Serum microRNA characterization identifies miR-885-5p as a potential marker for detecting liver pathologies

Circulating miRNAs (microRNAs) are emerging as promising biomarkers for several pathological conditions, and the aim of this study was to investigate the feasibility of using serum miRNAs as biomarkers for liver pathologies. Real-time qPCR (quantitative PCR)-based TaqMan MicroRNA arrays were first employed to profile miRNAs in serum pools from patients with HCC (hepatocellular carcinoma) or LC (liver cirrhosis) and from healthy controls. Five miRNAs (i.e. miR-885-5p, miR-574-3p, miR-224, miR-215 and miR-146a) that were up-regulated in the HCC and LC serum pools were selected and further quantified using real-time qPCR in patients with HCC, LC, CHB (chronic hepatitis B) or GC (gastric cancer) and in normal controls. The present study revealed that more than 110 miRNA species in the serum samples and wide distribution ranges of serum miRNAs were observed. The levels of miR-885-5p were significantly higher in sera from patients with HCC, LC and CHB than in healthy controls or GC patients. miR-885-5p yielded an AUC [the area under the ROC (receiver operating characteristic) curve] of 0.904 [95% CI (confidence interval), 0.837-0.951, P<0.0001) with 90.53% sensitivity and 79.17% specificity in discriminating liver pathologies from healthy controls, using a cut off value of 1.06 (normalized). No correlations between increased miR-885-5p and liver function parameters [AFP (α-fetoprotein), ALT (alanine aminotransferase), AST (aspartate aminotransferase) and GGT (γ-glutamyl transpeptidase)] were observed in patients with liver pathologies. In summary, miR-885-5p is significantly elevated in the sera of patients with liver pathologies, and our data suggest that serum miRNAs could serve as novel complementary biomarkers for the detection and assessment of liver pathologies.