Liquid-Biopsy Glycan Score Biomarker Accurately Indicates and Stratifies Primary and Metastatic Prostate Cancers

Prostate cancer (PCa) is the most commonly diagnosed cancer in males. Early PCa usually shows no clinical symptoms and its primary diagnosis is currently guided by liquid-biopsy testing of serum prostate-specific antigen (PSA). This testing suffers from high false-positive and false-negative rates. Identifying new biomarkers for precise liquid-biopsy detection of PCa is, thus, an acute clinical request. Here, by using an advanced dual-functional aptamer assay, we quantified the extent of glycosylation of PSA circulating in cancer patients' serum, linked it to cancer-related breakage of PSA complexes with serum-circulating proteins, and proved its facility for stratification of primary and metastatic PCa. PSA's "Glycan Score" 100% accurately informed about PCa status in a 30-patient cohort, while serum PSA's concentration correctly classified only 53% of PCa patients and did not inform about their PCa status. The Glycan Score liquid-biopsy test thus has a huge potential for accurate diagnosis and staging of PCa, enabling mass-screening program progress and advanced PCa treatment monitoring.