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Shen Z, Wu J, Gao Z, Zhang S, Chen J, He J, Guo Y, Deng Q, Xie Y, Liu J, Zhang J. High mobility group AT-hook 1 (HMGA1) is an important positive regulator of hepatitis B virus (HBV) that is reciprocally upregulated by HBV X protein. Nucleic Acids Res 2022; 50:2157-2171. [PMID: 35137191 PMCID: PMC8887475 DOI: 10.1093/nar/gkac070] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2021] [Revised: 01/10/2022] [Accepted: 01/25/2022] [Indexed: 11/29/2022] Open
Abstract
Chronic infection with hepatitis B virus (HBV) is associated with liver cirrhosis and hepatocellular carcinoma. Upon infection of hepatocytes, HBV covalently closed circular DNA (cccDNA) exists as histone-bound mini-chromosome, subjected to transcriptional regulation similar to chromosomal DNA. Here we identify high mobility group AT-hook 1 (HMGA1) protein as a positive regulator of HBV transcription that binds to a conserved ATTGG site within enhancer II/core promoter (EII/Cp) and recruits transcription factors FOXO3α and PGC1α. HMGA1-mediated upregulation of EII/Cp results in enhanced viral gene expression and genome replication. Notably, expression of endogenous HMGA1 was also demonstrated to be upregulated by HBV, which involves HBV X protein (HBx) interacting with SP1 transcription factor to activate HMGA1 promoter. Consistent with these in vitro results, chronic hepatitis B patients in immune tolerant phase display both higher intrahepatic HMGA1 protein levels and higher serum HBV markers compared to patients in inactive carrier phase. Finally, using a mouse model of HBV persistence, we show that targeting endogenous HMGA1 through RNA interference facilitated HBV clearance. These data establish HMGA1 as an important positive regulator of HBV that is reciprocally upregulated by HBV via HBx and also suggest the HMGA1-HBV positive feedback loop as a potential therapeutic target.
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Affiliation(s)
- Zhongliang Shen
- Department of Infectious Diseases, Shanghai Key Laboratory of Infectious Diseases and Biosafety Emergency Response, Shanghai Institute of Infectious Diseases and Biosecurity,National Medical Center for Infectious Diseases, Huashan Hospital, Fudan University, Shanghai 200040, China
- Key Laboratory of Medical Molecular Virology (Ministry of Education/National Health Commission/Chinese Academy of Medical Sciences), Department of Microbiology and Parasitology, Shanghai Institute of Infectious Diseases and Biosecurity, School of Basic Medical Sciences, Shanghai Medical College, Fudan University, Shanghai 200032, China
| | - Jingwen Wu
- Department of Infectious Diseases, Shanghai Key Laboratory of Infectious Diseases and Biosafety Emergency Response, Shanghai Institute of Infectious Diseases and Biosecurity,National Medical Center for Infectious Diseases, Huashan Hospital, Fudan University, Shanghai 200040, China
| | - Zixiang Gao
- Key Laboratory of Medical Molecular Virology (Ministry of Education/National Health Commission/Chinese Academy of Medical Sciences), Department of Microbiology and Parasitology, Shanghai Institute of Infectious Diseases and Biosecurity, School of Basic Medical Sciences, Shanghai Medical College, Fudan University, Shanghai 200032, China
| | - Shenyan Zhang
- Department of Infectious Diseases, Shanghai Key Laboratory of Infectious Diseases and Biosafety Emergency Response, Shanghai Institute of Infectious Diseases and Biosecurity,National Medical Center for Infectious Diseases, Huashan Hospital, Fudan University, Shanghai 200040, China
| | - Jingwen Chen
- Department of Infectious Diseases, Shanghai Key Laboratory of Infectious Diseases and Biosafety Emergency Response, Shanghai Institute of Infectious Diseases and Biosecurity,National Medical Center for Infectious Diseases, Huashan Hospital, Fudan University, Shanghai 200040, China
| | - Jingjing He
- Department of Infectious Diseases, Shanghai Key Laboratory of Infectious Diseases and Biosafety Emergency Response, Shanghai Institute of Infectious Diseases and Biosecurity,National Medical Center for Infectious Diseases, Huashan Hospital, Fudan University, Shanghai 200040, China
| | - Yifei Guo
- Department of Infectious Diseases, Shanghai Key Laboratory of Infectious Diseases and Biosafety Emergency Response, Shanghai Institute of Infectious Diseases and Biosecurity,National Medical Center for Infectious Diseases, Huashan Hospital, Fudan University, Shanghai 200040, China
| | - Qiang Deng
- Key Laboratory of Medical Molecular Virology (Ministry of Education/National Health Commission/Chinese Academy of Medical Sciences), Department of Microbiology and Parasitology, Shanghai Institute of Infectious Diseases and Biosecurity, School of Basic Medical Sciences, Shanghai Medical College, Fudan University, Shanghai 200032, China
| | - Youhua Xie
- Key Laboratory of Medical Molecular Virology (Ministry of Education/National Health Commission/Chinese Academy of Medical Sciences), Department of Microbiology and Parasitology, Shanghai Institute of Infectious Diseases and Biosecurity, School of Basic Medical Sciences, Shanghai Medical College, Fudan University, Shanghai 200032, China
- Children's Hospital of Fudan University, Shanghai 201102, China
| | - Jing Liu
- Key Laboratory of Medical Molecular Virology (Ministry of Education/National Health Commission/Chinese Academy of Medical Sciences), Department of Microbiology and Parasitology, Shanghai Institute of Infectious Diseases and Biosecurity, School of Basic Medical Sciences, Shanghai Medical College, Fudan University, Shanghai 200032, China
- Shanghai Key Laboratory of Medical Epigenetics, Institutes of Biomedical Sciences, School of Basic Medical Sciences, Shanghai Medical College, Fudan University, Shanghai 200032, China
| | - Jiming Zhang
- Department of Infectious Diseases, Shanghai Key Laboratory of Infectious Diseases and Biosafety Emergency Response, Shanghai Institute of Infectious Diseases and Biosecurity,National Medical Center for Infectious Diseases, Huashan Hospital, Fudan University, Shanghai 200040, China
- Key Laboratory of Medical Molecular Virology (Ministry of Education/National Health Commission/Chinese Academy of Medical Sciences), Department of Microbiology and Parasitology, Shanghai Institute of Infectious Diseases and Biosecurity, School of Basic Medical Sciences, Shanghai Medical College, Fudan University, Shanghai 200032, China
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52
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Dias JD, Sarica N, Cournac A, Koszul R, Neuveut C. Crosstalk between Hepatitis B Virus and the 3D Genome Structure. Viruses 2022; 14:445. [PMID: 35216038 PMCID: PMC8877387 DOI: 10.3390/v14020445] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2022] [Revised: 02/04/2022] [Accepted: 02/14/2022] [Indexed: 12/17/2022] Open
Abstract
Viruses that transcribe their DNA within the nucleus have to adapt to the existing cellular mechanisms that govern transcriptional regulation. Recent technological breakthroughs have highlighted the highly hierarchical organization of the cellular genome and its role in the regulation of gene expression. This review provides an updated overview on the current knowledge on how the hepatitis B virus interacts with the cellular 3D genome and its consequences on viral and cellular gene expression. We also briefly discuss the strategies developed by other DNA viruses to co-opt and sometimes subvert cellular genome spatial organization.
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Affiliation(s)
- João Diogo Dias
- Laboratoire de Virologie Moléculaire, Institut de Génétique Humaine, CNRS, Université de Montpellier, 34000 Montpellier, France; (J.D.D.); (N.S.)
| | - Nazim Sarica
- Laboratoire de Virologie Moléculaire, Institut de Génétique Humaine, CNRS, Université de Montpellier, 34000 Montpellier, France; (J.D.D.); (N.S.)
| | - Axel Cournac
- Unité Régulation Spatiale des Génomes, CNRS, UMR 3525, Institut Pasteur, Université de Paris, 75015 Paris, France; (A.C.); (R.K.)
| | - Romain Koszul
- Unité Régulation Spatiale des Génomes, CNRS, UMR 3525, Institut Pasteur, Université de Paris, 75015 Paris, France; (A.C.); (R.K.)
| | - Christine Neuveut
- Laboratoire de Virologie Moléculaire, Institut de Génétique Humaine, CNRS, Université de Montpellier, 34000 Montpellier, France; (J.D.D.); (N.S.)
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53
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Chang Y, Jeong SW, Jang JY. Hepatitis B Virus Reactivation Associated With Therapeutic Interventions. Front Med (Lausanne) 2022; 8:770124. [PMID: 35096867 PMCID: PMC8795508 DOI: 10.3389/fmed.2021.770124] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2021] [Accepted: 12/20/2021] [Indexed: 12/14/2022] Open
Abstract
Hepatitis B virus (HBV) reactivation associated with various therapeutic interventions is an important cause of morbidity and mortality in patients with current or resolved HBV infection. Because no curative treatment for HBV infection is yet available, there are many individuals at risk for HBV reactivation in the general population. Populations at risk for HBV reactivation include patients who are currently infected with HBV or who have been exposed to HBV in the past. HBV reactivation and its potential consequences is a concern when these populations are exposed to anti-cancer chemotherapy, immunosuppressive or immunomodulatory therapies for the management of various malignancies, rheumatologic diseases, inflammatory bowel disease, or solid-organ or hematologic stem cell transplantation. Accordingly, it has become important to understand the basics of HBV reactivation and the mechanisms by which certain therapies are more susceptible to HBV reactivation. This review aims to raise the awareness of HBV reactivation and to understand the mechanisms and the risks of HBV reactivation in various clinical settings.
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Affiliation(s)
- Young Chang
- Department of Internal Medicine, Institute for Digestive Research, Digestive Disease Center, Soonchunhyang University College of Medicine, Seoul, South Korea
| | - Soung Won Jeong
- Department of Internal Medicine, Institute for Digestive Research, Digestive Disease Center, Soonchunhyang University College of Medicine, Seoul, South Korea
| | - Jae Young Jang
- Department of Internal Medicine, Institute for Digestive Research, Digestive Disease Center, Soonchunhyang University College of Medicine, Seoul, South Korea
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54
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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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55
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Qin YP, Yu HB, Yuan SY, Yang Z, Ren F, Wang Q, Li F, Ren JH, Cheng ST, Zhou YJ, He X, Zhou HZ, Zhang Y, Tan M, Yang ML, Zhang DP, Wen X, Dong ML, Zhang H, Liu J, Li ZH, Chen Y, Huang AL, Chen WX, Chen J. KAT2A Promotes Hepatitis B Virus Transcription and Replication Through Epigenetic Regulation of cccDNA Minichromosome. Front Microbiol 2022; 12:795388. [PMID: 35140694 PMCID: PMC8818952 DOI: 10.3389/fmicb.2021.795388] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2021] [Accepted: 12/13/2021] [Indexed: 01/05/2023] Open
Abstract
Hepatitis B virus (HBV) infection remains a major health problem worldwide. Sufficient maintenance of the HBV covalently closed circular DNA (cccDNA), which serves as a template for HBV transcription, is responsible for the failure of antiviral therapies. While accumulating evidence suggests that cccDNA transcription is regulated by epigenetic machinery, particularly the acetylation and methylation of cccDNA-bound histone 3 (H3) and histone 4 (H4), the potential contributions of histone succinylation and related host factors remain obscured. Here, by screening a series of succinyltransferases and desuccinylases, we identified KAT2A as an important host factor of HBV transcription and replication. By using HBV-infected cells and mouse models with HBV infection, KAT2A was found to affect the transcriptional activity of cccDNA but did not affect cccDNA production. Mechanism studies showed that KAT2A is mainly located in the nucleus and could bind to cccDNA through interaction with HBV core protein (HBc). Moreover, we confirmed histone H3K79 succinylation (H3K79succ) as a histone modification on cccDNA minichromosome by using the cccDNA ChIP-Seq approach. Importantly, KAT2A silencing specifically reduced the level of cccDNA-bound succinylated H3K79. In conclusion, KAT2A promotes HBV transcription and replication through epigenetic machinery, and our findings may provide new insight into the treatment of HBV infection.
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Affiliation(s)
- Yi-Ping Qin
- 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
| | - Si-Yu Yuan
- 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
| | - Fang Ren
- The Key Laboratory of Molecular Biology of Infectious Diseases Designated by the Chinese Ministry of Education, Chongqing Medical University, Chongqing, China
| | - Qing Wang
- The Key Laboratory of Molecular Biology of Infectious Diseases Designated by the Chinese Ministry of Education, Chongqing Medical University, Chongqing, China
| | - Fan Li
- Department of Endocrine and Breast Surgery, The First Affiliated Hospital of 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
| | - 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
| | - Hong-Zhong Zhou
- The Key Laboratory of Molecular Biology of Infectious Diseases Designated by the Chinese Ministry of Education, Chongqing Medical University, Chongqing, China
| | - Yuan Zhang
- 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
| | - Min-Li Yang
- The Key Laboratory of Molecular Biology of Infectious Diseases Designated by the Chinese Ministry of Education, Chongqing Medical University, Chongqing, China
| | - Da-Peng Zhang
- The Key Laboratory of Molecular Biology of Infectious Diseases Designated by the Chinese Ministry of Education, Chongqing Medical University, Chongqing, China
| | - Xu Wen
- The Key Laboratory of Molecular Biology of Infectious Diseases Designated by the Chinese Ministry of Education, Chongqing Medical University, Chongqing, China
| | - Mei-Ling Dong
- The Key Laboratory of Molecular Biology of Infectious Diseases Designated by the Chinese Ministry of Education, Chongqing Medical University, Chongqing, China
| | - Hui Zhang
- The Key Laboratory of Molecular Biology of Infectious Diseases Designated by the Chinese Ministry of Education, Chongqing Medical University, Chongqing, China
| | - Jing Liu
- The Key Laboratory of Molecular Biology of Infectious Diseases Designated by the Chinese Ministry of Education, Chongqing Medical University, Chongqing, China
| | - Zhi-Hong Li
- The Key Laboratory of Molecular Biology of Infectious Diseases Designated by the Chinese Ministry of Education, Chongqing Medical University, Chongqing, China
| | - Yao Chen
- Department of Medical Examination Centre, The Second Affiliated Hospital of Chongqing Medical University, Chongqing, China
| | - Ai-Long Huang
- The Key Laboratory of Molecular Biology of Infectious Diseases Designated by the Chinese Ministry of Education, Chongqing Medical University, Chongqing, China
| | - Wei-Xian Chen
- Department of Clinical Laboratory, The Second Affiliated Hospital of Chongqing Medical University, Chongqing, China
| | - Juan Chen
- The Key Laboratory of Molecular Biology of Infectious Diseases Designated by the Chinese Ministry of Education, Chongqing Medical University, Chongqing, China
- *Correspondence: Juan Chen,
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56
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Saeed U, Piracha ZZ, Kwon H, Kim J, Kalsoom F, Chwae YJ, Park S, Shin HJ, Lee HW, Lim JH, Kim K. The HBV Core Protein and Core Particle Both Bind to the PPiase Par14 and Par17 to Enhance Their Stabilities and HBV Replication. Front Microbiol 2022; 12:795047. [PMID: 34970249 PMCID: PMC8713550 DOI: 10.3389/fmicb.2021.795047] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2021] [Accepted: 11/17/2021] [Indexed: 12/14/2022] Open
Abstract
We recently reported that the PPIase Par14 and Par17 encoded by PIN4 upregulate HBV replication in an HBx-dependent manner by binding to conserved arginine–proline (RP) motifs of HBx. HBV core protein (HBc) has a conserved 133RP134 motif; therefore, we investigated whether Par14/Par17 bind to HBc and/or core particles. Native agarose gel electrophoresis (NAGE) and immunoblotting and co-immunoprecipitation were used. Chromatin immunoprecipitation from HBV-infected HepG2-hNTCP-C9 cells was performed. NAGE and immunoblotting revealed that Par14/Par17 bound to core particles and co-immunoprecipitation revealed that Par14/Par17 interacted with core particle assembly-defective, and dimer-positive HBc-Y132A. Thus, core particles and HBc interact with Par14/Par17. Par14/Par17 interacted with the HBc 133RP134 motif possibly via substrate-binding E46/D74 and E71/D99 motifs. Although Par14/Par17 dissociated from core particles upon heat treatment, they were detected in 0.2 N NaOH-treated opened-up core particles, demonstrating that Par14/Par17 bind outside and inside core particles. Furthermore, these interactions enhanced the stabilities of HBc and core particles. Like HBc-Y132A, HBc-R133D and HBc-R133E were core particle assembly-defective and dimer-positive, demonstrating that a negatively charged residue at position 133 cannot be tolerated for particle assembly. Although positively charged R133 is solely important for Par14/17 interactions, the 133RP134 motif is important for efficient HBV replication. Chromatin immunoprecipitation from HBV-infected cells revealed that the S19 and E46/D74 residues of Par14 and S44 and E71/D99 residues of Par17 were involved in recruitment of 133RP134 motif-containing HBc into cccDNA. Our results demonstrate that interactions of HBc, Par14/Par17, and cccDNA in the nucleus and core particle–Par14/Par17 interactions in the cytoplasm are important for HBV replication.
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Affiliation(s)
- Umar Saeed
- Department of Microbiology, Ajou University School of Medicine, Suwon, South Korea.,Department of Biomedical Science, Graduate School of Ajou University, Suwon, South Korea
| | - Zahra Zahid Piracha
- Department of Microbiology, Ajou University School of Medicine, Suwon, South Korea.,Department of Biomedical Science, Graduate School of Ajou University, Suwon, South Korea
| | - Hyeonjoong Kwon
- Department of Microbiology, Ajou University School of Medicine, Suwon, South Korea.,Department of Biomedical Science, Graduate School of Ajou University, Suwon, South Korea
| | - Jumi Kim
- Department of Microbiology, Ajou University School of Medicine, Suwon, South Korea.,Department of Biomedical Science, Graduate School of Ajou University, Suwon, South Korea
| | - Fadia Kalsoom
- Department of Microbiology, Ajou University School of Medicine, Suwon, South Korea.,Department of Biomedical Science, Graduate School of Ajou University, Suwon, South Korea
| | - Yong-Joon Chwae
- Department of Microbiology, Ajou University School of Medicine, Suwon, South Korea.,Department of Biomedical Science, Graduate School of Ajou University, Suwon, South Korea
| | - Sun Park
- Department of Microbiology, Ajou University School of Medicine, Suwon, South Korea.,Department of Biomedical Science, Graduate School of Ajou University, Suwon, South Korea
| | - Ho-Joon Shin
- Department of Microbiology, Ajou University School of Medicine, Suwon, South Korea.,Department of Biomedical Science, Graduate School of Ajou University, Suwon, South Korea
| | - Hyun Woong Lee
- Department of Internal Medicine, Gangnam Severance Hospital, Yonsei University College of Medicine, Seoul, South Korea
| | - Jin Hong Lim
- Department of General Surgery, Gangnam Severance Hospital, Yonsei University College of Medicine, Seoul, South Korea
| | - Kyongmin Kim
- Department of Microbiology, Ajou University School of Medicine, Suwon, South Korea.,Department of Biomedical Science, Graduate School of Ajou University, Suwon, South Korea
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57
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Patel N, Clark S, Weiß EU, Mata CP, Bohon J, Farquhar ER, Maskell DP, Ranson NA, Twarock R, Stockley PG. In vitro functional analysis of gRNA sites regulating assembly of hepatitis B virus. Commun Biol 2021; 4:1407. [PMID: 34916604 PMCID: PMC8677749 DOI: 10.1038/s42003-021-02897-2] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2020] [Accepted: 11/16/2021] [Indexed: 11/16/2022] Open
Abstract
The roles of RNA sequence/structure motifs, Packaging Signals (PSs), for regulating assembly of an HBV genome transcript have been investigated in an efficient in vitro assay containing only core protein (Cp) and RNA. Variants of three conserved PSs, within the genome of a strain not used previously, preventing correct presentation of a Cp-recognition loop motif are differentially deleterious for assembly of nucleocapsid-like particles (NCPs). Cryo-electron microscopy reconstruction of the T = 4 NCPs formed with the wild-type gRNA transcript, reveal that the interior of the Cp shell is in contact with lower resolution density, potentially encompassing the arginine-rich protein domains and gRNA. Symmetry relaxation followed by asymmetric reconstruction reveal that such contacts are made at every symmetry axis. We infer from their regulation of assembly that some of these contacts would involve gRNA PSs, and confirmed this by X-ray RNA footprinting. Mutation of the ε stem-loop in the gRNA, where polymerase binds in vivo, produces a poor RNA assembly substrate with Cp alone, largely due to alterations in its conformation. The results show that RNA PSs regulate assembly of HBV genomic transcripts in vitro, and therefore may play similar roles in vivo, in concert with other molecular factors.
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Affiliation(s)
- Nikesh Patel
- Astbury Centre for Structural Molecular Biology, University of Leeds, Leeds, LS2 9JT, UK.
| | - Sam Clark
- Departments of Biology and Mathematics & York Centre for Complex Systems Analysis, University of York, York, YO10 5DD, UK
| | - Eva U Weiß
- Departments of Biology and Mathematics & York Centre for Complex Systems Analysis, University of York, York, YO10 5DD, UK
- Institute of Molecular Infection Biology (IMIB), University of Würzburg, Josef-Schneider-Str. 2/D15, D-97080, Würzburg, Germany
| | - Carlos P Mata
- Astbury Centre for Structural Molecular Biology, University of Leeds, Leeds, LS2 9JT, UK
- Electron and Confocal Microscopy Unit (UCCTs), National Centre for Microbiology (ISCIII). Majadahonda, Madrid, Spain
| | - Jen Bohon
- CWRU Center for Synchrotron Biosciences, NSLS-II, Brookhaven National Laboratory, Upton, NY, 11973, USA
- Los Alamos National Laboratory, Los Alamos, NM, 87545, USA
| | - Erik R Farquhar
- CWRU Center for Synchrotron Biosciences, NSLS-II, Brookhaven National Laboratory, Upton, NY, 11973, USA
| | - Daniel P Maskell
- Astbury Centre for Structural Molecular Biology, University of Leeds, Leeds, LS2 9JT, UK
| | - Neil A Ranson
- Astbury Centre for Structural Molecular Biology, University of Leeds, Leeds, LS2 9JT, UK
| | - Reidun Twarock
- Departments of Biology and Mathematics & York Centre for Complex Systems Analysis, University of York, York, YO10 5DD, UK
| | - Peter G Stockley
- Astbury Centre for Structural Molecular Biology, University of Leeds, Leeds, LS2 9JT, UK.
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58
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Kim H, Ko C, Lee JY, Kim M. Current Progress in the Development of Hepatitis B Virus Capsid Assembly Modulators: Chemical Structure, Mode-of-Action and Efficacy. Molecules 2021; 26:molecules26247420. [PMID: 34946502 PMCID: PMC8705634 DOI: 10.3390/molecules26247420] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2021] [Revised: 11/24/2021] [Accepted: 12/02/2021] [Indexed: 12/15/2022] Open
Abstract
Hepatitis B virus (HBV) is a major causative agent of human hepatitis. Its viral genome comprises partially double-stranded DNA, which is complexed with viral polymerase within an icosahedral capsid consisting of a dimeric core protein. Here, we describe the effects of capsid assembly modulators (CAMs) on the geometric or kinetic disruption of capsid construction and the virus life cycle. We highlight classical, early-generation CAMs such as heteroaryldihydropyrimidines, phenylpropenamides or sulfamoylbenzamides, and focus on the chemical structure and antiviral efficacy of recently identified non-classical CAMs, which consist of carboxamides, aryl ureas, bithiazoles, hydrazones, benzylpyridazinones, pyrimidines, quinolines, dyes, and antimicrobial compounds. We summarize the therapeutic efficacy of four representative classical compounds with data from clinical phase 1 studies in chronic HBV patients. Most of these compounds are in phase 2 trials, either as monotherapy or in combination with approved nucleos(t)ides drugs or other immunostimulatory molecules. As followers of the early CAMs, the therapeutic efficacy of several non-classical CAMs has been evaluated in humanized mouse models of HBV infection. It is expected that these next-generation HBV CAMs will be promising candidates for a series of extended human clinical trials.
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Affiliation(s)
- Hyejin Kim
- Correspondence: (H.K.); (M.K.); Tel.: +82-42-860-7130 (H.K.); +82-42-860-7540 (M.K.)
| | | | | | - Meehyein Kim
- Correspondence: (H.K.); (M.K.); Tel.: +82-42-860-7130 (H.K.); +82-42-860-7540 (M.K.)
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59
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Canonical and Divergent N-Terminal HBx Isoform Proteins Unveiled: Characteristics and Roles during HBV Replication. Biomedicines 2021; 9:biomedicines9111701. [PMID: 34829930 PMCID: PMC8616016 DOI: 10.3390/biomedicines9111701] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2021] [Revised: 11/11/2021] [Accepted: 11/11/2021] [Indexed: 11/16/2022] Open
Abstract
Hepatitis B virus (HBV) X protein (HBx) is a viral regulatory and multifunctional protein. It is well-known that the canonical HBx reading frame bears two phylogenetically conserved internal in-frame translational initiation codons at Met2 and Met3, thus possibly generating divergent N-terminal smaller isoforms during translation. Here, we demonstrate that the three distinct HBx isoforms are generated from the ectopically expressed HBV HBx gene, named XF (full-length), XM (medium-length), and XS (short-length); they display different subcellular localizations when expressed individually in cultured hepatoma cells. Particularly, the smallest HBx isoform, XS, displayed a predominantly cytoplasmic localization. To study HBx proteins during viral replication, we performed site-directed mutagenesis to target the individual or combinatorial expression of the HBx isoforms within the HBV viral backbone (full viral genome). Our results indicate that of all HBx isoforms, only the smallest HBx isoform, XS, can restore WT levels of HBV replication, and bind to the viral mini chromosome, thereby establishing an active chromatin state, highlighting its crucial activities during HBV replication. Intriguingly, we found that sequences of HBV HBx genotype H are devoid of the conserved Met3 position, and therefore HBV genotype H infection is naturally silent for the expression of the HBx XS isoform. Finally, we found that the HBx XM (medium-length) isoform shares significant sequence similarity with the N-terminus domain of the COMMD8 protein, a member of the copper metabolism MURR1 domain-containing (COMMD) protein family. This novel finding might facilitate studies on the phylogenetic origin of the HBV X protein. The identification and functional characterization of its isoforms will shift the paradigm by changing the concept of HBx from being a unique, canonical, and multifunctional protein toward the occurrence of different HBx isoforms, carrying out different overlapping functions at different subcellular localizations during HBV genome replication. Significantly, our current work unveils new crucial HBV targets to study for potential antiviral research, and human virus pathogenesis.
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In Vivo Bioluminescence Imaging of HBV Replicating Hepatocytes Allows for the Monitoring of Anti-Viral Immunity. Viruses 2021; 13:v13112273. [PMID: 34835079 PMCID: PMC8619421 DOI: 10.3390/v13112273] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2021] [Revised: 11/03/2021] [Accepted: 11/11/2021] [Indexed: 11/24/2022] Open
Abstract
Immunity against hepatitis B virus (HBV) infection is complex and not entirely understood so far, including the decisive factors leading to the development of chronic hepatitis B. This lack of a mechanistic understanding of HBV-specific immunity is also caused by a limited number of suitable animal models. Here, we describe the generation of a recombinant adenovirus expressing an HBV 1.3-overlength genome linked to luciferase (Ad-HBV-Luc) allowing for precise analysis of the quantity of infected hepatocytes. This enables sensitive and close-meshed monitoring of HBV-specific CD8 T cells and the onset of anti-viral immunity in mice. A high dose of Ad-HBV-Luc developed into chronic hepatitis B accompanied by dysfunctional CD8 T cells characterized by high expression of PD1 and TOX and low expression of KLRG1 and GzmB. In contrast, a low dose of Ad-HBV-Luc infection resulted in acute hepatitis with CD8 T cell-mediated elimination of HBV-replicating hepatocytes associated with elevated sALT levels and increased numbers of cytotoxic HBV-specific CD8 T cells. Thus, the infectious dose was a critical factor to induce either acute self-limited or chronic HBV infection in mice. Taken together, the new Ad-HBV-Luc vector will allow for highly sensitive and time-resolved analysis of HBV-specific immune responses during acute and chronic infection.
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61
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Niklasch M, Zimmermann P, Nassal M. The Hepatitis B Virus Nucleocapsid-Dynamic Compartment for Infectious Virus Production and New Antiviral Target. Biomedicines 2021; 9:1577. [PMID: 34829806 PMCID: PMC8615760 DOI: 10.3390/biomedicines9111577] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2021] [Revised: 10/19/2021] [Accepted: 10/21/2021] [Indexed: 12/11/2022] Open
Abstract
Hepatitis B virus (HBV) is a small enveloped DNA virus which replicates its tiny 3.2 kb genome by reverse transcription inside an icosahedral nucleocapsid, formed by a single ~180 amino acid capsid, or core, protein (Cp). HBV causes chronic hepatitis B (CHB), a severe liver disease responsible for nearly a million deaths each year. Most of HBV's only seven primary gene products are multifunctional. Though less obvious than for the multi-domain polymerase, P protein, this is equally crucial for Cp with its multiple roles in the viral life-cycle. Cp provides a stable genome container during extracellular phases, allows for directed intracellular genome transport and timely release from the capsid, and subsequent assembly of new nucleocapsids around P protein and the pregenomic (pg) RNA, forming a distinct compartment for reverse transcription. These opposing features are enabled by dynamic post-transcriptional modifications of Cp which result in dynamic structural alterations. Their perturbation by capsid assembly modulators (CAMs) is a promising new antiviral concept. CAMs inappropriately accelerate assembly and/or distort the capsid shell. We summarize the functional, biochemical, and structural dynamics of Cp, and discuss the therapeutic potential of CAMs based on clinical data. Presently, CAMs appear as a valuable addition but not a substitute for existing therapies. However, as part of rational combination therapies CAMs may bring the ambitious goal of a cure for CHB closer to reality.
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Affiliation(s)
| | | | - Michael Nassal
- Internal Medicine II/Molecular Biology, University Hospital Freiburg, Hugstetter Str. 55, D-79106 Freiburg, Germany; (M.N.); (P.Z.)
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62
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Liu T, Li W, Zhang Y, Siyin ST, Zhang Q, Song M, Zhang K, Liu S, Shi H. Associations between hepatitis B virus infection and risk of colorectal Cancer: a population-based prospective study. BMC Cancer 2021; 21:1119. [PMID: 34663268 PMCID: PMC8524927 DOI: 10.1186/s12885-021-08846-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2021] [Accepted: 10/07/2021] [Indexed: 11/18/2022] Open
Abstract
Background Previous studies have observed a close association between hepatitis B virus (HBV) infection and hepatocellular carcinoma (HCC) as well as extrahepatic cancers. However, research concerning the effect of HBV infection on the risk of colorectal cancer (CRC) is rare and inconsistent. This study aims to determine the relationship between HBV infection and new-onset CRC. Methods We prospectively examined the relationship between HBV infection and new-onset CRC among 93,390 participants from Kailuan Cohort study. Cox proportional hazards regression models, subgroup analyses and competing risk analyses were used to evaluate the association between HBV infection and the risk of new-onset CRC. Results During a median follow-up of 11.28 years, 448 incident CRC cases were identified. The adjusted HR (95%confidence interval (CI)) for the association of HBsAg Seropositive with CRC was 1.85(1.15 ~ 2.96) in the Cox regression. Subgroup analyses showed that the HBsAg seropositive group was associated with increased risk of new-onset CRC among male, middle-aged, normal weight, smokers and non-drinker participants, respectively. A positive association of HBV infection with the risk of CRC was observed in the adjusted sub-distribution proportional hazards (SD) models (HRSD = 1.77, 95% CI:1.11–2.84) and cause-specific hazards (CS) models (HRCS = 1.79, 95% CI: 1.13–2.91). Conclusions Our results have found a significant association between HBV infection and the risk of incident CRC among Chinese participants. Trial registration Kailuan study, ChiCTR–TNRC–11001489. Registered 24 August 2011 - Retrospectively registered, http:// http://www.chictr.org.cn/showprojen.aspx?proj=8050
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Affiliation(s)
- Tong Liu
- Department of Gastrointestinal Surgery/Clinical Nutrition, Capital Medical University Affiliated Beijing Shijitan Hospital, Beijing, 100038, China.,Beijing International Science and Technology Cooperation Base for Cancer Metabolism and Nutrition, Beijing, 100038, China.,Key Laboratory of Cancer FSMP for State Market Regulation, Beijing, 100038, China
| | - Wenqiang Li
- Department of General Surgery, Aerospace Center Hospital, Beijing, China
| | - Youcheng Zhang
- Department of Hepatobiliary Surgery, The People's Hospital of Liaoning Province, Shenyang, China.,Department of graduate school, Dalian Medical University, Dalian, China
| | - Sarah Tan Siyin
- Department of General Surgery, Beijing Children's Hospital, National Center for Children's Health, Beijing, China
| | - Qi Zhang
- Department of Gastrointestinal Surgery/Clinical Nutrition, Capital Medical University Affiliated Beijing Shijitan Hospital, Beijing, 100038, China.,Beijing International Science and Technology Cooperation Base for Cancer Metabolism and Nutrition, Beijing, 100038, China.,Key Laboratory of Cancer FSMP for State Market Regulation, Beijing, 100038, China
| | - Mengmeng Song
- Department of Gastrointestinal Surgery/Clinical Nutrition, Capital Medical University Affiliated Beijing Shijitan Hospital, Beijing, 100038, China.,Beijing International Science and Technology Cooperation Base for Cancer Metabolism and Nutrition, Beijing, 100038, China.,Key Laboratory of Cancer FSMP for State Market Regulation, Beijing, 100038, China
| | - Kangping Zhang
- Department of Gastrointestinal Surgery/Clinical Nutrition, Capital Medical University Affiliated Beijing Shijitan Hospital, Beijing, 100038, China.,Beijing International Science and Technology Cooperation Base for Cancer Metabolism and Nutrition, Beijing, 100038, China.,Key Laboratory of Cancer FSMP for State Market Regulation, Beijing, 100038, China
| | - Siqing Liu
- Department of Hepatological Surgery, Kailuan General Hospital, Tangshan, China.
| | - Hanping Shi
- Department of Gastrointestinal Surgery/Clinical Nutrition, Capital Medical University Affiliated Beijing Shijitan Hospital, Beijing, 100038, China. .,Beijing International Science and Technology Cooperation Base for Cancer Metabolism and Nutrition, Beijing, 100038, China. .,Key Laboratory of Cancer FSMP for State Market Regulation, Beijing, 100038, China.
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63
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Van Damme E, Vanhove J, Severyn B, Verschueren L, Pauwels F. The Hepatitis B Virus Interactome: A Comprehensive Overview. Front Microbiol 2021; 12:724877. [PMID: 34603251 PMCID: PMC8482013 DOI: 10.3389/fmicb.2021.724877] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2021] [Accepted: 08/17/2021] [Indexed: 12/19/2022] Open
Abstract
Despite the availability of a prophylactic vaccine, chronic hepatitis B (CHB) caused by the hepatitis B virus (HBV) is a major health problem affecting an estimated 292 million people globally. Current therapeutic goals are to achieve functional cure characterized by HBsAg seroclearance and the absence of HBV-DNA after treatment cessation. However, at present, functional cure is thought to be complicated due to the presence of covalently closed circular DNA (cccDNA) and integrated HBV-DNA. Even if the episomal cccDNA is silenced or eliminated, it remains unclear how important the high level of HBsAg that is expressed from integrated HBV DNA is for the pathology. To identify therapies that could bring about high rates of functional cure, in-depth knowledge of the virus' biology is imperative to pinpoint mechanisms for novel therapeutic targets. The viral proteins and the episomal cccDNA are considered integral for the control and maintenance of the HBV life cycle and through direct interaction with the host proteome they help create the most optimal environment for the virus whilst avoiding immune detection. New HBV-host protein interactions are continuously being identified. Unfortunately, a compendium of the most recent information is lacking and an interactome is unavailable. This article provides a comprehensive review of the virus-host relationship from viral entry to release, as well as an interactome of cccDNA, HBc, and HBx.
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Affiliation(s)
- Ellen Van Damme
- Janssen Research & Development, Janssen Pharmaceutical Companies, Beerse, Belgium
| | - Jolien Vanhove
- Janssen Research & Development, Janssen Pharmaceutical Companies, Beerse, Belgium.,Early Discovery Biology, Charles River Laboratories, Beerse, Belgium
| | - Bryan Severyn
- Janssen Research & Development, Janssen Pharmaceutical Companies, Springhouse, PA, United States
| | - Lore Verschueren
- Janssen Research & Development, Janssen Pharmaceutical Companies, Beerse, Belgium
| | - Frederik Pauwels
- Janssen Research & Development, Janssen Pharmaceutical Companies, Beerse, Belgium
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64
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Moon IY, Kim JW. Methylation profile of hepatitis B virus is not influenced by interferon α in human liver cancer cells. Mol Med Rep 2021; 24:715. [PMID: 34396432 PMCID: PMC8383030 DOI: 10.3892/mmr.2021.12354] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2020] [Accepted: 07/12/2021] [Indexed: 12/17/2022] Open
Abstract
Interferon (IFN) α is used for the treatment of chronic hepatitis B virus (HBV) infection, but the molecular mechanisms underlying its antiviral effect have not been fully elucidated. Epigenetic modifications regulate the transcriptional activity of covalently closed circular DNA (cccDNA) in cells with chronic HBV infection. IFN‑α has been shown to modify cccDNA‑bound histones, but it is not known whether the anti‑HBV effect of IFN‑α involves methylation of cccDNA. The present study aimed to determine whether IFN‑α induced methylation of HBV cccDNA in a cell‑based model in which HepG2 cells were directly infected with wild‑type HBV virions. Methylation status of HBV cccDNA was assessed using global DNA methylation ELISA assay, methylation‑specific PCR and bisulfite sequencing. IFN‑α suppressed HBV DNA and RNA transcripts, but methylation profiles were similar between the control and IFN‑α treated groups. Chromatin immunoprecipitation results revealed binding of DNA methyltransferases (DNMT) 3A and DNMT3B to HBV cccDNA and treatment with IFN‑α suppressed the recruitment of DNMT3B to cccDNA. Taken together, these results suggest that IFN‑α does not induce methylation of HBV cccDNA. Therefore, it was concluded that methylation is unlikely to contribute to the anti‑HBV effect of IFN‑α in HepG2 cells, and that alternative mechanisms need to be sought to enhance cccDNA methylation as a novel therapy against HBV.
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Affiliation(s)
- In Young Moon
- Department of Medicine, Seoul National University Bundang Hospital, Seongnam, Gyeonggi 13620, Republic of Korea
| | - Jin-Wook Kim
- Department of Medicine, Seoul National University Bundang Hospital, Seongnam, Gyeonggi 13620, Republic of Korea
- Department of Internal Medicine, Seoul National University College of Medicine, Seoul 03080, Republic of Korea
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65
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Martinez MG, Boyd A, Combe E, Testoni B, Zoulim F. Covalently closed circular DNA: The ultimate therapeutic target for curing HBV infections. J Hepatol 2021; 75:706-717. [PMID: 34051332 DOI: 10.1016/j.jhep.2021.05.013] [Citation(s) in RCA: 62] [Impact Index Per Article: 20.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/01/2021] [Revised: 05/03/2021] [Accepted: 05/07/2021] [Indexed: 12/16/2022]
Abstract
Current antiviral therapies, such as pegylated interferon-α and nucleos(t)ide analogues, effectively improve the quality of life of patients with chronic hepatitis B. However, they can only control the infection rather than curing infected hepatocytes. Complete HBV cure is hampered by the lack of therapies that can directly affect the viral minichromosome (in the form of covalently closed circular DNA [cccDNA]). Approaches currently under investigation in early clinical trials are aimed at achieving a functional cure, defined as the loss of HBsAg and undetectable HBV DNA levels in serum. However, achieving a complete HBV cure requires therapies that can directly target the cccDNA pool, either via degradation, lethal mutations or functional silencing. In this review, we discuss cutting-edge technologies that could lead to non-cytolytic direct cccDNA targeting and cure of infected hepatocytes.
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Affiliation(s)
| | - Anders Boyd
- Stichting HIV Monitoring, Amsterdam, the Netherlands; Department of Infectious Diseases, Research and Prevention, Public Health Service of Amsterdam, Amsterdam, the Netherlands
| | - Emmanuel Combe
- INSERM U1052, CNRS UMR-5286, Cancer Research Center of Lyon (CRCL), Lyon, 69008, France
| | - Barbara Testoni
- INSERM U1052, CNRS UMR-5286, Cancer Research Center of Lyon (CRCL), Lyon, 69008, France
| | - Fabien Zoulim
- INSERM U1052, CNRS UMR-5286, Cancer Research Center of Lyon (CRCL), Lyon, 69008, France; University of Lyon, Université Claude- Bernard (UCBL), 69008 Lyon, France; Hospices Civils de Lyon (HCL), 69002 Lyon, France.
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66
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Zhao F, Xie X, Tan X, Yu H, Tian M, Lv H, Qin C, Qi J, Zhu Q. The Functions of Hepatitis B Virus Encoding Proteins: Viral Persistence and Liver Pathogenesis. Front Immunol 2021; 12:691766. [PMID: 34456908 PMCID: PMC8387624 DOI: 10.3389/fimmu.2021.691766] [Citation(s) in RCA: 34] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2021] [Accepted: 07/26/2021] [Indexed: 12/14/2022] Open
Abstract
About 250 million people worldwide are chronically infected with Hepatitis B virus (HBV), contributing to a large burden on public health. Despite the existence of vaccines and antiviral drugs to prevent infection and suppress viral replication respectively, chronic hepatitis B (CHB) cure remains a remote treatment goal. The viral persistence caused by HBV is account for the chronic infection which increases the risk for developing liver cirrhosis and hepatocellular carcinoma (HCC). HBV virion utilizes various strategies to escape surveillance of host immune system therefore enhancing its replication, while the precise mechanisms involved remain elusive. Accumulating evidence suggests that the proteins encoded by HBV (hepatitis B surface antigen, hepatitis B core antigen, hepatitis B envelope antigen, HBx and polymerase) play an important role in viral persistence and liver pathogenesis. This review summarizes the major findings in functions of HBV encoding proteins, illustrating how these proteins affect hepatocytes and the immune system, which may open new venues for CHB therapies.
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Affiliation(s)
- Fenglin Zhao
- Shandong Provincial Hospital, Cheeloo College of Medicine, Shandong University, Jinan, China.,Shandong Provincial Engineering and Technological Research Center for Liver Diseases Prevention and Control, Jinan, China
| | - Xiaoyu Xie
- Shandong Provincial Hospital, Cheeloo College of Medicine, Shandong University, Jinan, China.,Shandong Provincial Engineering and Technological Research Center for Liver Diseases Prevention and Control, Jinan, China.,Shandong Provincial Hospital Affiliated to Shandong First Medical University, Jinan, China
| | - Xu Tan
- Shandong Provincial Hospital, Cheeloo College of Medicine, Shandong University, Jinan, China.,Shandong Provincial Hospital Affiliated to Shandong First Medical University, Jinan, China
| | - Hongli Yu
- Shandong Provincial Hospital, Cheeloo College of Medicine, Shandong University, Jinan, China.,Shandong Provincial Engineering and Technological Research Center for Liver Diseases Prevention and Control, Jinan, China
| | - Miaomiao Tian
- Shandong Provincial Engineering and Technological Research Center for Liver Diseases Prevention and Control, Jinan, China.,Shandong Provincial Hospital Affiliated to Shandong First Medical University, Jinan, China
| | - Huanran Lv
- Shandong Provincial Engineering and Technological Research Center for Liver Diseases Prevention and Control, Jinan, China.,Shandong Provincial Hospital Affiliated to Shandong First Medical University, Jinan, China
| | - Chengyong Qin
- Shandong Provincial Hospital, Cheeloo College of Medicine, Shandong University, Jinan, China.,Shandong Provincial Engineering and Technological Research Center for Liver Diseases Prevention and Control, Jinan, China.,Shandong Provincial Hospital Affiliated to Shandong First Medical University, Jinan, China
| | - Jianni Qi
- Shandong Provincial Hospital, Cheeloo College of Medicine, Shandong University, Jinan, China.,Shandong Provincial Engineering and Technological Research Center for Liver Diseases Prevention and Control, Jinan, China.,Shandong Provincial Hospital Affiliated to Shandong First Medical University, Jinan, China
| | - Qiang Zhu
- Shandong Provincial Hospital, Cheeloo College of Medicine, Shandong University, Jinan, China.,Shandong Provincial Engineering and Technological Research Center for Liver Diseases Prevention and Control, Jinan, China.,Shandong Provincial Hospital Affiliated to Shandong First Medical University, Jinan, China.,The First Affiliated Hospital of Xinjiang Medical University, Urumqi, China
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67
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Lucifora J, Pastor F, Charles É, Pons C, Auclair H, Fusil F, Rivoire M, Cosset FL, Durantel D, Salvetti A. Evidence for long-term association of virion-delivered HBV core protein with cccDNA independently of viral protein production. JHEP Rep 2021; 3:100330. [PMID: 34409278 PMCID: PMC8363821 DOI: 10.1016/j.jhepr.2021.100330] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/19/2021] [Revised: 06/02/2021] [Accepted: 06/21/2021] [Indexed: 01/05/2023] Open
Abstract
Background & Aims HBV persists in the nucleus of infected hepatocytes as a covalently closed circular DNA (cccDNA) episome that constitutes the template for viral RNA and protein synthesis. Both HBx and HBc (core) viral proteins associate with cccDNA but, while HBx is required for viral transcription, the role of HBc is still unclear. The aim of this study was to determine if HBc derived from incoming nucleocapsid can associate with cccDNA before the onset of viral transcription and protein production. Methods Chromatin immunoprecipitation assays were performed in native conditions. In addition, differentiated HepaRG (dHepaRG) cells infected with HBx-deficient HBV were used to investigate if HBc delivered by incoming virions can associate with cccDNA. Results Our results indicate that HBc can associate with cccDNA in the absence of viral transcription and de novo protein synthesis. In dHepaRG cells, this association is stable for at least 6 weeks. Conclusion These results suggest that virion-delivered HBc may participate at an early stage of cccDNA formation and/or transcription. Lay summary The hepatitis B virus genome is released into the nucleoplasm of infected cells after disassembly of the viral nucleocapsids at the nuclear membrane. Herein, we show for the first time that virion-delivered hepatitis B core protein, a component of the viral capsid, can stably associate with integrated viral DNA. The HBV episome (cccDNA) is formed in the nucleus following disassembly of incoming nucleocapsids. Native ChIP analysis indicates that virion-delivered HBc proteins can stably associate with cccDNA. Association of virion-delivered HBc does not require de novo viral protein synthesis. These results suggest that virion-delivered HBc may participate in cccDNA formation and/or transcriptional regulation.
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Key Words
- CAM
- ChIP
- ChIP, chromatin immunoprecipitation
- FA, formaldehyde
- H3K27Ac, histone 3 lysine 27 acetylation
- HBVΔX, HBx-deficient HBV
- HBc
- HBc, HBV core protein
- Hepatitis B Virus
- HuHep, liver-humanized mice
- PHHs, primary human hepatocytes
- cccDNA
- cccDNA, covalently closed circular DNA
- dHepaRG, differentiated HepaRG cells
- rcDNA, relaxed circular DNA
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Affiliation(s)
- Julie Lucifora
- CIRI - Centre International de Recherche en Infectiologie, Univ Lyon, Université Claude Bernard Lyon 1, Inserm, U1111, CNRS, UMR5308, ENS Lyon, F-69007 Lyon, France.,Past affiliation: INSERM, U1052, Cancer Research Center of Lyon (CRCL), University of Lyon (UCBL1), CNRS UMR_5286, Centre Léon Bérard, Lyon, France
| | - Florentin Pastor
- CIRI - Centre International de Recherche en Infectiologie, Univ Lyon, Université Claude Bernard Lyon 1, Inserm, U1111, CNRS, UMR5308, ENS Lyon, F-69007 Lyon, France
| | - Émilie Charles
- CIRI - Centre International de Recherche en Infectiologie, Univ Lyon, Université Claude Bernard Lyon 1, Inserm, U1111, CNRS, UMR5308, ENS Lyon, F-69007 Lyon, France
| | - Caroline Pons
- CIRI - Centre International de Recherche en Infectiologie, Univ Lyon, Université Claude Bernard Lyon 1, Inserm, U1111, CNRS, UMR5308, ENS Lyon, F-69007 Lyon, France.,Past affiliation: INSERM, U1052, Cancer Research Center of Lyon (CRCL), University of Lyon (UCBL1), CNRS UMR_5286, Centre Léon Bérard, Lyon, France
| | - Héloïse Auclair
- Past affiliation: INSERM, U1052, Cancer Research Center of Lyon (CRCL), University of Lyon (UCBL1), CNRS UMR_5286, Centre Léon Bérard, Lyon, France
| | - Floriane Fusil
- CIRI - Centre International de Recherche en Infectiologie, Univ Lyon, Université Claude Bernard Lyon 1, Inserm, U1111, CNRS, UMR5308, ENS Lyon, F-69007 Lyon, France
| | | | - François-Loïc Cosset
- CIRI - Centre International de Recherche en Infectiologie, Univ Lyon, Université Claude Bernard Lyon 1, Inserm, U1111, CNRS, UMR5308, ENS Lyon, F-69007 Lyon, France
| | - David Durantel
- CIRI - Centre International de Recherche en Infectiologie, Univ Lyon, Université Claude Bernard Lyon 1, Inserm, U1111, CNRS, UMR5308, ENS Lyon, F-69007 Lyon, France
| | - Anna Salvetti
- CIRI - Centre International de Recherche en Infectiologie, Univ Lyon, Université Claude Bernard Lyon 1, Inserm, U1111, CNRS, UMR5308, ENS Lyon, F-69007 Lyon, France
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68
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Ligat G, Verrier ER, Nassal M, Baumert TF. Hepatitis B virus-host interactions and novel targets for viral cure. Curr Opin Virol 2021; 49:41-51. [PMID: 34029994 PMCID: PMC7613419 DOI: 10.1016/j.coviro.2021.04.009] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2021] [Revised: 04/22/2021] [Accepted: 04/23/2021] [Indexed: 02/06/2023]
Abstract
Chronic infection with HBV is a major cause of advanced liver disease and hepatocellular carcinoma. Nucleos(t)ide analogues effectively control HBV replication but viral cure is rare. Hence treatment has often to be administered for an indefinite duration, increasing the risk for selection of drug resistant virus variants. PEG-interferon-α-based therapies can sometimes cure infection but suffer from a low response rate and severe side-effects. CHB is characterized by the persistence of a nuclear covalently closed circular DNA (cccDNA), which is not targeted by approved drugs. Targeting host factors which contribute to the viral life cycle provides new opportunities for the development of innovative therapeutic strategies aiming at HBV cure. An improved understanding of the host immune system has resulted in new potentially curative candidate approaches. Here, we review the recent advances in understanding HBV-host interactions and highlight how this knowledge contributes to exploiting host-targeting strategies for a viral cure.
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Affiliation(s)
- Gaëtan Ligat
- Université de Strasbourg, F-67000 Strasbourg, France; Inserm, Institut de Recherche sur les Maladies Virales et Hépatiques UMRS 1110, F-67000 Strasbourg, France.
| | - Eloi R Verrier
- Université de Strasbourg, F-67000 Strasbourg, France; Inserm, Institut de Recherche sur les Maladies Virales et Hépatiques UMRS 1110, F-67000 Strasbourg, France.
| | - Michael Nassal
- University Hospital Freiburg, Dept. of Internal Medicine 2/Molecular Biology, D79106 Freiburg, Germany.
| | - Thomas F Baumert
- Université de Strasbourg, F-67000 Strasbourg, France; Inserm, Institut de Recherche sur les Maladies Virales et Hépatiques UMRS 1110, F-67000 Strasbourg, France; Institut Hospitalo-Universitaire, Pôle Hépato-digestif, Nouvel Hôpital Civil, 67000 Strasbourg, France.
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69
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Wei L, Ploss A. Mechanism of Hepatitis B Virus cccDNA Formation. Viruses 2021; 13:v13081463. [PMID: 34452329 PMCID: PMC8402782 DOI: 10.3390/v13081463] [Citation(s) in RCA: 46] [Impact Index Per Article: 15.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2021] [Revised: 07/14/2021] [Accepted: 07/21/2021] [Indexed: 02/06/2023] Open
Abstract
Hepatitis B virus (HBV) remains a major medical problem affecting at least 257 million chronically infected patients who are at risk of developing serious, frequently fatal liver diseases. HBV is a small, partially double-stranded DNA virus that goes through an intricate replication cycle in its native cellular environment: human hepatocytes. A critical step in the viral life-cycle is the conversion of relaxed circular DNA (rcDNA) into covalently closed circular DNA (cccDNA), the latter being the major template for HBV gene transcription. For this conversion, HBV relies on multiple host factors, as enzymes capable of catalyzing the relevant reactions are not encoded in the viral genome. Combinations of genetic and biochemical approaches have produced findings that provide a more holistic picture of the complex mechanism of HBV cccDNA formation. Here, we review some of these studies that have helped to provide a comprehensive picture of rcDNA to cccDNA conversion. Mechanistic insights into this critical step for HBV persistence hold the key for devising new therapies that will lead not only to viral suppression but to a cure.
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70
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Qu B, Brown RJP. Strategies to Inhibit Hepatitis B Virus at the Transcript Level. Viruses 2021; 13:v13071327. [PMID: 34372533 PMCID: PMC8310268 DOI: 10.3390/v13071327] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2021] [Revised: 07/02/2021] [Accepted: 07/06/2021] [Indexed: 12/11/2022] Open
Abstract
Approximately 240 million people are chronically infected with hepatitis B virus (HBV), despite four decades of effective HBV vaccination. During chronic infection, HBV forms two distinct templates responsible for viral transcription: (1) episomal covalently closed circular (ccc)DNA and (2) host genome-integrated viral templates. Multiple ubiquitous and liver-specific transcription factors are recruited onto these templates and modulate viral gene transcription. This review details the latest developments in antivirals that inhibit HBV gene transcription or destabilize viral transcripts. Notably, nuclear receptor agonists exhibit potent inhibition of viral gene transcription from cccDNA. Small molecule inhibitors repress HBV X protein-mediated transcription from cccDNA, while small interfering RNAs and single-stranded oligonucleotides result in transcript degradation from both cccDNA and integrated templates. These antivirals mediate their effects by reducing viral transcripts abundance, some leading to a loss of surface antigen expression, and they can potentially be added to the arsenal of drugs with demonstrable anti-HBV activity. Thus, these candidates deserve special attention for future repurposing or further development as anti-HBV therapeutics.
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Affiliation(s)
- Bingqian Qu
- Division of Veterinary Medicine, Paul Ehrlich Institute, 63225 Langen, Germany
- European Virus Bioinformatics Center, 07743 Jena, Germany
- Correspondence: (B.Q.); (R.J.P.B.)
| | - Richard J. P. Brown
- Division of Veterinary Medicine, Paul Ehrlich Institute, 63225 Langen, Germany
- Correspondence: (B.Q.); (R.J.P.B.)
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Singh P, Kairuz D, Arbuthnot P, Bloom K. Silencing hepatitis B virus covalently closed circular DNA: The potential of an epigenetic therapy approach. World J Gastroenterol 2021; 27:3182-3207. [PMID: 34163105 PMCID: PMC8218364 DOI: 10.3748/wjg.v27.i23.3182] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/29/2021] [Revised: 03/23/2021] [Accepted: 05/07/2021] [Indexed: 02/06/2023] Open
Abstract
Global prophylactic vaccination programmes have helped to curb new hepatitis B virus (HBV) infections. However, it is estimated that nearly 300 million people are chronically infected and have a high risk of developing hepatocellular carcinoma. As such, HBV remains a serious health priority and the development of novel curative therapeutics is urgently needed. Chronic HBV infection has been attributed to the persistence of the covalently closed circular DNA (cccDNA) which establishes itself as a minichromosome in the nucleus of hepatocytes. As the viral transcription intermediate, the cccDNA is responsible for producing new virions and perpetuating infection. HBV is dependent on various host factors for cccDNA formation and the minichromosome is amenable to epigenetic modifications. Two HBV proteins, X (HBx) and core (HBc) promote viral replication by modulating the cccDNA epigenome and regulating host cell responses. This includes viral and host gene expression, chromatin remodeling, DNA methylation, the antiviral immune response, apoptosis, and ubiquitination. Elimination of the cccDNA minichromosome would result in a sterilizing cure; however, this may be difficult to achieve. Epigenetic therapies could permanently silence the cccDNA minichromosome and promote a functional cure. This review explores the cccDNA epigenome, how host and viral factors influence transcription, and the recent epigenetic therapies and epigenome engineering approaches that have been described.
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Affiliation(s)
- Prashika Singh
- Wits/SAMRC Antiviral Gene Therapy Research Unit, School of Pathology, University of the Witwatersrand, Johannesburg 2050, Gauteng, South Africa
| | - Dylan Kairuz
- Wits/SAMRC Antiviral Gene Therapy Research Unit, School of Pathology, University of the Witwatersrand, Johannesburg 2050, Gauteng, South Africa
| | - Patrick Arbuthnot
- Wits/SAMRC Antiviral Gene Therapy Research Unit, School of Pathology, University of the Witwatersrand, Johannesburg 2050, Gauteng, South Africa
| | - Kristie Bloom
- Wits/SAMRC Antiviral Gene Therapy Research Unit, School of Pathology, University of the Witwatersrand, Johannesburg 2050, Gauteng, South Africa
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Early Steps of Hepatitis B Life Cycle: From Capsid Nuclear Import to cccDNA Formation. Viruses 2021; 13:v13050757. [PMID: 33925977 PMCID: PMC8145197 DOI: 10.3390/v13050757] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2021] [Revised: 04/22/2021] [Accepted: 04/23/2021] [Indexed: 02/06/2023] Open
Abstract
Hepatitis B virus (HBV) remains a major public health concern, with more than 250 million chronically infected people who are at high risk of developing liver diseases, including cirrhosis and hepatocellular carcinoma. Although antiviral treatments efficiently control virus replication and improve liver function, they cannot cure HBV infection. Viral persistence is due to the maintenance of the viral circular episomal DNA, called covalently closed circular DNA (cccDNA), in the nuclei of infected cells. cccDNA not only resists antiviral therapies, but also escapes innate antiviral surveillance. This viral DNA intermediate plays a central role in HBV replication, as cccDNA is the template for the transcription of all viral RNAs, including pregenomic RNA (pgRNA), which in turn feeds the formation of cccDNA through a step of reverse transcription. The establishment and/or expression of cccDNA is thus a prime target for the eradication of HBV. In this review, we provide an update on the current knowledge on the initial steps of HBV infection, from the nuclear import of the nucleocapsid to the formation of the cccDNA.
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Maepa MB, Bloom K, Ely A, Arbuthnot P. Hepatitis B virus: promising drug targets and therapeutic implications. Expert Opin Ther Targets 2021; 25:451-466. [PMID: 33843412 DOI: 10.1080/14728222.2021.1915990] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Introduction: Current therapy for infection with hepatitis B virus (HBV) rarely clears the virus, and viremia commonly resurges following treatment withdrawal. To prevent serious complications of the infection, research has been aimed at identifying new viral and host targets that can be exploited to inactivate HBV replication.Areas covered: This paper reviews the use of these new molecular targets to advance anti-HBV therapy. Emphasis is on appraising data from pre-clinical and early clinical studies described in journal articles published during the past 10 years and available from PubMed.Expert opinion: The wide range of viral and host factors that can be targeted to disable HBV is impressive and improved insight into HBV molecular biology continues to provide the basis for new drug design. In addition to candidate therapies that have direct or indirect actions on HBV covalently closed circular DNA (cccDNA), compounds that inhibit HBsAg secretion, viral entry, destabilize viral RNA and effect enhanced immune responses to HBV show promise. Preclinical and clinical evaluation of drug candidates, as well as investigating use of treatment combinations, are encouraging. The field is poised at an interesting stage and indications are that reliably achieving functional cure from HBV infection is a tangible goal.
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Affiliation(s)
- Mohube Betty Maepa
- School of Pathology, Faculty of Health Sciences, Wits/SAMRC Antiviral Gene Therapy Research Unit, University of the Witwatersrand, Johannesburg, South Africa
| | - Kristie Bloom
- School of Pathology, Faculty of Health Sciences, Wits/SAMRC Antiviral Gene Therapy Research Unit, University of the Witwatersrand, Johannesburg, South Africa
| | - Abdullah Ely
- School of Pathology, Faculty of Health Sciences, Wits/SAMRC Antiviral Gene Therapy Research Unit, University of the Witwatersrand, Johannesburg, South Africa
| | - Patrick Arbuthnot
- School of Pathology, Faculty of Health Sciences, Wits/SAMRC Antiviral Gene Therapy Research Unit, University of the Witwatersrand, Johannesburg, South Africa
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74
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Goh ZY, Ren EC, Ko HL. Intracellular interferon signalling pathways as potential regulators of covalently closed circular DNA in the treatment of chronic hepatitis B. World J Gastroenterol 2021; 27:1369-1391. [PMID: 33911462 PMCID: PMC8047536 DOI: 10.3748/wjg.v27.i14.1369] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/21/2021] [Revised: 02/23/2021] [Accepted: 03/17/2021] [Indexed: 02/06/2023] Open
Abstract
Infection with the hepatitis B virus (HBV) is still a major global health threat as 250 million people worldwide continue to be chronically infected with the virus. While patients may be treated with nucleoside/nucleotide analogues, this only suppresses HBV titre to sub-detection levels without eliminating the persistent HBV covalently closed circular DNA (cccDNA) genome. As a result, HBV infection cannot be cured, and the virus reactivates when conditions are favorable. Interferons (IFNs) are cytokines known to induce powerful antiviral mechanisms that clear viruses from infected cells. They have been shown to induce cccDNA clearance, but their use in the treatment of HBV infection is limited as HBV-targeting immune cells are exhausted and HBV has evolved multiple mechanisms to evade and suppress IFN signalling. Thus, to fully utilize IFN-mediated intracellular mechanisms to effectively eliminate HBV, instead of direct IFN administration, novel strategies to sustain IFN-mediated anti-cccDNA and antiviral mechanisms need to be developed. This review will consolidate what is known about how IFNs act to achieve its intracellular antiviral effects and highlight the critical interferon-stimulated gene targets and effector mechanisms with potent anti-cccDNA functions. These include cccDNA degradation by APOBECs and cccDNA silencing and transcription repression by epigenetic modifications. In addition, the mechanisms that HBV employs to disrupt IFN signalling will be discussed. Drugs that have been developed or are in the pipeline for components of the IFN signalling pathway and HBV targets that detract IFN signalling mechanisms will also be identified and discussed for utility in the treatment of HBV infections. Together, these will provide useful insights into design strategies that specifically target cccDNA for the eradication of HBV.
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Affiliation(s)
- Zhi Yi Goh
- Singapore Immunology Network, Agency for Science, Technology and Research, Singapore 138648, Singapore
- Integrative Sciences and Engineering Programme, NUS Graduate School, National University of Singapore, Singapore 119077, Singapore
| | - Ee Chee Ren
- Singapore Immunology Network, Agency for Science, Technology and Research, Singapore 138648, Singapore
- Department of Microbiology and Immunology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore 119260, Singapore
| | - Hui Ling Ko
- Singapore Immunology Network, Agency for Science, Technology and Research, Singapore 138648, Singapore
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Wang G, Guan J, Khan NU, Li G, Shao J, Zhou Q, Xu L, Huang C, Deng J, Zhu H, Chen Z. Potential capacity of interferon-α to eliminate covalently closed circular DNA (cccDNA) in hepatocytes infected with hepatitis B virus. Gut Pathog 2021; 13:22. [PMID: 33845868 PMCID: PMC8040234 DOI: 10.1186/s13099-021-00421-9] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/08/2021] [Accepted: 04/01/2021] [Indexed: 12/14/2022] Open
Abstract
Interferon-alpha (IFN-α) and nucleot(s)ide analogs (NAs) are first-line drugs for the treatment of chronic hepatitis B virus (HBV) infections. Generally, NAs target the reverse transcription of HBV pregenomic RNA, but they cannot eliminate covalently-closed-circular DNA (cccDNA). Although effective treatment with NAs can dramatically decrease HBV proteins and DNA loads, and even promote serological conversion, cccDNA persists in the nucleus of hepatocytes due to the lack of effective anti-cccDNA drugs. Of the medications currently available, only IFN-α can potentially target cccDNA. However, the clinical effects of eradicating cccDNA using IFN-α in the hepatocytes of patients with HBV are not proficient as well as expected and are not well understood. Herein, we review the anti-HBV mechanisms of IFN-α involving cccDNA modification as the most promising approaches to cure HBV infection. We expect to find indications of promising areas of research that require further study to eliminate cccDNA of HBV in patients.
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Affiliation(s)
- Gang Wang
- State Key Laboratory for Diagnosis and Treatment of Infectious Diseases, Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, The First Affiliated Hospital, College of Medicine, National Clinical Research Center for Infectious Diseases, Zhejiang University School of Medicine, 79 Qingchun Road, Hangzhou, 310003, Zhejiang, China
| | - Jun Guan
- State Key Laboratory for Diagnosis and Treatment of Infectious Diseases, Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, The First Affiliated Hospital, College of Medicine, National Clinical Research Center for Infectious Diseases, Zhejiang University School of Medicine, 79 Qingchun Road, Hangzhou, 310003, Zhejiang, China
| | - Nazif U Khan
- State Key Laboratory for Diagnosis and Treatment of Infectious Diseases, Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, The First Affiliated Hospital, College of Medicine, National Clinical Research Center for Infectious Diseases, Zhejiang University School of Medicine, 79 Qingchun Road, Hangzhou, 310003, Zhejiang, China
| | - Guojun Li
- Institute for Hepatology, Shenzhen Third People's Hospital, National Clinical Research Center for Infectious Disease, Shenzhen, 518112, Guangdong, China.,The Second Affiliated Hospital, School of Medicine, Southern University of Science and Technology, 518112, Shenzhen, China
| | - Junwei Shao
- State Key Laboratory for Diagnosis and Treatment of Infectious Diseases, Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, The First Affiliated Hospital, College of Medicine, National Clinical Research Center for Infectious Diseases, Zhejiang University School of Medicine, 79 Qingchun Road, Hangzhou, 310003, Zhejiang, China
| | - Qihui Zhou
- State Key Laboratory for Diagnosis and Treatment of Infectious Diseases, Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, The First Affiliated Hospital, College of Medicine, National Clinical Research Center for Infectious Diseases, Zhejiang University School of Medicine, 79 Qingchun Road, Hangzhou, 310003, Zhejiang, China
| | - Lichen Xu
- State Key Laboratory for Diagnosis and Treatment of Infectious Diseases, Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, The First Affiliated Hospital, College of Medicine, National Clinical Research Center for Infectious Diseases, Zhejiang University School of Medicine, 79 Qingchun Road, Hangzhou, 310003, Zhejiang, China
| | - Chunhong Huang
- State Key Laboratory for Diagnosis and Treatment of Infectious Diseases, Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, The First Affiliated Hospital, College of Medicine, National Clinical Research Center for Infectious Diseases, Zhejiang University School of Medicine, 79 Qingchun Road, Hangzhou, 310003, Zhejiang, China
| | - Jingwen Deng
- State Key Laboratory for Diagnosis and Treatment of Infectious Diseases, Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, The First Affiliated Hospital, College of Medicine, National Clinical Research Center for Infectious Diseases, Zhejiang University School of Medicine, 79 Qingchun Road, Hangzhou, 310003, Zhejiang, China
| | - Haihong Zhu
- State Key Laboratory for Diagnosis and Treatment of Infectious Diseases, Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, The First Affiliated Hospital, College of Medicine, National Clinical Research Center for Infectious Diseases, Zhejiang University School of Medicine, 79 Qingchun Road, Hangzhou, 310003, Zhejiang, China
| | - Zhi Chen
- State Key Laboratory for Diagnosis and Treatment of Infectious Diseases, Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, The First Affiliated Hospital, College of Medicine, National Clinical Research Center for Infectious Diseases, Zhejiang University School of Medicine, 79 Qingchun Road, Hangzhou, 310003, Zhejiang, China.
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76
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Wooddell CI, Gehring AJ, Yuen MF, Given BD. RNA Interference Therapy for Chronic Hepatitis B Predicts the Importance of Addressing Viral Integration When Developing Novel Cure Strategies. Viruses 2021; 13:v13040581. [PMID: 33808298 PMCID: PMC8065501 DOI: 10.3390/v13040581] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2021] [Revised: 03/26/2021] [Accepted: 03/29/2021] [Indexed: 12/12/2022] Open
Abstract
Chronic hepatitis B infection remains a globally important cause of morbidity and mortality and has recently undergone a renaissance in therapeutic interest with increased pre-clinical and clinical testing of new drug classes. One of the first new classes in the clinic was RNA interference agents, which have the potential to impact the entire viral life cycle by reducing all virus-produced mRNA. Early clinical testing with the first of these agents in the clinic, ARC-520, demonstrated that rapid and deep reductions in viral proteins, RNA and DNA could be produced with this approach, but also the surprising insight that HBsAg production from incomplete HBV DNA integrated into the host genome appears to play a heretofore unappreciated and important role in maintaining circulating HBsAg, thought to play a fundamental role in preventing host clearance of the virus. Thus, accounting for viral DNA integration in novel HBV treatment approaches may prove to be essential to achieving successful finite therapies of this difficult to treat chronic infection.
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Affiliation(s)
- Christine I. Wooddell
- Arrowhead Pharmaceuticals, 502 South Rosa Road, Madison, WI 53719, USA;
- Correspondence: ; Tel.: +1-608-316-3930
| | - Adam J. Gehring
- Toronto Centre for Liver Disease, Toronto General Hospital Research Institute, University Health Network, Toronto, ON M5G 1L7, Canada;
| | - Man-Fung Yuen
- Department of Medicine, The University of Hong Kong, Queen Mary Hospital, Hong Kong, China;
| | - Bruce D. Given
- Arrowhead Pharmaceuticals, 502 South Rosa Road, Madison, WI 53719, USA;
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77
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Wu YH, Yang Y, Chen CH, Hsiao CJ, Li TN, Liao KJ, Watashi K, Chen BS, Wang LHC. Aerobic glycolysis supports hepatitis B virus protein synthesis through interaction between viral surface antigen and pyruvate kinase isoform M2. PLoS Pathog 2021; 17:e1008866. [PMID: 33720996 PMCID: PMC8009439 DOI: 10.1371/journal.ppat.1008866] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2020] [Revised: 03/30/2021] [Accepted: 02/26/2021] [Indexed: 12/27/2022] Open
Abstract
As an intracellular pathogen, the reproduction of the hepatitis B virus (HBV) depends on the occupancy of host metabolism machinery. Here we test a hypothesis if HBV may govern intracellular biosynthesis to achieve a productive reproduction. To test this hypothesis, we set up an affinity purification screen for host factors that interact with large viral surface antigens (LHBS). This identified pyruvate kinase isoform M2 (PKM2), a key regulator of glucose metabolism, as a binding partner of viral surface antigens. We showed that the expression of viral LHBS affected oligomerization of PKM2 in hepatocytes, thereby increasing glucose consumption and lactate production, a phenomenon known as aerobic glycolysis. Reduction of PKM2 activity was also validated in several different models, including HBV-infected HepG2-NTCP-C4 cells, adenovirus mediated HBV gene transduction and transfection with a plasmid containing complete HBV genome on HuH-7 cells. We found the recovery of PKM2 activity in hepatocytes by chemical activators, TEPP-46 or DASA-58, reduced expressions of viral surface and core antigens. In addition, reduction of glycolysis by culturing in low-glucose condition or treatment with 2-deoxyglucose also decreased expressions of viral surface antigen, without affecting general host proteins. Finally, TEPP-46 largely suppressed proliferation of LHBS-positive cells on 3-dimensional agarose plates, but showed no effect on the traditional 2-dimensional cell culture. Taken together, these results indicate that HBV-induced metabolic switch may support its own translation in hepatocytes. In addition, aerobic glycolysis is likely essential for LHBS-mediated oncogenesis. Accordingly, restriction of glucose metabolism may be considered as a novel strategy to restrain viral protein synthesis and subsequent oncogenesis during chronic HBV infection.
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Affiliation(s)
- Yi-Hsuan Wu
- Institute of Molecular and Cellular Biology, National Tsing Hua University, Hsinchu, Taiwan
| | - Yi Yang
- Institute of Molecular and Cellular Biology, National Tsing Hua University, Hsinchu, Taiwan
| | - Ching-Hung Chen
- Institute of Molecular and Cellular Biology, National Tsing Hua University, Hsinchu, Taiwan
| | - Chia-Jen Hsiao
- Institute of Molecular and Cellular Biology, National Tsing Hua University, Hsinchu, Taiwan
- Division of Gastroenterology, New Taipei City Hospital, New Taipei City, Taiwan
| | - Tian-Neng Li
- Institute of Molecular and Cellular Biology, National Tsing Hua University, Hsinchu, Taiwan
| | - Kuan-Ju Liao
- Institute of Bioinformatics and Structural Biology, National Tsing Hua University, Hsinchu, Taiwan
| | - Koichi Watashi
- Department of Virology II, National Institute of Infectious Diseases, Tokyo, Japan
| | - Bor-Sen Chen
- Department of Electrical Engineering, National Tsing Hua University, Hsinchu, Taiwan
| | - Lily Hui-Ching Wang
- Institute of Molecular and Cellular Biology, National Tsing Hua University, Hsinchu, Taiwan
- * E-mail:
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78
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Insights into the roles of histone chaperones in nucleosome assembly and disassembly in virus infection. Virus Res 2021; 297:198395. [PMID: 33737155 DOI: 10.1016/j.virusres.2021.198395] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2020] [Revised: 03/10/2021] [Accepted: 03/11/2021] [Indexed: 11/23/2022]
Abstract
Nucleosomes are assembled or disassembled with the aid of histone chaperones in a cell. Viruses can exist either as minichromosomes/episomes or can integrate into the host genome and in both the cases the viral proteins interact and manipulate the cellular nucleosome assembly machinery to ensure their survival and propagation. Recent studies have provided insight into the mechanism and role of histone chaperones in nucleosome assembly and disassembly on the virus genome. Further, the interactions between viral proteins and histone chaperones have been implicated in the integration of the virus genome into the host genome. This review highlights the recent progress and future challenges in understanding the role of histone chaperones in viruses with DNA or RNA genome and their role in governing viral pathogenesis.
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79
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Rao S, Hossain T, Mahmoudi T. 3D human liver organoids: An in vitro platform to investigate HBV infection, replication and liver tumorigenesis. Cancer Lett 2021; 506:35-44. [PMID: 33675983 DOI: 10.1016/j.canlet.2021.02.024] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2020] [Revised: 02/18/2021] [Accepted: 02/25/2021] [Indexed: 02/07/2023]
Abstract
Hepatitis B Virus (HBV) infection is a leading cause of chronic liver cirrhosis and hepatocellular carcinoma (HCC) with an estimated 400 million people infected worldwide. The precise molecular mechanisms underlying HBV replication and tumorigenesis have remained largely uncharacterized due to the lack of a primary cell model to study HBV, a virus that exhibits stringent host species and cell-type specificity. Organoid technology has recently emerged as a powerful tool to investigate human diseases in a primary 3D cell-culture system that maintains the organisation and functionality of the tissue of origin. In this review, we describe the utilisation of human liver organoid platforms to study HBV. We first present the different categories of liver organoids and their demonstrated ability to support the complete HBV replication cycle. We then discuss the potential applications of liver organoids in investigating HBV infection and replication, related tumorigenesis and novel HBV-directed therapies. Liver organoids can be genetically modified, patient-derived, expanded and biobanked, thereby serving as a clinically-relevant, human, primary cell-derived platform to investigate HBV. Finally, we provide insights into the future applications of this powerful technology in the context of HBV-infection and HCC.
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Affiliation(s)
- Shringar Rao
- Department of Biochemistry, Erasmus University Medical Centre, PO Box 2040, 3000, CA, 9 Rotterdam, the Netherlands
| | - Tanvir Hossain
- Department of Biochemistry, Erasmus University Medical Centre, PO Box 2040, 3000, CA, 9 Rotterdam, the Netherlands
| | - Tokameh Mahmoudi
- Department of Biochemistry, Erasmus University Medical Centre, PO Box 2040, 3000, CA, 9 Rotterdam, the Netherlands; Department of Pathology, Erasmus University Medical Centre, PO Box 2040, 3000, CA, Rotterdam, the Netherlands; Department of Urology, Erasmus University Medical Centre, PO Box 2040, 3000, CA, Rotterdam, the Netherlands.
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80
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D’Arienzo V, Magri A, Harris JM, Wing PAC, Ko C, Rubio CO, Revill PA, Protzer U, Balfe P, McKeating JA. A PCR assay to quantify patterns of HBV transcription. J Gen Virol 2021; 102:001373. [PMID: 31846416 PMCID: PMC7610515 DOI: 10.1099/jgv.0.001373] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2019] [Accepted: 11/27/2019] [Indexed: 12/11/2022] Open
Abstract
Hepatitis B virus (HBV) is the prototype member of the family Hepadnaviridae and replicates via episomal copies of a covalently closed circular DNA (cccDNA) genome of approximately 3.2 kb. The chromatinization of this small viral genome, with overlapping open reading frames and regulatory elements, suggests an important role for epigenetic pathways to regulate HBV transcription. However, the host pathways that regulate HBV transcription and the temporal nature of promoter usage in infected cells are not well understood, in part due to the compact genome structure and overlapping open reading frames. To address this we developed a simple and cost-effective PCR assay to quantify the major viral RNAs and validated this technique using current state-of-art de novo HBV infection model systems. Our PCR method is three orders of magnitude more sensitive than Northern blot and requires relatively small amounts of starting material, making this an attractive tool for assessing HBV transcription.
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Affiliation(s)
- Valentina D’Arienzo
- Nuffield Department of Medicine, University of Oxford, Old Road Campus, Roosevelt Drive, Oxford, UK
| | - Andrea Magri
- Nuffield Department of Medicine, University of Oxford, Old Road Campus, Roosevelt Drive, Oxford, UK
| | - James M. Harris
- Nuffield Department of Medicine, University of Oxford, Old Road Campus, Roosevelt Drive, Oxford, UK
| | - Peter A. C. Wing
- Nuffield Department of Medicine, University of Oxford, Old Road Campus, Roosevelt Drive, Oxford, UK
| | - Chunkyu Ko
- Institute of Virology, Technische Universität, München/Helmholtz Zentrum München, Germany
| | - Claudia Orbegozo Rubio
- Nuffield Department of Medicine, University of Oxford, Old Road Campus, Roosevelt Drive, Oxford, UK
| | - Peter A. Revill
- Victorian Infectious Diseases Reference Laboratory, Royal Melbourne Hospital at the Peter Doherty Institute of Infection and Immunity, Melbourne, Australia
- Department of Microbiology and Immunology, University of Melbourne, Melbourne, Australia
| | - Ulrike Protzer
- Institute of Virology, Technische Universität, München/Helmholtz Zentrum München, Germany
- German Center for Infection Research (DZIF), Munich partner site, Munich, Germany
| | - Peter Balfe
- Nuffield Department of Medicine, University of Oxford, Old Road Campus, Roosevelt Drive, Oxford, UK
- Institute of Immunology and Immunotherapy, University of Birmingham, UK
| | - Jane A. McKeating
- Nuffield Department of Medicine, University of Oxford, Old Road Campus, Roosevelt Drive, Oxford, UK
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81
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Abstract
Hepatitis B virus (HBV) core protein (Cp) can be found in the nucleus and cytoplasm of infected hepatocytes; however, it preferentially segregates to a specific compartment correlating with disease status. Regulation of this intracellular partitioning of Cp remains obscure. In this paper, we report that cellular compartments are filled and vacated by Cp in a time- and concentration-dependent manner in both transfections and infections. At early times after transfection, Cp, in a dimeric state, preferentially localizes to the nucleolus. Later, the nucleolar compartment is emptied and Cp progresses to being predominantly nuclear, with a large fraction of the protein in an assembled state. Nuclear localization is followed by cell-wide distribution, and then Cp becomes exclusively cytoplasmic. The same trend in Cp movement is seen during an infection. Putative nucleolar retention signals have been identified and appear to be structure dependent. Export of Cp from the nucleus involves the CRM1 exportin. Time-dependent flux can be recapitulated by modifying Cp concentration, suggesting transitions are regulated by reaching a threshold concentration.
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82
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Abstract
Chronic infection of the liver by the hepatitis B virus (HBV) is associated with increased risk for developing hepatocellular carcinoma (HCC). A multitude of studies have investigated the mechanism of liver cancer pathogenesis due to chronic HBV infection. Chronic inflammation, expression of specific viral proteins such as HBx, the integration site of the viral genome into the host genome, and the viral genotype, are key players contributing to HCC pathogenesis. In addition, the genetic background of the host and exposure to environmental carcinogens are also predisposing parameters in hepatocarcinogenesis. Despite the plethora of studies, the molecular mechanism of HCC pathogenesis remains incompletely understood. In this review, the focus is on epigenetic mechanisms involved in the pathogenesis of HBV-associated HCC. Epigenetic mechanisms are dynamic molecular processes that regulate gene expression without altering the host DNA, acting by modifying the host chromatin structure via covalent post-translational histone modifications, changing the DNA methylation status, expression of non-coding RNAs such as microRNAs and long noncoding RNAs, and altering the spatial, 3-D organization of the chromatin of the virus-infected cell. Herein, studies are described that provide evidence in support of deregulation of epigenetic mechanisms in the HBV-infected/-replicating hepatocyte and their contribution to hepatocyte transformation. In contrast to genetic mutations which are permanent, epigenetic alterations are dynamic and reversible. Accordingly, the identification of essential molecular epigenetic targets involved in HBV-mediated HCC pathogenesis offers the opportunity for the design and development of novel epigenetic therapeutic approaches.
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Affiliation(s)
- Ourania Andrisani
- Department of Basic Medical Sciences and Purdue Center for Cancer Research, Purdue University, West Lafayette, IN 47907, USA
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83
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Zarreen F, Chakraborty S. Epigenetic regulation of geminivirus pathogenesis: a case of relentless recalibration of defence responses in plants. JOURNAL OF EXPERIMENTAL BOTANY 2020; 71:6890-6906. [PMID: 32869846 DOI: 10.1093/jxb/eraa406] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/27/2020] [Accepted: 08/27/2020] [Indexed: 06/11/2023]
Abstract
Geminiviruses constitute one of the largest families of plant viruses and they infect many economically important crops. The proteins encoded by the single-stranded DNA genome of these viruses interact with a wide range of host proteins to cause global dysregulation of cellular processes and help establish infection in the host. Geminiviruses have evolved numerous mechanisms to exploit host epigenetic processes to ensure the replication and survival of the viral genome. Here, we review our current knowledge of diverse epigenetic processes that have been implicated in the regulation of geminivirus pathogenesis, including DNA methylation, histone post-transcriptional modification, chromatin remodelling, and nucleosome repositioning. In addition, we discuss the currently limited evidence of host epigenetic defence responses that are aimed at counteracting geminivirus infection, and the potential for exploiting these responses for the generation of resistance against geminiviruses in crop species.
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Affiliation(s)
- Fauzia Zarreen
- Molecular Virology Laboratory, School of Life Sciences, Jawaharlal Nehru University, New Delhi, India
| | - Supriya Chakraborty
- Molecular Virology Laboratory, School of Life Sciences, Jawaharlal Nehru University, New Delhi, India
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84
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Yang B, Li B, Jia L, Jiang Y, Wang X, Jiang S, Du S, Ji X, Yang P. 3D landscape of Hepatitis B virus interactions with human chromatins. Cell Discov 2020; 6:95. [PMID: 33372176 PMCID: PMC7769987 DOI: 10.1038/s41421-020-00218-1] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2020] [Accepted: 08/26/2020] [Indexed: 12/18/2022] Open
Abstract
Hepatitis B viral (HBV) DNAs, including covalently closed circular DNA (cccDNA) and integrated HBV DNA forms, are considered to be primary contributors to the development and progression of HBV-associated liver diseases. However, it remains largely unclear how HBV DNAs communicate with human chromatin. Here we employed a highly sensitive technology, 3C-high-throughput genome-wide translocation sequencing (3C-HTGTS), to globally identify HBV DNA-host DNA contacts in cellular models of HBV infection. HBV DNA does not randomly position in host genome but instead preferentially establishes contacts with the host DNA at active chromatin regions. HBV DNA-host DNA contacts are significantly enriched at H3K4me1-marked regions modified by KMT2C/D; this histone modification is also observed in the HBV cccDNA mini-chromosome and strongly influences HBV transcription. On the other hand, chromatin loop formed by integrated HBV DNA with host genomic DNA was found in transcriptionally active regions. Furthermore, HBV infection influences host gene expression accompanied with HBV DNA-host DNA contacts. Our study provides a 3D landscape of spatial organization of cccDNA and integrated HBV DNA within the human genome, which lays the foundation for a better understanding of the mechanisms how HBV involves in liver disease development and progression.
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Affiliation(s)
- Bo Yang
- CAS Key Laboratory of Infection and Immunity, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, University of Chinese Academy of Sciences, Chinese Academy of Sciences, Beijing, 100101, China
| | - Boyuan Li
- Key Laboratory of Cell Proliferation and Differentiation of the Ministry of Education, School of Life Sciences, Peking-Tsinghua Center for Life Sciences, Peking University, Beijing, 100871, China
| | - Liyang Jia
- CAS Key Laboratory of Infection and Immunity, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, University of Chinese Academy of Sciences, Chinese Academy of Sciences, Beijing, 100101, China
| | - Yongpeng Jiang
- Key Laboratory of Cell Proliferation and Differentiation of the Ministry of Education, School of Life Sciences, Peking-Tsinghua Center for Life Sciences, Peking University, Beijing, 100871, China
| | - Xin Wang
- CAS Key Laboratory of Infection and Immunity, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, University of Chinese Academy of Sciences, Chinese Academy of Sciences, Beijing, 100101, China
| | - Shaodong Jiang
- CAS Key Laboratory of Infection and Immunity, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, University of Chinese Academy of Sciences, Chinese Academy of Sciences, Beijing, 100101, China
| | - Shunda Du
- Department of Liver Surgery, Peking Union Medical College (PUMC) Hospital, Chinese Academy of Medical Science and PUMC, Beijing, 100730, China
| | - Xiong Ji
- Key Laboratory of Cell Proliferation and Differentiation of the Ministry of Education, School of Life Sciences, Peking-Tsinghua Center for Life Sciences, Peking University, Beijing, 100871, China.
| | - Pengyuan Yang
- CAS Key Laboratory of Infection and Immunity, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, University of Chinese Academy of Sciences, Chinese Academy of Sciences, Beijing, 100101, China.
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85
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S6K1 inhibits HBV replication through inhibiting AMPK-ULK1 pathway and disrupting acetylation modification of H3K27. Life Sci 2020; 265:118848. [PMID: 33278383 DOI: 10.1016/j.lfs.2020.118848] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2020] [Revised: 11/19/2020] [Accepted: 11/27/2020] [Indexed: 01/01/2023]
Abstract
AIMS To investigated the effect of S6K1 on the replication and transcription of HBV DNA using multiple cell models. MAIN METHODS The pgRNA, total HBV RNA and HBV DNA level were detected by Real-time PCR. The HBcAg expression by Western blot and the activity of four HBV promoters, such as preS1, preS2/S, core, and X promoters by using dual luciferase reporter assay. Moreover, we determined S6K1 interacted with HBcAg in both cytoplasm and nucleus through Immunofluorescence, co-immunoprecipitation (CoIP) and Western blot. KEY FINDINGS S6K1 inhibited HBV DNA replication and cccDNA-dependent transcription in HBV-expressing stable cell lines. The mechanistic study revealed that S6K1 suppressed HBV DNA replication by inhibiting AMPK-ULK1 autophagy pathway, and the nuclear S6K1 suppressed HBV cccDNA-dependent transcription by inhibiting the acetylation modification of H3K27. In addition, HBV capsid protein (HBcAg) suppressed the phosphorylation level of S6K1Thr389 by interacting with S6K1, indicating a viral antagonism of S6K1-mediated antiviral mechanism. SIGNIFICANCE The p70 ribosomal S6 kinase (S6K1) is a serine/threonine protein kinase, and it plays a significant role in different cellular processes. It has been previously reported that S6K1 affects hepatitis B virus (HBV) replication but the underlying mechanism remains unclear. In this study, our data suggested that the activation of S6K1 restricts HBV replication through inhibiting AMPK-ULK1 autophagy pathway and H3K27 acetylation. These findings indicated that S6K1 might be a potential therapeutic target for HBV infection.
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86
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Hepatitis B virus Core protein nuclear interactome identifies SRSF10 as a host RNA-binding protein restricting HBV RNA production. PLoS Pathog 2020; 16:e1008593. [PMID: 33180834 PMCID: PMC7707522 DOI: 10.1371/journal.ppat.1008593] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2020] [Revised: 12/01/2020] [Accepted: 10/04/2020] [Indexed: 12/11/2022] Open
Abstract
Despite the existence of a preventive vaccine, chronic infection with Hepatitis B virus (HBV) affects more than 250 million people and represents a major global cause of hepatocellular carcinoma (HCC) worldwide. Current clinical treatments, in most of cases, do not eliminate viral genome that persists as a DNA episome in the nucleus of hepatocytes and constitutes a stable template for the continuous expression of viral genes. Several studies suggest that, among viral factors, the HBV core protein (HBc), well-known for its structural role in the cytoplasm, could have critical regulatory functions in the nucleus of infected hepatocytes. To elucidate these functions, we performed a proteomic analysis of HBc-interacting host-factors in the nucleus of differentiated HepaRG, a surrogate model of human hepatocytes. The HBc interactome was found to consist primarily of RNA-binding proteins (RBPs), which are involved in various aspects of mRNA metabolism. Among them, we focused our studies on SRSF10, a RBP that was previously shown to regulate alternative splicing (AS) in a phosphorylation-dependent manner and to control stress and DNA damage responses, as well as viral replication. Functional studies combining SRSF10 knockdown and a pharmacological inhibitor of SRSF10 phosphorylation (1C8) showed that SRSF10 behaves as a restriction factor that regulates HBV RNAs levels and that its dephosphorylated form is likely responsible for the anti-viral effect. Surprisingly, neither SRSF10 knock-down nor 1C8 treatment modified the splicing of HBV RNAs but rather modulated the level of nascent HBV RNA. Altogether, our work suggests that in the nucleus of infected cells HBc interacts with multiple RBPs that regulate viral RNA metabolism. Our identification of SRSF10 as a new anti-HBV restriction factor offers new perspectives for the development of new host-targeted antiviral strategies. Chronic infection with Hepatitis B virus (HBV) affects more than 250 million of people world-wide and is a major global cause of liver cancer. Current treatments lead to a significant reduction of viremia in patients. However, viral clearance is rarely obtained and the persistence of the HBV genome in the hepatocyte’s nucleus generates a stable source of viral RNAs and subsequently proteins which play important roles in immune escape mechanisms and liver disease progression. Therapies aiming at efficiently and durably eliminating viral gene expression are still required. In this study, we identified the nuclear partners of the HBV Core protein (HBc) to understand how this structural protein, responsible for capsid assembly in the cytoplasm, could also regulate viral gene expression. The HBc interactome was found to consist primarily of RNA-binding proteins (RBPs). One of these RBPs, SRSF10, was demonstrated to restrict HBV RNA levels and a drug, able to alter its phosphorylation, behaved as an antiviral compound capable of reducing viral gene expression. Altogether, this study sheds new light on novel regulatory functions of HBc and provides information relevant for the development of antiviral strategies aiming at preventing viral gene expression.
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87
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Dandri M, Petersen J. cccDNA Maintenance in Chronic Hepatitis B - Targeting the Matrix of Viral Replication. Infect Drug Resist 2020; 13:3873-3886. [PMID: 33149632 PMCID: PMC7605611 DOI: 10.2147/idr.s240472] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2020] [Accepted: 10/02/2020] [Indexed: 12/11/2022] Open
Abstract
Chronic hepatitis B is a numerically important cause of cirrhosis and hepatocellular carcinoma, despite an effective prophylactic vaccine and well-tolerated and effective oral antivirals. Both the incapacity of the immune system to clear hepatitis B virus (HBV) infection and the unique replication strategies adopted by HBV are considered key determinants of HBV chronicity. In this regard, the formation of the HBV DNA minichromosome, the covalently closed circular DNA (cccDNA), in the nucleus of infected hepatocytes, is essential not only for the production of all viral proteins but also for HBV persistence even after long-term antiviral therapy. Licensed polymerase inhibitors target the HBV reverse transcriptase activity, control the disease with long-term therapy but fail to eliminate the cccDNA. Consequently, the production of viral RNAs and proteins, including the hepatitis B surface antigen (HBsAg), is not abolished. Novel therapeutic efforts that are in the pipeline for early clinical trials explore novel targets and molecules. Such therapeutic efforts focus on achieving a functional cure, which is defined by the loss of HBsAg and undetectable HBV DNA levels in serum. Since a true cure of HBV infection requires the elimination of the cccDNA from infected cells, comprehension of the mechanisms implicated in cccDNA biogenesis, regulation and stability appears necessary to achieve HBV eradication. In this review, we will summarize the state of knowledge on cccDNA metabolism, focusing on insights suggesting potential weak points of the cccDNA that may be key for the development of therapeutic approaches and design of clinical trials aiming at lowering cccDNA loads and activity.
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Affiliation(s)
- Maura Dandri
- Department of Internal Medicine, University Medical Center Hamburg - Eppendorf, Hamburg, Germany.,German Center for Infection Research (DZIF), Hamburg-Luebeck-Borstel-Riems Site, Germany
| | - Joerg Petersen
- Institute for Interdisciplinary Medicine, Asklepios Klinik St Georg, University of Hamburg, Hamburg, Germany
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D e novo synthesis of hepatitis B virus nucleocapsids is dispensable for the maintenance and transcriptional regulation of cccDNA. JHEP Rep 2020; 3:100195. [PMID: 33385130 PMCID: PMC7771110 DOI: 10.1016/j.jhepr.2020.100195] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/21/2020] [Revised: 08/24/2020] [Accepted: 09/20/2020] [Indexed: 12/14/2022] Open
Abstract
Background & Aims Chronic HBV infection cannot be cured by current therapeutics owing to their limited ability to reduce covalently closed circular (ccc)DNA levels in the livers of infected individuals. Therefore, greater understanding of the molecular determinants of cccDNA formation and persistence is required. One key issue is the extent to which de novo nucleocapsid-mediated replenishment (reimport) contributes to cccDNA levels in an infected hepatocyte. Methods We engineered an infectious HBV mutant with a genome encoding a stop codon at position T67 in the HBV core open reading frame (ΔHBc HBV). Importantly, ΔHBc HBV virions cannot initiate nucleocapsid synthesis upon infection. Long-term in vitro HBV infection markers were followed for up for 9 weeks in HepG2-NTCP cells (A3 clone) and HBV DNA was quantified using a newly-developed, highly-precise PCR assay (cccDNA inversion quantitative PCR). Results ΔHBc and wild-type (WT) HBV resulted in comparable expression of HBV surface antigen (HBsAg), which could be blocked using the entry inhibitor Myrcludex B, confirming bona fide infection via the receptor sodium taurocholate cotransporting polypeptide (NTCP). In primary human hepatocytes, Huh7-NTCP, HepG2-NTCP, and HepaRG-NTCP cells, comparable copy numbers of cccDNA were formed. cccDNA levels, transcription of viral RNA, and HBsAg secretion remained comparably stable in WT and ΔHBc HBV-infected cells for at least 9 weeks. Conclusions Our results imply that de novo synthesised HBc plays a minor role in transcriptional regulation of cccDNA. Importantly, we show that initially-formed cccDNA is stable in hepatocytes without requiring continuous replenishment in in vitro infection systems and contribution from de novo DNA-containing nucleocapsids is not required. Thus, short-term therapeutic targeting of capsid-reimport is likely an inefficient strategy in eliminating cccDNA in chronically infected hepatocytes. Lay summary The hepatitis B virus can maintain itself in the liver for a patient's lifetime, causing liver injury and cancer. We have clarified exactly how it maintains itself in an infected cell. This now means we have a better idea at how to target the virus and cure a chronic infection. Covalently closed circular (ccc)DNA is key for maintaining chronic HBV infection. Virus core protein expression is not required for cccDNA formation, stability, or transcription within 9 weeks of in vitro infection. Our results suggest that targeting HBV core with short-term treatment is inefficient in clearing intrahepatic cccDNA. Viral entry inhibitors or capsid inhibitors could prevent breakthrough of novel HBV variants.
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Key Words
- ALT, alanine aminotransferase
- Antivirals
- Bulevirtide
- CIs, capsid inhibitors
- Capsid inhibitors
- Core protein
- Covalently closed circular DNA
- DHBV, duck hepatitis B virus
- HBV DNA integration
- HBV persistence
- HBV, hepatitis B virus
- HBcAg
- HBsAg, hepatitis B virus surface antigen
- Hepcludex
- Myrcludex B
- NC, naked capsids
- NTCP, sodium taurocholate cotransporting polypeptide
- NUCs, nucleos(t)ide analogues
- ORF, open reading frame
- PEG, polyethylene glycol
- PHH, primary human hepatocytes
- SN, supernatant
- VP, virions
- WT, wild-type
- cccDNA, covalently closed circular DNA
- dpi, days post inoculation
- mge, multiplicity of genomic equivalent
- pgRNA, pregenomic RNA
- rcDNA, relaxed circular DNA
- vge, viral genome equivalents
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89
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Occult hepatitis B infection and hepatocellular carcinoma: Epidemiology, virology, hepatocarcinogenesis and clinical significance. J Hepatol 2020; 73:952-964. [PMID: 32504662 DOI: 10.1016/j.jhep.2020.05.042] [Citation(s) in RCA: 106] [Impact Index Per Article: 26.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/18/2020] [Revised: 05/21/2020] [Accepted: 05/25/2020] [Indexed: 12/12/2022]
Abstract
Occult hepatitis B infection (OBI) refers to a condition where replication-competent HBV DNA is present in the liver, with or without HBV DNA in the blood, in individuals with serum HBsAg negativity assessed by currently available assays. The episomal covalently closed circular DNA (cccDNA) in OBI is in a low replicative state. Viral gene expression is mediated by epigenetic control of HBV transcription, including the HBV CpG island methylation pathway and post-translational modification of cccDNA-bound histone, with a different pattern from patients with chronic HBV infection. The prevalence of OBI varies tremendously across patient populations owing to numerous factors, such as geographic location, assay characteristics, host immune response, coinfection with other viruses, and vaccination status. Apart from the risk of viral reactivation upon immunosuppression and the risk of transmission of HBV, OBI has been implicated in hepatocellular carcinoma (HCC) development in patients with chronic HCV infection, those with cryptogenic or known liver disease, and in patients with HBsAg seroclearance after chronic HBV infection. An increasing number of prospective studies and meta-analyses have reported a higher incidence of HCC in patients with HCV and OBI, as well as more advanced tumour histological grades and earlier age of HCC diagnosis, compared with patients without OBI. The proposed pathogenetic mechanisms of OBI-related HCC include the influence of HBV DNA integration on the hepatocyte cell cycle, the production of pro-oncogenic proteins (HBx protein and mutated surface proteins), and persistent low-grade necroinflammation (contributing to the development of fibrosis and cirrhosis). There remain uncertainties about exactly how, and in what order, these mechanisms drive the development of tumours in patients with OBI.
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90
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Alexopoulou A, Vasilieva L, Karayiannis P. New Approaches to the Treatment of Chronic Hepatitis B. J Clin Med 2020; 9:jcm9103187. [PMID: 33019573 PMCID: PMC7601587 DOI: 10.3390/jcm9103187] [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: 09/03/2020] [Revised: 09/26/2020] [Accepted: 09/28/2020] [Indexed: 02/07/2023] Open
Abstract
The currently recommended treatment for chronic hepatitis B virus (HBV) infection achieves only viral suppression whilst on therapy, but rarely hepatitis B surface antigen (HBsAg) loss. The ultimate therapeutic endpoint is the combination of HBsAg loss, inhibition of new hepatocyte infection, elimination of the covalently closed circular DNA (cccDNA) pool, and restoration of immune function in order to achieve virus control. This review concentrates on new antiviral drugs that target different stages of the HBV life cycle (direct acting antivirals) and others that enhance both innate and adaptive immunity against HBV (immunotherapy). Drugs that block HBV hepatocyte entry, compounds that silence or deplete the cccDNA pool, others that affect core assembly, agents that degrade RNase-H, interfering RNA molecules, and nucleic acid polymers are likely interventions in the viral life cycle. In the immunotherapy category, molecules that activate the innate immune response such as Toll-like-receptors, Retinoic acid Inducible Gene-1 (RIG-1) and stimulator of interferon genes (STING) agonists or checkpoint inhibitors, and modulation of the adaptive immunity by therapeutic vaccines, vector-based vaccines, or adoptive transfer of genetically-engineered T cells aim towards the restoration of T cell function. Future therapeutic trends would likely be a combination of one or more of the aforementioned drugs that target the viral life cycle and at least one immunomodulator.
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Affiliation(s)
- Alexandra Alexopoulou
- Department of Medicine, Medical School, National & Kapodistrian University of Athens, Hippokration General Hospital, 11527 Athens, Greece;
- Correspondence: ; Tel.: +30-2132-088-178; Fax: +30-2107-706-871
| | - Larisa Vasilieva
- Department of Medicine, Medical School, National & Kapodistrian University of Athens, Hippokration General Hospital, 11527 Athens, Greece;
| | - Peter Karayiannis
- Department of Basic and Clinical Sciences, Medical School, University of Nicosia, Engomi, CY-1700 Nicosia, Cyprus;
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91
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Yuan Y, Yuan H, Yang G, Yun H, Zhao M, Liu Z, Zhao L, Geng Y, Liu L, Wang J, Zhang H, Wang Y, Zhang XD. IFN-α confers epigenetic regulation of HBV cccDNA minichromosome by modulating GCN5-mediated succinylation of histone H3K79 to clear HBV cccDNA. Clin Epigenetics 2020; 12:135. [PMID: 32894195 PMCID: PMC7487718 DOI: 10.1186/s13148-020-00928-z] [Citation(s) in RCA: 36] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2019] [Accepted: 08/26/2020] [Indexed: 02/06/2023] Open
Abstract
Background Hepatitis B virus covalently closed circular DNA (HBV cccDNA) is assembled by histones and non-histones into a chromatin-like cccDNA minichromosome in the nucleus. The cellular histone acetyltransferase GCN5, displaying succinyltransferase activity, is recruited onto cccDNA to modulate HBV transcription in cells. Clinically, IFN-α is able to repress cccDNA. However, the underlying mechanism of IFN-α in the depression of cccDNA mediated by GCN5 is poorly understood. Here, we explored the effect of IFN-α on GCN5-mediated succinylation in the epigenetic regulation of HBV cccDNA minichromosome. Results Succinylation modification of the cccDNA minichromosome has been observed in HBV-infected human liver-chimeric mice and HBV-expressing cell lines. Moreover, histone H3K79 succinylation by GCN5 was identified in the system. Interestingly, the mutant of histone H3K79 efficiently blocked the replication of HBV, and interference with GCN5 resulted in decreased levels of HBV DNA, HBsAg, and HBeAg in the supernatant from de novo HBV-infected HepaRG cells. Consistently, the levels of histone H3K79 succinylation were significantly elevated in the livers of HBV-infected human liver-chimeric mice. The knockdown or overexpression of GCN5 or the mutant of GCN5 could affect the binding of GCN5 to cccDNA or H3K79 succinylation, leading to a change in cccDNA transcription activity. In addition, Southern blot analysis validated that siGCN5 decreased the levels of cccDNA in the cells, suggesting that GCN5-mediated succinylation of histone H3K79 contributes to the epigenetic regulation of cccDNA minichromosome. Strikingly, IFN-α effectively depressed histone H3K79 succinylation in HBV cccDNA minichromosome in de novo HepG2-NTCP and HBV-infected HepaRG cells. Conclusions IFN-α epigenetically regulates the HBV cccDNA minichromosome by modulating GCN5-mediated succinylation of histone H3K79 to clear HBV cccDNA. Our findings provide new insights into the mechanism by which IFN-α modulate the epigenetic regulation of HBV cccDNA minichromosome.
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Affiliation(s)
- Ying Yuan
- Nankai University, 94 Weijin Road, Tianjin, 300071, People's Republic of China
| | - Hongfeng Yuan
- Nankai University, 94 Weijin Road, Tianjin, 300071, People's Republic of China
| | - Guang Yang
- Nankai University, 94 Weijin Road, Tianjin, 300071, People's Republic of China
| | - Haolin Yun
- Nankai University, 94 Weijin Road, Tianjin, 300071, People's Republic of China
| | - Man Zhao
- Nankai University, 94 Weijin Road, Tianjin, 300071, People's Republic of China
| | - Zixian Liu
- Nankai University, 94 Weijin Road, Tianjin, 300071, People's Republic of China
| | - Lina Zhao
- Nankai University, 94 Weijin Road, Tianjin, 300071, People's Republic of China
| | - Yu Geng
- Nankai University, 94 Weijin Road, Tianjin, 300071, People's Republic of China
| | - Lei Liu
- Nankai University, 94 Weijin Road, Tianjin, 300071, People's Republic of China
| | - Jiapei Wang
- Nankai University, 94 Weijin Road, Tianjin, 300071, People's Republic of China
| | - Huihui Zhang
- Nankai University, 94 Weijin Road, Tianjin, 300071, People's Republic of China
| | - Yufei Wang
- Nankai University, 94 Weijin Road, Tianjin, 300071, People's Republic of China
| | - Xiao-Dong Zhang
- Nankai University, 94 Weijin Road, Tianjin, 300071, People's Republic of China.
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Ligat G, Goto K, Verrier E, Baumert TF. Targeting Viral cccDNA for Cure of Chronic Hepatitis B. CURRENT HEPATOLOGY REPORTS 2020; 19:235-244. [PMID: 36034467 PMCID: PMC7613435 DOI: 10.1007/s11901-020-00534-w] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Purpose of Review Chronic hepatitis B (CHB), caused by hepatitis B virus (HBV), is a major cause of advanced liver disease and hepatocellular carcinoma (HCC) worldwide. HBV replication is characterized by the synthesis of covalently closed circular (ccc) DNA which is not targeted by antiviral nucleos(t)ide analogues (NUCs) the key modality of standard of care. While HBV replication is successfully suppressed in treated patients, they remain at risk for developing HCC. While functional cure, characterized by loss of HBsAg, is the first goal of novel antiviral therapies, curative treatments eliminating cccDNA remain the ultimate goal. This review summarizes recent advances in the discovery and development of novel therapeutic strategies and their impact on cccDNA biology. Recent Findings Within the last decade, substantial progress has been made in the understanding of cccDNA biology including the discovery of host dependency factors, epigenetic regulation of cccDNA transcription and immune-mediated degradation. Several approaches targeting cccDNA either in a direct or indirect manner are currently at the stage of discovery, preclinical or early clinical development. Examples include genome-editing approaches, strategies targeting host dependency factors or epigenetic gene regulation, nucleocapsid modulators and immune-mediated degradation. Summary While direct-targeting cccDNA strategies are still largely at the preclinical stage of development, capsid assembly modulators and immune-based approaches have reached the clinical phase. Clinical trials are ongoing to assess their efficacy and safety in patients including their impact on viral cccDNA. Combination therapies provide additional opportunities to overcome current limitations of individual approaches.
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Affiliation(s)
- Gaëtan Ligat
- Université de Strasbourg, 67000 Strasbourg, France
- Institut de Recherche sur les Maladies Virales et Hépatiques, Inserm U1110, 3 Rue Koeberlé, 67000 Strasbourg, France
| | - Kaku Goto
- Université de Strasbourg, 67000 Strasbourg, France
- Institut de Recherche sur les Maladies Virales et Hépatiques, Inserm U1110, 3 Rue Koeberlé, 67000 Strasbourg, France
| | - Eloi Verrier
- Université de Strasbourg, 67000 Strasbourg, France
- Institut de Recherche sur les Maladies Virales et Hépatiques, Inserm U1110, 3 Rue Koeberlé, 67000 Strasbourg, France
| | - Thomas F. Baumert
- Université de Strasbourg, 67000 Strasbourg, France
- Institut de Recherche sur les Maladies Virales et Hépatiques, Inserm U1110, 3 Rue Koeberlé, 67000 Strasbourg, France
- Institut Hospitalo-Universitaire, Pôle Hépato-digestif, Nouvel Hôpital Civil, 67000 Strasbourg, France
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93
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Abstract
Hepatitis B virus (HBV) infection causes chronic hepatitis and has long term complications. Individuals ever infected with HBV are at risk of viral reactivation under certain circumstances. This review summarizes studies on HBV persistence and reactivation with a focus on the definitions and mechanisms. Emphasis is placed on the interplay between HBV replication and host immunity as this interplay determines the patterns of persistence following viral acquisition. Chronic infections exhibit as overt persistence when a defective immune response fails to control the viral replication. The HBV genome persists despite an immune response in the form of covalently closed circular DNA (cccDNA) and integrated DNA, rendering an occult state of viral persistence in individuals whose infection appears to have been resolved. We have described HBV reactivation that occurs because of changes in the virus or the immune system. This review aims to raise the awareness of HBV reactivation and to understand how HBV persists, and discusses the risks of HBV reactivation in a variety of clinical settings.
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Affiliation(s)
- Yu Shi
- The State Key Laboratory for Diagnosis and Treatment of Infectious Diseases, The First Affiliated Hospital of School of Medicine, Zhejiang University, Hangzhou, China
- Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, Hangzhou, China
- National Clinical Research Center for Infectious Diseases, China
| | - Min Zheng
- The State Key Laboratory for Diagnosis and Treatment of Infectious Diseases, The First Affiliated Hospital of School of Medicine, Zhejiang University, Hangzhou, China
- Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, Hangzhou, China
- National Clinical Research Center for Infectious Diseases, China
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94
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Viswanathan U, Mani N, Hu Z, Ban H, Du Y, Hu J, Chang J, Guo JT. Targeting the multifunctional HBV core protein as a potential cure for chronic hepatitis B. Antiviral Res 2020; 182:104917. [PMID: 32818519 DOI: 10.1016/j.antiviral.2020.104917] [Citation(s) in RCA: 60] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2020] [Revised: 08/08/2020] [Accepted: 08/10/2020] [Indexed: 12/14/2022]
Abstract
The core (capsid) protein of hepatitis B virus (HBV) is the building block of nucleocapsids where viral DNA reverse transcriptional replication takes place and mediates virus-host cell interaction important for the persistence of HBV infection. The pleiotropic role of core protein (Cp) in HBV replication makes it an attractive target for antiviral therapies of chronic hepatitis B, a disease that affects more than 257 million people worldwide without a cure. Recent clinical studies indicate that core protein allosteric modulators (CpAMs) have a great promise as a key component of hepatitis B curative therapies. Particularly, it has been demonstrated that modulation of Cp dimer-dimer interactions by several chemical series of CpAMs not only inhibit nucleocapsid assembly and viral DNA replication, but also induce the disassembly of double-stranded DNA-containing nucleocapsids to prevent the synthesis of cccDNA. Moreover, the different chemotypes of CpAMs modulate Cp assembly by interaction with distinct amino acid residues at the HAP pocket between Cp dimer-dimer interfaces, which results in the assembly of Cp dimers into either non-capsid Cp polymers (type I CpAMs) or empty capsids with distinct physical property (type II CpAMs). The different CpAMs also differentially modulate Cp metabolism and subcellular distribution, which may impact cccDNA metabolism and host antiviral immune responses, the critical factors for the cure of chronic HBV infection. This review article highlights the recent research progress on the structure and function of core protein in HBV replication cycle, the mode of action of CpAMs, as well as the current status and perspectives on the discovery and development of core protein-targeting antivirals. This article forms part of a symposium in Antiviral Research on "Wide-ranging immune and direct-acting antiviral approaches to curing HBV and HDV infections."
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Affiliation(s)
- Usha Viswanathan
- Baruch S. Blumberg Institute, 3805 Old Easton Road, Doylestown, PA, 18902, USA
| | - Nagraj Mani
- Arbutus Biopharma Inc., 701 Veterans Circle, Warminster, PA, 18974, USA
| | - Zhanying Hu
- Baruch S. Blumberg Institute, 3805 Old Easton Road, Doylestown, PA, 18902, USA
| | - Haiqun Ban
- Baruch S. Blumberg Institute, 3805 Old Easton Road, Doylestown, PA, 18902, USA
| | - Yanming Du
- Baruch S. Blumberg Institute, 3805 Old Easton Road, Doylestown, PA, 18902, USA
| | - Jin Hu
- Baruch S. Blumberg Institute, 3805 Old Easton Road, Doylestown, PA, 18902, USA
| | - Jinhong Chang
- Baruch S. Blumberg Institute, 3805 Old Easton Road, Doylestown, PA, 18902, USA
| | - Ju-Tao Guo
- Baruch S. Blumberg Institute, 3805 Old Easton Road, Doylestown, PA, 18902, USA.
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95
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Xia Y, Guo H. Hepatitis B virus cccDNA: Formation, regulation and therapeutic potential. Antiviral Res 2020; 180:104824. [PMID: 32450266 PMCID: PMC7387223 DOI: 10.1016/j.antiviral.2020.104824] [Citation(s) in RCA: 89] [Impact Index Per Article: 22.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/29/2020] [Revised: 05/03/2020] [Accepted: 05/18/2020] [Indexed: 02/06/2023]
Abstract
Hepatitis B virus (HBV) infection remains a major public health concern worldwide with about 257 million individuals chronically infected. Current therapies can effectively control HBV replication and slow down disease progress, but cannot cure HBV infection. Upon infection, HBV establishes a pool of covalently closed circular DNA (cccDNA) in the nucleus of infected hepatocytes. The cccDNA exists as a minichromosome and resists to antivirals, thus a therapeutic eradication of cccDNA from the infected cells remains unattainable. In this review, we summarize the state of knowledge on the mechanisms underlying cccDNA formation and regulation, and discuss the possible strategies that may contribute to the eradication of HBV through targeting cccDNA.
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Affiliation(s)
- Yuchen Xia
- State Key Laboratory of Virology and Hubei Province Key Laboratory of Allergy and Immunology, School of Basic Medical Sciences, Wuhan University, Wuhan, China.
| | - Haitao Guo
- UPMC Hillman Cancer Center, Department of Microbiology and Molecular Genetics, University of Pittsburgh, Pittsburgh, PA, USA.
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96
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Muraleedharan A, Bupesh G. A short note on HBV infection. Bioinformation 2020; 16:505-508. [PMID: 32994674 PMCID: PMC7505248 DOI: 10.6026/97320630016505] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/01/2020] [Revised: 05/25/2020] [Accepted: 05/30/2020] [Indexed: 11/23/2022] Open
Abstract
HBV-related liver sickness or hepatocellular carcinoma is common worldwide. Therefore, it is of interest to document the current trends in hepatitis prevention, diagnosis, treatment and care.
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Affiliation(s)
- Aiswarya Muraleedharan
- 1Research and Development Wing, Central Research Laboratory, Sree Balaji Medical College and Hospital (SBMCH), BIHER, Chrompet, Chennai - 600044, India
| | - Giridharan Bupesh
- 1Research and Development Wing, Central Research Laboratory, Sree Balaji Medical College and Hospital (SBMCH), BIHER, Chrompet, Chennai - 600044, India
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97
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An Alternatively Spliced Sirtuin 2 Isoform 5 Inhibits Hepatitis B Virus Replication from cccDNA by Repressing Epigenetic Modifications Made by Histone Lysine Methyltransferases. J Virol 2020; 94:JVI.00926-20. [PMID: 32493816 DOI: 10.1128/jvi.00926-20] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2020] [Accepted: 05/12/2020] [Indexed: 02/07/2023] Open
Abstract
Sirtuin 2 (Sirt2), an NAD+-dependent protein deacetylase, deacetylates tubulin, AKT, and other proteins. Previously, we showed that Sirt2 isoform 1 (Sirt2.1) increased replication of hepatitis B virus (HBV). Here, we show that HBV replication upregulates the expression of Sirt2 primary and alternatively spliced transcripts and their respective isoforms, 1, 2, and 5. Since Sirt2 isoform 5 (Sirt2.5) is a catalytically inactive nuclear protein with a spliced-out nuclear export signal (NES), we speculated that its different localization affects its activity. The overexpression of Sirt2.5 reduced expression of HBV mRNAs, replicative intermediate DNAs, and covalently closed circular DNA (cccDNA), an activity opposite that of Sirt2.1 and Sirt2.2. Unlike the Sirt2.1-AKT interaction, the Sirt2.5-AKT interaction was weakened by HBV replication. Unlike Sirt2.1, Sirt2.5 activated the AKT/GSK-3β/β-catenin signaling pathway very weakly and independently of HBV replication. When the NES and an N-terminal truncated catalytic domain were added to the Sirt2.5 construct, it localized in the cytoplasm and increased HBV replication (like Sirt2.1 and Sirt2.2). Chromatin immunoprecipitation assays revealed that more Sirt2.5 was recruited to cccDNA than Sirt2.1. The recruitment of histone lysine methyltransferases (HKMTs), such as SETDB1, SUV39H1, EZH2, and PR-Set7, and their respective transcriptional repressive markers, H3K9me3, H3K27me3, and H4K20me1, to cccDNA also increased in Sirt2.5-overexpressing cells. Among these, the Sirt2.5-PR-Set7 and -SETDB1 interactions increased upon HBV replication. These results demonstrate that Sirt2.5 reduces cccDNA levels and viral transcription through epigenetic modification of cccDNA via direct and/or indirect association with HKMTs, thereby exhibiting anti-HBV activity.IMPORTANCE Sirt2, a predominant cytoplasmic α-tubulin deacetylase, promotes the growth of hepatocellular carcinoma; indeed, HBV replication increases Sirt2 expression, and overexpression of Sirt2 is associated with hepatic fibrosis and epithelial-to-mesenchymal transition. Increased amounts of Sirt2 isoforms 1, 2, and 5 upon HBV replication might further upregulate HBV replication, leading to a vicious cycle of virus replication/disease progression. However, we show here that catalytically inactive nuclear Sirt2.5 antagonizes the effects of Sirt2.1 and Sirt2.2 on HBV replication, thereby inhibiting cccDNA level, transcription of cccDNA, and subsequent synthesis of replicative intermediate DNA. More Sirt2.5 was recruited to cccDNA than Sirt2.1, thereby increasing epigenetic modification by depositing transcriptional repressive markers, possibly through direct and/or indirect association with histone lysine methyltransferases, such as SETDB1, SUV39H1, EZH2, and/or PR-Set7, which represses HBV transcription. Thus, Sirt2.5 might provide a functional cure for HBV by silencing the transcription of HBV.
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98
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Wang Z, Wang W, Wang L. Epigenetic regulation of covalently closed circular DNA minichromosome in hepatitis B virus infection. BIOPHYSICS REPORTS 2020. [DOI: 10.1007/s41048-020-00112-z] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
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99
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Phosphorylation of the Arginine-Rich C-Terminal Domains of the Hepatitis B Virus (HBV) Core Protein as a Fine Regulator of the Interaction between HBc and Nucleic Acid. Viruses 2020; 12:v12070738. [PMID: 32650547 PMCID: PMC7412469 DOI: 10.3390/v12070738] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2020] [Revised: 07/02/2020] [Accepted: 07/03/2020] [Indexed: 02/08/2023] Open
Abstract
The morphogenesis of Hepatitis B Virus (HBV) viral particles is nucleated by the oligomerization of HBc protein molecules, resulting in the formation of an icosahedral capsid shell containing the replication-competent nucleoprotein complex made of the viral polymerase and the pre-genomic RNA (pgRNA). HBc is a phospho-protein containing two distinct domains acting together throughout the viral replication cycle. The N-terminal domain, (residues 1–140), shown to self-assemble, is linked by a short flexible domain to the basic C-terminal domain (residues 150–183) that interacts with nucleic acids (NAs). In addition, the C-terminal domain contains a series of phospho-acceptor residues that undergo partial phosphorylation and de-phosphorylation during virus replication. This highly dynamic process governs the homeostatic charge that is essential for capsid stability, pgRNA packaging and to expose the C-terminal domain at the surface of the particles for cell trafficking. In this review, we discuss the roles of the N-terminal and C-terminal domains of HBc protein during HBV morphogenesis, focusing on how the C-terminal domain phosphorylation dynamics regulate its interaction with nucleic acids throughout the assembly and maturation of HBV particles.
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100
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Yuen M, Schiefke I, Yoon J, Ahn SH, Heo J, Kim JH, Lik Yuen Chan H, Yoon KT, Klinker H, Manns M, Petersen J, Schluep T, Hamilton J, Given BD, Ferrari C, Lai C, Locarnini SA, Gish RG. RNA Interference Therapy With ARC-520 Results in Prolonged Hepatitis B Surface Antigen Response in Patients With Chronic Hepatitis B Infection. Hepatology 2020; 72:19-31. [PMID: 31654573 PMCID: PMC7496196 DOI: 10.1002/hep.31008] [Citation(s) in RCA: 75] [Impact Index Per Article: 18.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/12/2019] [Accepted: 10/23/2019] [Indexed: 12/12/2022]
Abstract
BACKGROUND AND AIMS ARC-520, the first an RNA interference (RNAi) therapeutic, was designed to reduce all RNA transcripts derived from covalently closed circular DNA, leading to a reduction in viral antigens and hepatitis B virus (HBV) DNA. APPROACH AND RESULTS We aimed to evaluate the depth of hepatitis B surface antigen (HBsAg) decline in response to multiple doses of ARC-520 compared to placebo (PBO) in two randomized, multicenter studies in nucleoside/nucleotide analogue reverse-transcriptase inhibitor (NUC)-experienced patients with hepatitis B early antigen (HBeAg)-negative (E-neg) or HBeAg-positive (E-pos) disease. A total of 58 E-neg and 32 E-pos patients were enrolled and received four monthly doses of PBO (n = 20 E-neg, 11 E-pos), 1 mg/kg ARC-520 (n = 17 E-neg, 10 E-pos), or 2 mg/kg ARC-520 (n = 21 E-neg, 11 E-pos) concomitantly with NUC. HBsAg change from baseline to 30 days after the last ARC-520 dose were compared to PBO. Both E-neg and E-pos high-dose groups significantly reduced HBsAg compared to PBO, with mean reductions of 0.38 and 0.54 log IU/mL, respectively. HBsAg reductions persisted for approximately 85 days and >85 days after the last dose in E-neg and E-pos patients, respectively. The low-dose groups did not reach statistical significance in either study. E-pos patients showed a dose-dependent reduction in HBeAg from baseline. Mean maximum reduction was 0.23 and 0.69 log Paul Ehrlich IUs/mL in the low-dose and high dose ARC-520 groups respectively. ARC-520 was well tolerated, with only two serious adverse events of pyrexia possibly related to study drug observed. CONCLUSIONS ARC-520 was active in both E-neg and E-pos, NUC-experienced HBV patients; but absolute HBsAg reductions were moderate, possibly due to expression of HBsAg from integrated HBV DNA, indicating the need for RNAi therapeutics that can target viral transcripts regardless of origin.
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Affiliation(s)
- Man‐Fung Yuen
- Queen Mary HospitalThe University of Hong KongHong KongChina
| | | | - Jung‐Hwan Yoon
- Seoul National University HospitalSeoulRepublic of Korea
| | - Sang Hoon Ahn
- Yonsei University College of MedicineSeoulRepublic of Korea
| | - Jeong Heo
- Pusan National University and Medical Research InstituteBusanRepublic of Korea
| | - Ju Hyun Kim
- Gachon University Gil HospitalIncheonRepublic of Korea
| | | | - Ki Tae Yoon
- Pusan National University Yangsan HospitalYangsan‐siRepublic of Korea
| | | | | | - Joerg Petersen
- IFI Institute at Asklepios Klinik St. GeorgHamburgGermany
| | | | | | | | - Carlo Ferrari
- Unit of Infectious Diseases and HepatologyUniversity of ParmaParmaItaly
| | - Ching‐Lung Lai
- Queen Mary HospitalThe University of Hong KongHong KongChina
| | | | - Robert G. Gish
- Division of Gastroenterology and HepatologyDepartment of MedicineStanford University Medical CenterStanfordCA
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