Hepatitis B virus X protein impairs α-interferon signaling via up-regulation of suppressor of cytokine signaling 3 and protein phosphatase 2A.

Hepatitis B Virus (HBV) causes liver cirrhosis and hepatocellular carcinoma. Standard therapy includes treatment with interferon (IFN); however, its efficacy is limited. HBV has been reported to impair IFN signaling; however, the mechanism is unclear. Here, the relationship between HBV X protein (HBx) and IFN signaling was investigated by establishing HepG2 cells, stably expressing HBx (HepG2/HBx) via retrovirus-mediated gene transfer. Subsequently, IFN negative-regulator expression and its mechanism were studied. HepG2/HBx cells showed reduced expression of IFN-stimulated genes and expressed higher levels of suppressor of cytokine signaling 3 (SOCS3) and protein phosphatase 2A (PP2A) suppressor compared with control cells. Knockdown of SOCS3 and PP2A restored IFN sensitivity. Moreover, HepG2/HBx cells showed higher phosphorylation levels of signal transducers and activators of transcription 3 and endoplasmic reticulum stress, which are inducers of SOCS3 and PP2A, respectively. Additionally, HBx-knockdown restored IFN sensitivity in HepG2.2.15.7 cells. It was also confirmed that SOCS3 and PP2A expression levels were up-regulated in the liver of patients with HBV infection. The results of this study demonstrated that HBx impairs IFN signaling via increased expression of SOCS3 and PP2A, a novel mechanistic insight, providing a potential therapeutic target to enhance the efficiency of IFN therapy. J. Med. Virol. 89:267-275, 2017. © 2016 Wiley Periodicals, Inc.

Combination of neutrophil-to-lymphocyte ratio and early des-γ-carboxyprothrombin change ratio as a useful predictor of treatment response for hepatic arterial infusion chemotherapy against advanced hepatocellular carcinoma.

AIM: Hepatic arterial infusion chemotherapy (HAIC) is a potent therapeutic option for advanced hepatocellular carcinoma (HCC). However, there are few known predictive factors of treatment response to HAIC. We clarified the most accurate predictive factors early on in treatment. METHODS: Study subjects were 70 patients with advanced HCC who had been treated with HAIC. We assessed the relationships between patient characteristics, change ratios of early tumor markers, tumor response, progression-free survival (PFS), and overall survival. RESULTS: After two courses of HAIC, 1 (1.4%), 16 (22.9%), 30 (42.8%), and 23 (32.9%) of the 70 patients showed complete response, partial response, stable disease, and progressive disease, respectively. Overall survival was related to Child-Turcotte-Pugh score, extrahepatic metastasis, and the des-γ-carboxyprothrombin (DCP) response. Univariate and multivariate analyses identified the neutrophil-to-lymphocyte ratio (NLR) and DCP response as significant determinants of treatment response and PFS. Progression-free survival with a low NLR (<2.87) was significantly longer than with a high NLR (median, 8.4 months vs. 2.8 months, respectively). Progression-free survival was 7.2 months for patients with a responsive DCP (<0.7) and 2.3 months for an unresponsive DCP (≥0.7). Additionally, even with baseline high NLR, patients with responsive DCP achieved better PFS. CONCLUSION: Baseline NLR and early DCP response were significant predictors of treatment response and PFS after HAIC for patients with advanced HCC. The combination of baseline NLR and early DCP response could be accurate and useful predictive factors of response to HAIC and could help optimize treatments for patients with advanced HCC.

Prevalence and characteristics of naturally occurring sofosbuvir resistance-associated variants in patients with hepatitis C virus genotype 1b infection.

AIM: Sofosbuvir (SOF), a nucleotide analog pro-drug, targets hepatitis C virus (HCV) NS5B polymerase and shows potential for treating HCV infection, given its high efficacy and good barrier to resistance. However, in addition to the rare resistant-associated variant (RAV) of non-structural protein NS5B S282T, several new potential RAVs of SOF have been reported, especially related to HCV genotype 1b. However, the prevalence and characteristics of these RAVs have not been clarified. METHODS: We analyzed the prevalence of variants in the NS3/NS5A/NS5B regions in 96 patients treated with simeprevir (SMV) combination therapy, and the prevalence of RAVs in patients showing treatment failure was determined by direct- or deep-sequencing methods. Associations between these potential RAVs and clinical factors were also analyzed. RESULTS: Prevalence of NS5B RAV C316N was high (46.9%, 45/96), whereas that of NS5B L159F was relatively low (1.04%, 1/96); however, deep sequencing showed that 30.0% of patients with C316N also had NS5B RAV L159F. Additionally, there was no significant relationship between the existence of potential NS5B and NS5A or NS3 RAVs. However, the presence of NS5B C316N was significantly associated with an HCV core amino acid 91 substitution. No significant difference was detected between each RAV and sustained virological response in simeprevir combination therapy. CONCLUSION: We provide clear evidence of the high prevalence of two potential naturally occurring NS5B RAVs (C316N and L159F) in Japan. It may be important to pay particular attention to these new potential RAVs, especially when using SOF-based therapy in patients with RAVs due to previous direct-acting antiviral therapy failure.

Efficacy and safety of daclatasvir and asunaprevir combination therapy in chronic hemodialysis patients with chronic hepatitis C.

BACKGROUND: HCV infection in chronic hemodialysis patients is high, has a poor prognosis and high risk of renal graft failure, and requires nosocomial infection control measures. However, options of anti-HCV therapy in such patients are limited and unsatisfactory. In this study, we report effectiveness and safety of HCV-NS5A-inhibitor daclatasvir (DCV) and protease-inhibitor asunaprevir (ASV) combination therapy for hemodialysis patients with HCV infection. METHODS: This study was registered at the UMIN Clinical Trials Registry as UMIN000016355. Thirty-four dialysis patients were treated with DCV/ASV combination therapy between January 2015 and November 2015. Of those, 21 patients who were followed more than 12 weeks after treatment ended were included. We evaluated the 12-week sustained virologic response (SVR12) and adverse events during treatment. RESULTS: Of the 21 patients, four had compensated liver cirrhosis and three had resistance-associated variant of NS5A (NS5A RAVs)-Y93H at baseline. Overall, total of 95.5 % (20/21) of the patients achieved SVR12. Of note, all patients with cirrhosis or NS5A RAVs achieved SVR12. One relapser patient at 4 weeks post-treatment had NS3 D168E RAVs at baseline. A total of 20 patients (95.5 %) completed the 24-week therapy. One patient discontinued treatment at week 12 due to ALT elevations and achieved SVR12. CONCLUSIONS: DAV and ASV combination therapy for chronic hemodialysis patients with HCV infection was highly effective and well tolerated, even in elderly patients and patients with liver cirrhosis and NS5A-RAVs.