HBV with precore and basal core promoter mutations exhibits a high replication phenotype and causes ER stress-mediated cell death in humanized liver chimeric mice.

BACKGROUND AND AIMS: Mutations within the precore (PC) and basal core promoter (BCP) regions of the HBV genome are associated with fulminant hepatitis and HBV reactivation. These mutations may enhance viral replication, but little is known about whether they directly induce damage to the liver. We investigated mechanisms of direct cytopathic effects induced by the infection with PC/BCP mutants in the absence of immune response in vitro and in vivo . APPROACH AND RESULTS: Mice with humanized livers and hepatocytes derived from humanized mice were infected with either wild-type or mutant-type PC/BCP HBV, and the HBV replication and human hepatocyte damage were evaluated. HBV proliferated vigorously in mice with PC/BCP-mutant infection, and the severe loss of human hepatocytes with a slight human ALT elevation subsequently occurred only in PC/BCP mutant mice. In PC/BCP mutant infection, the accumulation of HBsAg in humanized livers colocalized with the endoplasmic reticulum, leading to apoptosis through unfolded protein response in HBV-infected hepatocytes. RNA-sequencing revealed the molecular characteristics of the phenotype of PC/BCP mutant infection in a humanized mouse model. Reduced ALT elevation and higher HBV DNA levels in this model are consistent with characteristics of HBV reactivation, indicating that the hepatocyte damage in this model might mimic HBV reactivation followed by hepatocyte damage under immunosuppressive conditions. CONCLUSION: PC and BCP mutations were associated with enhanced viral replication and cell death induced by ER stress using HBV infection models. These mutations might be associated with liver damage in patients with fulminant hepatitis or HBV reactivation.

A novel cDNA-uPA/SCID/Rag2-/- /Jak3-/- mouse model for hepatitis virus infection and reconstruction of human immune system.

Although human hepatocyte-transplanted immunodeficient mice support infection with hepatitis viruses, these mice fail to develop viral hepatitis due to the lack of an adaptive immune system. In this study, we generated new immunodeficiency cDNA-urokinase-type plasminogen activator (uPA)/SCID/Rag2-/- /Jak3-/- mice and established a mouse model with both a humanized liver and immune system. Transplantation of human hepatocytes with human leukocyte antigen (HLA)-A24 resulted in establishment of a highly replaced liver in cDNA-uPA/SCID/Rag2-/- /Jak3-/- mice. These mice were successfully infected with hepatitis B virus (HBV) and hepatitis C virus (HCV) for a prolonged period and facilitate analysis of the effect of anti-HCV drugs. Administration of peripheral blood mononuclear cells (PBMCs) obtained from an HLA-A24 donor resulted in establishment of 22.6%-81.3% human CD45-positive mononuclear cell chimerism in liver-infiltrating cells without causing graft-versus-host disease in cDNA-uPA/SCID/Rag2-/- /Jak3-/- mice without human hepatocyte transplantation. When mice were transplanted with human hepatocytes and then administered HLA-A24-positive human PBMCs, an alloimmune response between transplanted human hepatocytes and PBMCs occurred, with production of transplanted hepatocyte-specific anti-HLA antibody. In conclusion, we succeeded in establishing a humanized liver/immune system characterized by an allo-reaction between transplanted human immune cells and human liver using a novel cDNA-uPA/SCID/Rag2-/- /Jak3-/- mouse. This mouse model can be used to generate a chronic hepatitis mouse model with a human immune system with application not only to hepatitis virus virology but also to investigation of the pathology of post-transplantation liver rejection.

The Analysis of Muscle Volume Measured by Bioelectrical Impedance in Patients with Hepatocellular Carcinoma Treated with First-Line Atezolizumab plus Bevacizumab Combination Therapy or First-Line Lenvatinib.

INTRODUCTION: Measurements of body composition, such as the skeletal muscle index (SMI), are useful for predicting prognosis in hepatocellular carcinoma (HCC). This study aimed to analyze the relationship between skeletal muscle changes during therapy with atezolizumab plus bevacizumab (Atezo + Beva) or lenvatinib (Len) and the association between SMI and prognosis. METHODS: Patients with advanced HCC and Child-Pugh A status received Atezo + Beva or Len as first-line systemic chemotherapy. We assessed prognosis and body composition obtained by bioelectrical impedance analysis. RESULTS: A total of 109 patients received treatment (Atezo + Beva, n = 47; Len, n = 62). During treatment, the arm SMI was reduced in the Len group and maintained in the Atezo + Beva group. The extracellular water to total body water ratio (ECW/TBW) increased significantly in both groups during treatment. In the Atezo + Beva group, no factor was associated with prognosis. Multivariate analysis showed that in the Len group, the arm SMI (hazard ratio [HR], 0.5; 95% CI: 0.26-0.89; p = 0.02), ECW/TBW (HR: 2.7; 95% CI: 1.21-6.01; p = 0.01), and Child-Pugh score (HR: 2.3; 95% CI: 1.31-6.13; p = 0.004) were associated with progression-free survival. CONCLUSION: Assessing body composition with BIA before Atezo + Beva and Len treatment may be useful.

Correlation between serum pro-inflammatory cytokine levels and the prognosis of the patients with acute liver failure.

BACKGROUND AND AIM: The prognosis of acute liver failure (ALF) remains poor, and liver transplantation is an alternative treatment option. Assessing the prognosis of ALF is important in determining treatment strategies. Here, we investigated clinical factors including serum pro-inflammatory cytokine levels that are associated with the prognosis of ALF. METHODS: Sixty-six patients who developed ALF were enrolled in this study. Serum concentrations of 12 pro-inflammatory cytokines were measured on admission. The prognosis and factors associated with survival and development of hepatic coma were analyzed. RESULTS: Of 66 patients, 4 patients underwent liver transplantation, and 49 patients were rescued without liver transplantation, while the remaining 13 patients died. Serum concentrations of interleukin (IL)-1ß, IL-4, IL-6, IL-8, IL-13, TNF, IFN -γ, IP-10, and G-CSF were significantly elevated in ALF patients. IL-4 and IL-8 levels were higher in patients who underwent liver transplantation or died than in rescued patients. Multivariable analysis identified age ≥ 55 years and IL-4 ≥ 1.2 pg/mL on admission as independent factors for mortality. Serum IL-8 levels were higher in patients with hepatic coma, and prothrombin-international normalized ratio ≥ 3.5 and IL-8 ≥ 77.2 pg/mL on admission were associated with development of hepatic coma after admission. CONCLUSION: Serum levels of several pro-inflammatory cytokines were elevated in ALF patients. IL-4 and IL-8 were correlated with survival and development of hepatic coma after admission, respectively. Measurement of serum pro-inflammatory cytokines seems to be useful for the management of ALF.

The presence of vessels encapsulating tumor clusters is associated with an immunosuppressive tumor microenvironment in hepatocellular carcinoma.

Recently, a distinct vascular pattern in hepatocellular carcinoma (HCC) called vessels encapsulating tumor-forming clusters (VETC) has received attention because of its association with poor prognosis. However, little is known about the mechanism by which VETC promotes an aggressive phenotype at the molecular level. In our study, the association between differences in stepwise signal intensity in the HB phase and molecular subtypes and somatic mutations associated with the immune microenvironment were investigated using the International Cancer Genome Consortium (ICGC) cohort (66 patients). To our knowledge, this is the first study to analyze the molecular patterns of VETC using RNA-Seq data. The VETC+ HCC group showed significantly lower overall survival and higher cumulative incidence of extrahepatic metastasis after curative hepatic resection than the VETC- HCC group. The VETC+ group exhibited molecular features indicative of lower immune activation than the VETC- group, suggesting that tumor cells in the VETC+ group were more likely to escape from the immune response, which could lead to the shorter OS (Overall survival) and higher risk of metastasis. On the other hand, gene expression levels of fibroblast growth factor receptors were upregulated in VETC+ HCC, suggesting that VETC+ HCC might benefit from lenvatinib treatment. Our results demonstrate that VETC+ HCC was associated with the suppression of tumor immune responses at the molecular level.

Hepatic venous pressure gradient after balloon-occluded retrograde transvenous obliteration and liver stiffness measurement predict the prognosis of patients with gastric varices.

BACKGROUND: Balloon-occluded retrograde transvenous obliteration (BRTO) is a treatment option for patients with gastric varices (GVs). This study aimed to clarify the clinical significance of portal hypertension estimated by the hepatic venous pressure gradient (HVPG), subsequent exacerbation of esophageal varices (EVs), and prognosis of patients who underwent BRTO for GVs. METHODS: Thirty-six patients with GVs treated with BRTO were enrolled in this study, and their HVPG was measured before (pre-HVPG) and on the day after BRTO (post-HVPG). After BRTO, patients were followed-up for a median interval of 24.5 (3-140) months. Clinical factors related to EVs exacerbation and prognosis after BRTO were retrospectively analyzed. RESULTS: Post-HVPG increased compared to pre-HVPG in 21 out of 36 patients (58%), and post-HVPG was overall significantly higher compared to pre-HVPG (P = 0.009). During the observation period, 19 patients (53%) developed EVs exacerbation, and the cumulative EVs exacerbation rates at 1, 3 and 5 years after BRTO were 27%, 67%, and 73%, respectively. Pre-HVPG was not related to EVs exacerbation, although elevation of post-HVPG to ≥ 13 mmHg (P < 0.01) and high level of serum aspartate aminotransferase (P < 0.05) were significant independent risk factors for EVs exacerbation after BRTO. Fourteen patients (38.9%) died during the observation period. An elevated value of liver stiffness measurement (LSM) of ≥ 21 kPa was a significant independent risk factor for poor prognosis after BRTO (P < 0.05). CONCLUSIONS: HVPG increases after BRTO. HVPG after BRTO has greater predictive ability for subsequent EVs exacerbation than HVPG before BRTO. LSM is a potential prognostic parameter in patients who undergo BRTO.

Infection courses, virological features and IFN-α responses of HBV genotypes in cell culture and animal models.

BACKGROUND & AIMS: HBV consists of 9 major genotypes (A to I), 1 minor strain (designated J) and multiple subtypes, which may be associated with different clinical characteristics. As only cell lines expressing genotype D3 have been established, herein, we aimed to establish stable cell lines producing high-titer cell culture-generated HBV (HBVcc) of different genotypes and to explore their infectivity, virological features and responses to treatment. METHODS: Stable cell lines producing high titers of HBV genotype A2, B2, C1, E, F1b and H were generated by transfecting plasmids containing a replication-competent 1.3x length HBV genome and an antibiotic marker into HepG2 cells that can support HBV replication. Clones with the highest levels of HBV DNA and/or HBeAg were selected and expanded for large-scale purification of HBVcc. HBVcc of different genotypes were tested in cells and a humanized chimeric mouse model. RESULTS: HBVcc genotypes were infectious in mouse-passaged primary human hepatocytes (PXB cells) and responded differently to human interferon (IFN)-α with variable kinetics of reduction in HBV DNA, HBeAg and HBsAg. HBVcc of all genotypes were infectious in humanized chimeric mice but with variable kinetics of viremia and viral antigen production. Treatment of infected mice with human IFN-α resulted in modest and variable reductions of viremia and viral antigenemia. HBVcc passaged in humanized chimeric mice (HBVmp) infected PXB cells much more efficiently than that of the original HBVcc viral stock. CONCLUSIONS: Herein, we generated stable cell lines producing HBV of various genotypes that are infectious in vitro and in vivo. We observe genotype-associated variations in viral antigen production, infection kinetics and responses to human IFN-α treatment in these models. LAY SUMMARY: Stable cell lines producing high-titer cell culture-generated hepatitis B virus (HBV) of various genotypes were established. HBV genotypes showed stable infectivity in both in vitro and in vivo models, which are valuable tools for antiviral development.

Novel drug resistance-associated substitutions against pibrentasvir emerged in genotype 1b hepatitis C virus-infected human hepatocyte transplanted mice.

Combination therapy with glecaprevir and pibrentasvir (PIB) has high efficacy for patients with hepatitis C virus (HCV) infection except among those who experienced NS5A-P32 deletion (del) mutation during prior DAA treatment failure. However, some patients fail to achieve SVR through combination treatment even in the absence of NS5A-P32del. We analyzed emergence of NS5A resistance-associated substitutions (RASs) against PIB using HCV-infected mice. Male human hepatocyte transplanted mice were infected with genotype 1b wild-type HCV. Mice were treated with PIB, resulting in a transient decrease in serum HCV RNA levels but followed by relapse during the treatment. Direct sequence analysis showed emergences of various mutations in the NS5A region, including L31V/P32del, L31F/P32del/Y93H, NS5A-P29del/Y85C, and NS5A-F37Y. PIB was less effective in mice with NS5A-F37Y mutations compared to mice with wild-type HCV. NS5A-F37Y showed 5.4-fold resistance to PIB relative to wild-type based on analysis using HCV subgenomic replicon systems. The present in vivo and in vitro studies identified NS5A-F37Y as a novel RAS against PIB and showed the possibility of emergence of various NS5A RASs including P29del, P32del and F37Y following PIB treatment. These mutations might emerge and lead to failure to respond to DAA therapies including PIB-based regimens in chronic hepatitis C patients.

Serum PreS1 and HBsAg ratio reflects liver fibrosis and predicts the development of hepatocellular carcinoma in chronic hepatitis B patients.

While the preS1 region of the large hepatitis B surface protein plays an essential role in hepatitis B virus (HBV) infection, the effect of preS1 on liver fibrosis and hepatocarcinogenesis in chronic hepatitis B (CHB) patients is not well known. In this study, we measured serum preS1 levels by chemiluminescent immunoassay technology in 690 CHB patients and evaluated the correlation between serum preS1 levels and HBV, liver function markers and liver inflammation, fibrosis assessed by histological findings. Predictive factors for hepatocellular carcinoma (HCC) development in patients who had no previous history of HCC at the time of preS1 level measurement were also analysed. Median hepatitis B surface antigen (HBsAg) and preS1 levels were 3.08 log IU/mL and 98 ng/mL, respectively. PreS1 values were significantly correlated with serum HBsAg (p <0.001), hepatitis B core-related antigen (HBcrAg) (p <0.001) and HBV DNA levels (p <0.01). PreS1 values were also significantly correlated with serum alanine aminotransferase levels (p <0.001) and were significantly higher in patients who had higher grading of liver inflammatory activity (p <0.05). HBsAg level was correlated, but preS1/HBsAg ratio reflected liver fibrosis staging more directly than HBsAg alone. Multivariate analysis identified age ≥53 years (hazard ratio [HR], 18.360 for <53 years; p = 0.021) and preS1/HBsAg ratio ≥0.12 (HR, 6.205 for <0.12; p = 0.040) as significant and independent factors for HCC development in CHB patients. The preS1/HBsAg ratio directly reflects liver fibrosis, and the ratio might be a predictive marker for HCC development in CHB patients.

Abatacept treatment for patients with severe acute hepatitis caused by hepatitis B virus infection-Pilot study.

Although glucocorticoids have been used for immunosuppression of patients with primary hepatitis B virus (HBV) infection-induced severe hepatitis, the treatment is associated with a high frequency of adverse events. We conducted a pilot study for evaluating the efficacy and safety of abatacept, a cytotoxic T lymphocyte antigen-4 immunoglobulin (CTLA4), for acute hepatitis B. Five patients with severe acute hepatitis B (prothrombin activity ≤ 60%) were treated for immunosuppression by abatacept. Four patients received abatacept concurrently with methylprednisolone, and another patient was treated with abatacept alone. Rapid decrease in serum alanine aminotransferase levels, increase in prothrombin activity and improvement of general condition were obtained in four out of five patients. The patient with the most severe hepatitis underwent liver transplantation due to exacerbation of hepatitis in spite of treatment with both abatacept and methylprednisolone. None of the patients developed significant adverse events associated with the use of abatacept. Hepatitis B surface antigen (HBsAg) became negative in all five patients. The effect of abatacept and methylprednisolone for severe hepatitis B was compared using a mouse model. Rapid reduction in mouse serum HBV DNA and human albumin levels and elevation of serum interferon-gamma and granzyme A levels were observed in HBV-infected human hepatocyte-transplanted immunodeficient mice that were administered human peripheral blood mononuclear cells. These hepatocyte injuries were inhibited to a greater extent by abatacept compared to methylprednisolone. Abatacept might be an effective therapy alternative to methylprednisolone to reduce acute massive liver damage for patients with severe acute hepatitis caused by HBV infection.

Increasing incidence of non-HBV- and non-HCV-related hepatocellular carcinoma: single-institution 20-year study.

BACKGROUND: We previously reported on the trends in the etiologies of hepatocellular carcinoma (HCC) diagnosed in patients between 1995 and 2009. The aims of our updated study were to evaluate the incidence, nonhepatitis B and nonhepatitis C viral (NBNC) etiologies, and clinical characteristics of HCCs occurring in patients between 1992 and 2018. METHODS: The study enrolled 2171 consecutive patients with HCC between 1992 and 2018. Their medical records were reviewed. The patients were divided into two groups, patients with early diagnoses from 1992 to 2009 and those with late diagnoses from 2010 to 2018. RESULTS: NBNC-HCC occurred in 514 patients (23.6%). The percentage of patients with HCC who had NBNC-HCC increased from 26.5% in 2009 to 46.3% in 2018. Patients with NBNC-HCC were older (median ages from 67 to 73 years). Type 2 diabetes mellitus (48.5-60.3%: P = 0.008), hypertension (48.5-57.4%: P = 0.047), and hyperlipidemia (39.2-53.8%: P = 0.001) increased significantly in recent years. The median FIB-4 index decreased (4.37-3.61: P = 0.026) and the median platelet count increased (15.1-17.9 × 104/µL: P = 0.013). Among the 514 patients with NBNC-HCC, 194 underwent hepatic resection for nonalcoholic steatohepatitis (NASH) (15%), alcoholic liver disease (ALD) (29%), and cryptogenic hepatitis (56%). Cirrhosis was detected in 72%, 39%, and 16% of patients with NASH, ALD, and cryptogenic hepatitis, respectively. The prevalence of cirrhosis in patients with NASH was significantly higher than the prevalence of cirrhosis in the other groups (P < 0.001). Overall, 70% of the non-malignant liver tissue of patients with NBNC-HCC was not involved with cirrhosis. On the other hand, the median FIB-4 index in patients with cryptogenic HCC was 2.56, which was a significantly lower value than those values in the other groups of patients. The FIB-4 index considered as one of useful screening of HCC. CONCLUSIONS: The prevalence of NBNC-HCC has increased rapidly even in a regional university hospital. Metabolic syndrome may be an important risk factor for HCC. HCC was also found in patients with non-cirrhotic livers. The FIB-4 index may be a useful screening method for HCC in patients with NBNC.

Ribavirin induces hepatitis C virus genome mutations in chronic hepatitis patients who failed to respond to prior daclatasvir plus asunaprevir therapy.

Ribavirin (RBV) induces nucleotide (nt) substitutions in hepatitis C virus (HCV) genome nonstructural (NS) regions. Although emergence of drug resistance-associated variants is associated with direct-acting antiviral treatment failure, the effect of RBV on genome substitutions in such patients is unknown. Genotype 1b HCV subgenomic replicon cells were treated with RBV for 120 hours. Six patients with chronic genotype 1b with HCV-infected patients who failed to respond to prior daclatasvir plus asunaprevir (DCV/ASV) therapy were treated with 12 weeks of sofosbuvir and ledipasvir plus RBV after 4 weeks of RBV monotherapy. RBV-induced genome mutations in the HCV NS region (nt3493-9301) in replicon cells and in patients during 4 weeks of RBV monotherapy were analyzed by deep sequencing. RBV-associated G-to-A and C-to-U transitions increased in a dose-dependent manner in HCV replicon cells after the RBV treatment. In patients with prior DCV/ASV treatment failures, the median serum HCV RNA level was 6.25 ± 0.31 log IU/mL at the start of RBV therapy and decreased significantly to 5.95 ± 0.4 log IU/mL (P = .03) after 4 weeks of RBV monotherapy. Although predominant HCV genome substitutions rates were similar between nontreatment and RBV-treatment periods (0.042 and 0.031 per base pair, respectively; P = .248), the frequencies of G-to-A and C-to-U transitions significantly increased after RBV monotherapy. These transitions were enriched, particularly within the HCV NS3 region in all patients. RBV treatment induces G-to-A and C-to-U transitions in the HCV genome even in chronic patients with hepatitis C with prior DCV/ASV treatment failures.

Impact of viral eradication by direct-acting antivirals on the risk of hepatocellular carcinoma development, prognosis, and portal hypertension in hepatitis C virus-related compensated cirrhosis patients.

AIM: We analyzed the impact of hepatitis C virus eradication by direct-acting antiviral (DAA) therapy on the risk of development of hepatocellular carcinoma (HCC), prognosis, and portal hypertension in patients with liver cirrhosis. METHODS: The rate of HCC development and overall survival after achievement of sustained virological response (SVR) in 173 DAA-treated compensated cirrhosis patients without HCC history were retrospectively compared with that of 125 cirrhosis patients who achieved SVR by interferon (IFN)-based therapy or that of 85 cirrhosis patients who failed to respond to anti-HCV therapy. Changes in esophagogastric varices (EGV) and incidence of portosystemic encephalopathy were analyzed in 87 consecutive cirrhosis patients. RESULTS: The cumulative HCC development rates at 1, 3, and 5 years were 2%, 7%, and 7% for the DAA-SVR group, significantly lower than the 3%, 7%, and 18% for the non-SVR group (log-rank, P < 0.001). The cumulative overall survival rates were also significantly improved in the DAA-SVR group compared to the non-SVR group (log-rank, P < 0.001). These rates were similar between DAA-SVR and IFN-SVR groups (P = 0.121 and 0.261, respectively). Esophagogastric varices were aggravated, and portosystemic encephalopathy occurred in a subset of cirrhosis patients who achieved SVR by DAA therapy. These events were more frequent in patients with large feeding vessels for EGV and portosystemic shunts at the time of SVR. CONCLUSION: Achievement of SVR by DAA therapy reduces the risk of HCC development and prolongs survival, similar to theresults achieved with IFN-based therapy, but portal hypertension is not immediately improved in compensated liver cirrhosis patients.

Real-world efficacy of sofosbuvir plus velpatasvir therapy for patients with hepatitis C virus-related decompensated cirrhosis.

AIM: Combination therapy with sofosbuvir (SOF) plus velpatasvir (VEL) is approved for patients with hepatitis C virus (HCV)-related decompensated cirrhosis. We analyzed the real-world efficacy of SOF/VEL therapy. METHODS: Thirty-three patients with HCV-related decompensated cirrhosis (25 and eight patients with Child B and C, respectively) were treated with SOF/VEL for 12 weeks. The HCV non-structural protein (NS)5A and NS5B drug resistance-associated substitutions (RASs) were determined by direct sequencing. RESULT: Thirty-two of 33 patients completed the treatment, but the remaining patient discontinued the therapy during third week of the treatment due to aggravation of hepatic encephalopathy. Serum HCV-RNA became negative during the treatment in all patients but relapsed after the end of therapy in five patients. In total, 28 out of 33 patients (85%) achieved sustained virological response 12 weeks following completion of treatment (SVR12). The SVR12 rate was 96% in patients with Child B, but significantly lower, at 50%, in patients with Child C (P < 0.05). In genotype 1b HCV-infected patients, all eight patients without baseline NS5A RASs, but only three of seven patients with RASs, achieved SVR12. Multivariate analysis identified Child B (odds ratio, 35.8 for Child C; P = 0.045) as an independent predictor of SVR12. Median serum albumin levels significantly increased only in patients who achieved SVR12. Child-Pugh scores improved in 16 of 28 patients (57%) following achievement of SVR12. CONCLUSION: The effect of SOF/VEL therapy is lower for patients with Child C. Improvement of hepatic function is expected after viral eradication with SOF/VEL therapy in patients with decompensated cirrhosis.

Efficacy of glecaprevir and pibrentasvir treatment for genotype 1b hepatitis C virus drug resistance-associated variants in humanized mice.

Combination therapy with glecaprevir (GLE) and pibrentasvir (PIB) has high efficacy for pan-genotypic hepatitis C virus (HCV)-infected patients. However, the efficacy for patients who acquired potent NS5A inhibitor resistance-associated variants (RAVs) as a result of failure to respond to previous direct-acting antiviral (DAA) therapies is unclear. We investigated the efficacy of GLE/PIB treatment for genotype 1b HCV strains containing RAVs using subgenomic replicon systems and human hepatocyte transplanted mice. Mice were injected with serum samples obtained from a DAA-naïve patient or daclatasvir plus asunaprevir (DCV/ASV) treatment failures including NS5A-L31M/Y93H, -P58S/A92K or -P32 deletion (P32del) RAVs, then treated with GLE/PIB. HCV was eliminated by GLE/PIB treatment in mice with wild-type and NS5A-L31M/Y93H but relapsed in mice with NS5A-P58S/A92K, followed by emergence of additional NS5A mutations after cessation of the treatment. In NS5A-P32del-infected mice, serum HCV RNA remained positive during the GLE/PIB treatment. NS5A-P58S/A92K showed 1.5-fold resistance to PIB relative to wild-type based on analysis using HCV subgenomic replicon systems. When mice were administered various proportions of HCV wild-type and P32del strains and treated with GLE/PIB, serum HCV RNA remained positive in mice with high frequencies of P32del. In these mice, the P32del was undetectable by deep sequencing before GLE/PIB treatment, but P32del strains relapsed after cessation of the GLE/PIB treatment. GLE/PIB is effective for wild-type and NS5A-L31M/Y93H HCV strains, but the effect seems to be low for P58S/A92K and NS5A-P32del RAVs. Although NS5A-P32del was not detected, the mutation may be present at low frequency in DCV/ASV treatment failures.

The impact of interferon-free direct-acting antivirals on clinical outcome after curative treatment for hepatitis C virus-associated hepatocellular carcinoma: Comparison with interferon-based therapy.

BACKGROUND AND AIM: To examine the effect on recurrence and survival of treatment by interferon (IFN)-free direct-acting antivirals (DAA) for patients with hepatitis C virus (HCV)-associated hepatocellular carcinoma (HCC) who underwent primary curative treatment. METHODS: This was a retrospective cohort study of 250 patients with HCV who had received curative treatment for primary HCC. As anti-HCV treatment after HCC treatment, 38 patients received IFN-free DAA therapy (DAA patients) and 94 received IFN-based therapy (IFN patients). The recurrence of HCC and overall survival of the patient groups were compared in a case-control study. RESULTS: The cumulative HCC recurrence rates at 1, 3, and 5 years were 5%, 39%, and 39% for DAA patients and 0%, 46%, and 62% for IFN patients, respectively (P = 0.370). Multivariate analysis of the HCC recurrence identified treatment responses (sustained virological response [SVR]: hazard ratio [HR] 2.237; P = 0.003) as an independent predictive factor. The cumulative overall survival rates at 3 and 5 years were 96%, 96% for DAA patients and 93%, 73% for IFN patients, respectively ( P = 0.163). Multivariate analysis identified treatment responses (SVR: HR 8.742; P < 0.001) as independent predictors of overall survival. Propensity score matching analysis showed no significant difference in HCC development rates and overall survival rates in the two groups. CONCLUSIONS: We found that SVR obtained after curative treatment for primary HCC suppressed recurrence and improved overall survival. And, IFN-free DAA therapy after curative treatment for primary HCC could predict improving overall survival and suppressed HCC recurrence.

Limitations of daclatasvir/asunaprevir plus beclabuvir treatment in cases of NS5A inhibitor treatment failure.

Combined daclatasvir (DCV)/asunaprevir (ASV) plus beclabuvir (BCV) treatment shows a high virological response for genotype 1b chronic hepatitis C patients. However, its efficacy for patients for whom previous direct-acting antiviral (DAA) therapy failed is not known. We analysed the efficacy of DCV/ASV/BCV treatment for HCV-infected mice and chronic hepatitis patients. Human hepatocyte chimaeric mice were injected with serum samples obtained from either a DAA-naïve patient or a DCV/ASV treatment failure and were then treated with DCV/ASV alone or in combination with BCV for 4 weeks. DCV/ASV treatment successfully eliminated the virus in DAA-naïve-patient HCV-infected mice. DCV/ASV treatment failure HCV-infected mice developed viral breakthrough during DCV/ASV treatment, with the emergence of NS5A-L31V/Y93H HCV resistance-associated variants (RAVs) being observed by direct sequencing. DCV/ASV/BCV treatment inhibited viral breakthrough in NS5A-L31V/Y93H-mutated HCV-infected mice, but HCV relapsed with the emergence of NS5B-P495S variants after the cessation of the treatment. The efficacy of the triple therapy was also analysed in HCV-infected patients; one DAA-naïve patient and four prior DAA treatment failures were treated with 12 weeks of DCV/ASV/BCV therapy. Sustained virological response was achieved in a DAA-naïve patient and one of the DCV/ASV treatment failures through DCV/ASV/BCV therapy; however, HCV relapse occurred in the other patients with prior DCV/ASV and/or sofosbuvir/ledipasvir treatment failures. DCV/ASV/BCV therapy seems to have limited efficacy for patients with NS5A RAVs for whom prior DAA treatment has failed.

Prevalence of NS5A resistance associated variants in NS5A inhibitor treatment failures and an effective treatment for NS5A-P32 deleted hepatitis C virus in humanized mice.

Patients with chronic hepatitis C virus (HCV) infection who have failed to respond to direct-acting antiviral (DAA) treatment often acquire drug resistance-associated variants (RAVs). The NS5A-P32 deletion (P32del) RAV confers potent resistance to NS5A inhibitors; therefore, patients who acquire this deletion are likely to fail to respond to DAA re-treatment. We investigated the prevalence of N55A-P32del in patients who failed to respond to prior NS5A inhibitor treatment using direct sequencing and analyzed the efficacy of DAA combination treatment in the presence of NS5A-P32del RAVs using human hepatocyte transplanted mice. NS5A-P32del was detected in one of 23 (4.3%) patients who had failed to respond to prior NS5A inhibitor treatment. Although four weeks of NS3/4A protease inhibitor glecaprevir plus NS5A inhibitor pibrentasvir treatment effectively suppressed HCV replication in wild-type HCV-infected mice, serum HCV RNA never became negative in P32del HCV-infected mice. When P32del HCV-infected mice were treated with four weeks of glecaprevir plus pibrentasvir combined with the NS5B polymerase inhibitor sofosbuvir, serum HCV RNA became negative, and the virus was eliminated from the liver in three out of four mice. We conclude that the combination of sofosbuvir and glecaprevir plus pibrentasvir may be an effective new treatment option for patients with NS5A-P32del.

Efficacy and safety of edoxaban for treatment of portal vein thrombosis following danaparoid sodium in patients with liver cirrhosis.

AIM: To compare the efficacy and safety of edoxaban and warfarin for treatment of portal vein thrombosis (PVT) following danaparoid sodium in patients with liver cirrhosis. METHODS: Fifty cirrhotic patients with PVT treated initially for 2 weeks with danaparoid sodium were enrolled in this retrospective cohort study. Treatment was later switched to either edoxaban (n = 20) or warfarin (n = 30). We compared the efficacy and safety of edoxaban and warfarin for up to 6 months. The PVT volume was measured by dynamic computed tomography before treatment, at 2 weeks, and at 1, 3, and 6 months. RESULTS: There were no significant differences in the clinical characteristics of patients in the two groups. Treatment with edoxaban reduced the volume of PVT from 1.42 cm3 at 2 weeks to 0.42 cm3 at 6 months, and prevented exacerbation of PVT at 6 months after treatment with danaparoid sodium (P = 0.016). In contrast, treatment with warfarin resulted in increased PVT volume from 1.73 cm3 at 2 weeks to 2.85 cm3 at 6 months, despite the control of the international normalized ratio in 57% of the patients (P = 0.005). Multivariate regression analysis identified edoxaban therapy as the single significant and independent determinant of PVT reduction at 6 months (P = 0.0014, hazard ratio 6.400). Clinically significant gastrointestinal bleeding was encountered in 3 of 20 (15%) patients of the edoxaban group and 2 of 30 (7%) of the warfarin group (P = 0.335). CONCLUSION: Edoxaban following danaparoid sodium is an effective anticoagulant and could be potentially considered as one of the treatment options for PVT in cirrhotic patients.

Clinical outcomes of stereotactic body radiotherapy for elderly patients with hepatocellular carcinoma.

AIM: To evaluate the safety and efficacy of stereotactic body radiotherapy (SBRT) for the treatment of hepatocellular carcinoma (HCC) in elderly patients. METHODS: From 2008 to 2015, 117 patients with HCC (≤3 nodules, ≤30 mm in diameter, Child-Pugh score ≤7, and no vascular or extracellular metastasis) were treated with SBRT at our hospital. We evaluated overall survival (OS), disease-free survival (DFS), local control, and adverse events. Patients were stratified according to age 75 years and older (elderly group, n = 54) and age younger than 75 years (young group, n = 63). RESULTS: The median OS in the elderly group was not significantly different from that in the young group (52 months vs. not reached, P = 0.27). The 1-, 2-, and 3-year OS rates were 96.2%, 77.6%, and 63.9%, respectively, in the elderly group, and 96.8%, 84.8%, and 67.7%, respectively, in the young group. The median DFS in the elderly group was significantly shorter than that in the young group (13 vs. 25 months, respectively; P = 0.03). The 1-, 2-, and 3-year DFS rates were 50.6%, 30.4%, and 26.6%, respectively, in the elderly group and 66.5%, 50.7%, and 45.3%, respectively, in the young group. The 3-year local tumor control rate in the elderly group was 98.1%, and that in the young group was 98.4% (P = 0.83). There was no difference between groups in the incidence of any adverse events. CONCLUSIONS: Stereotactic body radiotherapy can be effective and safe for the treatment of HCC in elderly patients.