Circulating microRNAs as novel biomarkers in the diagnosis of prostate cancer: a systematic review and meta-analysis

The diagnostic value of circulating microRNAs (miRNAs) detection in prostate cancer (PC) patients is currently under debate. Thus, we performed this meta-analysis of published literature to systematically evaluate the diagnostic potential of circulating miRNAs in PC. Eligible studies were searched in PubMed, Embase and Chinese National Knowledge Infrastructure databases. Sensitivity and specificity were pooled using a random-effects model and were used to plot the summary receiver operator characteristic (SROC) curve. All analyses were performed using the Stata 13.0 software and Meta-Disc 1.4 for windows. A total of ten articles were included for the meta-analysis according to the inclusion criteria. The pooled results based on all included studies showed circulating miRNAs have a relatively good diagnostic performance, with a sensitivity of 0.74, a specificity of 0.71 and an area under SROC curve (AUC) of 0.77 in indiscriminating PC from controls. Furthermore, meta-regression and subgroup analyses indicate that multiple circulating miRNAs detection displayed a better diagnostic performance than single one, with an AUC rising from 0.75 to 0.81. Additional interesting finding was that Caucasian-based circulating miRNAs assays could reach a higher accuracy compared with non-Caucasian-based one for PC with the p value of 0.0378. Our results confirmed the potential use of circulating miRNAs in the early diagnosis of PC, especially the combination of multiple circulating miRNAs. However, large-scale prospective studies are still needed to further validate our findings.