High prevalence and mapping of pre-S deletion in hepatitis B virus carriers with progressive liver diseases

Combination of preS deletions and A1762T/G1764A mutations in HBV subgenotype C2 increases the risk of developing HCC

BACKGROUND

The interactions among hepatitis B virus (HBV) mutations in developing hepatocellular carcinoma (HCC) remain unclear and thus we investigated the risk of HCC related with single or multiple HBV mutations in Korean patients infected with HBV subgenotype C2.

METHODS

From January 2003 to December 2008, HBV isolates from 135 patients with HCC were compared with those from 135 patients without HCC, matching for age, gender, and HBeAg status. The prevalence of preS deletions and G1896A and A1762T/G1764A mutations was evaluated.

RESULTS

The frequency of preS deletions significantly differed between the non-HCC and HCC groups, with 6 (4.4%) versus 25 (18.5%) patients, respectively (p < 0.001). Additionally, the frequency of A1762T/G1764A mutations was higher in the HCC than the non-HCC group [82 (60.7%) versus 30 (22.2%), p < 0.001]. For combined mutations, the odds ratio (OR) was highest in patients with both preS deletions and the A1762T/G1764A mutation, with 1 (0.7%) versus 11 (8.1%) patients (p = 0.005; OR 11.887).

CONCLUSIONS

HCC was associated with preS deletions and A1762T/G1764A mutations, and the combination of both mutations had a stronger association with HCC in Korean patients infected with HBV subgenotype C2.

Clinical and virological characteristics of patients with chronic hepatitis B during immune clearance or reactivation

AIM: To investigate the clinical and virological characteristics of patients with chronic hepatitis B (CHB) during the immune clearance or reactivation phases.

METHODS: Five hundred and seventy CHB patients during the immune clearance or reactivation phases who had a disease history of more than 12 mo were selected from Yan'an region in China. These patients were divided into three age groups (< 20, 20-40, > 40). Serum levels of HBV DNA and HBeAg were measured by real-time fluorescence quantitative polymerase chain reaction (FQ-PCR) and time-resolved fluoroimmunoassay (TRFIA), respectively. Serum level of anine aminotransferase (ALT) was also measured.

RESULTS: Patients (166/270) during the reactivation phase were mostly aged above 40 years (166/270) and more likely to be males (P = 0.000, 0.002). Cases with an ALT level two times less than the normal value accounted for considerable proportions in patients during the reactivation phase (12.59%, 45.93%). Patients during the immune clearance were distributed mainly in the 20-40 age group (153/300). Of 300 patients during the immune clearance phase who were followed up for more than 50 mo, 193 achieved spontaneous HBeAg seroconversion. Younger patients achieved HBeAg seroconversion in a shorter time than older ones (P = 0.001, 0.004).

CONCLUSION: There are significantly different clinical and virological characteristics among patients during immune clearance or reactivation in different age groups.

Hepatitis B virus induces G1 phase arrest by regulating cell cycle genes in HepG2.2.15 cells

Background

To investigate the effect of HBV on the proliferative ability of host cells and explore the potential mechanism.

Methods

MTT, colony formation assay and tumourigenicity in nude mice were performed to investigate the effect of HBV on the proliferative capability of host cells. In order to explore the potential mechanism, cell cycle and apoptosis were analysed. The cell cycle genes controlling the G1/S phase transition were detected by immunohistochemistry, westernblot and RT-PCR.

Results

HepG2.2.15 cells showed decreased proliferation ability compared to HepG2 cells. G1 phase arrest was the main cause but was not associated with apoptosis. p53, p21 and total retinoblastoma (Rb) were determined to be up-regulated, whereas cyclinE was down-regulated at both the protein and mRNA levels in HepG2.2.15 cells. The phosphorylated Rb in HepG2.2.15 cells was decreased.

Conclusions

Our results suggested that HBV inhibited the capability of proliferation of HepG2.2.15 cells by regulating cell cycle genes expression and inducing G1 arrest.

The underlying mechanisms for the "simultaneous HBsAg and anti-HBs serological profile"

The course of HBV infection is determined by the interplay between viral replication via HBV protein production and the host's immune response. Therefore, the diagnosis of infection in clinical practice is established by the serological detection of HBV protein products as well as antibodies produced by the host. Although the serological findings for assessing the clinical course of infection are already well established, the expression of viral proteins and the dynamics of antibody production may vary during the natural course of infection. This causes the HBV infection to be occasionally associated with the presence of unusual serologic profiles, which can lead to doubts in the interpretation of results and mistaken serological diagnosis. The simultaneous detection of HBsAg and anti-HBs in the blood stream comprises an atypical serological profile, somewhat incoherent, whose significance can be complicated to establish. Outlined in this article are some immunological and molecular mechanisms which could justify the existence of this profile in which there is a great laboratorial and clinical interest.

A matched case-control study of hepatitis B virus mutations in the preS and core promoter regions associated independently with hepatocellular carcinoma

This study aimed to determine hepatitis B virus (HBV) mutations associated independently with the risk of hepatocellular carcinoma (HCC), as adjusted with other mutations in the preS and core promoter regions of HBV genotypes B and C. One hundred and forty HBV-infected patients with HCC and 280 HBV-infected patients without HCC who had intact data of HBV genotyping and DNA sequencing in both regions were involved in this age-, sex-matched case-control study. Univariate and two-step stepwise multivariate regression analyses were performed to determine factors associated with the risk of HCC. Of 39 mutations evaluated, 23 in genotype C and 6 in genotype B were associated with an increased risk of HCC in the univariate analysis. Multivariate analyses established that genotype C (adjusted odds ratio [AOR] = 3.3; 95% confidence interval [CI] = 1.1-9.8), viral load (≥10(4) copies/ml) (AOR = 2.4; 95% CI = 1.0-5.8), A2962G (AOR = 18.7; 95% CI = 7.5-46.7), preS2 start codon mutation (AOR = 12.5; 95% CI = 3.4-45.5), C105T (AOR = 0.1; 95% CI = 0.0-0.2), T1753V (AOR = 3.1; 95% CI = 1.1-9.2), and A1762T/G1764A (AOR = 2.9; 95% CI = 1.1-7.3) were associated independently with HCC, adjusted for factors including mutations in both regions. By using an estimating haplotype frequencies program, it was found that a haplotypic carriage with 105C and 2962G was significantly more frequent in the patients with HCC than in those without HCC and the frequency of haplotype 2962G-preS2 start codon wildtype-105C-1762T/1764A was 47.9% in the patients with HCC and 4.3% in those without HCC. Conclusively, A2962G and T105C are novel factors associated independently with HCC. Further prospective studies are needed to confirm the role of these mutations in the development of HCC.

Recent advances in the research of hepatitis B virus-related hepatocellular carcinoma: epidemiologic and molecular biological aspects

Hepatocellular carcinoma (HCC) is one of the commonest cancers worldwide, and more than half of HCC patients are attributable to persistent hepatitis B virus (HBV) infections. The best and cheapest way to prevent HBV-related HCC is the implementation of universal hepatitis B vaccination program, by which the incidence rates of childhood HCC have been reduced in several countries, including Taiwan. However, there are still hundreds of millions of HBV carriers in the world that remain a global health challenge. In the past decade, several hepatitis B viral factors such as serum HBV DNA level, genotype, and naturally occurring mutants have already been identified to influence liver disease progression and HCC development in HBV carriers. Several easy-to-use scoring systems based on clinical and viral characteristics are developed to predict HCC risk in HBV carriers and may facilitate the communication between practicing physicians and patients in clinical practice. In addition, the role of nonviral factors in HBV-related HCC has also been increasingly recognized. On the basis of these emerging data, it is recommended that HBV carriers should be screened and monitored to identify those who have a higher risk of liver disease progression and require antiviral treatments. Regarding the molecular carcinogenesis of HCC development, despite some progress in the research of cell biology of HCC in the past decade, aberrant pathways involved in maintaining HCC phenotypes have not been completely elucidated yet. In the future, through comprehensive and integrated approaches to analyze the genomes of human HCC, novel target genes or pathways critically involved in hepatocarcinogenesis may hopefully be identified.

Molecular methods in the diagnosis and management of chronic hepatitis B

Chronic hepatitis B (CHB) infection remains a major global problem but the recent advances in molecular methods have revolutionized the diagnosis and management of CHB. Hepatitis B virus (HBV) DNA quantitation is the most useful molecular marker for the diagnosis and management of CHB. There is increasing evidence that the clinical outcome and efficacy of antiviral therapy for CHB could vary with the infecting HBV genotype, core promoter and precore mutations. Early identification of drug resistance is imperative in the management of CHB. The molecular methods for HBV DNA quantitation, HBV genotyping, the identification of mutants, genotypic and phenotypic methods for monitoring drug resistance and their utility and limitations for use in the diagnosis and monitoring of CHB are discussed in this article.

Association of hepatitis B virus pre-S deletions with the development of hepatocellular carcinoma in chronic hepatitis B

BACKGROUND

We aimed to determine whether hepatitis B virus (HBV) pre-S deletion was an independent factor for the development of hepatocellular carcinoma (HCC).

METHODS

Pre-S deletions were determined in HBV isolates from 115 chronic hepatitis B (CHB) patients with HCC. Sixty-nine patients were further matched with 69 CHB patients without HCC for age, sex, hepatitis B e antigen (HBeAg) status, and HBV genotype.

RESULTS

HBV pre-S deletions were clustered mainly in the 3' end of pre-S1 and 5' end of pre-S2 regions. Adjusted for confounding risk factors, patients with HCC had a higher prevalence of HBV with pre-S deletions than did patients without HCC (23 [33.3%] of 69 vs 11 [15.9%] of 69; P = .018; odds ratio [OR], 2.64). In particular, only pre-S2 deletions but not pre-S1 deletions were significantly associated with the development of HCC (P = .020). A higher prevalence of pre-S deletions was observed in HBV isolates from HCC patients under the age of 50 years than from those older than 50 years (10 [62.5%] of 16 vs 13 [24.5%] of 53; P = .012; OR, 5.13). Emergence of de novo pre-S deletions was documented before the development of HCC.

CONCLUSIONS

HBV pre-S2 deletions were an independent factor associated with the development of HCC. Its oncogenic role may be more important in young patients with HCC.

Combined pre-S deletion and core promoter mutations related to hepatocellular carcinoma: A nested case-control study in China

AIM

  To investigate the roles of biomedical factors, hepatitis B virus (HBV) DNA levels, genotypes, and specific viral mutation patterns on the progression of hepatocellular carcinoma (HCC) in Qidong, China.

METHODS

  A total of 2387 males (aged 20-65 years) who were seropositive for the hepatitis B surface antigen (HBsAg), but had not been diagnosed with HCC, were recruited to a community-based HCC screening study from August, 1996. Evaluation of virological parameters at recruitment was determined for 196 HCC patients during 10 years of follow-up and 323 controls.

RESULTS

  After adjustment for age at recruitment, history of cigarette smoking and alcohol consumption, alanine aminotransferase (ALT) elevation, alpha-fetoprotein (AFP) levels >20 ng/mL, hepatitis B e antigen positive, HBV DNA levels ≥4.00 log(10) copies/mL, pre-S deletion, T1653 mutation, T1762/A1764 double mutations, and T1766 and/or A1768 mutations were associated with subsequent risk of HCC. A significant biological gradient of HCC risk by HBV DNA levels from less than 2.69 log(10) copies/mL to 6.00 log(10) copies/mL or greater was observed. HBV with a complex mutation combination pattern (pre-S deletion, T1762/A1764 double mutations, and T1766 and/or A1768 mutations) rather than a single mutation was associated with the development of HCC. The longitudinal observation demonstrated a gradual combination of pre-S deletion, T1762/A1764 double mutations, and T1766 and/or A1768 mutations during the development of HCC.

CONCLUSIONS

  AFP levels >20 ng/mL, high HBV DNA levels, pre-S deletion, and T1762/A1764 double mutations at recruitment were independent risk factors of HCC. Combination of pre-S deletion and core promoter mutations increased the risk of HCC.

Management of hepatitis B: Consensus of the Japan Society of Hepatology 2009

Recently, much progress has been made in the field of hepatitis B, such as natural history of the disease in relation to the amount of hepatitis B virus (HBV) DNA, genotypes of HBV influencing the natural course and treatment effects, mutations of HBV influencing the severity of the disease and development of hepatocellular carcinoma, and antiviral treatment such as nucleos(t)ide analogues and pegylated interferon. To make the consensus for the diagnosis, management and treatment of hepatitis B, a meeting was held during 45th annual meeting of Japan Society of Hepatology (JSH) in June 2009. In the meeting, recommendations and informative statements were discussed on the following subjects: (i) natural history of HBV infection; (ii) clinical implication of HBV genotypes; (iii) HBV mutations and their potential impact on pathogenesis of HBV infection; (iv) indications for antiviral treatment of chronic hepatitis B; (v) nucleos(t)ide analogues for chronic hepatitis B; and (vi) interferon therapy for chronic hepatitis B. The presenters reviewed the data on these subjects and proposed the consensus statements and recommendations. These statements were discussed among the organizers and presenters, and were approved by the participants of the meeting. In the current report, the relevant data were reviewed and the 12 consensus statements and nine recommendations on chronic hepatitis B were described.

The clinical implications of hepatitis B virus genotype: Recent advances

Outcomes of chronic hepatitis B virus (HBV) infection are heterogeneous. Estimates of annual incidence of cirrhosis and hepatocellular carcinoma (HCC) are 2-10% and 1-3%, respectively. Several viral factors, including HBV genotype, viral load and specific viral mutations, have been associated with disease progression. Among these, HBV genotype is not only predictive of clinical outcomes but has also been associated with response to interferon treatment. Currently, at least 10 HBV genotypes and several subtypes have been identified; they have distinct geographic distribution. Acute infection with genotypes A and D results in higher rates of chronicity than genotypes B and C. Compared to genotype A and B cases, patients with genotypes C and D have lower rates of spontaneous hepatitis B e antigen (HBeAg) seroconversion; when this occurs, it tends to be delayed. HBV genotype C has a higher frequency of basal core promoter (BCP) A1762T/G1764A mutation, pre-S deletion and is associated with higher viral load than genotype B. Similarly, genotype D has a higher prevalence of BCP A1762T/G1764A mutation than genotype A. These observations suggest important pathogenic differences between HBV genotypes. These may contribute to more severe liver disease, including cirrhosis and HCC with genotypes C and D HBV infection. In addition, genotype A and B patients have better responses to interferon-based therapy than genotypes C and D, but there are few consistent differences for direct HBV antivirals. In conclusion, genotyping of chronic HBV infections can help practicing physicians identify those at risk of disease progression and determine optimal anti-viral therapy.

Hepatitis B virus-DNA level and basal core promoter A1762T/G1764A mutation in liver tissue independently predict postoperative survival in hepatocellular carcinoma

Hepatitis B virus (HBV) is a major etiological factor of hepatocellular carcinoma (HCC). However, the postoperative prognostic value of the virological factors assayed directly from liver tissue has never been investigated. To address this issue, 185 liver samples obtained from the noncancerous part of surgically removed HBV-associated HCC tissues were subjected to virological analysis. Assayed factors included the amount of HBV-DNA in the liver tissues; genotype; and the presence of the HBV precore stop codon G1896A mutation, basal core promoter A1762T/G1764A mutation, and pre-S deletions/stop codon mutation. All virological factors and clinicopathological factors were subjected to Cox proportional hazard model analysis to estimate postoperative survival. It was found that an HBV-DNA level >3.0 × 10(7) copies/g of liver tissue and the presence of the basal core promoter mutation independently predicted disease-free (adjusted hazard ratio 1.641 [95% confidence interval (CI) 1.010-2.667] and 2.075 [95% CI 1.203-3.579], respectively) and overall (adjusted hazard ratio 2.807 [95% CI 1.000-7.880] and 5.697 [95% CI 1.678-19.342], respectively) survival. Kaplan-Meier survival analysis indicated that in-frame, short stretch (<100 bp) pre-S deletions, but not large fragment (>100 bp) pre-S deletions, were significantly associated with poorer disease-free (P = 0.005) and overall (P = 0.020) survival. A hot deletion region located between codons 107 and 141 of the pre-S sequence was identified for the short stretch pre-S deletion mutants.

CONCLUSION

The amount of HBV-DNA in liver tissue and the presence of the basal core promoter mutation were two independent predictors for postoperative survival in HCC. A short stretch pre-S deletion located between codons 107 and 141 was strongly associated with a poorer postoperative prognosis.

Significant association of different preS mutations with hepatitis B-related cirrhosis or hepatocellular carcinoma

BACKGROUND

The associations of nucleotide substitution mutations in the preS region of hepatitis B virus (HBV) with hepatocellular carcinoma (HCC) and cirrhosis remain unknown. We aimed to determine the associations of preS mutations with HCC or cirrhosis.

METHODS

HBV from 603 asymptomatic hepatitis B surface antigen carriers (ASCs), 219 chronic hepatitis B (CHB) patients, 119 cirrhosis patients, and 231 HCC patients were genotyped and sequenced in the preS region. Nucleotides with the highest frequencies in HBV from the hepatitis B e antigen (HBeAg)-positive ASCs were treated as "wild-type" nucleotides. Twenty-one preS1 mutations and 14 preS2 mutations were evaluated. Multivariate regression analyses were applied to determine factors independently associated with cirrhosis or HCC.

RESULTS

Most (85.7%) preS2 mutations were associated with CHB compared with ASCs, whereas most preS1 mutations were associated with HCC compared with the cirrhosis patients or CHB patients. Compared with the CHB patients, 81.0% preS1 mutations in genotype C were inversely associated with cirrhosis. Multivariate regression analyses showed that C2964A, C3116T, and C7A were novel factors associated with HCC compared with those without HCC, whereas A2964C and T3116C were independently associated with cirrhosis compared with ASCs and the CHB patients. Combined preS1 mutations had specificities greater than 95%, while C3116T and C7A had moderate sensitivities and specificities, for HCC.

CONCLUSIONS

C2964A, C3116T, and C7A are novel markers independently associated with an increased risk of HCC, while A2964C and T3116C are novel markers independently associated with an increased risk of cirrhosis. Combined preS1 mutations are specific for HCC.

Molecular epidemiological study of hepatitis B virus among migrant workers from Cambodia, Laos, and Myanmar to Thailand

Although hepatitis B virus (HBV) infection is endemic in Southeast Asia, molecular epidemiological data on HBV circulating in some countries are limited. The aims of this study were to evaluate the seroprevalence of HBV and its genetic variability among migrant workers from Cambodia, Laos, and Myanmar in Thailand. Sera collected from 1,119 Cambodian, 787 Laotian, and 1,103 Myanmarese workers were tested for HBsAg. HBV DNA was amplified and the pre-S/S region was sequenced for genotyping and genetic mutation analysis. HBsAg was detected in 282 (9.4%). The prevalence of HBsAg among migrant workers from Cambodia, Laos, and Myanmar was 10.8%, 6.9%, and 9.7%, respectively. Of 224 subjects positive for HBV DNA, 86% were classified as genotype C (99% were sub-genotype C1) and 11.6% were genotype B (30.8%, 34.6%, and 30.8% were sub-genotypes B2, B3, and B4, respectively). Various point mutations in the "a" determinant region were detected in approximately 18% of these samples, of which Ile126Ser/Asn was the most frequent variant. Sequencing analysis showed that 19.1% of samples had pre-S mutations, with pre-S2 deletion as the most common mutant (7.7%) followed by pre-S2 start codon mutation (3.8%) and both pre-S2 deletion and start codon mutation (3.3%). High prevalence of HBV infection (approximately 7-11%) was found among migrant workers from Cambodia, Laos, and Myanmar, which may reflect the current seroprevalence in their respective countries. The data also demonstrated that HBV sub-genotype C1 was the predominant strain and various mutations of HBV occurring naturally were not uncommon among these populations.

A case-control study on sequence variations in the enhancer II/core promoter/precore and X genes of hepatitis B virus in patients with hepatocellular carcinoma

PURPOSE

To evaluate the sequence variations in the enhancer II (EnhII)/basal core promotor (BCP)/precore (PC) and X genes of hepatitis B virus (HBV) in Thai patients with hepatocellular carcinoma (HCC) by conducting a cross-sectional case-control study.

METHODS

As much as 60 patients with HCC and 60 patients without HCC, who were matched for sex, age, hepatitis B e antigen (HBeAg) status, and HBV genotype, were included. Viral mutations in the EnhII/BCP/PC and X regions were characterized by direct sequencing in serum samples.

RESULTS

The prevalence of T1753C/A, A1762T/G1764A and G1899A mutations were significantly higher in the HCC group compared to the non-HCC group (43.3 vs. 23.3%, P = 0.02; 88.3 vs. 53.0%, P < 0.001; and 35.0 vs. 8.3%, P = 0.001, respectively). No significant difference between groups was found with respect to G1613A, C1653T, C1766T/T1768A, A1846T/C, T1858C, and G1896A mutations. By multiple logistic regression analysis, the presence of cirrhosis, A1762T/G1764A and G1899A mutations were independently associated with the risk of HCC.

CONCLUSION

These data suggested that A1762T/G1764A and G1899A mutations were associated with the development of HCC in Thai patients.

HBV mutations in untreated HIV-HBV co-infection using genomic length sequencing

HIV infection has a significant impact on the natural progression of hepatitis B virus (HBV) related liver disease. In HIV-HBV co-infected patients, little is known about mutations in the HBV genome, which can influence severity of liver disease. The aim of this study was to characterize and to determine the frequency of known clinically significant mutations in the HBV genomes from HIV-HBV co-infected patients and from HBV mono-infected patients. To accomplish this, genomic length HBV sequencing was performed in highly-active anti-retroviral therapy (HAART)-naïve HIV-HBV co-infected patients (n=74) and in anti-HBV therapy-naïve HBV mono-infected patients (n=55). The frequency of HBV mutations differed between the co-infected and mono-infected patients when comparing patients with the same genotype. BCP mutations A1762T and G1764A were significantly more frequent in HBV genotype C mono-infection and the -1G frameshift was significantly more frequent in co-infection and was only observed in HBV genotype A co-infection. PreS2 deletions were observed more frequently in the setting of co-infection. Further work is needed to determine if these mutational patterns influence the differences in liver disease progression in HIV-HBV co-infected and HBV mono-infected patients.

Molecular and clinical characteristics of hepatitis B virus in Korea

Korea is an endemic area of hepatitis B virus (HBV) infection but very little is known about the molecular characteristics of HBV isolates from Korean patients or the association with disease progression. The complete HBV genome sequences from 53 Korean patients with chronic hepatitis B, advanced cirrhosis, or hepatocellular carcinoma (HCC) were analyzed to identify (i) subgenotype distribution and genetic diversity and (ii) signature mutations associated with liver disease progression. With the exception of 1 patient infected with HBV/B, all 52 patients (98.1%) were infected with HBV/C, subgenotype C2. These strains were 98.4% identical and the frequency of amino acid substitutions occurring within key immunological epitopes increased with disease severity. A number of amino acid/nucleotide substitutions were associated with HCC, namely sR24K (HBsAg), SI126T (HBsAg), and pcA1846T (precore gene) mutations (P = 0.029, 0.001, and 0.008, respectively). HBV harboring deletions in the pre-S region were also associated with increased liver disease severity (chronic hepatitis B vs. cirrhosis, P = 0.040; chronic hepatitis B vs. HCC, P = 0.040). Despite the high degree of sequence conservation, several key HBV mutations were associated with disease progression. Prospective studies with larger cohorts of patients are required to evaluate further the clinical manifestation of HBV/C2 in Korea.

A comparison of hepatitis B viral markers of patients in different clinical stages of chronic infection

Purpose

Hepatitis B viral markers may be useful for predicting outcomes such as liver-related deaths or development of hepatocellular carcinoma. We determined the frequency of these markers in different clinical stages of chronic hepatitis B infection.

Methods

We compared baseline hepatitis B viral markers in 317 patients who were enrolled in a prospective study and identified the frequency of these tests in immune-tolerant (IT) patients, in inactive carriers, and in patients with either hepatitis B e antigen (HBeAg)-positive or HBeAg-negative chronic hepatitis or cirrhosis.

Results

IT patients were youngest (median age 27 years) and HBeAg-negative patients with cirrhosis were oldest (median age 58 years) (p = 0.03 to <0.0001). The male to female ratio was similar both in IT patients and in inactive carriers, but there was a male preponderance both in patients with chronic hepatitis and in patients with cirrhosis (p < 0.0001). The A1896 precore mutants were most prevalent in inactive carriers (36.4%) and HBeAg-negative patients with chronic hepatitis (38.8%; p < 0.0001), and the T1762/A1764 basal core promoter mutants were most often detected in HBeAg-negative patients with cirrhosis (65.1%; p = 0.02). Genotype A was detected only in 5.3% of IT patients, and genotype B was least often detected in both HBeAg-Positive patients with chronic hepatitis and cirrhosis (p = 0.03). The hepatitis B viral DNA levels were lowest in inactive carriers (2.69 log₁₀ IU/mL) and highest in IT patients (6.80 log₁₀ IU/mL; p = 0.02 to <0.0001). At follow-up, HBeAg-positive and HBeAg-negative patients with cirrhosis accounted for 57 of 64 (89.1%) liver-related deaths (p < 0.0001).

Conclusion

Differences in baseline hepatitis B viral markers were detected in patients in various clinical stages of hepatitis B virus infection. HBeAg-positive and HBeAg-negative patients with cirrhosis accounted for the majority of the liver-related fatalities.

Evolution of full-length HBV sequences in chronic hepatitis B patients with sequential lamivudine and adefovir dipivoxil resistance

BACKGROUND & AIMS

The aim of this study was to determine the evolution of full-length hepatitis B virus (HBV) sequences in chronic hepatitis B (CHB) patients with sequential lamivudine (LAM) and adefovir (ADV) resistance.

METHODS

The full-length genomes of HBV were sequenced from 11 CHB patients before LAM treatment and at the emergence of LAM- and ADV-resistant HBV.

RESULTS

Besides the known LAM-resistant polymerase gene mutations, 10 of 11 patients who had LAM-resistant HBV variants had additional amino acid changes in the reverse transcriptase (RT) domain, and ADV therapy reversed these additional changes to pre-LAM therapy status. Furthermore, new amino acid changes in the RT domain, distinct from the known ADV-resistant HBV variants, were selected at the emergence of ADV resistance in six of 11 patients. Seven patients had amino acid changes within the known T-cell or B-cell epitopes of HBV surface and core antigens at the emergence of LAM and/or ADV resistance. The frequency of pre-S deletions between nucleotide 3037-56 was higher at the emergence of ADV resistance compared with that at the emergence of LAM resistance (7/11 vs. 1/11; p=0.024). Combined LAM-ADV resistance was detected in one of 11 patients. This patient had resistant mutations to both drugs on the same viral genome by molecular cloning (5/24 polymerase gene clones).

CONCLUSIONS

In addition to the known LAM- and ADV-resistant mutations accompanying the emergence of LAM and ADV resistance, the changes of nucleotide or amino acid sequences occurred commonly in the HBV surface antigen or RT domain and were scattered along the full-length HBV genomes.

Asian Pacific Association for the Study of the Liver consensus recommendations on hepatocellular carcinoma

INTRODUCTION

The Asian Pacific Association for the Study of the Liver (APASL) convened an international working party on the management of hepatocellular carcinoma (HCC) in December 2008 to develop consensus recommendations.

METHODS

The working party consisted of expert hepatologist, hepatobiliary surgeon, radiologist, and oncologist from Asian-Pacific region, who were requested to make drafts prior to the consensus meeting held at Bali, Indonesia on 4 December 2008. The quality of existing evidence and strength of recommendations were ranked from 1 (highest) to 5 (lowest) and from A (strongest) to D (weakest), respectively, according to the Oxford system of evidence-based approach for developing the consensus statements.

RESULTS

Participants of the consensus meeting assessed the quality of cited studies and assigned grades to the recommendation statements. Finalized recommendations were presented at the fourth APASL single topic conference on viral-related HCC at Bali, Indonesia and approved by the participants of the conference.

Asian Pacific Association for the Study of the Liver consensus recommendations on hepatocellular carcinoma

INTRODUCTION

The Asian Pacific Association for the Study of the Liver (APASL) convened an international working party on the management of hepatocellular carcinoma (HCC) in December 2008 to develop consensus recommendations.

METHODS

The working party consisted of expert hepatologist, hepatobiliary surgeon, radiologist, and oncologist from Asian-Pacific region, who were requested to make drafts prior to the consensus meeting held at Bali, Indonesia on 4 December 2008. The quality of existing evidence and strength of recommendations were ranked from 1 (highest) to 5 (lowest) and from A (strongest) to D (weakest), respectively, according to the Oxford system of evidence-based approach for developing the consensus statements.

RESULTS

Participants of the consensus meeting assessed the quality of cited studies and assigned grades to the recommendation statements. Finalized recommendations were presented at the fourth APASL single topic conference on viral-related HCC at Bali, Indonesia and approved by the participants of the conference.

Molecular evolutionary analysis and mutational pattern of full-length genomes of hepatitis B virus isolated from Belgian patients with different clinical manifestations

Molecular evolutionary patterns of 62 HBV full-length genomes obtained from Belgian patients were characterized. Phylogenetic analysis revealed diverse HBV subgenotypes including A2 and A6 (46.8%), D1-D4 (38.8%), E (9.7%), C1 (1.6%), and B2 (1.6%). The study population consisted of patients with different ethnic origin (Caucasian, Turkish, Asian, Arab, and African). One HBV D/C recombinant isolate was identified, which encoded subtype adw2. An HBV subgenotype D4 with an aberrant subtype ayw4 was detected. Although none of the genotypes was associated with a specific disease outcome, several nucleotide substitutions, deletions and insertions were observed within the HBV preS1/S and X genes, particularly among patients with active chronic hepatitis B infection and patients with cirrhosis. Within the immunological domain of the HBsAg gene, the most frequent substitutions were sT125M and sT118A. High rates of precore and basal core promoter mutations were detected in patients infected with genotype D of HBV. Almost half of the patients who received lamivudine therapy for at least 1 year had HBV variants associated with lamivudine drug resistance. In conclusion, the most common HBV genotypes in West Europe (A and D) also prevail in Belgium. The highest degree of genetic diversity was detected in HBV genotype D. In addition, this study reveals the circulation of exotic HBV genotypes B, C, and E in Belgium. J. Med. Virol. 82:379-389, 2010. (c) 2010 Wiley-Liss, Inc.

PreS deletion mutations of hepatitis B virus in chronically infected patients with simultaneous seropositivity for hepatitis-B surface antigen and anti-HBS antibodies

Hepatitis B surface antigen (HBsAg) and anti-HBs antibodies (anti-HBs) may coexist in certain chronic hepatitis B (CHB) patients. This study was designed to further explore the relationship between this coexistence and hepatitis B Virus (HBV) preS deletions. Sera of 28 patients carrying both HBsAg and anti-HBs (Group I) and those of another 28 HBsAg positive but anti-HBs negative patients (Group II) were collected from CHB patients. Direct sequencing of polymerase chain reaction products or sequencing of clones was applied to both groups to determine sequences of HBV preS and S genes. Genotyping of the S gene indicated that all sampled HBVs were either Genosubtype Ba or Genosubtype Ce. Seven samples in Group I harbored HBV preS deletion mutations. Three of the seven samples showed large deletion mutations in 3' terminus of preS1 and co-existence of the mutant type and the full-length wild type, and the remaining four samples showed deletion mutations in 5' terminus of preS2. All mutant strains were found to be genosubtype Ce. Only two samples in Group I showed G145R/A mutation. Only one sample in Group II contained preS deletion mutation. It is therefore concluded that HBV preS deletion mutations are likely to be related to the coexistence of HBsAg and anti-HBs in CHB patients (P-value = 0.024). Some immune reactions may select for the preS deletion in CHB patients with anti-HBs, the possible marker for immune selection.

Clinical relevance and public health significance of hepatitis B virus genomic variations

Ten hepatitis B virus (HBV) genotypes (A-J) and 34 HBV subgenotypes have been identified so far. HBV genotypes and subgenotypes have distinct geographical distributions, and have been shown to differ with regard to clinical outcome, prognosis, and response to interferon treatment. Infection with subgenotype A2 is frequently associated with high viral load, resulting in acute infection via horizontal transmission. Genotypes A and B are more sensitive to interferon treatment than genotypes D and C, respectively. Genotype B is more frequent in acute hepatitis than genotype C, whereas genotype C (C2) is more frequently associated with an increased risk of hepatocellular carcinoma (HCC), mostly cirrhotic, as compared with genotype B (B2). Genotype mixture is associated with high viral load and worse outcome of HBV infection. HBV mutations in the S genes, especially amino acids substitution at position 145 (G145R), are associated with immune escape, whereas mutations in the PreS or S genes which impair HBsAg secretion could present a risk to blood safety. HBV variants harboring mutations in the viral polymerase gene that confer resistance to nucleoside analogs may be selected during antiviral therapy. Different genotypes have distinct mutation patterns in the PreS and EnhII/BCP/Precore regions. PreS deletions, C1653T, T1753V, and A1762T/G1764A are associated with an increased risk of HCC. HCC-associated HBV mutants may not transmit via mother-to-child transmission, and are likely generated during HBV-induced pathogenesis. Examination of HBV mutations alone or in combination and host genetic susceptibility will be helpful in classifying the HBV-infected subjects who will develop HCC and need active anti-viral treatments.

Hepatitis B viral surface mutations in patients with adefovir resistant chronic hepatitis B with A181T/V polymerase mutations

The hepatitis B virus (HBV) polymerase gene has overlapping reading frames with surface genes, which allows to alter the amino acid codon of the surface genes. In adefovir (ADV) treated chronic hepatitis B patients carrying rtA181T/rtA181V mutations, overlap with surface gene mutations such as sW172stop/sL173F has been reported. However, the clinical consequences of such surface mutations have not been determined. The aim of this study was to determine the surface gene sequence in ADV-resistant patients carrying the A181T/V mutation and to describe the clinical significance. Of the 22 patients included in this study, 13 were ADV-resistant with rtA181T/V mutations (polymerase mutation group, Group P) and nine were antiviral treatment-naïve (control group, Group C). The Pre-S1 gene mutation, V60A, was detected in 11 patients (Group P=8, Group C=3). A start codon mutation in the Pre-S2 gene was found in five patients (Group P=3, Group C=2). An S gene mutation, sA184V, was found in nine patients, all of whom were in group P. Although sW172stop and sL173F mutations were detected, reduced HBsAg titer was not observed. Further study of these mutations and their clinical implications are needed.

Distinct hepatitis B virus dynamics in the immunotolerant and early immunoclearance phases

Little is known about hepatitis B virus (HBV) diversity changes within a host during the immunotolerant phase of chronic HBV infection. Such knowledge, nevertheless, may help in understanding how host immunity and HBV interact at the early stage of infection. In this study, serial serum samples were collected from a long-term (>17 years) follow-up cohort of seven patients, and multiple copies of the full-length viral genome from serially sampled sera were recovered and analyzed. Viral genetic diversity was positively correlated with host immunity, represented by levels of alanine aminotransferase (ALT), but was negatively correlated with the viral copy number. During the immunotolerant phase, when the host immunity was feeble (ALT < 20 U/liter), viral nucleotide diversity decreased while copy numbers increased. Rates of evolutionary change derived for different patients were in a very narrow range (1.6 x 10(-5) to 5.4 x 10(-5)/site/year). As the disease progressed toward the immunoclearance phase (ALT > 20 U/liter), viral diversity increased but copy numbers decreased. Evolutionary rates varied among patients in accordance with their levels of ALT, ranging from 9.6 x 10(-6) to 3.2 x 10(-4)/site/year. More than half (19/32 sites) of positively selected sites resided in immune epitopes, suggesting their possible role in host immunity. Our results demonstrate that host immunity is a dominant factor in HBV evolution. Different selective forces, including immune-mediated positive selection and virus-mediated negative selection, operate in tandem in shaping viral population dynamics within a host.

Distinct hepatitis B virus dynamics in the immunotolerant and early immunoclearance phases

Little is known about hepatitis B virus (HBV) diversity changes within a host during the immunotolerant phase of chronic HBV infection. Such knowledge, nevertheless, may help in understanding how host immunity and HBV interact at the early stage of infection. In this study, serial serum samples were collected from a long-term (>17 years) follow-up cohort of seven patients, and multiple copies of the full-length viral genome from serially sampled sera were recovered and analyzed. Viral genetic diversity was positively correlated with host immunity, represented by levels of alanine aminotransferase (ALT), but was negatively correlated with the viral copy number. During the immunotolerant phase, when the host immunity was feeble (ALT < 20 U/liter), viral nucleotide diversity decreased while copy numbers increased. Rates of evolutionary change derived for different patients were in a very narrow range (1.6 x 10(-5) to 5.4 x 10(-5)/site/year). As the disease progressed toward the immunoclearance phase (ALT > 20 U/liter), viral diversity increased but copy numbers decreased. Evolutionary rates varied among patients in accordance with their levels of ALT, ranging from 9.6 x 10(-6) to 3.2 x 10(-4)/site/year. More than half (19/32 sites) of positively selected sites resided in immune epitopes, suggesting their possible role in host immunity. Our results demonstrate that host immunity is a dominant factor in HBV evolution. Different selective forces, including immune-mediated positive selection and virus-mediated negative selection, operate in tandem in shaping viral population dynamics within a host.

Pre-S2 deletions of hepatitis B virus and hepatocellular carcinoma in children

The cause of early oncogenesis in hepatitis B virus (HBV)-related childhood hepatocellular carcinoma (HCC) remains unclear. This study investigated whether pre-S deletion of HBV is related to childhood HCC. By using nested polymerase chain reaction, we compared the pre-S sequence of HBV from sera of children with HCC against control children with similar chronic HBV infection. The HBV in sera of children with HCC had a significantly higher rate of pre-S deletion than that of children with chronic HBV infection (p = 0.008). All except one of the pre-S deletions from the HCC group involved the pre-S2 region, whereas no pre-S2 deletion was found in the chronic HBV group (p = 0.003). There was a trend whereby genotype-C sera had a higher rate of pre-S2 deletion than genotype-B sera (p = 0.11). A multivariate logistic regression model revealed that pre-S deletion was an independent risk factor for HCC in children (odds ratio: 36.69, p = 0.015). In conclusion, pre-S2 deletion does not need to take decades to occur; its presence in nearly half of children with HCC, in contrast to its absence in children with chronic HBV infection, suggests a link between pre-S2 deletion and HCC development in children.

Clinical relevance and public health significance of hepatitis B virus genomic variations

Ten hepatitis B virus (HBV) genotypes (A-J) and 34 HBV subgenotypes have been identified so far. HBV genotypes and subgenotypes have distinct geographical distributions, and have been shown to differ with regard to clinical outcome, prognosis, and response to interferon treatment. Infection with subgenotype A2 is frequently associated with high viral load, resulting in acute infection via horizontal transmission. Genotypes A and B are more sensitive to interferon treatment than genotypes D and C, respectively. Genotype B is more frequent in acute hepatitis than genotype C, whereas genotype C (C2) is more frequently associated with an increased risk of hepatocellular carcinoma (HCC), mostly cirrhotic, as compared with genotype B (B2). Genotype mixture is associated with high viral load and worse outcome of HBV infection. HBV mutations in the S genes, especially amino acids substitution at position 145 (G145R), are associated with immune escape, whereas mutations in the PreS or S genes which impair HBsAg secretion could present a risk to blood safety. HBV variants harboring mutations in the viral polymerase gene that confer resistance to nucleoside analogs may be selected during antiviral therapy. Different genotypes have distinct mutation patterns in the PreS and EnhII/BCP/Precore regions. PreS deletions, C1653T, T1753V, and A1762T/G1764A are associated with an increased risk of HCC. HCC-associated HBV mutants may not transmit via mother-to-child transmission, and are likely generated during HBV-induced pathogenesis. Examination of HBV mutations alone or in combination and host genetic susceptibility will be helpful in classifying the HBV-infected subjects who will develop HCC and need active anti-viral treatments.

Pre-S2 deletion mutants of hepatitis B virus could have an important role in hepatocarcinogenesis in Asian children

Although many studies on the risk factors and their carcinogenesis in adult hepatocellular carcinoma (HCC) have been reported, they remain poorly understood in childhood HCC. A retrospective study of 42 HCC cases in Asian children was conducted. Hepatitis B virus (HBV)-DNA in HCC tissues was detected in 36 of 42 (86%) cases tested, while no hepatitis C virus (HCV)-RNA was detectable in any of HCCs. Twenty of 36 (56%) HCC cases were accompanied by cirrhosis. Surprisingly, very high prevalence of the HBV pre-S deletion mutant was recognized in 27 of 30 (90%) HCCs examined. They occurred most frequently in pre-S2 (20/27, 74%) followed by pre-S1 (5/27, 18.5%), and both pre-S1/S2 (2/27, 7.4%). Interestingly, the pre-S2 mutant consistently appeared with deletion at nt 4-57 in all of the 20 cases with the pre-S2 mutant (100%) and within this locus in the two cases with both pre-S-1/S2 mutants. Type II ground-glass hepatocytes in non-tumorous livers were seen in 15 of the 22 HCCs with the pre-S2 deletion mutant (68%). This hotspot mutation in the pre-S2 was further confirmed by complete genomic sequence of HBV in a Japanese boy who eventually developed HCC. Our result strongly suggests that HBV is a major contributor to the development of HCC in Asian children. The HBV pre-S2 deletion mutant at nt 4-57 which has a CD8 T-cell epitope could be responsible for the emergence and aggressive outcome of childhood HCC. Determination of this hotspot mutation in the pre-S2 region could be a useful index for predicting the clinical outcome of HCC development.

T3098C and T53C mutations of HBV genotype C is associated with HBV infection progress

OBJECTIVE

To analyze the association between mutation(s) in preS region of HBV and hepatitis B disease progress in Chinese patients with genotype C chronic HBV infection.

METHODS

Ninety-three patients with chronic genotype C HBV infection, including 24 asymptomatic carriers (ASC), 26 patients with chronic hepatitis B (CHB), 22 patients with liver cirrhosis (LC) and 21 HCC patients were investigated. Levels of HBV DNA, HBeAg, alanine aminotransferase (ALT), asparate transaminase (AST) were measured. HBV preS region was analyzed by PCR direct sequencing.

RESULTS

The prevalence of preS T3098C and T53C mutations of genotype C HBV was significantly higher in LC and HCC patients than ASC and CHB patients. The rate of T3098C mutation in ASC, CHB, LC, and HCC patients were 0.00% (0/24), 3.85% (1/26), 9.09% (2/22), and 30.77% (8/22), respectively (P=0.0015), while the rate of T53C mutation was 12.50% (3/24), 3.85% (1/26), 40.91% (9/22), and 42.31% (11/26), respectively (P=0.0012).

CONCLUSION

The frequency of genotype C HBV preS T3098C and T53C mutations is associated with hepatitis B infection progression

A pre-S gene chip to detect pre-S deletions in hepatitis B virus large surface antigen as a predictive marker for hepatoma risk in chronic hepatitis B virus carriers

BACKGROUND

Chronic hepatitis B virus (HBV) infection is an important cause of hepatocellular carcinoma (HCC) worldwide. The pre-S1 and -S2 mutant large HBV surface antigen (LHBS), in which the pre-S1 and -S2 regions of the LHBS gene are partially deleted, are highly associated with HBV-related HCC.

METHODS

The pre-S region of the LHBS gene in two hundred and one HBV-positive serum samples was PCR-amplified and sequenced. A pre-S oligonucleotide gene chip was developed to efficiently detect pre-S deletions in chronic HBV carriers. Twenty serum samples from chronic HBV carriers were analyzed using the chip.

RESULTS

The pre-S deletion rates were relatively low (7%) in the sera of patients with acute HBV infection. They gradually increased in periods of persistent HBV infection: pre-S mutation rates were 37% in chronic HBV carriers, and as high as 60% in HCC patients. The Pre-S Gene Chip offers a highly sensitive and specific method for pre-S deletion detection and is less expensive and more efficient (turnaround time 3 days) than DNA sequencing analysis.

CONCLUSION

The pre-S1/2 mutants may emerge during the long-term persistence of the HBV genome in carriers and facilitate HCC development. Combined detection of pre-S mutations, other markers of HBV replication, and viral titers, offers a reliable predictive method for HCC risks in chronic HBV carriers.

Treatment of HBV-related cirrhosis

The goal of antiviral therapy in HBV cirrhotic patients is to prevent progression of the disease to decompensated cirrhosis, end-stage liver disease, hepatocellular carcinoma and death. This goal can be achieved if HBV replication can be suppressed, leading to biochemical remission, histological improvement and prevention of complications. If finite treatment with pegylated interferon is not contraindicated in compensated cirrhosis, long-term treatment with nucleoside/nucleotide analogues is recommended in patients with HBV-related cirrhosis, especially in decompensated cirrhosis. Patients with cirrhosis require careful monitoring to detect resistance and prevent flares, and also to screen for hepatocellular carcinoma, portal hypertension and liver failure.

Low pretreatment serum HBsAg level and viral mutations as predictors of response to PEG-interferon alpha-2b therapy in chronic hepatitis B

BACKGROUND

Viral genomic mutations have become increasingly recognized as being associated with the outcome of chronic HBV infection. However, the role of viral mutations as a predictor of response to pegylated-interferon (PEG-IFN) therapy has so far remained unclear.

STUDY DESIGN

Viral mutations in the enhancer II/basal core promoter (BCP)/precore and the pre-S regions were characterized by direct sequencing in pretreatment serum samples of 50 patients with chronic hepatitis B (33 HBeAg-positive and 17 HBeAg-negative), who were treated for 48 weeks with PEG-IFN alpha-2b.

RESULTS

Sustained virological response at 48 weeks post treatment, defined as HBeAg seroconversion and HBV DNA<2000IU/mL for HBeAg-positive patients, and HBV DNA<200IU/mL for HBeAg-negative patients, was achieved in 12 (36.4%) and 6 (35.3%) of HBeAg-positive and HBeAg-negative patients, respectively. Response to PEG-IFN therapy correlated to low pretreatment HBsAg level but did not correlate with HBV genotype, pretreatment alanine transaminase and HBV DNA levels. In HBeAg-positive hepatitis, PEG-IFN response correlated with the appearance of double BCP mutations (A1762T/G1764A) at baseline (P=0.041). In the HBeAg-negative group, response to PEG-IFN therapy was associated with the presence of pre-S mutation/deletions (P=0.028). Multivariate analysis identified low pretreatment HBsAg level as an independent factor associated with SVR in both groups.

CONCLUSIONS

Pretreatment quantitative HBsAg determination is useful for predicting response to PEG-IFN therapy. The presence of double BCP and pre-S mutation/deletions at entry may be associated with a high rate of antiviral response in HBeAg-positive and HBeAg-negative hepatitis, respectively.

Hepatocellular carcinoma: current trends in worldwide epidemiology, risk factors, diagnosis and therapeutics

Hepatocellular carcinoma (HCC) is the third most common cause of cancer-related death worldwide and, owing to changes in the prevalence of the two major risk factors, hepatitis B virus and hepatitis C virus, its overall incidence remains alarmingly high in the developing world and is steadily rising across most of the developed world. Early diagnosis remains the key to effective treatment and there have been recent advances in both the diagnosis and therapy of HCC, which have made important impacts on the disease. This review outlines the epidemiological trends, risk factors, diagnostic developments and novel therapeutics for HCC, both in the developing and developed world.

Associations between hepatitis B virus mutations and the risk of hepatocellular carcinoma: a meta-analysis

Background

The association between hepatitis B virus (HBV) mutations and hepatocarcinogenesis remains controversial because of conflicting data in the literature. We conducted a meta-analysis of case–control and cohort studies to examine HBV PreS, enhancer II (EnhII), basal core promoter (BCP), and precore mutations in relation to the risk of hepatocellular carcinoma (HCC).

Methods

We searched databases for studies of these associations that were published in English or Chinese up to August 31, 2008. HBV mutation–specific odds ratios and relative risks were pooled by use of a random-effects model and stratified by potential confounders. All statistical tests were two-sided.

Results

Of the 43 studies included in this meta-analysis, 40 used a case–control design. The 43 studies evaluated a total of 11 582 HBV-infected participants, of whom 2801 had HCC. Statistically significant summary odds ratios of HCC were obtained for any PreS mutation (3.77, 95% confidence interval [CI] = 2.57 to 5.52), C1653T in EnhII (2.76, 95% CI = 2.09 to 3.64), T1753V (2.35, 95% CI = 1.63 to 3.40), and A1762T/G1764A in BCP (3.79, 95% CI = 2.71 to 5.29). PreS mutations were more strongly associated with an increased risk of HCC in subjects who were infected with HBV genotype C than in those who were infected with HBV genotype B, whereas the opposite was true for A1762T/G1764A. C1653T, T1753V, and A1762T/G1764A were more strongly associated with an increased risk of HCC in hepatitis B e antigen (HBeAg)–positive subjects than in HBeAg-negative subjects. PreS mutations, C1653T, T1753V, and A1762T/G1764A accumulated during the progression of chronic HBV infection from the asymptomatic carrier state to HCC (P_trend < .001 for each mutation). PreS mutations, C1653T, C1653T + T1753V, and A1762T/G1764A-based combinations of mutations had specificities greater than 80% for the prediction of HCC. The precore mutations G1896A and C1858T were not associated with the risk of HCC, regardless of HBeAg status and HBV genotype.

Conclusions

HBV PreS mutations, C1653T, T1753V, and A1762T/G1764A are associated with an increased risk of HCC. These mutations alone and in combination may be predictive for hepatocarcinogenesis.

Associations between hepatitis B virus mutations and the risk of hepatocellular carcinoma: a meta-analysis

BACKGROUND

The association between hepatitis B virus (HBV) mutations and hepatocarcinogenesis remains controversial because of conflicting data in the literature. We conducted a meta-analysis of case-control and cohort studies to examine HBV PreS, enhancer II (EnhII), basal core promoter (BCP), and precore mutations in relation to the risk of hepatocellular carcinoma (HCC).

METHODS

We searched databases for studies of these associations that were published in English or Chinese up to August 31, 2008. HBV mutation-specific odds ratios and relative risks were pooled by use of a random-effects model and stratified by potential confounders. All statistical tests were two-sided.

RESULTS

Of the 43 studies included in this meta-analysis, 40 used a case-control design. The 43 studies evaluated a total of 11 582 HBV-infected participants, of whom 2801 had HCC. Statistically significant summary odds ratios of HCC were obtained for any PreS mutation (3.77, 95% confidence interval [CI] = 2.57 to 5.52), C1653T in EnhII (2.76, 95% CI = 2.09 to 3.64), T1753V (2.35, 95% CI = 1.63 to 3.40), and A1762T/G1764A in BCP (3.79, 95% CI = 2.71 to 5.29). PreS mutations were more strongly associated with an increased risk of HCC in subjects who were infected with HBV genotype C than in those who were infected with HBV genotype B, whereas the opposite was true for A1762T/G1764A. C1653T, T1753V, and A1762T/G1764A were more strongly associated with an increased risk of HCC in hepatitis B e antigen (HBeAg)-positive subjects than in HBeAg-negative subjects. PreS mutations, C1653T, T1753V, and A1762T/G1764A accumulated during the progression of chronic HBV infection from the asymptomatic carrier state to HCC (P(trend) < .001 for each mutation). PreS mutations, C1653T, C1653T + T1753V, and A1762T/G1764A-based combinations of mutations had specificities greater than 80% for the prediction of HCC. The precore mutations G1896A and C1858T were not associated with the risk of HCC, regardless of HBeAg status and HBV genotype.

CONCLUSIONS

HBV PreS mutations, C1653T, T1753V, and A1762T/G1764A are associated with an increased risk of HCC. These mutations alone and in combination may be predictive for hepatocarcinogenesis.

Factors associated with progression to hepatocellular carcinoma and to death from liver complications in patients with HBsAg-positive cirrhosis

BACKGROUND AND AIMS

Hepatitis B viral markers and liver tests were used as predictors for development of hepatocellular carcinoma and progression to end-stage liver disease in 128 cirrhosis patients with hepatitis B.

RESULTS

During a median follow-up of 63.5 months, 28 patients (21.9%) developed HCC and 36 (28.1%) died from non-HCC liver deaths. By multivariate analysis, independent predictors of HCC development and their hazard ratios were high alfa-fetoprotein (HR2.83, 95% CI 1.60-5.00, P = 0.0003), negative HBeAg (HR2.33, 95% CI 1.04-5.29, P = 0.04), and low alanine aminotransferase value (HR1.42, 95% CI 1.08-1.89, P = 0.02). Independent predictors of non-HCC liver deaths were HBeAg positivity (HR3.39, 95% CI 1.16-9.93, P = 0.02), decrease albumin (HR1.61, 95% CI 0.99-2.63, P = 0.05), decrease platelet count (HR2.54, 95% CI 1.03-6.25, P = 0.04), high ALT value (HR1.22, 95% CI 1.03-1.43, P = 0.02), and onset of encephalopathy (HR3.34, 95% CI 1.21-9.27, P = 0.02).

CONCLUSIONS

HBeAg negativity, elevated AFP, and low ALT values predicted HCC development, while HBeAg positivity, abnormal liver tests, and low platelet counts identified patients with non-HCC liver deaths.

Proteome responses to stable hepatitis B virus transfection and following interferon alpha treatment in human liver cell line HepG2

Hepatitis B virus (HBV) infection is a worldwide health problem and may develop to liver fibrosis, cirrhosis, and even hepatocellular carcinoma. To investigate the global proteome responses of liver-derived cells to HBV infection and IFNalpha treatment, 2-DE and MS-based analysis were performed to compare the proteome changes between HBV stably transfected cell line HepG2.2.15 and its parental cell line HepG2, as well as HepG2.2.15 before and after IFNalpha treatment (5000 IU/mL for 72 h). Compared to HepG2, 12 of 18 down-regulated and 27 of 32 up-regulated proteins were identified in HepG2.2.15. After IFNalpha treatment, 6 of 7 down-regulated and 11 of 14 up-regulated proteins were identified. Differentially expressed proteins caused by HBV infection were involved with cytoskeletal matrix, heat shock stress, kinases/signal transduction, protease/proteasome components, etc. Prohibitin showed a dose-dependent up-regulation during IFNalpha treatment and might play a potent role in anti-HBV activities of IFNalpha by enhancing the crossbinding p53 expression to achieve the apoptosis of HBV infected liver cells. Down-regulation of interferon-stimulated gene 15 (ISG15) in HepG2.2.15 and recovery by IFNalpha suggested its relationship with IFNalpha's anti-HBV effect.

Hepatitis B virus basal core promoter mutation and DNA load correlate with expression of hepatitis B core antigen in patients with chronic hepatitis B

BACKGROUND

Expression of intrahepatic hepatitis B core antigen (HBcAg) is related to the immunopathogenesis of hepatitis B virus (HBV) infection. This study investigated the role that HBV genotype and basal core promoter (BCP) mutation play in the expression of HBcAg.

METHODS

A total of 70 hepatitis B e antigen (HBeAg)-positive patients with chronic hepatitis (genotype B in 52 patients and genotype C in 18 patients; BCP mutation T1762/A1764 in 16 patients) were enrolled. Clinical, virologic, and histologic features were compared with regard to localization and expression of intrahepatic HBcAg. The effects that HBV genotype and BCP mutation T1762/A1764 had on expression of HBcAg were further evaluated by in vitro assays.

RESULTS

Cytoplasmic, mixed cytoplasmic/nuclear, and nuclear localization of intrahepatic HBcAg was found in 38 (56.7%), 25 (37.3%), and 4 (6.0%) patients, respectively; HBcAg was not discernible in 3 patients. A total of 58 (82.9%) of these patients expressed a high level of HBcAg. In multivariate analysis, cytoplasmic localization of HBcAg correlated only with a low HBV load in serum (P = .045) and BCP mutation (P = .04). A high expression level of HBcAg also correlated with a high HBV load in serum (P = .015) and with BCP wild-type sequence (P = .037). In vitro assays indicated that the HBV BCP mutant strain had lower subcellular expression of HBcAg than did the BCP wild-type strain.

CONCLUSIONS

HBV BCP mutation and HBV load, but not genotype, contribute to the expression of intrahepatic HBcAg.

[Hepatitis B virus genetic diversity and mutant]

Hepatitis B virus (HBV) is a partially double stranded DNA virus with genetic diversity represented by eight genotypes (A to H). Natural course and response to treatment could be affected by HBV genotypes. HBV shows high rates of turn over in the absence of proof-reading ability. As a result, large amounts of quasispecies are produced naturally or antiviral-associated. HBV consists of four open reading frames, namely preS/S gene, precore/core gene, polymerase gene, and X gene. Mutations on preS gene can result in undetectable HBsAg even in case that HBV is replicating. Surface gene mutation leads to decreased binding affinity to anti-HBs, which is associated with a vaccine escape mutant. Precore mutation abolishes HBeAg whereas mutations on basal core promoter gene down-regulate the HBeAg production. Mutations on basal core promoter are associated with increased HBV replication and high incidence of progressive liver diseases such as liver cirrhosis and hepatocellular carcinoma. Mutations on polymerase genes are often induced by antiviral therapy. Emergence of antiviral-resistant mutation is the major cause of treatment failure. Furthermore, existence of prior antiviral-resistant mutations limits the options of subsequent antiviral agents. Therefore, judicious use of antivirals and selection of the most potent drug with the lowest resistance rate are of the utmost importance for the prevention of antiviral-associated mutants. Detailed knowledge and understanding of HBV genetic diversity and mutant would be critical to establish strategies for the diagnosis and management of HBV infection.

Human leukocyte antigen-DRB1*1101 correlates with less severe hepatitis in Taiwanese male carriers of hepatitis B virus

Human leukocyte antigen (HLA) class II molecules are associated with host immune responses against hepatitis B virus infection. Male gender is the apparent host factor when someone encounters with the severity of hepatitis. The aim of this study was to investigate the association of the most polymorphic HLA class II allele, human leukocyte antigen-DRB1, with the severity of hepatitis in male carriers of hepatitis B virus. In this prospective cohort study, a total of 204 carriers of hepatitis B virus (131 men and 73 women) who have been followed-up for more than 1 year at the outpatient clinic of a university hospital were collected consecutively. Fifty carriers of hepatitis B virus (group I) with alanine aminotransferase <2x upper limit of normal (mean follow-up 83.6 months) were compared with 154 chronic hepatitis B patients (group II) with alanine aminotransferase >/=2x upper limit of normal (mean follow-up 81.3 months). Alleles of HLA-DRB1 were typed by the polymerase chain reaction-sequence specific oligonucleotide probe hybridization and genotypes of hepatitis B virus by melting curve analysis. HLA-DRB1*1101 was found in 18% of group I versus 8% of group II in male carriers (OR 0.23, P = 0.020, after adjustment for age) and 4% versus 9.4% in female carriers (P = 0.094). In male carriers harboring DRB1*1101, the distribution of hepatitis B viral genotype was comparable between the two groups. HLA-DRB1*1101 correlates with less severe hepatitis in Taiwanese male carriers of hepatitis B virus.

Association of baseline viral factors with response to lamivudine therapy in chronic hepatitis B patients with high serum alanine aminotransferase levels

Background

With the exception of alanine aminotransferase (ALT) level, baseline factors predictive of therapeutic response to lamivudine in patients with hepatitis B e antigen (HBeAg)-positive chronic hepatitis B (CHB) remain unknown. We thus studied the influence of pre-therapy viral factors on end-of-treatment responses to lamivudine.

Methods

A total of 116 treatment-naive HBeAg-positive CHB patients who had pre-therapy ALT level >5x the upper limit of normal (ULN) and received lamivudine for 12–18 months were enrolled. HBeAg seroclearance and combined HBeAg seroclearance, ALT normalization and undetectable hepatitis B virus DNA at the end of therapy were defined as primary and secondary endpoints, respectively. Pre-therapy viral factors including viral load, genotype, precore (PC) stop codon status, basal core promoter status and pre-S deletion were determined to correlate with therapeutic endpoints.

Results

The frequency of patients with detectable PC stop codon mutation (G1896A), basal core promoter mutation (A1762T/G1764A) and pre-S deletion at baseline was 22.4%, 21.6% and 12.1%, respectively. After the end of 12–18 months of lamivudine therapy, the overall HBeAg seroclearance rate was 56.0%. Patients with HBeAg seroclearance had a higher prevalence of baseline PC stop codon mutation than those without (30.8% versus 11.8%; P=0.015). By using multivariate analyses, the odds ratio of patients with the PC stop codon mutation to develop HBeAg seroclearance was 3.33 ( P=0.024). The presence of the PC stop codon mutation also correlated with the combined response.

Conclusions

For lamivudine-treated HBeAg-positive CHB patients with pre-therapy ALT levels >5xULN, the PC stop codon mutation could predict a higher HBeAg seroclearance rate at the end of 12–18 months of therapy.

Occult hepatitis B virus infection in hepatitis B vaccinated children in Taiwan

BACKGROUND/AIMS

Presence of occult HBV infection in HBV vaccinated children remains largely unknown. The aim of this study was to investigate the prevalence of occult HBV infection among HBV vaccinated children in Taiwan.

METHODS

Forty-six HBsAg negative sera from vaccinated children were enrolled randomly. HBV serum markers were detected by ELISA, and the titers of HBV DNA were determined by quantitative real-time PCR. Pre-S, S and pre-core/core genes were amplified by nested PCR and analyzed.

RESULTS

Anti-HBs was detected in 23 (50%) children, and the positivity decreased according to age. Five (10.9%) children were classified into occult HBV infection by positivity of nested PCR in at least two regions; they had a low titer (mean titer 1.60x10(4)copies/ml). Sequence analyses of S gene showed occult isolates were variants; no G145R but C139S vaccine escape mutant was found. Variation and deletion were found in pre-S region; pre-S deletion was more frequent in 3' terminus of pre-S1 which leads to loss of immune epitopes and function sites.

CONCLUSIONS

This pilot study indicates that the prevalence of occult HBV infection is 10.9% in HBV vaccinated children. Since this is a small study, a study of a large population is needed to confirm the findings herein.

Hepatitis B virus pre-S deletion mutations are a risk factor for hepatocellular carcinoma: a matched nested case-control study

A matched nested case-control study of 33 paired cases and controls was conducted, based on a study cohort in Long An county, Guangxi, China, to determine whether infection with hepatitis B virus (HBV) with pre-S deletions is independently associated with the development of hepatocellular carcinoma (HCC), without the confounding effects of basal core promoter (BCP) double mutations. The prevalence of pre-S deletions was significantly higher in HCC (45.5 %, 15 of 33) than the controls (18.2 %, 6 of 33) (P<0.01), under the control of the influence of BCP double mutations. Most of the pre-S deletions occurred in, or involved, the 5' half of the pre-S2 region and the difference between HCC (93.3 %, 14 of 15) and controls (66.7 %, four of six) was significant for this region (P=0.015). There was no significant difference in pre-S deletions between the BCP mutant group and BCP wild-type group (P>0.05), nor was the prevalence of pre-S deletions significantly different between genotypes B and C (P>0.1). These results suggest that pre-S deletions constitute an independent risk factor for HCC and their emergence and effect are independent of BCP mutations. The 5' terminus of pre-S2 is the favoured site for the deletion mutations, especially in HCC cases. Further prospective studies are required to confirm the role of these mutations in the development of HCC.