RESUMO
INTRODUCTION: Several micro ribonucleic acids (miRNAs) are deregulated in hepatocellular carcinoma (HCC). Others are linked to clinical pathological features of HCC. The goal of this study was to investigate whether miRNA-21 and miRNA-215 gene expression could be used as a non-invasive diagnostic tool to diagnose HCC. METHODOLOGY: The gene expression of mature miRNA -21 and miRNA -215 in serum was analysed retrospectively using singleplex TaqMan two-step stem-loop quantitative real-time reverse-transcription PCR in 40 patients with HCC, 40 with chronic hepatitis C virus (HCV) with cirrhosis and 40 apparently healthy controls. RESULTS: Expression of miRNA -21 was significantly more down regulated in patients with HCC than in those with non-cirrhotic HCV (P = 0.007; odds ratio = 5; 95% confidence interval 1.6-15.4). The receiver operating curve analysis of the ability of miRNA-21 expression to discriminate between HCC and non-cirrhotic HCV revealed an area under the curve of 0.712 with 70% sensitivity and 68% specificity at a cut-off of ≤ 1.4468. Thus, the expression level of miRNA -21 could discriminate HCC from non-cirrhotic HCV. Significant positive correlation was observed between expression levels of microRNA-21 and miRNA -215 (r = 0.783, p < 0.001), but no association was observed between expression level of miR-215 and HCC or chronic HCV (p = 0.474). CONCLUSIONS: MiRNA-21 may be a useful, non-invasive tool for diagnosing HCC. Non-cirrhotic HCV patients have five times the risk of developing HCC when the miRNA -21 level ≤ 1.4468.