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Yuan SY, Yu HB, Yang Z, Qin YP, Ren JH, Cheng ST, Ren F, Law BYK, Wong VKW, Ng JPL, Zhou YJ, He X, Tan M, Zhang ZZ, Chen J. Pimobendan Inhibits HBV Transcription and Replication by Suppressing HBV Promoters Activity. Front Pharmacol 2022; 13:837115. [PMID: 35721154 PMCID: PMC9204083 DOI: 10.3389/fphar.2022.837115] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2021] [Accepted: 05/10/2022] [Indexed: 12/03/2022] Open
Abstract
Current anti-HBV therapeutic strategy relies on interferon and nucleos(t)ide-type drugs with the limitation of functional cure, inducing hepatitis B surface antigen (HBsAg) loss in very few patients. Notably, the level of HBsAg has been established as an accurate indicator to evaluate the drug efficacy and predict the disease prognosis, thus exploring a novel drug targeting HBsAg will be of great significance. Herein, by screening 978 compounds from an FDA-approved drug library and determining the inhibitory function of each drug on HBsAg level in HepG2.2.15 cells supernatant, we identified that pimobendan (Pim) has a powerful antiviral activity with relatively low cytotoxicity. The inhibitory effect of Pim on HBsAg as well as other HBV markers was validated in HBV-infected cell models and HBV-transgenic mice. Mechanistically, real-time PCR and dual-luciferase reporter assay were applied to identify the partial correlation of transcription factor CAAT enhancer-binding protein α (C/EBPα) with the cccDNA transcription regulated by Pim. This indicates Pim is an inhibitor of HBV transcription through suppressing HBV promoters to reduce HBV RNAs levels and HBsAg production. In conclusion, Pim was identified to be a transcription inhibitor of cccDNA, thereby inhibiting HBsAg and other HBV replicative intermediates both in vitro and in vivo. This report may provide a promising lead for the development of new anti-HBV agent.
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Affiliation(s)
- Si-Yu Yuan
- The Key Laboratory of Molecular Biology of Infectious Diseases Designated by the Chinese Ministry of Education, Chongqing Medical University, Chongqing, China
| | - Hai-Bo Yu
- The Key Laboratory of Molecular Biology of Infectious Diseases Designated by the Chinese Ministry of Education, Chongqing Medical University, Chongqing, China
| | - Zhen Yang
- The Key Laboratory of Molecular Biology of Infectious Diseases Designated by the Chinese Ministry of Education, Chongqing Medical University, Chongqing, China
| | - Yi-Ping Qin
- The Key Laboratory of Molecular Biology of Infectious Diseases Designated by the Chinese Ministry of Education, Chongqing Medical University, Chongqing, China
| | - Ji-Hua Ren
- The Key Laboratory of Molecular Biology of Infectious Diseases Designated by the Chinese Ministry of Education, Chongqing Medical University, Chongqing, China
| | - Sheng-Tao Cheng
- The Key Laboratory of Molecular Biology of Infectious Diseases Designated by the Chinese Ministry of Education, Chongqing Medical University, Chongqing, China
| | - Fang Ren
- The Key Laboratory of Molecular Biology of Infectious Diseases Designated by the Chinese Ministry of Education, Chongqing Medical University, Chongqing, China
| | - Betty Yuen Kwan Law
- State Key Laboratory of Quality Research in Chinese Medicine, Macau University of Science and Technology, Macao, China
| | - Vincent Kam Wai Wong
- State Key Laboratory of Quality Research in Chinese Medicine, Macau University of Science and Technology, Macao, China
| | - Jerome P. L. Ng
- State Key Laboratory of Quality Research in Chinese Medicine, Macau University of Science and Technology, Macao, China
| | - Yu-Jiao Zhou
- The Key Laboratory of Molecular Biology of Infectious Diseases Designated by the Chinese Ministry of Education, Chongqing Medical University, Chongqing, China
| | - Xin He
- The Key Laboratory of Molecular Biology of Infectious Diseases Designated by the Chinese Ministry of Education, Chongqing Medical University, Chongqing, China
| | - Ming Tan
- The Key Laboratory of Molecular Biology of Infectious Diseases Designated by the Chinese Ministry of Education, Chongqing Medical University, Chongqing, China
| | - Zhen-Zhen Zhang
- Chongqing Key Laboratory of Child Infection and Immunity, Ministry of Education Key Laboratory of Child Development and Disorders, National Clinical Research Center for Child Health and Disorders, Department of Infectious Diseases, The Children’s Hospital of Chongqing Medical University, Chongqing, China
- *Correspondence: Zhen-Zhen Zhang, ; Juan Chen,
| | - Juan Chen
- The Key Laboratory of Molecular Biology of Infectious Diseases Designated by the Chinese Ministry of Education, Chongqing Medical University, Chongqing, China
- *Correspondence: Zhen-Zhen Zhang, ; Juan Chen,
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Abstract
Hepatitis B virus (HBV) is a hepatotropic virus and an important human pathogen. There are an estimated 296 million people in the world that are chronically infected by this virus, and many of them will develop severe liver diseases including hepatitis, cirrhosis and hepatocellular carcinoma (HCC). HBV is a small DNA virus that replicates via the reverse transcription pathway. In this review, we summarize the molecular pathways that govern the replication of HBV and its interactions with host cells. We also discuss viral and non-viral factors that are associated with HBV-induced carcinogenesis and pathogenesis, as well as the role of host immune responses in HBV persistence and liver pathogenesis.
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Affiliation(s)
- Yu-Chen Chuang
- Department of Molecular Microbiology and Immunology, University of Southern California Keck School of Medicine, Los Angeles, CA 90089, USA
| | - Kuen-Nan Tsai
- Department of Molecular Microbiology and Immunology, University of Southern California Keck School of Medicine, Los Angeles, CA 90089, USA
| | - Jing-Hsiung James Ou
- Department of Molecular Microbiology and Immunology, University of Southern California Keck School of Medicine, Los Angeles, CA 90089, USA
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Host Transcription Factors in Hepatitis B Virus RNA Synthesis. Viruses 2020; 12:v12020160. [PMID: 32019103 PMCID: PMC7077322 DOI: 10.3390/v12020160] [Citation(s) in RCA: 40] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2019] [Revised: 01/27/2020] [Accepted: 01/28/2020] [Indexed: 02/06/2023] Open
Abstract
The hepatitis B virus (HBV) chronically infects over 250 million people worldwide and is one of the leading causes of liver cancer and hepatocellular carcinoma. HBV persistence is due in part to the highly stable HBV minichromosome or HBV covalently closed circular DNA (cccDNA) that resides in the nucleus. As HBV replication requires the help of host transcription factors to replicate, focusing on host protein–HBV genome interactions may reveal insights into new drug targets against cccDNA. The structural details on such complexes, however, remain poorly defined. In this review, the current literature regarding host transcription factors’ interactions with HBV cccDNA is discussed.
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Immunopathogenesis of HBV Infection. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2019; 1179:71-107. [DOI: 10.1007/978-981-13-9151-4_4] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
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HoxA10 Facilitates SHP-1-Catalyzed Dephosphorylation of p38 MAPK/STAT3 To Repress Hepatitis B Virus Replication by a Feedback Regulatory Mechanism. J Virol 2019; 93:JVI.01607-18. [PMID: 30674631 DOI: 10.1128/jvi.01607-18] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2018] [Accepted: 01/17/2019] [Indexed: 02/07/2023] Open
Abstract
Hepatitis B virus (HBV) infection is the leading cause of chronic hepatitis B (CHB), liver cirrhosis (LC), and hepatocellular carcinoma (HCC). This study reveals a distinct mechanism underlying the regulation of HBV replication. HBV activates homeobox A10 (HoxA10) in human hepatocytes, leukocytes, peripheral blood mononuclear cells (PBMCs), HepG2-NTCP cells, leukocytes isolated from CHB patients, and HBV-associated HCC tissues. HoxA10 in turn represses HBV replication in human hepatocytes, HepG2-NTCP cells, and BALB/c mice. Interestingly, we show that during early HBV infection, p38 mitogen-activated protein kinase (MAPK) and signal transducer and activator of transcription 3 (STAT3) were activated to facilitate HBV replication; however, during late HBV infection, HoxA10 was induced to attenuate HBV replication. Detailed studies reveal that HoxA10 binds to p38 MAPK, recruits SH2-containing protein tyrosine phosphatase 1 (SHP-1) to facilitate SHP-1 in catalyzing dephosphorylation of p38 MAPK/STAT3, and thereby attenuates p38 MAPK/STAT3 activation and HBV replication. Furthermore, HoxA10 binds to the HBV enhancer element I (EnhI)/X promoter, competes with STAT3 for binding of the promoter, and thereby represses HBV transcription. Taken together, these results show that HoxA10 attenuates HBV replication through repressing the p38 MAPK/STAT3 pathway by two approaches: HoxA10 interacts with p38 MAPK and recruits SHP-1 to repress HBV replication, and HoxA10 binds to the EnhI/X promoter and competes with STAT3 to attenuate HBV transcription. Thus, the function of HoxA10 is similar to the action of interferon (IFN) in terms of inhibition of HBV infection; however, the mechanism of HoxA10-mediated repression of HBV replication is different from the mechanism underlying IFN-induced inhibition of HBV infection.IMPORTANCE Two billion people have been infected with HBV worldwide; about 240 million infected patients developed chronic hepatitis B (CHB), and 650,000 die each year from liver cirrhosis (LC) or hepatocellular carcinoma (HCC). This work elucidates a mechanism underlying the control of HBV replication. HBV infection activates HoxA10, a regulator of cell differentiation and cancer progression, in human cells and patients with CHB and HCC. HoxA10 subsequently inhibits HBV replication in human tissue culture cells and mice. Additionally, HoxA10 interacts with p38 MAPK to repress the activation of p38 MAPK and STAT3 and recruits and facilitates SHP-1 to catalyze the dephosphorylation of p38 MAPK and STAT3. Moreover, HoxA10 competes with STAT3 for binding of the HBV X promoter to repress HBV transcription. Thus, this work reveals a negative regulatory mechanism underlying the control of HBV replication and provides new insights into the development of potential agents to control HBV infection.
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Hao R, Xiang K, Shi Y, Zhao D, Tian H, Xu B, Zhu Y, Dong H, Ding H, Zhuang H, Hu J, Li T. Naturally Occurring Mutations within HBV Surface Promoter II Sequences Affect Transcription Activity, HBsAg and HBV DNA Levels in HBeAg-Positive Chronic Hepatitis B Patients. Viruses 2019; 11:v11010078. [PMID: 30669266 PMCID: PMC6356792 DOI: 10.3390/v11010078] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2018] [Revised: 01/13/2019] [Accepted: 01/15/2019] [Indexed: 02/07/2023] Open
Abstract
Mutations in hepatitis B virus (HBV) surface promoter II (SPII) have not been well studied in hepatitis B e antigen (HBeAg)-positive chronic hepatitis B (CHB) patients. We aimed to investigate SPII mutations in such patients and their biological and clinical impacts. Direct sequencing was used to detect SPII mutations in 106 HBeAg-positive treatment-naïve CHB patients with genotype C (82.1% (87/106) was C2) HBV infection. Results showed that mutation frequency in transcription factor (TF) unbinding region was significantly higher than that in TF binding region of SPII (C1: 3.4% vs. 1.3%; C2: 2.6% vs. 1.3%; p < 0.0001). Luciferase assay revealed distinct promoter activities among SPII mutants; especially SPII of G120A mutant had a 15-fold higher activity than that of wild-type (p < 0.001). In vitro experiments in HepG2 cells showed that G82A, A115C and G120A mutants increased the hepatitis B surface antigen (HBsAg) levels, while C18T had an opposite effect. G82A, A115C and G120A mutants boosted the intracellular HBV total RNA level. G120A mutation resulted in an increased HBV DNA level in vitro, consistent with the serological results in patients. Thus, novel SPII mutations would affect promoter activity, HBsAg, HBV DNA and HBV total RNA levels, suggesting their potential biological and clinical significances.
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Affiliation(s)
- Ran Hao
- School of Nursing, Hebei Medical University, Shijiazhuang 050000, Hebei, China.
| | - Kuanhui Xiang
- Department of Microbiology and Infectious Disease Center, School of Basic Medical Sciences, Peking University Health Science Center, Beijing 100191, China.
| | - Yan Shi
- Institute of Microbiology, Shijiazhuang Center for Disease Control and Prevention, Shijiazhuang 050000, Hebei, China.
| | - Dong Zhao
- Institute of Microbiology, Shijiazhuang Center for Disease Control and Prevention, Shijiazhuang 050000, Hebei, China.
| | - Huifang Tian
- Institute of Microbiology, Shijiazhuang Center for Disease Control and Prevention, Shijiazhuang 050000, Hebei, China.
| | - Baohong Xu
- Institute of Microbiology, Shijiazhuang Center for Disease Control and Prevention, Shijiazhuang 050000, Hebei, China.
| | - Yufang Zhu
- School of Nursing, Hebei Medical University, Shijiazhuang 050000, Hebei, China.
| | - Huan Dong
- School of Nursing, Hebei Medical University, Shijiazhuang 050000, Hebei, China.
| | - Hai Ding
- Hunan Sansure Biotech Incorporation, Lusong Road, Changsha 410000, Hunan, China.
| | - Hui Zhuang
- Department of Microbiology and Infectious Disease Center, School of Basic Medical Sciences, Peking University Health Science Center, Beijing 100191, China.
| | - Jie Hu
- School of Nursing, Hebei Medical University, Shijiazhuang 050000, Hebei, China.
| | - Tong Li
- Department of Microbiology and Infectious Disease Center, School of Basic Medical Sciences, Peking University Health Science Center, Beijing 100191, China.
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Sagnelli E, Potenza N, Onorato L, Sagnelli C, Coppola N, Russo A. Micro-RNAs in hepatitis B virus-related chronic liver diseases and hepatocellular carcinoma. World J Hepatol 2018; 10:558-570. [PMID: 30310534 PMCID: PMC6177563 DOI: 10.4254/wjh.v10.i9.558] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/27/2018] [Revised: 04/24/2018] [Accepted: 05/31/2018] [Indexed: 02/06/2023] Open
Abstract
MicroRNAs (miRNAs) are small non-coding RNAs that modulate gene expression at the post-transcriptional level by affecting both the stability and translation of complementary mRNAs. Several studies have shown that miRNAs are important regulators in the conflicting efforts between the virus (to manipulate the host for its successful propagation) and the host (to inhibit the virus), culminating in either the elimination of the virus or its persistence. An increasing number of studies report a role of miRNAs in hepatitis B virus (HBV) replication and pathogenesis. In fact, HBV is able to modulate different host miRNAs, particularly through the transcriptional transactivator HBx protein and, conversely, different cellular miRNAs can regulate HBV gene expression and replication by a direct binding to HBV transcripts or indirectly targeting host factors. The present review will discuss the role of miRNAs in the pathogenesis of HBV-related diseases and their role as a biomarker in the management of patients with HBV-related disease and as therapeutic targets.
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Affiliation(s)
- Evangelista Sagnelli
- Department of Mental Health and Public Medicine, Section of Infectious Diseases, University of Campania Luigi Vanvitelli, Naples 80135, Italy
| | - Nicoletta Potenza
- DISTABIF, University of Campania “Luigi Vanvitelli”, Naples 80100, Italy
| | - Lorenzo Onorato
- Department of Mental Health and Public Medicine, Section of Infectious Diseases, University of Campania Luigi Vanvitelli, Naples 80135, Italy
| | - Caterina Sagnelli
- Department of Mental Health and Public Medicine, Section of Infectious Diseases, University of Campania Luigi Vanvitelli, Naples 80135, Italy
| | - Nicola Coppola
- Department of Mental Health and Public Medicine, Section of Infectious Diseases, University of Campania Luigi Vanvitelli, Naples 80135, Italy
| | - Aniello Russo
- DISTABIF, University of Campania “Luigi Vanvitelli”, Naples 80100, Italy
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8
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Wu CC, Chen YS, Cao L, Chen XW, Lu MJ. Hepatitis B virus infection: Defective surface antigen expression and pathogenesis. World J Gastroenterol 2018; 24:3488-3499. [PMID: 30131655 PMCID: PMC6102499 DOI: 10.3748/wjg.v24.i31.3488] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/03/2018] [Revised: 06/01/2018] [Accepted: 06/25/2018] [Indexed: 02/06/2023] Open
Abstract
Hepatitis B virus (HBV) infection is a global public health concern. HBV causes chronic infection in patients and can lead to liver cirrhosis, hepatocellular carcinoma, and other severe liver diseases. Thus, understanding HBV-related pathogenesis is of particular importance for prevention and clinical intervention. HBV surface antigens are indispensable for HBV virion formation and are useful viral markers for diagnosis and clinical assessment. During chronic HBV infection, HBV genomes may acquire and accumulate mutations and deletions, leading to the expression of defective HBV surface antigens. These defective HBV surface antigens have been found to play important roles in the progression of HBV-associated liver diseases. In this review, we focus our discussion on the nature of defective HBV surface antigen mutations and their contribution to the pathogenesis of fulminant hepatitis B. The relationship between defective surface antigens and occult HBV infection are also discussed.
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MESH Headings
- DNA, Viral/genetics
- DNA, Viral/isolation & purification
- Disease Progression
- Genome, Viral/genetics
- Hepatitis B Surface Antigens/genetics
- Hepatitis B Surface Antigens/immunology
- Hepatitis B Surface Antigens/metabolism
- Hepatitis B virus/genetics
- Hepatitis B virus/immunology
- Hepatitis B, Chronic/immunology
- Hepatitis B, Chronic/pathology
- Hepatitis B, Chronic/prevention & control
- Hepatitis B, Chronic/virology
- Humans
- Liver/immunology
- Liver/pathology
- Liver/virology
- Liver Failure, Acute/immunology
- Liver Failure, Acute/pathology
- Liver Failure, Acute/prevention & control
- Liver Failure, Acute/virology
- Mutation
- Virus Replication/genetics
- Virus Replication/immunology
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Affiliation(s)
- Chun-Chen Wu
- State Key Laboratory of Virology, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan 430071, Hubei Province, China
| | - Ying-Shan Chen
- State Key Laboratory of Virology, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan 430071, Hubei Province, China
| | - Liang Cao
- State Key Laboratory of Virology, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan 430071, Hubei Province, China
- Department of Microbiology and Immunology, Feinberg School of Medicine Northwestern University, Chicago, IL 60611, United States
| | - Xin-Wen Chen
- State Key Laboratory of Virology, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan 430071, Hubei Province, China
| | - Meng-Ji Lu
- Institute of Virology, University Hospital of Essen, Essen 45122, Germany
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Xu L, Wu Z, Tan S, Wang Z, Lin Q, Li X, Song X, Liu Y, Song Y, Zhang J, Peng J, Gao L, Gong Y, Liang X, Zuo X, Ma C. Tumor suppressor ZHX2 restricts hepatitis B virus replication via epigenetic and non-epigenetic manners. Antiviral Res 2018; 153:114-123. [DOI: 10.1016/j.antiviral.2018.03.008] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2017] [Revised: 03/14/2018] [Accepted: 03/22/2018] [Indexed: 01/10/2023]
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10
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TIP60 Complex Inhibits Hepatitis B Virus Transcription. J Virol 2018; 92:JVI.01788-17. [PMID: 29321313 DOI: 10.1128/jvi.01788-17] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2017] [Accepted: 01/02/2018] [Indexed: 02/07/2023] Open
Abstract
Hepatitis B virus (HBV) is a global major health problem, with over one million deaths annually caused by chronic liver damage. Understanding host factors that modulate HBV replication may aid the development of anti-HBV therapies. Our recent genome-wide small interfering RNA screen using recombinant HBV demonstrated that TIP60 inhibited HBV infection. Here, we show that TIP60 complex contributes to anti-HBV defense. The TIP60 complex bound to the HBV promoter and suppressed HBV transcription driven by the precore/core promoter. The silencing of EP400, TRRAP, BAF53a, RUVBL1, and RUVBL2, which form the TIP60 complex, also resulted in increased HBV transcription. These results contribute to our enhanced understanding of the molecular mechanism of HBV transcription associated with the chromatin structure of HBV covalently closed circular DNA (cccDNA). Exploiting these intrinsic cellular defenses might help develop new anti-HBV agents.IMPORTANCE Investigating the molecular mechanism of HBV replication is important to understand the persistent nature of HBV infection and to aid the development of new HBV agents, which are currently limited to HBV polymerase inhibitors. Previously, we developed a new reporter HBV. By screening host factors using this recombinant virus, we identified several gene products that regulate HBV infection, including TIP60. Here, we showed that TIP60, a catalytic subunit of the NuA4 complex, inhibited HBV replication. Depletion of TIP60 increased the level of HBV mRNA. Moreover, TIP60 localized in the HBV cccDNA chromatin complex catalyzed the acetylation of histone H4 to recruit Brd4. These results suggest that TIP60, in concert with other cellular factors, plays an important role in the regulation of the HBV chromatin structure by acting as a critical component of the intrinsic antiviral defense, which sheds new light on the regulation of HBV replication.
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Li-Shuai Q, Yu-Yan C, Hai-Feng Z, Jin-Xia L, Cui-Hua L. Pre-S deletions of hepatitis B virus predict recurrence of hepatocellular carcinoma after curative resection. Medicine (Baltimore) 2017; 96:e8311. [PMID: 29069001 PMCID: PMC5671834 DOI: 10.1097/md.0000000000008311] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
The relationship between hepatitis B virus (HBV) and the prognosis of hepatocellular carcinoma (HCC) after surgery remains uncertain. A retrospective cohort study was performed to evaluate the impact of pre-S deletions, T1762/A1764, and A1896 mutations on prognosis of HCC after curative resection. A total of 113 patients with positive serum HBV DNA (>200 IU/mL) who had underwent curative resection of pathologically proven HCC were recruited to determine the risk factors affecting the prognosis.The median follow-up time was 36.5 months and recurrence was detected in 67 patients (59.3%). The cumulative recurrence rates and overall survival rates at 1-, 3-, and 5-year after curative resection were 18.0%, 49.7%, 70.3%, and 93.7%, 61.0%, 42.5%, respectively. Patients with pre-S deletions showed significantly higher recurrence rates compared with those with wild type infection (HR: 1.822, P = .018), but not related with a significantly poor survival (HR: 1.388, P = .235). Subgroup analysis indicated that the patients with type III deletion had significant higher tumor recurrence rates than other deletion types (HR: 2.211, 95% confidence intervals [CI]: 1.008-4.846, P = .048). Multivariate analysis revealed that pre-S deletion, tumor size >3 cm in diameter, and the presence of microvascular invasion were independent risk factors for tumor recurrence. HBV pre-S deletions were found to be clustered primarily in the 5' end of pre-S2 region and were more often found between amino acids 120 and 142 of the pre-S2 domain. The domains most frequently potentially involved were the transactivator domain in pre-S2 and polymerized human serum albumin binding site.Our cohort showed that pre-S deletions at the time of resection could predict tumor recurrence in HCC patients after curative resection.
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Affiliation(s)
| | | | - Zhang Hai-Feng
- Department of Infectious Disease, Affiliated Hospital of Nantong University, Jiangsu, China
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12
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Functional association of cellular microtubules with viral capsid assembly supports efficient hepatitis B virus replication. Sci Rep 2017; 7:10620. [PMID: 28878350 PMCID: PMC5587681 DOI: 10.1038/s41598-017-11015-4] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2017] [Accepted: 08/18/2017] [Indexed: 12/23/2022] Open
Abstract
Viruses exploit host factors and environment for their efficient replication. The virus-host interaction mechanisms for achieving an optimal hepatitis B virus (HBV) replication have been largely unknown. Here, a single cell cloning revealed that HepAD38 cells, a widely-used HBV-inducible cell line, contain cell clones with diverse permissiveness to HBV replication. The HBV permissiveness was impaired upon treatment with microtubule inhibitor nocodazole, which was identified as an HBV replication inhibitor from a pharmacological screening. In the microtubule-disrupted cells, the efficiency of HBV capsid assembly was remarkably decreased without significant change in pre-assembly process. We further found that HBV core interacted with tubulin and co-localized with microtubule-like fibriforms, but this association was abrogated upon microtubule-disassembly agents, resulting in attenuation of capsid formation. Our data thus suggest a significant role of microtubules in the efficient capsid formation during HBV replication. In line with this, a highly HBV permissive cell clone of HepAD38 cells showed a prominent association of core-microtubule and thus a high capacity to support the capsid formation. These findings provide a new aspect of virus-cell interaction for rendering efficient HBV replication.
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13
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Hensel KO, Rendon JC, Navas MC, Rots MG, Postberg J. Virus-host interplay in hepatitis B virus infection and epigenetic treatment strategies. FEBS J 2017; 284:3550-3572. [PMID: 28457020 DOI: 10.1111/febs.14094] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2017] [Revised: 03/25/2017] [Accepted: 04/26/2017] [Indexed: 12/11/2022]
Abstract
Worldwide, chronic hepatitis B virus (HBV) infection is a major health problem and no cure exists. Importantly, hepatocyte intrusion by HBV particles results in a complex deregulation of both viral and host cellular genetic and epigenetic processes. Among the attempts to develop novel therapeutic approaches against HBV infection, several options targeting the epigenomic regulation of HBV replication are gaining attention. These include the experimental treatment with 'epidrugs'. Moreover, as a targeted approach, the principle of 'epigenetic editing' recently is being exploited to control viral replication. Silencing of HBV by specific rewriting of epigenetic marks might diminish viral replication, viremia, and infectivity, eventually controlling the disease and its complications. Additionally, epigenetic editing can be used as an experimental tool to increase our limited understanding regarding the role of epigenetic modifications in viral infections. Aiming for permanent epigenetic reprogramming of the viral genome without unspecific side effects, this breakthrough may pave the roads for an ambitious technological pursuit: to start designing a curative approach utilizing manipulative molecular therapies for viral infections in vivo.
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Affiliation(s)
- Kai O Hensel
- HELIOS Medical Centre Wuppertal, Paediatrics Centre, Centre for Clinical & Translational Research (CCTR), Faculty of Health, Centre for Biomedical Education & Research (ZBAF), Witten/Herdecke University, Germany
| | - Julio C Rendon
- Epigenetic Editing, Department of Pathology and Medical Biology, University of Groningen, University Medical Center Groningen (UMCG), The Netherlands.,Grupo de Gastrohepatologia, Facultad de Medicina, Universidad de Antioquia (UdeA), Medellin, Colombia
| | - Maria-Cristina Navas
- Grupo de Gastrohepatologia, Facultad de Medicina, Universidad de Antioquia (UdeA), Medellin, Colombia
| | - Marianne G Rots
- Epigenetic Editing, Department of Pathology and Medical Biology, University of Groningen, University Medical Center Groningen (UMCG), The Netherlands
| | - Jan Postberg
- HELIOS Medical Centre Wuppertal, Paediatrics Centre, Centre for Clinical & Translational Research (CCTR), Faculty of Health, Centre for Biomedical Education & Research (ZBAF), Witten/Herdecke University, Germany
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14
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Chen BF. Different pre-S deletion patterns and their association with hepatitis B virus genotypes. World J Gastroenterol 2017. [PMID: 27672298 DOI: 10.3748/wjg.v22.i35.8041.] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 09/29/2022] Open
Abstract
AIM To investigate the associations of different types of pre-S deletions with hepatitis B virus (HBV) genotypes. METHODS The sequences of the pre-S region, basal core promoter (BCP) mutation, and precore (PC) mutation were examined through direct DNA sequencing or clonal analysis and sequencing in 273 HBV carriers, namely 55 asymptomatic carriers, 55 carriers with chronic hepatitis (CH), 55 with liver cirrhosis (LC), 53 with liver cirrhotic hepatocellular carcinoma (LC-HCC), and 55 with noncirrhotic HCC. A total of 126 HBV carriers (46.2%) harbored pre-S deletions. The DNA sequences of pre-S deletion mutants from 43 age-matched genotype B (HBV/B)-infected carriers and 43 age-matched genotype C (HBV/C)-infected carriers were further examined, aligned, and compared. RESULTS No significant difference was observed in the mean age distribution (P = 0.464), male sex (P = 0.805), viral load (P = 0.635), or BCP mutation (P = 0.117) between the HBV/B and HBV/C groups. However, the rate of PC mutation was significantly higher in the HBV/B-infected carriers than in the HBV/C-infected carriers (P = 0.003). Both genotypes exhibited a high rate of deletion in the C-terminal half of the pre-S1 region and N-terminus of the pre-S2 region (86.0% and 79.1% in the HBV/B group; 69.8% and 72.1% in the HBV/C group, respectively). Epitope mapping showed that deletion in several epitope sites was frequent in both genotypes, particularly pS1-BT and pS2-B2. Conversely, the rate of pS2-B1 deletion was significantly higher in the HBV/B group (72.1% vs 37.2%, P = 0.002), and the rate of pS2-T deletion was significantly higher in the HBV/C group (48.8% vs 25.6%, P = 0.044). Functional mapping showed that the rate of deletion in three functional sites (the nucleocapsid binding site, start codon of M, and site for viral secretion) located in the N-terminus of the pre-S2 region was significantly higher in the HBV/B group (P < 0.05). One type of N-terminus pre-S1 deletion mutant with deletion of the start codon of the L protein was frequently observed in the HBV/C group (20.9% vs 9.3%, P = 0.228), particularly in the LC patients (42.9% vs 12.5%). Different patterns of pre-S deletions were also found between the HBV/B and HBV/C groups according to different clinical outcomes. In CH patients, deletion in the site for polymerized human serum albumin was more frequent in the HBV/B group (88.9% vs 36.4%, P = 0.028). In the LC-HCC patients, the rate of deletion in the pre-S2 region was significantly higher in the HBV/B group than in the HBV/C group (P < 0.05). CONCLUSION HBV/B- and HBV/C-infected carriers exhibit different patterns of pre-S deletion, which may be associated with the progression of liver diseases.
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Affiliation(s)
- Bing-Fang Chen
- Bing-Fang Chen, School of Medicine, Fu Jen Catholic University, New Taipei City 24205, Taiwan
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Zhang F, Tang X, Garcia T, Lok AS, Wang Y, Jia H, Qin Y, Chen C, Wen Y, Li J, Tong S. Characterization of contrasting features between hepatitis B virus genotype A and genotype D in small envelope protein expression and surface antigen secretion. Virology 2017; 503:52-61. [PMID: 28126637 DOI: 10.1016/j.virol.2017.01.009] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2016] [Revised: 01/14/2017] [Accepted: 01/17/2017] [Indexed: 12/18/2022]
Abstract
Hepatitis B virus (HBV) genotypes A and D are prevalent in many parts of the world and show overlapping geographic distributions. We amplified the entire HBV genome from sera of patients with genotypes A and D and generated overlength constructs for transient transfection into Huh7 or HepG2 cells. Genotype D clones were associated with less HBsAg in culture supernatant and even less intracellular HBsAg. They produced less 2.1-kb RNA due to a weaker SPII promoter. Chimeric promoter constructs identified three divergent positions as most critical, and their exchange reversed extracellular HBsAg phenotype. The S protein of genotype D was more efficient at secretion, while its L protein possessed greater inhibitory effect. Swapping the S gene diminished genotypic difference in intracellular S protein but widened the difference in secreted HBsAg. In conclusion, HBV genotypes A and D differ in S protein expression, secretion and modulation by L protein.
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Affiliation(s)
- Fei Zhang
- Key Lab of Medical Molecular Virology, School of Basic Medical Sciences, Fudan University, Shanghai, China
| | - Xiaoli Tang
- Liver Research Center, Rhode Island Hospital, Warren Alpert School of Medicine, Brown University, Providence, RI, USA
| | - Tamako Garcia
- Liver Research Center, Rhode Island Hospital, Warren Alpert School of Medicine, Brown University, Providence, RI, USA
| | - Anna S Lok
- Division of Gastroenterology and Hepatology, University of Michigan, Ann Arbor, MI, USA
| | - Yongxiang Wang
- Key Lab of Medical Molecular Virology, School of Basic Medical Sciences, Fudan University, Shanghai, China
| | - Haodi Jia
- Key Lab of Medical Molecular Virology, School of Basic Medical Sciences, Fudan University, Shanghai, China
| | - Yanli Qin
- Department of Infectious Diseases, Huashan Hospital, Fudan University, Shanghai, China
| | - Chaoyang Chen
- Key Lab of Medical Molecular Virology, School of Basic Medical Sciences, Fudan University, Shanghai, China
| | - Yumei Wen
- Key Lab of Medical Molecular Virology, School of Basic Medical Sciences, Fudan University, Shanghai, China
| | - Jisu Li
- Liver Research Center, Rhode Island Hospital, Warren Alpert School of Medicine, Brown University, Providence, RI, USA
| | - Shuping Tong
- Key Lab of Medical Molecular Virology, School of Basic Medical Sciences, Fudan University, Shanghai, China; Liver Research Center, Rhode Island Hospital, Warren Alpert School of Medicine, Brown University, Providence, RI, USA.
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16
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Identification of a new hepatitis B virus recombinant D2/D3 in the city of São Paulo, Brazil. Arch Virol 2016; 162:457-467. [PMID: 27787680 DOI: 10.1007/s00705-016-3122-2] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2016] [Accepted: 10/13/2016] [Indexed: 02/07/2023]
Abstract
Two hundred forty million people are chronically infected with hepatitis B virus (HBV) worldwide. The rise of globalization has facilitated the emergence of novel HBV recombinants and genotypes. We evaluated HBV genotypes and recombinants, mutations associated with resistance to antivirals (AVs), progression of hepatic illness, and inefficient hepatitis B vaccination responses in chronically infected individuals in the city of São Paulo, Brazil. Forty-five full-length and 24 partial-length sequences were obtained. The genotype distribution was as follows: A (66.7%), D (15.9%), F (11.6%) and C (4.3%). We describe a new recombinant (D2/D3), confirmed through next-generation sequencing (NGS) and reconstruction of the quasispecies sequences in silico. Primary resistance and major vaccine escape mutations were not found. We did, however, find mutations in the S region that might may be related to HBV antigenicity changes, as well as Pre-S deletions. The precore/core mutations A1762T + G1764A (40.9%) were found mostly in genotypes A and D, and G1896A (29.55%) was more frequent in genotype D than in genotype A. The genotypic distribution reflects the history of Brazilian immigration. This is the first description of recombination between genotypes D2 and D3 in Brazil. It is also the first confirmation through NGS and reconstruction of the quasispecies in silico. However, little is known about the response to treatment of recombinants. This demonstrates the need for molecular epidemiology studies involving the analysis of full-length HBV sequences.
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Chen BF. Different pre-S deletion patterns and their association with hepatitis B virus genotypes. World J Gastroenterol 2016; 22:8041-8049. [PMID: 27672298 PMCID: PMC5028817 DOI: 10.3748/wjg.v22.i35.8041] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/09/2016] [Revised: 07/24/2016] [Accepted: 08/08/2016] [Indexed: 02/06/2023] Open
Abstract
AIM To investigate the associations of different types of pre-S deletions with hepatitis B virus (HBV) genotypes.
METHODS The sequences of the pre-S region, basal core promoter (BCP) mutation, and precore (PC) mutation were examined through direct DNA sequencing or clonal analysis and sequencing in 273 HBV carriers, namely 55 asymptomatic carriers, 55 carriers with chronic hepatitis (CH), 55 with liver cirrhosis (LC), 53 with liver cirrhotic hepatocellular carcinoma (LC-HCC), and 55 with noncirrhotic HCC. A total of 126 HBV carriers (46.2%) harbored pre-S deletions. The DNA sequences of pre-S deletion mutants from 43 age-matched genotype B (HBV/B)-infected carriers and 43 age-matched genotype C (HBV/C)-infected carriers were further examined, aligned, and compared.
RESULTS No significant difference was observed in the mean age distribution (P = 0.464), male sex (P = 0.805), viral load (P = 0.635), or BCP mutation (P = 0.117) between the HBV/B and HBV/C groups. However, the rate of PC mutation was significantly higher in the HBV/B-infected carriers than in the HBV/C-infected carriers (P = 0.003). Both genotypes exhibited a high rate of deletion in the C-terminal half of the pre-S1 region and N-terminus of the pre-S2 region (86.0% and 79.1% in the HBV/B group; 69.8% and 72.1% in the HBV/C group, respectively). Epitope mapping showed that deletion in several epitope sites was frequent in both genotypes, particularly pS1-BT and pS2-B2. Conversely, the rate of pS2-B1 deletion was significantly higher in the HBV/B group (72.1% vs 37.2%, P = 0.002), and the rate of pS2-T deletion was significantly higher in the HBV/C group (48.8% vs 25.6%, P = 0.044). Functional mapping showed that the rate of deletion in three functional sites (the nucleocapsid binding site, start codon of M, and site for viral secretion) located in the N-terminus of the pre-S2 region was significantly higher in the HBV/B group (P < 0.05). One type of N-terminus pre-S1 deletion mutant with deletion of the start codon of the L protein was frequently observed in the HBV/C group (20.9% vs 9.3%, P = 0.228), particularly in the LC patients (42.9% vs 12.5%). Different patterns of pre-S deletions were also found between the HBV/B and HBV/C groups according to different clinical outcomes. In CH patients, deletion in the site for polymerized human serum albumin was more frequent in the HBV/B group (88.9% vs 36.4%, P = 0.028). In the LC-HCC patients, the rate of deletion in the pre-S2 region was significantly higher in the HBV/B group than in the HBV/C group (P < 0.05).
CONCLUSION HBV/B- and HBV/C-infected carriers exhibit different patterns of pre-S deletion, which may be associated with the progression of liver diseases.
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Li X, Qin Y, Liu Y, Li F, Liao H, Lu S, Qiao Y, Xu D, Li J. PreS deletion profiles of hepatitis B virus (HBV) are associated with clinical presentations of chronic HBV infection. J Clin Virol 2016; 82:27-32. [PMID: 27415434 DOI: 10.1016/j.jcv.2016.06.018] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2016] [Revised: 06/20/2016] [Accepted: 06/28/2016] [Indexed: 12/21/2022]
Abstract
BACKGROUND The association of hepatitis B virus (HBV) preS1 and preS2 deletions with progressive liver diseases are not fully understood. OBJECTIVE The study aimed to investigate characteristics of HBV preS deletion in HBV-infected patients with different illness categories. STUDY DESIGN Total of 539 HBV-infected patients were enrolled in the study, including 146 with chronic hepatitis B (CHB), 111 with HBV-related liver cirrhosis (LC), 146 with HBV-related acute-on-chronic liver failure (ACLF), and 136 with HBV-related hepatocellular carcinoma (HCC). PreS deletion was determined by sequencing. Replicons containing representative preS1 and preS2 deletion mutants and wild-type were respectively constructed and transfected into HepG2 cells for phenotypic analysis. RESULTS The detection rates of overall preS deletion were 15.8%, 26.1%, 24.0%, and 34.6% in CHB, LC, ACLF, and HCC patients, respectively. PreS1 deletion was most frequently detected in LC patients while preS2 deletion was most frequently detected in HCC patients, both frequencies were significantly higher than that in CHB patients (17.1% vs. 4.8%, P<0.01; 19.1% vs. 4.8%, P<0.01). The deletion patterns across preS gene were different among the 4 illness categories. Compared with wild-type strain, the preS1 deletion mutant had defected preS1 expression, significantly decreased viral mRNA level and SP II promoter activity; while preS2 deletion mutant had defected preS2 expression, and significantly decreased viral mRNA level. CONCLUSIONS HBV preS deletion was associated with advancement of liver diseases not only presented in preS deletion incidence, but also in the deletion pattern. Patients with preS2 deletion might have a higher risk to develop HCC.
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Affiliation(s)
- Xiaodong Li
- Research Center for Clinical and Translational Medicine, Beijing 302 Hospital, Beijing 100039, China
| | - Yaqun Qin
- Research Center for Clinical and Translational Medicine, Beijing 302 Hospital, Beijing 100039, China
| | - Yan Liu
- Research Center for Clinical and Translational Medicine, Beijing 302 Hospital, Beijing 100039, China
| | - Fan Li
- The Second Liver Cirrhosis Medical Center, Beijing 302 Hospital, Beijing 100039, China
| | - Hao Liao
- Research Center for Clinical and Translational Medicine, Beijing 302 Hospital, Beijing 100039, China
| | - Shanshan Lu
- Research Center for Clinical and Translational Medicine, Beijing 302 Hospital, Beijing 100039, China
| | - Yan Qiao
- Research Center for Clinical and Translational Medicine, Beijing 302 Hospital, Beijing 100039, China
| | - Dongping Xu
- Research Center for Clinical and Translational Medicine, Beijing 302 Hospital, Beijing 100039, China.
| | - Jin Li
- Medical Department, Beijing 302 Hospital, Beijing 100039, China.
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Zhu HL, Li X, Li J, Zhang ZH. Genetic variation of occult hepatitis B virus infection. World J Gastroenterol 2016; 22:3531-3546. [PMID: 27053845 PMCID: PMC4814639 DOI: 10.3748/wjg.v22.i13.3531] [Citation(s) in RCA: 57] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/29/2015] [Revised: 12/13/2015] [Accepted: 12/30/2015] [Indexed: 02/06/2023] Open
Abstract
Occult hepatitis B virus infection (OBI), characterized as the persistence of hepatitis B virus (HBV) surface antigen (HBsAg) seronegativity and low viral load in blood or liver, is a special form of HBV infection. OBI may be related mainly to mutations in the HBV genome, although the underlying mechanism of it remains to be clarified. Mutations especially within the immunodominant “α” determinant of S protein are “hot spots” that could contribute to the occurrence of OBI via affecting antigenicity and immunogenicity of HBsAg or replication and secretion of virion. Clinical reports account for a large proportion of previous studies on OBI, while functional analyses, especially those based on full-length HBV genome, are rare.
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20
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Sarkar N, Panigrahi R, Pal A, Biswas A, Singh SP, Kar SK, Bandopadhyay M, Das D, Saha D, Kanda T, Sugiyama M, Chakrabarti S, Banerjee A, Chakravarty R. Expression of microRNA-155 correlates positively with the expression of Toll-like receptor 7 and modulates hepatitis B virus via C/EBP-β in hepatocytes. J Viral Hepat 2015; 22:817-27. [PMID: 25720442 DOI: 10.1111/jvh.12390] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/26/2014] [Accepted: 11/15/2014] [Indexed: 12/11/2022]
Abstract
Effective recognition of viral infection and successive activation of antiviral innate immune responses are vital for host antiviral defence, which largely depends on multiple regulators, including Toll-like receptors (TLRs) and microRNAs. Several early reports suggest that specific TLR-mediated immune responses can control hepatitis B virus (HBV) replication and express differentially with disease outcome. Considering the versatile function of miR-155 in the TLR-mediated innate immune response, we aimed to study the association between miR-155 and TLRs and their subsequent impact on HBV replication using both a HBV-replicating stable cell line (HepG2.2.15) and HBV-infected liver biopsy and serum samples. Our results showed that miR-155 was suppressed during HBV infection and a subsequent positive correlation of miR-155 with TLR7 activation was noted. Further, ectopic expression of miR-155 in vitro reduced HBV load as evidenced from reduced viral DNA, mRNA and subsequently reduced level of secreted viral antigens (HBsAg and HBeAg). Our results further suggested that CCAAT/enhancer-binding protein-β (C/EBP-β), a positive regulator of HBV transcription, was inhibited by miR-155. Taken together, our study established a correlation between miR-155 and TLR7 during HBV infection and also demonstrated in vitro that increased miR-155 level could help to reduce HBV viral load by targeting C/EBP-β.
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Affiliation(s)
- N Sarkar
- ICMR Virus Unit, Kolkata, ID & BG Hospital Campus, Kolkata, India
| | - R Panigrahi
- ICMR Virus Unit, Kolkata, ID & BG Hospital Campus, Kolkata, India
| | - A Pal
- ICMR Virus Unit, Kolkata, ID & BG Hospital Campus, Kolkata, India
| | - A Biswas
- ICMR Virus Unit, Kolkata, ID & BG Hospital Campus, Kolkata, India
| | - S P Singh
- Department of Gastroenterology, SCB Medical College, Cuttack, India.,Kalinga Gastroenterology Foundation, Beam Diagnostics Premises, Cuttack, India
| | - S K Kar
- Department of Gastroenterology, SCB Medical College, Cuttack, India
| | - M Bandopadhyay
- ICMR Virus Unit, Kolkata, ID & BG Hospital Campus, Kolkata, India
| | - D Das
- ICMR Virus Unit, Kolkata, ID & BG Hospital Campus, Kolkata, India
| | - D Saha
- ICMR Virus Unit, Kolkata, ID & BG Hospital Campus, Kolkata, India
| | - T Kanda
- Department of Medicine and Clinical Oncology, Chiba University, Graduate School of Medicine, Chiba, Japan
| | - M Sugiyama
- National Center for Global Health and Medicine (NCGM), Ichikawa, Japan
| | - S Chakrabarti
- ICMR Virus Unit, Kolkata, ID & BG Hospital Campus, Kolkata, India.,National Institute of Cholera and Enteric Diseases, Kolkata, India
| | - A Banerjee
- ICMR Virus Unit, Kolkata, ID & BG Hospital Campus, Kolkata, India
| | - R Chakravarty
- ICMR Virus Unit, Kolkata, ID & BG Hospital Campus, Kolkata, India
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21
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Bock CT, Düchting A, Utta F, Brunner E, Sy BT, Klingel K, Lang F, Gawaz M, Felix SB, Kandolf R. Molecular phenotypes of human parvovirus B19 in patients with myocarditis. World J Cardiol 2014; 6:183-195. [PMID: 24772258 PMCID: PMC3999338 DOI: 10.4330/wjc.v6.i4.183] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/11/2013] [Revised: 01/16/2014] [Accepted: 02/19/2014] [Indexed: 02/06/2023] Open
Abstract
AIM: To investigate molecular phenotypes of myocardial B19V-infection to determine the role of B19V in myocarditis and dilated cardiomyopathy (DCM).
METHODS: Endomyocardial biopsies (EMBs) from 498 B19V-positive patients with myocarditis and DCM were analyzed using molecular methods and functional experiments. EMBs were obtained from the University Hospitals of Greifswald and Tuebingen and additionally from 36 German cardiology centers. Control tissues were obtained at autopsy from 34 victims of accidents, crime or suicide. Identification of mononuclear cell infiltrates in EMBs was performed using immunohistological staining. Anti-B19V-IgM and anti-B19V-IgG were analyzed by enzyme-linked immunosorbent assay (ELISA). B19V viral loads were determined using in-house quantitative real-time polymerase chain reaction (PCR). For B19V-genotyping a new B19V-genotype-specific restriction fragment length polymorphism (RFLP)-PCR was established. B19V-genotyping was verified by direct DNA-sequencing and sequences were aligned using BLAST and BioEdit software. B19V P6-promoter and HHV6-U94-transactivator constructs were generated for cell culture experiments. Transfection experiments were conducted using human endothelial cells 1. Luciferase reporter assays were performed to determine B19V-replication activity. Statistical analysis and graphical representation were calculated using SPSS and Prism5 software.
RESULTS: The prevalence of B19V was significantly more likely to be associated with inflammatory cardiomyopathy (iCMP) compared to uninflamed DCM (59.6% vs 35.3%) (P < 0.0001). The detection of B19V-mRNA replication intermediates proved that replication of B19V was present. RFLP-PCR assays showed that B19V-genotype 1 (57.4%) and B19V-genotype 2 (36.7%) were the most prevalent viral genotypes. B19V-genotype 2 was observed more frequently in EMBs with iCMP (65.0%) compared to DCM (35%) (P = 0.049). Although there was no significant difference in gender-specific B19V-loads, women were more frequently infected with B19V-genotype 2 (44.6%) than men (36.0%) (P = 0.0448). Coinfection with B19V and other cardiotropic viruses was found in 19.2% of tissue samples and was associated with higher B19V viral load compared to B19V-monoinfected tissue (P = 0.0012). The most frequent coinfecting virus was human herpes virus 6 (HHV6, 16.5%). B19V-coinfection with HHV6 showed higher B19V-loads compared to B19V-monoinfected EMBs (P = 0.0033), suggesting that HHV6 had transactivated B19V. In vitro experiments confirmed a 2.4-fold increased B19V P6-promoter activity by the HHV6 U94-transactivator.
CONCLUSION: The finding of significantly increased B19V loads in patients with histologically proven cardiac inflammation suggests a crucial role of B19V-genotypes and reactivation of B19V-infection by HHV6-coinfection in B19V-associated iCMP. Our findings suggest that B19V-infection of the human heart can be a causative event for the development of an endothelial cell-mediated inflammatory disease and that this is related to both viral load and genotype.
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Abstract
MicroRNAs (miRNAs), a class of short non-coding RNAs, have been studied intensely and extensively in the past decade in every aspect of biological processes, including cell differentiation, proliferation and death. These findings pointed out the pivotal role of miRNA in posttranscriptional control of gene expression in animals and established miRNAs as therapeutic targets for different pathophysiological processes, including liver disease. Here we have discussed the recent advances made in identifying the miRNAs deregulated in different liver diseases such as obesity, hepatitis, alcoholic and nonalcoholic steatohepatitis, cirrhosis and hepatocellular carcinoma, as well as pathophysiological conditions such as developmental abnormality. We have specifically reviewed the role of miRNAs in these diseases and discussed critically potential impacts of these miRNAs as biomarkers and/or therapeutic targets in liver pathobiology in the clinical setting. Finally, we have highlighted the latest techniques or preclinical and/or clinical trials that are being developed to replenish or inhibit the deregulated miRNAs.
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Affiliation(s)
- Shu-Hao Hsu
- Department of Molecular and Cellular Biochemistry, The Ohio State University, Columbus, OH 43210, USA. Comprehensive Cancer Center, The Ohio State University, 420 West 12th Avenue, 606 TMRF Building, Columbus, OH 43210, USA
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Kao JH, Liu CJ, Jow GM, Chen PJ, Chen DS, Chen BF. Fine mapping of hepatitis B virus pre-S deletion and its association with hepatocellular carcinoma. Liver Int 2012; 32:1373-81. [PMID: 22676233 DOI: 10.1111/j.1478-3231.2012.02826.x] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/20/2012] [Accepted: 05/01/2012] [Indexed: 01/16/2023]
Abstract
BACKGROUND Naturally occurring pre-S deletion mutants have been identified in hepatitis B virus (HBV)-related hepatocellular carcinoma (HCC). AIMS This study investigated whether specific deletions within the pre-S region were associated with HCC development. METHODS The virologic characteristics of 56 HBV chronic carriers and 112 age-matched patients with HBV-related HCC were examined. RESULTS The HCC patients had a significantly higher frequency of high viral load, basal core promoter mutation and pre-S deletion than chronic carriers. Sequencing analysis showed that the deleted regions were clustered mainly in the C terminus of pre-S1 (70.5%) and the N terminus of pre-S2 (72.7%) in HCC patients. Immuno-epitope mapping of these pre-S deletion sequences showed that all the deletion regions encompassed T- and B- cell epitopes and the B-cell epitope at amino acid 1-6 of pre-S2 was significantly deleted in HCC patients (60.0% vs. 0.0%; P = 0.036). Functional mapping of these deletion mutants showed that most of HCC patients lost one or more functional sites and the deletion of site for viral secretion (aa 1-5 of pre-S2 domain) was significantly detected in HCC patients than chronic carriers (62.5% vs. 0.0%; P = 0.029). Computational protein function prediction indicated that these mutants may have different molecular functions and participate in other biological processes compared with wild-type pre-S. CONCLUSIONS Deletion of B-cell epitope at amino acid 1-6 of pre-S2 region and the site for virion secretion are significantly associated with the development of HCC in HBV carriers.
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Affiliation(s)
- Jia-Horng Kao
- Division of Gastroenterology, Department of Internal Medicine, National Taiwan University Hospital, Taipei, Taiwan
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Functional analysis of hepatitis B virus pre-s deletion variants associated with hepatocellular carcinoma. J Biomed Sci 2012; 19:17. [PMID: 22313590 PMCID: PMC3323466 DOI: 10.1186/1423-0127-19-17] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2011] [Accepted: 02/07/2012] [Indexed: 02/07/2023] Open
Abstract
BACKGROUND Naturally occurring pre-S deletion mutants have been identified in hepatitis B carriers and shown to be associated with the development of hepatocellular carcinoma. The phenotypes of these pre-S deletion genomes remain unclear, and they were investigated in this study. METHODS The pre-S deletion genomes: (1) pre-S1 deletion, (2) deletion spanning pre-S1 and pre-S2, (3) pre-S2 N-terminal deletion, and (4) pre-S2 internal deletion were constructed and analyzed by transfection into Huh-7 cells. RESULTS Functional analyses reveal that these mutants were divided into two groups: S promoter deletion and non-S promoter deletion variants. Compared with the wild-type genome, S promoter deletion variants led to an inverse ratio of pre-S1 mRNA and pre-S2/S mRNA, and intracellular accumulation of surface proteins. An interesting finding is that a small amount of L proteins was detected in the medium from S promoter deletion variant-transfected cells. Non-S promoter deletion variants conversely displayed a wild-type like mRNA and protein pattern. The secretion of surface proteins from non-S promoter deletion variants was inhibited less than from S promoter deletion variant. Immunofluorescence analysis showed mutant surface proteins colocalized with ER and exhibited an atypical distribution: granular staining pattern in the S-promoter deletion variants and perinuclear staining pattern in the non-S promoter deletion variants. CONCLUSION This study shows that these pre-S deletion genomes exhibit two different phenotypes in mRNA transcription, surface protein expression and secretion. This diversity seems to result from the deletion of S promoter rather than result from the deletion of pre-S1 or pre-S2.
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Liu WH, Yeh SH, Chen PJ. Role of microRNAs in hepatitis B virus replication and pathogenesis. BIOCHIMICA ET BIOPHYSICA ACTA-GENE REGULATORY MECHANISMS 2011; 1809:678-85. [DOI: 10.1016/j.bbagrm.2011.04.008] [Citation(s) in RCA: 68] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/05/2011] [Revised: 04/24/2011] [Accepted: 04/25/2011] [Indexed: 02/08/2023]
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Yeung P, Wong DKH, Lai CL, Fung J, Seto WK, Yuen MF. Association of hepatitis B virus pre-S deletions with the development of hepatocellular carcinoma in chronic hepatitis B. J Infect Dis 2011; 203:646-54. [PMID: 21227916 DOI: 10.1093/infdis/jiq096] [Citation(s) in RCA: 82] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
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.
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Affiliation(s)
- Pok Yeung
- Department of Medicine, The University of Hong Kong, Queen Mary Hospital, Hong Kong, Taiwan
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Abstract
Hepatitis B virus (HBV) is tightly controlled by a number of noncytotoxic mechanisms. This control occurs within the host hepatocyte at different steps of the HBV replication cycle. HBV persists by establishing a nuclear minichromosome, HBV cccDNA, serving as a transcription template for the viral pregenome and viral mRNAs. Nucleoside/nucleotide analogues widely used for antiviral therapy as well as most antiviral cytokines act at steps after transcription of HBV RNAs and thus can control virus replication but do not directly affect its gene expression. Control of HBV at the level of transcription in contrast is able to restrict both, HBV replication and gene expression. In the review, we focus on how HBV is controlled at the level of transcription. We discuss how the composition of transcription factors determines HBV gene expression and replication and how this may be influenced by antivirally active substances, e.g. the cytokine IL-6 or helioxanthin analogues, or by the differentiation state of the hepatocyte.
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Affiliation(s)
- M Quasdorff
- Department of Gastroenterology and Hepatology, University Hospital Cologne, Germany
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28
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Abstract
Hepatitis B virus (HBV) is tightly controlled by a number of noncytotoxic mechanisms. This control occurs within the host hepatocyte at different steps of the HBV replication cycle. HBV persists by establishing a nuclear minichromosome, HBV cccDNA, serving as a transcription template for the viral pregenome and viral mRNAs. Nucleoside/nucleotide analogues widely used for antiviral therapy as well as most antiviral cytokines act at steps after transcription of HBV RNAs and thus can control virus replication but do not directly affect its gene expression. Control of HBV at the level of transcription in contrast is able to restrict both, HBV replication and gene expression. In the review, we focus on how HBV is controlled at the level of transcription. We discuss how the composition of transcription factors determines HBV gene expression and replication and how this may be influenced by antivirally active substances, e.g. the cytokine IL-6 or helioxanthin analogues, or by the differentiation state of the hepatocyte.
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Affiliation(s)
- M Quasdorff
- Department of Gastroenterology and Hepatology, University Hospital Cologne, Germany
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29
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Huang HP, Hsu HY, Chen CL, Ni YH, Wang HY, Tsuei DJ, Chiang CL, Tsai YC, Chen HL, Chang MH. Pre-S2 deletions of hepatitis B virus and hepatocellular carcinoma in children. Pediatr Res 2010; 67:90-4. [PMID: 19816238 DOI: 10.1203/pdr.0b013e3181c1b0b7] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
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.
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Affiliation(s)
- Hsiang-Po Huang
- Department of Medical Research, National Taiwan University Hospital, Taipei 100, Taiwan
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30
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Mu SC, Lin YM, Jow GM, Chen BF. Occult hepatitis B virus infection in hepatitis B vaccinated children in Taiwan. J Hepatol 2009; 50:264-72. [PMID: 19070923 DOI: 10.1016/j.jhep.2008.09.017] [Citation(s) in RCA: 83] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/10/2008] [Revised: 08/31/2008] [Accepted: 09/15/2008] [Indexed: 12/18/2022]
Abstract
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.
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Affiliation(s)
- Shu-Chi Mu
- Department of Pediatrics, Shin Kong Wu Ho-Su Memorial Hospital, Taipei, Taiwan
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31
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Du J, Zhou Y, Fu QX, Gong WL, Zhao F, Peng JC, Zhan LS. Bioluminescence imaging of hepatitis B virus enhancer and promoter activities in mice. FEBS Lett 2008; 582:3552-6. [PMID: 18822287 DOI: 10.1016/j.febslet.2008.09.035] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2008] [Revised: 09/09/2008] [Accepted: 09/13/2008] [Indexed: 11/18/2022]
Abstract
By bioluminescence imaging and hydrodynamic gene transfer technology, the activities of hepatitis B virus (HBV) promoters and the effects of HBV enhancers on these promoters in mice under true physiological conditions have been assessed. Our studies reveal that either of the two HBV enhancers can stimulate HBV major promoter activity in hepa 1-6 cells (in vitro) and in mouse liver (in vivo), and the enhancer effects on the three promoters (S1, S2 and X promoter) are markedly greater in vivo than in vitro. The two HBV enhancers have no cooperative action on HBV promoters in vitro or in vivo.
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Affiliation(s)
- Juan Du
- Laboratory of Blood-borne Virus, Beijing Institute of Transfusion Medicine, Tai Ping Road 27, Beijing 100850, China
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Human parvovirus B19 NS1 protein modulates inflammatory signaling by activation of STAT3/PIAS3 in human endothelial cells. J Virol 2008; 82:7942-52. [PMID: 18550668 DOI: 10.1128/jvi.00891-08] [Citation(s) in RCA: 67] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
The pathogenic mechanism by which parvovirus B19 may induce inflammatory cardiomyopathy (iCMP) is complex but is known to involve inflammatory processes, possibly including activation of JAK/STAT signaling. The nonstructural B19 protein NS1 acts as a transactivator triggering signaling cascades that eventually lead to activation of interleukin 6 (IL-6). We examined the impact of NS1 on modulation of STAT signaling in human endothelial cells (HMEC-1). The NS1 sequences were identified from B19 DNA isolated from the myocardia of patients with fatal iCMP. B19 infection as well as NS1 overexpression in HMEC-1 cells produced a significant upregulation in the phosphorylation of both tyrosine(705) and serine(727) STAT3 (P < 0.05). The increased STAT3 phosphorylation was accompanied by dimerization, nuclear translocation, and DNA binding of pSTAT3. In contrast, NS1 expression did not result in increased STAT1 activation. Notably, the expression levels of the negative regulators of STAT activation, SOCS1 and SOCS3, were not altered by NS1. However, the level of PIAS3 was upregulated in NS1-expressing HMEC-1 cells. Analysis of the transcriptional activation of target genes revealed that NS1-induced STAT3 signaling was associated with upregulation of genes involved in immune response (e.g., the IFNAR1 and IL-2 genes) and downregulation of genes associated with viral defense (e.g., the OAS1 and TYK2 genes). Our results demonstrate that B19 NS1 modulates the STAT/PIAS pathway. The NS1-induced upregulation of STAT3/PIAS3 in the absence of STAT1 phosphorylation and the lack of SOCS1/SOCS3 activation may contribute to the mechanisms by which B19 evades the immune response and establishes persistent infection in human endothelial cells. Thus, NS1 may play a critical role in the mechanism of viral pathogenesis in B19-associated iCMP.
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He XX, Lin JS, Chang Y, Zhang YH, Li Y, Wang XY, Xu D, Cheng XM. Effects of two novel nucleoside analogues on different hepatitis B virus promoters. World J Gastroenterol 2008; 14:1836-41. [PMID: 18350620 PMCID: PMC2701512 DOI: 10.3748/wjg.14.1836] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
AIM: To explore the effects of the nucleoside analogues β-L-D4A and β-LPA on hepatitis B virus (HBV) promoters.
METHODS: Four HBV promoters were amplified by polymerase chain reaction (PCR) and subcloned into the expression vector pEGFP-1. The four recombinants controlled by HBV promoters were confirmed by restriction analysis and sequencing. Human hepatoma HepG2 cells transfected with the recombinant plasmids were treated with various concentrations of β-L-D4A and β-LPA. Then, enhanced green fluorescent protein (EGFP)-positive cells were detected by fluorescence microscopy and using a fluorescence activated cell sorter (FACS).
RESULTS: Four HBV promoters were separately obtained and successfully cloned into pEGFP-1. Expression of EGFP under the control of the surface promoter (Sp) and the X promoter (Xp) was inhibited by β-L-D4A in a dose-dependent manner, while expression of EGFP under the control of the core promoter (Cp) and Xp was inhibited by β-LPA in a dose-dependent manner.
CONCLUSION: The two novel nucleoside analogues investigated here can inhibit the activities of HBV promoters in a dose-dependent manner. These findings may explain the mechanisms of action by which these two novel compounds inhibit HBV DNA replication.
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Gao ZY, Li T, Wang J, Du JM, Li YJ, Li J, Lu FM, Zhuang H. Mutations in preS genes of genotype C hepatitis B virus in patients with chronic hepatitis B and hepatocellular carcinoma. J Gastroenterol 2007; 42:761-8. [PMID: 17876546 DOI: 10.1007/s00535-007-2085-1] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/26/2006] [Accepted: 06/06/2007] [Indexed: 02/07/2023]
Abstract
BACKGROUND Hepatitis B virus (HBV) preS mutations are frequently isolated from patients with severe forms of liver disease. Meanwhile, genotype C has been shown to cause more serious liver disease than genotype B. This study assesses the frequency of preS mutation in Chinese patients with genotype C chronic HBV infection and its relation to liver damage. METHODS Seventy-nine persistently infected patients (25 asymptomatic carriers, 28 with chronic hepatitis, and 26 with hepatocellular carcinoma) with genotype C HBV were analyzed. Levels of HBV DNA, hepatitis B e antigen (HBeAg), alanine aminotransferase, and aspartate transaminase and mutations in the preS region were determined. RESULTS The correlations of preS deletion with disease progression were distinct: preS deletion mutations were more commonly found in the hepatocellular carcinoma (HCC) group than in the chronic hepatitis B (CHB) or asymptomatic carrier (ASC) groups, with the frequencies of 38.46% (10/26) in the HCC, 7.14% (2/28) in the CHB, and 4.00% (1/25) in the ASC (P = 0.001) groups. The HBeAg-positive rate and HBV DNA levels were comparable between patients with the preS mutation and those without. CONCLUSIONS PreS deletion mutations of genotype C HBV might play a role in HBV-related hepatocarcinogenesis.
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Affiliation(s)
- Zhi Yong Gao
- Department of Microbiology, Peking University Health Science Center, 38 Xueyuan Road, 100083, Beijing, China
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35
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Enomoto M, Tamori A, Kohmoto MT, Morikawa H, Habu D, Sakaguchi H, Takeda T, Seki S, Kawada N, Shiomi S, Nishiguchi S. Mutational patterns of hepatitis B virus genome and clinical outcomes after emergence of drug-resistant variants during lamivudine therapy: Analyses of the polymerase gene and full-length sequences. J Med Virol 2007; 79:1664-70. [PMID: 17854034 DOI: 10.1002/jmv.20984] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
It remains unclear whether mutational patterns of the hepatitis B virus (HBV) genome are associated with the development of severe hepatitis after the emergence of tyrosine-methionine-aspartate-aspartate (YMDD) variants during lamivudine treatment. Thirty patients with chronic hepatitis B who had YMDD variants during lamivudine therapy and were followed up subsequently while receiving lamivudine alone for at least 6 months were examined retrospectively. The lamivudine resistant mutations in the HBV polymerase gene were detected by a line probe assay, and the full-length sequences of HBV DNA were determined in some patients. Between months 5 and 33 of therapy, mutations from methionine to isoleucine at rt204 (rtM204I) were detected in 18 patients, and mutations from methionine to valine at rt204 (rtM204V) were detected in 12. The rtM204V mutations were always accompanied by mutations from leucine to methionine at rt180 (rtL180M), while rtM204I mutations were not. Baseline characteristics, alanine aminotransferase (ALT) levels, and HBV DNA levels within 6 months after the emergence of YMDD variants did not differ significantly between patients with rtM204I alone and those with rtL180M/rtM204V. No specific mutation was identified on full-length sequence analysis in three patients with a hepatitis flare. During long term follow-up, the addition of rtL180M to rtM204I was found in four patients 7-31 months after detecting the change at rt204 and was linked to increased ALT levels. In conclusion, mutational patterns of HBV DNA at the time of emergence of YMDD variants were apparently unrelated to the clinical outcomes in Japanese patients with chronic hepatitis B during lamivudine therapy.
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Affiliation(s)
- Masaru Enomoto
- Department of Hepatology, Osaka City University Medical School, Asahimachi, Abeno-ku, Osaka, Japan
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Yokosuka O, Arai M. Molecular biology of hepatitis B virus: effect of nucleotide substitutions on the clinical features of chronic hepatitis B. Med Mol Morphol 2006; 39:113-20. [PMID: 16998621 DOI: 10.1007/s00795-006-0328-5] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2006] [Accepted: 04/24/2006] [Indexed: 12/22/2022]
Abstract
Hepatitis B virus (HBV) is a major cause of liver disease worldwide. It is covered with envelope (surface antigen) proteins with the nucleocapsid (core antigen) inside. In the nucleocapsid, there is an incomplete double-stranded DNA and a DNA polymerase. Four genes, S, C, X, and P, are encoded, and these partially overlap. Mutations have been reported in each gene and in their promoter regions, and these mutations can change the efficiency of HBV replication and the clinical course of patients. In this article, we review the relationship between the molecular biology of HBV and its clinical outcome.
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Affiliation(s)
- Osamu Yokosuka
- Department of Medicine and Clinical Oncology, K1, Graduate School of Medicine, Chiba University, 1-8-1 Inohana, Chiba, 260-8670, Japan.
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37
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Chen BF, Liu CJ, Jow GM, Chen PJ, Kao JH, Chen DS. High prevalence and mapping of pre-S deletion in hepatitis B virus carriers with progressive liver diseases. Gastroenterology 2006; 130:1153-68. [PMID: 16618410 DOI: 10.1053/j.gastro.2006.01.011] [Citation(s) in RCA: 232] [Impact Index Per Article: 12.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/01/2005] [Accepted: 12/21/2005] [Indexed: 12/17/2022]
Abstract
BACKGROUND & AIMS The interactions among pre-S deletion, precore (PC) mutation, and basal core promoter (BCP) mutation in various stages of chronic hepatitis B virus (HBV) infection remain unclear and were thus investigated in this study. METHODS The sequences of the pre-S region and the BCP (A1762T, G1764A) and PC (G1896A) mutations were determined in 46 HBV chronic carriers (CC) and 106 age-matched carriers with different stages of liver diseases, including 38 chronic hepatitis (CH), 18 cirrhosis (LC), and 50 hepatocellular carcinoma (HCC). RESULTS A higher prevalence of pre-S deletion and BCP and PC mutations was found in carriers with progressive liver diseases compared with the CC group. By logistic regression analysis, patients with pre-S deletion and BCP mutation were significantly associated with the development of progressive liver diseases than those without. Combination of mutations rather than single mutation was associated with the development of progressive liver diseases, especially in combination with pre-S deletion. Sequencing analysis showed that the deleted regions were more often in the 3' terminus of pre-S1 and the 5' terminus of pre-S2. Further mapping of these pre-S deletion sequences found that all the deletion regions encompassed T- and B-cell epitopes, and most of them lost 1 or more functional sites. CONCLUSIONS Our data indicate that patients with progressive liver diseases have a higher frequency of pre-S deletion.
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Affiliation(s)
- Bing-Fang Chen
- School of Medicine, Fu Jen Catholic University, Taipei, Taiwan
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38
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Chen BF, Liu CJ, Jow GM, Chen PJ, Kao JH, Chen DS. Evolution of Hepatitis B virus in an acute hepatitis B patient co-infected with genotypes B and C. J Gen Virol 2006; 87:39-49. [PMID: 16361416 DOI: 10.1099/vir.0.81357-0] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
The interactions between different genotypes of Hepatitis B virus (HBV) in co-infected patients remain largely unknown, especially in acute infection. Here, the evolution of HBV strains was studied in an acute, self-limited hepatitis B patient co-infected with genotypes Ba (B2) and C. Virological analyses were performed at four time points after admission: T1 (5 days), T2 (11 days), T3 (22 days) and T4 (260 days). A dominant-genotype change from genotype C to Ba was found after anti-HBV e antigen (anti-HBe) seroconversion. Further clonal and phylogenetic analyses of the pre-S and pre-core/core regions of HBV were carried out to clarify the interactions between genotypes Ba and C. All clones propagated from T1 and T2 were of genotype C. In contrast, clones propagated from T3 (after anti-HBe seroconversion) were of genotype Ba, C and/or recombinant within the pre-S region. At T4, all clones were of genotype Ba with a 123 bp (from nt 3147 of the pre-S1 region to nt 54 of the pre-S2 region) in-frame pre-S deletion and had lost the start codon of the middle envelope protein and the nucleocapsid-binding site. Phylogenetic analysis showed that genetic distance was greater at T3 after seroconversion to anti-HBe. By using SimPlot, the breakpoint of one pre-S recombinant was located at nt 3069-3100 and the other two at nt 49-87. In conclusion, HBV genotype Ba may overtake genotype C as the predominant strain after anti-HBe seroconversion in acute hepatitis B. Recombination within the pre-S region emerged transiently and the pre-S deletion mutant was finally cleared.
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Affiliation(s)
- Bing-Fang Chen
- School of Medicine, Fu Jen Catholic University, Taipei, Taiwan
| | - Chun-Jen Liu
- Division of Gastroenterology, Department of Internal Medicine, National Taiwan University Hospital, Taipei, Taiwan
| | - Guey-Mei Jow
- School of Medicine, Fu Jen Catholic University, Taipei, Taiwan
| | - Pei-Jer Chen
- Department of Medical Research, National Taiwan University Hospital, Taipei, Taiwan
- Graduate Institute of Clinical Medicine, National Taiwan University Hospital, Taipei, Taiwan
- Division of Gastroenterology, Department of Internal Medicine, National Taiwan University Hospital, Taipei, Taiwan
| | - Jia-Horng Kao
- Hepatitis Research Center, National Taiwan University Hospital, Taipei, Taiwan
- Graduate Institute of Clinical Medicine, National Taiwan University Hospital, Taipei, Taiwan
- Division of Gastroenterology, Department of Internal Medicine, National Taiwan University Hospital, Taipei, Taiwan
- Department of Medical Research, National Taiwan University Hospital, Taipei, Taiwan
| | - Ding-Shinn Chen
- Graduate Institute of Clinical Medicine, National Taiwan University Hospital, Taipei, Taiwan
- Division of Gastroenterology, Department of Internal Medicine, National Taiwan University Hospital, Taipei, Taiwan
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Huang TJ, Lu CC, Tsai JC, Yao WJ, Lu X, Lai MD, Liu HS, Shiau AL. Novel Autoregulatory Function of Hepatitis B Virus M Protein on Surface Gene Expression. J Biol Chem 2005; 280:27742-54. [PMID: 15899887 DOI: 10.1074/jbc.m502209200] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
The hepatitis B virus surface gene consists of a single open reading frame divided into three coding regions: pre-S1, pre-S2, and S. By alternate translation at each of the three initiation codons, L, M, and S proteins can be synthesized. Studies have shown that M protein is not essential for viral replication, virion morphogenesis, or in vitro infectivity. In this study, we show that native M protein can regulate surface gene expression at the transcriptional level. The regulatory effect of M protein is mediated through the CCAAT box within the S promoter. Deletion mapping analysis indicated that the transactivating effect of M protein is mediated through amino acids 1-57 of M protein (the MHBs(au) domain), although its maximal transactivation activity coincides with that of the pre-S2 domain. This conclusion is supported by the fact that disruption of the putative V8 protease site at the pre-S2/S domain junction not only rendered M protein incapable of transactivating the S promoter but also inactivated its nuclear translocation potential. Immunoprecipitation and immunoblot experiments demonstrated that pre-S2 interacts with the three subunits of the CCAAT box-binding factor/nuclear factor Y, the cognate binding protein of the CCAAT box. These results demonstrate and define a novel regulatory role of M protein, which, under natural conditions, may undergo a proteolytic process to generate an MHBs(au) species that will be translocated inside the nucleus, where it will interact with the CCAAT box-binding factor to regulate surface gene expression. Because the CCAAT box is located at a fixed position within numerous promoters, these observations might provide a plausible explanation for hepatitis B virus-associated hepatocarcinogenesis.
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Affiliation(s)
- Tsurng-Juhn Huang
- Institute of Basic Medical Sciences, Medical College, National Cheng Kung University, Tainan, Taiwan
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40
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Vietheer PTK, Netter HJ, Sozzi T, Bartholomeusz A. Failure of the lamivudine-resistant rtM204I hepatitis B virus mutants to efficiently support hepatitis delta virus secretion. J Virol 2005; 79:6570-3. [PMID: 15858045 PMCID: PMC1091693 DOI: 10.1128/jvi.79.10.6570-6573.2005] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
Hepatitis delta virus (HDV) is encapsidated by the envelope proteins of hepatitis B virus (HBV). The major HBV lamivudine (LMV)-resistant mutations in the polymerase gene within the reverse transcriptase (rt) region at rtM204V or rtM204I are associated with changes in the overlapping envelope gene products, in particular, the gene encoding small envelope protein (s) at sI195M or sW196L/S/Stop. We have demonstrated that the LMV resistance mutations corresponding to sW196L/S inhibited secretion of HDV particles, while changes corresponding to sI195M did not affect secretion. Differential efficiencies of HBsAg proteins expressed by LMV-resistant HBV to support HDV secretion may have consequences for clinical prognosis as coinfected patients are treated with antiviral agents.
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Affiliation(s)
- P T K Vietheer
- Victorian Infectious Diseases Reference Laboratory, 10 Wreckyn St., North Melbourne, Vic 3051, Australia
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41
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N/A. N/A. Shijie Huaren Xiaohua Zazhi 2004; 12:2737-2739. [DOI: 10.11569/wcjd.v12.i11.2737] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
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Affiliation(s)
- Christian Trautwein
- Department of Gastroenterology, Hepatology and Endocrinology, Medizinische Hochschule Hannover, Carl-Neuberg-Str. 1, 30625 Hannover, Germany.
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Abstract
Previous studies of human hepatitis B virus (HBV) transcription revealed the requirement of two enhancer elements. Enhancer I (EnhI) is located upstream of the X promoter and is targeted by multiple activators, including basic leucine zipper proteins, and enhancer II (EnhII) is located upstream to the PreCore promoter and is targeted mainly by nuclear receptors (NRs). The mode of interplay between these enhancers and their unique contributions in regulating HBV transcription remained obscure. By using time course analysis we revealed that the HBV transcripts are categorized into early and late groups. Chang (CCL-13) cells are impaired in expression of the late transcripts. This could be corrected by overexpressing EnhII activators, such as hepatocyte nuclear factor 4 alpha, the retinoid X receptor alpha, and the peroxisome proliferator-activated receptor alpha, suggesting that in Chang cells EnhI but not EnhII is active. Replacing the 5'-end EnhI sequence with a synthetic Gal4 response (UAS) DNA fragment ceased the production of the early transcripts. Under this condition NR overexpression poorly activated EnhII. However, activation of the UAS by Gal4-p53 restored both the expression of the early transcripts and the EnhII response to NRs. Thus, a functional EnhI is required for activation of EnhII. We found a major difference between Gal4-p53 and Gal4-VP16 behavior. Gal4-p53 activated the early transcripts, while Gal4-VP16 inhibited the early transcripts but activated the late transcripts. These findings indicate that the composition of the EnhI binding proteins may play a role in early to late switching. Our data provides strong evidence for the role of EnhI in regulating global and temporal HBV gene expression.
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Affiliation(s)
- Gilad Doitsh
- Department of Molecular Genetics, Weizmann Institute of Science, Rehovot 76100, Israel
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Sugauchi F, Ohno T, Orito E, Sakugawa H, Ichida T, Komatsu M, Kuramitsu T, Ueda R, Miyakawa Y, Mizokami M. Influence of hepatitis B virus genotypes on the development of preS deletions and advanced liver disease. J Med Virol 2003; 70:537-44. [PMID: 12794715 DOI: 10.1002/jmv.10428] [Citation(s) in RCA: 94] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Hepatitis B virus (HBV) mutants with deletions in the preS region have not been evaluated for association with viral genotypes. In a case-control study, HBV DNA samples collected from 80 each of carriers infected with HBV genotype B or C were examined for preS deletions. PreS deletion mutants were found in a total of 37 of 160 (23%) HBV carriers. Carriers with preS deletion mutants were older (56.0 +/- 12.7 vs 49.3 +/- 16.9 years, P < 0.05), were infected more frequently with HBV genotype C (84% vs 40%, P < 0.05), and had more advanced disease, such as liver cirrhosis and hepatocellular carcinoma (54% vs 31%; P < 0.05), than did those without such mutants. In a multivariate analysis, genotype C (odds ratio [OR] = 9.3, P < 0.001) and advanced liver disease (OR = 3.1, P < 0.01) were the most significant variables in association with preS deletions. A direct repeat sequence (TCAGG) was found at the start or at the end of preS1 deletions in 6 of the 20 (30%) cases examined, and preS2 deletions in these cases were clustered over the 5'-terminal half of this region. These results indicate that the development of preS deletion mutants depends on HBV genotypes and that it may be associated with progressive liver disease.
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Affiliation(s)
- Fuminaka Sugauchi
- Department of Internal Medicine and Molecular Science, Nagoya City University Graduate School of Medical Sciences, Nagoya, Japan
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N/A. N/A. Shijie Huaren Xiaohua Zazhi 2003; 11:1002-1004. [DOI: 10.11569/wcjd.v11.i7.1002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
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N/A. N/A. Shijie Huaren Xiaohua Zazhi 2003; 11:1004-1006. [DOI: 10.11569/wcjd.v11.i7.1004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
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Alhababi F, Sallam TA, Tong CYW. The significance of 'anti-HBc only' in the clinical virology laboratory. J Clin Virol 2003; 27:162-9. [PMID: 12829038 DOI: 10.1016/s1386-6532(02)00171-3] [Citation(s) in RCA: 54] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
BACKGROUND Isolated detection of hepatitis B core antibody (anti-HBc) in the absence of surface antigen (HBsAg) or antibody (anti-HBs) has been reported, particularly among individuals infected with human immunodeficiency virus (HIV) and hepatitis C virus (HCV). The significance of this phenomenon is unknown and it is unclear whether all individuals with such serological pattern need further molecular investigations. OBJECTIVES To determine the prevalence of 'anti-HBc only' in samples referred to a clinical virology laboratory and to evaluate its significance and possible mechanisms. STUDY DESIGN Samples identified as anti-HBc positive (389/4359, 8.9%) during an 11-month period were investigated for HBsAg, anti-HBs, anti-HCV and anti-HIV. 'Anti-HBc only' samples were tested for HBV DNA using a nested qualitative PCR. Viral loads were measured in samples with detectable HBV DNA and the DNA sequences were analysed. RESULTS Of 379 samples with detectable anti-HBc, 155 (40.9%) were 'anti-HBc only'. HBV DNA was detected in 6/151 (4%), all of which had a viral load <400 copies per ml. Anti-HIV was found in 50/151 (33.1%) and anti-HCV in 14/151 (9.3%). Of these, only one of the HIV infected patients had detectable HBV DNA. Phylogenetic analysis of the HBV surface gene from three patients showed a variety of genotypes (A, E and G). One sequence had a mutation in codon 144, which has previously been reported to give false negative HBsAg results. CONCLUSIONS 'Anti-HBc only' is a common phenomenon in the clinical virology laboratory but only a small proportion of samples had detectable HBV DNA. The presence of HBsAg mutants with possible false negative HBsAg test result is of concern. Samples with 'anti-HBc only' could be used to monitor the emergence of these mutants.
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Affiliation(s)
- Fadel Alhababi
- Department of Biosciences, University of Westminster, London, UK
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Chen Y, Michitaka K, Matsubara H, Yamamoto K, Horiike N, Onji M. Complete genome sequence of hepatitis B virus (HBV) from a patient with fulminant hepatitis without precore and core promoter mutations: comparison with HBV from a patient with acute hepatitis infected from the same infectious source. J Hepatol 2003; 38:84-90. [PMID: 12480564 DOI: 10.1016/s0168-8278(02)00325-2] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
BACKGROUND/AIMS There is a paucity of information regarding hepatitis B virus (HBV) from patients with fulminant hepatitis (FH) without precore (pre-C, nt 1896) and core promoter (CP, nt 1762, 1764) mutations. METHODS Pre-C and CP mutations were studied in eight patients with FH and 26 patients with acute hepatitis (AH) due to HBV. One patient with FH (FH1) was infected with HBV without these mutations. Interestingly, the sera of the infectious source (IS1) and of a patient with AH (AH1) infected from IS1 were available. Complete HBV genomes from these three patients were analyzed. RESULTS These mutations were found in seven of eight FH and five of 26 AH (P<0.01). HBV from FH1, IS1 and AH1 belonged to genotype D. Nucleotide difference between FH1 and AH1 was six of 3182 bases (nt 493, 998, 1173, 2928, 3067, and 3078). Two and five substitutions of deduced amino acid sequences were found in the pre-S1 and polymerase regions, respectively. The same nucleotide substitutions at nt 493, 1173, 2928 and 3067 were found in several patients with FH in our laboratory or GenBank. CONCLUSIONS These six nucleotide substitutions of HBV DNA could be candidates of mutations relating to FH.
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Affiliation(s)
- Yan Chen
- Third Department of Internal Medicine, Ehime University School of Medicine, Shigenobu-cho, Onsen-gun, Ehime 791-0295, Japan
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Abstract
The precise modulation of hepatitis B virus (HBV) gene expression is essential for replication of the virus. HBV sequences are transcribed under the control of the preC/pregenomic, S1, S2 and X promoters. With the exception of S1, all the HBV promoters lack the orthodox TATA box motifs required for the formation of the transcription initiation complex, and as such they represent a unique model of transcription initiation elements. The presence of two enhancer sequences and negative regulatory elements in the HBV genome further augments the controlled synthesis of HBV- RNA. All these transcription cis-elements are embedded within protein coding regions of the genome. This feature demonstrates the remarkable ability of the virus to maximize the function of its small genome. HBV transcription control elements also display a preference for liver-specific or liver-enriched trans-factors, which contributes to the liver tropism of the virus. This review outlines the major HBV transcription regulatory elements and highlights the reliance of accurate HBV gene modulation on the complex interplay between several trans-acting factors and their corresponding cis- motifs in the viral genome.
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Affiliation(s)
- Naazneen Moolla
- Hepatitis B virus Research Programme, Department of Molecular Medicine and Haematology, University of the Witwatersrand Medical School, 7 York Road, Parktown 2193, South Africa
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Jeantet D, Chemin I, Mandrand B, Zoulim F, Trepo C, Kay A. Characterization of two hepatitis B virus populations isolated from a hepatitis B surface antigen-negative patient. Hepatology 2002; 35:1215-24. [PMID: 11981772 DOI: 10.1053/jhep.2002.32710] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
In a study of surface antigen-negative, but weakly hepatitis B virus (HBV) DNA-positive, patients, we were able to amplify and clone whole HBV genomes from the serum of a cirrhotic patient. Sequencing showed that the patient harbored two different HBV populations, one of genotype A and the other of genotype D, with the genotype D genome apparently predominating. The surface antigen of the genotype A virus is heavily mutated, especially in the extracellular << determinant a >> region, with several mutations that have not been previously described. The genotype D virus is a precore mutant. Both genomes possess the common A1762T-G1764A double mutation of the basal core promoter (BCP), and the genotype D virus is also mutated in the << TATA box >> of the large surface antigen promoter. Biological characterization showed that the genotype A genome was fully replication-competent, whereas the genotype D genome replicated poorly. The small surface antigen of the genotype A virus was only very weakly recognized by commercial tests. The small surface antigen of the genotype D virus could be recognized by the tests, but it was mainly retained within transfected cells, probably because of an excess of large surface antigen. In conclusion, the cryptic nature of this double HBV infection is characterized by the predominance of the replication-deficient genotype D virus over the replication-competent genotype A virus.
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Affiliation(s)
- Damien Jeantet
- U271 INSERM, 151 cours Albert Thomas, Lyon Cedex 03, France
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