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Cao X, Chen Y, Chen Y, Jiang M. The Role of Tripartite Motif Family Proteins in Chronic Liver Diseases: Molecular Mechanisms and Therapeutic Potential. Biomolecules 2024; 14:1038. [PMID: 39199424 PMCID: PMC11352684 DOI: 10.3390/biom14081038] [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: 07/11/2024] [Revised: 08/20/2024] [Accepted: 08/20/2024] [Indexed: 09/01/2024] Open
Abstract
The worldwide impact of liver diseases is increasing steadily, with a consistent upswing evidenced in incidence and mortality rates. Chronic liver diseases (CLDs) refer to the liver function's progressive deterioration exceeding six months, which includes abnormal clotting factors, detoxification failure, and hepatic cholestasis. The most common etiologies of CLDs are mainly composed of chronic viral hepatitis, MAFLD/MASH, alcoholic liver disease, and genetic factors, which induce inflammation and harm to the liver, ultimately resulting in cirrhosis, the irreversible final stage of CLDs. The latest research has shown that tripartite motif family proteins (TRIMs) function as E3 ligases, which participate in the progression of CLDs by regulating gene and protein expression levels through post-translational modification. In this review, our objective is to clarify the molecular mechanisms and potential therapeutic targets of TRIMs in CLDs and provide insights for therapy guidelines and future research.
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Affiliation(s)
- Xiwen Cao
- The Queen Mary School, Jiangxi Medical College, Nanchang University, 999 Xuefu Road, Nanchang 330031, China;
| | - Yinni Chen
- The National Engineering Research Center for Bioengineering Drugs and the Technologies, Institute of Translational Medicine, Jiangxi Medical College, Nanchang University, 999 Xuefu Road, Nanchang 330031, China;
| | - Yuanli Chen
- Key Laboratory of Major Metabolic Diseases, Nutritional Regulation of Anhui Department of Education, College of Food and Biological Engineering, Hefei University of Technology, Hefei 230002, China;
| | - Meixiu Jiang
- The National Engineering Research Center for Bioengineering Drugs and the Technologies, Institute of Translational Medicine, Jiangxi Medical College, Nanchang University, 999 Xuefu Road, Nanchang 330031, China;
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2
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Yoon H, Jang KL. Hydrogen Peroxide Inhibits Hepatitis C Virus Replication by Downregulating Hepatitis C Virus Core Levels through E6-Associated Protein-Mediated Proteasomal Degradation. Cells 2023; 13:62. [PMID: 38201266 PMCID: PMC10778395 DOI: 10.3390/cells13010062] [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: 11/10/2023] [Revised: 12/22/2023] [Accepted: 12/26/2023] [Indexed: 01/12/2024] Open
Abstract
Hepatitis C virus (HCV) is constantly exposed to considerable oxidative stress, characterized by elevated levels of reactive oxygen species, including hydrogen peroxide (H2O2), during acute and chronic infection in the hepatocytes of patients. However, the effect of oxidative stress on HCV replication is largely unknown. In the present study, we demonstrated that H2O2 downregulated HCV Core levels to inhibit HCV replication. For this purpose, H2O2 upregulated p53 levels, resulting in the downregulation of both the protein and enzyme activity levels of DNA methyltransferase 1 (DNMT1), DNMT3a, and DNMT3b, and activated the expression of E6-associated protein (E6AP) through promoter hypomethylation in the presence of HCV Core. E6AP, an E3 ligase, induced the ubiquitin-dependent proteasomal degradation of HCV Core in a p53-dependent manner. The inhibitory effect of H2O2 on HCV replication was almost completely nullified either by treatment with a representative antioxidant, N-acetyl-L-cysteine, or by knockdown of p53 or E6AP using a specific short hairpin RNA, confirming the roles of p53 and E6AP in the inhibition of HCV replication by H2O2. This study provides insights into the mechanisms that regulate HCV 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;
| | - 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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3
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Park JM, Yoon H, Jeong Y, Jang KL. Tumor suppressor p53 inhibits hepatitis C virus replication by inducing E6AP-mediated proteasomal degradation of the viral core protein. FEBS Lett 2022; 596:2525-2537. [PMID: 35918185 DOI: 10.1002/1873-3468.14461] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2022] [Revised: 06/24/2022] [Accepted: 07/09/2022] [Indexed: 11/08/2022]
Abstract
The tumor suppressor p53 has been implicated in the host defense system against hepatitis C virus (HCV) infection, although the detailed mechanism remains unknown. Here, we found that p53 inhibits HCV replication by downregulating HCV Core protein levels in human hepatoma cells. For this effect, p53 potentiated the role of E6-associated protein (E6AP) as an E3 ligase to induce ubiquitination and proteasomal degradation of HCV Core. Specifically, p53 facilitated the binding of E6AP to HCV Core through direct interactions with the two proteins. In addition, E6AP failed to induce ubiquitination of HCV Core in the absence of p53, suggesting that p53 increases the E3 ligase activity of E6AP in a triple complex consisting of p53, E6AP, and HCV Core.
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Affiliation(s)
- Ji-Min Park
- 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
| | - Yuna Jeong
- 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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4
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Miyamoto D, Takeuchi K, Chihara K, Fujieda S, Sada K. Protein tyrosine kinase Abl promotes hepatitis C virus particle assembly via interaction with viral substrate activator NS5A. J Biol Chem 2022; 298:101804. [PMID: 35257746 PMCID: PMC8980994 DOI: 10.1016/j.jbc.2022.101804] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2021] [Revised: 02/26/2022] [Accepted: 02/28/2022] [Indexed: 11/30/2022] Open
Abstract
Previously, we reported that knockdown of Abl protein tyrosine kinase by shRNA or pharmacological inhibition suppresses particle assembly of J6/JFH1 strain–derived hepatitis C virus (HCV) in Huh-7.5 cells. However, the detailed mechanism by which Abl regulates HCV replication remained unclear. In this study, we established Abl-deficient (Abl−) cells through genome editing and compared HCV production between Abl− cells expressing WT or kinase-dead Abl and parental Huh-7.5 cells. Our findings revealed that Abl expression was not required from the stages of virus attachment and entry to viral gene expression; however, the kinase activity of Abl was necessary for the assembly of HCV particles. Reconstitution experiments using human embryonic kidney 293T cells revealed that phosphorylation of Tyr412 in the activation loop of Abl was enhanced by coexpression with the viral nonstructural protein 5A (NS5A) and was abrogated by the substitution of NS5A Tyr330 with Phe (Y330F), suggesting that NS5A functions as a substrate activator of Abl. Abl–NS5A association was also attenuated by the Y330F mutation of NS5A or the kinase-dead Abl, and Abl Tyr412 phosphorylation was not enhanced by NS5A bearing a mutation disabling homodimerization, although the association of Abl with NS5A was still observed. Taken together, these results demonstrate that Abl forms a phosphorylation-dependent complex with dimeric NS5A necessary for viral particle assembly, but that Abl is capable of complex formation with monomeric NS5A regardless of tyrosine phosphorylation. Our findings provide the foundation of a molecular basis for a new hepatitis C treatment strategy using Abl inhibitors.
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Affiliation(s)
- Daisuke Miyamoto
- Department of Otorhinolaryngology Head & Neck Surgery, Faculty of Medical Sciences, University of Fukui, Fukui, Japan; Department of Genome Science and Microbiology, Faculty of Medical Sciences, University of Fukui, Fukui, Japan
| | - Kenji Takeuchi
- Department of Genome Science and Microbiology, Faculty of Medical Sciences, University of Fukui, Fukui, Japan; Organization for Life Science Advancement Programs, University of Fukui, Fukui, Japan
| | - Kazuyasu Chihara
- Department of Genome Science and Microbiology, Faculty of Medical Sciences, University of Fukui, Fukui, Japan; Organization for Life Science Advancement Programs, University of Fukui, Fukui, Japan
| | - Shigeharu Fujieda
- Department of Otorhinolaryngology Head & Neck Surgery, Faculty of Medical Sciences, University of Fukui, Fukui, Japan; Organization for Life Science Advancement Programs, University of Fukui, Fukui, Japan
| | - Kiyonao Sada
- Department of Genome Science and Microbiology, Faculty of Medical Sciences, University of Fukui, Fukui, Japan; Organization for Life Science Advancement Programs, University of Fukui, Fukui, Japan.
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5
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Breitinger U, Farag NS, Ali NKM, Ahmed M, El-Azizi MA, Breitinger HG. Cell viability assay as a tool to study activity and inhibition of hepatitis C p7 channels. J Gen Virol 2021; 102. [PMID: 33709903 DOI: 10.1099/jgv.0.001571] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
The p7 viroporin of the hepatitis C virus (HCV) forms an intracellular proton-conducting transmembrane channel in virus-infected cells, shunting the pH of intracellular compartments and thus helping virus assembly and release. This activity is essential for virus infectivity, making viroporins an attractive target for drug development. The protein sequence and drug sensitivity of p7 vary between the seven major genotypes of the hepatitis C virus, but the essential channel activity is preserved. Here, we investigated the effect of several inhibitors on recombinant HCV p7 channels corresponding to genotypes 1a-b, 2a-b, 3a and 4a using patch-clamp electrophysiology and cell-based assays. We established a 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT)-based cell viability assay for recombinant p7 expressed in HEK293 cells to assess channel activity and its sensitivity to inhibitors. The results from the cell viability assay were consistent with control measurements using established assays of haemadsorption and intracellular pH, and agreed with data from patch-clamp electrophysiology. Hexamethylene amiloride (HMA) was the most potent inhibitor of p7 activity, but possessed cytotoxic activity at higher concentrations. Rimantadine was active against p7 of all genotypes, while amantadine activity was genotype-dependent. The alkyl-chain iminosugars NB-DNJ, NN-DNJ and NN-DGJ were tested and their activity was found to be genotype-specific. In the current study, we introduce cell viability assays as a rapid and cost-efficient technique to assess viroporin activity and identify channel inhibitors as potential novel antiviral drugs.
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Affiliation(s)
- Ulrike Breitinger
- Department of Biochemistry, German University in Cairo, New Cairo, Egypt
| | - Noha S Farag
- Department of Microbiology and Immunology, German University in Cairo, New Cairo, Egypt
| | - Nourhan K M Ali
- Department of Biochemistry, German University in Cairo, New Cairo, Egypt
| | - Marwa Ahmed
- Present address: Institute of Biochemistry and Biophysics Friedrich-Schiller-University Jena, Hans-Knöll-Str. 2, D-07745, Jena, Germany.,Department of Biochemistry, German University in Cairo, New Cairo, Egypt
| | - Mohamed A El-Azizi
- Department of Microbiology and Immunology, German University in Cairo, New Cairo, Egypt
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Hepatitis C virus core protein activates proteasomal activator 28 gamma to downregulate p16 levels via ubiquitin-independent proteasomal degradation. Heliyon 2021; 7:e06134. [PMID: 33553768 PMCID: PMC7851347 DOI: 10.1016/j.heliyon.2021.e06134] [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] [Subscribe] [Scholar Register] [Received: 11/02/2020] [Revised: 12/22/2020] [Accepted: 01/25/2021] [Indexed: 12/29/2022] Open
Abstract
Proteasomal activator 28 gamma (PA28γ), an essential constituent of the 20S proteasome, is frequently overexpressed in hepatocellular carcinoma. Hepatitis C virus (HCV) core protein is recently known to activate PA28γ expression in human hepatocytes via upregulation of p53 levels; however, its role in HCV tumorigenesis remains unknown. Here, we found that HCV core-activated PA28γ downregulates p16 levels via ubiquitin-independent proteasomal degradation. As a result, HCV core protein activated the Rb-E2F pathway to stimulate cell cycle progression from G1 to S phase, resulting in an increase in cell proliferation. The potential of HCV core protein to induce these effects was almost completely abolished by either PA28γ knockdown or p16 overexpression, confirming the role of the PA28γ-mediated p16 degradation in HCV tumorigenesis.
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Liao Y, Luo D, Peng K, Zeng Y. Cyclophilin A: a key player for etiological agent infection. Appl Microbiol Biotechnol 2021; 105:1365-1377. [PMID: 33492451 PMCID: PMC7829623 DOI: 10.1007/s00253-021-11115-2] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2020] [Revised: 01/07/2021] [Accepted: 01/13/2021] [Indexed: 12/13/2022]
Abstract
Abstract Cyclophilin A (CypA), a key member of the immunophilin family, is the most abundantly expressed isozyme of the 18 known human cyclophilins. Besides acting as an intracellular receptor for cyclosporine A, CypA plays a vital role in microorganismal infections, cardiovascular diseases, liver diseases, kidney diseases, neurodegeneration, cancer, rheumatoid arthritis, periodontitis, sepsis, asthma, and aging. This review focuses on the pivotal roles of CypA in the infection of etiological agents, which manifests mainly in promoting or inhibiting viral replication based on the host cell type and viral species. CypA can interact with viral proteins and thus regulate the replication cycle of the virus. CypA is involved in pathogenic bacterial infections by regulating the formation of host actin skeleton or membrane translocation of bacterial toxins, or mediated the adhesion of Mycoplasma genitalium during the infection processes by acting as a cellular receptor of M. genitalium. CypA also plays a critical role in infection or the life cycle of certain parasites or host immune regulation. Moreover, we summarized the current understanding of CypA inhibitors acting as host-targeting antiviral agents, thus opening an avenue for the treatment of multiple viral infections due to their broad antiviral effects and ability to effectively prevent drug resistance. Therefore, the antiviral effect of CypA has the potential to promote CypA inhibitors as host-targeting drugs to CypA-involved etiological agent infections and human diseases. Key points • CypA is involved in the replication and infection of several viruses, pathogenic bacteria, mycoplasma, and parasites. • CypA inhibitors are in a strong position to inhibit the infection of viruses, bacterial, and mycoplasma.
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Affiliation(s)
- Yating Liao
- Institute of Pathogenic Biology, Hengyang Medical College, University of South China, Hunan Provincial Key Laboratory for Special Pathogens Prevention and Control, No. 28, West Changsheng Road, Hengyang City, 421001 Hunan Province People’s Republic of China
| | - Dan Luo
- Institute of Pathogenic Biology, Hengyang Medical College, University of South China, Hunan Provincial Key Laboratory for Special Pathogens Prevention and Control, No. 28, West Changsheng Road, Hengyang City, 421001 Hunan Province People’s Republic of China
| | - Kailan Peng
- Institute of Pathogenic Biology, Hengyang Medical College, University of South China, Hunan Provincial Key Laboratory for Special Pathogens Prevention and Control, No. 28, West Changsheng Road, Hengyang City, 421001 Hunan Province People’s Republic of China
| | - Yanhua Zeng
- Institute of Pathogenic Biology, Hengyang Medical College, University of South China, Hunan Provincial Key Laboratory for Special Pathogens Prevention and Control, No. 28, West Changsheng Road, Hengyang City, 421001 Hunan Province People’s Republic of China
- Department of Dermatology and Venereology, The First Affiliated Hospital, University of South China, Hengyang City, 421001 Hunan Province People’s Republic of China
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8
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Kim GW, Imam H, Khan M, Siddiqui A. N6-Methyladenosine modification of hepatitis B and C viral RNAs attenuates host innate immunity via RIG-I signaling. J Biol Chem 2020; 295:13123-13133. [PMID: 32719095 PMCID: PMC7489896 DOI: 10.1074/jbc.ra120.014260] [Citation(s) in RCA: 85] [Impact Index Per Article: 21.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2020] [Revised: 07/20/2020] [Indexed: 12/25/2022] Open
Abstract
N6-Methyladenosine (m6A), the methylation of the adenosine base at the nitrogen 6 position, is the most common epitranscriptomic modification of mRNA that affects a wide variety of biological functions. We have previously reported that hepatitis B viral RNAs are m6A-modified, displaying a dual functional role in the viral life cycle. Here, we show that cellular m6A machinery regulates host innate immunity against hepatitis B and C viral infections by inducing m6A modification of viral transcripts. The depletion of the m6A writer enzymes (METTL3 and METTL14) leads to an increase in viral RNA recognition by retinoic acid-inducible gene I (RIG-I), thereby stimulating type I interferon production. This is reversed in cells in which m6A METTL3 and METTL14 are overexpressed. The m6A modification of viral RNAs renders RIG-I signaling less effective, whereas single nucleotide mutation of m6A consensus motif of viral RNAs enhances RIG-I sensing activity. Importantly, m6A reader proteins (YTHDF2 and YTHDF3) inhibit RIG-I-transduced signaling activated by viral RNAs by occupying m6A-modified RNAs and inhibiting RIG-I recognition. Collectively, our results provide new insights into the mechanism of immune evasion via m6A modification of viral RNAs.
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Affiliation(s)
- Geon-Woo Kim
- Division of Infectious Diseases, Department of Medicine, University of California, San Diego, La Jolla, California, USA
| | - Hasan Imam
- Division of Infectious Diseases, Department of Medicine, University of California, San Diego, La Jolla, California, USA
| | - Mohsin Khan
- Division of Infectious Diseases, Department of Medicine, University of California, San Diego, La Jolla, California, USA
| | - Aleem Siddiqui
- Division of Infectious Diseases, Department of Medicine, University of California, San Diego, La Jolla, California, USA.
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Mundim AEDFM, de Castro FDOFD, Albuquerque MBB, Vilanova-Costa CAST, Pfrimer IAH, Silva AMTC. Major mutations in the NS3 gene region of hepatitis C virus related to the resistance to direct acting antiviral drugs: a systematic review. Virusdisease 2020; 31:220-228. [PMID: 32904849 DOI: 10.1007/s13337-020-00616-9] [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: 02/10/2020] [Accepted: 07/20/2020] [Indexed: 10/23/2022] Open
Abstract
Hepatitis C virus (HCV) remains a global public health problem with high prevalence rates and chronicity of infection. Present work aimed to describe the main mutations in the NS3 region of the HCV genome related to the resistance of patients to the currently available direct-acting antivirals (DAAs). To guide the study description, the preferred items in the PRISMA protocol for systematic review were used. The data collected were HCV genotypes and subtypes and mutations in HCV NS3, general and stratified by continent. The 10 papers selected for this systematic review reported studies in seven countries, on three continents, and generated data of 2937 patients. The most frequent HCV subtype was 1a. Prevalence of genotypes suggested that there were few demographic regions reached by the studies, since there were regional variations in the type of genotypes reported in the available bibliographies. Of the total study population, 35.3% (n = 1037) had mutations in the NS3 gene region of HCV, suggesting a high rate of resistance to DAAs and a low sustained virologic response among those who used some therapeutic option. Ten major mutations were identified: Q80K, V170I, S122G, V36L, T54S, D168Q, A156S, Q80G, S122R, and V55A. The Q80K mutation was the highlight of the study, appearing not only with greater representativity (61.6%) but also as the only one described in the three continents analyzed. This systematic review reinforces the need to carry out more studies of detection of these mutations to fill in all information gaps that might help in optimization of treatment.
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Affiliation(s)
- Ana Elisa de Figueiredo Miranda Mundim
- Programa de Pós-Graduação em Ciências Ambientais e Saúde, Pontifícia Universidade Católica de Goiás, Avenida Universitária 1.440, Setor Universitário, Campus 1, Área 4, Goiânia, GO CEP: 74605-010 Brazil
| | - Fernanda de Oliveira Feitosa de de Castro
- Programa de Pós-Graduação em Ciências Ambientais e Saúde, Pontifícia Universidade Católica de Goiás, Avenida Universitária 1.440, Setor Universitário, Campus 1, Área 4, Goiânia, GO CEP: 74605-010 Brazil
| | - Marina Brandão Braz Albuquerque
- Programa de Pós-Graduação em Ciências Ambientais e Saúde, Pontifícia Universidade Católica de Goiás, Avenida Universitária 1.440, Setor Universitário, Campus 1, Área 4, Goiânia, GO CEP: 74605-010 Brazil
| | | | - Irmtraut Araci Hoffmann Pfrimer
- Programa de Pós-Graduação em Ciências Ambientais e Saúde, Pontifícia Universidade Católica de Goiás, Avenida Universitária 1.440, Setor Universitário, Campus 1, Área 4, Goiânia, GO CEP: 74605-010 Brazil
| | - Antonio Márcio Teodoro Cordeiro Silva
- Programa de Pós-Graduação em Ciências Ambientais e Saúde, Pontifícia Universidade Católica de Goiás, Avenida Universitária 1.440, Setor Universitário, Campus 1, Área 4, Goiânia, GO CEP: 74605-010 Brazil
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Schmit D, Milewicz U, Boerneke MA, Burley S, Walsworth K, Um J, Hecht D, Hermann T, Bergdahl BM. Syntheses and Binding Testing of N1-Alkylamino-Substituted 2-Aminobenzimidazole Analogues Targeting the Hepatitis C Virus Internal Ribosome Entry Site. Aust J Chem 2020. [DOI: 10.1071/ch19526] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
A series of 2-aminobenzimidazole analogues have been synthesised and tested for binding to a previously established RNA target for viral translation inhibitors in the internal ribosome entry site (IRES) of the hepatitis C virus (HCV). Synthesis of new inhibitor compounds followed a highly convergent strategy which allowed for incorporation of diverse tertiary amino substituents in high overall yields (eight-steps, 4–22%). Structure–activity relationship (SAR) studies focussed on the tertiary amine substituent involved in hydrogen bonding with the RNA backbone at the inhibitor binding site. The SAR study was further correlated with in silico docking experiments. Analogous compounds showed promising activities (half maximal effective concentration, EC50: 21–89µM). Structures of the synthesised analogues and a correlation to their mode of binding, provided the opportunity to explore parameters required for selective targeting of the HCV IRES at the subdomain IIa which acts as an RNA conformational switch in HCV translation.
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Peres-da-Silva A, Antunes D, Quintanilha Torres AL, Caffarena ER, Lampe E. Effects of the Q80K Polymorphism on the Physicochemical Properties of Hepatitis C Virus Subtype 1a NS3 Protease. Viruses 2019; 11:E691. [PMID: 31366046 PMCID: PMC6723822 DOI: 10.3390/v11080691] [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: 03/29/2019] [Revised: 06/04/2019] [Accepted: 06/13/2019] [Indexed: 02/07/2023] Open
Abstract
Hepatitis C virus genotype 1a (HCV-1a) comprises clades I and II. The Q80K polymorphism is found predominantly in clade I but rarely in clade II. Here, we investigated whether natural polymorphisms in HCV-1a clade II entailed structural protein changes when occurrence of the Q80K variant was simulated. Based on HCV-1a clade I and II protein sequences, the structure of the HCV-1a Q80K mutant NS3-4A was obtained by comparative modeling. Its physicochemical properties were studied by molecular dynamics simulations and network analysis. Results demonstrate that, in the presence of the K80 variant, clade II protease polymorphisms A91 and S/G174 led to variations in hydrogen bond occupancies. Structural analyses revealed differences in (i) flexibility of the H57 catalytic residue on the NS3 protease and (ii) correlations between amino acids on the NS3 protease and the NS4A cofactor. The latter indicated possible destabilization of interactions, resulting in increased separation of these proteins. The present findings describe how the relationships between different HCV-1a NS3 protease amino acid residues could affect the appearance of viral variants and the existence of distinct genetic barriers to HCV-1a isolates.
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Affiliation(s)
- Allan Peres-da-Silva
- Laboratório de Hepatites Virais, Instituto Oswaldo Cruz/FIOCRUZ, Rio de Janeiro, RJ 21040-900, Brazil.
| | - Deborah Antunes
- Programa de Computação Científica, Instituto Oswaldo Cruz/FIOCRUZ, Rio de Janeiro, RJ 21040-900, Brazil
| | - André Luiz Quintanilha Torres
- Laboratório de Biologia Computacional e Sistemas, Instituto Oswaldo Cruz/FIOCRUZ, Rio de Janeiro, RJ 21040-900, Brazil
- Laboratório de Bioinformática, Departamento de Bioquímica, Instituto de Química, Universidade Federal do Rio de Janeiro/UFRJ, Rio de Janeiro, RJ 21941-909, Brazil
| | - Ernesto Raul Caffarena
- Programa de Computação Científica, Instituto Oswaldo Cruz/FIOCRUZ, Rio de Janeiro, RJ 21040-900, Brazil
| | - Elisabeth Lampe
- Laboratório de Hepatites Virais, Instituto Oswaldo Cruz/FIOCRUZ, Rio de Janeiro, RJ 21040-900, Brazil
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Li Z, Liu Q. Proprotein convertase subtilisin/kexin type 9 inhibits hepatitis C virus replication through interacting with NS5A. J Gen Virol 2017; 99:44-61. [PMID: 29235977 DOI: 10.1099/jgv.0.000987] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Proprotein convertase subtilisin/kexin type 9 (PCSK9) is a serine protease actively involved in regulating lipid homeostasis. Although PCSK9 has been shown to inhibit hepatitis C virus (HCV) entry and replication, the underlying mechanisms have not been thoroughly characterized. Moreover, whether PCSK9 regulates HCV translation and assembly/secretion has not been determined. We therefore further studied the effects of PCSK9 on the HCV life cycle. We showed that PCSK9 did not affect HCV translation or assembly/secretion. Overexpression of PCSK9 inhibited HCV replication in HCV genomic replicon cells in a dose-dependent manner and after cell culture-derived HCV (HCVcc) infection. Knocking down PCSK9 increased HCV replication. The gain-of-function (D374Y) or loss-of-function (Δaa. 31-52) PCSK9 mutants for low-density lipoprotein receptor (LDLR) degradation had no effect on HCV replication, suggesting that HCV replication inhibition by PCSK9 was not due to LDLR degradation. The uncleaved ProPCSK9, but not cleaved PCSK9, down-regulated HCV replication, suggesting that the auto-cleavage of PCSK9 affected HCV replication. We also found that PCSK9 interacted with NS5A through NS5A aa. 95-215, and this region played an important role in NS5A dimerization, NS5A-RNA binding and was essential for HCV replication. More importantly, NS5A dimerization and NS5A-RNA binding were suppressed by PCSK9 upon interaction. These results suggested that PCSK9 inhibited HCV replication through interaction with NS5A. Our study should help optimize anti-HCV treatment regimen in patients with abnormal lipid profiles.
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Affiliation(s)
- Zhubing Li
- VIDO-InterVac, School of Public Health Vaccinology and Immunotherapeutics, University of Saskatchewan, Saskatoon, Saskatchewan, Canada
| | - Qiang Liu
- Department of Veterinary Microbiology, University of Saskatchewan, Saskatoon, Saskatchewan, Canada.,VIDO-InterVac, School of Public Health Vaccinology and Immunotherapeutics, University of Saskatchewan, Saskatoon, Saskatchewan, Canada
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13
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Wang S, Chen Y, Xu X, Hu W, Shen H, Chen J. Prevalence of hepatitis B virus and hepatitis C virus infection in patients with systemic lupus erythematosus: a systematic review and meta-analysis. Oncotarget 2017; 8:102437-102445. [PMID: 29254259 PMCID: PMC5731969 DOI: 10.18632/oncotarget.22261] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2017] [Accepted: 09/22/2017] [Indexed: 02/06/2023] Open
Abstract
We attempted to explore the prevalence of HBV and HCV infections in patients with systemic lupus erythematous (SLE) via a systematic review. Articles published before June 2017 and, related to prevalence rates for HBV and HCV infection in SLE patient were identified in PubMed, Embase, CNKI, and Wanfang databases. Based on these searches 22 studies were selected for further analysis. The OR of HBsAg positive rate in SLE patients compared with control population was 0.28, with significant heterogeneity identified among the studies (I2 = 92%, P < 0.00001). Following exclusion of one study, the adjusted OR of HBsAg in patients with SLE was 0.24, and no significant heterogeneity was observed (I2 = 32%, P = 0.15). The adjusted OR of HBcAb positive rate in SLE patients compared with control population was 0.40, with no significant heterogeneity between studies (I2 = 0%, P = 0.56). The risk of having HCV infection by SLE patients was higher compared with the control subjects (OR = 2.91). In conclusion, this meta-analysis suggested that SLE might exert a role of protection against HBV but not for HCV infection. Further epidemiological and experimental studies are necessary to explore the role and mechanisms by which SLE affects HBV/HCV infections.
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Affiliation(s)
- Sen Wang
- Department of Laboratory Medicine, Nanjing Drum Tower Hospital, Nanjing University Medical School, Nanjing 210008, Jiangsu Province, China
| | - Yuxin Chen
- Department of Laboratory Medicine, Nanjing Drum Tower Hospital, Nanjing University Medical School, Nanjing 210008, Jiangsu Province, China
| | - Xuejing Xu
- Department of Laboratory Medicine, Nanjing Drum Tower Hospital, Nanjing University Medical School, Nanjing 210008, Jiangsu Province, China
| | - Wei Hu
- Department of Laboratory Medicine, Nanjing Drum Tower Hospital, Nanjing University Medical School, Nanjing 210008, Jiangsu Province, China
| | - Han Shen
- Department of Laboratory Medicine, Nanjing Drum Tower Hospital, Nanjing University Medical School, Nanjing 210008, Jiangsu Province, China
| | - Junhao Chen
- Department of Laboratory Medicine, Nanjing Drum Tower Hospital, Nanjing University Medical School, Nanjing 210008, Jiangsu Province, China
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14
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Yang N, Sun C, Zhang L, Liu J, Song F. Identification and Analysis of Novel Inhibitors against NS3 Helicase and NS5B RNA-Dependent RNA Polymerase from Hepatitis C Virus 1b (Con1). Front Microbiol 2017; 8:2153. [PMID: 29209282 PMCID: PMC5701637 DOI: 10.3389/fmicb.2017.02153] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2017] [Accepted: 10/20/2017] [Indexed: 01/22/2023] Open
Abstract
Hepatitis C virus (HCV) leads to severe liver diseases, including liver fibrosis, cirrhosis and hepatocellular carcinoma. Non-structural protein 3 helicase (NS3h) and non-structural protein 5B RNA-dependent RNA polymerase (NS5B) are involved in the replication of HCV RNA genome, and have been proved to be excellent targets for discovery of direct-acting antivirals. In this study, two high-throughput screening systems, fluorescence polarization (FP)-based ssDNA binding assay and fluorescence intensity (FI)-based dsRNA formation assay, were constructed to identify candidate NS3h and NS5B inhibitors, respectively. A library of approximately 800 small molecules and crude extracts, derived from marine microorganisms or purchased from the National Compound Resource Center, China, were screened, with three hits selected for further study. Natural compound No.3A5, isolated from marine fungi, inhibited NS3h activity with an IC50 value of 2.8 μM. We further demonstrated that compound No.3A5 inhibited the abilities of NS3h to bind ssDNA in electrophoretic mobility shift assay and to hydrolyze ATP. The NS3h-inhibitory activity of compound No.3A5 was reversible in our dilution assay, which indicated there was no stable NS3h-No.3A5 complex formed. Additionally, compound No.3A5 exhibited no binding selectivity on NS3h or single strand binding protein of Escherichia coli. In NS5B assays, commercial compounds No.39 and No.94 previously reported as kinase inhibitors were found to disrupt dsRNA formation, and their IC50 values were 62.9 and 18.8 μM, respectively. These results highlight how identifying new uses for existing drugs is an effective method for discovering novel HCV inhibitors. To our knowledge, all inhibitors reported in this study were originally discovered with HCV anti-non-structural protein activities in vitro.
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Affiliation(s)
- Na Yang
- Key Laboratory of Experimental Marine Biology, Institute of Oceanology, Chinese Academy of Sciences, Qingdao, China.,Laboratory for Marine Biology and Biotechnology, Qingdao National Laboratory for Marine Science and Technology, Qingdao, China
| | - Chaomin Sun
- Key Laboratory of Experimental Marine Biology, Institute of Oceanology, Chinese Academy of Sciences, Qingdao, China.,Laboratory for Marine Biology and Biotechnology, Qingdao National Laboratory for Marine Science and Technology, Qingdao, China
| | - Lixin Zhang
- Laboratory for Marine Biology and Biotechnology, Qingdao National Laboratory for Marine Science and Technology, Qingdao, China.,State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai, China
| | - Jianguo Liu
- Key Laboratory of Experimental Marine Biology, Institute of Oceanology, Chinese Academy of Sciences, Qingdao, China.,Laboratory for Marine Biology and Biotechnology, Qingdao National Laboratory for Marine Science and Technology, Qingdao, China
| | - Fuhang Song
- Key Laboratory of Pathogenic Microbiology and Immunology, Institute of Microbiology, Chinese Academy of Sciences, Beijing, China
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15
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Kwak J, Choi JH, Jang KL. Hepatitis C virus Core overcomes all- trans retinoic acid-induced apoptosis in human hepatoma cells by inhibiting p14 expression via DNA methylation. Oncotarget 2017; 8:85584-85598. [PMID: 29156743 PMCID: PMC5689633 DOI: 10.18632/oncotarget.20337] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2016] [Accepted: 07/25/2017] [Indexed: 01/15/2023] Open
Abstract
All-trans retinoic acid (ATRA), the most biologically active metabolite of vitamin A, is known to induce p14 expression via promoter hypomethylation to activate the p14-MDM2-p53 pathway, which leads to activation of the p53-dependent apoptotic pathway and subsequent induction of apoptosis in human hepatoma cells. In the present study, we found that hepatitis C virus (HCV) Core derived from ectopic expression or HCV infection overcomes ATRA-induced apoptosis in p53-positive hepatoma cells. For this effect, HCV Core upregulated both protein levels and enzyme activities of DNA methyltransferase 1 (DNMT1), DNMT3a, and DNMT3b and thereby repressed p14 expression via promoter hypermethylation, resulting in inactivation of the pathway leading to p53 accumulation in the presence of ATRA. As a result, HCV Core prevented ATRA from activating several apoptosis-related molecules, including Bax, p53 upregulated modulator of apoptosis, caspase-9, caspase-3, and poly (ADP-ribose) polymerase. In addition, complementation of p14 in the Core-expressing cells by either ectopic expression or treatment with 5-Aza-2′dC almost completely abolished the potential of HCV Core to suppress ATRA-induced apoptosis. Based on these observations, we conclude that HCV Core executes its oncogenic potential by suppressing the p53-dependent apoptosis induced by ATRA in human hepatoma cells.
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Affiliation(s)
- Juri Kwak
- Department of Microbiology, College of Natural Sciences, Pusan National University, Busan 609-735, Republic of Korea
| | - Jung-Hye Choi
- Department of Microbiology, College of Natural Sciences, Pusan National University, Busan 609-735, Republic of Korea
| | - Kyung Lib Jang
- Department of Microbiology, College of Natural Sciences, Pusan National University, Busan 609-735, Republic of Korea
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16
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The p7 viroporin of the hepatitis C virus contributes to liver inflammation by stimulating production of Interleukin-1β. Biochim Biophys Acta Mol Basis Dis 2017; 1863:712-720. [DOI: 10.1016/j.bbadis.2016.12.006] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2016] [Revised: 12/08/2016] [Accepted: 12/12/2016] [Indexed: 12/12/2022]
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17
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Repression of the Internal Ribosome Entry Site-dependent Translation of Hepatitis C Virus by an Engineered PUF Protein. HEPATITIS MONTHLY 2017. [DOI: 10.5812/hepatmon.45022] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/13/2023]
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18
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Kwak J, Tiwari I, Jang KL. Hepatitis C virus core activates proteasomal activator 28γ expression via upregulation of p53 levels to control virus propagation. J Gen Virol 2017; 98:56-67. [DOI: 10.1099/jgv.0.000655] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Affiliation(s)
- Juri Kwak
- Department of Microbiology, College of Natural Science, Pusan National University, Busan 46241, Republic of Korea
| | - Indira Tiwari
- 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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19
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Tao W, Gan T, Lu J, Zhong J. A profiling study of a newly developed HCVcc strain PR63cc's sensitivity to direct-acting antivirals. Antiviral Res 2016; 139:18-24. [PMID: 28025084 DOI: 10.1016/j.antiviral.2016.12.009] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2016] [Accepted: 12/15/2016] [Indexed: 02/08/2023]
Abstract
The development of direct-acting antivirals (DAAs) has significantly improved hepatitis C virus (HCV) treatment. However, drug resistance remains a potential concern in the real-world DAA-based therapies. We previously developed a novel full-length genotype 2a HCVcc clone PR63cc directly from clinical isolates. Here in this study, we compared the sensitivity of PR63cc and JFH1 to 12 different DAAs most of which are either already in clinical use or in the late clinical development phase. For NS5B inhibitors, PR63cc and JFH1 displayed comparable sensitivity to nucleoside/nucleotide analogues sofosbuvir and 2'-C-methyladenosine, while PR63cc was 4-fold more sensitive than JFH1 to nesbuvir, a non-nucleoside inhibitor. Interestingly, PR63cc and JFH1 were both completely resistant to dasabuvir which efficiently inhibited the replication of genotype 1b HCV replicon. For NS5A inhibitors, while PR63cc was as sensitive as JFH1 to ombitasvir and velpatasvir, it was much more resistant than JFH1 to daclatasvir and ledipasvir, which was mainly due to methionine at amino acid residue 31 of NS5A. For NS3 inhibitors, PR63cc was generally less sensitive than JFH1 to simeprevir, grazoprevir, asunaprevir and paritaprevir. Serine at residue 67 of NS3 was identified to be a resistance-associated variant (RAV) for asunaprevir. Finally, we showed that PR63cc was more resistant than JFH1 to the asunaprevir/daclatasvir combination treatment. In summary, our study systemically analyzed the DAA sensitivity of a new HCVcc strain and identified critical RAVs. These results are not only important for monitoring the emergence of drug-resistant mutations of current DAA therapies, but also valuable for developing next-generation DAAs.
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Affiliation(s)
- Wanyin Tao
- Unit of Viral Hepatitis, CAS Key Laboratory of Molecular Virology & Immunology, Institut Pasteur of Shanghai, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai, 200031, PR China
| | - Tianyu Gan
- Unit of Viral Hepatitis, CAS Key Laboratory of Molecular Virology & Immunology, Institut Pasteur of Shanghai, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai, 200031, PR China; University of Chinese Academy of Sciences, Beijing, 100049, PR China
| | - Jie Lu
- Unit of Viral Hepatitis, CAS Key Laboratory of Molecular Virology & Immunology, Institut Pasteur of Shanghai, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai, 200031, PR China
| | - Jin Zhong
- Unit of Viral Hepatitis, CAS Key Laboratory of Molecular Virology & Immunology, Institut Pasteur of Shanghai, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai, 200031, PR China.
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20
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Hepatitis C virus core protein inhibits E6AP expression via DNA methylation to escape from ubiquitin-dependent proteasomal degradation. Cancer Lett 2016; 380:59-68. [DOI: 10.1016/j.canlet.2016.06.008] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2016] [Revised: 06/03/2016] [Accepted: 06/13/2016] [Indexed: 01/16/2023]
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21
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Chadha S, Sharma U, Chaudhary A, Prakash C, Gupta S, Venkatesh S. Molecular epidemiological analysis of three hepatitis C virus outbreaks in Jammu and Kashmir State, India. J Med Microbiol 2016; 65:804-813. [PMID: 27357565 DOI: 10.1099/jmm.0.000284] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
Outbreaks of hepatitis C virus (HCV) infection are associated with unsafe injection practices, intravenous drug abuse and other exposure to blood and body fluids. We report here three outbreaks of HCV infection from Jammu and Kashmir (J&K) State, India, which occurred over a period of 3 years and in which molecular epidemiological investigations identified a presumptive common source of infection, most likely a single healthcare venue. Representative blood samples collected from cases of hepatitis C were sent to the National Centre for Disease Control (NCDC) for molecular characterization. These samples were positive by HCV ELISA. Subsequently, specimens were also tested for the presence of HCV RNA by RT-PCR. Sequencing was carried out for all positive samples. A total of 812 cases were laboratory confirmed by HCV ELISA; a total of 115 samples were sent to the NCDC for RT-PCR, and 77 were positive. Subtype 3a of HCV was found in all samples from Anantnag (February 2013); and for subtype 3b, in all samples from Srinagar (May 2015). Subtypes 3a and 3g were identified from two samples from the Kulgam outbreak (July 2014). A detailed epidemiological investigation should be conducted whenever a cluster of HCV cases is revealed, as this potentially allows for the identification of larger outbreaks. Epidemiological investigations of outbreaks should be further supported by inclusion of molecular tests. Efforts to limit therapeutic injections to only those cases having strong medical/surgical indications and to restrict the use of non-sterile needles are essential to prevent transmission of HCV.
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Affiliation(s)
- Sanjim Chadha
- Division of Biotechnology and Molecular Diagnostics, National Centre for Disease Control, Directorate General of Health Services, Ministry of Health & Family Welfare, Government of India, 22-Sham Nath Marg, Delhi 110054, India
| | - Uma Sharma
- Division of Biotechnology and Molecular Diagnostics, National Centre for Disease Control, Directorate General of Health Services, Ministry of Health & Family Welfare, Government of India, 22-Sham Nath Marg, Delhi 110054, India
| | - Artee Chaudhary
- Division of Biotechnology and Molecular Diagnostics, National Centre for Disease Control, Directorate General of Health Services, Ministry of Health & Family Welfare, Government of India, 22-Sham Nath Marg, Delhi 110054, India
| | - Charu Prakash
- Division of Biotechnology and Molecular Diagnostics, National Centre for Disease Control, Directorate General of Health Services, Ministry of Health & Family Welfare, Government of India, 22-Sham Nath Marg, Delhi 110054, India
| | - Sunil Gupta
- Division of Biotechnology and Molecular Diagnostics, National Centre for Disease Control, Directorate General of Health Services, Ministry of Health & Family Welfare, Government of India, 22-Sham Nath Marg, Delhi 110054, India
| | - S Venkatesh
- Division of Biotechnology and Molecular Diagnostics, National Centre for Disease Control, Directorate General of Health Services, Ministry of Health & Family Welfare, Government of India, 22-Sham Nath Marg, Delhi 110054, India
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22
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Broering R, Trippler M, Werner M, Real CI, Megger DA, Bracht T, Schweinsberg V, Sitek B, Eisenacher M, Meyer HE, Baba HA, Weber F, Hoffmann AC, Gerken G, Schlaak JF. Hepatic expression of proteasome subunit alpha type-6 is upregulated during viral hepatitis and putatively regulates the expression of ISG15 ubiquitin-like modifier, a proviral host gene in hepatitis C virus infection. J Viral Hepat 2016; 23:375-86. [PMID: 26833585 DOI: 10.1111/jvh.12508] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/09/2015] [Accepted: 12/19/2015] [Indexed: 12/12/2022]
Abstract
The interferon-stimulated gene 15 (ISG15) plays an important role in the pathogenesis of hepatitis C virus (HCV) infection. ISG15-regulated proteins have previously been identified that putatively affect this proviral interaction. The present observational study aimed to elucidate the relation between ISG15 and these host factors during HCV infection. Transcriptomic and proteomic analyses were performed using liver samples of HCV-infected (n = 54) and uninfected (n = 10) or HBV-infected controls (n = 23). Primary human hepatocytes (PHH) were treated with Toll-like receptor ligands, interferons and kinase inhibitors. Expression of ISG15 and proteasome subunit alpha type-6 (PSMA6) was suppressed in subgenomic HCV replicon cell lines using specific siRNAs. Comparison of hepatic expression patterns revealed significantly increased signals for ISG15, IFIT1, HNRNPK and PSMA6 on the protein level as well as ISG15, IFIT1 and PSMA6 on the mRNA level in HCV-infected patients. In contrast to interferon-stimulated genes, PSMA6 expression occurred independent of HCV load and genotype. In PHH, the expression of ISG15 and PSMA6 was distinctly induced by poly(I:C), depending on IRF3 activation or PI3K/AKT signalling, respectively. Suppression of PSMA6 in HCV replicon cells led to significant induction of ISG15 expression, thus combined knock-down of both genes abrogated the antiviral effect induced by the separate suppression of ISG15. These data indicate that hepatic expression of PSMA6, which is upregulated during viral hepatitis, likely depends on TLR3 activation. PSMA6 affects the expression of immunoregulatory ISG15, a proviral factor in the pathogenesis of HCV infection. Therefore, the proteasome might be involved in the enigmatic interaction between ISG15 and HCV.
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Affiliation(s)
- R Broering
- Department of Gastroenterology and Hepatology, University Hospital, University of Duisburg-Essen, Essen, Germany
| | - M Trippler
- Department of Gastroenterology and Hepatology, University Hospital, University of Duisburg-Essen, Essen, Germany
| | - M Werner
- Department of Gastroenterology and Hepatology, University Hospital, University of Duisburg-Essen, Essen, Germany
| | - C I Real
- Department of Gastroenterology and Hepatology, University Hospital, University of Duisburg-Essen, Essen, Germany
| | - D A Megger
- Medizinisches Proteom-Center, Ruhr-Universität Bochum, Bochum, Germany
| | - T Bracht
- Medizinisches Proteom-Center, Ruhr-Universität Bochum, Bochum, Germany
| | - V Schweinsberg
- Medizinisches Proteom-Center, Ruhr-Universität Bochum, Bochum, Germany
| | - B Sitek
- Medizinisches Proteom-Center, Ruhr-Universität Bochum, Bochum, Germany
| | - M Eisenacher
- Medizinisches Proteom-Center, Ruhr-Universität Bochum, Bochum, Germany
| | - H E Meyer
- Medizinisches Proteom-Center, Ruhr-Universität Bochum, Bochum, Germany.,Leibniz Institute for Analytical Sciences - ISAS, Dortmund, Germany
| | - H A Baba
- Department of Pathology and Neuropathology, University Hospital of Essen, Essen, Germany
| | - F Weber
- Department of General, Visceral and Transplantation Surgery, University Hospital of Essen, Essen, Germany
| | - A-C Hoffmann
- Department of Medicine (Cancer Research), Molecular Oncology Risk-Profile Evaluation, University Hospital of Essen, Essen, Germany
| | - G Gerken
- Department of Gastroenterology and Hepatology, University Hospital, University of Duisburg-Essen, Essen, Germany
| | - J F Schlaak
- Department of Gastroenterology and Hepatology, University Hospital, University of Duisburg-Essen, Essen, Germany
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23
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Li X, Niu Y, Cheng M, Chi X, Liu X, Yang W. AP1S3 is required for hepatitis C virus infection by stabilizing E2 protein. Antiviral Res 2016; 131:26-34. [PMID: 27079945 DOI: 10.1016/j.antiviral.2016.04.006] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2015] [Revised: 04/05/2016] [Accepted: 04/08/2016] [Indexed: 10/22/2022]
Abstract
Hepatitis C virus (HCV) infects 130 million people worldwide and is a leading cause of liver cirrhosis, end-stage liver disease and hepatocellular carcinoma. The interactions between viral elements and host factors play critical role on HCV invade, replication and release. Here, we identified adaptor protein complex 1 sigma 3 subunit (AP1S3) as a dependency factor for the efficient HCV infection in hepatoma cells. AP1S3 silencing in cultivated Huh7.5.1 cells significantly reduced the production of HCV progeny particles. Immunoprecipitation analysis revealed that AP1S3 interacted with the HCV E2 protein. With this interaction, AP1S3 could protect HCV E2 from ubiquitin-mediated proteasomal degradation. Using in vivo ubiquitylation assay, we identified that E6-Associated Protein (E6AP) was associated with HCV E2. In addition, treatment with synthetic peptide that contains the AP1S3-recognized motif inhibited HCV infection in Huh7.5.1 cells. Our data reveal AP1 as a novel host network that is required by viruses during infection and provides a potential target for developing broad-spectrum anti-virus strategies.
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Affiliation(s)
- Xiang Li
- MOH Key Laboratory of Systems Biology of Pathogens, Institute of Pathogen Biology, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, 100176, China
| | - Yuqiang Niu
- MOH Key Laboratory of Systems Biology of Pathogens, Institute of Pathogen Biology, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, 100176, China
| | - Min Cheng
- MOH Key Laboratory of Systems Biology of Pathogens, Institute of Pathogen Biology, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, 100176, China
| | - Xiaojing Chi
- MOH Key Laboratory of Systems Biology of Pathogens, Institute of Pathogen Biology, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, 100176, China
| | - Xiuying Liu
- MOH Key Laboratory of Systems Biology of Pathogens, Institute of Pathogen Biology, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, 100176, China
| | - Wei Yang
- MOH Key Laboratory of Systems Biology of Pathogens, Institute of Pathogen Biology, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, 100176, China.
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24
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Kumar A, Das S, Mullick R, Lahiri P, Tatineni R, Goswami D, Bhat P, Torresi J, Gowans EJ, Karande AA, Das S. Immune responses against hepatitis C virus genotype 3a virus-like particles in mice: A novel VLP prime-adenovirus boost strategy. Vaccine 2015; 34:1115-25. [PMID: 26700891 DOI: 10.1016/j.vaccine.2015.11.061] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2015] [Revised: 10/15/2015] [Accepted: 11/19/2015] [Indexed: 12/17/2022]
Abstract
Chronic hepatitis C virus (HCV) infection represents a major health threat to global population. In India, approximately 15-20% of cases of chronic liver diseases are caused by HCV infection. Although, new drug treatments hold great promise for HCV eradication in infected individuals, the treatments are highly expensive. A vaccine for preventing or treating HCV infection would be of great value, particularly in developing countries. Several preclinical trials of virus-like particle (VLP) based vaccine strategies are in progress throughout the world. Previously, using baculovirus based system, we have reported the production of hepatitis C virus-like particles (HCV-LPs) encoding structural proteins for genotype 3a, which is prevalent in India. In the present study, we have generated HCV-LPs using adenovirus based system and tried different immunization strategies by using combinations of both kinds of HCV-LPs with other genotype 3a-based immunogens. HCV-LPs and peptides based ELISAs were used to evaluate antibody responses generated by these combinations. Cell-mediated immune responses were measured by using T-cell proliferation assay and intracellular cytokine staining. We observed that administration of recombinant adenoviruses expressing HCV structural proteins as final booster enhances both antibody as well as T-cell responses. Additionally, reduction of binding of VLP and JFH1 virus to human hepatocellular carcinoma cells demonstrated the presence of neutralizing antibodies in immunized sera. Taken together, our results suggest that the combined regimen of VLP followed by recombinant adenovirus could more effectively inhibit HCV infection, endorsing the novel vaccine strategy.
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Affiliation(s)
- Anuj Kumar
- Department of Microbiology and Cell Biology, Indian Institute of Science, Bangalore 560012, India
| | - Soma Das
- Department of Biochemistry, Indian Institute of Science, Bangalore 560012, India
| | - Ranajoy Mullick
- Department of Microbiology and Cell Biology, Indian Institute of Science, Bangalore 560012, India
| | - Priyanka Lahiri
- Department of Microbiology and Cell Biology, Indian Institute of Science, Bangalore 560012, India
| | - Ranjitha Tatineni
- Department of Microbiology and Cell Biology, Indian Institute of Science, Bangalore 560012, India
| | - Debashree Goswami
- Department of Microbiology and Cell Biology, Indian Institute of Science, Bangalore 560012, India
| | - Prasanna Bhat
- Department of Microbiology and Cell Biology, Indian Institute of Science, Bangalore 560012, India
| | - Joseph Torresi
- Department of Microbiology and Immunology, The Peter Doherty Institute for Infection and Immunity, University of Melbourne, Parkville, Victoria 3000, Australia
| | - Eric James Gowans
- Virology Laboratory, Discipline of Surgery, University of Adelaide, Basil Hetzel Institute for Translational Medicine, Adelaide, SA 5011, Australia
| | - Anjali Anoop Karande
- Department of Biochemistry, Indian Institute of Science, Bangalore 560012, India
| | - Saumitra Das
- Department of Microbiology and Cell Biology, Indian Institute of Science, Bangalore 560012, India.
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25
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Qi Y, Chen Q, Hao F, Wan Z, Guo H, Lu R, Mao L, Du H, Lu J, Zhang C. Subtype distribution of hepatitis C virus in Jiangsu, China. J Med Virol 2015; 88:498-505. [PMID: 26288243 DOI: 10.1002/jmv.24356] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/13/2015] [Indexed: 12/20/2022]
Abstract
Hepatitis C virus (HCV) genotype distribution varied by regions and transmission modes. In this study, we investigated HCV genotype distribution in five cities of Jiangsu, China, all of which are located in the Yangtze River Delta Region. A total of 363 samples were collected during 2011-2012. C/E2 and NS5B fragments of HCV were amplified using a multiple RT-nested PCR strategy and subjected to sequencing. Phylogenetic analysis was performed for HCV genotyping. Among 106 PCR positive cases, HCV subtypes 1a (0.9%), 1b (61.3%), 2a (15.1%), 3a (4.7%), 3b (9.4%), 6a (6.6%), and 6n (1.9%) were detected. Together with our previous data, we found that HCV subtypes were more among injection drug users (IDUs) (nine) than among general population (GP) (six), and the most common subtype among GP was 1b (73.9%), followed by 2a (14.5%), while the top four common subtypes among IDUs were 3a, 1b, 3b, and 6a, with similar prevalence rates (24.4%, 22.7%, 20.9%, and 17.4%, respectively). There were nine HCV subtypes prevalent among IDUs in Jiangsu, more than those in Xinjiang, Hubei, Yunnan, Guangxi, Guangdong, and Hong Kong. The top four common subtypes among IDUs in Jiangsu covered all the two most common HCV subtypes (except 6n subtype) observed in six targeted provinces/region. These results suggested that Jiangsu may be an important gathering place for various HCV subtypes and the gathering may be involved in the large scale of population migration from other regions of China to Eastern China.
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Affiliation(s)
- Yinle Qi
- Institute of Life Sciences, Jiangsu University, Zhenjiang, Jiangsu, China
| | - Qianqian Chen
- Pathogen Diagnostic Center, Institut Pasteur of Shanghai, Chinese Academy of Sciences, Shanghai, China
| | - Fangyuan Hao
- Institute of Life Sciences, Jiangsu University, Zhenjiang, Jiangsu, China
| | - Zhenzhou Wan
- Medical Laboratory of Taizhou Fourth People's Hospital, Taizhou, Jiangsu, China
| | - Hongxiong Guo
- Jiangsu Center for Disease Control and Prevention, Nanjing, Jiangsu, China
| | - Renfei Lu
- The Third People's Hospital of Nantong, Nantong, Jiangsu, China
| | - Lingxiang Mao
- Zhenjiang Center of Disease Control and Prevention, Zhenjiang, Jiangsu, China
| | - Hong Du
- Clinical Laboratory, The Second Affiliated Hospital of Soochow University, Suzhou, Jiangsu, China
| | - Jian Lu
- Institute of Life Sciences, Jiangsu University, Zhenjiang, Jiangsu, China
| | - Chiyu Zhang
- Institute of Life Sciences, Jiangsu University, Zhenjiang, Jiangsu, China.,Pathogen Diagnostic Center, Institut Pasteur of Shanghai, Chinese Academy of Sciences, Shanghai, China
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TNF-α Induced by Hepatitis C Virus via TLR7 and TLR8 in Hepatocytes Supports Interferon Signaling via an Autocrine Mechanism. PLoS Pathog 2015; 11:e1004937. [PMID: 26023919 PMCID: PMC4449221 DOI: 10.1371/journal.ppat.1004937] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2014] [Accepted: 05/06/2015] [Indexed: 02/07/2023] Open
Abstract
Invasion by infectious pathogens can elicit a range of cytokine responses from host cells. These cytokines provide the initial host defense mechanism. In this report, we demonstrate that TNF-α, a pro-inflammatory cytokine, can be induced by hepatitis C virus (HCV) in its host cells in a biphasic manner. The initial induction of TNF-α by HCV was prompt and could be blocked by the antibody directed against the HCV E2 envelope protein and by chemicals that inhibit endocytosis, indicating the specificity of endocytic uptake of HCV in this induction. Further studies indicated that the induction of TNF-α was dependent on toll-like receptors 7 and 8 (TLR7/8) but not on other intracellular pattern recognition receptors. Consistently, siRNA-mediated gene silencing of the downstream effectors in the TLR7/8 signaling pathway including MyD88, IRAK1, TRAF6, TAK1 and p65 NF-κB suppressed the expression of TNF-α. The role of p65 NF-κB in the induction of TNF-α via transcriptional up-regulation was further confirmed by the chromatin immunoprecipitation assay. TNF-α induced by HCV could activate its own receptor TNFR1 on hepatocytes to suppress HCV replication. This suppressive effect of TNF-α on HCV was due to its role in supporting interferon signaling, as the suppression of its expression led to the loss of IFNAR2 and impaired interferon signaling and the induction of interferon-stimulated genes. In conclusion, our results indicate that hepatocytes can sense HCV infection via TLR7/8 to induce the expression of TNF-α, which inhibits HCV replication via an autocrine mechanism to support interferon signaling. Hepatitis C virus (HCV) patients have increased levels of circulating tumor necrosis factor-α (TNF-α). In this report, we demonstrate that HCV can directly induce the expression of TNF-α in hepatocytes in a biphasic manner via NF-κB. The induction of TNF-α by HCV in the first phase is prompt, requires no HCV gene expression and is dependent on TLR7 and TLR8 and their downstream effectors. TNF-α induced by HCV supports interferon signaling via an autocrine mechanism and suppresses HCV replication, as abolishing the expression of TNF-α or its receptor TNFR1 results in the loss of IFNAR2, a subunit of the type I interferon receptor, and an increase of HCV replication. Our studies thus reveal an interesting interplay between HCV and hepatocytes, with the virus attempting to blunt the IFN response by depleting IFNAR2 and the host cell overcoming this blunting effect of HCV by using TNF-α to restore the expression of IFNAR2.
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Seo YL, Heo S, Jang KL. Hepatitis C virus core protein overcomes H2O2-induced apoptosis by downregulating p14 expression via DNA methylation. J Gen Virol 2015; 96:822-832. [DOI: 10.1099/vir.0.000032] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Affiliation(s)
- Young Lan Seo
- Department of Microbiology, College of Natural Sciences, Pusan National University, Busan, Republic of Korea
| | - Shinhee Heo
- Department of Microbiology, College of Natural Sciences, Pusan National University, Busan, Republic of Korea
| | - Kyung Lib Jang
- Department of Microbiology, College of Natural Sciences, Pusan National University, Busan, Republic of Korea
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Tiwari I, Yoon MH, Park BJ, Jang KL. Hepatitis C virus core protein induces epithelial-mesenchymal transition in human hepatocytes by upregulating E12/E47 levels. Cancer Lett 2015; 362:131-8. [PMID: 25817725 DOI: 10.1016/j.canlet.2015.03.032] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2015] [Revised: 03/21/2015] [Accepted: 03/23/2015] [Indexed: 01/18/2023]
Abstract
Downregulation of E-cadherin is a hallmark of epithelial-mesenchymal transition (EMT), an essential component of cancer progression to more aggressive phenotypes characterized by tumor dedifferentiation, infiltration, and metastasis. However, the underlying mechanism for E-cadherin downregulation in hepatitis C virus (HCV)-associated hepatocellular carcinoma (HCC) is still unclear. In this study, we found that ectopic expression of HCV core protein or infection with HCV in human hepatocytes upregulated the levels of the transcriptional repressors, E12 and E47, resulting in inactivation of the E-cadherin promoter, containing E-box motifs, and subsequent repression of its expression. E12/E47 knock-down almost completely abolished the potential of HCV core protein to repress E-cadherin expression. HCV core protein inhibited ubiquitin-dependent proteasomal degradation of E12/E47 without affecting their expression at the transcriptional level. E12/E47 upregulation ultimately led to EMT in human hepatocytes, as demonstrated by morphological changes, altered expression levels of EMT markers, including E-cadherin, plakoglobin, and fibronectin, and increased capacity for cell detachment and migration. In conclusion, HCV core protein represses E-cadherin expression by upregulating E12/E47 levels to induce EMT in HCV-associated HCC.
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Affiliation(s)
- Indira Tiwari
- Department of Microbiology, College of Natural Sciences, Pusan National University, Busan 609-735, Republic of Korea
| | - Min-Ho Yoon
- Department of Molecular Biology, College of Natural Sciences, Pusan National University, Busan 609-735, Republic of Korea
| | - Bum-Joon Park
- Department of Molecular Biology, College of Natural Sciences, Pusan National University, Busan 609-735, Republic of Korea
| | - Kyung Lib Jang
- Department of Microbiology, College of Natural Sciences, Pusan National University, Busan 609-735, Republic of Korea.
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Gupta N, Wu CH, Wu GY. Secondary Structural Elements of the HCV X-region Involved in Viral Replication. J Clin Transl Hepatol 2015; 3:1-8. [PMID: 26356238 PMCID: PMC4542080 DOI: 10.14218/jcth.2015.00003] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/02/2015] [Revised: 02/26/2015] [Accepted: 03/01/2015] [Indexed: 12/16/2022] Open
Abstract
BACKGROUND AND AIMS The noncoding regions in the 3'-untranslated region (UTR) of the hepatitis C virus (HCV) genome contain secondary structures that are important for replication. The aim of this study was to identify detailed conformational elements of the X-region involved in HCV replication. METHODS Ribonucleic acid (RNA) structural analogs X94, X12, and X12c were constructed to have identical conformation but 94%, 12%, and 0% sequence identity, respectively, to the X region of HCV genotype 2a. Effects of structural analogs on replication of HCV genotypes 1b and 2a HCV RNA were studied by quantitative reverse transcriptase polymerase chain reaction. RESULTS In replicon BB7 cells, a constitutive replication model, HCV RNA levels decreased to 55%, 52%, 53%, and 54% after transfection with expression plasmids generating RNA structural analogs 5B-46, X-94, X-12, and X-12c, respectively (p<0.001 for all). In an HCV genotype 2a infection model, RNA analogs 5B-46, X-94, and X-12 in hepatic cells inhibited replication to 11%, 9%, and 12%, respectively. Because the X-12 analog was only 12% identical to the corresponding sequence of HCV genotype 2a, the sequence per se, or antisense effects were unlikely to be involved. CONCLUSIONS The data suggest that conformation of secondary structures in 3'-UTR of HCV RNA genome is required for HCV replication. Stable expression of RNA analogs predicted to have identical stem-loop structures might inhibit HCV infection of hepatocytes in liver and may represent a novel approach to design anti-HCV agents.
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Affiliation(s)
| | | | - George Y. Wu
- Correspondence to: George Y. Wu, Department of Medicine, Division of Gastroenterology-Hepatology, University of Connecticut Health Center, 263 Farmington Ave, Farmington, CT 06030-1845, USA. Tel: +1-800-535-6232; +1-860-679-7692, Fax: +1-860-679-3159. E-mail:
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30
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Yang C, Zhao X, Sun D, Yang L, Chong C, Pan Y, Chi X, Gao Y, Wang M, Shi X, Sun H, Lv J, Gao Y, Zhong J, Niu J, Sun B. Interferon alpha (IFNα)-induced TRIM22 interrupts HCV replication by ubiquitinating NS5A. Cell Mol Immunol 2015; 13:94-102. [PMID: 25683609 DOI: 10.1038/cmi.2014.131] [Citation(s) in RCA: 70] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2014] [Revised: 12/05/2014] [Accepted: 12/05/2014] [Indexed: 12/28/2022] Open
Abstract
TRIM22, a tripartite-motif (TRIM) protein, is upregulated upon interferon alpha (IFNα) administration to hepatitis C virus (HCV)-infected patients. However, the physiological role of TRIM22 upregulation remains unclear. Here, we describe a potential antiviral function of TRIM22's targeting of the HCV NS5A protein. NS5A is important for HCV replication and for resistance to IFNα therapy. During the first 24 h following the initiation of IFNα treatment, upregulation of TRIM22 in the peripheral blood mononuclear cells (PBMCs) of HCV patients correlated with a decrease in viral titer. This phenomenon was confirmed in the hepatocyte-derived cell line Huh-7, which is highly permissive for HCV infection. TRIM22 over-expression inhibited HCV replication, and Small interfering RNA (siRNA)-mediated knockdown of TRIM22 diminished IFNα-induced anti-HCV function. Furthermore, we determined that TRIM22 ubiquitinates NS5A in a concentration-dependent manner. In summary, our results suggest that TRIM22 upregulation is associated with HCV decline during IFNα treatment and plays an important role in controlling HCV replication in vitro.
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Affiliation(s)
- Chen Yang
- State Key Laboratory of Cell Biology, Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai, China
| | - Xinhao Zhao
- Key Laboratory of Molecular Virology and Immunology, Institut Pasteur of Shanghai, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai, China
| | - Dakang Sun
- Experiment Center of Clinical Medicine, Affiliated Hospital of Binzhou Medical University, Binzhou, China
| | - Leilei Yang
- Key Laboratory of Molecular Virology and Immunology, Institut Pasteur of Shanghai, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai, China
| | - Chang Chong
- Key Laboratory of Molecular Virology and Immunology, Institut Pasteur of Shanghai, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai, China
| | - Yu Pan
- Hepatology Section, First Hospital, University of Jilin, Changchun, China
| | - Xiumei Chi
- Hepatology Section, First Hospital, University of Jilin, Changchun, China
| | - Yanhang Gao
- Hepatology Section, First Hospital, University of Jilin, Changchun, China
| | - Moli Wang
- Infectious Diseases Department, Fourth Hospital, University of Jilin, Changchun, China
| | - Xiaodong Shi
- Hepatology Section, First Hospital, University of Jilin, Changchun, China
| | - Haibo Sun
- Hepatology Section, First Hospital, University of Jilin, Changchun, China
| | - Juan Lv
- Hepatology Section, First Hospital, University of Jilin, Changchun, China
| | - Yuanda Gao
- Hepatology Section, First Hospital, University of Jilin, Changchun, China
| | - Jin Zhong
- Key Laboratory of Molecular Virology and Immunology, Institut Pasteur of Shanghai, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai, China
| | - Junqi Niu
- Hepatology Section, First Hospital, University of Jilin, Changchun, China
| | - Bing Sun
- State Key Laboratory of Cell Biology, Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai, China.,Key Laboratory of Molecular Virology and Immunology, Institut Pasteur of Shanghai, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai, China
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Discovering novel anti-HCV compounds with inhibitory activities toward HCV NS3/4A protease. Acta Pharmacol Sin 2014; 35:1074-81. [PMID: 25066323 DOI: 10.1038/aps.2014.55] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2014] [Accepted: 05/22/2014] [Indexed: 11/09/2022] Open
Abstract
AIM To discover novel hepatitis C virus (HCV) inhibitors and elucidate the mechanism of action of the active compounds. METHODS HCV subgenomic replicon-based luciferase reporter cell line was used to screen 1200 synthetic compounds with novel structures. Huh7.5.1 cell line stably transfected with HCV NS3/4A protease reporter was established to investigate the anti-HCV mechanism of the active compounds. The active compounds were further examined in an in vitro HCV infection assay to confirm their anti-HCV activity. RESULTS After two-round screening in the anti-HCV replicon assay, some 2,4-diaminoquinazoline derivatives and carboxamide analogues were found to possess anti-HCV replicon activities (the IC50 values were less than 5 μmol/L). Among them, two representative compounds HZ-1157 and LZ-110618-6 inhibited HCV NS3/4A protease with IC50 values of 1.0 and 0.68 μmol/L, respectively. Furthermore, HZ-1157 and LZ-110618-6 inhibited HCV infection in vitro with IC50 values of 0.82 and 0.11 μmol/L, respectively. CONCLUSION Some 2,4-diaminoquinazoline derivatives and carboxamide analogues have been identified as novel anti-HCV compounds.
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Abdulrahman Almatrrouk S, Oliver AW, Hampson L, Hampson IN. Targeting gap junction intercellular communication as a potential therapy for HCV-related carcinogenesis. Future Virol 2014. [DOI: 10.2217/fvl.14.50] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
ABSTRACT: Worldwide, at least 170 million people are infected with hepatitis C virus (HCV), which is associated with hepatocellular carcinoma (HCC). With the recent success of Sofosbuvir (and other agents) antiviral therapy may be used as a future early-stage HCC treatment; however, in the short term, a cost-effective solution is needed to treat patients with viral-associated HCC. Here, we emphasize the potential of targeting gap junction intercellular communication (GJIC) as a therapeutic approach for HCC as HCV perturbs GJIC, which is linked to cellular transformation. We review the ROCK inhibitor Y-27632 and structurally related compounds that may inhibit the carcinogenic properties of HCV.
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Affiliation(s)
| | - Anthony W Oliver
- University of Manchester, Viral Oncology, Research Floor, St Mary's Hospital, Manchester, UK
| | - Lynne Hampson
- University of Manchester, Viral Oncology, Research Floor, St Mary's Hospital, Manchester, UK
| | - Ian N Hampson
- University of Manchester, Viral Oncology, Research Floor, St Mary's Hospital, Manchester, UK
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Kato N, Sejima H, Ueda Y, Mori K, Satoh S, Dansako H, Ikeda M. Genetic characterization of hepatitis C virus in long-term RNA replication using Li23 cell culture systems. PLoS One 2014; 9:e91156. [PMID: 24625789 PMCID: PMC3953375 DOI: 10.1371/journal.pone.0091156] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2013] [Accepted: 02/10/2014] [Indexed: 12/17/2022] Open
Abstract
BACKGROUND The most distinguishing genetic feature of hepatitis C virus (HCV) is its remarkable diversity and variation. To understand this feature, we previously performed genetic analysis of HCV in the long-term culture of human hepatoma HuH-7-derived HCV RNA-replicating cell lines. On the other hand, we newly established HCV RNA-replicating cell lines using human hepatoma Li23 cells, which were distinct from HuH-7 cells. METHODOLOGY/PRINCIPAL FINDINGS Li23-derived HCV RNA-replicating cells were cultured for 4 years. We performed genetic analysis of HCVs recovered from these cells at 0, 2, and 4 years in culture. Most analysis was performed in two separate parts: one part covered from the 5'-terminus to NS2, which is mostly nonessential for RNA replication, and the other part covered from NS3 to NS5B, which is essential for RNA replication. Genetic mutations in both regions accumulated in a time-dependent manner, and the mutation rates in the 5'-terminus-NS2 and NS3-NS5B regions were 4.0-9.0×10(-3) and 2.7-4.0×10(-3) base substitutions/site/year, respectively. These results suggest that the variation in the NS3-NS5B regions is affected by the pressure of RNA replication. Several in-frame deletions (3-105 nucleotides) were detected in the structural regions of HCV RNAs obtained from 2-year or 4-year cultured cells. Phylogenetic tree analyses clearly showed that the genetic diversity of HCV was expanded in a time-dependent manner. The GC content of HCV RNA was significantly increased in a time-dependent manner, as previously observed in HuH-7-derived cell systems. This phenomenon was partially due to the alterations in codon usages for codon optimization in human cells. Furthermore, we demonstrated that these long-term cultured cells were useful as a source for the selection of HCV clones showing resistance to anti-HCV agents. CONCLUSIONS/SIGNIFICANCE Long-term cultured HCV RNA-replicating cells are useful for the analysis of evolutionary dynamics and variations of HCV and for drug-resistance analysis.
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Affiliation(s)
- Nobuyuki Kato
- Department of Tumor Virology, Okayama University Graduate School of Medicine, Dentistry, and Pharmaceutical Sciences, Shikata-cho, Okayama, Japan
- * E-mail:
| | - Hiroe Sejima
- Department of Tumor Virology, Okayama University Graduate School of Medicine, Dentistry, and Pharmaceutical Sciences, Shikata-cho, Okayama, Japan
| | - Youki Ueda
- Department of Tumor Virology, Okayama University Graduate School of Medicine, Dentistry, and Pharmaceutical Sciences, Shikata-cho, Okayama, Japan
| | - Kyoko Mori
- Department of Tumor Virology, Okayama University Graduate School of Medicine, Dentistry, and Pharmaceutical Sciences, Shikata-cho, Okayama, Japan
| | - Shinya Satoh
- Department of Tumor Virology, Okayama University Graduate School of Medicine, Dentistry, and Pharmaceutical Sciences, Shikata-cho, Okayama, Japan
| | - Hiromichi Dansako
- Department of Tumor Virology, Okayama University Graduate School of Medicine, Dentistry, and Pharmaceutical Sciences, Shikata-cho, Okayama, Japan
| | - Masanori Ikeda
- Department of Tumor Virology, Okayama University Graduate School of Medicine, Dentistry, and Pharmaceutical Sciences, Shikata-cho, Okayama, Japan
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GP73 is upregulated by hepatitis C virus (HCV) infection and enhances HCV secretion. PLoS One 2014; 9:e90553. [PMID: 24608522 PMCID: PMC3946557 DOI: 10.1371/journal.pone.0090553] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2013] [Accepted: 01/31/2014] [Indexed: 12/17/2022] Open
Abstract
Hepatitis C virus (HCV) is a major cause of chronic liver disease. However, little is known about the details of its assembly and secretion. Golgi-related proteins have been recently proven to have a key function in HCV secretion. Golgi protein 73 (GP73), a resident Golgi membrane protein, is a potential serum biomarker for the diagnosis of liver diseases and hepatocellular carcinoma. Previous studies have demonstrated the upregulation of GP73 in the liver samples and sera of HCV-infected patients. However, the function and regulatory mechanism of GP73 in HCV infection at the cellular level remain unknown. In this study, we examined the expression level of GP73 in HCV infected cells and its effect on HCV life cycle in cell culture systems. Both the protein expression and mRNA levels of GP73 significantly increased in HCV subgenomic replicon-harboring cells and HCV-infected cells, which imply that GP73 was upregulated by HCV infection. HCV production was significantly enhanced when GP73 was overexpressed, but dramatically inhibited when GP73 was silenced. However, the overexpression and knockdown of GP73 showed no evident effect on the entry, protein translation, RNA replication, and assembly of HCV, which indicates that GP73 enhanced the secretion process. Moreover, the coiled-coil domain of GP73 was required to increase HCV secretion. GP73 increased and interacted with apolipoprotein E, an identified host factor that assists in HCV secretion. These results demonstrate the critical function of GP73 in HCV secretion and provide new insights into the therapeutic design of antiviral strategies.
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35
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Hadinedoushan H, Salmanroghani H, Amirbaigy MK, Akhondi-Meybodi M. Hepatitis C virus genotypes and association with viral load in yazd, central province of iran. HEPATITIS MONTHLY 2014; 14:e11705. [PMID: 24693314 PMCID: PMC3955264 DOI: 10.5812/hepatmon.11705] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 04/21/2013] [Revised: 11/30/2013] [Accepted: 01/10/2014] [Indexed: 12/11/2022]
Abstract
BACKGROUND Hepatitis C virus (HCV) is a major cause of liver disease. Infection with HCV is a global public health problem. The virus is classified into 6 genotypes and more than 80 subtypes named as a, b, c, etc. HCV genotyping has been an important parameter for the treatment of HCV infection. OBJECTIVES The main aim of this study was to estimate the prevalence of HCV genotypes in Yazd, central province of Iran. In addition, the study investigated whether there was any association between HCV load and genotypes. PATIENTS AND METHODS This descriptive cross-sectional study was performed on samples suspicious of HCV infection from March 2010 to June 2013. Peripheral blood sample was obtained and screened for anti-HCV antibodies using Enzyme-Linked Immunosorbent Assay (ELISA). Then sera of anti-HCV positive samples were analyzed using quantitative polymerase chain reaction method. Plasma samples were used to determine the HCV genotypes of 1a, 1b, 2, 3, and 4 in 191 infected patients. RESULTS One hundred fifty-two out of 191 (79.6%) samples were from male patients. The mean of the patients' age was 40.7 ± 11.9 years (range 21-75 years old). Sixty- three (33%) patients were included in 31-40 years group. The mean number of HCV in infected patients was 2.92 × 10(6) ± 1.85 × 10(6) copies/mL (Min: 508; Max: 2.75 × 10(8) copies/mL). HCV genotype 3 was the predominant genotype (50.3%) followed by subtypes 1a (38.7%) and 1b (6.8%). The distribution of other HCV genotypes showed genotype 2 in 1.6% and mixed genotypes in 2.6% of positive samples. Genotype 3 was predominant in all age groups except 21-30 years of age group. We were unable to find any significant difference between mean viral load of the patients infected with genotype 3 and those infected with genotype 1 (1a and 1b). CONCLUSIONS Findings of the present study showed that HCV genotype 3 was the predominant genotype followed by the subtypes 1a and 1b in Yazd, central province of Iran. In addition, there was no difference between HCV load and genotypes 1 and 3. HCV genotyping is recommended in other provinces of Iran.
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Affiliation(s)
- Hossein Hadinedoushan
- Immunology Department, Faculty of Medicine, Shahid Sadoughi University of Medical Sciences, Yazd, IR Iran
- Corresponding Author: Hossein Hadinedoushan, Immunology Department, Faculty of Medicine, Shahid Sadoughi University of Medical Sciences, Daneshjou Blv, Yazd, IR Iran. Tel: +98-3516233235, Fax: +98-3516238561, E-mail:
| | - Hasan Salmanroghani
- Gastrology Department, Faculty of Medicine, Shahid Sadoughi Hospital, Shahid Sadoughi University of Medical Sciences, Yazd, IR Iran
| | - Mohammad Kazem Amirbaigy
- Gastrology Department, Faculty of Medicine, Shahid Sadoughi Hospital, Shahid Sadoughi University of Medical Sciences, Yazd, IR Iran
| | - Mohsen Akhondi-Meybodi
- Gastrology Department, Faculty of Medicine, Shahid Sadoughi Hospital, Shahid Sadoughi University of Medical Sciences, Yazd, IR Iran
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Specific sequence of a Beta turn in human la protein may contribute to species specificity of hepatitis C virus. J Virol 2014; 88:4319-27. [PMID: 24478427 DOI: 10.1128/jvi.00049-14] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
UNLABELLED Human La protein is known to be an essential host factor for translation and replication of hepatitis C virus (HCV) RNA. Previously, we have demonstrated that residues responsible for interaction of human La protein with the HCV internal ribosomal entry site (IRES) around the initiator AUG within stem-loop IV form a β-turn in the RNA recognition motif (RRM) structure. In this study, sequence alignment and mutagenesis suggest that the HCV RNA-interacting β-turn is conserved only in humans and chimpanzees, the species primarily known to be infected by HCV. A 7-mer peptide corresponding to the HCV RNA-interacting region of human La inhibits HCV translation, whereas another peptide corresponding to the mouse La sequence was unable to do so. Furthermore, IRES-mediated translation was found to be significantly high in the presence of recombinant human La protein in vitro in rabbit reticulocyte lysate. We observed enhanced replication with HCV subgenomic and full-length replicons upon overexpression of either human La protein or a chimeric mouse La protein harboring a human La β-turn sequence in mouse cells. Taken together, our results raise the possibility of creating an immunocompetent HCV mouse model using human-specific cell entry factors and a humanized form of La protein. IMPORTANCE Hepatitis C virus is known to infect only humans and chimpanzees under natural conditions. This has prevented the development of a small-animal model, which is important for development of new antiviral drugs. Although a number of human-specific proteins are responsible for this species selectivity and some of these proteins--mostly entry factors--have been identified, full multiplication of the virus in mouse cells is still not possible. In this study, we show that a turn in the human La protein that is responsible for the interaction with the viral RNA is highly specific for the human sequence. Replacement of the corresponding mouse sequence with the human sequence allows the mouse La to behave like its human counterpart and support viral growth in the mouse cell efficiently. This observation, in combination with previously identified cell entry factors, should open up the possibility of creating a mouse model of hepatitis C.
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Zhou JJ, Chen RF, Deng XG, Zhou Y, Ye X, Yu M, Tang J, He XY, Cheng D, Zeng B, Zhou QB, Li ZH. Hepatitis C virus core protein regulates NANOG expression via the stat3 pathway. FEBS Lett 2014; 588:566-73. [PMID: 24462277 DOI: 10.1016/j.febslet.2013.11.041] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2013] [Revised: 11/20/2013] [Accepted: 11/25/2013] [Indexed: 12/20/2022]
Abstract
HCV Core plays a role in the development of hepatocellular carcinoma. Aberrant expression of NANOG has been observed in many types of human malignancies. However, relationship between Core and NANOG has not been clarified. In this study, we found that Core is capable of up-regulating NANOG expression. Core-induced NANOG expression was accompanied by enforced expression of phosphorylated stat3 protein and was attenuated by inhibition of stat3 phosphorylation. ChIP showed that phosphorylated stat3 directly binds to the NANOG promoter. Core-induced NANOG expression resulted in enhanced cell growth and cell cycle progression. Knockdown of NANOG blocked the cell cycle at the G0/G1 phases and inhibited the cyclin D1 expression. Our findings provide a new insight into the mechanism of hepatocarcinogenesis by HCV infection.
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Affiliation(s)
- Jia-Jia Zhou
- Department of Surgery, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, Guangdong Province, China.
| | - Ru-Fu Chen
- Department of Surgery, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, Guangdong Province, China; Department of Oncology, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, Guangdong Province, China
| | - Xiao-Geng Deng
- Department of Surgery, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, Guangdong Province, China
| | - Yu Zhou
- Department of Surgery, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, Guangdong Province, China
| | - Xiao Ye
- Department of Surgery, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, Guangdong Province, China
| | - Min Yu
- Department of Surgery, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, Guangdong Province, China
| | - Jing Tang
- Department of Surgery, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, Guangdong Province, China
| | - Xiao-Yu He
- Laboratory of Biomechanics and Physiology, Guangdong Provincial Institute of Sports Science, Guangzhou, Guangdong Province, China
| | - Di Cheng
- Department of Surgery, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, Guangdong Province, China
| | - Bing Zeng
- Department of Surgery, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, Guangdong Province, China
| | - Quan-bo Zhou
- Department of Surgery, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, Guangdong Province, China; Department of Oncology, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, Guangdong Province, China
| | - Zhi-hua Li
- Department of Oncology, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, Guangdong Province, China
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Hundt J, Li Z, Liu Q. Post-translational modifications of hepatitis C viral proteins and their biological significance. World J Gastroenterol 2013; 19:8929-8939. [PMID: 24379618 PMCID: PMC3870546 DOI: 10.3748/wjg.v19.i47.8929] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/18/2013] [Accepted: 12/04/2013] [Indexed: 02/06/2023] Open
Abstract
Replication of hepatitis C virus (HCV) depends on the interaction of viral proteins with various host cellular proteins and signalling pathways. Similar to cellular proteins, post-translational modifications (PTMs) of HCV proteins are essential for proper protein function and regulation, thus, directly affecting viral life cycle and the generation of infectious virus particles. Cleavage of the HCV polyprotein by cellular and viral proteases into more than 10 proteins represents an early protein modification step after translation of the HCV positive-stranded RNA genome. The key modifications include the regulated intramembranous proteolytic cleavage of core protein, disulfide bond formation of core, glycosylation of HCV envelope proteins E1 and E2, methylation of nonstructural protein 3 (NS3), biotinylation of NS4A, ubiquitination of NS5B and phosphorylation of core and NS5B. Other modifications like ubiquitination of core and palmitoylation of core and NS4B proteins have been reported as well. For some modifications such as phosphorylation of NS3 and NS5A and acetylation of NS3, we have limited understanding of their effects on HCV replication and pathogenesis while the impact of other modifications is far from clear. In this review, we summarize the available information on PTMs of HCV proteins and discuss their relevance to HCV replication and pathogenesis.
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Lee J. Cyclophilin A as a New Therapeutic Target for Hepatitis C Virus-induced Hepatocellular Carcinoma. THE KOREAN JOURNAL OF PHYSIOLOGY & PHARMACOLOGY : OFFICIAL JOURNAL OF THE KOREAN PHYSIOLOGICAL SOCIETY AND THE KOREAN SOCIETY OF PHARMACOLOGY 2013; 17:375-83. [PMID: 24227937 PMCID: PMC3823949 DOI: 10.4196/kjpp.2013.17.5.375] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/28/2013] [Revised: 09/21/2013] [Accepted: 09/23/2013] [Indexed: 12/24/2022]
Abstract
Hepatocellular carcinoma (HCC) related to hepatitis B virus (HBV) and hepatitis C virus (HCV) infections is thought to account for more than 80% of primary liver cancers. Both HBV and HCV can establish chronic liver inflammatory infections, altering hepatocyte and liver physiology with potential liver disease progression and HCC development. Cyclophilin A (CypA) has been identified as an essential host factor for the HCV replication by physically interacting with the HCV non structural protein NS5A that in turn interacts with RNA-dependent RNA polymerase NS5B. CypA, a cytosolic binding protein of the immunosuppressive drug cyclosporine A, is overexpressed in many cancer types and often associated with malignant transformation. Therefore, CypA can be a good target for molecular cancer therapy. Because of antiviral activity, the CypA inhibitors have been tested for the treatment of chronic hepatitis C. Nonimmunosuppressive Cyp inhibitors such as NIM811, SCY-635, and Alisporivir have attracted more interests for appropriating CypA for antiviral chemotherapeutic target on HCV infection. This review describes CypA inhibitors as a potential HCC treatment tool that is contrived by their obstructing chronic HCV infection and summarizes roles of CypA in cancer development.
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Affiliation(s)
- Jinhwa Lee
- Department of Clinical Lab Science, School of Health Science, Dongseo University, Busan 617-716, Korea
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Suzuki R, Matsuda M, Watashi K, Aizaki H, Matsuura Y, Wakita T, Suzuki T. Signal peptidase complex subunit 1 participates in the assembly of hepatitis C virus through an interaction with E2 and NS2. PLoS Pathog 2013; 9:e1003589. [PMID: 24009510 PMCID: PMC3757040 DOI: 10.1371/journal.ppat.1003589] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2013] [Accepted: 07/19/2013] [Indexed: 12/12/2022] Open
Abstract
Hepatitis C virus (HCV) nonstructural protein 2 (NS2) is a hydrophobic, transmembrane protein that is required not only for NS2-NS3 cleavage, but also for infectious virus production. To identify cellular factors that interact with NS2 and are important for HCV propagation, we screened a human liver cDNA library by split-ubiquitin membrane yeast two-hybrid assay using full-length NS2 as a bait, and identified signal peptidase complex subunit 1 (SPCS1), which is a component of the microsomal signal peptidase complex. Silencing of endogenous SPCS1 resulted in markedly reduced production of infectious HCV, whereas neither processing of structural proteins, cell entry, RNA replication, nor release of virus from the cells was impaired. Propagation of Japanese encephalitis virus was not affected by knockdown of SPCS1, suggesting that SPCS1 does not widely modulate the viral lifecycles of the Flaviviridae family. SPCS1 was found to interact with both NS2 and E2. A complex of NS2, E2, and SPCS1 was formed in cells as demonstrated by co-immunoprecipitation assays. Knockdown of SPCS1 impaired interaction of NS2 with E2. Our findings suggest that SPCS1 plays a key role in the formation of the membrane-associated NS2-E2 complex via its interaction with NS2 and E2, which leads to a coordinating interaction between the structural and non-structural proteins and facilitates the early step of assembly of infectious particles. Viruses hijack host cells and utilize host-derived proteins for viral propagation. In the case of hepatitis C virus (HCV), many host factors have been identified that are required for genome replication; however, only a little is known about cellular proteins that interact with HCV proteins and are important for the viral assembly process. The C-terminal half of nonstructural protein 2 (NS2), and the N-terminal third of NS3, form the NS2-3 protease that cleaves the NS2/3 junction. NS2 also plays a key role in the viral assembly process independently of the protease activity. We performed split-ubiquitin yeast two-hybrid screening and identified signal peptidase complex subunit 1 (SPCS1), which is a subunit of the microsomal signal peptidase complex. In this study, we provide evidence that SPCS1 interacts with both NS2 and E2, resulting in E2-SPCS1-NS2 complex formation, and has a critical role in the assembly of infectious HCV particles. To our knowledge, SPCS1 is the first NS2-interacting cellular factor that is involved in regulation of the HCV lifecycle.
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Affiliation(s)
- Ryosuke Suzuki
- Department of Virology II, National Institute of Infectious Diseases, Tokyo, Japan
- * E-mail: (RS); (TS)
| | - Mami Matsuda
- Department of Virology II, National Institute of Infectious Diseases, Tokyo, Japan
| | - Koichi Watashi
- Department of Virology II, National Institute of Infectious Diseases, Tokyo, Japan
| | - Hideki Aizaki
- Department of Virology II, National Institute of Infectious Diseases, Tokyo, Japan
| | - Yoshiharu Matsuura
- Research Institute for Microbial Diseases, Osaka University, Osaka, Japan
| | - Takaji Wakita
- Department of Virology II, National Institute of Infectious Diseases, Tokyo, Japan
| | - Tetsuro Suzuki
- Department of Infectious Diseases, Hamamatsu University School of Medicine, Shizuoka, Japan
- * E-mail: (RS); (TS)
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41
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Read SA, Douglas MW. Virus induced inflammation and cancer development. Cancer Lett 2013; 345:174-81. [PMID: 23941825 DOI: 10.1016/j.canlet.2013.07.030] [Citation(s) in RCA: 50] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2013] [Revised: 07/19/2013] [Accepted: 07/28/2013] [Indexed: 12/12/2022]
Abstract
Chronic inflammation as a result of viral infection significantly increases the likelihood of cancer development. A handful of diverse viruses have confirmed roles in cancer development and progression, but the list of suspected oncogenic viruses is continually growing. Viruses induce cancer directly and indirectly, by activating inflammatory signalling pathways and cytokines, stimulating growth of infected cells and inhibiting apoptosis. Although oncogenic viruses induce inflammation by various mechanisms, it is generally mediated by the MAPK, NFκB and STAT3 signalling pathways. This review will explore the unique mechanisms by which different oncogenic viruses induce inflammation to promote cancer initiation and progression.
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Affiliation(s)
- Scott A Read
- Storr Liver Unit, Westmead Millennium Institute, University of Sydney at Westmead Hospital, Sydney, Australia
| | - Mark W Douglas
- Storr Liver Unit, Westmead Millennium Institute, University of Sydney at Westmead Hospital, Sydney, Australia; Centre for Infectious Diseases and Microbiology, Marie Bashir Institute for Infectious Diseases and Biosecurity University of Sydney at Westmead Hospital, Sydney, Australia.
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Human La protein interaction with GCAC near the initiator AUG enhances hepatitis C Virus RNA replication by promoting linkage between 5' and 3' untranslated regions. J Virol 2013; 87:6713-26. [PMID: 23552417 DOI: 10.1128/jvi.00525-13] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Human La protein has been implicated in facilitating the internal initiation of translation as well as replication of hepatitis C virus (HCV) RNA. Previously, we demonstrated that La interacts with the HCV internal ribosome entry site (IRES) around the GCAC motif near the initiator AUG within stem-loop IV by its RNA recognition motif (RRM) (residues 112 to 184) and influences HCV translation. In this study, we have deciphered the role of this interaction in HCV replication in a hepatocellular carcinoma cell culture system. We incorporated mutation of the GCAC motif in an HCV monocistronic subgenomic replicon and a pJFH1 construct which altered the binding of La and checked HCV RNA replication by reverse transcriptase PCR (RT-PCR). The mutation drastically affected HCV replication. Furthermore, to address whether the decrease in replication is a consequence of translation inhibition or not, we incorporated the same mutation into a bicistronic replicon and observed a substantial decrease in HCV RNA levels. Interestingly, La overexpression rescued this inhibition of replication. More importantly, we observed that the mutation reduced the association between La and NS5B. The effect of the GCAC mutation on the translation-to-replication switch, which is regulated by the interplay between NS3 and La, was further investigated. Additionally, our analyses of point mutations in the GCAC motif revealed distinct roles of each nucleotide in HCV replication and translation. Finally, we showed that a specific interaction of the GCAC motif with human La protein is crucial for linking 5' and 3' ends of the HCV genome. Taken together, our results demonstrate the mechanism of regulation of HCV replication by interaction of the cis-acting element GCAC within the HCV IRES with human La protein.
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Li G, Li K, Lea AS, Li NL, Abdulla NE, Eltorky MA, Ferguson MR. In situ hybridization for the detection of hepatitis C virus RNA in human liver tissue. J Viral Hepat 2013; 20:183-92. [PMID: 23383657 DOI: 10.1111/j.1365-2893.2012.01642.x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/01/2012] [Accepted: 05/01/2012] [Indexed: 12/11/2022]
Abstract
In situ hybridization (ISH) enables visualization of specific nucleic acid in morphologically preserved cells and tissue sections. Detection of the HCV genomes in clinical specimens is useful for differential diagnosis, particularly between recurrent HCV infection and acute cellular rejection in transplant specimens. We optimized an ISH protocol that demonstrated sensitivity and specificity for detecting genomic and replicative form of HCV RNA in tissue biopsies. Digoxigenin (Dig)-labelled sense and anti-sense riboprobes were synthesized using a plasmid containing a fragment of the highly conserved HCV noncoding region as a template. The efficiency of the Dig-labelled riboprobes in detecting genomic and replicative-intermediate HCV RNA was analysed in 30 liver biopsies from patients infected or uninfected with HCV in a blinded study. A Huh7 cell line that stably replicates genome-length HCV RNA was developed to be used as a positive control. Negative control riboprobes were used in parallel to evaluate and control for background staining. The anti-sense probe detected HCV RNA in 20/21 specimens from HCV-infected liver tissues obtained from patients and in 0/9 samples from patients with non-HCV-related liver diseases, resulting in a sensitivity and specificity of 95% and 100%, respectively. HCV genomic RNA was variably distributed in tissue sections and was located primarily in the perinuclear regions in hepatocytes. Detection of HCV RNA by our optimized ISH protocol appears to be a sensitive and specific method when processing clinical specimens. It may also be revealing when exploring the pathophysiology of HCV infection by verifying the presence of viral genetic material within heptocytes and other cellular elements of diseased liver tissue. This methodology might also evaluate the response to antiviral therapies by demonstrating the absence or alteration of genetic material in clinical specimens from successfully treated patients.
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Affiliation(s)
- G Li
- Division of Infectious Diseases, Department of Internal Medicine, University of Texas Medical Branch, Galveston, TX 77555, USA.
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Marton S, Romero-López C, Berzal-Herranz A. RNA aptamer-mediated interference of HCV replication by targeting the CRE-5BSL3.2 domain. J Viral Hepat 2013; 20:103-12. [PMID: 23301545 DOI: 10.1111/j.1365-2893.2012.01629.x] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
The RNA genome of hepatitis C virus (HCV) contains multiple conserved structural RNA domains that play key roles in essential viral processes. A conserved structural component within the 3' end of the region coding for viral RNA-dependent RNA polymerase (NS5B) has been characterized as a functional cis-acting replication element (CRE). This study reports the ability of two RNA aptamers, P-58 and P-78, to interfere with HCV replication by targeting the essential 5BSL3.2 domain within this CRE. Structure-probing assays showed the binding of the aptamers to the CRE results in a structural reorganization of the apical portion of the 5BSL3.2 stem-loop domain. This interfered with the binding of the NS5B protein to the CRE and induced a significant reduction in HCV replication (≈50%) in an autonomous subgenomic HCV replication system. These results highlight the potential of this CRE as a target for the development of anti-HCV therapies and underscore the potential of antiviral agents based on RNA aptamer molecules.
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Affiliation(s)
- S Marton
- Instituto de Parasitología y Biomedicina López-Neyra, IPBLN-CSIC, Parque Tecnológico de Ciencias de la Salud, Granada, Spain
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Abozaid SM, Shoukri M, Al-Qahtani A, Al-Ahdal MN. Prevailing genotypes of hepatitis C virus in Saudi Arabia: a systematic analysis of evidence. Ann Saudi Med 2013; 33:1-5. [PMID: 23458931 PMCID: PMC6078584 DOI: 10.5144/0256-4947.2013.1] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/15/2023] Open
Abstract
BACKGROUND AND OBJECTIVES Although hepatitis C virus (HCV) genotype 4 has been reported to be prevalent in some countries of the Middle East, the genotype distribution in some geographical areas is not conclusive. We aimed to perform a meta-analysis on available literature on this issue in an attempt to identify or confirm the prevailing HCV genotypes in Saudi Arabia. METHODS We searched for reports describing genotypes in Saudi Arabia. A meta-analysis was performed on the samples in 18 studies, published between 1995 and 2011, in which HCV genotypes were identified. RESULTS A total of 2277 specimens from 18 studies showed that 617, 82, 119 and 1198 subjects were HCV-positive for genotypes 1, 2, 3 and 4, respectively. The meta-analyses showed that there is a great deal of heterogeneity in estimated prevalence among the studies. The highest prevalence was found in genotype HCV-4, followed by HCV-1, HCV-3, and HCV-2. CONCLUSION Our meta-analysei emphasizes that HCV genotype 4 is the most prevalent, followed by genotype 1. Further studies on genotype determination and subtype distribution are warranted.
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Affiliation(s)
- Suhair M Abozaid
- Department of Infection and Immunity, King Faisal Specialist Hospital and Research Centre, Riyadh, Saudi Arabia
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46
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Selimovic D, El-Khattouti A, Ghozlan H, Haikel Y, Abdelkader O, Hassan M. Hepatitis C virus-related hepatocellular carcinoma: An insight into molecular mechanisms and therapeutic strategies. World J Hepatol 2012; 4:342-55. [PMID: 23355912 PMCID: PMC3554798 DOI: 10.4254/wjh.v4.i12.342] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/21/2012] [Revised: 11/17/2012] [Accepted: 11/24/2012] [Indexed: 02/06/2023] Open
Abstract
Hepatitis C virus (HCV) infects more than 170 million people worldwide, and thereby becomes a series global health challenge. Chronic infection with HCV is considered one of the major causes of end-stage liver disease including cirrhosis and hepatocellular carcinoma. Although the multiple functions of the HCV proteins and their impacts on the modulation of the intracellular signaling transduction processes, the drive of carcinogenesis during the infection with HCV, is thought to result from the interactions of viral proteins with host cell proteins. Thus, the induction of mutator phenotype, in liver, by the expression of HCV proteins provides a key mechanism for the development of HCV-associated hepatocellular carcinoma (HCC). HCC is considered one of the most common malignancies worldwide with increasing incidence during the past decades. In many countries, the trend of HCC is attributed to several liver diseases including HCV infection. However, the development of HCC is very complicated and results mainly from the imbalance between tumor suppressor genes and oncogenes, as well as from the alteration of cellular factors leading to a genomic instability. Besides the poor prognosis of HCC patients, this type of tumor is quite resistance to the available therapies. Thus, understanding the molecular mechanisms, which are implicated in the development of HCC during the course of HCV infection, may help to design a general therapeutic protocol for the treatment and/or the prevention of this malignancy. This review summarizes the current knowledge of the molecular mechanisms, which are involved in the development of HCV-associated HCC and the possible therapeutic strategies.
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Affiliation(s)
- Denis Selimovic
- Denis Selimovic, Youssef Haikel, Mohamed Hassan, Institut National de la Santé et de la Recherche Médicale, U 977, 67000 Strasbourg, France
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An HY, Kim GN, Wu K, Kang CY. Genetically modified VSV(NJ) vector is capable of accommodating a large foreign gene insert and allows high level gene expression. Virus Res 2012. [PMID: 23207069 DOI: 10.1016/j.virusres.2012.11.007] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
It is desirable to develop a RNA virus vector capable of accommodating large foreign genes for high level gene expression. Vesicular stomatitis virus (VSV) has been used as a gene expression vector, especially Indiana serotype (VSV(Ind)), but less with New Jersey serotype (VSV(NJ)). Here, we report constructions of genetically modified rVSV(NJ) vector carrying various lengths of human hepatitis C virus (HCV) non-structural (NS) protein genes, level of inserted gene expression and characterization of rVSV(NJ). We modified the M gene of VSV(NJ) by changing methionine to arginine at positions 48 and 51 (rVSV(NJ)-M) (Kim and Kang, 2007) for construction of rVSV(NJ) with various lengths of HCV non-structural genes. The NS polyprotein genes of HCV were inserted between the G and L genes of the rVSV(NJ)-M vector, and recombinant VSV(NJ)-M viruses with HCV gene inserts were recovered by the reverse genetics. The recombinant VSV(NJ)-M vector with the HCV NS genes express high levels of all different forms of the NS proteins. The electron microscopic examination showed that lengths of recombinant VSV(NJ)-M without gene of interests, VSV(NJ)-M with a gene of HCV NS3 and NS4A (VSV(NJ)-M-NS3/4A), VSV(NJ)-M with a gene of HCV NS4AB plus NS5AB (VSV(NJ)-M-NS4AB/5AB), and VSV(NJ)-M carrying a gene of HCV NS3, NS4AB, and NS5AB (VSV(NJ)-M-NS3/4AB/5AB) were 172±10.5 nm, 201±12.5 nm, 226±12.9 nm, and 247±18.2 nm, respectively. The lengths of recombinant VSVs increased approximately 10nm by insertion of 1kb of foreign genes. The diameter of these recombinant viruses also increased slightly by longer HCV gene inserts. Our results showed that the recombinant VSV(NJ)-M vector can accommodate as much as 6000 bases of the foreign gene. We compared the magnitude of the IFN induction in mouse fibroblast L(Y) cells infected with rVSV(NJ) wild type and rVSV(NJ) M mutant viruses and show that the rVSV(NJ) M mutant virus infection induced a higher level of the IFN-β compare to the wild type virus. In addition, we showed that the NS protein expression level in IFN-incompetent cells (Mouse-L) infected with rVSV(NJ)-M viruses was higher than in IFN-competent L(Y) cells. In addition, we confirmed that HCV NS protein genes were expressed and properly processed. We also confirmed that NS3 protein expressed from the rVSV(NJ)-M cleaves NS polyprotein at junctions and that NS4A plays an important role as a co-factor for NS3 protease to cleave at the NS4B/5A site and at the NS5A/5B site.
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Affiliation(s)
- Hwa-Yong An
- Department of Microbiology and Immunology, Schulich School of Medicine and Dentistry, Siebens-Drake Research Institute, Western University, London, ON N6G 2V4, Canada
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Nakashima K, Takeuchi K, Chihara K, Horiguchi T, Sun X, Deng L, Shoji I, Hotta H, Sada K. HCV NS5A protein containing potential ligands for both Src homology 2 and 3 domains enhances autophosphorylation of Src family kinase Fyn in B cells. PLoS One 2012; 7:e46634. [PMID: 23077515 PMCID: PMC3473057 DOI: 10.1371/journal.pone.0046634] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2012] [Accepted: 09/02/2012] [Indexed: 01/24/2023] Open
Abstract
Hepatitis C virus (HCV) infects B lymphocytes and induces mixed cryoglobulinemia and B cell non-Hodgkin's lymphoma. The molecular mechanism for the pathogenesis of HCV infection-mediated B cell disorders remains obscure. To identify the possible role for HCV nonstructural 5A (NS5A) protein in B cells, we generated the stable B cell lines expressing Myc-His tagged NS5A. Immunoprecipitation study in the presence or absence of pervanadate (PV) implied that NS5A was tyrosine phosphorylated by pervanadate (PV) treatment of the cells. Therefore we examined pull-down assay by using glutathione S-transferase (GST)-fusion proteins of various Src homology 2 (SH2) domains, which associates with phosphotyrosine within a specific amino acid sequence. The results showed that NS5A specifically bound to SH2 domain of Fyn from PV-treated B cells in addition to Src homology 3 (SH3) domain. Substitution of Arg176 to Lys in the SH2 domain of Fyn abrogated this interaction. Deletion mutational analysis demonstrated that N-terminal region of NS5A was not required for the interaction with the SH2 domain of Fyn. Tyr334 was identified as a tyrosine phosphorylation site in NS5A. Far-western analysis revealed that SH2 domain of Fyn directly bound to NS5A. Fyn and NS5A were colocalized in the lipid raft. These results suggest that NS5A directly binds to the SH2 domain of Fyn in a tyrosine phosphorylation-dependent manner. Lastly, we showed that the expression of NS5A in B cells increased phosphorylation of activation loop tyrosine in the kinase domain of Fyn. NS5A containing ligand for both SH2 and SH3 domains enhances an aberrant autophosphorylation and kinase activity of Fyn in B cells.
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Affiliation(s)
- Kenji Nakashima
- Division of Genome Science and Microbiology, Department of Pathological Sciences, School of Medicine, Faculty of Medical Sciences, University of Fukui, Eiheiji, Japan
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Hussain S, Barretto N, Uprichard SL. New hepatitis C virus drug discovery strategies and model systems. Expert Opin Drug Discov 2012; 7:849-59. [PMID: 22861052 DOI: 10.1517/17460441.2012.711312] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
INTRODUCTION Hepatitis C virus (HCV) is a major cause of liver disease worldwide and the leading indication for liver transplantation in the United States. Current treatment options are expensive, not effective in all patients and are associated with serious side effects. Although preclinical, anti-HCV drug screening is still hampered by the lack of readily infectable small animal models, the development of cell culture HCV experimental model systems has driven a promising new wave of HCV antiviral drug discovery. AREAS COVERED This review contains a concise overview of current HCV treatment options and limitations with a subsequent in-depth focus on the available experimental models and novel strategies that have, and continue to enable, important advances in HCV drug development. EXPERT OPINION With a large cohort of chronically HCV-infected patients progressively developing liver disease that puts them at risk for hepatocellular carcinoma and hepatic decompensation, there is an urgent need to develop effective therapeutics that are well tolerated and effective in all patients and against all HCV genotypes. Significant advances in HCV experimental model development have expedited drug discovery; however, additional progress is needed. Importantly, the current trends and momentum in the field suggests that we will continue to overcome critical experimental challenges to reach this end goal.
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Affiliation(s)
- Snawar Hussain
- University of Illinois at Chicago, Department of Medicine, Chicago, IL 60612, USA
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50
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Zhao P, Han T, Guo JJ, Zhu SL, Wang J, Ao F, Jing MZ, She YL, Wu ZH, Ye LB. HCV NS4B induces apoptosis through the mitochondrial death pathway. Virus Res 2012; 169:1-7. [PMID: 22542667 DOI: 10.1016/j.virusres.2012.04.006] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2011] [Revised: 04/03/2012] [Accepted: 04/11/2012] [Indexed: 02/07/2023]
Abstract
The hepatitis C virus (HCV) NS4B protein is known to induce the formation of a membranous web that is thought to be the site of viral RNA replication. However, the exact functions of NS4B remain poorly characterized. In this study, we found that NS4B induced apoptosis in 293T cells and Huh7 cells, as confirmed by Hoechst staining, DNA fragmentation, and annexin V/PI assays. Furthermore, protein immunoblot analysis demonstrated that NS4B triggered the cleavage of caspase 3, caspase 7, and poly(ADP-ribose) polymerase (PARP). Further studies revealed that NS4B induced the activation of caspase 9, the reduction of mitochondrial membrane potential and the release of cytochrome c from the mitochondria. However, NS4B expression did not trigger XBP1 mRNA splicing and increase the expression of binding immunoglobulin protein (BiP, or GRP78) and C/EBP homologous protein (CHOP), which serves as the indicators of ER stress. Taken together, our results suggest that HCV NS4B induces apoptosis through the mitochondrial death pathway.
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Affiliation(s)
- Peng Zhao
- State Key Laboratory of Virology, College of Life Sciences, Wuhan University, Wuhan 430072, PR China
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