The goal of this study was to determine whether an association exists between circulating microRNA (miRNA) levels and disease progression in chronic hepatitis C (CHC), whether plasma or extracellular vesicles (EVs) were optimal for miRNA measurement and their correlation with hepatic miRNA expression, and the mechanistic plausibility of this association. We studied 130 CHC patients prospectively followed over several decades. A comprehensive miRNA profile in plasma using microarray with 2578 probe sets showed 323 miRNAs differentially expressed between healthy individuals and CHC patients, but only six that distinguished patients with mild versus severe chronic hepatitis. Eventually, let‐7a/7c/7d‐5p and miR‐122‐5p were identified as candidate predictors of disease progression. Cross‐sectional analyses at the time of initial liver biopsy showed that reduced levels of let‐7a/7c/7d‐5p (let‐7s) in plasma were correlated with advanced histological hepatic fibrosis stage and other fibrotic markers, whereas miR‐122‐5p levels in plasma were positively correlated with inflammatory activity, but not fibrosis. Measuring let‐7s levels in EVs was not superior to intact plasma for discriminating significant hepatic fibrosis. Longitudinal analyses in 60 patients with paired liver biopsies showed that let‐7s levels in plasma markedly declined over time in parallel with fibrosis progression. However, circulating let‐7s levels did not parallel those in the liver. Conclusion: Of all miRNAs screened, the let‐7 family showed the best correlation with hepatic fibrosis in CHC. A single determination of let‐7s levels in plasma did not have superior predictive value for significant hepatic fibrosis compared with that of fibrosis‐4 index, but the rate of let‐7s decline in paired longitudinal samples correlated well with fibrosis progression. Pathway analysis suggested that low levels of let‐7 may influence hepatic fibrogenesis through activation of transforming growth factor β signaling in hepatic stellate cells. (Hepatology 2016;64:732‐745)

Background: We recently identified 39 human microRNAs, which effectively suppress hepatitis B virus (HBV) replication in hepatocytes. Chronic HBV infection often results in active, hepatitis-related liver fibrosis; hence, we assessed whether any of these microRNAs have anti-fibrotic potential and predicted that miR-6133-5p may target several fibrosis-related genes. Methods: The hepatic stellate cell line LX-2 was transfected with an miR-6133-5p mimic and subsequently treated with Transforming growth factor (TGF)-β. The mRNA and protein products of the COL1A1 gene, encoding collagen, and the ACTA2 gene, an activation marker of hepatic stellate cells, were quantified. Results: The expression of COL1A1 and ACTA2 was markedly reduced in LX-2 cells treated with miR-6133-5p. Interestingly, phosphorylation of c-Jun N-terminal kinase (JNK) was also significantly decreased by miR-6133-5p treatment. The expression of several predicted target genes of miR-6133-5p, including TGFBR2 (which encodes Transforming Growth Factor Beta Receptor 2) and FGFR1 (which encodes Fibroblast Growth Factor Receptor 1), was also reduced in miR-6133-5p-treated cells. The knockdown of TGFBR2 by the corresponding small interfering RNA greatly suppressed the expression of COL1A1 and ACTA2. Treatment with the JNK inhibitor, SP600125, also suppressed COL1A1 and ACTA2 expression, indicating that TGFBR2 and JNK mediate the anti-fibrotic effect of miR-6133-5p. The downregulation of FGFR1 may result in a decrease of phosphorylated Akt, ERK (extracellular signal-regulated kinase), and JNK. Conclusion: miR-6133-5p has a strong anti-fibrotic effect, mediated by inactivation of TGFBR2, Akt, and JNK.

Background and Aims: Durvalumab plus tremelimumab (Dur/Tre) therapy is expected to have good therapeutic efficacy for patients with unresectable hepatocellular carcinoma (u‐HCC). We previously reported that the neutrophil‐to‐lymphocyte ratio (NLR) during atezolizumab plus bevacizumab therapy in u‐HCC patients was a useful marker for predicting the therapeutic response. Therefore, we investigated whether the NLR during Dur/Tre therapy could predict treatment outcomes in patients with u‐HCC.Design: The present study included 64 u‐HCC patients treated with Dur/Tre and evaluated for their initial response by dynamic computed tomography or magnetic resonance imaging at least once until December 2024. Alpha‐fetoprotein (AFP) and des‐gamma‐carboxyprothrombin (DCP) ratios were defined as follows: the pretreatment levels of AFP and DCP were set to 1, and the AFP and DCP ratios to pretreatment were calculated at the start of the second course of Dur/Tre therapy.Results: Of the 64 HCC patients, 34 patients (53%) achieved a disease control rate (non‐PD) at the initial evaluation. The NLR at the start of the second course (NLR‐2c) tended to be lower in patients with non‐PD than progressive disease (p = 0.133), and the optimal cutoff value was 5.75. Patients with NLR‐2c ≥ 5.75 had a shorter progression‐free survival (PFS) than those with NLR‐2c < 5.75 (median: 1.7 vs. 5.5 months, p = 0.002). Multivariate analysis showed that NLR‐2c ≥ 5.75 (HR 4.66; p < 0.001) and AFP ratio ≥ 0.933 (HR 4.32; p = 0.004) were significantly associated with poor PFS.Conclusions: The NLR‐2c value is useful for predicting PFS in u‐HCC patients treated with Dur/Tre therapy.