Circulating exosome DANCR correlated to the recurrence of hepatitis C virus-related hepatocellular carcinoma.

Abstract

e13688 Background: Long non-coding RNAs (lncRNAs) have been associated with various types of neoplasms. Hepatitis C virus (HCV)-related hepatocellular carcinoma (HCC) has high risk of recurrence. Methods: Differentially-expressed candidate lncRNAs relevant to HCV-HCC were identified by RNA-seq in Screening set, validated by qPCR in Validation set, and confirmed in external Test cohort. Target lncRNAs in tissue and serum exosome were applied to predict HCC recurrence of HCV-HCC after curative surgical resection in a large Application cohort. Pathogenetic mechanisms of target lncRNA were explored by using JFH1-infectious cells. Results: Of the top ten differentially-expressed lncRNAs relevant to HCV-related HCC identified in Screening set, differentiation antagonizing non-protein coding RNA (DANCR), which was upregulated by HCV infection and identified as the most relevant lncRNA to HCV-HCC, was overexpressed in tumor than in adjacent non-tumor (ANT) tissues. Of 183 HCV-HCC patients followed for 10 years after curative HCC resection, tumor DANCR, tumor/ANT DANCR ratio and circulating exosome DANCR levels were positively associated with HCC recurrence. Circulating exosome DANCR levels by droplet digital PCR provided the best predictive power of HCC recurrence with area under the curve of 0.88, when compared to tumor DANCR levels, tumor/ANT DANCR ratio, and alfa-fetoprotein. Exosome DANCR > 50 copies/ml was the most predictive factor associated with HCC recurrence and mortality (hazard ratio/95% confidence intervals: 7.0/4.3-11.6 and 2.7/1.5-5.1 respectively, Cox regression model). Cell experiments showed that DANCR, positively associated with mesenchymal-associated β-catenin expression, promoted cell migration and invasion ability. Conclusions: lncRNA-DANCR was highly relevant to disease progression of HCV-HCC. Circulating exosome DANCR could serve as a non-invasive prognostic biomarker for HCV-HCC.