The utility of urine-circulating miRNAs for detection of prostate cancer

Background: In this paper, the utility of urine-circulating microRNAs (miRNAs) as the potential biomarker of prostate cancer (PCa), the second most prevalent male cancer worldwide, was evaluated. Methods: Cancerous (N = 56) and non-cancerous (N = 16) prostate tissues were analysed on TaqMan Low Density Array, with the initial screening of 754 miRNAs in a subset of the samples. The abundance of selected miRNAs was analysed in urine specimens from two independent cohorts of patients with PCa (N = 215 overall), benign prostatic hyperplasia (BPH; N = 23), and asymptomatic controls (ASC; N = 62) by means of quantitative reverse transcription PCR. Results: Over 100 miRNAs were found deregulated in PCa as compared with non-cancerous prostate tissue. After thorough validation, four miRNAs were selected for the analysis in urine specimens. The abundance of miR-148a and miR-375 in urine was identified as specific biomarkers of PCa in both cohorts. Combined analysis of urine-circulating miR-148a and miR-375 was highly sensitive and specific for PCa in both cohorts (AUC = 0.79 and 0.84) and strongly improved the diagnostic power of the PSA test (AUC = 0.85, cohort PCa1), including the grey diagnostic zone (AUC = 0.90). Conclusions: Quantitative measurement of urine-circulating miR-148a and miR-375 can serve as the non-invasive tool for sensitive and specific detection of PCa.