Objective: The aim of this study is to determine the role of serum exosomal miRNAs as potential non-invasive biomarkers for distinguishing no-or-mild fibrosis from significant fibrosis in patients with chronic hepatitis B (CHB).
Methods: Next-generation sequencing was used to identify fibrosis-related serum exosomal miRNAs in 9 CHB patients. The candidate exosomal miRNAs were further validated by qRT-PCR in 282 CHB patients. Receiver operating characteristic curves were generated to assess the diagnostic performance of exosomal miRNAs and other non-invasive models.
Results: Seventy-two miRNAs were differentially expressed in serum exosomes between patients with no-or-mild fibrosis and significant fibrosis. The expression of serum exosomal miR-92a-3p and miR-146a-5p progressively increased with the aggravation of liver fibrosis in the validation cohort. Multivariate analysis identified miR-92a-3p (P<0.001), miR-146a-5p (P<0.001), and liver stiffness measurement (LSM) (P=0.012) as independent predictors for significant fibrosis. The area under the receiver operating characteristic curve (AUROC) of exosomal miR-92a-3p (AUROC=0.88) was significantly higher than that of APRI (aspartate aminotransferase-to-platelet ratio index) (AUROC=0.72, P<0.001), FIB-4 (AUROC=0.71, P<0.001), and LSM (AUROC=0.80, P=0.022) for identifying significant fibrosis. Similarly, the AUROC of exosomal miR-146a-5p (AUROC=0.82) was also significantly better than that of APRI (AUROC=0.72, P=0.009), FIB-4 (AUROC=0.71, P=0.002), and comparable to LSM (AUROC=0.80, P=0.551) for discriminating significant fibrosis.
Conclusion: Serum exosomal miR-92a-3p and miR-146a-5p are superior to APRI, FIB-4, and LSM for diagnosing significant fibrosis in CHB patients and offer a promising non-invasive alternative to liver biopsy.