = 7 and Gleason > 7 (P = 0.011 and P = 0.025, respectively). CONCLUSIONS The UGM shows high potential as PCa biomarker, particularly in the diagnostic gray zone. Further research is needed to validate these findings. Prostate 75:314–322, 2015. © 2014 Wiley Periodicals, Inc.