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Jeong Y, Han J, Jang KL. Reactive Oxygen Species Induction by Hepatitis B Virus: Implications for Viral Replication in p53-Positive Human Hepatoma Cells. Int J Mol Sci 2024; 25:6606. [PMID: 38928309 PMCID: PMC11204012 DOI: 10.3390/ijms25126606] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2024] [Revised: 06/03/2024] [Accepted: 06/11/2024] [Indexed: 06/28/2024] Open
Abstract
Hepatitis B virus (HBV) infects approximately 300 million people worldwide, causing chronic infections. The HBV X protein (HBx) is crucial for viral replication and induces reactive oxygen species (ROS), leading to cellular damage. This study explores the relationship between HBx-induced ROS, p53 activation, and HBV replication. Using HepG2 and Hep3B cell lines that express the HBV receptor NTCP, we compared ROS generation and HBV replication relative to p53 status. Results indicated that HBV infection significantly increased ROS levels in p53-positive HepG2-NTCP cells compared to p53-deficient Hep3B-NTCP cells. Knockdown of p53 reduced ROS levels and enhanced HBV replication in HepG2-NTCP cells, whereas p53 overexpression increased ROS and inhibited HBV replication in Hep3B-NTCP cells. The ROS scavenger N-acetyl-L-cysteine (NAC) reversed these effects. The study also found that ROS-induced degradation of the HBx is mediated by the E3 ligase Siah-1, which is activated by p53. Mutations in p53 or inhibition of its transcriptional activity prevented ROS-mediated HBx degradation and HBV inhibition. These findings reveal a p53-dependent negative feedback loop where HBx-induced ROS increases p53 levels, leading to Siah-1-mediated HBx degradation and HBV replication inhibition. This study offers insights into the molecular mechanisms of HBV replication and identifies potential therapeutic targets involving ROS and p53 pathways.
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Affiliation(s)
- Yuna Jeong
- Department of Integrated Biological Science, The Graduate School, Pusan National University, Busan 46241, Republic of Korea; (Y.J.); (J.H.)
| | - Jiwoo Han
- Department of Integrated Biological Science, The Graduate School, Pusan National University, Busan 46241, Republic of Korea; (Y.J.); (J.H.)
| | - Kyung Lib Jang
- Department of Integrated Biological Science, The Graduate School, Pusan National University, Busan 46241, Republic of Korea; (Y.J.); (J.H.)
- Department of Microbiology, College of Natural Science, Pusan National University, Busan 46241, Republic of Korea
- Microbiological Resource Research Institute, Pusan National University, Busan 46241, Republic of Korea
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2
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Han J, Jang KL. All-trans retinoic acid downregulates HBx levels via E6-associated protein-mediated proteasomal degradation to suppress hepatitis B virus replication. PLoS One 2024; 19:e0305350. [PMID: 38861553 PMCID: PMC11166335 DOI: 10.1371/journal.pone.0305350] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2024] [Accepted: 05/28/2024] [Indexed: 06/13/2024] Open
Abstract
All-trans retinoic acid (ATRA), recognized as the principal and most biologically potent metabolite of vitamin A, has been identified for its inhibitory effects on hepatitis B virus (HBV) replication. Nevertheless, the underlying mechanism remains elusive. The present study reveals that ATRA induces E6-associated protein (E6AP)-mediated proteasomal degradation of HBx to suppress HBV replication in human hepatoma cells in a p53-dependent pathway. For this effect, ATRA induced promoter hypomethylation of E6AP in the presence of HBx, which resulted in the upregulation of E6AP levels in HepG2 but not in Hep3B cells, emphasizing the p53-dependent nature of this effect. As a consequence, ATRA augmented the interaction between E6AP and HBx, resulting in substantial ubiquitination of HBx and consequent reduction in HBx protein levels in both the HBx overexpression system and the in vitro HBV replication model. Additionally, the knockdown of E6AP under ATRA treatment reduced the interaction between HBx and E6AP and decreased the ubiquitin-dependent proteasomal degradation of HBx, which prompted a recovery of HBV replication in the presence of ATRA, as confirmed by increased levels of intracellular HBV proteins and secreted HBV levels. This study not only contributes to the understanding of the complex interactions between ATRA, p53, E6AP, and HBx but also provides an academic basis for the clinical employment of ATRA in the treatment of HBV infection.
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Affiliation(s)
- Jiwoo Han
- Department of Integrated Biological Science, The Graduate School, Pusan National University, Busan, Republic of Korea
| | - Kyung Lib Jang
- Department of Integrated Biological Science, The Graduate School, Pusan National University, Busan, Republic of Korea
- Department of Microbiology, College of Natural Science, Pusan National University, Busan, Republic of Korea
- Microbiological Resource Research Institute, Pusan National University, Busan, Republic of Korea
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3
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Wang J, Yuan X, Wang Y, Zhang Y, Han M, Lu H, Liu S, Zhang Y, Ge F, Liu Y, Cheng J. PreS1BP mediates inhibition of Hepatitis B virus replication by promoting HBx protein degradation. Virus Res 2024; 341:199326. [PMID: 38253259 PMCID: PMC10846407 DOI: 10.1016/j.virusres.2024.199326] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2023] [Revised: 01/07/2024] [Accepted: 01/18/2024] [Indexed: 01/24/2024]
Abstract
BACKGROUND PreS1-binding protein (PreS1BP), recognized as a nucleolar protein and tumor suppressor, influences the replication of various viruses, including vesicular stomatitis virus (VSV) and herpes simplex virus type 1 (HSV-1). Its role in hepatitis B virus (HBV) replication and the underlying mechanisms, however, remain elusive. METHODS We investigated PreS1BP expression levels in an HBV-replicating cell and animal model and analyzed the impact of its overexpression on viral replication metrics. HBV DNA, covalently closed circular DNA (cccDNA), hepatitis B surface antigen (HBsAg), hepatitis B core antigen (HBcAg), and HBV RNA levels were assessed in HBV-expressing stable cell lines under varying PreS1BP conditions. Furthermore, co-immunoprecipitation and ubiquitination assays were used to detect PreS1BP- hepatitis B virus X protein (HBx) interactions and HBx stability modulated by PreS1BP. RESULTS Our study revealed a marked decrease in PreS1BP expression in the presence of active HBV replication. Functional assays showed that PreS1BP overexpression significantly inhibited HBV replication and transcription, evidenced by the reduction in HBV DNA, cccDNA, HBsAg, HBcAg, and HBV RNA levels. At the molecular level, PreS1BP facilitated the degradation of HBx in a dose-dependent fashion, whereas siRNA-mediated knockdown of PreS1BP led to an increase in HBx levels. Subsequent investigations uncovered that PreS1BP accelerated HBx protein degradation via K63-linked ubiquitination in a ubiquitin-proteasome system-dependent manner. Co-immunoprecipitation assays further established that PreS1BP enhances the recruitment of the proteasome 20S subunit alpha 3 (PSMA3) for interaction with HBx, thereby fostering its degradation. CONCLUSIONS These findings unveil a previously unidentified mechanism wherein PreS1BP mediates HBx protein degradation through the ubiquitin-proteasome system, consequentially inhibiting HBV replication. This insight positions PreS1BP as a promising therapeutic target for future HBV interventions. Further studies are warranted to explore the clinical applicability of modulating PreS1BP in HBV therapy.
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Affiliation(s)
- Jun Wang
- Peking University Ditan Teaching Hospital, Beijing 100015, China; Beijing Key Laboratory of Emerging Infectious Diseases, Institute of Infectious Diseases, Beijing Ditan Hospital, Capital Medical University, Beijing 100015, China
| | - Xiaoxue Yuan
- Beijing Key Laboratory of Emerging Infectious Diseases, Institute of Infectious Diseases, Beijing Ditan Hospital, Capital Medical University, Beijing 100015, China; The Division of Liver Diseases, Beijing Ditan Hospital, Capital Medical University, Beijing 100015, China
| | - Yun Wang
- The Division of Liver Diseases, Beijing Ditan Hospital, Capital Medical University, Beijing 100015, China
| | - Yu Zhang
- The Division of Liver Diseases, Beijing Ditan Hospital, Capital Medical University, Beijing 100015, China
| | - Ming Han
- Beijing Key Laboratory of Emerging Infectious Diseases, Institute of Infectious Diseases, Beijing Ditan Hospital, Capital Medical University, Beijing 100015, China; The Division of Liver Diseases, Beijing Ditan Hospital, Capital Medical University, Beijing 100015, China
| | - Hongping Lu
- Hebei Utu Pharmaceutical Company Ltd, Shijiazhuang, Hebei Province 052165, China
| | - Shunai Liu
- Beijing Key Laboratory of Emerging Infectious Diseases, Institute of Infectious Diseases, Beijing Ditan Hospital, Capital Medical University, Beijing 100015, China; The Division of Liver Diseases, Beijing Ditan Hospital, Capital Medical University, Beijing 100015, China
| | - Yang Zhang
- Beijing Key Laboratory of Emerging Infectious Diseases, Institute of Infectious Diseases, Beijing Ditan Hospital, Capital Medical University, Beijing 100015, China
| | - Feilin Ge
- Department of Chinese Medicine, the First Affiliated Hospital of Zhengzhou University, Zhengzhou 450052, China
| | - Yan Liu
- Department of Infectious Diseases, The Fifth Medical Center of Chinese PLA General Hospital, Beijing 100039, China.
| | - Jun Cheng
- Peking University Ditan Teaching Hospital, Beijing 100015, China; Hebei Utu Pharmaceutical Company Ltd, Shijiazhuang, Hebei Province 052165, China.
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Saeed U, Piracha ZZ, Alrokayan S, Hussain T, Almajhdi FN, Waheed Y. Immunoinformatics and Evaluation of Peptide Vaccines Derived from Global Hepatitis B Viral HBx and HBc Proteins Critical for Covalently Closed Circular DNA Integrity. Microorganisms 2023; 11:2826. [PMID: 38137971 PMCID: PMC10745757 DOI: 10.3390/microorganisms11122826] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2023] [Revised: 11/07/2023] [Accepted: 11/17/2023] [Indexed: 12/24/2023] Open
Abstract
The Hepatitis B virus (HBV) HBx and HBc proteins play a crucial role in associating with covalently closed circular DNA (cccDNA), the primary factor contributing to intrahepatic viral persistence and a major obstacle in achieving a cure for HBV. The cccDNA serves as a reservoir for viral persistence. Targeting the viral HBc and HBx proteins' interaction with cccDNA could potentially limit HBV replication. In this study, we present epitopes identified from global consensus sequences of HBx and HBc proteins that have the potential to serve as targets for the development of effective vaccine candidates. Furthermore, conserved residues identified through this analysis can be utilized in designing novel, site-specific anti-HBV agents capable of targeting all major genotypes of HBV. Our approach involved designing global consensus sequences for HBx and HBc proteins, enabling the analysis of variable regions and highly conserved motifs. These identified motifs and regions offer potent sites for the development of peptide vaccines, the design of site-specific RNA interference, and the creation of anti-HBV inhibitors. The epitopes derived from global consensus sequences of HBx and HBc proteins emerge as promising targets for the development of effective vaccine candidates. Additionally, the conserved residues identified provide valuable insights for the development of innovative, site-specific anti-HBV agents capable of targeting all major genotypes of HBV from A to J.
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Affiliation(s)
- Umar Saeed
- Clinical and Biomedical Research Center (CBRC) and Multidisciplinary Laboratory (MDL), Foundation University Islamabad, Islamabad 44000, Pakistan;
- Department of Microbiology, Ajou University School of Medicine, Suwon 443-749, Republic of Korea;
| | - Zahra Zahid Piracha
- Department of Microbiology, Ajou University School of Medicine, Suwon 443-749, Republic of Korea;
- International Center of Medical Sciences Research (ICMSR), Islamabad 44000, Pakistan
| | - Salman Alrokayan
- Research Chair for Biomedical Application of Nanomaterials, Biochemistry Department, College of Sciences, King Saud University, Riyadh 11362, Saudi Arabia;
| | - Tajamul Hussain
- Research Chair for Biomedical Application of Nanomaterials, Biochemistry Department, College of Sciences, King Saud University, Riyadh 11362, Saudi Arabia;
- Center of Excellence in Biotechnology Research, College of Applied Medical Sciences, King Saud University, P.O. Box 10219, Riyadh 11451, Saudi Arabia
| | - Fahad N. Almajhdi
- Botany and Microbiology Department, College of Science, King Saud University, P.O. Box 2455, Riyadh 11451, Saudi Arabia;
| | - Yasir Waheed
- Office of Research, Innovation, and Commercialization, Shaheed Zulfiqar Ali Bhutto Medical University, Islamabad 44000, Pakistan;
- Gilbert and Rose-Marie Chagoury School of Medicine, Lebanese American University, Byblos 1401, Lebanon
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5
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Kong X, Liu Z, Zhang R, Xie F, Liang R, Zhang Y, Yu L, Yang W, Li X, Chen Q, Li B, Hong Y, Li M, Xia X, Gu L, Fu L, Li X, Shen Y, Wu T, Yu C, Li W. JMJD2D stabilises and cooperates with HBx protein to promote HBV transcription and replication. JHEP Rep 2023; 5:100849. [PMID: 37701334 PMCID: PMC10494471 DOI: 10.1016/j.jhepr.2023.100849] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/09/2023] [Revised: 06/16/2023] [Accepted: 07/01/2023] [Indexed: 09/14/2023] Open
Abstract
Background & Aims HBV infection is a global health burden. Covalently closed circular DNA (cccDNA) transcriptional regulation is a major cause of poor cure rates of chronic hepatitis B (CHB) infection. Herein, we evaluated whether targeting host factors to achieve functional silencing of cccDNA may represent a novel strategy for the treatment of HBV infection. Methods To evaluate the effects of Jumonji C domain-containing (JMJD2) protein subfamily JMJD2A-2D proteins on HBV replication, we used lentivirus-based RNA interference to suppress the expression of isoforms JMJD2A-2D in HBV-infected cells. JMJD2D-knockout mice were generated to obtain an HBV-injected model for in vivo experiments. Co-immunoprecipitation and ubiquitylation assays were used to detect JMJD2D-HBx interactions and HBx stability modulated by JMJD2D. Chromatin immunoprecipitation assays were performed to investigate JMJD2D-cccDNA and HBx-cccDNA interactions. Results Among the JMJD2 family members, JMJD2D was significantly upregulated in mouse livers and human hepatoma cells. Downregulation of JMJD2D inhibited cccDNA transcription and HBV replication. Molecularly, JMJD2D sustained HBx stability by suppressing the TRIM14-mediated ubiquitin-proteasome degradation pathway and acted as a key co-activator of HBx to augment HBV replication. The JMJD2D-targeting inhibitor, 5C-8-HQ, suppressed cccDNA transcription and HBV replication. Conclusion Our study clarified the mechanism by which JMJD2D regulates HBV transcription and replication and identified JMJD2D as a potential diagnostic biomarker and promising drug target against CHB, and HBV-associated hepatocarcinoma. Impact and implications HBV cccDNA is central to persistent infection and is a major obstacle to healing CHB. In this study, using cellular and animal HBV models, JMJD2D was found to stabilise and cooperate with HBx to augment HBV transcription and replication. This study reveals a potential novel translational target for intervention in the treatment of chronic hepatitis B infection.
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Affiliation(s)
- Xu Kong
- Cancer Research Center, School of Medicine, Xiamen University, Xiamen, China
- Department of Hepatobiliary Surgery, Xiang’an Hospital of Xiamen University, School of Medicine, Xiamen University, Xiamen, China
| | - Zuofeng Liu
- Cancer Research Center, School of Medicine, Xiamen University, Xiamen, China
- Department of Hepatology, Affiliated Hospital of Panzhihua University, Panzhihua, China
| | - Ruyi Zhang
- Cancer Research Center, School of Medicine, Xiamen University, Xiamen, China
- Department of Hepatobiliary Surgery, Xiang’an Hospital of Xiamen University, School of Medicine, Xiamen University, Xiamen, China
| | - Fu’an Xie
- Cancer Research Center, School of Medicine, Xiamen University, Xiamen, China
- Department of Hepatobiliary Surgery, Xiang’an Hospital of Xiamen University, School of Medicine, Xiamen University, Xiamen, China
| | - Rubing Liang
- Cancer Research Center, School of Medicine, Xiamen University, Xiamen, China
- Department of Hepatobiliary Surgery, Xiang’an Hospital of Xiamen University, School of Medicine, Xiamen University, Xiamen, China
| | - Yong Zhang
- State Key Laboratory of Cellular Stress Biology, Innovation Center for Cell Biology, School of Life Sciences, Xiamen University, Xiamen, China
| | - Lingling Yu
- Department of Cardiology, Xiang’an Hospital of Xiamen University, School of Medicine, Xiamen University, China
| | - Wensheng Yang
- Department of Pathology, Chenggong Hospital of Xiamen University, Xiamen, China
| | - Xi Li
- College of Arts and Sciences, Boston University, Boston, MA, USA
| | - Qiang Chen
- State Key Laboratory of Cellular Stress Biology, Innovation Center for Cell Biology, School of Life Sciences, Xiamen University, Xiamen, China
| | - Bei Li
- State Key Laboratory of Cellular Stress Biology, Innovation Center for Cell Biology, School of Life Sciences, Xiamen University, Xiamen, China
| | - Yilin Hong
- State Key Laboratory of Cellular Stress Biology, Innovation Center for Cell Biology, School of Life Sciences, Xiamen University, Xiamen, China
| | - Ming Li
- Cancer Research Center, School of Medicine, Xiamen University, Xiamen, China
- Department of Hepatobiliary Surgery, Xiang’an Hospital of Xiamen University, School of Medicine, Xiamen University, Xiamen, China
- Key Laboratory of Natural Medicine Research and Developing, Xiamen Medicine Research Institute, Xiamen, China
| | - Xiaogang Xia
- Department of Hepatobiliary Surgery, Xiang’an Hospital of Xiamen University, School of Medicine, Xiamen University, Xiamen, China
| | - Lingwei Gu
- Cancer Research Center, School of Medicine, Xiamen University, Xiamen, China
- Department of Management, Jiang Xia Blood Technology Co., Ltd., Shanghai, China
| | - Lijuan Fu
- Department of Infectious Diseases, Xiang’an Hospital of Xiamen University, School of Medicine, Xiamen University, Xiamen, China
| | - Xiaohua Li
- Department of Surgery, Affiliated Fuzhou First Hospital of Fujian Medical University, Fuzhou, China
| | - Ye Shen
- Department of Management, Jiang Xia Blood Technology Co., Ltd., Shanghai, China
| | - Ting Wu
- Cancer Research Center, School of Medicine, Xiamen University, Xiamen, China
| | - Chundong Yu
- State Key Laboratory of Cellular Stress Biology, Innovation Center for Cell Biology, School of Life Sciences, Xiamen University, Xiamen, China
| | - Wengang Li
- Cancer Research Center, School of Medicine, Xiamen University, Xiamen, China
- Department of Hepatobiliary Surgery, Xiang’an Hospital of Xiamen University, School of Medicine, Xiamen University, Xiamen, China
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Yoon H, Lee HK, Jang KL. Hydrogen Peroxide Inhibits Hepatitis B Virus Replication by Downregulating HBx Levels via Siah-1-Mediated Proteasomal Degradation in Human Hepatoma Cells. Int J Mol Sci 2023; 24:13354. [PMID: 37686160 PMCID: PMC10488175 DOI: 10.3390/ijms241713354] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2023] [Revised: 08/24/2023] [Accepted: 08/25/2023] [Indexed: 09/10/2023] Open
Abstract
The hepatitis B virus (HBV) is constantly exposed to significant oxidative stress characterized by elevated levels of reactive oxygen species (ROS), such as H2O2, during infection in hepatocytes of patients. In this study, we demonstrated that H2O2 inhibits HBV replication in a p53-dependent fashion in human hepatoma cell lines expressing sodium taurocholate cotransporting polypeptide. Interestingly, H2O2 failed to inhibit the replication of an HBV X protein (HBx)-null HBV mutant, but this defect was successfully complemented by ectopic expression of HBx. Additionally, H2O2 upregulated p53 levels, leading to increased expression of seven in absentia homolog 1 (Siah-1) levels. Siah-1, an E3 ligase, induced the ubiquitination-dependent proteasomal degradation of HBx. The inhibitory effect of H2O2 was nearly abolished not only by treatment with a representative antioxidant, N-acetyl-L-cysteine but also by knockdown of either p53 or Siah-1 using specific short hairpin RNA, confirming the role of p53 and Siah-1 in the inhibition of HBV replication by H2O2. The present study provides insights into the mechanism that regulates HBV replication under conditions of oxidative stress in patients.
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Affiliation(s)
- Hyunyoung Yoon
- Department of Integrated Biological Science, The Graduate School, Pusan National University, Busan 46241, Republic of Korea; (H.Y.); (H.-K.L.)
| | - Hye-Kyoung Lee
- Department of Integrated Biological Science, The Graduate School, Pusan National University, Busan 46241, Republic of Korea; (H.Y.); (H.-K.L.)
| | - Kyung Lib Jang
- Department of Integrated Biological Science, The Graduate School, Pusan National University, Busan 46241, Republic of Korea; (H.Y.); (H.-K.L.)
- Department of Microbiology, College of Natural Science, Pusan National University, Busan 46241, Republic of Korea
- Microbiological Resource Research Institute, Pusan National University, Busan 46241, Republic of Korea
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7
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Han J, Jang KL. All- trans Retinoic Acid Inhibits Hepatitis B Virus Replication by Downregulating HBx Levels via Siah-1-Mediated Proteasomal Degradation. Viruses 2023; 15:1456. [PMID: 37515144 PMCID: PMC10386411 DOI: 10.3390/v15071456] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2023] [Revised: 06/22/2023] [Accepted: 06/26/2023] [Indexed: 07/30/2023] Open
Abstract
All-trans retinoic acid (ATRA), the most biologically active metabolite of vitamin A, is known to abolish the potential of HBx to downregulate the levels of p14, p16, and p21 and to stimulate cell growth during hepatitis B virus (HBV) infection, contributing to its chemopreventive and therapeutic effects against HBV-associated hepatocellular carcinoma. Here, we demonstrated that ATRA antagonizes HBx to inhibit HBV replication. For this effect, ATRA individually or in combination with HBx upregulated p53 levels, resulting in upregulation of seven in absentia homolog 1 (Siah-1) levels. Siah-1, an E3 ligase, induces ubiquitination and proteasomal degradation of HBx in the presence of ATRA. The ability of ATRA to induce Siah-1-mediated HBx degradation and the subsequent inhibition of HBV replication was proven in an in vitro HBV replication model. The effects of ATRA became invalid when either p53 or Siah-1 was knocked down by a specific shRNA, providing direct evidence for the role of p53 and Siah-1 in the negative regulation of HBV replication by ATRA.
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Affiliation(s)
- Jiwoo Han
- Department of Integrated Biological Science, The Graduate School, Pusan National University, Busan 46241, Republic of Korea
| | - Kyung Lib Jang
- Department of Integrated Biological Science, The Graduate School, Pusan National University, Busan 46241, Republic of Korea
- Department of Microbiology, College of Natural Science, Pusan National University, Busan 46241, Republic of Korea
- Microbiological Resource Research Institute, Pusan National University, Busan 46241, Republic of Korea
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8
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Wang MD, Xiang H, Hong TY, Mierxiati A, Yan FH, Zhang L, Wang C. Integrated analysis of intratumoral biomarker and tumor-associated macrophage to improve the prognosis prediction in cancer patients. BMC Cancer 2023; 23:593. [PMID: 37370037 DOI: 10.1186/s12885-023-11027-6] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2022] [Accepted: 05/30/2023] [Indexed: 06/29/2023] Open
Abstract
BACKGROUND The lack of effective and accurate predictive indicators remains a major bottleneck for the improvement of the prognosis of patients with hepatitis B virus (HBV)-related hepatocellular carcinoma (HCC). Hepatitis B virus X (HBx) has been widely suggested as a critical pathogenic protein for HBV-driven liver carcinogenesis, while tumor-associated macrophage (TAM) infiltration is also closely related to the tumorigenesis and progression of HCC. However, few studies have determined whether combining HBx expression with TAM populations could increase the accuracy of prognostic prediction for HBV-related HCC. METHODS The study cohort enrolling 251 patients with HBV-related HCC was randomly split into a training and a validation group (ratio 1:1). The expression levels of HBx and TAM marker CD68 in HCC samples were detected by immunohistochemistry. Kaplan-Meier curves, Cox regression and Harrell's concordance index (C-index) analysis were conducted to evaluate the prognostic significance of these indicators alone or in combination. RESULTS The expression level of HBx was strongly correlated with CD68+ TAM infiltration in HCC tissues. Elevated HBx or CD68 expression indicated poorer overall survival (OS) and progression-free survival (PFS) after hepatectomy, and both of them were independent risk factors for postoperative survival. Meanwhile, patients with both high HBx and CD68 levels had worst clinical outcomes. Moreover, integrating HBx and CD68 expression with clinical indicators (tumor size and micro-vascular invasion) showed the best prognostic potential with highest C-index value for survival predictivity, and this proposed model also performed better than several conventional classifications of HCC. CONCLUSION Combining the expression of intratumoral HBx, CD68+ TAM population and clinical variables could enable better prognostication for HBV-related HCC after hepatectomy, thus providing novel insights into developing more effective clinical prediction model based on both molecular phenotypes and tumor-immune microenvironment.
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Affiliation(s)
- Ming-Da Wang
- Shanghai Health Commission Key Lab of Artificial Intelligence-Based Management of Inflammation and Chronic Diseases, Gongli Hospital, Navy Medical University, 219 Miaopu Road, Shanghai, 200135, China
- Department of Hepatobiliary Surgery, Eastern Hepatobiliary Surgery Hospital, Navy Medical University, Shanghai, 200433, China
| | - Hao Xiang
- The Third Affiliated Hospital of Zunyi Medical University, The First People's Hospital of Zunyi), Guizhou, 563000, China
| | - Tian-Yu Hong
- Shanghai Health Commission Key Lab of Artificial Intelligence-Based Management of Inflammation and Chronic Diseases, Gongli Hospital, Navy Medical University, 219 Miaopu Road, Shanghai, 200135, China
| | - Abudurexiti Mierxiati
- Shanghai Health Commission Key Lab of Artificial Intelligence-Based Management of Inflammation and Chronic Diseases, Gongli Hospital, Navy Medical University, 219 Miaopu Road, Shanghai, 200135, China
| | - Fei-Hu Yan
- Department of Colorectal Surgery, Shanghai Changhai Hospital, Navy Medical University, Shanghai, 200433, China.
| | - Ling Zhang
- Department of Obstetrics and Gynecology, School of Medicine, Chengdu Women's and Children's Central Hospital, University of Electronic Science and Technology of China, Sichuan, 610000, China.
| | - Chao Wang
- Shanghai Health Commission Key Lab of Artificial Intelligence-Based Management of Inflammation and Chronic Diseases, Gongli Hospital, Navy Medical University, 219 Miaopu Road, Shanghai, 200135, China.
- Department of Urinary Surgery, Gongli Hospital, Navy Medical University, Shanghai, 200135, China.
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9
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Jin Y, Wang S, Xu S, Zhao S, Xu X, Poongavanam V, Menéndez-Arias L, Zhan P, Liu X. Targeting hepatitis B virus cccDNA levels: recent progress in seeking small molecule drug candidates. Drug Discov Today 2023; 28:103617. [PMID: 37196762 DOI: 10.1016/j.drudis.2023.103617] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2023] [Revised: 03/29/2023] [Accepted: 05/10/2023] [Indexed: 05/19/2023]
Abstract
Hepatitis B virus (HBV) infection is a major global health problem that puts people at high risk of death from cirrhosis and liver cancer. The presence of covalently closed circular DNA (cccDNA) in infected cells is considered to be the main obstacle to curing chronic hepatitis B. At present, the cccDNA cannot be completely eliminated by standard treatments. There is an urgent need to develop drugs or therapies that can reduce HBV cccDNA levels in infected cells. We summarize the discovery and optimization of small molecules that target cccDNA synthesis and degradation. These compounds are cccDNA synthesis inhibitors, cccDNA reducers, core protein allosteric modulators, ribonuclease H inhibitors, cccDNA transcriptional modulators, HBx inhibitors and other small molecules that reduce cccDNA levels. Teaser: HBV covalently closed circular DNA (cccDNA) can be stably maintained in infected cells for a prolonged period, and this is the fundamental reason why hepatitis B cannot be completely cured. Here, we review recent progress in the development of small molecules that can reduce cccDNA levels in infected cells.
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Affiliation(s)
- Yu Jin
- Department of Medicinal Chemistry, Key Laboratory of Chemical Biology (Ministry of Education), School of Pharmaceutical Sciences, Shandong University, 44 West Culture Road, 250012 Jinan, Shandong, PR China
| | - Shuo Wang
- Department of Medicinal Chemistry, Key Laboratory of Chemical Biology (Ministry of Education), School of Pharmaceutical Sciences, Shandong University, 44 West Culture Road, 250012 Jinan, Shandong, PR China
| | - Shujing Xu
- Department of Medicinal Chemistry, Key Laboratory of Chemical Biology (Ministry of Education), School of Pharmaceutical Sciences, Shandong University, 44 West Culture Road, 250012 Jinan, Shandong, PR China
| | - Shujie Zhao
- Department of Medicinal Chemistry, Key Laboratory of Chemical Biology (Ministry of Education), School of Pharmaceutical Sciences, Shandong University, 44 West Culture Road, 250012 Jinan, Shandong, PR China
| | - Xiangrui Xu
- Department of Medicinal Chemistry, Key Laboratory of Chemical Biology (Ministry of Education), School of Pharmaceutical Sciences, Shandong University, 44 West Culture Road, 250012 Jinan, Shandong, PR China
| | - Vasanthanathan Poongavanam
- Department of Physics, Chemistry and Pharmacy, University of Southern Denmark, Odense M, DK-5230, Denmark
| | - Luis Menéndez-Arias
- Centro de Biología Molecular 'Severo Ochoa' (Consejo Superior de Investigaciones Científicas & Universidad Autónoma de Madrid), 28049 Madrid, Spain.
| | - Peng Zhan
- Department of Medicinal Chemistry, Key Laboratory of Chemical Biology (Ministry of Education), School of Pharmaceutical Sciences, Shandong University, 44 West Culture Road, 250012 Jinan, Shandong, PR China.
| | - Xinyong Liu
- Department of Medicinal Chemistry, Key Laboratory of Chemical Biology (Ministry of Education), School of Pharmaceutical Sciences, Shandong University, 44 West Culture Road, 250012 Jinan, Shandong, PR China.
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10
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He L, Shen H, Deng H, Zhang X, Xu Y, Shi C, Ouyang Z. Identification of critical residues in the regulatory protein HBx for Smc5/6 interaction and hepatitis B virus production. Antiviral Res 2023; 211:105519. [PMID: 36592669 DOI: 10.1016/j.antiviral.2022.105519] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2022] [Revised: 12/13/2022] [Accepted: 12/28/2022] [Indexed: 01/01/2023]
Abstract
The host structural maintenance of chromosomes 5/6 complex (Smc5/6) is a restriction factor of hepatitis B virus (HBV) that inhibits the transcription of viral ccDNA. HBV antagonizes this restriction by expressing the regulatory X protein (HBx) which targets Smc5/6 for degradation via DNA damage-binding protein 1 (DDB1) E3 ubiquitin ligase. However, the molecular insights into how Smc5/6 interacts with HBx remain elusive. In this study, we systematically investigated the interaction between Smc5/6 and HBx. Smc5/6 interacts with HBx through multiple sites in the absence of DDB1 in the pull-down assay. HBx C-terminal is sufficient for the interaction. Most importantly, residue Phe132, which is strictly conserved in all HBV subtypes, is critical for interaction with Smc5/6 both in vitro and in vivo. Mutation of this site (F132A) results in defect in Smc5/6 interaction, extrachromosomal reporter transcription, and HBV production both in cells and in mouse model. Collectively, our data identifies a key residue on HBx for Smc5/6 interaction and viral production. These results provide valuable information for both basic research and therapeutic drugs targeting HBx.
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Affiliation(s)
- Lili He
- Department of Pathogen Biology, School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology, 13 Hangkong Road, Wuhan, Hubei province, 430030, China
| | - Huanyu Shen
- Department of Pathogen Biology, School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology, 13 Hangkong Road, Wuhan, Hubei province, 430030, China
| | - Hui Deng
- Department of Pathogen Biology, School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology, 13 Hangkong Road, Wuhan, Hubei province, 430030, China
| | - Xiaoyan Zhang
- Department of Pathogen Biology, School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology, 13 Hangkong Road, Wuhan, Hubei province, 430030, China
| | - Yang Xu
- Department of Pathogen Biology, School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology, 13 Hangkong Road, Wuhan, Hubei province, 430030, China
| | - Chunwei Shi
- Department of Pathogen Biology, School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology, 13 Hangkong Road, Wuhan, Hubei province, 430030, China
| | - Zhuqing Ouyang
- Department of Pathogen Biology, School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology, 13 Hangkong Road, Wuhan, Hubei province, 430030, China.
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11
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Tumor Suppressor p53 Inhibits Hepatitis B Virus Replication by Downregulating HBx via E6AP-Mediated Proteasomal Degradation in Human Hepatocellular Carcinoma Cell Lines. Viruses 2022; 14:v14102313. [PMID: 36298868 PMCID: PMC9609658 DOI: 10.3390/v14102313] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2022] [Revised: 10/18/2022] [Accepted: 10/19/2022] [Indexed: 11/06/2022] Open
Abstract
HBx, a multifunctional regulatory protein, plays an essential role in the replication and pathogenesis of the hepatitis B virus (HBV). In this study, we found that in human hepatoma cells, the tumor suppressor p53 downregulates HBx via ubiquitin-dependent proteasomal degradation. p53 transcriptional activity that results from HBV infection was not essential for this effect. This was shown by treatment with a potent p53 inhibitor, pifithrin-α. Instead, we found that p53 facilitated the binding of E6-associated protein (E6AP), which is an E3 ligase, to HBx and induced E6AP-mediated HBx ubiquitination in a ternary complex of p53, E6AP, and HBx. The ability of p53 to induce E6AP-mediated downregulation of HBx and inhibit HBV replication was demonstrated in an in vitro HBV infection system. This study may provide insights into the regulation of HBx and HBV replication, especially with respect to p53 status, which may also help in understanding HBV-associated tumorigenesis in patients.
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12
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Antiviral Compounds Screening Targeting HBx Protein of the Hepatitis B Virus. Int J Mol Sci 2022; 23:ijms231912015. [PMID: 36233317 PMCID: PMC9569680 DOI: 10.3390/ijms231912015] [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: 09/13/2022] [Revised: 09/30/2022] [Accepted: 10/07/2022] [Indexed: 11/21/2022] Open
Abstract
A functional cure of hepatitis B virus (HBV) infection or HB antigen loss is rarely achieved by nucleos(t)ide analogs which target viral polymerase. HBx protein is a regulatory protein associated with HBV replication. We thought to identify antiviral compounds targeting HBx protein by analyzing HBx binding activity. Recombinant GST-tagged HBx protein was applied on an FDA-approved drug library chip including 1018 compounds to determine binding affinity by surface plasmon resonance imaging (SPRi) using a PlexArray HT system. GST protein alone was used for control experiments. Candidate compounds were tested for anti-HBV activity as well as cell viability using HepG2.2.15.7 cells and HBV-infected human hepatocytes. Of the 1018 compounds screened, 24 compounds showed binding to HBx protein. Of the top 6 compounds with high affinity to HBx protein, tranilast was found to inhibit HBV replication without affecting cell viability using HepG2.2.15.7 cells. Tranilast also inhibited HBV infection using cultured human hepatocytes. Tranilast reduced HB antigen level dose-dependently. Overall, theSPRi screening assay identified novel drug candidates targeting HBx protein. Tranilast and its related compounds warrant further investigation for the treatment of HBV infection.
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13
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Feitelson MA, Arzumanyan A, Spector I, Medhat A. Hepatitis B x (HBx) as a Component of a Functional Cure for Chronic Hepatitis B. Biomedicines 2022; 10:biomedicines10092210. [PMID: 36140311 PMCID: PMC9496119 DOI: 10.3390/biomedicines10092210] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2022] [Revised: 08/22/2022] [Accepted: 09/02/2022] [Indexed: 11/20/2022] Open
Abstract
Patients who are carriers of the hepatitis B virus (HBV) are at high risk of chronic liver disease (CLD) which proceeds from hepatitis, to fibrosis, cirrhosis and to hepatocellular carcinoma (HCC). The hepatitis B-encoded X antigen, HBx, promotes virus gene expression and replication, protects infected hepatocytes from immunological destruction, and promotes the development of CLD and HCC. For virus replication, HBx regulates covalently closed circular (ccc) HBV DNA transcription, while for CLD, HBx triggers cellular oxidative stress, in part, by triggering mitochondrial damage that stimulates innate immunity. Constitutive activation of NF-κB by HBx transcriptionally activates pro-inflammatory genes, resulting in hepatocellular destruction, regeneration, and increased integration of the HBx gene into the host genome. NF-κB is also hepatoprotective, which sustains the survival of infected cells. Multiple therapeutic approaches include direct-acting anti-viral compounds and immune-stimulating drugs, but functional cures were not achieved, in part, because none were yet devised to target HBx. In addition, many patients with cirrhosis or HCC have little or no virus replication, but continue to express HBx from integrated templates, suggesting that HBx contributes to the pathogenesis of CLD. Blocking HBx activity will, therefore, impact multiple aspects of the host–virus relationship that are relevant to achieving a functional cure.
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Affiliation(s)
- Mark A. Feitelson
- Room 409 Biolife Building, Department of Biology, College of Science and Technology, Temple University, 1900 N. 12th Street, Philadelphia, PA 19122, USA
- Correspondence: ; Tel.: +1-215-204-8434
| | - Alla Arzumanyan
- Room 409 Biolife Building, Department of Biology, College of Science and Technology, Temple University, 1900 N. 12th Street, Philadelphia, PA 19122, USA
| | | | - Arvin Medhat
- Department of Molecular Cell Biology, Islamic Azad University Tehran North Branch, Tehran 1975933411, Iran
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14
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Park ES, Dezhbord M, Lee AR, Park BB, Kim KH. Dysregulation of Liver Regeneration by Hepatitis B Virus Infection: Impact on Development of Hepatocellular Carcinoma. Cancers (Basel) 2022; 14:cancers14153566. [PMID: 35892823 PMCID: PMC9329784 DOI: 10.3390/cancers14153566] [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: 06/29/2022] [Revised: 07/19/2022] [Accepted: 07/21/2022] [Indexed: 02/04/2023] Open
Abstract
The liver is unique in its ability to regenerate in response to damage. The complex process of liver regeneration consists of multiple interactive pathways. About 2 billion people worldwide have been infected with hepatitis B virus (HBV), and HBV causes 686,000 deaths each year due to its complications. Long-term infection with HBV, which causes chronic inflammation, leads to serious liver-related diseases, including cirrhosis and hepatocellular carcinoma. HBV infection has been reported to interfere with the critical mechanisms required for liver regeneration. In this review, the studies on liver tissue characteristics and liver regeneration mechanisms are summarized. Moreover, the inhibitory mechanisms of HBV infection in liver regeneration are investigated. Finally, the association between interrupted liver regeneration and hepatocarcinogenesis, which are both triggered by HBV infection, is outlined. Understanding the fundamental and complex liver regeneration process is expected to provide significant therapeutic advantages for HBV-associated hepatocellular carcinoma.
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Affiliation(s)
- Eun-Sook Park
- Institute of Biomedical Science and Technology, School of Medicine, Konkuk University, Seoul 05029, Korea; (E.-S.P.); (B.B.P.)
| | - Mehrangiz Dezhbord
- Department of Precision Medicine, School of Medicine, Sungkyunkwan University, Suwon 16419, Korea; (M.D.); (A.R.L.)
| | - Ah Ram Lee
- Department of Precision Medicine, School of Medicine, Sungkyunkwan University, Suwon 16419, Korea; (M.D.); (A.R.L.)
| | - Bo Bae Park
- Institute of Biomedical Science and Technology, School of Medicine, Konkuk University, Seoul 05029, Korea; (E.-S.P.); (B.B.P.)
| | - Kyun-Hwan Kim
- Department of Precision Medicine, School of Medicine, Sungkyunkwan University, Suwon 16419, Korea; (M.D.); (A.R.L.)
- Correspondence: ; Tel.: +82-31-299-6126
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15
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Abstract
Hepatitis B virus (HBV)‐related diseases are among the major diseases that affect millions of people worldwide. These diseases are difficult to eradicate and thus pose a serious global health challenge. There is an urgent need to understand the cross talk mechanism between HBV and the host. Cholesterol‐25‐hydroxylase (CH25H) and its enzymatic product, 25‐hydroxycholesterol (25HC), were previously shown to exhibit effective broad‐spectrum antiviral activity. However, the role of CH25H in the regulation of HBV infection and replication remains unclear. The present study reported increased expression of CH25H in HBV-infected patients compared to healthy subjects. Importantly, higher expression of CH25H expression was found to be associated with low HBV replication. Additionally, the present study aimed to identify CH25H mutants, which would lack hydroxylase activity but retain antiviral activity toward HBV infection and replication. Interestingly, it was observed that both CH25H and its mutants interacted with HBx protein and inhibited nuclear translocation of HBx. In particular, CH25H interacted with the C-terminal region of HBx, while transmembrane region 3 of CH25H was found to be critical for CH25H–HBx interaction and inhibition of HBV replication. The study results suggested that 25HC promoted HBV infection but not HBV replication. Thus, the results of the present study suggested the involvement of a dual mechanism in CH25H-mediated regulation of HBV replication. The study clearly demonstrated cross talk between HBV and the host through CH25H–HBx axis.
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16
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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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17
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Lee S, Yoon H, Han J, Jang KL. Hepatitis C virus core protein inhibits hepatitis B virus replication by downregulating HBx levels via Siah-1-mediated proteasomal degradation during coinfection. J Gen Virol 2021; 102. [PMID: 34882535 DOI: 10.1099/jgv.0.001701] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Most clinical and experimental studies have suggested that hepatitis C virus (HCV) is dominant over hepatitis B virus (HBV) during coinfection, although the mechanism remains unclear. Here, we found that HCV core protein inhibits HBV replication by downregulating HBx levels during coinfection in human hepatoma cells. For this effect, HCV core protein increased reactive oxygen species levels in the mitochondria and activated the ataxia telangiectasia mutated-checkpoint kinase two pathway in the nucleus, resulting in an upregulation of p53 levels. Accordingly, HCV core protein induced p53-dependent activation of seven in absentia homolog one expression, an E3 ligase of HBx, resulting in the ubiquitination and proteasomal degradation of HBx. The effect of the HCV core protein on HBx levels was accurately reproduced in both a 1.2-mer HBV replicon and in vitro HBV infection systems, providing evidence for the inhibition of HBV replication by HCV core protein. The present study may provide insights into the mechanism of HCV dominance in HBV- and HCV-coinfected patients.
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Affiliation(s)
- Sujeong Lee
- Department of Integrated Biological Science, The Graduate School, Pusan National University, Busan 46241, Republic of Korea
| | - Hyunyoung Yoon
- Department of Integrated Biological Science, The Graduate School, Pusan National University, Busan 46241, Republic of Korea
| | - Jiwoo Han
- Department of Integrated Biological Science, The Graduate School, Pusan National University, Busan 46241, Republic of Korea
| | - Kyung Lib Jang
- Department of Integrated Biological Science, The Graduate School, Pusan National University, Busan 46241, Republic of Korea.,Department of Microbiology, College of Natural Science, Pusan National University, Busan 46241, Republic of Korea.,Microbiological Resource Research Institute, Pusan National University, Busan 46241, Republic of Korea
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18
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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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19
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Han J, Kim H, Jeong H, Yoon H, Jang KL. Proteasomal activator 28 gamma stabilizes hepatitis B virus X protein by competitively inhibiting the Siah-1-mediated proteasomal degradation. Biochem Biophys Res Commun 2021; 578:97-103. [PMID: 34555669 DOI: 10.1016/j.bbrc.2021.09.028] [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] [Received: 09/09/2021] [Accepted: 09/14/2021] [Indexed: 12/17/2022]
Abstract
Proteasomal activator 28 gamma (PA28γ) upregulates the levels of HBx, a regulatory protein of hepatitis B virus (HBV) to stimulate HBV replication; however, the detailed mechanism remains unknown. Here, we found that PA28γ impaired the ability of seven in absentia homolog 1 (Siah-1) as an E3 ubiquitin ligase of HBx. PA28γ competitively inhibited the binding of Siah-1 to HBx in human hepatoma cells. Accordingly, PA28γ increased the stability of HBx and decreased HBx ubiquitination, abolishing the potential of Siah-1 to downregulate HBx levels. PA28γ also executed its role as an antagonist of Siah-1 during HBV replication, as demonstrated by an in vitro HBV replication system. The present study may provide insights into the mechanisms underlying the regulation of HBV replication.
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Affiliation(s)
- Jiwoo Han
- Department of Microbiology, College of Natural Science, Pusan National University, Busan, 46241, Republic of Korea
| | - Haeji Kim
- Department of Microbiology, College of Natural Science, Pusan National University, Busan, 46241, Republic of Korea
| | - Hyerin Jeong
- Department of Microbiology, College of Natural Science, Pusan National University, Busan, 46241, Republic of Korea
| | - Hyunyoung Yoon
- Department of Microbiology, College of Natural Science, Pusan National University, Busan, 46241, Republic of Korea
| | - Kyung Lib Jang
- Department of Microbiology, College of Natural Science, Pusan National University, Busan, 46241, Republic of Korea; Microbiological Resource Research Institute, Pusan National University, Busan, 46241, Republic of Korea.
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20
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Romualdo GR, Leroy K, Costa CJS, Prata GB, Vanderborght B, da Silva TC, Barbisan LF, Andraus W, Devisscher L, Câmara NOS, Vinken M, Cogliati B. In Vivo and In Vitro Models of Hepatocellular Carcinoma: Current Strategies for Translational Modeling. Cancers (Basel) 2021; 13:5583. [PMID: 34771745 PMCID: PMC8582701 DOI: 10.3390/cancers13215583] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2021] [Revised: 11/02/2021] [Accepted: 11/04/2021] [Indexed: 12/24/2022] Open
Abstract
Hepatocellular carcinoma (HCC) is the sixth most common cancer worldwide and the third leading cause of cancer-related death globally. HCC is a complex multistep disease and usually emerges in the setting of chronic liver diseases. The molecular pathogenesis of HCC varies according to the etiology, mainly caused by chronic hepatitis B and C virus infections, chronic alcohol consumption, aflatoxin-contaminated food, and non-alcoholic fatty liver disease associated with metabolic syndrome or diabetes mellitus. The establishment of HCC models has become essential for both basic and translational research to improve our understanding of the pathophysiology and unravel new molecular drivers of this disease. The ideal model should recapitulate key events observed during hepatocarcinogenesis and HCC progression in view of establishing effective diagnostic and therapeutic strategies to be translated into clinical practice. Despite considerable efforts currently devoted to liver cancer research, only a few anti-HCC drugs are available, and patient prognosis and survival are still poor. The present paper provides a state-of-the-art overview of in vivo and in vitro models used for translational modeling of HCC with a specific focus on their key molecular hallmarks.
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Affiliation(s)
- Guilherme Ribeiro Romualdo
- Department of Pathology, School of Veterinary Medicine and Animal Science, University of São Paulo (USP), São Paulo 05508-270, Brazil; (G.R.R.); (C.J.S.C.); (T.C.d.S.)
- Department of Structural and Functional Biology, Biosciences Institute, São Paulo State University (UNESP), Botucatu 18618-689, Brazil; (G.B.P.); (L.F.B.)
- Department of Pathology, Botucatu Medical School, São Paulo State University (UNESP), Botucatu 18618-687, Brazil
| | - Kaat Leroy
- Department of Pharmaceutical and Pharmacological Sciences, Vrije Universiteit Brussel, 1090 Brussels, Belgium; (K.L.); (M.V.)
| | - Cícero Júlio Silva Costa
- Department of Pathology, School of Veterinary Medicine and Animal Science, University of São Paulo (USP), São Paulo 05508-270, Brazil; (G.R.R.); (C.J.S.C.); (T.C.d.S.)
| | - Gabriel Bacil Prata
- Department of Structural and Functional Biology, Biosciences Institute, São Paulo State University (UNESP), Botucatu 18618-689, Brazil; (G.B.P.); (L.F.B.)
- Department of Pathology, Botucatu Medical School, São Paulo State University (UNESP), Botucatu 18618-687, Brazil
| | - Bart Vanderborght
- Gut-Liver Immunopharmacology Unit, Basic and Applied Medical Sciences, Liver Research Center Ghent, Faculty of Medicine and Health Sciences, Ghent University, 9000 Ghent, Belgium;
- Hepatology Research Unit, Internal Medicine and Paediatrics, Liver Research Center Ghent, Faculty of Medicine and Health Sciences, Ghent University, 9000 Ghent, Belgium;
| | - Tereza Cristina da Silva
- Department of Pathology, School of Veterinary Medicine and Animal Science, University of São Paulo (USP), São Paulo 05508-270, Brazil; (G.R.R.); (C.J.S.C.); (T.C.d.S.)
| | - Luís Fernando Barbisan
- Department of Structural and Functional Biology, Biosciences Institute, São Paulo State University (UNESP), Botucatu 18618-689, Brazil; (G.B.P.); (L.F.B.)
| | - Wellington Andraus
- Department of Gastroenterology, Clinics Hospital, School of Medicine, University of São Paulo (HC-FMUSP), São Paulo 05403-000, Brazil;
| | - Lindsey Devisscher
- Hepatology Research Unit, Internal Medicine and Paediatrics, Liver Research Center Ghent, Faculty of Medicine and Health Sciences, Ghent University, 9000 Ghent, Belgium;
| | - Niels Olsen Saraiva Câmara
- Department of Immunology, Institute of Biomedical Sciences IV, University of São Paulo (USP), São Paulo 05508-000, Brazil;
| | - Mathieu Vinken
- Department of Pharmaceutical and Pharmacological Sciences, Vrije Universiteit Brussel, 1090 Brussels, Belgium; (K.L.); (M.V.)
| | - Bruno Cogliati
- Department of Pathology, School of Veterinary Medicine and Animal Science, University of São Paulo (USP), São Paulo 05508-270, Brazil; (G.R.R.); (C.J.S.C.); (T.C.d.S.)
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21
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Dubey AR, Jagtap YA, Kumar P, Patwa SM, Kinger S, Kumar A, Singh S, Prasad A, Jana NR, Mishra A. Biochemical strategies of E3 ubiquitin ligases target viruses in critical diseases. J Cell Biochem 2021; 123:161-182. [PMID: 34520596 DOI: 10.1002/jcb.30143] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2021] [Revised: 07/23/2021] [Accepted: 08/24/2021] [Indexed: 12/15/2022]
Abstract
Viruses are known to cause various diseases in human and also infect other species such as animal plants, fungi, and bacteria. Replication of viruses depends upon their interaction with hosts. Human cells are prone to such unwanted viral infections. Disintegration and reconstitution require host machinery and various macromolecules like DNA, RNA, and proteins are invaded by viral particles. E3 ubiquitin ligases are known for their specific function, that is, recognition of their respective substrates for intracellular degradation. Still, we do not understand how ubiquitin proteasome system-based enzymes E3 ubiquitin ligases do their functional interaction with different viruses. Whether E3 ubiquitin ligases help in the elimination of viral components or viruses utilize their molecular capabilities in their intracellular propagation is not clear. The first time our current article comprehends fundamental concepts and new insights on the different viruses and their interaction with various E3 Ubiquitin Ligases. In this review, we highlight the molecular pathomechanism of viruses linked with E3 Ubiquitin Ligases dependent mechanisms. An enhanced understanding of E3 Ubiquitin Ligase-mediated removal of viral proteins may open new therapeutic strategies against viral infections.
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Affiliation(s)
- Ankur R Dubey
- Department of Bioscience and Bioengineering, Cellular and Molecular Neurobiology Unit, Indian Institute of Technology Jodhpur, Jodhpur, Rajasthan, India
| | - Yuvraj A Jagtap
- Department of Bioscience and Bioengineering, Cellular and Molecular Neurobiology Unit, Indian Institute of Technology Jodhpur, Jodhpur, Rajasthan, India
| | - Prashant Kumar
- Department of Bioscience and Bioengineering, Cellular and Molecular Neurobiology Unit, Indian Institute of Technology Jodhpur, Jodhpur, Rajasthan, India
| | - Som M Patwa
- Department of Bioscience and Bioengineering, Cellular and Molecular Neurobiology Unit, Indian Institute of Technology Jodhpur, Jodhpur, Rajasthan, India
| | - Sumit Kinger
- Department of Bioscience and Bioengineering, Cellular and Molecular Neurobiology Unit, Indian Institute of Technology Jodhpur, Jodhpur, Rajasthan, India
| | - Amit Kumar
- Department of Biosciences and Biomedical Engineering, Indian Institute of Technology Indore, Indore, India
| | - Sarika Singh
- Department of Neuroscience and Ageing Biology, Division of Toxicology and Experimental Medicine, CSIR-Central Drug Research Institute, Lucknow, Uttar Pradesh, India
| | - Amit Prasad
- School of Basic Sciences, Indian Institute of Technology Mandi, Mandi, India
| | - Nihar R Jana
- School of Bioscience, Indian Institute of Technology Kharagpur, Kharagpur, India
| | - Amit Mishra
- Department of Bioscience and Bioengineering, Cellular and Molecular Neurobiology Unit, Indian Institute of Technology Jodhpur, Jodhpur, Rajasthan, India
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22
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Zhou Q, Yan L, Xu B, Wang X, Sun X, Han N, Tang H, Huang F. Screening of the HBx transactivation domain interacting proteins and the function of interactor Pin1 in HBV replication. Sci Rep 2021; 11:14176. [PMID: 34238995 PMCID: PMC8266847 DOI: 10.1038/s41598-021-93584-z] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2020] [Accepted: 06/28/2021] [Indexed: 02/05/2023] Open
Abstract
Hepatitis B virus (HBV) X protein (HBx) has been determined to play a crucial role in the replication and transcription of HBV, and its biological functions mainly depend on the interaction with other host proteins. This study aims at screening the proteins that bind to the key functional domain of HBx by integrated proteomics. Proteins that specifically bind to the transactivation domain of HBx were selected by comparing interactors of full-length HBx and HBx-D5 truncation determined by glutathione-S-transferase (GST) pull-down assay combined with mass spectrometry (MS). The function of HBx interactor Pin1 in HBV replication was further investigated by in vitro experiments. In this study, a total of 189 proteins were identified from HepG2 cells that specifically bind to the transactivation domain of HBx by GST pull-down and subsequent MS. After gene ontology (GO) analysis, Pin1 was selected as the protein with the highest score in the largest cluster functioning in protein binding, and also classified into the cluster of proteins with the function of structural molecule activity, which is of great potential to be involved in HBV life cycle. The interaction between Pin1 and HBx has been further confirmed by Ni2+-NTA pulldown assay, co-immunoprecipitation, and immunofluorescence microscopy. HBsAg and HBeAg levels significantly decreased in Pin1 expression inhibited HepG2.2.15 cells. Besides, the inhibition of Pin1 expression in HepG2 cells impeded the restored replication of HBx-deficient HBV repaired by ectopic HBx expression. In conclusion, our study identified Pin1 as an interactor binds to the transactivation domain of HBx, and suggested the potential association between Pin1 and the function of HBx in HBV replication.
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Affiliation(s)
- Qiaoxia Zhou
- Department of Forensic Pathology, West China School of Preclinical and Forensic Medicine, Sichuan University, No. 17 Third Renmin Road North, Chengdu, 610041, People's Republic of China
| | - Libo Yan
- Center of Infectious Diseases, West China Hospital of Sichuan University, No.37 Guo Xue Xiang, Chengdu, 610041, People's Republic of China.,Division of Infectious Diseases, State Key Laboratory of Biotherapy, Sichuan University, Chengdu, 610041, People's Republic of China
| | - Baofu Xu
- Department of Forensic Pathology, West China School of Preclinical and Forensic Medicine, Sichuan University, No. 17 Third Renmin Road North, Chengdu, 610041, People's Republic of China.,Xinxiang Key Laboratory of Forensic Science Evidence, School of Forensic Medicine, Xinxiang Medical University, Xinxiang, 453003, People's Republic of China
| | - Xue'er Wang
- Department of Forensic Pathology, West China School of Preclinical and Forensic Medicine, Sichuan University, No. 17 Third Renmin Road North, Chengdu, 610041, People's Republic of China
| | - Xuehong Sun
- Department of Forensic Pathology, West China School of Preclinical and Forensic Medicine, Sichuan University, No. 17 Third Renmin Road North, Chengdu, 610041, People's Republic of China
| | - Ning Han
- Center of Infectious Diseases, West China Hospital of Sichuan University, No.37 Guo Xue Xiang, Chengdu, 610041, People's Republic of China.,Division of Infectious Diseases, State Key Laboratory of Biotherapy, Sichuan University, Chengdu, 610041, People's Republic of China
| | - Hong Tang
- Center of Infectious Diseases, West China Hospital of Sichuan University, No.37 Guo Xue Xiang, Chengdu, 610041, People's Republic of China. .,Division of Infectious Diseases, State Key Laboratory of Biotherapy, Sichuan University, Chengdu, 610041, People's Republic of China.
| | - Feijun Huang
- Department of Forensic Pathology, West China School of Preclinical and Forensic Medicine, Sichuan University, No. 17 Third Renmin Road North, Chengdu, 610041, People's Republic of China.
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23
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Unique Features of Hepatitis B Virus-Related Hepatocellular Carcinoma in Pathogenesis and Clinical Significance. Cancers (Basel) 2021; 13:cancers13102454. [PMID: 34070067 PMCID: PMC8158142 DOI: 10.3390/cancers13102454] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2021] [Revised: 05/12/2021] [Accepted: 05/14/2021] [Indexed: 02/07/2023] Open
Abstract
Simple Summary Hepatitis B virus (HBV) infection is the major risk factor for hepatocellular carcinoma (HCC). Understanding the unique features for HBV-induced HCC can shed new light on the unmet needs in its early diagnosis and effective therapy. During decades of chronic hepatitis B, hepatocytes undergoing repeated damage and regeneration accumulate genetic changes predisposing to HCC development. In addition to traditional mutations in viral and cellular oncogenes, HBV integration into the cell chromosomes is an alternative genetic change contributing to hepatocarcinogenesis. A striking male dominance in HBV-related HCC further highlights an interaction between androgen sex hormone and viral factors, which contributes to the gender difference via stimulating viral replication and activation of oncogenes preferentially in male patients. Meanwhile, a novel circulating tumor biomarker generated by HBV integration shows great potential for the early diagnosis of HCC. These unique HBV-induced hepatocarcinogenic mechanisms provide new insights for the future development of superior diagnosis and treatment strategies. Abstract Hepatitis B virus (HBV) infection is one of the important risk factors for hepatocellular carcinoma (HCC) worldwide, accounting for around 50% of cases. Chronic hepatitis B infection generates an inflammatory microenvironment, in which hepatocytes undergoing repeated cycles of damage and regeneration accumulate genetic mutations predisposing them to cancer. A striking male dominance in HBV-related HCC highlights the influence of sex hormones which interact with viral factors to influence carcinogenesis. HBV is also considered an oncogenic virus since its X and surface mutant proteins showed tumorigenic activity in mouse models. The other unique mechanism is the insertional mutagenesis by integration of HBV genome into hepatocyte chromosomes to activate oncogenes. HCC survival largely depends on tumor stages at diagnosis and effective treatment. However, early diagnosis by the conventional protein biomarkers achieves limited success. A new biomarker, the circulating virus–host chimera DNA from HBV integration sites in HCC, provides a liquid biopsy approach for monitoring the tumor load in the majority of HBV–HCC patients. To maximize the efficacy of new immunotherapies or molecular target therapies, it requires better classification of HCC based on the tumor microenvironment and specific carcinogenic pathways. An in-depth study may benefit both the diagnosis and treatment of HBV-related HCC.
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24
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Takeuchi Y, Tsuge M, Tsushima K, Suehiro Y, Fujino H, Ono A, Yamauchi M, Makokha GN, Nakahara T, Murakami E, Abe-Chayama H, Kawaoka T, Miki D, Imamura M, Aikata H, Hayes CN, Tateno C, Chayama K. Signal Activation of Hepatitis B Virus-Related Hepatocarcinogenesis by Up-regulation of SUV39h1. J Infect Dis 2021; 222:2061-2070. [PMID: 32514521 DOI: 10.1093/infdis/jiaa317] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2020] [Accepted: 06/06/2020] [Indexed: 12/22/2022] Open
Abstract
BACKGROUND Hepatitis B virus (HBV) X (HBx) protein is associated with hepatocellular carcinogenesis via the induction of malignant transformation and mitochondrial dysfunction. However, the association between HBx and histone methyltransferase in carcinogenesis has not been fully clarified. In the current study, we analyzed the association between HBx and the histone methyltransferase suppressor of variegation 3-9 homolog 1 (SUV39h1) using HBV replication models. METHODS We constructed several HBx and SUV39h1 expression plasmids and analyzed the association between HBx and SUV39h1 with respect to HBV replication and hepatocarcinogenesis. RESULTS SUV39h1 up-regulation was observed in HBV-infected humanized mouse livers and clinical HBV-related hepatocellular carcinoma tissues, indicating that SUV39h1 expression might be regulated by HBV infection. Through in vitro analysis, we determined that the coactivator domain of HBx interacts with the PSET (PostSET) and SET (Su(var)3-9, Enhancer-of-zeste, Trithorax) domains of SUV39h1. The expression levels of 4 genes, activating transcription factor 6, α-fetoprotein, growth arrest and DNA damage-inducible 45a, and dual-specificity phosphatase 1, known to induce carcinogenesis via HBx expression, were up-regulated by HBx and further up-regulated in the presence of both HBx and SUV39h1. Furthermore, histone methyltransferase activity, the main function of SUV39h1, was enhanced in the presence of HBx. CONCLUSIONS We demonstrated that SUV39h1 and HBx enhance each other's activity, leading to HBx-mediated hepatocarcinogenesis. We propose that regulation of this interaction could help suppress development of hepatocellular carcinoma.
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Affiliation(s)
- Yasue Takeuchi
- Department of Gastroenterology and Metabolism, Graduate School of Biomedical & Health Sciences, Hiroshima University, Hiroshima, Japan.,Research Center for Hepatology and Gastroenterology, Hiroshima University, Hiroshima, Japan
| | - Masataka Tsuge
- Department of Gastroenterology and Metabolism, Graduate School of Biomedical & Health Sciences, Hiroshima University, Hiroshima, Japan.,Research Center for Hepatology and Gastroenterology, Hiroshima University, Hiroshima, Japan.,Natural Science Center for Basic Research and Development, Hiroshima University, Hiroshima, Japan
| | - Ken Tsushima
- Department of Gastroenterology and Metabolism, Graduate School of Biomedical & Health Sciences, Hiroshima University, Hiroshima, Japan.,Research Center for Hepatology and Gastroenterology, Hiroshima University, Hiroshima, Japan
| | - Yosuke Suehiro
- Department of Gastroenterology and Metabolism, Graduate School of Biomedical & Health Sciences, Hiroshima University, Hiroshima, Japan.,Research Center for Hepatology and Gastroenterology, Hiroshima University, Hiroshima, Japan
| | - Hatsue Fujino
- Department of Gastroenterology and Metabolism, Graduate School of Biomedical & Health Sciences, Hiroshima University, Hiroshima, Japan.,Research Center for Hepatology and Gastroenterology, Hiroshima University, Hiroshima, Japan
| | - Atsushi Ono
- Department of Gastroenterology and Metabolism, Graduate School of Biomedical & Health Sciences, Hiroshima University, Hiroshima, Japan.,Research Center for Hepatology and Gastroenterology, Hiroshima University, Hiroshima, Japan
| | - Masami Yamauchi
- Department of Gastroenterology and Metabolism, Graduate School of Biomedical & Health Sciences, Hiroshima University, Hiroshima, Japan.,Research Center for Hepatology and Gastroenterology, Hiroshima University, Hiroshima, Japan
| | - Grace Naswa Makokha
- Department of Gastroenterology and Metabolism, Graduate School of Biomedical & Health Sciences, Hiroshima University, Hiroshima, Japan.,Research Center for Hepatology and Gastroenterology, Hiroshima University, Hiroshima, Japan
| | - Takashi Nakahara
- Department of Gastroenterology and Metabolism, Graduate School of Biomedical & Health Sciences, Hiroshima University, Hiroshima, Japan.,Research Center for Hepatology and Gastroenterology, Hiroshima University, Hiroshima, Japan
| | - Eisuke Murakami
- Department of Gastroenterology and Metabolism, Graduate School of Biomedical & Health Sciences, Hiroshima University, Hiroshima, Japan.,Research Center for Hepatology and Gastroenterology, Hiroshima University, Hiroshima, Japan
| | - Hiromi Abe-Chayama
- Research Center for Hepatology and Gastroenterology, Hiroshima University, Hiroshima, Japan.,Center for Medical Specialist Graduate Education and Research, Institute of Biomedical and Health Sciences, Hiroshima University, Hiroshima, Japan
| | - Tomokazu Kawaoka
- Department of Gastroenterology and Metabolism, Graduate School of Biomedical & Health Sciences, Hiroshima University, Hiroshima, Japan.,Research Center for Hepatology and Gastroenterology, Hiroshima University, Hiroshima, Japan
| | - Daiki Miki
- Department of Gastroenterology and Metabolism, Graduate School of Biomedical & Health Sciences, Hiroshima University, Hiroshima, Japan.,Research Center for Hepatology and Gastroenterology, Hiroshima University, Hiroshima, Japan
| | - Michio Imamura
- Department of Gastroenterology and Metabolism, Graduate School of Biomedical & Health Sciences, Hiroshima University, Hiroshima, Japan.,Research Center for Hepatology and Gastroenterology, Hiroshima University, Hiroshima, Japan
| | - Hiroshi Aikata
- Department of Gastroenterology and Metabolism, Graduate School of Biomedical & Health Sciences, Hiroshima University, Hiroshima, Japan.,Research Center for Hepatology and Gastroenterology, Hiroshima University, Hiroshima, Japan
| | - C Nelson Hayes
- Department of Gastroenterology and Metabolism, Graduate School of Biomedical & Health Sciences, Hiroshima University, Hiroshima, Japan.,Research Center for Hepatology and Gastroenterology, Hiroshima University, Hiroshima, Japan
| | - Chise Tateno
- Research Center for Hepatology and Gastroenterology, Hiroshima University, Hiroshima, Japan.,PhoenixBio, Higashi-Hiroshima, Japan
| | - Kazuaki Chayama
- Department of Gastroenterology and Metabolism, Graduate School of Biomedical & Health Sciences, Hiroshima University, Hiroshima, Japan.,Research Center for Hepatology and Gastroenterology, Hiroshima University, Hiroshima, Japan.,Laboratory for Digestive Diseases, RIKEN Center for Integrative Medical Sciences, Hiroshima, Japan
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25
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Kruse RL, Barzi M, Legras X, Pankowicz FP, Furey N, Liao L, Xu J, Bissig-Choisat B, Slagle BL, Bissig KD. A hepatitis B virus transgenic mouse model with a conditional, recombinant, episomal genome. JHEP Rep 2021; 3:100252. [PMID: 33733079 PMCID: PMC7940981 DOI: 10.1016/j.jhepr.2021.100252] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/02/2020] [Revised: 12/27/2020] [Accepted: 01/04/2021] [Indexed: 01/21/2023] Open
Abstract
Background & Aims Development of new and more effective therapies against hepatitis B virus (HBV) is limited by the lack of suitable small animal models. The HBV transgenic mouse model containing an integrated overlength 1.3-mer construct has yielded crucial insights, but this model unfortunately lacks covalently closed circular DNA (cccDNA), the episomal HBV transcriptional template, and cannot be cured given that HBV is integrated in every cell. Methods To solve these 2 problems, we generated a novel transgenic mouse (HBV1.1X), which generates an excisable circular HBV genome using Cre/LoxP technology. This model possesses a HBV1.1-mer cassette knocked into the ROSA26 locus and is designed for stable expression of viral proteins from birth, like the current HBV transgenic mouse model, before genomic excision with the introduction of Cre recombinase. Results We demonstrated induction of recombinant cccDNA (rcccDNA) formation via viral or transgenic Cre expression in HBV1.1X mice, and the ability to regulate HBsAg and HBc expression with Cre in mice. Tamoxifen-inducible Cre could markedly downregulate baseline HBsAg levels from the integrated HBV genome. To demonstrate clearance of HBV from HBV1.1X mice, we administered adenovirus expressing Cre, which permanently and significantly reduced HBsAg and core antigen levels in the murine liver via rcccDNA excision and a subsequent immune response. Conclusions The HBV1.1X model is the first Cre-regulatable HBV transgenic mouse model and should be of value to mimic chronic HBV infection, with neonatal expression and tolerance of HBV antigens, and on-demand modulation of HBV expression. Lay summary Hepatitis B virus (HBV) can only naturally infect humans and chimpanzees. Mouse models have been developed with the HBV genome integrated into mouse chromosomes, but this prevents mice from being cured. We developed a new transgenic mouse model that allows for HBV to be excised from mouse chromosomes to form a recombinant circular DNA molecule resembling the natural circular HBV genome. HBV expression could be reduced in these mice, enabling curative therapies to be tested in this new mouse model.
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Affiliation(s)
- Robert L Kruse
- Center for Cell and Gene Therapy, Texas Children's Hospital, Houston Methodist Hospital, Baylor College of Medicine, Houston, TX, USA.,Center for Stem Cells and Regenerative Medicine, Baylor College of Medicine, Houston, TX, USA.,Translational Biology and Molecular Medicine Program, Baylor College of Medicine, Houston, TX, USA.,Medical Scientist Training Program, Baylor College of Medicine, Houston, TX, USA
| | - Mercedes Barzi
- Department of Pediatrics, Division of Medical Genetics, Duke University, Durham, NC, USA.,Y.T. and Alice Chen Pediatric Genetics and Genomics Research Center, Duke University, Durham, NC, USA
| | - Xavier Legras
- Department of Pediatrics, Division of Medical Genetics, Duke University, Durham, NC, USA.,Y.T. and Alice Chen Pediatric Genetics and Genomics Research Center, Duke University, Durham, NC, USA
| | - Francis P Pankowicz
- Center for Cell and Gene Therapy, Texas Children's Hospital, Houston Methodist Hospital, Baylor College of Medicine, Houston, TX, USA.,Center for Stem Cells and Regenerative Medicine, Baylor College of Medicine, Houston, TX, USA.,Department of Molecular and Cellular Biology, Baylor College of Medicine, Houston, TX, USA
| | - Nika Furey
- Center for Cell and Gene Therapy, Texas Children's Hospital, Houston Methodist Hospital, Baylor College of Medicine, Houston, TX, USA.,Center for Stem Cells and Regenerative Medicine, Baylor College of Medicine, Houston, TX, USA.,Department of Pediatrics, Division of Medical Genetics, Duke University, Durham, NC, USA.,Y.T. and Alice Chen Pediatric Genetics and Genomics Research Center, Duke University, Durham, NC, USA
| | - Lan Liao
- Department of Molecular and Cellular Biology, Baylor College of Medicine, Houston, TX, USA
| | - Janming Xu
- Department of Molecular and Cellular Biology, Baylor College of Medicine, Houston, TX, USA
| | - Beatrice Bissig-Choisat
- Center for Cell and Gene Therapy, Texas Children's Hospital, Houston Methodist Hospital, Baylor College of Medicine, Houston, TX, USA.,Center for Stem Cells and Regenerative Medicine, Baylor College of Medicine, Houston, TX, USA.,Department of Pediatrics, Division of Medical Genetics, Duke University, Durham, NC, USA.,Y.T. and Alice Chen Pediatric Genetics and Genomics Research Center, Duke University, Durham, NC, USA
| | - Betty L Slagle
- Department of Molecular Virology and Microbiology, Baylor College of Medicine, Houston, TX, USA
| | - Karl-Dimiter Bissig
- Center for Cell and Gene Therapy, Texas Children's Hospital, Houston Methodist Hospital, Baylor College of Medicine, Houston, TX, USA.,Center for Stem Cells and Regenerative Medicine, Baylor College of Medicine, Houston, TX, USA.,Translational Biology and Molecular Medicine Program, Baylor College of Medicine, Houston, TX, USA.,Department of Pediatrics, Division of Medical Genetics, Duke University, Durham, NC, USA.,Y.T. and Alice Chen Pediatric Genetics and Genomics Research Center, Duke University, Durham, NC, USA.,Department of Molecular and Cellular Biology, Baylor College of Medicine, Houston, TX, USA.,Duke Center for Virology, Duke University, Durham, NC, USA.,Duke Cancer Institute, Duke University, Durham, NC, USA
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26
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Dicoumarol, an NQO1 inhibitor, blocks cccDNA transcription by promoting degradation of HBx. J Hepatol 2021; 74:522-534. [PMID: 32987030 DOI: 10.1016/j.jhep.2020.09.019] [Citation(s) in RCA: 65] [Impact Index Per Article: 21.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/27/2020] [Revised: 09/06/2020] [Accepted: 09/14/2020] [Indexed: 12/16/2022]
Abstract
BACKGROUND & AIMS Current antiviral therapies help keep HBV under control, but they are not curative, as they are unable to eliminate the intracellular viral replication intermediate termed covalently closed circular DNA (cccDNA). Therefore, there remains an urgent need to develop strategies to cure CHB. Functional silencing of cccDNA is a crucial curative strategy that may be achieved by targeting the viral protein HBx. METHODS We screened 2,000 small-molecule compounds for their ability to inhibit HiBiT-tagged HBx (HiBiT-HBx) expression by using a HiBiT lytic detection system. The antiviral activity of a candidate compound and underlying mechanism of its effect on cccDNA transcription were evaluated in HBV-infected cells and a humanised liver mouse model. RESULTS Dicoumarol, an inhibitor of NAD(P)H:quinone oxidoreductase 1 (NQO1), significantly reduced HBx expression. Moreover, dicoumarol showed potent antiviral activity against HBV RNAs, HBV DNA, HBsAg and HBc protein in HBV-infected cells and a humanised liver mouse model. Mechanistic studies demonstrated that endogenous NQO1 binds to and protects HBx protein from 20S proteasome-mediated degradation. NQO1 knockdown or dicoumarol treatment significantly reduced the recruitment of HBx to cccDNA and inhibited the transcriptional activity of cccDNA, which was associated with the establishment of a repressive chromatin state. The absence of HBx markedly blocked the antiviral effect induced by NQO1 knockdown or dicoumarol treatment in HBV-infected cells. CONCLUSIONS Herein, we report on a novel small molecule that targets HBx to combat chronic HBV infection; we also reveal that NQO1 has a role in HBV replication through the regulation of HBx protein stability. LAY SUMMARY Current antiviral therapies for hepatitis B are not curative because of their inability to eliminate covalently closed circular DNA (cccDNA), which persists in the nuclei of infected cells. HBV X (HBx) protein has an important role in regulating cccDNA transcription. Thus, targeting HBx to silence cccDNA transcription could be an important curative strategy. We identified that the small molecule dicoumarol could block cccDNA transcription by promoting HBx degradation; this is a promising therapeutic strategy for the treatment of chronic hepatitis B.
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27
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HBV-Integration Studies in the Clinic: Role in the Natural History of Infection. Viruses 2021; 13:v13030368. [PMID: 33652619 PMCID: PMC7996909 DOI: 10.3390/v13030368] [Citation(s) in RCA: 46] [Impact Index Per Article: 15.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2021] [Revised: 02/21/2021] [Accepted: 02/22/2021] [Indexed: 02/06/2023] Open
Abstract
Hepatitis B virus (HBV) infection is a major global health problem causing acute and chronic liver disease that can lead to liver cirrhosis and hepatocellular carcinoma (HCC). HBV covalently closed circular DNA (cccDNA) is essential for viral replication and the establishment of a persistent infection. Integrated HBV DNA represents another stable form of viral DNA regularly observed in the livers of infected patients. HBV DNA integration into the host genome occurs early after HBV infection. It is a common occurrence during the HBV life cycle, and it has been detected in all the phases of chronic infection. HBV DNA integration has long been considered to be the main contributor to liver tumorigenesis. The recent development of highly sensitive detection methods and research models has led to the clarification of some molecular and pathogenic aspects of HBV integration. Though HBV integration does not lead to replication-competent transcripts, it can act as a stable source of viral RNA and proteins, which may contribute in determining HBV-specific T-cell exhaustion and favoring virus persistence. The relationship between HBV DNA integration and the immune response in the liver microenvironment might be closely related to the development and progression of HBV-related diseases. While many new antiviral agents aimed at cccDNA elimination or silencing have been developed, integrated HBV DNA remains a difficult therapeutic challenge.
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28
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Phosphorylation of Phylogenetically Conserved Amino Acid Residues Confines HBx within Different Cell Compartments of Human Hepatocarcinoma Cells. Molecules 2021; 26:molecules26051254. [PMID: 33652602 PMCID: PMC7956559 DOI: 10.3390/molecules26051254] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2020] [Revised: 02/20/2021] [Accepted: 02/20/2021] [Indexed: 01/05/2023] Open
Abstract
Hepatitis B virus (HBV) is a circular, and partially double-stranded DNA virus. Upon infection, the viral genome is translocated into the cell nucleus, generating the covalently closed circular DNA (cccDNA) intermediate, and forming a mini chromosome. HBV HBx is a small protein displaying multiple roles in HBV-infected cells, and in different subcellular locations. In the nucleus, the HBx protein is required to initiate and maintain viral transcription from the viral mini chromosome. In contrast, HBx also functions in the cytoplasm, where it is able to alter multiple cellular functions such as mitochondria metabolism, apoptosis and signal transduction pathways. It has been reported that in cultured cells, at low expression levels, the HBx protein is localized in the nucleus, whereas at high expression levels, it accumulates in the cytoplasm. This dynamic subcellular distribution of HBx might be essential to exert its multiple roles during viral infection. However, the mechanism that regulates different subcellular localizations of the HBx protein is unknown. We have previously taken a bioinformatics approach to investigate whether HBx might be regulated via post-translational modification, and we have proposed that the multiple nucleocytoplasmic functions of HBx might be regulated by an evolutionarily conserved mechanism via phosphorylation. In the current study, phylogenetically conserved amino acids of HBx with a high potential of phosphorylation were targeted for site-directed mutagenesis. Two conserved serine (Ser25 and Ser41), and one conserved threonine (Thr81) amino acids were replaced by either alanine or aspartic acid residues to simulate an unphosphorylated or phosphorylated state, respectively. Human hepatoma cells were transfected with increasing amounts of the HBx DNA constructs, and the cells were analyzed by fluorescence microscopy. Together, our results show that the nucleocytoplasmic distribution of the HBx protein could be regulated by phosphorylation since some of the modified proteins were mainly confined to distinct subcellular compartments. Remarkably, both HBx Ser41A, and HBx Thr81D proteins were predominantly localized within the nuclear compartment throughout the different expression levels of HBx mutants.
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29
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Risk Factors and Biomarkers for Chronic Hepatitis B Associated Hepatocellular Carcinoma. Int J Mol Sci 2021; 22:ijms22020479. [PMID: 33418899 PMCID: PMC7825109 DOI: 10.3390/ijms22020479] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2020] [Revised: 12/21/2020] [Accepted: 12/28/2020] [Indexed: 02/08/2023] Open
Abstract
Globally, hepatitis B virus (HBV) related hepatocellular carcinoma (HCC) is one of the major causes of cancer-related mortality. This is, in part, due to delayed diagnosis and limited therapeutic options with more advanced stages of the disease. Given the prognostic importance of early diagnosis, novel methods for early detection are in need. Unlike most other cancer types, tissue is not required to diagnose HCC and is frequently avoided given the inherent risks of liver biopsy, so less invasive methods of obtaining tumor material are currently under investigation. Material shed from tumors into the periphery are being investigated for their potential to both surveil and diagnose patients for HCC. These materials include circulating tumor cells, DNA, RNA, and exosomes, and are collectively termed a “liquid biopsy”. In this review article, we discuss the evolving literature regarding the different risk factors for HCC and the types of emerging novel biomarkers that show promise in the prevention and early diagnosis of HCC within the context of HBV infection.
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30
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Affiliation(s)
- Jie Li
- School of Medicine Huaqiao University Quanzhou 362021 P. R. China
| | - Jieqing Liu
- School of Medicine Huaqiao University Quanzhou 362021 P. R. China
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31
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Kruse RL, Legras X, Barzi M. Cre/LoxP-HBV plasmids generating recombinant covalently closed circular DNA genome upon transfection. Virus Res 2020; 292:198224. [PMID: 33166564 DOI: 10.1016/j.virusres.2020.198224] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2020] [Revised: 09/18/2020] [Accepted: 11/03/2020] [Indexed: 02/08/2023]
Abstract
New therapies against hepatitis B virus (HBV) require the elimination of covalently closed circular DNA (cccDNA), the episomal HBV genome. HBV plasmids containing an overlength 1.3-mer genome and bacterial backbone (pHBV1.3) are used in many different models, but do not replicate the unique features of cccDNA. Since the stable cccDNA pool is a barrier to HBV eradication in patients, we developed a recombinant circular HBV genome (rcccDNA) to mimic the cccDNA using Cre/LoxP technology. We validated four LoxP insertion sites into the HBV genome using hydrodynamic tail vein injection into murine liver, demonstrating high levels of HBV surface antigen (HBsAg) and HBV DNA expression with rcccDNA formation. HBsAg expression from rcccDNA was >30,000 ng/mL over 78 days, while HBsAg-expression from pHBV1.3 plasmid DNA declined from 2753 ng/mL to 131 ng/mL over that time in immunodeficient mice (P < 0.001), reflective of plasmid DNA silencing. We then cloned Cre-recombinase in cis on the LoxP-HBV plasmids, achieving plasmid stability in bacteria with intron insertion into Cre and demonstrating rcccDNA formation after transfection in vitro and in vivo. These cis-Cre/LoxP-HBV plasmids were then used to create HBx-mutant and GFP reporter plasmids to further probe cccDNA biology and antiviral strategies against cccDNA. Overall, we believe these auto-generating rcccDNA plasmids will be of great value to model cccDNA for testing new therapies against HBV infection.
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Affiliation(s)
- Robert L Kruse
- Center for Cell and Gene Therapy, Baylor College of Medicine, 1 Baylor Plaza, Houston, TX, 77030, USA.
| | - Xavier Legras
- Center for Cell and Gene Therapy, Baylor College of Medicine, 1 Baylor Plaza, Houston, TX, 77030, USA
| | - Mercedes Barzi
- Center for Cell and Gene Therapy, Baylor College of Medicine, 1 Baylor Plaza, Houston, TX, 77030, USA
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32
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Han N, Yan L, Wang X, Sun X, Huang F, Tang H. An updated literature review: how HBV X protein regulates the propagation of the HBV. Future Virol 2020. [DOI: 10.2217/fvl-2020-0251] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Chronic HBV infection constitutes a burden on human beings and is closely associated with hepatocellular carcinoma. The propagation of the HBV is determined by many factors, and the HBV X protein (HBx) could have a significant influence on this. HBx is a regulatory protein that can directly or indirectly interact with many cellular proteins to affect both the propagation of the HBV and the activity of the host cells. In this review, we summarized the possible mechanisms by which HBx regulates HBV replication at transcriptional and post-transcriptional levels in various experimental systems.
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Affiliation(s)
- Ning Han
- Center of Infectious Diseases, West China Hospital of Sichuan University, Chengdu, PR China
| | - Libo Yan
- Center of Infectious Diseases, West China Hospital of Sichuan University, Chengdu, PR China
| | - Xueer Wang
- Department of Forensic Pathology, West China School of Basic Science & Forensic Medicine, Sichuan University, Chengdu, Sichuan, PR China
| | - Xuehong Sun
- Department of Forensic Pathology, West China School of Basic Science & Forensic Medicine, Sichuan University, Chengdu, Sichuan, PR China
| | - Feijun Huang
- Department of Forensic Pathology, West China School of Basic Science & Forensic Medicine, Sichuan University, Chengdu, Sichuan, PR China
| | - Hong Tang
- Center of Infectious Diseases, West China Hospital of Sichuan University, Chengdu, PR China
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Lin CL, Chien RN, Chu YD, Liang KH, Huang YH, Ke PY, Lin KH, Lin YH, Yeh CT. Hepatitis B virus X gene mutants emerge during antiviral therapy and increase cccDNA levels to compensate for replication suppression. Hepatol Int 2020; 14:973-984. [PMID: 32770306 DOI: 10.1007/s12072-020-10079-1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/19/2020] [Accepted: 07/22/2020] [Indexed: 12/20/2022]
Abstract
BACKGROUND Hepatitis B virus (HBV) X gene (HBx) mutants can develop during the natural course of chronic HBV infection. However, little is known about whether the emergence of HBx mutants during long-term antiviral therapy is an adaptation of HBV to antiviral stress. This study was to identify HBx mutants that emerged in patients experiencing Lamivudine resistance or suboptimal treatment. METHODS Forty-six Lamivudine-resistant patients and 46 patients with suboptimal treatment responses to Entecavir were enrolled in this study. HBx mutants were identified by sequence analysis and their roles in the HBV replication cycle were characterized. RESULTS We show that deletion/truncation/insertion mutations were only detected in the Lamivudine resistance group, while synonymous mutations were found in both groups. Follow-up analyses revealed that five patients in the Lamivudine group developed hepatocellular carcinoma, while patients in the Entecavir group did not. These mutants were characterized by a significant decrease in transactivation of the pre-S1 promoter, and varying effects on transactivation of the X promoter. Co-transfection of HBx-mutant plasmid and HBV replication-competent clone into HepG2 cells resulted in increased nuclear-to-cytoplamic HBV core antigen, HBV-DNA ratios, and nuclear covalently closed circular DNA (cccDNA). Antiviral drug sensitivity assays revealed that these mutants exhibited a compensatory effect to counteract antiviral drug suppression, resulting in elevated secretory HBV-DNA levels. CONCLUSIONS Our study demonstrates that HBx mutants can emerge during Lamivudine or Entecavir therapy. These mutants exhibit altered transactivation of the HBV pre-S1 and X promoters, leading to increased cccDNA levels to compensate for replication suppression.
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Affiliation(s)
- Chih-Lang Lin
- Liver Research Unit, Keelung Chang Gung Memorial Hospital, Keelung, Taiwan.,Liver Research Center, Chang Gung Memorial Hospital, Linkou, Taoyuan, Taiwan.,College of Medicine, Chang Gung University, Taoyuan, Taiwan.,Community Medicine Research Center, Keelung Chang Gung Memorial Hospital, Keelung, Taiwan
| | - Rong-Nan Chien
- Liver Research Unit, Keelung Chang Gung Memorial Hospital, Keelung, Taiwan.,Liver Research Center, Chang Gung Memorial Hospital, Linkou, Taoyuan, Taiwan.,College of Medicine, Chang Gung University, Taoyuan, Taiwan.,Community Medicine Research Center, Keelung Chang Gung Memorial Hospital, Keelung, Taiwan
| | - Yu-De Chu
- Liver Research Center, Chang Gung Memorial Hospital, Linkou, Taoyuan, Taiwan
| | - Kung-Hao Liang
- Medical Research Department, Taipei Veterans General Hospital, Taipei, Taiwan
| | - Ya-Hui Huang
- Liver Research Center, Chang Gung Memorial Hospital, Linkou, Taoyuan, Taiwan.,College of Medicine, Chang Gung University, Taoyuan, Taiwan
| | - Po-Yuan Ke
- Department of Biochemistry, Chang Gung University, Taoyuan, Taiwan
| | - Kwang-Huei Lin
- Department of Biochemistry, Chang Gung University, Taoyuan, Taiwan
| | - Yang-Hsiang Lin
- Liver Research Center, Chang Gung Memorial Hospital, Linkou, Taoyuan, Taiwan. .,College of Medicine, Chang Gung University, Taoyuan, Taiwan.
| | - Chau-Ting Yeh
- Liver Research Center, Chang Gung Memorial Hospital, Linkou, Taoyuan, Taiwan. .,College of Medicine, Chang Gung University, Taoyuan, Taiwan. .,Medical Research Department, Taipei Veterans General Hospital, Taipei, Taiwan. .,Department of Biochemistry, Chang Gung University, Taoyuan, Taiwan.
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Discovery and Selection of Hepatitis B Virus-Derived T Cell Epitopes for Global Immunotherapy Based on Viral Indispensability, Conservation, and HLA-Binding Strength. J Virol 2020; 94:JVI.01663-19. [PMID: 31852786 PMCID: PMC7081907 DOI: 10.1128/jvi.01663-19] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2019] [Accepted: 12/10/2019] [Indexed: 12/15/2022] Open
Abstract
Multiple HBV-derived T cell epitopes have been reported, which can be useful in a therapeutic vaccination strategy. However, these epitopes are largely restricted to HLA-A*02, which is not dominantly expressed in populations with high HBV prevalence. Thus, current epitopes are falling short in the development of a global immunotherapeutic approach. Therefore, we aimed to identify novel epitopes for 6 HLA supertypes most prevalent in the infected population. Moreover, established epitopes might not all be equally effective as they can be subject to different levels of immune escape. It is therefore important to identify targets that are crucial in viral replication and conserved in the majority of the infected population. Here, we applied a stringent selection procedure to compose a combined overview of existing and novel HBV-derived T cell epitopes most promising for viral eradication. This set of T cell epitopes now lays the basis for the development of globally effective HBV antigen-specific immunotherapies. Immunotherapy represents an attractive option for the treatment of chronic hepatitis B virus (HBV) infection. The HBV proteins polymerase (Pol) and HBx are of special interest for antigen-specific immunotherapy because they are essential for viral replication and have been associated with viral control (Pol) or are still expressed upon viral DNA integration (HBx). Here, we scored all currently described HBx- and Pol-derived epitope sequences for viral indispensability and conservation across all HBV genotypes. This yielded 7 HBx-derived and 26 Pol-derived reported epitopes with functional association and high conservation. We subsequently predicted novel HLA-binding peptides for 6 HLA supertypes prevalent in HBV-infected patients. Potential epitopes expected to be the least prone to immune escape were subjected to a state-of-the-art in vitro assay to validate their HLA-binding capacity. Using this method, a total of 13 HLA binders derived from HBx and 33 binders from Pol were identified across HLA types. Subsequently, we demonstrated interferon gamma (IFN-γ) production in response to 5 of the novel HBx-derived binders and 17 of the novel Pol-derived binders. In addition, we validated several infrequently described epitopes. Collectively, these results specify a set of highly potent T cell epitopes that represent a valuable resource for future HBV immunotherapy design. IMPORTANCE Multiple HBV-derived T cell epitopes have been reported, which can be useful in a therapeutic vaccination strategy. However, these epitopes are largely restricted to HLA-A*02, which is not dominantly expressed in populations with high HBV prevalence. Thus, current epitopes are falling short in the development of a global immunotherapeutic approach. Therefore, we aimed to identify novel epitopes for 6 HLA supertypes most prevalent in the infected population. Moreover, established epitopes might not all be equally effective as they can be subject to different levels of immune escape. It is therefore important to identify targets that are crucial in viral replication and conserved in the majority of the infected population. Here, we applied a stringent selection procedure to compose a combined overview of existing and novel HBV-derived T cell epitopes most promising for viral eradication. This set of T cell epitopes now lays the basis for the development of globally effective HBV antigen-specific immunotherapies.
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35
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Park S, Ha YN, Dezhbord M, Lee AR, Park ES, Park YK, Won J, Kim NY, Choo SY, Shin JJ, Ahn CH, Kim KH. Suppression of Hepatocyte Nuclear Factor 4 α by Long-term Infection of Hepatitis B Virus Contributes to Tumor Cell Proliferation. Int J Mol Sci 2020; 21:ijms21030948. [PMID: 32023898 PMCID: PMC7037729 DOI: 10.3390/ijms21030948] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2019] [Revised: 01/24/2020] [Accepted: 01/29/2020] [Indexed: 12/15/2022] Open
Abstract
Hepatitis B virus (HBV) infection is a major factor in the development of various liver diseases such as hepatocellular carcinoma (HCC). Among HBV encoded proteins, HBV X protein (HBx) is known to play a key role in the development of HCC. Hepatocyte nuclear factor 4α (HNF4α) is a nuclear transcription factor which is critical for hepatocyte differentiation. However, the expression level as well as its regulatory mechanism in HBV infection have yet to be clarified. Here, we observed the suppression of HNF4α in cells which stably express HBV whole genome or HBx protein alone, while transient transfection of HBV replicon or HBx plasmid had no effect on the HNF4α level. Importantly, in the stable HBV- or HBx-expressing hepatocytes, the downregulated level of HNF4α was restored by inhibiting the ERK signaling pathway. Our data show that HNF4α was suppressed during long-term HBV infection in cultured HepG2-NTCP cells as well as in a mouse model following hydrodynamic injection of pAAV-HBV or in mice intravenously infected with rAAV-HBV. Importantly, HNF4α downregulation increased cell proliferation, which contributed to the formation and development of tumor in xenograft nude mice. The data presented here provide proof of the effect of HBV infection in manipulating the HNF4α regulatory pathway in HCC development.
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Affiliation(s)
| | | | | | | | | | | | | | | | | | | | | | - Kyun-Hwan Kim
- Correspondence: ; Tel.: +82-2-2030-7833; Fax: +82-2-2049-6192
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Host Transcription Factors in Hepatitis B Virus RNA Synthesis. Viruses 2020; 12:v12020160. [PMID: 32019103 PMCID: PMC7077322 DOI: 10.3390/v12020160] [Citation(s) in RCA: 40] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2019] [Revised: 01/27/2020] [Accepted: 01/28/2020] [Indexed: 02/06/2023] Open
Abstract
The hepatitis B virus (HBV) chronically infects over 250 million people worldwide and is one of the leading causes of liver cancer and hepatocellular carcinoma. HBV persistence is due in part to the highly stable HBV minichromosome or HBV covalently closed circular DNA (cccDNA) that resides in the nucleus. As HBV replication requires the help of host transcription factors to replicate, focusing on host protein–HBV genome interactions may reveal insights into new drug targets against cccDNA. The structural details on such complexes, however, remain poorly defined. In this review, the current literature regarding host transcription factors’ interactions with HBV cccDNA is discussed.
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HBV X protein mutations affect HBV transcription and association of histone-modifying enzymes with covalently closed circular DNA. Sci Rep 2020; 10:802. [PMID: 31964944 PMCID: PMC6972884 DOI: 10.1038/s41598-020-57637-z] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2019] [Accepted: 12/24/2019] [Indexed: 12/13/2022] Open
Abstract
The hepatitis B X protein (HBx) plays a role in the epigenetic regulation of hepatitis B virus (HBV) replication. This study investigated the effects of HBx mutations on HBV transcription and the recruitment of HBx, histone acetyl-transferase P300 and histone deacetylase 1 (HDAC1) to circularized HBV DNA (which resembles covalently closed circular DNA [cccDNA]). Compared with wild type, majority of mutants had lower levels of intracellular HBV RNA (44–77% reduction) and secretory HBsAg (25–81% reduction), and 12 mutants had a reduction in intracellular encapsidated HBV DNA (33–64% reduction). Eight mutants with >70% reduction in HBV RNA and/or HBsAg were selected for chromatin immunoprecipitation analysis. Four HBx mutants with mutations in amino acid residues 55–60 and 121–126 had a lower degree of HBx-cccDNA association than wild type HBx (mean % input: 0.02–0.64% vs. 3.08% in wild type). A reduced association between cccDNA and P300 (mean % input: 0.69–1.81% vs. 3.48% in wild type) and an augmented association with HDAC1 (mean % input: 4.01–14.0% vs. 1.53% in wild type) were detected. HBx amino acid residues 55–60 and 121–126 may play an important role in HBV transcription regulation, via their impeded interaction with cccDNA and altered recruitment of histone modifying enzymes to cccDNA.
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Rivière L, Quioc-Salomon B, Fallot G, Halgand B, Féray C, Buendia MA, Neuveut C. Hepatitis B virus replicating in hepatocellular carcinoma encodes HBx variants with preserved ability to antagonize restriction by Smc5/6. Antiviral Res 2019; 172:104618. [DOI: 10.1016/j.antiviral.2019.104618] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2019] [Revised: 08/08/2019] [Accepted: 10/05/2019] [Indexed: 12/26/2022]
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Li H, Yan L, Shi Y, Lv D, Shang J, Bai L, Tang H. Hepatitis B Virus Infection: Overview. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2019; 1179:1-16. [PMID: 31741331 DOI: 10.1007/978-981-13-9151-4_1] [Citation(s) in RCA: 35] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Hepatitis B virus (HBV) is a DNA virus, belonging to the Hepadnaviridae family. It is a partially double-stranded DNA virus with a small viral genome (3.2 kb). Chronic HBV infection remains a global public health problem. If left untreated, chronic HBV infection can progress to end-stage liver disease, such as liver cirrhosis and hepatocellular carcinoma (HCC). In recent years, tremendous advances in the field of HBV basic and clinical research have been achieved, ranging from the HBV biological characteristics, immunopathogenesis, and animal models to the development of new therapeutic strategies and new drugs against HBV. In this overview, we begin with a brief history of HBV discovery and treatment milestones. We then briefly summarize the HBV research advances, which will be detailed in the following chapters.
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Affiliation(s)
- Hong Li
- Center of Infectious Diseases, Division of Infectious Diseases, State Key Laboratory of Biotherapy, West China Hospital, Sichuan University, Chengdu, Sichuan, China
| | - Libo Yan
- Center of Infectious Diseases, Division of Infectious Diseases, State Key Laboratory of Biotherapy, West China Hospital, Sichuan University, Chengdu, Sichuan, China
| | - Ying Shi
- Center of Infectious Diseases, Division of Infectious Diseases, State Key Laboratory of Biotherapy, West China Hospital, Sichuan University, Chengdu, Sichuan, China
| | - Duoduo Lv
- Center of Infectious Diseases, Division of Infectious Diseases, State Key Laboratory of Biotherapy, West China Hospital, Sichuan University, Chengdu, Sichuan, China
| | - Jin Shang
- Center of Infectious Diseases, Division of Infectious Diseases, State Key Laboratory of Biotherapy, West China Hospital, Sichuan University, Chengdu, Sichuan, China
| | - Lang Bai
- Center of Infectious Diseases, Division of Infectious Diseases, State Key Laboratory of Biotherapy, West China Hospital, Sichuan University, Chengdu, Sichuan, China
| | - Hong Tang
- Center of Infectious Diseases, Division of Infectious Diseases, State Key Laboratory of Biotherapy, West China Hospital, Sichuan University, Chengdu, Sichuan, China.
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40
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Jeong H, Cha S, Jang KL. HBx natural variants containing Ser-101 instead of Pro-101 evade ubiquitin-dependent proteasomal degradation by activating proteasomal activator 28 gamma expression. J Gen Virol 2019; 100:1554-1566. [PMID: 31596196 DOI: 10.1099/jgv.0.001337] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
Proteasomal activator 28 gamma (PA28γ) is frequently overexpressed in hepatocellular carcinoma; however, its underlying mechanism and role in hepatitis B virus (HBV) replication are largely unknown. Here, we found that HBV X protein (HBx) natural variants containing Ser-101 instead of Pro-101 increase reactive oxygen species levels in the mitochondria and activate the ataxia telangiectasia mutated/checkpoint kinase 2 pathway in the nucleus, resulting in the phosphorylation of p53 at Ser-15 and Ser-20 and the subsequent upregulation of its protein levels. Therefore, HBx variants containing Ser-101 induced p53-dependent activation of PA28γ expression in human hepatoma cells. The elevated PA28γ levels upregulated HBx levels through the inhibition of seven in absentia homologue 1-dependent proteasomal degradation. The self-amplifying ability of HBx variants containing Ser-101 via a positive feedback loop involving p53 and PA28γ was accurately reproduced in both a 1.2-mer HBV replicon and in vitro HBV infection systems, which also provided evidence for the stimulation of HBV replication by these HBx variants. In conclusion, the ability of HBx to upregulate PA28γ levels via p53 activation, in a Ser-101-dependent pathway, is critical for the stimulation of HBV replication.
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Affiliation(s)
- Hyerin Jeong
- Department of Microbiology, College of Natural Science, Pusan National University, Busan 46241, Republic of Korea
| | - Sungkyung Cha
- Department of Microbiology, College of Natural Science, Pusan National University, Busan 46241, Republic of Korea
| | - Kyung Lib Jang
- Department of Microbiology, College of Natural Science, Pusan National University, Busan 46241, Republic of Korea
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Elizalde MM, Speroni M, Campos RH, Flichman DM. Hepatitis B Virus X Gene Differentially Modulates Subgenotype F1b and F4 Replication. Viruses 2019; 11:v11070655. [PMID: 31323763 PMCID: PMC6669721 DOI: 10.3390/v11070655] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2019] [Revised: 07/12/2019] [Accepted: 07/16/2019] [Indexed: 12/18/2022] Open
Abstract
Hepatitis B virus (HBV) is classified into ten genotypes and numerous subgenotypes (sgt). In particular, sgt F1b and sgt F4, native of Latin America, have been associated with differences in clinical and virological characteristics. Hepatitis B virus X protein (HBx) is a multifunctional regulatory protein associated with the modulation of viral transcription and replication. In this work, we analyzed the role of the X gene and the encoded X protein in sgtF1b and sgtF4 replication. Transfection with HBx deficient genomes revealed remarkable differences in the replicative capacity of sgtF1b and sgtF4 mutants. The silencing of HBx increased sgtF1b X(-) transcription and replication by more than 2.5 fold compared to the wild type variant, while it decreased sgtF4 X(-) transcription and replication by more than 3 fold. Trans-complementation of HBx restore sgtF1b and sgtF4 wild type transcription and replication levels. In addition, transfection with chimeric variants, carrying wild type (F1b/XF4 and F4/XF1b) or mutated (F1b/X(-)F4 and F4/X(-)F1b) X gene of one sgt in the backbone of the other sgt, showed that the nucleotide sequence of the X gene, that includes regulatory elements that modulate pgRNA transcription, was responsible for the disparity observed between sgtF1b X(-) and sgtF4 X(-). These results showed that sgtF1b and sgtF4 X gene play a central role in regulating HBV transcription and replication, which eventually lead to a common purpose, to reach wild type replication levels of sgtF1b and sgtF4 viruses.
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Affiliation(s)
- María Mercedes Elizalde
- Cátedra de Virología, Departamento de Microbiología, Inmunología, Biotecnología y Genética, Facultad de Farmacia y Bioquímica, Universidad de Buenos Aires, Junín 956, Buenos Aires 1113, Argentina.
- Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Buenos Aires 1425, Argentina.
| | - Micaela Speroni
- Cátedra de Virología, Departamento de Microbiología, Inmunología, Biotecnología y Genética, Facultad de Farmacia y Bioquímica, Universidad de Buenos Aires, Junín 956, Buenos Aires 1113, Argentina
- Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Buenos Aires 1425, Argentina
| | - Rodolfo Héctor Campos
- Cátedra de Virología, Departamento de Microbiología, Inmunología, Biotecnología y Genética, Facultad de Farmacia y Bioquímica, Universidad de Buenos Aires, Junín 956, Buenos Aires 1113, Argentina
- Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Buenos Aires 1425, Argentina
| | - Diego Martín Flichman
- Cátedra de Virología, Departamento de Microbiología, Inmunología, Biotecnología y Genética, Facultad de Farmacia y Bioquímica, Universidad de Buenos Aires, Junín 956, Buenos Aires 1113, Argentina
- Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Buenos Aires 1425, Argentina
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Mani M, Vijayaraghavan S, Sarangan G, Barani R, Abraham P, Srikanth P. Hepatitis B virus X protein: The X factor in chronic hepatitis B virus disease progression. Indian J Med Microbiol 2019; 37:387-392. [PMID: 32003338 DOI: 10.4103/ijmm.ijmm_19_421] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Introduction Hepatitis B virus (HBV) is the most common aetiological factor causing hepatocellular carcinoma (HCC). HBx gene plays an enigmatic role in HBV-related HCC. In this study we have analysed amino acid substitutions in HBx from HBV-infected individuals of different clinical stages. Materials and Methods HBV-infected individuals (n = 93) were recruited in the study. DNA was extracted from plasma, amplified, and DNA sequencing was performed using specific primers targeting HBx gene (540 bp). Results Among the study participants, 57% had chronic HBV infection, 30% had chronic liver disease (CLD) and 13% had HBV related HCC. Genotypes such as D1, D2, D3, A1, C2 and B2 were identified of which genotype D2 was predominant (78%). HBxC-terminal deletion was observed in four hepatitis B e antigen (HBeAg) negative participants with CLD. The frequency of aminoacid substitution in proapoptotic domain was higher in HBeAg negative participants including I127V (34%), K130M (34%), V131I (40%). The frequency of double mutation (K130M+V131I) and triple mutation (I127V+K130M+V131I) were found to be higher (32% and 36%) in HBeAg negative participants. Also, we identified L5M substitution (4.3%) in HBeAg positive participants with advanced liver disease. Conclusion In HBx gene, aminoacid substitutions at positions 127, 130, 131 are associated with poor expression of HBeAg. We suggest screening for HBx aminoacid substitutions especially in patients with HBeAg negative chronic HBV infection to predict the clinical outcome and enable early treatment to prevent disease progression.
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Affiliation(s)
- Monika Mani
- Department of Microbiology, Sri Ramachandra Institute of Higher Education and Research, Chennai, Tamil Nadu, India
| | - Shanthi Vijayaraghavan
- Department of Medical Gastroenterology, Sri Ramachandra Institute of Higher Education and Research, Chennai, Tamil Nadu, India
| | - Gopalsamy Sarangan
- Department of Microbiology, Sri Ramachandra Institute of Higher Education and Research, Chennai, Tamil Nadu, India
| | - Ramya Barani
- Department of Microbiology, Sri Ramachandra Institute of Higher Education and Research, Chennai, Tamil Nadu, India
| | - Priya Abraham
- Department of Clinical Virology, Christian Medical College, Vellore, Tamil Nadu, India
| | - Padma Srikanth
- Department of Microbiology, Sri Ramachandra Institute of Higher Education and Research, Chennai, Tamil Nadu, India
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Peroxiredoxin 1, a Novel HBx-Interacting Protein, Interacts with Exosome Component 5 and Negatively Regulates Hepatitis B Virus (HBV) Propagation through Degradation of HBV RNA. J Virol 2019; 93:JVI.02203-18. [PMID: 30567989 DOI: 10.1128/jvi.02203-18] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2018] [Accepted: 12/12/2018] [Indexed: 12/20/2022] Open
Abstract
Hepatitis B virus (HBV) infection is a major risk factor for the development of chronic liver diseases, including cirrhosis and hepatocellular carcinoma (HCC). A growing body of evidence suggests that HBV X protein (HBx) plays a crucial role in viral replication and HCC development. Here, we identified peroxiredoxin 1 (Prdx1), a cellular hydrogen peroxide scavenger, as a novel HBx-interacting protein. Coimmunoprecipitation analysis coupled with site-directed mutagenesis revealed that the region from amino acids 17 to 20 of the HBx, particularly HBx Cys17, is responsible for the interaction with Prdx1. Knockdown of Prdx1 by siRNA significantly increased the levels of intracellular HBV RNA, HBV antigens, and extracellular HBV DNA, whereas knockdown of Prdx1 did not increase the activities of HBV core, enhancer I (Enh1)/X, preS1, and preS2/S promoters. Kinetic analysis of HBV RNA showed that knockdown of Prdx1 inhibited HBV RNA decay, suggesting that Prdx1 reduces HBV RNA levels posttranscriptionally. The RNA coimmunoprecipitation assay revealed that Prdx1 interacted with HBV RNA. The exosome component 5 (Exosc5), a member of the RNA exosome complexes, was coimmunoprecipitated with Prdx1, suggesting its role in regulation of HBV RNA stability. Taken together, these results suggest that Prdx1 and Exosc5 play crucial roles in host defense mechanisms against HBV infection.IMPORTANCE Hepatitis B virus (HBV) infection is a major global health problem. HBx plays important roles in HBV replication and viral carcinogenesis through its interaction with host factors. In this study, we identified Prdx1 as a novel HBx-binding protein. We provide evidence suggesting that Prdx1 promotes HBV RNA decay through interaction with HBV RNA and Exosc5, leading to downregulation of HBV RNA. These results suggest that Prdx1 negatively regulates HBV propagation. Our findings may shed new light on the roles of Prdx1 and Exosc5 in host defense mechanisms in HBV infection.
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Lee H, Jeong H, Lee SY, Kim SS, Jang KL. Hepatitis B Virus X Protein Stimulates Virus Replication Via DNA Methylation of the C-1619 in Covalently Closed Circular DNA. Mol Cells 2019; 42:67-78. [PMID: 30518174 PMCID: PMC6354056 DOI: 10.14348/molcells.2018.0255] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2018] [Revised: 11/22/2018] [Accepted: 11/26/2018] [Indexed: 02/06/2023] Open
Abstract
Methylation of HBV cccDNA has been detected in vivo and in vitro; however, the mechanism and its effects on HBV replication remain unclear. HBx derived from a 1.2-mer HBV replicon upregulated protein levels and enzyme activities of DNA methyltransferase 1 (DNMT1), 3a, and 3b, resulting in methylation of the negative regulatory region (NRE) in cccDNA, while none of these effects were observed with an HBx-null mutant. The HBx-positive HBV cccDNA expressed higher levels of HBc and produced about 4-fold higher levels of HBV particles than those from the HBx-null counterpart. For these effects, HBx interrupted the action of NRE binding protein via methylation of the C-1619 within NRE, resulting in activation of the core promoter. Treatment with 5-Aza-2'dC or DNMT1 knock-down drastically impaired the ability of HBx to activate the core promoter and stimulate HBV replication in 1.2-mer HBV replicon and in vitro infection systems, indicating the positive role of HBx-mediated cccDNA methylation in HBV replication.
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Affiliation(s)
- Hyehyeon Lee
- Department of Microbiology, College of Natural Science, Pusan National University, Busan 46241,
Korea
| | - Hyerin Jeong
- Department of Microbiology, College of Natural Science, Pusan National University, Busan 46241,
Korea
| | - Sun Young Lee
- Department of Microbiology, College of Natural Science, Pusan National University, Busan 46241,
Korea
| | - Soo Shin Kim
- Department of Microbiology, College of Natural Science, Pusan National University, Busan 46241,
Korea
| | - Kyung Lib Jang
- Department of Microbiology, College of Natural Science, Pusan National University, Busan 46241,
Korea
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45
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Tang X, Yan L, Li H, Du L, Shi Y, Huang F, Tang H. Increased expression of phosphoenolpyruvate carboxykinase cytoplasmic isoform by hepatitis B virus X protein affects hepatitis B virus replication. J Med Virol 2018; 91:258-264. [PMID: 30168585 DOI: 10.1002/jmv.25300] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2018] [Accepted: 08/09/2018] [Indexed: 02/05/2023]
Abstract
Hepatitis B virus X protein (HBx) can stimulate the transcription of phosphoenolpyruvate carboxykinase (PEPCK), a rate-determining enzyme in gluconeogenic pathway. Two isoforms of PEPCK exist, a cytoplasmic form (PCK1) and a mitochondrial isoform (PCK2). The current study investigated the direct effect of HBx-stimulated PEPCK on hepatitis B virus (HBV) replication. We showed that PCK1 rather than PCK2 was upregulated by HBx. We also demonstrated that overexpression of PCK1 decreased HBV replication, whereas inhibition of PCK1-enhanced HBV replication. Furthermore, we found overexpression of PCK1 led to reduced expression of peroxisome proliferator-activated receptor-coactivator 1α (PGC-1α) and peroxisome proliferator-activated receptor γ (PPAR-γ), whereas knocking down PCK1 resulted in an increased expression of PGC-1α and PPAR-γ. When PPAR-γ was inhibited, knocking down PCK1 could not induce the apparent enhanced HBV replication. Our data suggested that PCK1 induced by HBx led to decreased HBV replication through the downregulation of PGC-1α and PPAR-γ. Thus, our study demonstrates a negative-feedback loop involving PCK1 and HBV may provide a balanced cell environment for HBV persistent infection.
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Affiliation(s)
- Xiaoqiong Tang
- Center of Infectious Diseases, West China Hospital of Sichuan University, Chengdu, China
| | - Libo Yan
- Center of Infectious Diseases, West China Hospital of Sichuan University, Chengdu, China
| | - Hong Li
- Center of Infectious Diseases, West China Hospital of Sichuan University, Chengdu, China
| | - Lingyao Du
- Center of Infectious Diseases, West China Hospital of Sichuan University, Chengdu, China
| | - Ying Shi
- Center of Infectious Diseases, West China Hospital of Sichuan University, Chengdu, China
| | - Feijun Huang
- Department of Forensic Pathology, Medical School of Basic and Forensic Sciences, Sichuan University, Chengdu, China
| | - Hong Tang
- Center of Infectious Diseases, West China Hospital of Sichuan University, Chengdu, China
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Tan G, Xu F, Song H, Yuan Y, Xiao Q, Ma F, Qin FXF, Cheng G. Identification of TRIM14 as a Type I IFN-Stimulated Gene Controlling Hepatitis B Virus Replication by Targeting HBx. Front Immunol 2018; 9:1872. [PMID: 30150992 PMCID: PMC6100580 DOI: 10.3389/fimmu.2018.01872] [Citation(s) in RCA: 40] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2018] [Accepted: 07/30/2018] [Indexed: 12/28/2022] Open
Abstract
Hepatitis B virus (HBV) remains a major cause of hepatic disease that threatens human health worldwide. Type I IFN (IFN-I) therapy is an important therapeutic option for HBV patients. The antiviral effect of IFN is mainly mediated via upregulation of the expressions of the downstream IFN-stimulated genes. However, the mechanisms by which IFN induces ISG production and inhibits HBV replication are yet to be clarified. TRIM14 was recently reported as a key molecule in the IFN-signaling pathway that regulates IFN production in response to viral infection. In this study, we sought to understand the mechanisms by which IFN restricts HBV replication. We confirmed that TRIM14 is an ISG in the hepatic cells, and that the pattern-recognition receptor ligands polyI:C and polydAdT induce TRIM14 dependent on IFN-I production. In addition, IFN-I-activated STAT1 (but not STAT3) directly bound to the TRIM14 promoter and mediated the induction of TRIM14. Interestingly, TRIM14 played an important role in IFN-I-mediated inhibition of HBV, and the TRIM14 SPRY domain interacted with the C-terminal of HBx, which might block the role of HBx in facilitating HBV replication by inhibiting the formation of the Smc-HBx–DDB1 complex. Thus, our study clearly demonstrates that TRIM14 is a STAT1-dependent ISG, and that the IFN-I–TRIM14–HBx axis shows an alternative way to understand the mechanism by which IFN-I inhibits virus replication.
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Affiliation(s)
- Guangyun Tan
- Department of Immunology, Institute of Translational Medicine, The First Hospital of Jilin University, Changchun, China
| | - Fengchao Xu
- Department of Immunology, Institute of Translational Medicine, The First Hospital of Jilin University, Changchun, China
| | - Hongxiao Song
- Department of Immunology, Institute of Translational Medicine, The First Hospital of Jilin University, Changchun, China
| | - Ye Yuan
- Department of Medicine Laboratory, The First Hospital of Jilin University, Changchun, China
| | - Qingfei Xiao
- Department of Nephrology, The First Hospital, Jilin University, Changchun, China
| | - Feng Ma
- Suzhou Institute of Systems Medicine, Suzhou, China
| | | | - Genhong Cheng
- Department of Immunology, Institute of Translational Medicine, The First Hospital of Jilin University, Changchun, China.,Suzhou Institute of Systems Medicine, Suzhou, China.,Department of Microbiology, Immunology and Molecular Genetics, University of California, Los Angeles, CA, United States
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Multiple Functions of Cellular FLIP Are Essential for Replication of Hepatitis B Virus. J Virol 2018; 92:JVI.00339-18. [PMID: 29875248 DOI: 10.1128/jvi.00339-18] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2018] [Accepted: 05/24/2018] [Indexed: 02/06/2023] Open
Abstract
Hepatitis B virus (HBV) infection is a leading cause of liver diseases; however, the host factors which facilitate the replication and persistence of HBV are largely unidentified. Cellular FLICE inhibitory protein (c-FLIP) is a typical antiapoptotic protein. In many cases of liver diseases, the expression level of c-FLIP is altered, which affects the fate of hepatocytes. We previously found that c-FLIP and its cleaved form interact with HBV X protein (HBx), which is essential for HBV replication, and regulate diverse cellular signals. In this study, we investigated the role of endogenous c-FLIP in HBV replication and its underlying mechanisms. The knockdown of endogenous c-FLIP revealed that this protein regulates HBV replication through two different mechanisms. (i) c-FLIP interacts with HBx and protects it from ubiquitin-dependent degradation. The N-terminal DED1 domain of c-FLIP is required for HBx stabilization. (ii) c-FLIP regulates the expression or stability of hepatocyte nuclear factors (HNFs), which have critical roles in HBV transcription and maintenance of hepatocytes. c-FLIP regulates the stability of HNFs through physical interactions. We verified our findings in three HBV infection systems: HepG2-NTCP cells, differentiated HepaRG cells, and primary human hepatocytes. In conclusion, our results identify c-FLIP as an essential factor in HBV replication. c-FLIP regulates viral replication through its multiple effects on viral and host proteins that have critical roles in HBV replication.IMPORTANCE Although the chronic hepatitis B virus (HBV) infection still poses a major health concern, the host factors which are required for the replication of HBV are largely uncharacterized. Our studies identify cellular FLICE inhibitory protein (c-FLIP) as an essential factor in HBV replication. We found the dual roles of c-FLIP in regulation of HBV replication: c-FLIP interacts with HBx and enhances its stability and regulates the expression or stability of hepatocyte nuclear factors which are essential for transcription of HBV genome. Our findings may provide a new target for intervention in persistent HBV infection.
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48
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IL-1β/ATF3-mediated induction of Ski2 expression enhances hepatitis B virus x mRNA degradation. Biochem Biophys Res Commun 2018; 503:1854-1860. [PMID: 30055801 DOI: 10.1016/j.bbrc.2018.07.126] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2018] [Accepted: 07/24/2018] [Indexed: 12/17/2022]
Abstract
Hepatitis B virus (HBV) -x protein is a transcriptional regulator required for the HBV life cycle. HBx also induces complications in the host such as hepatocellular carcinoma. We previously showed that HBx mRNA is degraded by the Ski2/RNA exosome complex. In the present study, we report the regulation of this system through the control of Ski2 expression. We identified interleukin (IL) -1β as an inducer of expression from the Ski2 promoter. IL-1β induced the expression of ATF3 transcription factor, which in turn binds to cyclic AMP-responsive element sequence in the Ski2 promoter and is responsible for Ski2 promoter induction by IL-1β. We previously reported that Ski2 expression increases HBx mRNA degradation; consistent with those data, we showed here that HBx mRNA is degraded in response to IL-1β treatment. Interestingly, HBx also significantly induced Ski2 expression. To our knowledge, this is the first report to show activation of the Ski2/RNA exosome complex by both the host and HBV. Understanding the regulation of the Ski2/RNA exosome system is expected to facilitate prevention of HBx-mediated complications through targeting the posttranscriptional degradation of HBx mRNA; and will also help shedding a light on the role of RNA decay systems in inflammation.
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Wu IC, Liu WC, Chang TT. Applications of next-generation sequencing analysis for the detection of hepatocellular carcinoma-associated hepatitis B virus mutations. J Biomed Sci 2018; 25:51. [PMID: 29859540 PMCID: PMC5984823 DOI: 10.1186/s12929-018-0442-4] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2018] [Accepted: 04/30/2018] [Indexed: 02/06/2023] Open
Abstract
BACKGROUND Next-generation sequencing (NGS) is a powerful and high-throughput method for the detection of viral mutations. This article provides a brief overview about optimization of NGS analysis for hepatocellular carcinoma (HCC)-associated hepatitis B virus (HBV) mutations, and hepatocarcinogenesis of relevant mutations. MAIN BODY For the application of NGS analysis in the genome of HBV, four noteworthy steps were discovered in testing. First, a sample-specific reference sequence was the most effective mapping reference for NGS. Second, elongating the end of reference sequence improved mapping performance at the end of the genome. Third, resetting the origin of mapping reference sequence could probed deletion mutations and variants at a certain location with common mutations. Fourth, using a platform-specific cut-off value to distinguish authentic minority variants from technical artifacts was found to be highly effective. One hundred and sixty-seven HBV single nucleotide variants (SNVs) were found to be studied previously through a systematic literature review, and 12 SNVs were determined to be associated with HCC by meta-analysis. From comprehensive research using a HBV genome-wide NGS analysis, 60 NGS-defined HCC-associated SNVs with their pathogenic frequencies were identified, with 19 reported previously. All the 12 HCC-associated SNVs proved by meta-analysis were confirmed by NGS analysis, except for C1766T and T1768A which were mainly expressed in genotypes A and D, but including the subgroup analysis of A1762T. In the 41 novel NGS-defined HCC-associated SNVs, 31.7% (13/41) had cut-off values of SNV frequency lower than 20%. This showed that NGS could be used to detect HCC-associated SNVs with low SNV frequency. Most SNV II (the minor strains in the majority of non-HCC patients) had either low (< 20%) or high (> 80%) SNV frequencies in HCC patients, a characteristic U-shaped distribution pattern. The cut-off values of SNV frequency for HCC-associated SNVs represent their pathogenic frequencies. The pathogenic frequencies of HCC-associated SNV II also showed a U-shaped distribution. Hepatocarcinogenesis induced by HBV mutated proteins through cellular pathways was reviewed. CONCLUSION NGS analysis is useful to discover novel HCC-associated HBV SNVs, especially those with low SNV frequency. The hepatocarcinogenetic mechanisms of novel HCC-associated HBV SNVs defined by NGS analysis deserve further investigation.
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Affiliation(s)
- I-Chin Wu
- Department of Internal Medicine, National Cheng Kung University Hospital, College of Medicine, National Cheng Kung University, 138 Sheng-Li Road, Tainan, 70403, Taiwan, Republic of China.,Infectious Disease and Signaling Research Center, National Cheng Kung University, Tainan, Taiwan, Republic of China
| | - Wen-Chun Liu
- Department of Internal Medicine, National Cheng Kung University Hospital, College of Medicine, National Cheng Kung University, 138 Sheng-Li Road, Tainan, 70403, Taiwan, Republic of China.,Infectious Disease and Signaling Research Center, National Cheng Kung University, Tainan, Taiwan, Republic of China
| | - Ting-Tsung Chang
- Department of Internal Medicine, National Cheng Kung University Hospital, College of Medicine, National Cheng Kung University, 138 Sheng-Li Road, Tainan, 70403, Taiwan, Republic of China.
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50
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Kumar R, Khandelwal N, Thachamvally R, Tripathi BN, Barua S, Kashyap SK, Maherchandani S, Kumar N. Role of MAPK/MNK1 signaling in virus replication. Virus Res 2018; 253:48-61. [PMID: 29864503 PMCID: PMC7114592 DOI: 10.1016/j.virusres.2018.05.028] [Citation(s) in RCA: 76] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2018] [Revised: 04/16/2018] [Accepted: 05/31/2018] [Indexed: 12/23/2022]
Abstract
Viruses are known to exploit cellular signaling pathways. MAPK is a major cell signaling pathway activated by diverse group of viruses. MNK1 regulates both cap-dependent and IRES-mediated mRNA translation. This review discuss the role of MAPK, particularly the role of MNK1 in virus replication.
Viruses are obligate intracellular parasites; they heavily depend on the host cell machinery to effectively replicate and produce new progeny virus particles. Following viral infection, diverse cell signaling pathways are initiated by the cells, with the major goal of establishing an antiviral state. However, viruses have been shown to exploit cellular signaling pathways for their own effective replication. Genome-wide siRNA screens have also identified numerous host factors that either support (proviral) or inhibit (antiviral) virus replication. Some of the host factors might be dispensable for the host but may be critical for virus replication; therefore such cellular factors may serve as targets for development of antiviral therapeutics. Mitogen activated protein kinase (MAPK) is a major cell signaling pathway that is known to be activated by diverse group of viruses. MAPK interacting kinase 1 (MNK1) has been shown to regulate both cap-dependent and internal ribosomal entry sites (IRES)-mediated mRNA translation. In this review we have discuss the role of MAPK in virus replication, particularly the role of MNK1 in replication and translation of viral genome.
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Affiliation(s)
- Ram Kumar
- Virology Laboratory, National Centre for Veterinary Type Cultures, ICAR-National Research Centre on Equines, Hisar, Haryana 125001, India; Department of Veterinary Microbiology and Biotechnology, Rajasthan University of Veterinary and Animal Sciences, Bikaner, Rajasthan 334001, India
| | - Nitin Khandelwal
- Virology Laboratory, National Centre for Veterinary Type Cultures, ICAR-National Research Centre on Equines, Hisar, Haryana 125001, India
| | - Riyesh Thachamvally
- Virology Laboratory, National Centre for Veterinary Type Cultures, ICAR-National Research Centre on Equines, Hisar, Haryana 125001, India
| | - Bhupendra Nath Tripathi
- Virology Laboratory, National Centre for Veterinary Type Cultures, ICAR-National Research Centre on Equines, Hisar, Haryana 125001, India
| | - Sanjay Barua
- Virology Laboratory, National Centre for Veterinary Type Cultures, ICAR-National Research Centre on Equines, Hisar, Haryana 125001, India
| | - Sudhir Kumar Kashyap
- Department of Veterinary Microbiology and Biotechnology, Rajasthan University of Veterinary and Animal Sciences, Bikaner, Rajasthan 334001, India
| | - Sunil Maherchandani
- Department of Veterinary Microbiology and Biotechnology, Rajasthan University of Veterinary and Animal Sciences, Bikaner, Rajasthan 334001, India
| | - Naveen Kumar
- Virology Laboratory, National Centre for Veterinary Type Cultures, ICAR-National Research Centre on Equines, Hisar, Haryana 125001, India.
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