In this study, we identified twelve potential protein biomarker candidates including KLK3, SORD, AGR2, SPON2, MDH2, ACAD8, TPP1, DES, HNRNPA2B1, ASRGL1, UCHL1 and FLNA as differentially abundant between tumor and benign tissues from two independent PCa cohorts, PCF and PCZA (Fig. 5). This evidence concerns the gene KLK3 and neoplasm.