1
|
Bousali M, Papatheodoridis G, Paraskevis D, Karamitros T. Hepatitis B Virus DNA Integration, Chronic Infections and Hepatocellular Carcinoma. Microorganisms 2021; 9:1787. [PMID: 34442866 PMCID: PMC8398950 DOI: 10.3390/microorganisms9081787] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2021] [Revised: 08/13/2021] [Accepted: 08/18/2021] [Indexed: 12/16/2022] Open
Abstract
Hepatitis B Virus (HBV) is an Old World virus with a high mutation rate, which puts its origins in Africa alongside the origins of Homo sapiens, and is a member of the Hepadnaviridae family that is characterized by a unique viral replication cycle. It targets human hepatocytes and can lead to chronic HBV infection either after acute infection via horizontal transmission usually during infancy or childhood or via maternal-fetal transmission. HBV has been found in ~85% of HBV-related Hepatocellular Carcinomas (HCC), and it can integrate the whole or part of its genome into the host genomic DNA. The molecular mechanisms involved in the HBV DNA integration is not yet clear; thus, multiple models have been described with respect to either the relaxed-circular DNA (rcDNA) or the double-stranded linear DNA (dslDNA) of HBV. Various genes have been found to be affected by HBV DNA integration, including cell-proliferation-related genes, oncogenes and long non-coding RNA genes (lincRNAs). The present review summarizes the advances in the research of HBV DNA integration, focusing on the evolutionary and molecular side of the integration events along with the arising clinical aspects in the light of WHO's commitment to eliminate HBV and viral hepatitis by 2030.
Collapse
Affiliation(s)
- Maria Bousali
- Bioinformatics and Applied Genomics Unit, Department of Microbiology, Hellenic Pasteur Institute, 11521 Athens, Greece;
| | - George Papatheodoridis
- Department of Gastroenterology, “Laiko” General Hospital of Athens, Medical School, National and Kapodistrian University of Athens, 11527 Athens, Greece;
| | - Dimitrios Paraskevis
- Department of Hygiene Epidemiology and Medical Statistics, School of Medicine, National and Kapodistrian University of Athens, 15772 Athens, Greece;
| | - Timokratis Karamitros
- Bioinformatics and Applied Genomics Unit, Department of Microbiology, Hellenic Pasteur Institute, 11521 Athens, Greece;
- Laboratory of Medical Microbiology, Department of Microbiology, Hellenic Pasteur Institute, 11521 Athens, Greece
| |
Collapse
|
2
|
Rajput MK. Mutations and methods of analysis of mutations in Hepatitis B virus. AIMS Microbiol 2020; 6:401-421. [PMID: 33364535 PMCID: PMC7755589 DOI: 10.3934/microbiol.2020024] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2020] [Accepted: 10/23/2020] [Indexed: 12/13/2022] Open
Abstract
Immunization programmes against hepatitis-B are being carried out since more than three decades but still HBV is a major public health problem. Hepatitis B virus (HBV) genome consists of circular and partial double stranded DNA. Due to partial double stranded DNA, it uses an RNA intermediate during replication. This replicative strategy of HBV and lack of polymerase proofreading activity give rise to error occurrences comparable to retroviruses. The low fidelity of polymerase, overlapping reading frames and high replication rate produces many non-identical variants at every cycle of replication. Therefore, HBV spreads with mutations and variations. The mutations have been reported both in non-structural as well as structural genes of HBV genome. Recent advances in molecular biology have made easier to analyse these mutations. Hepatitis B antiviral therapy and immunization are all influenced by genetic variability. The analysis and understanding of these mutations are important for therapy against hepatitis B and updating of diagnostic tools. The present review discusses about mutations occurring in whole HBV genome. The mutation occurring both in structural and non-structural genes and non-coding regions have been described in details. It is much more informative because most of literature available, covers only individual gene or DNA regions of HBV.
Collapse
|
3
|
Liu WC, Wu IC, Lee YC, Lin CP, Cheng JH, Lin YJ, Yen CJ, Cheng PN, Li PF, Cheng YT, Cheng PW, Sun KT, Yan SL, Lin JJ, Yang JC, Chang KC, Ho CH, Tseng VS, Chang BCH, Wu JC, Chang TT. Hepatocellular carcinoma-associated single-nucleotide variants and deletions identified by the use of genome-wide high-throughput analysis of hepatitis B virus. J Pathol 2017; 243:176-192. [PMID: 28696069 DOI: 10.1002/path.4938] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2016] [Revised: 05/31/2017] [Accepted: 07/04/2017] [Indexed: 12/26/2022]
Abstract
This study investigated hepatitis B virus (HBV) single-nucleotide variants (SNVs) and deletion mutations linked with hepatocellular carcinoma (HCC). Ninety-three HCC patients and 108 non-HCC patients were enrolled for HBV genome-wide next-generation sequencing (NGS) analysis. A systematic literature review and a meta-analysis were performed to validate NGS-defined HCC-associated SNVs and deletions. The experimental results identified 60 NGS-defined HCC-associated SNVs, including 41 novel SNVs, and their pathogenic frequencies. Each SNV was specific for either genotype B (n = 24) or genotype C (n = 34), except for nt53C, which was present in both genotypes. The pathogenic frequencies of these HCC-associated SNVs showed a distinct U-shaped distribution pattern. According to the meta-analysis and literature review, 167 HBV variants from 109 publications were categorized into four levels (A-D) of supporting evidence that they are associated with HCC. The proportion of NGS-defined HCC-associated SNVs among these HBV variants declined significantly from 75% of 12 HCC-associated variants by meta-analysis (Level A) to 0% of 10 HCC-unassociated variants by meta-analysis (Level D) (P < 0.0001). PreS deletions were significantly associated with HCC, in terms of deletion index, for both genotypes B (P = 0.030) and C (P = 0.049). For genotype C, preS deletions involving a specific fragment (nt2977-3013) were significantly associated with HCC (HCC versus non-HCC, 6/34 versus 0/32, P = 0.025). Meta-analysis of preS deletions showed significant association with HCC (summary odds ratio 3.0; 95% confidence interval 2.3-3.9). Transfection of Huh7 cells showed that all of the five novel NGS-defined HCC-associated SNVs in the small surface region influenced hepatocarcinogenesis pathways, including endoplasmic reticulum-stress and DNA repair systems, as shown by microarray, real-time polymerase chain reaction and western blot analysis. Their carcinogenic mechanisms are worthy of further research. Copyright © 2017 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
Collapse
Affiliation(s)
- Wen-Chun Liu
- Department of Internal Medicine, National Cheng Kung University Hospital, College of Medicine, National Cheng Kung University, Tainan, Taiwan, ROC.,Infectious Disease and Signalling Research Centre, National Cheng Kung University, Tainan, Taiwan, ROC
| | - I-Chin Wu
- Department of Internal Medicine, National Cheng Kung University Hospital, College of Medicine, National Cheng Kung University, Tainan, Taiwan, ROC.,Infectious Disease and Signalling Research Centre, National Cheng Kung University, Tainan, Taiwan, ROC
| | - Yen-Chien Lee
- Department of Oncology, Tainan Hospital, Ministry of Health and Welfare, Tainan, Taiwan, ROC.,Institute of Clinical Medicine, College of Medicine, National Cheng Kung University, Tainan, Taiwan, ROC
| | | | - Ji-Hong Cheng
- Department of Computer Science and Information Engineering, National Cheng Kung University, Tainan, Taiwan, ROC
| | - Yih-Jyh Lin
- Department of Surgery, National Cheng Kung University College of Medicine and Hospital, Tainan, Taiwan, ROC
| | - Chia-Jui Yen
- Department of Internal Medicine, National Cheng Kung University Hospital, College of Medicine, National Cheng Kung University, Tainan, Taiwan, ROC.,Infectious Disease and Signalling Research Centre, National Cheng Kung University, Tainan, Taiwan, ROC
| | - Pin-Nan Cheng
- Department of Internal Medicine, National Cheng Kung University Hospital, College of Medicine, National Cheng Kung University, Tainan, Taiwan, ROC.,Infectious Disease and Signalling Research Centre, National Cheng Kung University, Tainan, Taiwan, ROC
| | - Pei-Fu Li
- Institute of Medical Informatics, National Cheng Kung University, Tainan, Taiwan, ROC
| | - Yi-Ting Cheng
- Institute of Medical Informatics, National Cheng Kung University, Tainan, Taiwan, ROC
| | - Pei-Wen Cheng
- Department of Information and Learning Technology, Science and Engineering College, National University of Tainan, Tainan, Taiwan, ROC
| | - Koun-Tem Sun
- Department of Information and Learning Technology, Science and Engineering College, National University of Tainan, Tainan, Taiwan, ROC
| | - Shu-Ling Yan
- Department of Internal Medicine, National Cheng Kung University Hospital, College of Medicine, National Cheng Kung University, Tainan, Taiwan, ROC
| | - Jia-Jhen Lin
- Department of Internal Medicine, National Cheng Kung University Hospital, College of Medicine, National Cheng Kung University, Tainan, Taiwan, ROC
| | - Jui-Chu Yang
- Human Biobank, Research Centre of Clinical Medicine, National Cheng Kung University Hospital, Tainan, Taiwan, ROC
| | - Kung-Chao Chang
- Human Biobank, Research Centre of Clinical Medicine, National Cheng Kung University Hospital, Tainan, Taiwan, ROC
| | - Cheng-Hsun Ho
- Department of Internal Medicine, National Cheng Kung University Hospital, College of Medicine, National Cheng Kung University, Tainan, Taiwan, ROC.,Infectious Disease and Signalling Research Centre, National Cheng Kung University, Tainan, Taiwan, ROC
| | - Vincent S Tseng
- Department of Computer Science, National Chiao Tung University, Hsinchu, Taiwan, ROC
| | | | - Jaw-Ching Wu
- Institute of Clinical Medicine, School of Medicine, National Yang-Ming University, Taipei, Taiwan, ROC.,Translational Research Division, Medical Research Department, Taipei Veterans General Hospital, Taipei, Taiwan, ROC
| | - Ting-Tsung Chang
- Department of Internal Medicine, National Cheng Kung University Hospital, College of Medicine, National Cheng Kung University, Tainan, Taiwan, ROC.,Infectious Disease and Signalling Research Centre, National Cheng Kung University, Tainan, Taiwan, ROC
| |
Collapse
|
4
|
Poortahmasebi V, Malekzadeh R, Montazeri G, Fakhari E, Norouzi M, Khamseh A, Mahmoodi Karkhaneh M, Tavakoli A, Jazayeri SM. Lamivudine Resistance and Precore Variants in Iranian Patients With Chronic Hepatitis B: Correlation With Virological and Clinical Features. Jundishapur J Microbiol 2015; 8:e20262. [PMID: 26487918 PMCID: PMC4609034 DOI: 10.5812/jjm.20262] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2014] [Revised: 09/22/2014] [Accepted: 12/28/2014] [Indexed: 01/10/2023] Open
Abstract
Background: Long-term lamivudine therapy, despite its initial effectiveness against hepatitis B virus (HBV), is associated with the emergence of drug resistance mutations in polymerase protein. Objectives: The aim of the present study was to determine the prevalence of precore and lamivudine drug resistance mutations in lamivudine treated patients with chronic B hepatitis. Patients and Methods: Sequential sera were obtained from 88 chronic HBV carriers who received lamivudine for more than 24 months. Polymerase and precore regions were directly sequenced for these groups: I (before treatment), II, and III (12 and 24 months after treatment, respectively). Results: All patients (100%) were contained genotype D, subtype ayw2. One (1.1%), 12 (13.6%), and 22 (25%) members of groups I, II, and III had the replacement of either isoleucine or valine instead of methionine in tyrosine-methionine-aspartate-aspartate (YMDD) motif, respectively. The frequency of mutations from 0 time point to 12 and 24 months showed that there was an increasing trend between sequential samples (P < 0.001). In group I, 31 (35.2%); II, 36 (41.0%) and III, 41 (46.6%) members had the precore stop codon mutations. The frequency of mutations from 0 time point to 12 and 24 months showed that there was an ascending trend between sequential samples. Indeed, frequency of precore stop codon was significantly increased with the passage of time (P < 0.001). Conclusions: Presence of drug resistance mutations among the patients was significant. Precore mutations were common amongst Iranian HBV chronic carriers under lamivudine therapy and these mutations were accompanied by clinical relapse.
Collapse
Affiliation(s)
- Vahdat Poortahmasebi
- Hepatitis B Molecular Laboratory, Department of Virology, School of Public Health, Tehran University of Medical Sciences, Tehran, IR Iran
| | - Reza Malekzadeh
- Digestive Disease Research Center, Shariati Hospital, Tehran, IR Iran
| | | | - Ehsan Fakhari
- Hepatitis B Molecular Laboratory, Department of Virology, School of Public Health, Tehran University of Medical Sciences, Tehran, IR Iran
| | - Mehdi Norouzi
- Hepatitis B Molecular Laboratory, Department of Virology, School of Public Health, Tehran University of Medical Sciences, Tehran, IR Iran
| | - Azam Khamseh
- Hepatitis B Molecular Laboratory, Department of Virology, School of Public Health, Tehran University of Medical Sciences, Tehran, IR Iran
| | - Masoud Mahmoodi Karkhaneh
- Hepatitis B Molecular Laboratory, Department of Virology, School of Public Health, Tehran University of Medical Sciences, Tehran, IR Iran
| | - Ahmad Tavakoli
- Hepatitis B Molecular Laboratory, Department of Virology, School of Public Health, Tehran University of Medical Sciences, Tehran, IR Iran
| | - Seyed Mohammad Jazayeri
- Hepatitis B Molecular Laboratory, Department of Virology, School of Public Health, Tehran University of Medical Sciences, Tehran, IR Iran
- Corresponding author: Seyed Mohammad Jazayeri, Hepatitis B Molecular Laboratory, Department of Virology, School of Public Health, Tehran University of Medical Sciences, Tehran, IR Iran. Tel: +98-2188950187, Fax: +98-2188954913, E-mail:
| |
Collapse
|
5
|
Baqai SF, Proudfoot J, Yi DH, Mangahas M, Gish RG. High rate of core promoter and precore mutations in patients with chronic hepatitis B. Hepatol Int 2014; 9:209-17. [PMID: 25788186 PMCID: PMC4387255 DOI: 10.1007/s12072-014-9598-5] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/21/2014] [Accepted: 12/03/2014] [Indexed: 12/14/2022]
Abstract
Background The prevalence of precore (PC) and core promoter (CP) mutations in patients with chronic hepatitis B virus (HBV) infection (CHB) and their impact on liver disease is incompletely defined in the United States. Methods A retrospective chart review using a cross-sectional approach of 1,186 CHB patients was conducted. Results Of 926 patients tested for HBV e antigen (HBeAg), 37 % were HBeAg+. Of 194 patients tested for mutations, 80 % had PC or CP mutations or both; 89 % of HBeAg-negative and 56 % of HBeAg+ patients had PC or CP mutations or both (p < 0.001). The mean log10 ALT was significantly lower in patients with both mutations compared to patients without mutations. The mean log10 HBV DNA was significantly lower in patients with only PC mutations (4.82) compared to patients without mutations (5.71, p = 0.019). With the study population divided into four subgroups based on ALT level at time of diagnosis, cirrhosis incidence was significantly higher in patients with ALT 1–2 × ULN and ALT > 2 × ULN compared to patients with ALT ≤ 0.5 × ULN. Conclusions Our finding that PC and CP mutations may be associated with milder liver disease in some patients could serve as the basis for longitudinal studies to help delineate treatment need and duration in patients with these mutations. If confirmed, the finding of an association between ALT 1–2 × ULN and increased incidence of cirrhosis could call into question guidelines which only recommend treatment with ALT > 2 × ULN.
Collapse
Affiliation(s)
- Sumbella F. Baqai
- Department of Internal Medicine, Alameda County Medical Center, 1411 E. 31st St., Oakland, CA 94602-1018 USA
| | - James Proudfoot
- Biostatistics Unit, Clinical and Translational Research Institute, University of California, San Diego, 9500 Gilman Drive, La Jolla, CA 92093 USA
| | - Debbie H. Yi
- Emergency Medicine and Neurocritical Care, Hospital of the University of Pennsylvania, 3400 Spruce St, Philadelphia, PA 19104 USA
| | - Michael Mangahas
- University of California, San Francisco/University of California, Berkeley, Joint Medical Program, University of California, San Francisco, School of Medicine, 513 Parnassus Avenue, San Francisco, CA 94143 USA
| | - Robert G. Gish
- Robert G. Gish Consultants, LLC, 6022 La Jolla Mesa Drive, San Diego, CA 92037 USA
- Department of Medicine, Division of Gastroenterology and Hepatology, Stanford University, 291 Campus Drive, Stanford, CA 94305 USA
- Hepatitis B Foundation, 3805 Old Easton Rd, Doylestown, PA 18902 USA
- St. Joseph’s Hospital and Medical Center, 350 W Thomas Road, Phoenix, AZ 85013 USA
- Department of Clinical Medicine, University of Nevada School of Medicine, 2040 West Charleston Boulevard, Las Vegas, NV 89102 USA
- Hepatitis B Foundation, 6022 La Jolla Mesa Drive, San Diego, CA 92037 USA
| |
Collapse
|
6
|
Odaibo GN, Ola SO, Olaleye OD. Hepatitis B virus DNA in patients with HBsAg in south western Nigeria. J Med Virol 2012; 85:214-8. [PMID: 23161583 DOI: 10.1002/jmv.23418] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/20/2012] [Indexed: 11/06/2022]
Abstract
There are about 400 million people with chronic hepatitis B virus (HBV) infection worldwide with a potential of adverse sequelae including hepatocellular carcinoma. Recent data have shown that the level of HBV DNA in serum or plasma of an infected person probably reflects more accurately the replicative activity of the virus and therefore may serve as a better maker for management of the infection. This study was designed to determine the rate of detection of HBV DNA in blood samples of patients with HBsAg positive in Nigeria in comparison with the HBe and anti-HBe used widely as serological markers of infectivity. Plasma samples from 105 patients with HBsAg positive were tested for the presence of HBeAg and anti-HBe using a commercial enzyme-linked immunosorbent assay while plasma HBV DNA was quantified using the COBAS Amplicor HBV Monitor assay. Of the 105 HBsAg samples, 17 (16.2%) and 85 (81%) were positive for HBeAg and anti-HBe, respectively, while 8 (7.6%) were negative for both HBeAg and anti-HBe. HBV DNA was detected in 86 (81.9%) of the samples, out of which 15 (18.1%) and 67 (80.7%) were positive for HBeAg and anti-HBe, respectively. HBV DNA was detected in 78.4% of the HBeAg negative samples and in all the eight samples that were negative for both HBeAg and anti-HBe. The implication of these findings in the management of patients with HBV infection is compelling.
Collapse
Affiliation(s)
- Georgina N Odaibo
- Department of Virology, University College Hospital, University of Ibadan, Ibadan, Nigeria.
| | | | | |
Collapse
|
7
|
Jiang S, Yang Z, Li W, Li X, Wang Y, Zhang J, Xu C, Chen PJ, Hou J, McCrae MA, Chen X, Zhuang H, Lu F. Re-evaluation of the carcinogenic significance of hepatitis B virus integration in hepatocarcinogenesis. PLoS One 2012; 7:e40363. [PMID: 22962577 PMCID: PMC3433482 DOI: 10.1371/journal.pone.0040363] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2012] [Accepted: 06/05/2012] [Indexed: 12/17/2022] Open
Abstract
To examine the role of hepatitis B virus (HBV) integration in hepatocarcinogenesis, a systematic comparative study of both tumor and their corresponding non-tumor derived tissue has been conducted in a cohort of 60 HBV associated hepatocellular carcinoma (HCC) patients. By using Alu-polymerase chain reaction (PCR) and ligation-mediated PCR, 233 viral-host junctions mapped across all human chromosomes at random, no difference between tumor and non-tumor tissue was observed, with the exception of fragile sites (P = 0.0070). HBV insertions in close proximity to cancer related genes such as hTERT were found in this study, however overall they were rare events. No direct correlation between chromosome aberrations and the number of HBV integration events was found using a sensitive array-based comparative genomic hybridization (aCGH) assay. However, a positive correlation was observed between the status of several tumor suppressor genes (TP53, RB1, CDNK2A and TP73) and the number of chromosome aberrations (r = 0.6625, P = 0.0003). Examination of the viral genome revealed that 43% of inserts were in the preC/C region and 57% were in the HBV X gene. Strikingly, approximately 24% of the integrations examined had a breakpoint in a short 15 nt viral genome region (1820-1834 nt). As a consequence, all of the confirmed X gene insertions were C-terminal truncated, losing their growth-suppressive domain. However, the same pattern of X gene C-terminal truncation was found in both tumor and non-tumor derived samples. Furthermore, the integrated viral sequences in both groups had a similar low frequency of C1653T, T1753V and A1762T/G1764A mutations. The frequency and patterns of HBV insertions were similar between tumor and their adjacent non-tumor samples indicating that the majority of HBV DNA integration events are not associated with hepatocarcinogenesis.
Collapse
Affiliation(s)
- Suzhen Jiang
- Department of Microbiology, School of Basic Medical Sciences, Peking University Health Science Center, Beijing, Beijing, China
- Department of Infectious Disease, Nanfang Hospital, Southern Medical University, Guangzhou, Guangdong, China
- Department of Infectious Disease, Linyi People's Hospital, Linyi, Shandong, China
| | - Ziwei Yang
- Department of Microbiology, School of Basic Medical Sciences, Peking University Health Science Center, Beijing, Beijing, China
| | - Weijie Li
- Department of Microbiology, School of Basic Medical Sciences, Peking University Health Science Center, Beijing, Beijing, China
| | - Xiaojun Li
- Department of Microbiology, School of Basic Medical Sciences, Peking University Health Science Center, Beijing, Beijing, China
| | - Yongfeng Wang
- Department of Microbiology, School of Basic Medical Sciences, Peking University Health Science Center, Beijing, Beijing, China
| | - Jiangbo Zhang
- Department of Microbiology, School of Basic Medical Sciences, Peking University Health Science Center, Beijing, Beijing, China
| | - Chunhui Xu
- Department of Microbiology, School of Basic Medical Sciences, Peking University Health Science Center, Beijing, Beijing, China
| | - Pei-Jer Chen
- Hepatitis Research Center, National Taiwan University and Hospital, Taipei, Taiwan
| | - Jinlin Hou
- Department of Infectious Disease, Nanfang Hospital, Southern Medical University, Guangzhou, Guangdong, China
| | - Malcolm A. McCrae
- Department of Biological Sciences, University of Warwick, Coventry, United Kingdom
| | - Xiangmei Chen
- Department of Microbiology, School of Basic Medical Sciences, Peking University Health Science Center, Beijing, Beijing, China
- Infectious Disease Center, Peking University, Beijing, China
- * E-mail: (XMC); Lu.fengmin @hsc.pku.edu.cn (FML)
| | - Hui Zhuang
- Department of Microbiology, School of Basic Medical Sciences, Peking University Health Science Center, Beijing, Beijing, China
- Infectious Disease Center, Peking University, Beijing, China
| | - Fengmin Lu
- Department of Microbiology, School of Basic Medical Sciences, Peking University Health Science Center, Beijing, Beijing, China
- Infectious Disease Center, Peking University, Beijing, China
- * E-mail: (XMC); Lu.fengmin @hsc.pku.edu.cn (FML)
| |
Collapse
|
8
|
Chung GE, Kim W, Lee JH, Kim YJ, Yoon JH, Lee JM, Lee JY, Kim SH, Kim D, Lee HS. Negative hepatitis B envelope antigen predicts intrahepatic recurrence in hepatitis B virus-related hepatocellular carcinoma after ablation therapy. J Gastroenterol Hepatol 2011; 26:1638-45. [PMID: 22011297 DOI: 10.1111/j.1440-1746.2011.06777.x] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
BACKGROUND AND AIM Patients with persistently active hepatitis B virus (HBV) replication are at high risk for progression to liver cirrhosis and hepatocellular carcinoma (HCC). The influence of the viral load of HBV on intrahepatic recurrence after local ablation therapy in patients with HBV-related HCC has not been elucidated. We aimed to evaluate predictors of intrahepatic recurrence and clarify the correlation between viral load and intrahepatic recurrence after percutaneous ablation. METHODS Patients with HBV-related, solitary HCC undergoing radiofrequency ablation (RFA) or percutaneous ethanol injection (PEI), between October 2004 and December 2008 were prospectively enrolled. Statistical analyses were performed using the Kaplan-Meier method and Cox regression model to identify risk factors for intrahepatic recurrence. RESULTS A total of 145 patients (male, 81.4%; mean age, 55.3 years) were included. Ninety patients (62.1%) had serum HBV DNA ≥2000 IU/mL. The median follow-up duration was 28.9 months (range, 12.0-57.0) and 63 patients (43.4%) experienced intrahepatic tumor recurrence. Multivariate analysis indicated that seropositivity for hepatitis B envelope antigen (HBeAg) was an independent negative predictor of intrahepatic recurrence (hazard ratio, 0.473; P=0.026) and late (≥1 year) recurrence (HR, 0.288; P=0.012). The serum alpha fetoprotein (AFP) level also significantly predicted late recurrence (HR, 1.001; P=0.005). However, neither the ablation method nor serum HBV DNA titers were correlated with intrahepatic recurrence. CONCLUSIONS These findings show that HBeAg-negativity and serum AFP levels were associated with late intrahepatic recurrence of HCC, implicating HBeAg-negativity as a risk factor for de novo recurrence after percutaneous ablation in HBV-related HCC.
Collapse
Affiliation(s)
- Goh Eun Chung
- Department of Internal Medicine, Healthcare Research Institute, Seoul National University Hospital Healthcare System Gangnam Center, Seoul, Korea
| | | | | | | | | | | | | | | | | | | |
Collapse
|
9
|
Ahn SH, Yuen L, Han KH, Littlejohn M, Chang HY, Damerow H, Ayres A, Heo J, Locarnini S, Revill PA. Molecular and clinical characteristics of hepatitis B virus in Korea. J Med Virol 2010; 82:1126-34. [PMID: 20513074 DOI: 10.1002/jmv.21844] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
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.
Collapse
Affiliation(s)
- Sang Hoon Ahn
- Department of Internal Medicine, Institute of Gastroenterology, Yonsei University College of Medicine, Seoul, Republic of Korea
| | | | | | | | | | | | | | | | | | | |
Collapse
|
10
|
Vartanian JP, Henry M, Marchio A, Suspène R, Aynaud MM, Guétard D, Cervantes-Gonzalez M, Battiston C, Mazzaferro V, Pineau P, Dejean A, Wain-Hobson S. Massive APOBEC3 editing of hepatitis B viral DNA in cirrhosis. PLoS Pathog 2010; 6:e1000928. [PMID: 20523896 PMCID: PMC2877740 DOI: 10.1371/journal.ppat.1000928] [Citation(s) in RCA: 136] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2010] [Accepted: 04/27/2010] [Indexed: 12/13/2022] Open
Abstract
DNA viruses, retroviruses and hepadnaviruses, such as hepatitis B virus (HBV), are vulnerable to genetic editing of single stranded DNA by host cell APOBEC3 (A3) cytidine deaminases. At least three A3 genes are up regulated by interferon-α in human hepatocytes while ectopic expression of activation induced deaminase (AICDA), an A3 paralog, has been noted in a variety of chronic inflammatory syndromes including hepatitis C virus infection. Yet virtually all studies of HBV editing have confined themselves to analyses of virions from culture supernatants or serum where the frequency of edited genomes is generally low (≤10−2). We decided to look at the nature and frequency of HBV editing in cirrhotic samples taken during removal of a primary hepatocellular carcinoma. Forty-one cirrhotic tissue samples (10 alcoholic, 10 HBV+, 11 HBV+HCV+ and 10 HCV+) as well as 4 normal livers were studied. Compared to normal liver, 5/7 APOBEC3 genes were significantly up regulated in the order: HCV±HBV>HBV>alcoholic cirrhosis. A3C and A3D were up regulated for all groups while the interferon inducible A3G was over expressed in virus associated cirrhosis, as was AICDA in ∼50% of these HBV/HCV samples. While AICDA can indeed edit HBV DNA ex vivo, A3G is the dominant deaminase in vivo with up to 35% of HBV genomes being edited. Despite these highly deleterious mutant spectra, a small fraction of genomes survive and contribute to loss of HBeAg antigenemia and possibly HBsAg immune escape. In conclusion, the cytokine storm associated with chronic inflammatory responses to HBV and HCV clearly up regulates a number of A3 genes with A3G clearly being a major restriction factor for HBV. Although the mutant spectrum resulting from A3 editing is highly deleterious, a very small part, notably the lightly edited genomes, might help the virus evolve and even escape immune responses. Retroviruses and hepadnaviruses such as hepatitis B virus (HBV) are vulnerable to mutation by host cell single stranded DNA cytidine deaminases. The result is hypermutated viral peppered with uracil residues. While there are potentially 11 such human enzymes, the major players belong to the 7 gene APOBEC3 cluster on chromosome 22, some of which can be activated by anti-viral interferons. We investigated the nature and frequency of HBV editing in 41 cirrhotic samples following surgical removal of primary hepatocellular carcinoma. Numerous APOBEC3 genes were activated in the decreasing order HCV±HBV>HBV>alcoholic cirrhosis. We observed that APOBEC3G was the dominant restricting factor in vivo with up to 35% of HBV edited genomes. Among the HBV mutants generated by APOBEC3 editing, we found a small fraction of lightly APOBEC3G edited genomes that can impact HBV replication in vivo and possibly immune escape.
Collapse
|
11
|
Chen CH, Changchien CS, Lee CM, Hung CH, Hu TH, Wang JH, Wang JC, Lu SN. Combined mutations in pre-s/surface and core promoter/precore regions of hepatitis B virus increase the risk of hepatocellular carcinoma: a case-control study. J Infect Dis 2008; 198:1634-42. [PMID: 18939932 DOI: 10.1086/592990] [Citation(s) in RCA: 91] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
BACKGROUND We sought to investigate the role of sequence variations in pre-S/surface and basal core promoter (BCP)/precore regions of the hepatitis B virus (HBV) in hepatocellular carcinoma (HCC). METHODS The direct sequencing in pre-S/surface and BCP/precore regions of HBV was determined for 80 patients with HCC and 160 control patients with HBV infection. RESULTS Compared with control patients, patients with HCC had higher frequencies of pre-S deletions and amino acid substitutions at codon 4, 7, and 81 in pre-S1 genes; at the start codon in pre-S2 genes; and at codon 68 in surface genes. Patients also had a lower frequency of amino acid substitution at codon 2 in pre-S2 genes, compared with control patients. In BCP/precore regions, patients with HCC had higher frequencies of C or G1753, A1762/T1764, T1846, and A1899. Multivariate analysis showed that pre-S deletions, I68T surface gene, T1762/A1764, and A1899 were independent factors associated with the development of HCC. The HBV strain with a complex mutation pattern rather than a single mutation was associated with HCC, and the HCC risks increased for patients having these factors in combination. CONCLUSIONS Pre-S deletions, I68T in surface gene, T1762/A1764, and A1899 were independent risk factors for HCC. Combination of these viral mutations appeared to increase the risk of HCC.
Collapse
Affiliation(s)
- Chien-Hung Chen
- Division of Hepatogastroenterology, Department of Internal Medicine, Chang Gung Memorial Hospital-Kaohsiung Medical Center, Chang Gung University College of Medicine, 123 Ta Pei Road, Kaohsiung, Taiwan
| | | | | | | | | | | | | | | |
Collapse
|
12
|
Chauhan R, Kazim SN, Kumar M, Bhattacharjee J, Krishnamoorthy N, Sarin SK. Identification and characterization of genotype A and D recombinant hepatitis B virus from Indian chronic HBV isolates. World J Gastroenterol 2008; 14:6228-36. [PMID: 18985816 PMCID: PMC2761587 DOI: 10.3748/wjg.14.6228] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
AIM: To confirm the presence of recombination, full-length hepatitis B virus (HBV) from chronic patients was sequenced and analyzed.
METHODS: Full-length HBV genomes from 12 patients were amplified and sequenced in an automated sequencer. Phylogenetic analysis was carried out on full-length, Core and preS2/Surface regions using MEGA software. SimPlot Boot Scanning and amino acid sequence analysis were performed for confirmation of recombination.
RESULTS: Eight patients were infected with genotype D strain; one patient with genotype A and three patients had genotype A and D recombination; two of them had cirrhosis and one had hepatocellular carcinoma. Phylogenetic analysis of core and preS2/surface regions separately showed evidence of genotype A and D recombination. The breakpoints of recombination were found to be at the start of preS2 and at the end of surface coding regions.
CONCLUSION: We identified and characterized recombinant A and D genotype HBV in hepatitis B surface antigen (HBsAg)-positive patients.
Collapse
|
13
|
Chauhan R, Kazim SN, Bhattacharjee J, Sakhuja P, Sarin SK. Basal core promoter, precore region mutations of HBV and their association with e antigen, genotype, and severity of liver disease in patients with chronic hepatitis B in India. J Med Virol 2006; 78:1047-54. [PMID: 16789012 DOI: 10.1002/jmv.20661] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Spontaneous mutations of hepatitis B virus (HBV) could influence the severity of liver disease. Since the basal core promoter (BCP) and the precore (Pc) regions are important for viral replication, these regions were examined for naturally occurring mutations and were correlated with the genotype, e antigen status, and severity of liver disease. In 82 patients with histologically confirmed chronic hepatitis B, the BCP and Pc regions were sequenced and aligned with known wild-type sequences. Sequence based HBV genotyping was done and HBV DNA was quantified. Thirty-three (40%) patients had decompensated chronic liver disease and the remaining patients had chronic hepatitis B. Forty-six (56%) patients were HBeAg positive. HBV genotype A was found in 28%, D in 65%, and B/C in 7.3%. The Pc G1896A mutation was more common in HBeAg-negative (33% vs. 2%, P < 0.01) patients and was genotype D specific. The Pc G1862T mutation was detected more often in HBeAg-positive than HBeAg-negative (37% vs. 11%, P < 0.01) patients and was genotype A specific (P < 0.01). BCP mutations at the 1,762/64 nucleotide positions were common in HBeAg negative than positive (36% vs. 13%, P < 0.05) and were equally common in different genotypes. TA 1-3 region mutations of the BCP were significantly higher in HBeAg-negative as compared to HBeAg-positive patients (78% vs. 26%, P < 0.01). BCP mutations had significantly higher HBV DNA levels. It is concluded that Pc G1862T mutant is Genotype A-specific but is not always associated with e antigen. The TA 1-3 rich mutations of BCP region are also associated with the absence of e antigen in Indian patients.
Collapse
Affiliation(s)
- Ranjit Chauhan
- Department of Gastroenterology, and Advanced Center for Liver Diseases, G.B. Pant Hospital, New Delhi, India
| | | | | | | | | |
Collapse
|
14
|
Bonilla Guerrero R, Roberts LR. The role of hepatitis B virus integrations in the pathogenesis of human hepatocellular carcinoma. J Hepatol 2005; 42:760-77. [PMID: 15826727 DOI: 10.1016/j.jhep.2005.02.005] [Citation(s) in RCA: 150] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Affiliation(s)
- Ruben Bonilla Guerrero
- Center for Basic Research in Digestive Diseases, Division of Gastroenterology and Hepatology and Mayo Clinic Cancer Center, Mayo Clinic College of Medicine, 200 First Street SW, Rochester, MN 55905, USA
| | | |
Collapse
|
15
|
Yang HZ, Zhao JA, Dai M, Li YW, Wang YZ, Guan WB, Xie HP. Traditional Chinese medicine syndromes of chronic hepatitis B with precore mutant. World J Gastroenterol 2005; 11:2004-8. [PMID: 15800995 PMCID: PMC4305726 DOI: 10.3748/wjg.v11.i13.2004] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
AIM: This study aims at exploring the distribution of TCM syndromes in CHB patients with HBV pre-core mutation (1896) and the relationship between pre-core mutation and T lymphocytes subgroup, through which to provide objective data on clinical syndrome differentiation of TCM, and further to suggest the therapeutic principle and guide clinical treatment.
METHODS: One hundred and forty CHB patients were evenly divided into two study groups, HBV pre-core mutant group and HBV pre-core wild-type group. Besides, 30 healthy blood donors were selected as a healthy control group. HBV-labeled compound, T lymphocytes subgroup, and HBV-DNA pre-core mutant were tested in the study groups. T lymphocytes subgroup were also tested in the control group. All the patients were both diagnosed by syndrome differentiation of TCM and western medicine.
RESULTS: The most common syndrome in mutant group was damp-heat combined with blood stasis, and the most common syndrome in the wild-type group was damp-heat stasis in the middle-jiao. There were more cases of medium and severe hepatitis in mutant group than that in wild-type group. The content of CD4+ lymphocytes and CD4+/CD8+ ratio were decreased gradually (healthy control group>wild-type group>mutant group). In the wild-type group, severe and medium CHB patients had considerably lower level of them than mild CHB patients. However, in the mutant group, the opposite result appeared. Meanwhile, the content of HBV-DNA in mutant group was higher than that in wild-type group.
CONCLUSION: Damp, heat, toxin and blood stasis were the basic pathogens of CHB, whether pre-core mutant or not. CHB with precore mutant may lead to more severe hepatitis. The decreased content of CD4+ lymphocytes and ratio of CD4+/CD8+ may be taken as one of the indices in confirming the deficiency syndrome of CHB patients with pre-core mutation.
Collapse
Affiliation(s)
- Hong-Zhi Yang
- Department of Traditional Chinese Medicine, The Third Affiliated Hospital of Sun Yat-Sen University, Guangzhou 510630, Guangdong Province, China.
| | | | | | | | | | | | | |
Collapse
|
16
|
|
17
|
Chu CJ, Keeffe EB, Han SH, Perrillo RP, Min AD, Soldevila-Pico C, Carey W, Brown RS, Luketic VA, Terrault N, Lok ASF. Prevalence of HBV precore/core promoter variants in the United States. Hepatology 2003; 38:619-28. [PMID: 12939588 DOI: 10.1053/jhep.2003.50352] [Citation(s) in RCA: 171] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Variants in the precore (G(1896)A) and core promoter (A(1762)T, G(1764)A) regions of hepatitis B virus (HBV) may be related to serum HBV DNA levels and severity of liver disease. The aims of this nationwide study were to determine the prevalence of HBV precore/core promoter variants in the United States and the association between these variants and patient demographics, HBV genotypes, serum HBV DNA level, and severity of liver disease. A total of 694 consecutive chronic HBV-infected patients seen in 17 U.S. liver centers during a 1-year period were enrolled. Demographic, clinical, and laboratory data were collected. Sera were tested for HBV genotypes as well as precore and core promoter variants by line-probe assays. Quantitative HBV DNA levels were determined using Cobas Amplicor HBV Monitor kits. Precore and core promoter variants were found in 27% and 44% of patients with chronic HBV infection in the United States. Precore and core promoter variants were more common in hepatitis B e antigen (HBeAg)-negative than in HBeAg-positive patients (precore, 38% vs. 9%; core promoter, 51% vs. 36%; respectively, P <.001). The prevalence of these variants was related to ethnicity, place of birth, and HBV genotypes. Patients with core promoter variants were more likely to have hepatic decompensation. Precore and/or core promoter variants were associated with higher serum HBV DNA levels in HBeAg-negative but not in HBeAg-positive patients. In conclusion, HBV precore and core promoter variants are not rare in the United States. Physicians should be aware of the existence of HBV precore and core promoter variants and the clinical condition of "HBeAg-negative chronic hepatitis."
Collapse
Affiliation(s)
- Chi-Jen Chu
- Division of Gastroenterology, University of Michigan, Ann Arbor, MI, USA
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
18
|
Hassoun Z, Gores GJ. What surgeons should know about viral hepatitis and hepatocellular carcinoma. Surg Oncol Clin N Am 2003; 12:1-11, vii. [PMID: 12735125 DOI: 10.1016/s1055-3207(02)00081-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Most patients with hepatocellular carcinoma (HCC) have viral hepatitis, either hepatitis C (HCV) or hepatitis B (HBV). HCV is an RNA virus that does not integrate into the host genome but likely induces HCC through viral protein: for example, host protein interactions or via the inflammatory response to the virus. Eradication of HCV with interferon plus riboviron therapy may help prevent cancer recurrence in selected patients. In contrast to HCV, HBV is an DNA virus that integrates into the host genome, and this integration is believed, in part, to be carcinogenic. HBV is usually classified as replicative (DNA-positive in the serum) or nonreplicative (DNA-negative in the serum). Treatment with nucleoside analogs is indicated in most patients with cirrhotic-stage replicating HBV. Nonreplicative stages of this virus do not merit therapy with these agents.
Collapse
Affiliation(s)
- Ziad Hassoun
- Division of Gastroenterology and Hepatology, Mayo Medical School, Clinic, and Foundation, 200 First Street SW, Rochester, MN 55905, USA
| | | |
Collapse
|
19
|
Affiliation(s)
- Wei Ning Chen
- Department of Clinical Research, Singapore General Hospital, Singapore
| | | |
Collapse
|
20
|
Chan HLY, Tsang SWC, Liew CT, Tse CH, Wong ML, Ching JYL, Leung NWY, Tam JSL, Sung JJY. Viral genotype and hepatitis B virus DNA levels are correlated with histological liver damage in HBeAg-negative chronic hepatitis B virus infection. Am J Gastroenterol 2002; 97:406-12. [PMID: 11866280 DOI: 10.1111/j.1572-0241.2002.05478.x] [Citation(s) in RCA: 117] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
OBJECTIVES We aimed to study the relationship between the hepatitis B virus (HBV) genotypes, core promoter/precore stop codon mutations, and histological liver damage among hepatitis B e antigen (HBeAg)-negative patients. METHODS Liver biopsy specimens of 55 HBeAg-negative chronic HBV-infected patients were studied. A histological activity index was scored for degree of necroinflammation (HAI-NI) and fibrosis (HAI-F) as described by Knodell et al. HBV DNA was determined by a cross-linking assay and polymerase chain reaction (PCR) at the core promoter/precore region and the S region. PCR-positive samples were directly sequenced for core promoter and precore mutations and examined by restriction fragment length polymorphism for genotyping. RESULTS Forty-one males and 14 females at a median age of 43 were studied. HBV DNA was detectable in 32 (58%) and 37 (67%) patients by the cross-linking assay and PCR, respectively, at the time of liver biopsy. The median (range) HAI-NI and HAI-F scores were 5 (1-10) and 2 (0-4), respectively. HBV DNA detectable by either the cross-linking assay or PCR was associated with a higher HAI-NI score. Eleven and 31 patients had genotypes B and C HBV, respectively. Genotype C HBV was associated with higher HAI-NI than genotype B HBV. Core promoter mutations and precore stop codon mutation were detected in 74% and 40% patients, respectively, but they were not associated with higher HAI-NI or HAI-F scores. CONCLUSIONS Detectable HBV DNA and genotype C HBV, but not core promoter or precore stop codon mutations, are associated with more severe liver damage in HBeAg-negative patients.
Collapse
|
21
|
Abstract
Hepatitis B virus (HBV) is at the origin of severe liver diseases like chronic active hepatitis, liver cirrhosis and hepatocellular carcinoma. There are some groups of patients with high risk of generation of HBV mutants: infected infants, immunosuppressed individuals (including hemodialysis patients), patients treated with interferon and lamivudine for chronic HBV infection. These groups are the target for molecular investigations reviewed in this paper. The emergence of lamivudine- or other antiviral-resistant variants, rises concern regarding long term use of these drugs. Infection or immunization with one HBV subtype confers immunity to all subtypes. However, reinfection or reactivation of latent HBV infection with HBV mutants have been reported in patients undergoing transplant and those infected with HIV. Mutations of the viral genome which are not replicative incompetent can be selected in further course of infection or under prolonged antiviral treatment and might maintain the liver disease. Four open reading frames (ORF) which are called S-gene, C-gene, X-gene and P-gene were identified within the HBV genome. Mutations may affect each of the ORFs. Mutated S-genes were described to be responsible for HBV-infections in successfully vaccinated persons, mutated C-genes were found to provoke severe chronic liver diseases, mutated X-genes could cause serious medical problems in blood donors by escaping the conventional test systems and mutated P-genes were considered to be the reason for chemotherapeutic drug resistance. This paper reviews molecular, immunological and clinical aspects of the HBV mutants.
Collapse
Affiliation(s)
- C Kreutz
- International Technology for Evaluation of Clinical Pharmacology, Paris, France.
| |
Collapse
|
22
|
Kew MC. Hepatitis B virus in the etiology of hepatocellular carcinoma. VIRUSES AND LIVER CANCER 2002. [DOI: 10.1016/s0168-7069(02)06063-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
|
23
|
Abstract
Chronic hepatitis B virus (HBV) infection is a major global cause of hepatocellular carcinoma (HCC). Individuals who are chronic carriers have a greater than 100-fold increased relative risk of developing the tumour. Several mechanisms of HBV-induced HCC have been proposed. Integration of HBV DNA into the genome of hepatocytes occurs commonly, although integration at cellular sites that are important for regulation of hepatocyte proliferation appears to be a rare event. Functions of the HBx protein are also potentially oncogenic. These include transcriptional activation of cellular growth regulatory genes, modulation of apoptosis and inhibition of nucleotide excision repair of damaged cellular DNA. The effects of HBx are mediated by interaction with cellular proteins and activation of cell signalling pathways. Variations in HBV genome sequences may be important in hepatocarcinogenesis, although their significance has not yet been completely elucidated. Necroinflammatory hepatic disease, which often accompanies chronic HBV infection, may contribute indirectly to hepatocyte transformation in a number of ways, including by facilitating HBV DNA integration, predisposing to the acquisition of cellular mutations and generating mutagenic oxygen reactive species. Although HCC is a malignancy with a poor prognosis, the availability of an effective vaccine against HBV infection, and its inclusion in the Expanded Programme of Immunization of many countries, augurs well for the eventual elimination of HBV-associated HCC.
Collapse
Affiliation(s)
- P Arbuthnot
- Department of Molecular Medicine and Haematology and Molecular Hepatology Research Unit, Department of Medicine, University of the Witwatersrand Medical School, 7 York Road, Parktown 2193, South Africa
| | | |
Collapse
|
24
|
Lee YS, Yoon SJ, Kwon TK, Kim YH, Woo JH, Suh MH, Suh SI, Baek WK, Kim HJ, Ahn SY, Choe BK, Park JW. Immune response induced by immunization with Hepatitis B virus core DNA isolated from chronic active hepatitis patients. Immunol Lett 2001; 78:13-20. [PMID: 11470146 DOI: 10.1016/s0165-2478(01)00230-9] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
There are many mutations in the gene encoding Hepatitis B virus (HBV) core antigen of chronic active hepatitis patients, and such mutations are most likely to be related to the severity of disease. Here, we constructed plasmids containing wild-type and deletion type of HBV core gene (HBc) to develop an experimental DNA vaccine and to compare immunogenicity of two types of HBc vaccine. Twenty-nine wild-types and seven deletion types of HBc were detected in sera of 32 Korean patients with chronic active hepatitis. Four wild-types (W1, W2, W4, W6) and two deletion types (D3, D4) of HBc were cloned into the pcDNA3 vector. Intramuscular immunization with wild-type HBc efficiently increased serum anti-HBc antibody response in a dose-dependent manner. Anti-HBc antibody response in mice injected with W6 increased 14 days after immunization, and peaked after 30 days and was maintained at least up to 50 days. W6 immunization induced a specific cytotoxic T lymphocyte response to W6-transfected 3LL (3LL-W6), and reduced the sizes of tumor mass of mice challenged with 3LL-W6 or 3LL transfected with D4. However, intramuscular immunization with D3 and D4 did not show antibody response at all. D3 and D4 have 157 bp (from 331 to 491 bp) and 122 bp (from 327 to 448 bp) gene deletion, respectively, and these encode class II MHC-restricted T-cell epitope. Altogether, these results suggest that mutant virus that has deleted HBc gene may evade immune systems due to loss of T-cell epitope.
Collapse
MESH Headings
- Animals
- DNA, Viral/administration & dosage
- Disease Models, Animal
- Gene Deletion
- Hepatitis B Antibodies/analysis
- Hepatitis B Antibodies/biosynthesis
- Hepatitis B Core Antigens/administration & dosage
- Hepatitis B Core Antigens/genetics
- Hepatitis B Core Antigens/immunology
- Hepatitis B virus/genetics
- Hepatitis B virus/immunology
- Hepatitis B, Chronic/immunology
- Hepatitis B, Chronic/prevention & control
- Hepatitis B, Chronic/virology
- Humans
- Injections, Intramuscular
- Male
- Mice
- Mice, Inbred BALB C
- Neoplasm Transplantation
- Plasmids
- T-Lymphocytes, Cytotoxic/immunology
- Time Factors
- Tumor Cells, Cultured
- Vaccination
- Vaccines, DNA/administration & dosage
Collapse
Affiliation(s)
- Y S Lee
- Department of Immunology, School of Medicine, Keimyung University, 194 Dong San-Dong Jung-Gu, Taegu 700-712, South Korea
| | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
25
|
Abstract
Chronic hepatitis B virus (HBV) infection is a major global cause of hepatocellular carcinoma (HCC). Individuals who are chronic carriers have a greater than 100-fold increased relative risk of developing the tumour. Several mechanisms of HBV-induced HCC have been proposed. Integration of HBV DNA into the genome of hepatocytes occurs commonly, although integration at cellular sites that are important for regulation of hepatocyte proliferation appears to be a rare event. Functions of the HBx protein are also potentially oncogenic. These include transcriptional activation of cellular growth regulatory genes, modulation of apoptosis and inhibition of nucleotide excision repair of damaged cellular DNA. The effects of HBx are mediated by interaction with cellular proteins and activation of cell signalling pathways. Variations in HBV genome sequences may be important in hepatocarcinogenesis, although their significance has not yet been completely elucidated. Necroinflammatory hepatic disease, which often accompanies chronic HBV infection, may contribute indirectly to hepatocyte transformation in a number of ways, including by facilitating HBV DNA integration, predisposing to the acquisition of cellular mutations and generating mutagenic oxygen reactive species. Although HCC is a malignancy with a poor prognosis, the availability of an effective vaccine against HBV infection, and its inclusion in the Expanded Programme of Immunization of many countries, augurs well for the eventual elimination of HBV-associated HCC.
Collapse
Affiliation(s)
- Patrick Arbuthnot
- Department of Molecular Medicine and Haematology, University of the Witwatersrand Medical School7 York Road, Parktown 2193, South Africa
- Molecular Hepatology Research Unit, Department of Medicine, University of the Witwatersrand Medical School7 York Road, Parktown 2193, South Africa
| | - Michael Kew
- Molecular Hepatology Research Unit, Department of Medicine, University of the Witwatersrand Medical School7 York Road, Parktown 2193, South Africa
| |
Collapse
|