Investigation of circulating levels of some microRNAs in patients with benign prostatic hyperplasia, chronic prostatitis and prostate cancer

Objective: In this study, the objective was to evaluate the diagnostic performance of some miRNAs, which were shown to have a diagnostic value for prostate cancer (PCa), and the effect of chronic prostatitis (CP) to diagnostic performance of microRNAs in distinguishing benign prostatic hyperplasia (BPH) and PCa. Materials and Methods: Serum levels of 12 microRNAs (miRNAs) including miR-375, -141-3p, -93-5p, -125b-5p, 30c-5p, -26b-5p, -221-3p, -222-3p, -223-3p, 181-a2-3p, -331-3p ve let-7c-5p were investigated in serums of patients with BPH, CP, and PCa. Measurements were performed using Agilent Aria MX qRT-PCR device and Qiagen kits by following the kit procedure. Results: In the analysis, serum levels of miR-375, -125b-5p, -30c-5p, -26b-5p, -223-3p and let-7c-5p were downregulated in PCa group compared with non-cancer group and area under the curve (AUC) values of these miRNAs in discriminating PCa group from non-cancer group were calculated as 0.781, 0.782, 0.762, 0.874, 0.817 and 0.845, respectively. AUC values in discriminating PCa group from BPH group increased to 0.938 for miR-223-3p, 0.926 for miR-26b-5p and 0.888 for let-7c-5p. AUC value of the combination of miR-375 and miR-26b-5p in discriminating PCa group from non-cancer group was 0.891, AUC value of these two miRNAs in discriminating PCa group from BPH group was 0.944. Discussion and Conclusion: In our study, 12 miRNAs were studied and 6 of these miRNAs were found to be significantly downregulated in PCa. These miRNAs were considered as biomarker candidates as these miRNAs, individually or combined, could be used to discriminate PCa and benign diseases of prostate. Furthermore, it was seen that miRNAs had a higher specificity and sensitivity in discriminating only BPH and PCa groups without including chronic prostatitis group in statistical analyse. Thus, it was demonstrated in this study that in discriminating benign conditions of prostate and prostate cancer, chronic prostatitis might be an important interference factor in the evaluation of diagnostic performance of miRNAs.