Transforming Growth Factor ß Acts as a Regulatory Molecule for Lipogenic Pathways among Hepatitis C Virus Genotype-Specific Infections.

Hepatitis C virus (HCV) infection promotes metabolic disorders, and the severity of lipogenic disease depends upon the infecting virus genotype. Here, we have examined HCV genotype 1-, 2-, or 3-specific regulation of lipid metabolism, involving transforming growth factor ß (TGF-ß)-regulated phospho-Akt (p-Akt) and peroxisome proliferator-activated receptor alpha (PPARα) axes. Since HCV core protein is one of the key players in metabolic regulation, we also examined its contribution in lipid metabolic pathways. The expression of regulatory molecules, TGF-ß1/2, phospho-Akt (Ser473), PPARα, sterol regulatory element-binding protein 1 (SREBP-1), fatty acid synthase (FASN), hormone-sensitive lipase (HSL), and acyl dehydrogenases was analyzed in virus-infected hepatocytes. Interestingly, HCV genotype 3a exhibited much higher activation of TGF-ß and p-Akt, with a concurrent decrease in PPARα expression and fatty acid oxidation. A significant and similar decrease in HSL, unlike in HCV genotype 1a, was observed with both genotypes 2a and 3a. Similar observations were made from ectopic expression of the core genomic region from each genotype. The key role of TGF-ß was further verified using specific small interfering RNA (siRNA). Together, our results highlight a significant difference in TGF-ß-induced activity for the HCV genotype 2a- or 3a-induced lipogenic pathway, exhibiting higher triglyceride synthesis and a decreased lipolytic mechanism. These results may help in therapeutic modalities for early treatment of HCV genotype-associated lipid metabolic disorders.IMPORTANCE Hepatic steatosis is a frequent complication associated with chronic hepatitis C virus (HCV) infection and is a key prognostic indicator for progression to fibrosis and cirrhosis. Several mechanisms are proposed for the development of steatosis, especially with HCV genotype 3a. Our observations suggest that transforming growth factor ß (TGF-ß) and peroxisome proliferator-activated receptor alpha (PPARα)-associated mechanistic pathways in hepatocytes infected with HCV genotype 2a and 3a differ from those in cells infected with genotype 1a. The results suggest that a targeted therapeutic approach for enhanced PPARα and lipolysis may reduce HCV genotype-associated lipid metabolic disorder in liver disease.

Co-Occurrence of Hepatitis A Infection and Chronic Liver Disease.

Hepatitis A virus (HAV) infection occasionally leads to a critical condition in patients with or without chronic liver diseases. Acute-on-chronic liver disease includes acute-on-chronic liver failure (ACLF) and non-ACLF. In this review, we searched the literature concerning the association between HAV infection and chronic liver diseases in PubMed. Chronic liver diseases, such as metabolic associated fatty liver disease and alcoholic liver disease, coinfection with other viruses, and host genetic factors may be associated with severe hepatitis A. It is important to understand these conditions and mechanisms. There may be no etiological correlation between liver failure and HAV infection, but there is an association between the level of chronic liver damage and the severity of acute-on-chronic liver disease. While the application of an HAV vaccination is important for preventing HAV infection, the development of antivirals against HAV may be important for preventing the development of ACLF with HAV infection as an acute insult. The latter is all the more urgent given that the lives of patients with HAV infection and a chronic liver disease of another etiology may be at immediate risk.

Noninvasive Assessment of Liver Fibrosis: Current and Future Clinical and Molecular Perspectives.

Liver fibrosis is one of the risk factors for hepatocellular carcinoma (HCC) development. The staging of liver fibrosis can be evaluated only via a liver biopsy, which is an invasive procedure. Noninvasive methods for the diagnosis of liver fibrosis can be divided into morphological tests such as elastography and serum biochemical tests. Transient elastography is reported to have excellent performance in the diagnosis of liver fibrosis and has been accepted as a useful tool for the prediction of HCC development and other clinical outcomes. Two-dimensional shear wave elastography is a new technique and provides a real-time stiffness image. Serum fibrosis markers have been studied based on the mechanism of fibrogenesis and fibrolysis. In the healthy liver, homeostasis of the extracellular matrix is maintained directly by enzymes called matrix metalloproteinases (MMPs) and their specific inhibitors, tissue inhibitors of metalloproteinases (TIMPs). MMPs and TIMPs could be useful serum biomarkers for liver fibrosis and promising candidates for the treatment of liver fibrosis. Further studies are required to establish liver fibrosis-specific markers based on further clinical and molecular research. In this review, we summarize noninvasive fibrosis tests and molecular mechanism of liver fibrosis in current daily clinical practice.

Different Mechanisms of Action of Regorafenib and Lenvatinib on Toll-Like Receptor-Signaling Pathways in Human Hepatoma Cell Lines.

Multiple kinase inhibitors are available for patients with advanced hepatocellular carcinoma (HCC). It is largely unknown whether regorafenib or lenvatinib modulates innate immunity including Toll-like receptor (TLR)-signaling pathways in HCC. We performed real-time RT-PCR to investigate 84 TLR-associated gene expression levels and compared these gene expression levels in each hepatoma cells treated with or without regorafenib or lenvatinib. In response to regorafenib, nine and 10 genes were upregulated in Huh7 and HepG2 cells, respectively, and only C-X-C motif chemokine ligand 10 was upregulated in both cell lines. A total of 14 and 12 genes were downregulated in Huh7 and HepG2 cells, respectively, and two genes (Fos proto-oncogene, AP-1 transcription factor subunit, and ubiquitin conjugating enzyme E2 N) were downregulated in both cell lines. In response to lenvatinib, four and 16 genes were upregulated in Huh7 and HepG2 cells, respectively, and two genes (interleukin 1 alpha and TLR4) were upregulated in both cells. Six and one genes were downregulated in Huh7 and HepG2, respectively, and no genes were downregulated in both cell lines. In summary, regorafenib and lenvatinib affect TLR signaling pathways in human hepatoma cell lines. Modulation of TLR signaling pathway may improve the treatment of HCC patients with refractory disease.

Association between MicroRNA-373 and Long Noncoding RNA NORAD in Hepatitis C Virus-Infected Hepatocytes Impairs Wee1 Expression for Growth Promotion.

Chronic hepatitis C virus (HCV) infection may lead to end-stage liver disease, including hepatocellular carcinoma (HCC). We have shown previously that microRNA-373 (miR-373) is upregulated in HCV-infected human liver biopsy specimens. To gain insight into the role of miR-373 in HCV-mediated pathogenesis, we investigated its interacting partner for hepatocyte growth regulation. Transcriptome sequencing (RNA-seq) data revealed that Wee1 is associated with miR-373 and is a direct target. Interestingly, higher expression of Wee1 was noted in HCV-infected hepatocytes than in uninfected hepatocytes, suggesting that other factors may block miR-373-mediated Wee1 inhibition. We subsequently found an association between the long noncoding RNA NORAD (LINC00657) and miR-373, and we demonstrated that NORAD binds to miR-373 and Wee1 independently. However, the high level of Wee1 expression in HCV-infected hepatocytes suggested that miR-373 forms a complex with NORAD. Depletion of miR-373 or the inhibitor Wee1 reduces the growth of Huh7.5 cells harboring the HCV genome as well as reducing Wee1 expression. Taken together, our data demonstrate a novel mechanism of hepatocyte growth promotion during HCV infection involving a miR-373-NORAD-Wee1 axis, which may be a target for future therapy against HCV-associated HCC.IMPORTANCE The mechanism of HCV-mediated liver pathogenesis is poorly understood. In this study, we observed that HCV infection upregulates miR-373 and Wee1, a pivotal player in the G2 checkpoint in the cell cycle, although Wee1 is a direct target for miR-373. Subsequent investigation demonstrated that miR-373 forms a complex with the long noncoding RNA NORAD, resulting in the release of their common target, Wee1, in HCV-infected cells, which, in turn, favors uncontrolled cell growth. Our study suggested a previously unknown mechanism for hepatocyte growth promotion following HCV infection, and this pathway can be targeted for future therapy against HCV-mediated liver pathogenesis.

Rapid hepatitis C virus clearance by antivirals correlates with immune status of infected patients.

Altered immune parameters associated with hepatitis C virus (HCV) genotype 1b infection and their correlation with virus eradication in direct-acting antivirals (DAA)-treated patients were examined. Thirty-one HCV-infected patients were treated with DAAs for 12 weeks. Pre-DAA-treatment and post-DAA-treatment sera were analyzed for cytokines/chemokines using MILLIPLEX MAP. Serum complement level and antibody neutralization activity were measured separately. Sera from 11 spontaneously cleared HCV subjects were included for comparison. Rapid virological responders (RVR) or end-of-treatment responders (EOTR) were defined as patients with HCV RNA negative at week 4 or positive at week 4 and negative at week 12, respectively. HCV RNA eradication and a decrease in liver fibrosis-related cytokines after treatment were observed when compared with pretreatment sera from RVR and EOTR. In pretreatment sera, interferons and T-helper 1 or 2 cell-associated cytokines/chemokines were significantly higher among RVR as compared with EOTR. Furthermore, serum complement and virus neutralizing antibody levels were higher in pretreatment RVR sera. Eradication of HCV RNA by DAA decreased liver fibrosis-related cytokines. Pretreatment sera from RVR displayed an enhanced cytokine/chemokine, complement and virus neutralizing antibody response as compared with EOTR sera. Our results suggested that enhanced host immune status may play an additive role on HCV RNA clearance by DAA.

Superinfection of hepatitis A virus in hepatocytes infected with hepatitis B virus.

Hepatitis A virus (HAV) infection is a major cause of acute hepatitis including acute liver failure. Hepatitis B infection (HBV) occurs worldwide, with the highest rates in Asian and African countries, and there are several reports that HAV infection may have a more severe clinical course in patients with chronic HBV infection. We previously demonstrated that Japanese miso extracts have inhibitory effects on HAV replication. In the present study, we examined the replication of HAV and HBV in a hepatocyte superinfection model and the inhibitory effects of Japanese miso extracts on both viruses. According to the results, HAV infection inhibited HBV replication in superinfected hepatocytes, and Japanese rice-koji miso extracts had inhibitory effects on HAV replication. Our findings provide useful information for clinicians in managing HAV infection in patients with chronic HBV infection.

Exosomes and Hepatocellular Carcinoma: From Bench to Bedside.

As hepatocellular carcinoma (HCC) usually occurs in the background of cirrhosis, which is an end-stage form of liver diseases, treatment options for advanced HCC are limited, due to poor liver function. The exosome is a nanometer-sized membrane vesicle structure that originates from the endosome. Exosome-mediated transfer of proteins, DNAs and various forms of RNA, such as microRNA (miRNA), long noncoding RNA (lncRNA) and messenger RNA (mRNA), contributes to the development of HCC. Exosomes mediate communication between both HCC and non-HCC cells involved in tumor-associated cells, and several molecules are implicated in exosome biogenesis. Exosomes may be potential diagnostic biomarkers for early-stage HCC. Exosomal proteins, miRNAs and lncRNAs could provide new biomarker information for HCC. Exosomes are also potential targets for the treatment of HCC. Notably, further efforts are required in this field. We reviewed recent literature and demonstrated how useful exosomes are for diagnosing patients with HCC, treating patients with HCC and predicting the prognosis of HCC patients.

Hepatitis C Virus Core Protein Modulates Endoglin (CD105) Signaling Pathway for Liver Pathogenesis.

Endoglin is part of the TGF-ß receptor complex and has a crucial role in fibrogenesis and angiogenesis. It is also an important protein for tumor growth, survival, and cancer cell metastasis. In a previous study, we have shown that hepatitis C virus (HCV) infection induces epithelial-mesenchymal transition (EMT) state and cancer stem-like cell (CSC) properties in human hepatocytes. Our array data suggested that endoglin (CD105) mRNA is significantly upregulated in HCV-associated CSCs. In this study, we have observed increased endoglin expression on the cell surface of an HCV core-expressing hepatocellular carcinoma (HepG2) cell line or immortalized human hepatocytes (IHH) and activation of its downstream signaling molecules. The status of phospho-SMAD1/5 and the expression of inhibitor of DNA binding protein 1 (ID1) were upregulated in HCV-infected cells or viral core gene-transfected cells. Additionally, we observed upregulation of endoglin/ID1 mRNA expression in chronic HCV patient liver biopsy samples. CSC generation by HCV core protein was dependent on the endoglin signaling pathway using activin receptor-like kinase 1 (ALK1) Fc blocking peptide and endoglin small interfering RNA (siRNA). Further, follow-up from in vitro analysis suggested that the antiapoptosis Bcl2 protein, proliferation-related cyclin D1 protein, and CSC-associated Hes1, Notch1, Nanog, and Sox2 proteins are enhanced during infection or ectopic expression of HCV core protein.IMPORTANCE Endoglin plays a crucial role in fibrogenesis and angiogenesis and is an important protein for tumor growth, survival, and cancer cell metastasis. Endoglin enhances ALK1-SMAD1/5 signaling in different cell types, leading to increased proliferation and migration responses. We have observed endoglin expression on the HCV core-expressing cell surface of human hepatocyte origin and activation of phospho-SMAD1/5 and ID1 downstream signaling molecules. ID1 protein plays a role in CSC properties, and we found that this pathway is important for antiapoptotic and cell proliferation signaling. Blocking of endoglin-ALK1-SMAD1/5 might be a good candidate for therapy for liver cancer stem cells together with liver cirrhosis.

Exosome-Mediated Intercellular Communication between Hepatitis C Virus-Infected Hepatocytes and Hepatic Stellate Cells.

Fibrogenic pathways in the liver are principally regulated by activation of hepatic stellate cells (HSC). Fibrosis is associated with chronic hepatitis C virus (HCV) infection, although the mechanism is poorly understood. HSC comprise the major population of nonparenchymal cells in the liver. Since HCV does not replicate in HSC, we hypothesized that exosomes secreted from HCV-infected hepatocytes activate HSC. Primary or immortalized human hepatic stellate (LX2) cells were exposed to exosomes derived from HCV-infected hepatocytes (HCV-exo), and the expression of fibrosis-related genes was examined. Our results demonstrated that HCV-exo internalized to HSC and increased the expression of profibrotic markers. Further analysis suggested that HCV-exo carry miR-19a and target SOCS3 in HSC, which in turn activates the STAT3-mediated transforming growth factor ß (TGF-ß) signaling pathway and enhances fibrosis marker genes. The higher expression of miR-19a in exosomes was also observed from HCV-infected hepatocytes and in sera of chronic HCV patients with fibrosis compared to healthy volunteers and non-HCV-related liver disease patients with fibrosis. Together, our results demonstrated that miR-19a carried through the exosomes from HCV-infected hepatocytes activates HSC by modulating the SOCS-STAT3 axis. Our results implicated a novel mechanism of exosome-mediated intercellular communication in the activation of HSC for liver fibrosis in HCV infection.IMPORTANCE HCV-associated liver fibrosis is a critical step for end-stage liver disease progression. However, the molecular mechanisms for hepatic stellate-cell activation by HCV-infected hepatocytes are underexplored. Here, we provide a role for miR-19a carried through the exosomes in intercellular communication between HCV-infected hepatocytes and HSC in fibrogenic activation. Furthermore, we demonstrate the role of exosomal miR-19a in activation of the STAT3-TGF-ß pathway in HSC. This study contributes to the understanding of intercellular communication in the pathogenesis of liver disease during HCV infection.

Hepatitis C virus-induced tumor-initiating cancer stem-like cells activate stromal fibroblasts in a xenograft tumor model.

Hepatitis C virus (HCV) often causes persistent infection and is an increasingly important factor in the etiology of fibrosis/cirrhosis and hepatocellular carcinoma, although the mechanisms for the disease processes remain unclear. We have shown previously that HCV infection generates an epithelial-mesenchymal transition state and tumor-initiating cancer stem-like cells in human hepatocytes. In this study, we investigated whether HCV-induced tumor-initiating cancer stem-like cells when implanted into mice activate stromal fibroblasts. A number of fibroblast activation markers, including matrix metalloproteinase 2, were significantly increased at the mRNA or protein level in the xenograft tumors, suggesting the presence of tumor-associated fibroblasts. Fibroblast activation markers of murine origin were specifically increased in tumor, suggesting that fibroblasts migrate to form stroma. Next, we demonstrated that conditioned medium from HCV-infected human hepatocytes activates fibrosis-related markers in hepatic stellate cells. We further observed that these HCV-infected hepatocytes express transforming growth factor beta, which activates stromal fibroblast markers. Subsequent analysis suggested that anti-transforming growth factor beta neutralizing antibody, when incubated with conditioned medium from HCV-infected hepatocytes, inhibits fibrosis marker activation in primary human hepatic stellate cells. CONCLUSION: HCV-infected hepatocytes induce local fibroblast activation by secretion of transforming growth factor beta, and a preneoplastic or tumor state of the hepatocytes influences the network for the tumor-associated fibroblast environment. (Hepatology 2017;66:1766-1778).

Hepatitis C virus-induced CCL5 secretion from macrophages activates hepatic stellate cells.

Hepatitis C virus (HCV)-mediated chronic liver disease is a serious health problem around the world and often causes fibrosis/cirrhosis and hepatocellular carcinoma. The mechanism of liver disease progression during HCV infection is still unclear, although inflammation is believed to be an important player in disease pathogenesis. We previously reported that macrophages including Kupffer cells exposed to HCV induce proinflammatory cytokines. These secreted cytokines may activate hepatic stellate cells (HSCs) toward fibrosis. In this study, we examined crosstalk between macrophages and HSCs following HCV infection. Primary human HSCs and immortalized HSCs (LX2 cells) were incubated with conditioned medium derived from HCV-exposed human macrophages. Expression of inflammasome and fibrosis-related genes in these cells was examined, with increased expression of inflammatory (NLR family pyrin domain containing 3, interleukins 1ß and 6, and cysteine-cysteine chemokine ligand 5 [CCL5]) and profibrogenic (transforming growth factor ß1, collagen type 4 alpha 1, matrix metalloproteinase 2, and alpha-smooth muscle actin) markers. Further investigation suggested that CCL5, secreted from HCV-exposed macrophages, activates inflammasome and fibrosis markers in HSCs and that neutralizing antibody to CCL5 inhibited activation. CONCLUSION: Together, our results demonstrate that human macrophages exposed to HCV induce CCL5 secretion, which plays a significant role in hepatic inflammation and fibrosis. (Hepatology 2017;66:746-757).

Interferon induces interleukin 8 and bone marrow stromal cell antigen 2 expression, inhibiting the production of hepatitis B virus surface antigen from human hepatocytes.

Hepatitis B virus (HBV) surface antigen (HBsAg) loss is one of the treatment goals of chronic HBV infection. Bone marrow stromal cell antigen 2 (BST2) is one of the interferon (IFN)-stimulated genes (ISGs) and inhibits the release of various enveloped viruses. Here we examined the effects of antiviral treatment on HBsAg levels and its intracellular mechanism in HBsAg-producing hepatocytes. In PLC/PRF/5 and Huh1, IFNα-2a treatment decreased HBsAg levels in their conditioned media. Upregulation of interleukin 8 (IL8), toll-like receptor 2 (TLR2) and interferon gamma-induced protein 10 (IP10) mRNAs was associated with the reduction of HBsAg in both PLC/PRF/5 and Huh1. The HBsAg level was upregulated by knockdown of IL8, TLR2 or IP10. Exogenous addition of IL8 enhanced BST2 promoter activity and BST2 mRNA expression. Additionally, knockdown of IL8 could lead to the downregulation of BST2 mRNA. Transfection of poly(I-C) enhanced IL8 and BST2 mRNA expression and inhibited HBsAg secretion from PLC/PRF/5 cells. In conclusion, IL8 might play an important role in the enhancement of BST2 and be involved in HBsAg eradication.

Real-World Experiences with the Combination Treatment of Ledipasvir plus Sofosbuvir for 12 Weeks in HCV Genotype 1-Infected Japanese Patients: Achievement of a Sustained Virological Response in Previous Users of Peginterferon plus Ribavirin with HCV NS3/4A Inhibitors.

The aim of this study was to characterize the treatment response and serious adverse events of ledipasvir plus sofosbuvir therapies in Japanese patients infected with hepatitis C virus (HCV) genotype 1 (GT1). This retrospective study analyzed 240 Japanese HCV GT1 patients treated for 12 weeks with 90 mg of ledipasvir plus 400 mg of sofosbuvir daily. Sustained virological response at 12 weeks post-treatment (SVR12) was achieved in 236 of 240 (98.3%) patients. Among treatment-naïve patients, SVR12 was achieved in 136 of 138 (98.6%) patients, and among treatment-experienced patients, SVR12 was achieved in 100 of 102 (98.0%) patients. In patients previously treated with peginterferon plus ribavirin with various HCV NS3/4A inhibitors, 100% SVR rates (25/25) were achieved. Two relapsers had HCV NS5A resistance-associated variants (RAVs), but no HCV NS5B-S282 was observed after they relapsed. We experienced two patients with cardiac events during treatment. In conclusion, combination of ledipasvir plus sofosbuvir for 12 weeks is a potential therapy for HCV GT1 patients. Caution is needed for HCV NS5A RAVs, which were selected by HCV NS5A inhibitors and cardiac adverse events.

Successful sofosbuvir treatment with ribavirin dose reduction for chronic hepatitis C virus genotype 2 infection in a patient with ulcerative colitis: a case report.

BACKGROUND: Ulcerative colitis is a lifelong, immunologically mediated disease. Direct-acting antivirals (DAAs) are now available for the treatment of chronic hepatitis C virus (HCV) infection. An interferon-free regimen appears useful, safe and effective for many patients for whom interferon-based treatment is contraindicated. CASE PRESENTATION: We studied a 56-year-old treatment-naïve Japanese man with chronic HCV genotype 2b infection who had ulcerative colitis. This patient was treated with sofosbuvir and ribavirin for 12 weeks. During treatment, diarrhoea and bloody faeces were frequent. After ribavirin was reduced to 400 mg daily, these symptoms decreased. Finally, the patient achieved a sustained virologic response 12 weeks after the stoppage of the treatment. CONCLUSION: Clinicians should pay careful attention to the ribavirin dose in the treatment of certain HCV patients with inflammatory bowel disease who are receiving sofosbuvir plus ribavirin.

Daclatasvir plus Asunaprevir Treatment for Real-World HCV Genotype 1-Infected Patients in Japan.

Background. All-oral combination of direct-acting antivirals could lead to higher sustained virologic response (SVR) in hepatitis C virus (HCV)-infected patients. In the present study, we examined the efficacy and safety of the dual oral treatment with HCV nonstructural protein (NS) 5A inhibitor daclatasvir (DCV) plus HCV NS3/4A inhibitor asunaprevir (ASV) for 24 weeks in real-world HCV genotype 1-infected Japanese individuals. Methods. After screening for HCV NS5A resistance-associated variants (RAVs) by PCR invader assay, a total of 54 Japanese patients infected with HCV genotype 1 treated with DCV plus ASV were retrospectively analyzed. SVR12 was used for evaluation of the virologic response. Results. Of the total 54 patients, 46 patients (85.2%) were treated with DCV plus ASV for 24 weeks and achieved SVR12. The other 8 patients (14.8%) discontinued this treatment before 24 weeks due to adverse events. Of these 8 patients, 5 and 3 patients did and did not achieve SVR12, respectively. Finally, 51 of 54 (94.4%) patients achieved SVR12. Conclusion. Treatment with DCV and ASV after screening for HCV NS5A RAVs by PCR invader assay is effective and safe in the treatment of real-world HCV genotype 1-infected patients in Japan.

Sustained Virologic Response at 24 Weeks after the End of Treatment Is a Better Predictor for Treatment Outcome in Real-World HCV-Infected Patients Treated by HCV NS3/4A Protease Inhibitors with Peginterferon plus Ribavirin.

BACKGROUND: Direct-acting antiviral agents against HCV with or without peginterferon plus ribavirin result in higher eradication rates of HCV and shorter treatment duration. We examined which is better for predicting persistent virologic response, the assessment of serum HCV RNA at 12 or 24 weeks after the end of treatment for predicting sustained virologic response (SVR12 or SVR24, respectively) in patients treated by HCV NS3/4A protease inhibitors with peginterferon plus ribavirin. METHODS: In all, 149 Japanese patients infected with HCV genotype 1b treated by peginterferon plus ribavirin with telaprevir or simeprevir were retrospectively analyzed: 59 and 90 patients were treated with telaprevir- and simeprevir-including regimens, respectively. HCV RNA was measured by TaqMan HCV Test, version 2.0, real-time PCR assay. SVR12 or SVR24, respectively, was defined as HCV RNA negativity at 12 or 24 weeks after ending treatment. RESULTS: Total SVR rates were 78.0% and 66.7% in the telaprevir and simeprevir groups, respectively. In the telaprevir group, all 46 patients with SVR12 finally achieved SVR24. In the simeprevir group, 60 (93.8%) of the total 64 patients with SVR12 achieved SVR24, with the other 4 patients all being previous-treatment relapsers. CONCLUSIONS: SVR12 was suitable for predicting persistent virologic response in almost all cases. In simeprevir-including regimens, SVR12 could not always predict persistent virologic response. Clinicians should use SVR24 for predicting treatment outcome in the use of HCV NS3/4A protease inhibitors with peginterferon plus ribavirin for any group of real-world patients chronically infected with HCV.

The sirtuin inhibitor sirtinol inhibits hepatitis A virus (HAV) replication by inhibiting HAV internal ribosomal entry site activity.

Epigenetics plays a role in the regulation of gene expression. Epigenetic changes control gene expression at the transcriptional level. Our previous study suggested that the La protein, which is mainly localized in the nucleus, was associated with hepatitis A virus (HAV) internal ribosomal entry site (IRES)-mediated translation and HAV replication. The aim of this study was to investigate whether epigenetic compounds have effects on HAV IRES-mediated translation and HAV replication. Sirtinol, a sirtuin inhibitor, inhibited HAV IRES-mediated translation in COS7-HAV-IRES cells. Treatment with 10 µM sirtinol resulted in a significant reduction in the intracellular RNA levels of HAV HA11-1299 genotype IIIA in Huh7 cells. Epigenetic treatment with a sirtuin inhibitor may represent a new treatment option for HAV infection. In conclusion, epigenetic control was involved in HAV IRES-dependent translation and HAV replication. Special attention should also be paid to underlying viral diseases in the clinical use of epigenetic treatments for malignancies.

Association between hepatitis B virus and MHC class I polypeptide-related chain A in human hepatocytes derived from human-mouse chimeric mouse liver.

Due to the lack of efficient hepatitis B virus (HBV) infection systems, progress in understanding the role of innate immunity in HBV infection has remained challenging. Here we used human hepatocytes from a humanized severe combined immunodeficiency albumin promoter/enhancer driven-urokinase-type plasminogen activator mouse model for HBV infection. HBV DNA levels in culture medium from these human hepatocytes were 4.8-5.7 log IU/mL between day 16 and day 66 post-infection by HBV genotype C inoculum. HBV surface antigen (HBsAg) was also detected by chemiluminescent immunoassay from day 7 to day 66 post-infection. Western blot analysis revealed that major histocompatibility complex class I-related chain A (MICA), which plays a role in the innate immune system, was induced in HBV-infected human hepatocytes 27 days after infection compared with the uninfected control. MICA was reduced at day 62 and undetectable at day 90. Of interest, MICA expression by human hepatocytes increased after HBV infection and decreased before HBsAg loss. Human hepatocytes derived from chimeric mice with hepatocyte-humanized liver could support HBV genome replication. Further studies of the association between HBV replication and MICA induction should be conducted.