Prevention of hepatitis B virus-associated liver diseases by antiviral therapy

Hepatitis B virus (HBV) is a major cause of acute and chronic hepatitis, cirrhosis and hepatocellular carcinoma, particularly in Asia–Pacific countries. The major complications in HBV carriers are hepatocellular carcinoma (HCC), liver failure and esophageal varices following the progression to cirrhosis, while some develop HCC without cirrhosis. The progression to liver fibrosis and these other complications could be prevented by treatment with nucleos(t)ide analogues (NUCs); however, NUCs must be continuously administered for a long time. Peginterferon could lead to HBV surface antigen loss. It is difficult to use peginterferon in HBV-infected patients with decompensated cirrhosis. Acute liver failure due to HBV infection and acute exacerbation of chronic hepatitis B could be treated by NUCs. Universal vaccination programs against HBV could prevent new HBV infections globally. Here, we review the currently available treatments for HBV infection.     

Common clinicopathological features of the patients with chronic hepatitis B virus infection who developed hepatocellular carcinoma after seroconversion to anti-HBs--a consideration of the pathogenesis of HBV-induced hepatocellular carcinoma and a strategy to inhibit it

BACKGROUND/AIMS: The incidence of hepatocellular carcinoma among patients who have seroconverted to anti-hepatitis B surface antigen (anti-HBs) remains controversial. METHODOLOGY: We report four patients with chronic hepatitis B virus (HBV) infection who had cleared HBsAg and had developed anti-HBs at a later time, but who developed hepatocellular carcinoma (HCC) eventually. RESULTS: The common clinicopathological characteristics of the four patients were: An established diagnosis of precirrhosis or liver cirrhosis more than a decade previously, a long-standing normalization or stabilization at a low level of ALT values due to undetectable HBV DNA by the Amplicore Monitor assay, and a marked reduction of the fibrosis level in the non-tumorous liver obtained at HCC surgery or autopsy compared to the previous histology more than a decade previously. There was no fibrosis in the needle biopsy specimen from one patient. CONCLUSIONS: Our findings suggest that HCC due to HBV can occur in the serologically-cured stage if progression to pre-cirrhosis or cirrhosis already has occurred, where the fibrosis level has improved considerably because of the long-term absence of active HBV viremia and inflammation. Active medical intervention to prevent liver cirrhosis for chronic hepatitis B may have an important role in the inhibition of HCC in patients with chronic hepatitis B.     

Does antiviral therapy for hepatitis B and C prevent hepatocellular carcinoma?

Approximately 75% to 80% of hepatocellular carcinomas (HCC) worldwide are attributed to chronic hepatitis B virus (HBV) and chronic hepatitis C virus (HCV) infection. Thus, effective prevention of HBV and HCV infection and progression from acute HBV and HCV infection to chronic hepatitis, cirrhosis and HCC might prevent as many as 450,000 deaths from HCC each year. The most effective approach to preventing HCC is to prevent HBV and HCV infection through vaccination. Indeed HBV vaccine is the first vaccine demonstrated to prevent cancers. However, a vaccine for HCV is not available and for persons who are chronically infected with HBV or HCV, antiviral therapy is the only option for preventing HCC. Direct evidence supporting a benefit of antiviral therapy on the prevention of HCC has been shown in a few randomized controlled trials. There is abundant evidence that antiviral therapy, in patients with long-term virological response, can improve liver histology, providing indirect support that antiviral therapy may prevent HCC by slowing progression of liver disease and possibly even reversing liver damage. Nevertheless, the risk of HCC remains in patients with chronic HBV or chronic HCV infection if treatment is initiated after cirrhosis is established. These data indicate that treatment might be of greater benefit if instituted earlier in the course of chronic hepatitis B or C. Safer, more effective, and more affordable antiviral therapies are needed for both hepatitis B and hepatitis C so more patients can benefit from treatment and more HCCs can be prevented.     

Abnormal expression of HSP gp96 associated with HBV replication in human hepatocellular carcinoma

BACKGROUND: Heat shock protein (HSP) gp96 is a member of the HSP90 family and presumably overexpresses as a result of stimulation by mutated or abnormal proteins. Its abnormal expression correlates with carcinogenesis, progression and prognosis of hepatocellular carcinoma (HCC). In this study, we investigated the pathological characteristics of liver gp96 expression and its relationship with hepatitis B virus (HBV) replication in HCC patients. METHODS: Tumor specimens were prospectively collected from 30 HCC patients undergoing liver resection. Total RNAs were extracted from HCC or their noncancerous tissues. The distribution of gp96 expression in hepatocytes was investigated by streptavidin peroxidase (S-P) immunohistochemistry and tissue HBV-DNA was detected by the in situ molecular hybridization technique. The association of gp96 expression with HBV replication, and the histopathological characteristics of HCC were analyzed. RESULTS: The gp96 was strongly expressed in HCC (73.3%, 22 of 30) and weakly (46.7%, 14 of 30) in non-cancerous tissues. The gp96 expression in HCC tissues was correlated with degree of tumor differentiation and tumor size, but not with tumor number (P>0.05). Immunohistochemical analysis showed that 17 of 19 HCC patients with HBVDNA -positive were strongly expressed for gp96, whereas only 5 of 11 patients with HBV-DNA-negative were positive for gp96. A significant difference was found between the two groups (89.5% vs. 45.5%, P<0.05). CONCLUSIONS: The abnormal expressions of HSP gp96 in HCC tissues are associated with HBV replication. This finding indicates that HBV infection plays an important role in the development of HCC.     

Immune suppression in chronic hepatitis B infection associated liver disease: A review

Hepatitis B virus(HBV) infection is one the leading risk factors for chronic hepatitis, liver fibrosis, cirrhosis and hepatocellular cancer(HCC), which are a major global health problem. A large number of clinical studies have shown that chronic HBV persistent infection causes the dysfunction of innate and adaptive immune response involving monocytes/macrophages, dendritic cells, natural killer(NK) cells, T cells. Among these immune cells, cell subsets with suppressive features have been recognized such as myeloid derived suppressive cells(MDSC),NK-reg, T-reg, which represent a critical regulatory system during liver fibrogenesis or tumourigenesis. However, the mechanisms that link HBVinduced immune dysfunction and HBV-related liver diseases are not understood.In this review we summarize the recent studies on innate and adaptive immune cell dysfunction in chronic HBV infection, liver fibrosis, cirrhosis, and HCC, and further discuss the potential mechanism of HBV-induced immunosuppressive cascade in HBV infection and consequences. It is hoped that this article will help ongoing research about the pathogenesis of HBV-related hepatic fibrosis and HBV-related HCC.     

High serum adiponectin correlates with advanced liver disease in patients with chronic hepatitis B virus infection

Purpose  Adiponectin possesses anti-inflammatory and insulin-sensitizing properties. Little is known about the role of adiponectin in hepatitis B-related liver disease. Methods  Serum adiponectin and hepatitis B viral factors were cross-sectionally assayed in 280 patients with chronic hepatitis B virus (HBV) infection including 120 patients with chronic HBV infection, 40 patients with cirrhosis, and 120 patients with hepatocellular carcinoma (HCC); 116 healthy adults were used as controls. The dynamics of serum adiponectin level was also studied longitudinally in 25 patients with hepatitis B e antigen (HBeAg) seroconversion (SC). Results  We found that serum adiponectin level in patients with chronic HBV infection was similar to that in healthy controls and was significantly lower than patients with cirrhosis and HCC. In univariate analysis, high serum adiponectin level significantly correlated with the presence of HBV-related cirrhosis or HCC, abnormal serum ALT level, and HBV genotype C. Multivariate analysis revealed that high serum adiponectin level significantly correlated with the development of HCC. Serum adiponectin levels remained stationary in patients experiencing HBeAg SC. Conclusions  Our findings suggest that HBV infection itself does not affect adiponectin levels. Serum adiponectin level correlates with the progression of HBV-related liver diseases but not with the development of HBeAg SC.     

Pathogenesis of hepatitis B virus infection

Infection with hepatitis B virus (HBV) leads to a wide spectrum of clinical presentations ranging from an asymptomatic carrier state to self-limited acute or fulminant hepatitis to chronic hepatitis with progression to cirrhosis and hepatocellular carcinoma. Infection with HBV is one of the most common viral diseases affecting man. Both viral factors as well as the host immune response have been implicated in the pathogenesis and clinical outcome of HBV infection. In this review, we will discuss the impact of virus-host interactions for the pathogenesis of HBV infection and liver disease. These interactions include the relevance of naturally occurring viral variants for clinical disease, the role of virus-induced apoptosis for HBV-induced liver cell injury and the impact of antiviral immune responses for outcome of infection.     

Basal core-promoter mutant of hepatitis B virus and progression of liver disease in hepatitis B e antigen-negative chronic hepatitis B.

BACKGROUND/AIMS: The long-term outcomes in hepatitis B e antigen (HBeAg)-negative chronic hepatitis B are distinct from those in HBeAg-positive chronic hepatitis. However, the molecular virological factors that contribute to the progression of liver disease in this special clinical setting remain largely unknown. We thus investigated the association of hepatitis B virus (HBV) genotypes as well as precore/basal core-promoter mutations with the clinical and virological characteristics of patients with HBeAg-negative chronic hepatitis B in Taiwan. METHODS: HBV genotypes and sequences of precore and basal core-promoter regions of the HBV genome were determined in 174 HBeAg-negative chronic HBV infection patients including 62 inactive carriers and 112 with different stages of liver disease. RESULTS: HBV carriers with older age (> 50 years) (odds ratio, 9.09; 95% confidence interval (CI), 3.22-25, P < 0.001) and basal core-promoter mutant of HBV (odds ratio, 4.12; 95% CI, 1.41-12.03, P = 0.01) were associated with the development of liver cirrhosis and hepatocellular carcinoma (HCC). The gender-related risk factors associated with the development of liver cirrhosis and HCC were further analyzed, and basal core-promoter mutant was only associated with the development of liver cirrhosis and HCC in male carriers (odds ratio, 4.35; 95% CI, 1.30-14.52, P = 0.02). CONCLUSIONS: The risk of development of liver cirrhosis and HCC is significantly increased in patients with advanced age as well as with basal core-promoter mutant of HBV. In addition, basal core-promoter mutant might contribute to the gender difference of the progression of liver disease in HBeAg-negative chronic hepatitis B in Taiwan.     

乙型肝炎肝硬化抗病毒治疗的进展

乙型肝炎病毒（Hepatitis B virus,HBV）感染呈世界性流行, 目前HBV慢性感染是导致肝硬化及肝癌的主要原因,也是全球重要的健康问题。乙型肝炎肝硬化的发生、疾病进展、预后情况与血清HBV DNA水平密切相关,且有多项研究表明有效抑制HBV复制可以改善甚至逆转肝纤维化,降低肝硬化患者长期并发症发生的概率,改善预后,降低肝硬化及肝癌的发生。因而有效地抗病毒治疗对肝硬化患者尤为重要。目前主要抗病毒治疗药物为干扰素类和核苷酸类药物,且近年来在安全性及方案选择方面有了较大的研究进展。     

Occult hepatitis B virus infection is not associated with disease progression of chronic hepatitis C virus infection

AIM To clarify the prevalence of occult hepatitis B virus(HBV) infection(OBI) and the association between OBI and liver disease progression, defined as development of liver cirrhosis or hepatocellular carcinoma(HCC), worsening of Child-Pugh class, or mortality in cases of chronic hepatitis C virus(HCV) infection. METHODS This prospective cohort study enrolled 174 patients with chronic HCV infection(chronic hepatitis, n = 83; cirrhosis, n = 47; HCC, n = 44), and evaluated disease progression during a mean follow-up of 38.7 mo. OBI was defined as HBV DNA positivity in 2 or moredifferent viral genomic regions by nested polymerase chain reaction using 4 sets of primers in the S, C, P and X open reading frame of the HBV genome. RESULTS The overall OBI prevalence in chronic HCV patients at enrollment was 18.4%, with 16.9%, 25.5% and 13.6% in the chronic hepatitis C, liver cirrhosis and HCC groups, respectively(P = 0.845). During follow-up, 52 patients showed disease progression, which was independently associated with aspartate aminotransferase 40 IU/L, Child-Pugh score and sustained virologic response(SVR), but not with OBI positivity. In 136 patients who were not in the SVR state during the study period, OBI positivity was associated with neither disease progression, nor HCC development. CONCLUSION The prevalence of OBI in chronic HCV patients was 18.4%, and OBI was not associated with disease progression in South Koreans.     

Role of viral factors in the natural course and therapy of chronic hepatitis B

Hepatitis B virus (HBV) infection is a global health problem that causes a wide spectrum of liver disease, including acute or fulminant hepatitis, inactive carrier state, chronic hepatitis, cirrhosis, and hepatocellular carcinoma (HCC). The pathogenesis of hepatocyte damage associated with HBV is mainly through immune-mediated mechanisms. On the basis of the virus and host interactions, the natural history of HBV carriers who are infected in early life can be divided into four dynamic phases. The frequency, extent, and severity of hepatitis flares or acute exacerbation in the second immune clearance and/or fourth reactivation phase predict liver disease progression in HBV carriers. In the past decade, hepatitis B viral factors including serum HBV DNA level, genotype, and naturally occurring mutants predictive of clinical outcomes have been identified. The higher the serum HBV DNA level after the immune clearance phase, the higher the incidence of adverse outcomes over time. In addition, high viral load, genotype C, basal core promoter mutation, and pre-S deletion correlate with increased risk of cirrhosis and HCC development. As to the treatment of chronic hepatitis B, patients with high HBV DNA level and genotype C or D infection are shown to have a worse response to interferon therapy. In conclusion, serum HBV DNA level, genotype, and naturally occurring mutants are identified to influence liver disease progression and therapy of chronic hepatitis B. More investigations are needed to clarify the molecular mechanisms of the viral factors involved in the pathogenesis of each stage of liver disease and the response to antiviral treatments.     

Subgenotypes of hepatitis B virus genotype C do not correlate with disease progression of chronic hepatitis B in Taiwan.

BACKGROUND: Hepatitis B virus (HBV) genotype C (HBV/C) has two subgenotypes: HBV/Cs and Ce. The prevalence and clinical implications of subgenotype Cs and Ce in Taiwanese HBV carriers remain unknown. METHODS: Subgenotypes of HBV/C were determined in 242 Taiwanese HBV carriers with various stages of liver disease. The clinical as well as virologic features between patients with HBV/Cs and HBV/Ce infection were further compared. RESULTS: HBV/Ce was the predominant subgenotype in Taiwan. The prevalence of HBV/Ce was 93.6% in the inactive carriers group, 84.2% in chronic hepatitis patients, 81.2% in cirrhosis patients, 92.5% in hepatocellular carcinoma (HCC) patients without cirrhosis and 91.9% in HCC patients with cirrhosis. There was no significant difference in the distribution of the HBV/C subgenotypes among patients with different stages of liver disease. CONCLUSIONS: Subgenotypes of HBV/C may not have a clinical impact on the disease progression of chronic hepatitis B in Taiwan.     

HCV HBV感染与肝细胞性肝癌

调查了肝癌高发地区不同肝病患者中丙型肝炎病毒(HCV)感染率。慢性肝病患者绝大多数已被乙型肝炎病毒(HBV)感染。HCV第二代抗体阳性率,肝癌7.3％,肝硬化6.6％,慢性肝炎6.6％和急性肝炎3.4％。两种病毒的复合感染率,肝癌5.1％,肝硬化1.7％,慢性肝炎3.9％和急性肝炎1.1％。在38例HCV抗体阳性的慢性肝病患者中,ALT异常84.2％,有输血史者占57.9％,HCV-RNA阳性率为71.1％。本研究的资料分析提示,在肝癌高发地区尽管HCV抗体阳性率较低,但HCV感染也是肝癌发生的重要病因之一。     

Natural history of hepatitis B

The natural course of hepatitis B virus (HBV) chronic infection is variable, ranging from an inactive HBsAg carrier state to a more or less progressive chronic hepatitis, potentially evolving to cirrhosis and hepatocellular carcinoma (HCC). Chronic hepatitis may present as typical HBeAg-positive chronic hepatitis B or HBeAg-negative chronic hepatitis B. HBeAg-positive chronic hepatitis is due to wild type HBV; it represents the early phase of chronic HBV infection. HBeAg-negative chronic hepatitis is due to a naturally occurring HBV variant with mutations in the precore or/and basic core promoter regions of the genome; it represents a late phase of chronic HBV infection. The latter form of the disease has been recognized as increasing in many countries within the last decade and it represents the majority of cases in many countries. HBeAg-negative chronic hepatitis B is generally associated with a more severe liver disease with a very low rate of spontaneous disease remission and a low sustained response rate to antiviral therapy. Longitudinal studies of patients with chronic hepatitis B indicate that, after diagnosis, the 5-year cumulative incidence of developing cirrhosis ranges from 8-20%. Morbidity and mortality in chronic hepatitis B are linked to evolution to cirrhosis or HCC. The 5-year cumulative incidence of hepatic decompensation is approximately 20%. The 5-year probability of survival is approximately 80-86% in patients with compensated cirrhosis. Patients with decompensated cirrhosis have a poor prognosis (14-35% probability of survival at 5 years). HBV-related end-stage liver disease or HCC are responsible for at least 500,000 deaths per year.     

中国北方地区321例乙型肝炎病毒相关肝细胞癌患者的流行病学和临床特征分析

背景:我国是肝细胞癌(HCC)高发区,其中大部分HCC与乙型肝炎病毒(HBV)感染相关,有必要对其自然史和临床进程作大样本调查研究。目的:了解中国北方地区HBV相关HCC患者的流行病学和临床特征。方法:对中国北方地区321例HBV相关HCC患者作流行病学问卷调查,行肝功能、甲胎蛋白(AFP)、HBV血清标志物和HBV DNA水平检测,并进行统计分析。结果:321例HBV相关HCC患者中,仅7.2%接受过抗病毒治疗;46.4%和25.5%分别有肝硬化和肝癌家族史;38.3%有饮酒史。21.0%的患者乙型肝炎e抗原(HBeAg)阳性,62.3%乙型肝炎e抗体(HBeAb)阳性,HBeAg阳性者合并肝硬化的比例和HBV DNA水平较高。84.5%的患者HBV DNA阳性,但其中仅42.6%HBV DNA≥5.0log10,HBV DNA高水平者合并肝硬化的比例显著高于HBV DNA低水平者。无症状HBV感染、慢性乙型肝炎、代偿性和失代偿性肝硬化患者分别占4.1%、24.1%、39.0%和32.9%。71.0%的患者AFP升高,但其中仅33.8?P≥400ng/ml。结论:本组HBV相关HCC患者中,HBeAg阳性和高HBV DNA水平者不多,但病情常较重。肝硬化是HCC的重要危险因素,饮酒和肝癌家族史对HCC的发生有一定影响。血清AFP筛查有助于HCC的诊断。     

HBV-specific peptide associated with heat-shock protein gp96

Glycoprotein 96 (gp96), a member of the heat-shock protein family, can elicit priming of antigen-specfic cytotoxic T lymphocytes, when bound to antigenic viral or tumour peptides. We used direct peptide isolation from purified gp96 and microsequencing to show that a virus-specific peptide is bound to gp96 derived from liver tissues of patients with hepatitis B virus (HBV)-induced hepatocellular carcinoma. This virus-specific peptide has potential for engineering tumour vaccines against hepatocellular carcinoma and chronic HBV infection.     

miRNAs as Potential Biomarkers for Viral Hepatitis B and C

Around 257 million people are living with hepatitis B virus (HBV) chronic infection and 71 million with hepatitis C virus (HCV) chronic infection. Both HBV and HCV infections can lead to liver complications such as cirrhosis and hepatocellular carcinoma (HCC). To take care of these chronically infected patients, one strategy is to diagnose the early stage of fibrosis in order to treat them as soon as possible to decrease the risk of HCC development. microRNAs (or miRNAs) are small non-coding RNAs which regulate many cellular processes in metazoans. Their expressions were frequently modulated by up- or down-regulation during fibrosis progression. In the serum of patients with HBV chronic infection (CHB), miR-122 and miR-185 expressions are increased, while miR-29, -143, -21 and miR-223 expressions are decreased during fibrosis progression. In the serum of patients with HCV chronic infection (CHC), miR-143 and miR-223 expressions are increased, while miR-122 expression is decreased during fibrosis progression. This review aims to summarize current knowledge of principal miRNAs modulation involved in fibrosis progression during chronic hepatitis B/C infections. Furthermore, we also discuss the potential use of miRNAs as non-invasive biomarkers to diagnose fibrosis with the intention of prioritizing patients with advanced fibrosis for treatment and surveillance.     

Remote development of hepatocellular carcinoma in patients with liver cirrhosis type B serologically cured for HBs antigenemia with long-standing normalization of ALT values

In this report, we examine two patients with chronic hepatitis B virus (HBV) infection that had been diagnosed as precirrhosis or liver cirrhosis more than a decade previously. These patients had been cleared of HBsAg and had developed anti-HBs at a later time, yet hepatocellular carcinoma (HCC) eventually occurred. Both patients had been found negative for HBV DNA, using sensitive methods. Interestingly, a nontumor specimen of the liver obtained at surgical resection showed a marked reduction of fibrosis when compared to the histology observed when the patient was diagnosed as precirrhosis. Our findings suggest that the fibrosis from liver cirrhosis had been absorbed to a large extent during the long-term absence of active viremia and the normalization of alanine aminotransferase (ALT) levels. However, the cancer-prone biological characteristics of liver cirrhosis remained. Thus, patients with liver cirrhosis due to past chronic hepatitis B should be monitored carefully for the development of HCC even if HBV infection has been serologically resolved.