Prospective evidence of a circulating microRNA signature as a non-invasive marker of hepatocellular carcinoma in HBV patients.

The predictive value of circulating microRNAs (miRNAs) in hepatitis B virus (HBV)-related hepatocellular carcinoma (HCC) has been demonstrated in retrospective studies, but it has rarely been tested in prospective studies. In a cohort of 373 cancer-free HBV patients with a median follow-up of 4.5 years, we measured the expression of 24 retrospectively identified HCC-related miRNAs in baseline serum samples. When we analyzed the prospective associations of miRNA expression with HCC risk using the Cox proportional hazards model, we found that 15 of the 24 miRNAs exhibited a significant association with HCC risk. In particular, 7 miRNAs (miR-122, miR-99a, miR-331, miR-125b, miR-23b, miR-92a, and miR-26a) were associated with an increased risk, and 8 miRNAs (miR-652, miR-23a, miR-27a, miR-34a, miR-145, miR-10a, miR-150, and let-7f) were associated with a decreased risk. Compared to HBV patients with a low miRNA-based risk score, those with a high miRNA-based risk score exhibited a significantly elevated HCC risk in both univariate (hazard ratio [HR] 6.56, 95% confidence interval [CI] 2.74-15.70) and multivariate (HR 3.57, 95% CI 1.34-9.48) analyses. The risk score significantly increased the HCC prediction performance of alpha-fetoprotein (concordance index increased from 0.68 to 0.82, P < 0.0001). In silico analyses indicated that the genes targeted by the 15 miRNAs are mainly enriched in the transforming growth factor-beta signaling pathway. Collectively, these results provide prospective evidence that circulating miRNAs serve as non-invasive markers for risk prediction of HCC in HBV patients.