Aim: Current prostate cancer (PCa) diagnostics are based on PSA level assessment as well as histological analysis of biopsies. However, both false negative and false positive diagnoses are still made. Sensitive and specific markers of PCa are needed. In the present manuscript 14 different cell-free miRNAs were studied in blood plasma extracellular vehicles (EVs) of PCa and benign prostatic hyperplasia (BPH) patients as well as healthy donors. Materials and Methods: Plasma EVs isolation was performed by an aggregation-precipitation protocol. miRNA was isolated by the guanidine isothiocyanate/octanoic acid protocol. miRNAs expression was assessed by reverse transcription and quantitative PCR. Results: It was shown, that the expression of 2 miRNA ratios: miR-30e/miR-19b and miR-19b/miR-92a, differed between all groups. 8 miRNA ratios differentiated PCa patients and healthy donors, 15 ratios differentiated BPH and PCa patients, as well as BPH patients and healthy donors. 12 miRNA pairs aberrantly expressed in blood EVs of PCa and BPH patients were characterized by ddCt values over 1,0. Moreover, three of these miRNA ratios (miR-378a/miR-30e, miR-378a/miR-144, and miR-660/miR-19b) were characterized by high values of AUC (79%–82%), sensitivity (70%–78%) and specificity (63%–81%). Conclusion: The diagnostic characteristics of studied miRNA ratios indicate that they cannot be considered an independent and sufficient diagnostic marker but, quite likely, can be used as additional indicators if a diagnosis is needed to be clarified. Their potential as additional markers to PSA is substantiated by the lack of significant correlation between these markers.
prostate cancer; miRNA; liquid biopsy; blood plasma; benign prostatic hyperplasia; extracellular vesicles