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Background and aimsEpitranscriptomic modification of RNA has emerged as the most prevalent form of regulation of gene expression that affects development, differentiation, metabolism, viral infections, and most notably cancer. We have previously shown that hepatitis B virus (HBV) transcripts are modified by N6 methyladenosine (m6 A) addition. HBV also affects m6 A modification of several host RNAs, including phosphatase and tensin homolog (PTEN), a well-known tumor suppressor. PTEN plays a critical role in antiviral innate immunity and the development of hepatocellular carcinoma (HCC). Reports have shown that PTEN controlled interferon regulatory factor 3 (IRF-3) nuclear localization by negative phosphorylation of IRF-3 at Ser97, and PTEN reduced carcinogenesis by inhibiting the phosphatidylinositol-3-kinase (PI3K)/AKT pathway.Approach and resultsHere, we show that HBV significantly increases the m6 A modification of PTEN RNA, which contributes to its instability with a corresponding decrease in PTEN protein levels. This is reversed in cells in which the expression of m6 A methyltransferases is silenced. PTEN expression directly increases activated IRF-3 nuclear import and subsequent interferon synthesis. In the absence of PTEN, IRF-3 dephosphorylation at the Ser97 site is decreased and interferon synthesis is crippled. In chronic HBV patient biopsy samples, m6 A-modified PTEN mRNA levels were uniformly up-regulated with a concomitant decrease of PTEN mRNA levels. HBV gene expression also activated the PI3K/AKT pathway by regulating PTEN mRNA stability in HCC cell lines.ConclusionsThe m6 A epitranscriptomic regulation of PTEN by HBV affects innate immunity by inhibiting IRF-3 nuclear import and the development of HCC by activating the PI3K/AKT pathway. Our studies collectively provide new insights into the mechanisms of HBV-directed immune evasion and HBV-associated hepatocarcinogenesis through m6 A modification of the host PTEN mRNAs.

Direct-acting antiviral (DAA) therapy, recently approved for patients with decompensated cirrhosis (DC) secondary to hepatitis C virus (HCV), is associated with improved hepatic function. We analyzed trends in liver transplant (LT) wait-listing (WL) to explore potential impact of effective medical therapy on WL registration. This is a cohort study using the Scientific Registry of Transplant Recipients database from 2003 to 2015. A total of 47,591 adults wait-listed for LT from HCV, hepatitis B virus (HBV), and nonalcoholic steatohepatitis (NASH) were identified. LT indication was defined as DC if the Model for End-Stage Liver Disease (MELD) at WL was ≥15 or hepatocellular carcinoma (HCC). Era of listing was divided into interferon (IFN; 2003-2010), protease inhibitor (PI; 2011-2013), and direct-acting antiviral (DAA; 2014-2015). Annual standardized incidence rates of WL were analyzed using Poisson regression. Adjusted incidences of LT WL for DC in HCV patients decreased by 5% in the PI era (P = 0.004) and 32% in the DAA era (P < 0.001) compared to the IFN era. Listing for DC in HBV also decreased in the PI (-17%; P = 0.002) and DAA eras (-24%; P < 0.001). Conversely, WL for DC in NASH increased by 41% in the PI era (P < 0.001) and 81% in the DAA era (P < 0.001). WL for HCC in both the HCV and NASH populations increased in both the PI and DAA eras (P < 0.001 for all) whereas HCC WL in HBV remained stable (P > 0.05 for all).ConclusionThe rate of LT WL for HCV complicated by DC has decreased by over 30% in the era of DAA therapy. Further reductions in WL are anticipated with increased testing, linkage to care, and access to DAA therapy. (Hepatology 2017;65:804-812).

UnlabelledDiabetes is associated with liver disease progression and increased hepatocellular carcinoma risk, but factors associated with diabetes in patients with chronic hepatitis B virus (HBV) infection in North America are unknown. We aimed to determine factors predictive of diabetes and impaired fasting glucose (IFG) in a large HBV-infected multiethnic cohort. Adults with chronic HBV not receiving antiviral therapy were enrolled from 21 centers in North America. Diabetes was defined by history/medication use or fasting glucose≥126 mg/dL and IFG as fasting glucose 100-125 mg/dL. Of 882 patients included, 47.2% were female, 71.3% Asian, 83.7% foreign born, median age was 44 years, and median body mass index BMI 24.3 kg/m2. In this cohort, 26.0% were hepatitis B envelope antigen (HBeAg) positive, 43.9% had HBV DNA≥20,000 IU/mL, and 26.7% alanine aminotransferase (ALT)≥2× upper limit of normal (≥40 U/L women, ≥60 U/L men). Overall, 12.5% had diabetes and 7.8% IFG. The combined prevalence of diabetes or IFG was highest among blacks (36.7%) and those either born in the United States/Canada or foreign born with migration>20 years ago (25.5%). Obesity (odds ratio [OR]: 2.13), hyperlipidemia (OR, 4.13), hypertension (OR, 3.67), high ALT level (OR, 1.86), and family history of diabetes (OR, 3.43) were associated with diabetes. Factors associated with IFG were obesity (OR, 4.13) and hypertension (OR, 3.27), but also HBeAg positivity (OR, 0.39). Recent migration was negatively associated with diabetes among non-Asians (OR, 0.30).ConclusionsDiabetes is more prevalent in HBV-infected North American adults than the general population and is associated with known metabolic risk factors and liver damage, as determined by ALT levels. Among the foreign born, longer duration of North America residence predicted diabetes risk in non-Asians. These results highlight the opportunities for interventions to prevent diabetes especially among at-risk ethnic groups with HBV.

UnlabelledReactivation of hepatitis B in the context of immunosuppressive therapy may be severe and potentially fatal. The US Food and Drug Administration has recently drawn attention to the potentially fatal risk of hepatitis B reactivation in patients receiving the anti-CD20 agents ofatumumab or rituximab. This action focuses attention on the broader issue of hepatitis B virus reactivation, which may occur with a wide variety of immunosuppressive therapies in benign or malignant disease. This article summarizes the data behind this issue. These data support the recommendation that all patients undergoing chemotherapy, immunosuppressive therapy, hematopoietic stem cell transplantation, or solid organ transplantation be screened for active or prior hepatitis B viral infection by testing for hepatitis B surface antigen and the antibody to hepatitis B core antigen in serum. Those who are found to be hepatitis B surface antigen-positive should start appropriate antiviral therapy to prevent reactivation. Additionally, even those who have recovered from hepatitis B will benefit from antiviral therapy in certain circumstances because of the risks associated with a form of hepatitis B virus reactivation referred to as "reverse seroconversion." There remain many uncertain areas that warrant further study, and further advances will benefit from close interactions between various medical specialties, regulatory agencies, and researchers.ConclusionsThere is good evidence to support routine screening of all patients for hepatitis B prior to undergoing chemotherapy or immunosuppressive treatment; use of prompt antiviral treatment appears to diminish the risk of severe or fatal reactivation of hepatitis B.