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1
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Hou H, Liang L, Deng L, Ye W, Wen Y, Liu J. Comparison of Clinical Manifestations and Related Factors of Hepatocellular Carcinoma with Chronic Hepatitis B. Int J Gen Med 2024; 17:2877-2886. [PMID: 38947567 PMCID: PMC11214568 DOI: 10.2147/ijgm.s464083] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2024] [Accepted: 06/18/2024] [Indexed: 07/02/2024] Open
Abstract
Background The aim of this study was to describe the demographic and clinical characteristics of hepatitis B virus (HBV) associated hepatocellular carcinoma (HCC), analyse the risk factors associated with HBV-associated HCC, and to provide some references to the diagnosis and treatment of HCC. Methods This study retrospectively enrolled 730 patients, including 390 patients with chronic hepatitis B (CHB) as controls, and 340 patients with CHB complicated with HCC as patients. Relevant information and medical records of these participants were collected, including age, sex, cigarette smoking, alcoholism, diabetes mellitus (DM), hypertension, coronary heart disease (CHD), cirrhosis, occupation, ascites, HBV-DNA load, the qualitative analysis of HBsAg, HBsAb, HBeAg, HBeAb, and HBcAb serological markers, and levels of alanine transaminase (ALT), aspartate aminotransferase (AST), total bilirubin (TBIL), direct bilirubin (DBIL), gamma-glutamyltransferase (GGT), TNM stage, tumor size and tumor number. The T test, Chi-square test, non-parametric rank-sum test, logistic regression analyses were used to explore the influencing factors and their degree of association with HCC in patients with HBV. Results The proportion of smoking, alcoholism, married status, DM, hypertension, and the rate of HBV-DNA with a viral load of ≥500 copies/mL were significantly higher in the HCC group than in the controls (all p<0.05). Cirrhosis was more common among patients with CHB+HCC than in controls (p=0.013). The proportion of patients with HBsAg, HBeAb, and HBcAb positive was greater in CHB+HCC group than that in CHB group. Logistic regression analysis indicated that age ≥60 years (OR: 1.835, 95% CI: 1.020-3.302, p=0.043), HBeAb positive (OR: 9.105, 95% CI: 4.796-17.288, p<0.001), antiviral treatment with entecavir (OR: 2.209, 95% CI: 1.106-4.409, p=0.025), and GGT (OR: 1.004, 95% CI: 1.001-1.007, p=0.002) were risk factors for HCC in patients with CHB. Conclusion Advanced age, HBeAb positive, antiviral treatment with entecavir, and GGT were independent risk factors for HCC in HBV patients.
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Affiliation(s)
- Haisong Hou
- Laboratory of Pathogenic Biology, Guangdong Medical University, Zhanjiang, People’s Republic of China
- Department of Blood Transfusion, Meizhou People’s Hospital, Meizhou Academy of Medical Sciences, Meizhou, People’s Republic of China
| | - Liu Liang
- Department of Laboratory Medicine, Meizhou People’s Hospital, Meizhou Academy of Medical Sciences, Meizhou, People’s Republic of China
| | - Lihong Deng
- Department of Hepatology, Meizhou People’s Hospital, Meizhou Academy of Medical Sciences, Meizhou, People’s Republic of China
| | - Wanping Ye
- Department of Gastroenterology, Meizhou People’s Hospital, Meizhou Academy of Medical Sciences, Meizhou, People’s Republic of China
| | - Yuanzhang Wen
- Department of Hepatobiliary Surgery, Meizhou People’s Hospital, Meizhou Academy of Medical Sciences, Meizhou, People’s Republic of China
| | - Jun Liu
- Laboratory of Pathogenic Biology, Guangdong Medical University, Zhanjiang, People’s Republic of China
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2
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Yang S, Liu Y, Feng X, Wang X, Wu M, Gong L, Shu B, Lu Q, Dong J. HBx acts as an oncogene and promotes the invasion and metastasis of hepatocellular carcinoma both in vivo and vitro. Dig Liver Dis 2021; 53:360-366. [PMID: 33153927 DOI: 10.1016/j.dld.2020.10.007] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/18/2020] [Revised: 09/21/2020] [Accepted: 10/05/2020] [Indexed: 12/24/2022]
Abstract
BACKGROUND AND AIMS Hepatitis B virus X (HBx) has been reported to be closely related to hepatitis B virus (HBV)-related hepatocellular carcinoma (HCC). This study aimed to detect the expression pattern of HBx and explore whether HBx protein can promote HCC invasion and metastasis both in vivo and vitro. METHODS HBx expression was detected in HCC tissues via immunochemistry. A recombinant adenovirus vector containing the HBx gene was constructed and transfected into the HCC cell line SMMC-7721. Wound healing, transwell migration, and invasion assays were performed to evaluate migration and invasion potentials. A splenic implant tumor nude mice model was established to confirm its invasion and metastatic abilities in vivo. RESULTS The positive rate of HBx in HCC tissues was 67.89%. HBx overexpression significantly promoted the migration and invasion abilities of SMMC-7721 cells in vitro. The tumor model showed that splenic implant tumor volume and number of liver metastatic tumor nodes were significantly larger and higher in the HBx overexpression group than in the control group. CONCLUSIONS HBx is highly expressed in HCC tissues and promotes HCC invasion and metastasis both in vivo and vitro with oncogene activity, thereby suggesting that HBx can serve as a novel therapeutic target in HCC.
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Affiliation(s)
- Shizhong Yang
- Hepato-Pancreato-Biliary Center, Beijing Tsinghua Changgung Hospital, School of Clinical Medicine, Tsinghua University, Beijing, China
| | - Yanfeng Liu
- Department of Hepato-Biliary Surgery, Qilu Hospital of Shandong University, Jinan, China
| | - Xiaobin Feng
- Hepato-Pancreato-Biliary Center, Beijing Tsinghua Changgung Hospital, School of Clinical Medicine, Tsinghua University, Beijing, China
| | - Xiaojuan Wang
- Hepato-Pancreato-Biliary Center, Beijing Tsinghua Changgung Hospital, School of Clinical Medicine, Tsinghua University, Beijing, China
| | - Meilong Wu
- Hepato-Pancreato-Biliary Center, Beijing Tsinghua Changgung Hospital, School of Clinical Medicine, Tsinghua University, Beijing, China
| | - Lei Gong
- Hepato-Pancreato-Biliary Center, Beijing Tsinghua Changgung Hospital, School of Clinical Medicine, Tsinghua University, Beijing, China
| | - Bin Shu
- Hepato-Pancreato-Biliary Center, Beijing Tsinghua Changgung Hospital, School of Clinical Medicine, Tsinghua University, Beijing, China
| | - Qian Lu
- Hepato-Pancreato-Biliary Center, Beijing Tsinghua Changgung Hospital, School of Clinical Medicine, Tsinghua University, Beijing, China
| | - Jiahong Dong
- Hepato-Pancreato-Biliary Center, Beijing Tsinghua Changgung Hospital, School of Clinical Medicine, Tsinghua University, Beijing, China.
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3
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Vescovo T, Pagni B, Piacentini M, Fimia GM, Antonioli M. Regulation of Autophagy in Cells Infected With Oncogenic Human Viruses and Its Impact on Cancer Development. Front Cell Dev Biol 2020; 8:47. [PMID: 32181249 PMCID: PMC7059124 DOI: 10.3389/fcell.2020.00047] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2019] [Accepted: 01/20/2020] [Indexed: 12/14/2022] Open
Abstract
About 20% of total cancer cases are associated to infections. To date, seven human viruses have been directly linked to cancer development: high-risk human papillomaviruses (hrHPVs), Merkel cell polyomavirus (MCPyV), hepatitis B virus (HBV), hepatitis C virus (HCV), Epstein–Barr virus (EBV), Kaposi’s sarcoma-associated herpesvirus (KSHV), and human T-lymphotropic virus 1 (HTLV-1). These viruses impact on several molecular mechanisms in the host cells, often resulting in chronic inflammation, uncontrolled proliferation, and cell death inhibition, and mechanisms, which favor viral life cycle but may indirectly promote tumorigenesis. Recently, the ability of oncogenic viruses to alter autophagy, a catabolic process activated during the innate immune response to infections, is emerging as a key event for the onset of human cancers. Here, we summarize the current understanding of the molecular mechanisms by which human oncogenic viruses regulate autophagy and how this negative regulation impacts on cancer development. Finally, we highlight novel autophagy-related candidates for the treatment of virus-related cancers.
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Affiliation(s)
- Tiziana Vescovo
- National Institute for Infectious Diseases "Lazzaro Spallanzani" - IRCCS, Rome, Italy
| | - Benedetta Pagni
- National Institute for Infectious Diseases "Lazzaro Spallanzani" - IRCCS, Rome, Italy.,Department of Biology, University of Rome "Tor Vergata," Rome, Italy
| | - Mauro Piacentini
- National Institute for Infectious Diseases "Lazzaro Spallanzani" - IRCCS, Rome, Italy.,Department of Biology, University of Rome "Tor Vergata," Rome, Italy
| | - Gian Maria Fimia
- National Institute for Infectious Diseases "Lazzaro Spallanzani" - IRCCS, Rome, Italy.,Department of Molecular Medicine, University of Rome "Sapienza," Rome, Italy
| | - Manuela Antonioli
- National Institute for Infectious Diseases "Lazzaro Spallanzani" - IRCCS, Rome, Italy
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4
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Park S, Ha YN, Dezhbord M, Lee AR, Park ES, Park YK, Won J, Kim NY, Choo SY, Shin JJ, Ahn CH, Kim KH. Suppression of Hepatocyte Nuclear Factor 4 α by Long-term Infection of Hepatitis B Virus Contributes to Tumor Cell Proliferation. Int J Mol Sci 2020; 21:ijms21030948. [PMID: 32023898 PMCID: PMC7037729 DOI: 10.3390/ijms21030948] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2019] [Revised: 01/24/2020] [Accepted: 01/29/2020] [Indexed: 12/15/2022] Open
Abstract
Hepatitis B virus (HBV) infection is a major factor in the development of various liver diseases such as hepatocellular carcinoma (HCC). Among HBV encoded proteins, HBV X protein (HBx) is known to play a key role in the development of HCC. Hepatocyte nuclear factor 4α (HNF4α) is a nuclear transcription factor which is critical for hepatocyte differentiation. However, the expression level as well as its regulatory mechanism in HBV infection have yet to be clarified. Here, we observed the suppression of HNF4α in cells which stably express HBV whole genome or HBx protein alone, while transient transfection of HBV replicon or HBx plasmid had no effect on the HNF4α level. Importantly, in the stable HBV- or HBx-expressing hepatocytes, the downregulated level of HNF4α was restored by inhibiting the ERK signaling pathway. Our data show that HNF4α was suppressed during long-term HBV infection in cultured HepG2-NTCP cells as well as in a mouse model following hydrodynamic injection of pAAV-HBV or in mice intravenously infected with rAAV-HBV. Importantly, HNF4α downregulation increased cell proliferation, which contributed to the formation and development of tumor in xenograft nude mice. The data presented here provide proof of the effect of HBV infection in manipulating the HNF4α regulatory pathway in HCC development.
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Affiliation(s)
| | | | | | | | | | | | | | | | | | | | | | - Kyun-Hwan Kim
- Correspondence: ; Tel.: +82-2-2030-7833; Fax: +82-2-2049-6192
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5
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Comparison of clinical manifestations and outcomes of noncirrhotic and cirrhotic hepatocellular carcinoma patients with chronic hepatitis B. Eur J Gastroenterol Hepatol 2020; 32:66-73. [PMID: 31268949 DOI: 10.1097/meg.0000000000001478] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/10/2022]
Abstract
AIM The differences of the clinical features and survival outcomes between cirrhotic and noncirrhotic hepatocellular carcinoma (HCC) patients with hepatitis B virus (HBV) infection remain to be determined. We evaluated clinical characteristics and survival outcomes of noncirrhotic HBV-associated HCC patients compared with cirrhotic patients. PATIENTS AND METHODS Between January 2005 and December 2015, 1345 patients were diagnosed to have HCC at our hospital. Of these, 860 HBV-associated HCC patients with (cirrhotic group, n = 519, 60.3%) or without cirrhosis (noncirrhotic group, n = 341, 39.7%) were retrospectively analyzed. Propensity score matching (PSM) was used to adjust for differences between the two groups. RESULTS The noncirrhotic group had lower Child-Turcotte-Pugh (CTP) classes and greater tumor sizes and were less likely to have portal vein thrombosis than the cirrhotic group. Age and sex were not significantly different between the two groups. Cumulative overall survival (OS) rates at 2, 4, 6, and 8 years after treatment were significantly higher in the noncirrhotic group (67.2, 57.1, 43.2, and 38.3 vs. 58.3, 41.3, 33.2, and 27.8%, respectively, P < 0.001). However, no significant intergroup difference in OS rates was observed after PSM (P = 0.680). Significant predictive factors of OS were CTP class, tumor size, tumor number, and curative-intended treatment for the noncirrhotic group, and serum alanine aminotransferase, CTP class, tumor size, tumor number, and curative-intended treatment for the cirrhotic group. CONCLUSION After PSM, cumulative OS rates were similar between HBV-related HCC patients with and without cirrhosis, and they were clearly dependent on CTP class, regardless of the presence of cirrhosis itself both in cirrhotic and noncirrhotic patients.
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6
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DuShane JK, Maginnis MS. Human DNA Virus Exploitation of the MAPK-ERK Cascade. Int J Mol Sci 2019; 20:ijms20143427. [PMID: 31336840 PMCID: PMC6679023 DOI: 10.3390/ijms20143427] [Citation(s) in RCA: 44] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2019] [Revised: 07/09/2019] [Accepted: 07/11/2019] [Indexed: 12/19/2022] Open
Abstract
The extracellular signal-regulated kinases (ERKs) comprise a particular branch of the mitogen-activated protein kinase cascades (MAPK) that transmits extracellular signals into the intracellular environment to trigger cellular growth responses. Similar to other MAPK cascades, the MAPK-ERK pathway signals through three core kinases—Raf, MAPK/ERK kinase (MEK), and ERK—which drive the signaling mechanisms responsible for the induction of cellular responses from extracellular stimuli including differentiation, proliferation, and cellular survival. However, pathogens like DNA viruses alter MAPK-ERK signaling in order to access DNA replication machineries, induce a proliferative state in the cell, or even prevent cell death mechanisms in response to pathogen recognition. Differential utilization of this pathway by multiple DNA viruses highlights the dynamic nature of the MAPK-ERK pathway within the cell and the importance of its function in regulating a wide variety of cellular fates that ultimately influence viral infection and, in some cases, result in tumorigenesis.
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Affiliation(s)
- Jeanne K DuShane
- Department of Molecular and Biomedical Sciences, The University of Maine, Orono, ME 04401, USA
| | - Melissa S Maginnis
- Department of Molecular and Biomedical Sciences, The University of Maine, Orono, ME 04401, USA.
- Graduate School in Biomedical Sciences and Engineering, The University of Maine, Orono, ME 04401, USA.
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7
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Khan M, Imam H, Siddiqui A. Subversion of cellular autophagy during virus infection: Insights from hepatitis B and hepatitis C viruses. LIVER RESEARCH 2018; 2:146-156. [PMID: 31803515 PMCID: PMC6892584 DOI: 10.1016/j.livres.2018.09.002] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Autophagy is a self-eating process, in which the damaged or excessed cell organelles and misfolded protein aggregates are removed from the cellular microenvironment. Autophagy is generally thought of as a pro-survival mechanism which is not only important for balancing energy supply at times of nutrient deprivation but also in the removal of various stress stimuli to ensure homeostasis. In addition to the target materials of "self" origin, autophagy can also eliminate intracellular pathogens and acts as a defense mechanism to curb infections. In addition, autophagy is linked to the host cell's innate immune response. However, viruses have evolved various strategies to manipulate and overtake host cell machinery to establish productive replication and maintain infectious process. In fact, replication of many viruses has been found to be autophagy-dependent and suppression of autophagy can potentially affect the viral replication. Thus, autophagy can either serve as an anti-viral defense mechanism or a pro-viral process that supports viral replication. Hepatitis B virus (HBV) and hepatitis C virus (HCV) are known to co-opt cellular autophagy process as a pro-viral tool. Both viruses also induce mitophagy, which contributes to the establishment of chronic hepatitis. This review focuses on the roles of autophagy and mitophagy in the chronic liver disease pathogenesis associated with HBV and HCV infections.
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8
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Wu MY, Yiang GT, Cheng PW, Chu PY, Li CJ. Molecular Targets in Hepatocarcinogenesis and Implications for Therapy. J Clin Med 2018; 7:213. [PMID: 30104473 PMCID: PMC6112027 DOI: 10.3390/jcm7080213] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2018] [Revised: 08/07/2018] [Accepted: 08/10/2018] [Indexed: 02/07/2023] Open
Abstract
Hepatocarcinogenesis comprises of multiple, complex steps that occur after liver injury and usually involve several pathways, including telomere dysfunction, cell cycle, WNT/β-catenin signaling, oxidative stress and mitochondria dysfunction, autophagy, apoptosis, and AKT/mTOR signaling. Following liver injury, gene mutations, accumulation of oxidative stress, and local inflammation lead to cell proliferation, differentiation, apoptosis, and necrosis. The persistence of this vicious cycle in turn leads to further gene mutation and dysregulation of pro- and anti-inflammatory cytokines, such as interleukin (IL)-1β, IL-6, IL-10, IL-12, IL-13, IL-18, and transforming growth factor (TGF)-β, resulting in immune escape by means of the NF-κB and inflammasome signaling pathways. In this review, we summarize studies focusing on the roles of hepatocarcinogenesis and the immune system in liver cancer. In addition, we furnish an overview of recent basic and clinical studies to provide a strong foundation to develop novel anti-carcinogenesis targets for further treatment interventions.
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Affiliation(s)
- Meng-Yu Wu
- Department of Emergency Medicine, Taipei Tzu Chi Hospital, Buddhist Tzu Chi Medical Foundation, New Taipei City 231, Taiwan.
- Department of Emergency Medicine, School of Medicine, Tzu Chi University, Hualien 970, Taiwan.
| | - Giuo-Teng Yiang
- Department of Emergency Medicine, Taipei Tzu Chi Hospital, Buddhist Tzu Chi Medical Foundation, New Taipei City 231, Taiwan.
- Department of Emergency Medicine, School of Medicine, Tzu Chi University, Hualien 970, Taiwan.
| | - Pei-Wen Cheng
- Yuh-Ing Junior College of Health Care & Management, Kaohsiung 807, Taiwan.
- Department of Medical Education and Research, Kaohsiung Veterans General Hospital, Kaohsiung 813, Taiwan.
| | - Pei-Yi Chu
- School of Medicine, College of Medicine, Fu Jen Catholic University, New Taipei City 231, Taiwan.
- Department of Pathology, Show Chwan Memorial Hospital, Changhua 500, Taiwan.
- National Institute of Cancer Research, National Health Research Institutes, Miaoli 704, Taiwan.
| | - Chia-Jung Li
- Research Assistant Center, Show Chwan Memorial Hospital, Changhua 500, Taiwan.
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9
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Mani SKK, Andrisani O. Hepatitis B Virus-Associated Hepatocellular Carcinoma and Hepatic Cancer Stem Cells. Genes (Basel) 2018; 9:genes9030137. [PMID: 29498629 PMCID: PMC5867858 DOI: 10.3390/genes9030137] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2018] [Revised: 02/23/2018] [Accepted: 02/23/2018] [Indexed: 02/06/2023] Open
Abstract
Chronic Hepatitis B Virus (HBV) infection is linked to hepatocellular carcinoma (HCC) pathogenesis. Despite the availability of a HBV vaccine, current treatments for HCC are inadequate. Globally, 257 million people are chronic HBV carriers, and children born from HBV-infected mothers become chronic carriers, destined to develop liver cancer. Thus, new therapeutic approaches are needed to target essential pathways involved in HCC pathogenesis. Accumulating evidence supports existence of hepatic cancer stem cells (hCSCs), which contribute to chemotherapy resistance and cancer recurrence after treatment or surgery. Understanding how hCSCs form will enable development of therapeutic strategies to prevent their formation. Recent studies have identified an epigenetic mechanism involving the downregulation of the chromatin modifying Polycomb Repressive Complex 2 (PRC2) during HBV infection, which results in re-expression of hCSC marker genes in infected hepatocytes and HBV-associated liver tumors. However, the genesis of hCSCs requires, in addition to the expression of hCSC markers cellular changes, rewiring of metabolism, cell survival, escape from programmed cell death, and immune evasion. How these changes occur in chronically HBV-infected hepatocytes is not yet understood. In this review, we will present the basics about HBV infection and hepatocarcinogenesis. Next, we will discuss studies describing the mutational landscape of liver cancers and how epigenetic mechanisms likely orchestrate cellular reprograming of hepatocytes to enable formation of hCSCs.
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Affiliation(s)
- Saravana Kumar Kailasam Mani
- Department of Basic Medical Sciences and Purdue Center for Cancer Research, Purdue University, West Lafayette, IN 47907, USA.
| | - Ourania Andrisani
- Department of Basic Medical Sciences and Purdue Center for Cancer Research, Purdue University, West Lafayette, IN 47907, USA.
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10
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Reactive Oxygen Species-Mediated c-Jun NH 2-Terminal Kinase Activation Contributes to Hepatitis B Virus X Protein-Induced Autophagy via Regulation of the Beclin-1/Bcl-2 Interaction. J Virol 2017; 91:JVI.00001-17. [PMID: 28515304 DOI: 10.1128/jvi.00001-17] [Citation(s) in RCA: 61] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2017] [Accepted: 05/07/2017] [Indexed: 02/08/2023] Open
Abstract
Autophagy is closely associated with the regulation of hepatitis B virus (HBV) replication. HBV X protein (HBx), a multifunctional regulator in HBV-associated biological processes, has been demonstrated to be crucial for autophagy induction by HBV. However, the molecular mechanisms of autophagy induction by HBx, especially the signaling pathways involved, remain elusive. In the present investigation, we demonstrated that HBx induced autophagosome formation independently of the class I phosphatidylinositol 3-kinase (PI3K)/AKT/mTOR signaling pathway. In contrast, the class III PI3K(VPS34)/beclin-1 pathway was revealed to be critical for HBx-induced autophagosome formation. Further study showed that HBx did not affect the level of VPS34 and beclin-1 expression but inhibited beclin-1/Bcl-2 association, and c-Jun NH2-terminal kinase (JNK) signaling was found to be important for this process. Moreover, it was found that HBx treatment led to the generation of reactive oxygen species (ROS), and inhibition of ROS activity abrogated both JNK activation and autophagosome formation. Of importance, ROS-JNK signaling was also revealed to play an important role in HBV-induced autophagosome formation and subsequent HBV replication. These data may provide deeper insight into the mechanisms of autophagy induction by HBx and help in the design of new therapeutic strategies against HBV infection.IMPORTANCE HBx plays a key role in diverse HBV-associated biological processes, including autophagy induction. However, the molecular mechanisms of autophagy induction by HBx, especially the signaling pathways involved, remain elusive. In the present investigation, we found that HBx induced autophagy independently of the class I PI3K/AKT/mTOR signaling pathway, while the class III PI3K(VPS34)/beclin-1 pathway was revealed to be crucial for this process. Further data showed that ROS-JNK activation by HBx resulted in the release of beclin-1 from its association with Bcl-2 to form a complex with VPS34, thus enhancing autophagosome formation. Of importance, ROS-JNK signaling was also demonstrated to be critical for HBV replication via regulation of autophagy induction. These data help to elucidate the molecular mechanisms of autophagy induction by HBx/HBV and might be useful for designing novel therapeutic approaches to HBV infection.
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11
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Dai XQ, Cai WT, Wu X, Chen Y, Han FM. Protocatechuic acid inhibits hepatitis B virus replication by activating ERK1/2 pathway and down-regulating HNF4α and HNF1α in vitro. Life Sci 2017; 180:68-74. [DOI: 10.1016/j.lfs.2017.05.015] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2017] [Revised: 05/09/2017] [Accepted: 05/11/2017] [Indexed: 01/02/2023]
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12
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Leite FGG, Torres AA, De Oliveira LC, Da Cruz AFP, Soares-Martins JAP, Pereira ACTC, Trindade GS, Abrahão JS, Kroon EG, Ferreira PCP, Bonjardim CA. c-Jun integrates signals from both MEK/ERK and MKK/JNK pathways upon vaccinia virus infection. Arch Virol 2017. [PMID: 28620810 DOI: 10.1007/s00705-017-3446-6] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Usurpation of the host's signalling pathways is a common strategy employed by viruses to promote their successful replication. Here we show that infection with the orthopoxvirus vaccinia virus (VACV) leads to sustained stimulation of c-Jun activity during the entire infective cycle. This stimulation is temporally regulated through MEK/ERK or MKK/JNK pathways, i.e. during the early/mid phase (1 to 6 hpi) and in the late phase (9 to 24 hpi) of the infective cycle, respectively. As a transcriptional regulator, upon infection with VACV, c-Jun is translocated from the cytoplasm to the nucleus, where it binds to the AP-1 DNA sequence found at the promoter region of its target genes. To investigate the role played by c-Jun during VACV replication cycle, we generated cell lines that stably express a c-Jun-dominant negative (DNc-Jun) mutation. Our data revealed that c-Jun is required during early infection to assist with viral DNA replication, as demonstrated by the decreased amount of viral DNA found in the DNc-Jun cells. We also demonstrated that c-Jun regulates the expression of the early growth response gene (egr-1), a gene previously shown to affect VACV replication mediated by MEK/ERK signalling. VACV-induced stimulation of the MKK/JNK/JUN pathway impacts viral dissemination, as we observed a significant reduction in both viral yield, during late stages of infection, and virus plaque size. Collectively, our data suggest that, by modulating the host's signalling pathways through a common target such as c-Jun, VACV temporally regulates its infective cycle in order to successfully replicate and subsequently spread.
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Affiliation(s)
- Flávia G G Leite
- Signal Transduction Group/Orthopoxviruses, Department of Microbiology, Institute of Biological Sciences, Universidade Federal de Minas Gerais, Av. Antônio Carlos, 6627, Campus Pampulha, Belo Horizonte, MG, 31270-901, Brazil.,Laboratório de Vírus, Department of Microbiology, Institute of Biological Sciences, Universidade Federal de Minas Gerais, Av. Antônio Carlos, 6627, Campus Pampulha, Belo Horizonte, MG, 31270-901, Brazil.,Cellular Signalling and Cytoskeletal function Laboratory, The Francis Crick Institute, 1 Midland Road, London, NW1 1AT, UK
| | - Alice A Torres
- Signal Transduction Group/Orthopoxviruses, Department of Microbiology, Institute of Biological Sciences, Universidade Federal de Minas Gerais, Av. Antônio Carlos, 6627, Campus Pampulha, Belo Horizonte, MG, 31270-901, Brazil.,Laboratório de Vírus, Department of Microbiology, Institute of Biological Sciences, Universidade Federal de Minas Gerais, Av. Antônio Carlos, 6627, Campus Pampulha, Belo Horizonte, MG, 31270-901, Brazil.,University of Cambridge, Tennis Court Road, Cambridge, CB2 1QP, UK
| | - Leonardo C De Oliveira
- Signal Transduction Group/Orthopoxviruses, Department of Microbiology, Institute of Biological Sciences, Universidade Federal de Minas Gerais, Av. Antônio Carlos, 6627, Campus Pampulha, Belo Horizonte, MG, 31270-901, Brazil.,Laboratório de Vírus, Department of Microbiology, Institute of Biological Sciences, Universidade Federal de Minas Gerais, Av. Antônio Carlos, 6627, Campus Pampulha, Belo Horizonte, MG, 31270-901, Brazil
| | - André F P Da Cruz
- Signal Transduction Group/Orthopoxviruses, Department of Microbiology, Institute of Biological Sciences, Universidade Federal de Minas Gerais, Av. Antônio Carlos, 6627, Campus Pampulha, Belo Horizonte, MG, 31270-901, Brazil.,Laboratório de Vírus, Department of Microbiology, Institute of Biological Sciences, Universidade Federal de Minas Gerais, Av. Antônio Carlos, 6627, Campus Pampulha, Belo Horizonte, MG, 31270-901, Brazil
| | - Jamária A P Soares-Martins
- Signal Transduction Group/Orthopoxviruses, Department of Microbiology, Institute of Biological Sciences, Universidade Federal de Minas Gerais, Av. Antônio Carlos, 6627, Campus Pampulha, Belo Horizonte, MG, 31270-901, Brazil.,Laboratório de Vírus, Department of Microbiology, Institute of Biological Sciences, Universidade Federal de Minas Gerais, Av. Antônio Carlos, 6627, Campus Pampulha, Belo Horizonte, MG, 31270-901, Brazil.,Department of Math and Science, Waukesha County Technical College, 800 Main Street, Pewaukee, WI, 53072, USA
| | - Anna C T C Pereira
- Signal Transduction Group/Orthopoxviruses, Department of Microbiology, Institute of Biological Sciences, Universidade Federal de Minas Gerais, Av. Antônio Carlos, 6627, Campus Pampulha, Belo Horizonte, MG, 31270-901, Brazil.,Laboratório de Vírus, Department of Microbiology, Institute of Biological Sciences, Universidade Federal de Minas Gerais, Av. Antônio Carlos, 6627, Campus Pampulha, Belo Horizonte, MG, 31270-901, Brazil.,Laboratory of Biochemistry and Biology of Microorganisms and Plants, Universidade Federal do Piauí, Campus de Parnaíba, Av. São Sebastião, 2819, Bairro Reis Velloso, Parnaíba, PI, CEP 64202-020, Brazil
| | - Giliane S Trindade
- Laboratório de Vírus, Department of Microbiology, Institute of Biological Sciences, Universidade Federal de Minas Gerais, Av. Antônio Carlos, 6627, Campus Pampulha, Belo Horizonte, MG, 31270-901, Brazil
| | - Jonatas S Abrahão
- Laboratório de Vírus, Department of Microbiology, Institute of Biological Sciences, Universidade Federal de Minas Gerais, Av. Antônio Carlos, 6627, Campus Pampulha, Belo Horizonte, MG, 31270-901, Brazil
| | - Erna G Kroon
- Laboratório de Vírus, Department of Microbiology, Institute of Biological Sciences, Universidade Federal de Minas Gerais, Av. Antônio Carlos, 6627, Campus Pampulha, Belo Horizonte, MG, 31270-901, Brazil
| | - Paulo C P Ferreira
- Laboratório de Vírus, Department of Microbiology, Institute of Biological Sciences, Universidade Federal de Minas Gerais, Av. Antônio Carlos, 6627, Campus Pampulha, Belo Horizonte, MG, 31270-901, Brazil
| | - Cláudio A Bonjardim
- Signal Transduction Group/Orthopoxviruses, Department of Microbiology, Institute of Biological Sciences, Universidade Federal de Minas Gerais, Av. Antônio Carlos, 6627, Campus Pampulha, Belo Horizonte, MG, 31270-901, Brazil. .,Laboratório de Vírus, Department of Microbiology, Institute of Biological Sciences, Universidade Federal de Minas Gerais, Av. Antônio Carlos, 6627, Campus Pampulha, Belo Horizonte, MG, 31270-901, Brazil.
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13
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Quetier I, Brezillon N, Revaud J, Ahodantin J, DaSilva L, Soussan P, Kremsdorf D. C-terminal-truncated hepatitis B virus X protein enhances the development of diethylnitrosamine-induced hepatocellular carcinogenesis. J Gen Virol 2014; 96:614-625. [PMID: 25519169 DOI: 10.1099/vir.0.070680-0] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Hepatitis B virus X protein (HBx) is involved in the development of hepatocellular carcinoma (HCC). The HBx sequence is a preferential site of integration into the human genome, leading to the formation of C-terminal-truncated HBx proteins (Ct-HBx). We previously reported that Ct-HBx proteins were able to potentiate cell transformation in vitro. Our present goal was to compare the ability of Ct-HBx and full-length HBx (FL-HBx) proteins to develop or enhance HCC in transgenic mice. In the absence of treatment, neither Ct-HBx- nor FL-HBx-transgenic mice developed HCC. In young mice treated with diethylnitrosamine (DEN) at 8 months of age, a significantly higher incidence and number of liver lesions were observed in Ct-HBx mice than in FL-HBx and control mice. The earlier development of tumours in Ct-HBx-transgenic mice was associated with increased liver inflammation. At 10 months, macroscopic and microscopic analyses showed that, statistically, FL-HBx mice developed more liver lesions with a larger surface area than control mice. Furthermore, during DEN-induced initiation of HCC, Ct-HBx- and FL-HBx-transgenic mice showed higher expression of IL-6, TNF-α and IL-1β transcripts, activation of STAT3, ERK and JNK proteins and an increase in cell apoptosis. In conclusion, in DEN-treated transgenic mice, the expression of Ct-HBx protein causes a more rapid onset of HCC than does FL-HBx protein. HBV genome integration leading to the expression of a truncated form of HBx protein may therefore facilitate HCC development in chronically infected patients.
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Affiliation(s)
- Ivan Quetier
- Institut Pasteur, Département de Virologie, Paris, France
- Université Paris Descartes, Sorbonne Paris-Cité, Faculté de Médecine Necker, Paris, France
- Inserm, U845, Team 'Pathogenèse des hépatites virales B et immunothérapie', Paris, France
| | - Nicolas Brezillon
- Université Paris Descartes, Sorbonne Paris-Cité, Faculté de Médecine Necker, Paris, France
- Inserm, U845, Team 'Pathogenèse des hépatites virales B et immunothérapie', Paris, France
- Institut Pasteur, Département de Virologie, Paris, France
| | - Julien Revaud
- Institut Pasteur, Département de Virologie, Paris, France
- Université Paris Descartes, Sorbonne Paris-Cité, Faculté de Médecine Necker, Paris, France
- Inserm, U845, Team 'Pathogenèse des hépatites virales B et immunothérapie', Paris, France
| | - James Ahodantin
- Institut Pasteur, Département de Virologie, Paris, France
- Université Paris Descartes, Sorbonne Paris-Cité, Faculté de Médecine Necker, Paris, France
- Inserm, U845, Team 'Pathogenèse des hépatites virales B et immunothérapie', Paris, France
| | - Lucie DaSilva
- Institut Pasteur, Département de Virologie, Paris, France
- Université Paris Descartes, Sorbonne Paris-Cité, Faculté de Médecine Necker, Paris, France
- Inserm, U845, Team 'Pathogenèse des hépatites virales B et immunothérapie', Paris, France
| | - Patrick Soussan
- Université Paris Descartes, Sorbonne Paris-Cité, Faculté de Médecine Necker, Paris, France
- Institut Pasteur, Département de Virologie, Paris, France
- Service de Virologie, Hôpital Tenon, Paris, France
- Université Pierre et Marie Curie, Paris, France
- Inserm, U845, Team 'Pathogenèse des hépatites virales B et immunothérapie', Paris, France
| | - Dina Kremsdorf
- Institut Pasteur, Département de Virologie, Paris, France
- Université Paris Descartes, Sorbonne Paris-Cité, Faculté de Médecine Necker, Paris, France
- Inserm, U845, Team 'Pathogenèse des hépatites virales B et immunothérapie', Paris, France
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14
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Chang KC, Chang Y, Wang LHC, Tsai HW, Huang W, Su IJ. Pathogenesis of virus-associated human cancers: Epstein–Barr virus and hepatitis B virus as two examples. J Formos Med Assoc 2014; 113:581-90. [PMID: 24095032 DOI: 10.1016/j.jfma.2013.09.001] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2013] [Revised: 08/02/2013] [Accepted: 09/02/2013] [Indexed: 12/12/2022] Open
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15
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Mass spectrometric determination of disulfide bonds in the biologically active recombinant HBx protein of hepatitis B virus. Biochemistry 2014; 53:4685-95. [PMID: 24971648 DOI: 10.1021/bi500140t] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Many proteins rely on disulfide bonds formed between pairs of cysteines for the stability of their folded state and to keep regulatory control over their functions. The hepatitis B virus-encoded HBx oncoprotein is known to perform an overwhelming array of functions in the cell and has been implicated in the development of hepatocellular carcinoma. However, its structure has not been elucidated. HBx carries nine conserved cysteine residues that have proven to be crucial for its various functions. However, the status of disulfide bonds between the cysteine residues reported in previous studies remains discrepant because of the use of refolded recombinant HBx that may contain non-native disulfides. Now we have determined the disulfide linkages in soluble and biologically active recombinant maltose binding protein-HBx fusion protein using matrix-assisted laser desorption ionization time-of-flight mass spectrometry. We report four disulfide linkages in HBx protein, viz., between Cys(7) and Cys(69), Cys(61) and Cys(115), Cys(78) and Cys(137), and Cys(17) and Cys(143), based on the differential mobility of corresponding disulfide-linked peptide ions under reducing and nonreducing conditions. Cys(148) was observed to be free. Site-directed mutagenesis of Cys(143) and Cys(148) with serine and functional analyses of these mutants affirmed the importance of these residues in the ability of HBx to potentiate Cdk2/cyclin E kinase activity and transcriptionally activate promoter reporter gene activity. Thus, this study identifies native disulfide linkages in the structure of a biologically active viral oncoprotein.
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16
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Mansourian PG, Yoneda M, Krishna Rao M, Martinez FJ, Thomas E, Schiff ER. Effects of statins on the risk of hepatocellular carcinoma. Gastroenterol Hepatol (N Y) 2014; 10:417-426. [PMID: 25904829 PMCID: PMC4302489] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Hepatocellular carcinoma (HCC) is one of the leading causes of cancer morbidity and mortality worldwide and is one of the few cancers that is increasing in incidence. This cancer often arises in the setting of hepatic cirrhosis; however, it can also occur in patients with chronic hepatitis B virus infection without cirrhosis. Statins have been used for many years for the prevention and treatment of cardiovascular disease. Based on recent meta-analy-ses, these lipid-lowering agents are now being investigated for a class effect observed in the prevention of carcinogenesis. There are robust data suggesting that statins can alter biochemical pathways involved in tumorigenesis and cell survival and, thus, have a protective effect by reducing the risk of development of several types of cancer. In recent years, several studies have demonstrated that statins also can specifically decrease the risk of HCC development. Because statins are underutilized in patients with preexisting liver disease, understanding the role of statins in the prevention of HCC is important, and changes in practice guidelines supporting the use of statins as chemoprotective agents may be warranted.
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Affiliation(s)
- Pejman G Mansourian
- Dr Mansourian, Dr Yoneda, and Mr Rao are clinical research fellows, Dr Martinez is a gastroenterology fellow, Dr Thomas is an assistant professor, and Dr Schiff is a professor and director of the Schiff Center for Liver Diseases at the University of Miami Miller School of Medicine in Miami, Florida
| | - Masato Yoneda
- Dr Mansourian, Dr Yoneda, and Mr Rao are clinical research fellows, Dr Martinez is a gastroenterology fellow, Dr Thomas is an assistant professor, and Dr Schiff is a professor and director of the Schiff Center for Liver Diseases at the University of Miami Miller School of Medicine in Miami, Florida
| | - M Krishna Rao
- Dr Mansourian, Dr Yoneda, and Mr Rao are clinical research fellows, Dr Martinez is a gastroenterology fellow, Dr Thomas is an assistant professor, and Dr Schiff is a professor and director of the Schiff Center for Liver Diseases at the University of Miami Miller School of Medicine in Miami, Florida
| | - Fernando J Martinez
- Dr Mansourian, Dr Yoneda, and Mr Rao are clinical research fellows, Dr Martinez is a gastroenterology fellow, Dr Thomas is an assistant professor, and Dr Schiff is a professor and director of the Schiff Center for Liver Diseases at the University of Miami Miller School of Medicine in Miami, Florida
| | - Emmanuel Thomas
- Dr Mansourian, Dr Yoneda, and Mr Rao are clinical research fellows, Dr Martinez is a gastroenterology fellow, Dr Thomas is an assistant professor, and Dr Schiff is a professor and director of the Schiff Center for Liver Diseases at the University of Miami Miller School of Medicine in Miami, Florida
| | - Eugene R Schiff
- Dr Mansourian, Dr Yoneda, and Mr Rao are clinical research fellows, Dr Martinez is a gastroenterology fellow, Dr Thomas is an assistant professor, and Dr Schiff is a professor and director of the Schiff Center for Liver Diseases at the University of Miami Miller School of Medicine in Miami, Florida
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17
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Chang C, Lee SO, Yeh S, Chang TM. Androgen receptor (AR) differential roles in hormone-related tumors including prostate, bladder, kidney, lung, breast and liver. Oncogene 2013; 33:3225-34. [PMID: 23873027 DOI: 10.1038/onc.2013.274] [Citation(s) in RCA: 171] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2013] [Revised: 05/09/2013] [Accepted: 05/13/2013] [Indexed: 02/07/2023]
Abstract
The androgen receptor (AR) is expressed in many cell types and the androgen/AR signaling has been found to have important roles in modulating tumorigenesis and metastasis in several cancers including prostate, bladder, kidney, lung, breast and liver. However, whether AR has differential roles in the individual cells within these tumors that contain a variety of cell types remains unclear. Generation of AR knockout (ARKO) mouse models with deletion of AR in selective cells within tumors indeed have uncovered many unique AR roles in the individual cell types during cancer development and progression. This review will discuss the results obtained from various ARKO mice and different human cell lines with special attention to the cell type- and tissue-specific ARKO models. The understanding of various results showing the AR indeed has distinct and contrasting roles in each cell type within many hormone-related tumors (as stimulator in bladder, kidney and lung metastases vs as suppressor in prostate and liver metastases) may eventually help us to develop better therapeutic approaches by targeting the AR or its downstream signaling in individual cell types to better battle these hormone-related tumors in different stages.
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Affiliation(s)
- C Chang
- 1] George Whipple Lab for Cancer Research, Departments of Pathology, Urology, Radiation Oncology, and the Wilmot Cancer Center, University of Rochester Medical Center, Rochester, NY, USA [2] Sex Hormone Research Center, China Medical University/Hospital, Taichung, Taiwan
| | - S O Lee
- George Whipple Lab for Cancer Research, Departments of Pathology, Urology, Radiation Oncology, and the Wilmot Cancer Center, University of Rochester Medical Center, Rochester, NY, USA
| | - S Yeh
- George Whipple Lab for Cancer Research, Departments of Pathology, Urology, Radiation Oncology, and the Wilmot Cancer Center, University of Rochester Medical Center, Rochester, NY, USA
| | - T M Chang
- George Whipple Lab for Cancer Research, Departments of Pathology, Urology, Radiation Oncology, and the Wilmot Cancer Center, University of Rochester Medical Center, Rochester, NY, USA
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18
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Egr-1 enhances drug resistance of breast cancer by modulating MDR1 expression in a GGPPS-independent manner. Biomed Pharmacother 2013; 67:197-202. [DOI: 10.1016/j.biopha.2013.01.001] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2012] [Accepted: 01/07/2013] [Indexed: 11/18/2022] Open
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19
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Chen HF, Mai JR, Wan JX, Gao YF, Lin LN, Wang SZ, Chen YX, Zhang CZ, Zhang YJ, Xia B, Liao K, Lin YC, Lin ZN. Role of a novel functional variant in the PPP2R1A promoter on the regulation of PP2A-Aalpha and the risk of hepatocellular carcinoma. PLoS One 2013; 8:e59574. [PMID: 23555712 PMCID: PMC3612049 DOI: 10.1371/journal.pone.0059574] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2012] [Accepted: 02/15/2013] [Indexed: 02/06/2023] Open
Abstract
Previously, we identified the genetic variant −241 (−/G) (rs11453459) in the PP2A-Aα gene (PPP2R1A) promoter and demonstrated that this variant influences the DNA-binding affinity of nuclear factor-kappa B (NF-κB). In this study, we further confirmed that the transcriptional activity of PPP2R1A may be regulated by NF-κB through the functional genetic variant −241 (−/G). Moreover, we also demonstrated that the methylation status of CpG islands in the promoter of PPP2R1A influences the activity of this gene promoter. Few studies have examined the role of this −241 (−/G) variant in genetic or epigenetic regulation in hepatocellular carcinoma (HCC). To investigate whether this functional variant in the PPP2R1A promoter is associated with the risk of HCC and confirm the function of the −241 (−/G) variant in the HCC population, we conducted a case-control study involving 251 HCC cases and 252 cancer-free controls from a Han population in southern China. Compared with the −241 (−−) homozygote, the heterozygous −241 (−G) genotype (adjusted OR = 0.32, 95% confidence interval (CI) = 0.17–0.58, P<0.001) and the −241 (−G)/(GG) genotypes (adjusted OR = 0.38, 95% CI = 0.22–0.67, P = 0.001) were both significantly associated with a reduced risk of HCC. Stratification analysis indicated that the protective role of −241 (−G) was more pronounced in individuals who were ≤ 40 years of age, female and HBV-negative. Our data suggest that the transcriptional activity of PPP2R1A is regulated by NF-κB through the −241 (−/G) variant and by the methylation of the promoter region. Moreover, the functional −241 (−/G) variant in the PPP2R1A promoter contributes to the decreased risk of HCC. These findings contribute novel information regarding the gene transcription of PPP2R1A regulated by the polymorphism and methylation in the promoter region through genetic and epigenetic mechanisms in hepatocarcinogenesis.
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Affiliation(s)
- Hui-Feng Chen
- Guangdong Provincial Key Laboratory of Food, Nutrition and Health, School of Public Health, Sun Yat-sen University, Guangzhou, PR China
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20
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Singh S, Singh PP, Singh AG, Murad MH, Sanchez W. Statins are associated with a reduced risk of hepatocellular cancer: a systematic review and meta-analysis. Gastroenterology 2013; 144:323-332. [PMID: 23063971 DOI: 10.1053/j.gastro.2012.10.005] [Citation(s) in RCA: 351] [Impact Index Per Article: 29.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/05/2012] [Revised: 10/03/2012] [Accepted: 10/05/2012] [Indexed: 12/15/2022]
Abstract
BACKGROUND & AIMS Hepatocellular carcinoma (HCC) is a leading cause of cancer-related mortality worldwide. Several studies have shown that statins could have chemopreventive effects on HCC. We performed a systematic review and meta-analysis of studies that evaluated the effects of statins on the risk of HCC. METHODS We conducted a systematic search of MEDLINE, Embase, and Web of Science through May 2012 and manually reviewed the literature. Studies were included if they evaluated and clearly defined exposure to statins, reported the incidence of HCC, and reported relative risks or odds ratios (ORs) or provided data for their estimation. Ten studies reporting 4298 cases of HCC in 1,459,417 patients were analyzed. Summary OR estimates with 95% confidence intervals (CIs) were calculated using the random effects model. Statistical heterogeneity was assessed with the Cochran's Q statistic and I(2) statistic. RESULTS Statin users were less likely to develop HCC than statin nonusers (adjusted OR, 0.63; 95% CI, 0.52-0.76), although the results were heterogeneous (P = .01, I(2) = 59%). This heterogeneity could be accounted for by study location (Asian population [n = 4]: adjusted OR, 0.52; 95% CI, 0.42-0.64; Western population [n = 6]: adjusted OR, 0.67; 95% CI, 0.53-0.85) and design (observational studies [n = 7]: adjusted OR, 0.60; 95% CI, 0.49-0.73; clinical trials [n = 3]: adjusted OR, 0.95; 95% CI, 0.62-1.45). CONCLUSIONS Based on meta-analysis, statin use is associated with a reduced risk of HCC, most strongly in Asian but also in Western populations. Randomized clinical trials in populations at high risk for HCC (especially in Asian populations with hepatitis B) are warranted.
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Affiliation(s)
- Siddharth Singh
- Division of Gastroenterology and Hepatology, Mayo Clinic, Rochester, Minnesota
| | - Preet Paul Singh
- Department of Medical Oncology, Mayo Clinic, Rochester, Minnesota
| | - Abha Goyal Singh
- Department of Internal Medicine, Mayo Clinic, Rochester, Minnesota
| | - Mohammad Hassan Murad
- Division of Preventive, Occupational and Aerospace Medicine, Mayo Clinic, Rochester, Minnesota
| | - William Sanchez
- Division of Gastroenterology and Hepatology, Mayo Clinic, Rochester, Minnesota.
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21
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Wang A, Al-Kuhlani M, Johnston SC, Ojcius DM, Chou J, Dean D. Transcription factor complex AP-1 mediates inflammation initiated by Chlamydia pneumoniae infection. Cell Microbiol 2012; 15:779-94. [PMID: 23163821 DOI: 10.1111/cmi.12071] [Citation(s) in RCA: 67] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2012] [Revised: 10/15/2012] [Accepted: 11/10/2012] [Indexed: 01/17/2023]
Abstract
Chlamydia pneumoniae is responsible for a high prevalence of respiratory infections worldwide and has been implicated in atherosclerosis. Inflammation is regulated by transcription factor (TF) networks. Yet, the core TF network triggered by chlamydiae remains largely unknown. Primary human coronary artery endothelial cells were mock-infected or infected with C. pneumoniae to generate human transcriptome data throughout the chlamydial developmental cycle. Using systems network analysis, the predominant TF network involved receptor, binding and adhesion and immune response complexes. Cells transfected with interfering RNA against activator protein-1 (AP-1) members FOS, FOSB, JUN and JUNB had significantly decreased expression and protein levels of inflammatory mediators interleukin (IL)6, IL8, CD38 and tumour necrosis factor compared with controls. These mediators have been shown to be associated with C. pneumoniae disease. Expression of AP-1 components was regulated by MAPK3K8, a MAPK pathway component. Additionally, knock-down of JUN and FOS showed significantly decreased expression of Toll-like receptor (TLR)3 during infection, implicating JUN and FOS in TLR3 regulation. TLR3 stimulation led to elevated IL8. These findings suggest that C. pneumoniae initiates signalling via TLR3 and MAPK that activate AP-1, a known immune activator in other bacteria not previously shown for chlamydiae, triggering inflammation linked to C. pneumoniae disease.
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Affiliation(s)
- Anyou Wang
- Center for Immunobiology and Vaccine Development, Children's Hospital Oakland Research Institute, Oakland, CA 94609, USA
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22
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GUO PENGTAO, YANG DONG, SUN ZHE, XU HUIMIAN. Hepatitis B virus X protein plays an important role in gastric ulcers. Oncol Rep 2012; 28:1653-8. [DOI: 10.3892/or.2012.2011] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2012] [Accepted: 07/09/2012] [Indexed: 11/06/2022] Open
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23
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Inhibition of the interaction between NS3 protease and HCV IRES with a small peptide: a novel therapeutic strategy. Mol Ther 2012; 21:57-67. [PMID: 22910295 DOI: 10.1038/mt.2012.151] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Abstract
Recently, we have demonstrated that the protease domain of NS3 alone can bind specifically to hepatitis C virus (HCV) internal ribosome entry site (IRES) near the initiator AUG, dislodges human La protein and inhibits translation in favor of viral RNA replication. Here, by using a computational approach, the contact points of the protease on the HCV IRES were putatively mapped. A 30-mer NS3 peptide was designed from the predicted RNA-binding region that retained RNA-binding ability and also inhibited IRES-mediated translation. This peptide was truncated to 15 mer and this also demonstrated ability to inhibit HCV RNA-directed translation as well as replication. More importantly, its activity was tested in an in vivo mouse model by encapsulating the peptide in Sendai virus virosomes followed by intravenous delivery. The study demonstrates for the first time that the HCV NS3-IRES RNA interaction can be selectively inhibited using a small peptide and reports a strategy to deliver the peptide into the liver.
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24
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Yuan K, Lian Z, Sun B, Clayton MM, Ng IOL, Feitelson MA. Role of miR-148a in hepatitis B associated hepatocellular carcinoma. PLoS One 2012; 7:e35331. [PMID: 22496917 PMCID: PMC3322146 DOI: 10.1371/journal.pone.0035331] [Citation(s) in RCA: 78] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2011] [Accepted: 03/13/2012] [Indexed: 12/26/2022] Open
Abstract
Hepatitis B virus encoded X antigen (HBx) is a trans-regulatory protein that alters the activity of selected transcription factors and cytoplasmic signal transduction pathways. HBx transcriptionally up-regulates the expression of a unique gene, URG11, which in turn transcriptionally up-regulates β-catenin, thereby contributing importantly to hepatocarcinogenesis. HBx and URG11 also alter the expression of multiple microRNAs, and by miRNA array analysis, both were shown to promote the expression of miR-148a. Elevated miR-148a was also seen in HBx positive liver samples from infected patients. To study the function of miR-148a, anti-148a was introduced into HepG2 and Hep3B cells stably expressing HBx or stably over-expressing URG11. Anti-miR-148a suppressed cell proliferation, cell cycle progression, cell migration, anchorage independent growth in soft agar and subcutaneous tumor formation in SCID mice. Introduction of anti-miR-148a increased PTEN protein and mRNA expression, suggesting that PTEN was targeted by miR-148a. Anti-miR-148a failed to suppress PTEN expression when co-transfected with reporter gene mutants in the 3′UTR of PTEN mRNA. Introduction of anti-miR-148a also resulted in depressed Akt signaling by HBx and URG11, resulting in decreased expression of β-catenin. Thus, miR-148a may play a central role in HBx/URG11 mediated HCC, and may be an early diagnostic marker and/or therapeutic target associated with this tumor type.
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Affiliation(s)
- Ke Yuan
- Department of Biology, College of Science and Technology, Temple University, Philadelphia, Pennsylvania, United States of America
| | - Zhaorui Lian
- Department of Biology, College of Science and Technology, Temple University, Philadelphia, Pennsylvania, United States of America
| | - Bill Sun
- Department of Biology, College of Science and Technology, Temple University, Philadelphia, Pennsylvania, United States of America
| | - Marcia M. Clayton
- Department of Biology, College of Science and Technology, Temple University, Philadelphia, Pennsylvania, United States of America
| | - Irene O. L. Ng
- Department of Pathology, University of Hong Kong, Queen Mary Hospital, Pokfulam, Hong Kong
| | - Mark A. Feitelson
- Department of Biology, College of Science and Technology, Temple University, Philadelphia, Pennsylvania, United States of America
- Center for Biotechnology, Sbarro Health Research Organization, College of Science and Technology, Temple University, Philadelphia, Pennsylvania, United States of America
- * E-mail:
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25
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Abstract
As one of the principal causes of liver diseases, such as chronic hepatitis B, hepatic cirrhosis and hepatocellular carcinoma (HCC), hepatitis B virus (HBV) infection has been a major health problem worldwide. It is estimated that more than 500 million individuals have been infected with HBV worldwide and 1 million die of HBV infection-associated diseases annually. HBV X protein (HBx) is a multifunctional protein that can modulate various cellular processes and plays a crucial role in the pathogenesis of HCC. In recent years, the role of HBx in HBV replication has been more or less confirmed. In addition, more and more natural HBx truncated mutants and their roles in HBV replication have been found. This review aims to elucidate the roles of HBx and truncated HBx in HBV replication.
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26
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Fatima G, Mathan G, Kumar V. The HBx protein of hepatitis B virus regulates the expression, intracellular distribution and functions of ribosomal protein S27a. J Gen Virol 2011; 93:706-715. [PMID: 22158882 DOI: 10.1099/vir.0.035691-0] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
The pleiotropic HBx protein of hepatitis B virus is linked functionally to the development of hepatocellular carcinoma (HCC) via effectors and signalling pathways of the host. To identify such effectors in a macrocarcinogenic environment, a PCR-based cDNA subtraction analysis was carried out in the X15-myc oncomouse model of HCC. Altogether, 19 categories of genes, mainly involved in protein biosynthesis and the electron-transport chain, were found to be upregulated in the liver of these mice. Ribosomal protein S27a (RPS27a), which is a natural fusion protein of N-terminal ubiquitin and C-terminal extension protein (CEP), topped the list of expressed genes, with >20-fold higher expression compared with its normal level. Sustained and elevated expression of RPS27a in the mouse liver and its moderate expression in cell culture in the presence of HBx suggested an indirect role of RPS27a in hepatocarcinogenesis. Nevertheless, a remarkable change in the intracellular distribution of ubiquitin from cytoplasm to late-endosomal lysosomes, and of CEP from nucleoli to the perinucleolar region/nuclear foci, was observed in the presence of HBx. RPS27a accelerated the progression of the cell cycle and cooperated with HBx in this process. Further, the knockdown of RPS27a expression by RNA interference in an HBx microenvironment led to retarded cell-cycle progression and reduced cell size. Thus, these results suggest strongly that RPS27a could be an effector of HBx-mediated hepatocarcinogenesis.
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Affiliation(s)
- Grace Fatima
- Virology Group, International Centre for Genetic Engineering and Biotechnology (ICGEB), Aruna Asaf Ali Marg, New Delhi 110067, India
| | - Ganeshan Mathan
- Virology Group, International Centre for Genetic Engineering and Biotechnology (ICGEB), Aruna Asaf Ali Marg, New Delhi 110067, India
| | - Vijay Kumar
- Virology Group, International Centre for Genetic Engineering and Biotechnology (ICGEB), Aruna Asaf Ali Marg, New Delhi 110067, India
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Abstract
Agents commonly used in cancer chemotherapy rely on the induction of cell death via apoptosis, mitotic catastrophe, premature senescence and autophagy. Chemoresistance is the major factor limiting long-term treatment success in patients with hepatocellular carcinoma (HCC). Recent studies have revealed that the hepatitis B virus X protein (HBx) exerts anti-apoptotic effects, resulting in an increased drug resistance in HCC cells. In this study, we showed that etoposide treatment activated caspase-8 and caspase-3, leading to cleavages of p53, Bid and PARP, which subsequently induced apoptosis. Furthermore, p53 and Bid were accumulated in cytoplasm following etoposide treatment. However, HBx significantly attenuated etoposide-induced cell death. In HBx-expressing cells, despite the translocation of p53 and Bid to cytoplasm, the activation of caspases was inhibited. Furthermore, the phosphorylation of extracellular-signal-regulated kinase (ERK) was markedly increased in HBx-expressing cells. Moreover, the pretreatment with trichostatin A (TSA, a histone deacetylase inhibitor) or TSA in combination with etoposide significantly sensitized HCC cells to apoptosis by inhibiting ERK phosphorylation, reactivating caspases and PARP, and inducing translocation of p53 and Bid to cytoplasm. Collectively, HBx reduces the sensitivity of HCC cells to chemotherapy. TSA in combination with etoposide can significantly overcome the increased resistance of HBx-expressing HCC cells to chemotherapy.
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Kong GY, Zhang JP, Zhang S, Shan CL, Ye LH, Zhang XD. Hepatitis B virus X protein promotes hepatoma cell proliferation via upregulation of MEKK2. Acta Pharmacol Sin 2011; 32:1173-80. [PMID: 21804577 DOI: 10.1038/aps.2011.52] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
AIM To investigate the mechanism underlying the increase of hepatoma cell proliferation by hepatitis B virus X protein (HBx). METHODS HepG2, H7402 and HepG2.2.15 cells, which constitutively replicated hepatitis B virus were used. The effects of HBx on hepatoma cell proliferation were examined using 5-ethynyl-2-deoxyuridine (EdU) incorporation assay and MTT assay. The expression level of MEKK2 was measured using RT-PCR, Western blot and luciferase reporter gene assay. The activity of activator protein 1 (AP-1) was detected using luciferase reporter gene assay. The phosphorylation levels of JNK and c-Jun were measured using Western blot. The expression levels of HBx and MEKK2 in 11 clinical hepatocellular carcinoma (HCC) tissues were measured using real time PCR and Western blot. In addition, the expression of MEKK2 in 95 clinical HCC tissues was examined using immunohistochemistry. RESULTS HBx significantly enhanced HepG2-X cell proliferation. In HepG2-X, H7402-X and HepG2.2.15 cells, the expression level of MEKK2 was remarkably increased. In HepG2.2.15 cells, HBx was found to activate JNK and AP-1, which were the downstream effectors of MEKK2 in HepG2-X and HepG2.2.15 cells. In 11 clinical HCC tissues, both HBx and MEKK2 expression levels were remarkably increased, as compared to those in the corresponding peritumor tissues. In 95 clinical HCC tissues, the rate of detection of MEKK2 was 85.3%. CONCLUSION HBx promotes hepatoma cell proliferation via upregulating MEKK2, which may be involved in hepatocarcinogenesis.
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Shin HJ, Park YH, Kim SU, Moon HB, Park DS, Han YH, Lee CH, Lee DS, Song IS, Lee DH, Kim M, Kim NS, Kim DG, Kim JM, Kim SK, Kim YN, Kim SS, Choi CS, Kim YB, Yu DY. Hepatitis B virus X protein regulates hepatic glucose homeostasis via activation of inducible nitric oxide synthase. J Biol Chem 2011; 286:29872-81. [PMID: 21690090 PMCID: PMC3191028 DOI: 10.1074/jbc.m111.259978] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2011] [Revised: 06/13/2011] [Indexed: 12/25/2022] Open
Abstract
Dysregulation of liver functions leads to insulin resistance causing type 2 diabetes mellitus and is often found in chronic liver diseases. However, the mechanisms of hepatic dysfunction leading to hepatic metabolic disorder are still poorly understood in chronic liver diseases. The current work investigated the role of hepatitis B virus X protein (HBx) in regulating glucose metabolism. We studied HBx-overexpressing (HBxTg) mice and HBxTg mice lacking inducible nitric oxide synthase (iNOS). Here we show that gene expressions of the key gluconeogenic enzymes were significantly increased in HepG2 cells expressing HBx (HepG2-HBx) and in non-tumor liver tissues of hepatitis B virus patients with high levels of HBx expression. In the liver of HBxTg mice, the expressions of gluconeogenic genes were also elevated, leading to hyperglycemia by increasing hepatic glucose production. However, this effect was insufficient to cause systemic insulin resistance. Importantly, the actions of HBx on hepatic glucose metabolism are thought to be mediated via iNOS signaling, as evidenced by the fact that deficiency of iNOS restored HBx-induced hyperglycemia by suppressing the gene expression of gluconeogenic enzymes. Treatment of HepG2-HBx cells with nitric oxide (NO) caused a significant increase in the expression of gluconeogenic genes, but JNK1 inhibition was completely normalized. Furthermore, hyperactivation of JNK1 in the liver of HBxTg mice was also suppressed in the absence of iNOS, indicating the critical role for JNK in the mutual regulation of HBx- and iNOS-mediated glucose metabolism. These findings establish a novel mechanism of HBx-driven hepatic metabolic disorder that is modulated by iNOS-mediated activation of JNK.
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Affiliation(s)
- Hye-Jun Shin
- From the Disease Model Research Laboratory, Aging Research Center and World Class Institute, Korea Research Institute of Bioscience and Biotechnology, Daejeon 305-806, Republic of Korea
- the College of Veterinary Medicine, Chungnam National University, Daejeon 305-764, Republic of Korea
| | - Young-Ho Park
- From the Disease Model Research Laboratory, Aging Research Center and World Class Institute, Korea Research Institute of Bioscience and Biotechnology, Daejeon 305-806, Republic of Korea
- the Department of Functional Genomics, University of Science and Technology, Daejeon 305-333, Republic of Korea
| | - Sun-Uk Kim
- From the Disease Model Research Laboratory, Aging Research Center and World Class Institute, Korea Research Institute of Bioscience and Biotechnology, Daejeon 305-806, Republic of Korea
| | - Hyung-Bae Moon
- the Department of Pathology and Institute of Medical Science, Wonkwang University College of Medicine, Iksan 570-749, Republic of Korea
| | - Do Sim Park
- the Department of Pathology and Institute of Medical Science, Wonkwang University College of Medicine, Iksan 570-749, Republic of Korea
| | - Ying-Hao Han
- From the Disease Model Research Laboratory, Aging Research Center and World Class Institute, Korea Research Institute of Bioscience and Biotechnology, Daejeon 305-806, Republic of Korea
| | - Chul-Ho Lee
- From the Disease Model Research Laboratory, Aging Research Center and World Class Institute, Korea Research Institute of Bioscience and Biotechnology, Daejeon 305-806, Republic of Korea
| | - Dong-Seok Lee
- From the Disease Model Research Laboratory, Aging Research Center and World Class Institute, Korea Research Institute of Bioscience and Biotechnology, Daejeon 305-806, Republic of Korea
- the College of Natural Sciences, Kyungpook National University, Daegu 702-701, Republic of Korea
| | - In-Sung Song
- the Genome Research Center, Korea Research Institute of Bioscience and Biotechnology, Daejeon 305-806, Republic of Korea
| | - Dae Ho Lee
- the Division of Endocrinology, Diabetes and Metabolism, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts 02215
| | - Minhye Kim
- the Division of Endocrinology, Diabetes and Metabolism, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts 02215
| | - Nam-Soon Kim
- the Genome Research Center, Korea Research Institute of Bioscience and Biotechnology, Daejeon 305-806, Republic of Korea
| | - Dae-Ghon Kim
- the Department of Internal Medicine, Chonbuk National University Medical School and Hospital, Jeonju 561-756, Republic of Korea
| | - Jin-Man Kim
- the College of Medicine, Chungnam National University, Daejeon 305-764, Republic of Korea, and
| | - Sang-Keun Kim
- the College of Veterinary Medicine, Chungnam National University, Daejeon 305-764, Republic of Korea
| | - Yo Na Kim
- the Lee Gil Ya Cancer and Diabetes Institute and
| | - Su Sung Kim
- the Lee Gil Ya Cancer and Diabetes Institute and
| | - Cheol Soo Choi
- the Lee Gil Ya Cancer and Diabetes Institute and
- Division of Endocrinology Gil Medical Center, Gachon University of Medicine and Science, Incheon 406-840, Republic of Korea
| | - Young-Bum Kim
- the Division of Endocrinology, Diabetes and Metabolism, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts 02215
| | - Dae-Yeul Yu
- From the Disease Model Research Laboratory, Aging Research Center and World Class Institute, Korea Research Institute of Bioscience and Biotechnology, Daejeon 305-806, Republic of Korea
- the Department of Functional Genomics, University of Science and Technology, Daejeon 305-333, Republic of Korea
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Martin CM, Welge JA, Blackard JT. Hepatitis B virus (HBV) X gene diversity and evidence of recombination in HBV/HIV co-infected persons. J Med Virol 2011; 83:1142-50. [PMID: 21520141 DOI: 10.1002/jmv.22090] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/24/2011] [Indexed: 12/17/2022]
Abstract
The high frequency of mutation during hepatitis B virus (HBV) infection has resulted in 8 genotypes (A-H) with varying effects on disease severity and treatment efficacy. However, analysis of intrapatient HBV diversity is limited, especially during HIV co-infection. Therefore, a preliminary study was performed to analyze HBV X gene diversity in 17 HBV/HIV co-infected individuals. Phylogenetic analysis revealed HBV genotype A in 13 individuals (76.5%) or genotype E in 1 individual (5.9%). Additionally, 3 individuals were dually infected with HBV genotypes A and G (17.6%). Overall, higher genetic distance and entropy were observed in the X region and overlapping polymerase (Pol(X)) regions when compared to the PreS, S, and overlapping polymerase (Pol(PS) and Pol(S)) regions analyzed in the same patients as part of a previous study. In addition, multiple viral variants from 2 individuals with dual HBV infection did not group with either genotype A or G by phylogenetic analysis, indicating possible recombination. SimPlot bootscan analysis confirmed recombination breakpoints within the X gene in both individuals. Recombination between HBV genotypes may represent an important evolutionary strategy that enhances overall pathogenic potential and/or alters the downstream effects of the HBV X protein.
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Affiliation(s)
- Christina M Martin
- Division of Digestive Diseases, Department of Internal Medicine, University of Cincinnati College of Medicine, Cincinnati, Ohio, USA
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Shen H, Xu W, Luo W, Zhou L, Yong W, Chen F, Wu C, Chen Q, Han X. Upregulation of mdr1 gene is related to activation of the MAPK/ERK signal transduction pathway and YB-1 nuclear translocation in B-cell lymphoma. Exp Hematol 2011; 39:558-69. [PMID: 21300134 DOI: 10.1016/j.exphem.2011.01.013] [Citation(s) in RCA: 56] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2010] [Revised: 01/27/2011] [Accepted: 01/29/2011] [Indexed: 11/30/2022]
Abstract
OBJECTIVE Multidrug resistance (MDR) in human B-cell lymphoma constitutes a major obstacle to the effectiveness of chemotherapy. The aim of this study was to investigate the molecular mechanism of MDR in B-cell lymphoma. MATERIALS AND METHODS The B-cell lymphoma MDR sublines were developed by exposing the parental Daudi cells to stepwise increasing concentrations of doxorubicin. Interaction of Y-box binding protein-1 (YB-1) with the Y-box motif of the mdr1 gene promoters was studied by electrophoretic mobility shift assay. The effects of YB-1 on mdr1 promoter activity were examined by luciferase assay. After silencing of YB-1 gene by shRNA, the role of YB-1 nuclear translocation in the formation of induced MDR was examined. Expression of mdr1 and YB-1 was examined further after Daudi cells were pretreated with mitogen-activated protein kinase (MAPK) inhibitor PD98059 for 1 hour. RESULTS Doxorubicin-resistant sublines was generated from the Daudi cell line by stepwise selection in doxorubicin. We found that acquisition of MDR is associated with enhanced YB-1 nuclear translocation and MAPK/extracellular signal-regulated kinase (ERK) activity. Electrophoretic mobility shift assay revealed that doxorubicin increased binding of YB-1 to the Y-box of mdr1 promoter. Luciferase reporter assays demonstrated that the Y-box region is essential for YB-1 regulation of mdr1 expression. The introduction of exogenous YB-1 shRNA into Daudi cells resulted in decreased levels of the expression of mdr1 gene and P-glycoprotein induced by doxorubicin. When Daudi cells were pretreated with MAPK inhibitor PD98059, the phosphorylation of ERK was effectively inhibited as well as the nuclear translocation of YB-1 and the expression of mdr1 gene. CONCLUSION Doxorubicin can increase expression of mdr1/P-glycoprotein through activating MAPK/ERK transduction pathway, then increasing expression of YB-1, inducing YB-1 nuclear translocation, and enhancing DNA-binding activity of YB-1.
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Affiliation(s)
- Huiling Shen
- Key Laboratory of Human Functional Genomics of Jiangsu Province, Nanjing Medical University, 140 Hanzhong Road, Nanjing, PR China
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Chen WN, Chen JY, Lin WS, Lin JY, Lin X. Hepatitis B doubly spliced protein, generated by a 2.2 kb doubly spliced hepatitis B virus RNA, is a pleiotropic activator protein mediating its effects via activator protein-1- and CCAAT/enhancer-binding protein-binding sites. J Gen Virol 2010; 91:2592-600. [PMID: 20538904 DOI: 10.1099/vir.0.022517-0] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023] Open
Abstract
The 2.2 kb doubly spliced defective hepatitis B virus (HBV) genome is frequently detected in the serum of patients with chronic hepatitis B. However, the biological significance of this type of defective genome is not well understood. In this study, expression of the hepatitis B doubly spliced protein (HBDSP) was confirmed from the 2.2 kb doubly spliced defective HBV genome, which was isolated and transfected into Huh-7 hepatoma cells. To explore the potential pathogenicity of HBDSP, hepatocellular proteins interacting with HBDSP were screened by a yeast two-hybrid assay. Unexpectedly, HBDSP could transactivate the GAL4-responsive element, and deletion mapping revealed that the fragment located between residues Leu-48 and Gln-75 of HBDSP was crucial for transactivation activity. In Huh-7 hepatoma cells, HBDSP localized predominantly to the cytoplasm and showed transactivating effects on the cytomegalovirus immediate-early promoter, simian virus 40 enhancer/promoter and HBV regulatory elements including the S1 promoter, S2 promoter, Enhancer I and core upstream regulatory sequences. Further studies revealed that the transactivating activities were mediated by activator protein-1- and CCAAT/enhancer-binding protein-binding sites. These findings suggest that HBDSP is a pleiotropic activator protein that can potentially serve as an HBV virulence factor.
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Affiliation(s)
- Wan-Nan Chen
- Key Laboratory of tumor Microbiology, Department of Medical Microbiology, Fujian Medical University, Fuzhou 350004, Fujian, PR China
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Wu MH, Ma WL, Hsu CL, Chen YL, Ou JHJ, Ryan CK, Hung YC, Yeh S, Chang C. Androgen receptor promotes hepatitis B virus-induced hepatocarcinogenesis through modulation of hepatitis B virus RNA transcription. Sci Transl Med 2010; 2:32ra35. [PMID: 20484730 PMCID: PMC3032595 DOI: 10.1126/scitranslmed.3001143] [Citation(s) in RCA: 159] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Hepatitis B virus (HBV)-induced hepatitis and carcinogen-induced hepatocellular carcinoma (HCC) are associated with serum androgen concentration. However, how androgen or the androgen receptor (AR) contributes to HBV-induced hepatocarcinogenesis remains unclear. We found that hepatic AR promotes HBV-induced hepatocarcinogenesis in HBV transgenic mice that lack AR only in the liver hepatocytes (HBV-L-AR(-/y)). HBV-L-AR(-/y) mice that received a low dose of the carcinogen N'-N'-diethylnitrosamine (DEN) have a lower incidence of HCC and present with smaller tumor sizes, fewer foci formations, and less alpha-fetoprotein HCC marker than do their wild-type HBV-AR(+/y) littermates. We found that hepatic AR increases the HBV viral titer by enhancing HBV RNA transcription through direct binding to the androgen response element near the viral core promoter. This activity forms a positive feedback mechanism with cooperation with its downstream target gene HBx protein to promote hepatocarcinogenesis. Administration of a chemical compound that selectively degrades AR, ASC-J9, was able to suppress HCC tumor size in DEN-HBV-AR(+/y) mice. These results demonstrate that targeting the AR, rather than the androgen, could be developed as a new therapy to battle HBV-induced HCC.
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MESH Headings
- Androgen Receptor Antagonists
- Animals
- Antineoplastic Agents/pharmacology
- Base Sequence
- Carcinoma, Hepatocellular/chemically induced
- Carcinoma, Hepatocellular/genetics
- Carcinoma, Hepatocellular/metabolism
- Carcinoma, Hepatocellular/prevention & control
- Carcinoma, Hepatocellular/virology
- Cell Transformation, Viral/genetics
- Curcumin/analogs & derivatives
- Curcumin/pharmacology
- Diethylnitrosamine
- Disease Models, Animal
- Gene Expression Regulation, Neoplastic
- Hep G2 Cells
- Hepatitis B/complications
- Hepatitis B/genetics
- Hepatitis B virus/genetics
- Humans
- Liver/metabolism
- Liver/pathology
- Liver/virology
- Liver Neoplasms/chemically induced
- Liver Neoplasms/genetics
- Liver Neoplasms/metabolism
- Liver Neoplasms/prevention & control
- Liver Neoplasms/virology
- Male
- Mice
- Mice, Knockout
- Mice, Transgenic
- Molecular Sequence Data
- Promoter Regions, Genetic
- RNA, Viral/metabolism
- Receptors, Androgen/deficiency
- Receptors, Androgen/genetics
- Receptors, Androgen/metabolism
- Time Factors
- Transcription, Genetic
- Transfection
- Tumor Burden
- Viral Load
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Affiliation(s)
- Ming-Heng Wu
- Institute of Basic Medical Sciences, National Cheng Kung University, Tainan 701, Taiwan
- George Whipple Lab for Cancer Research, Departments of Pathology and Urology and Wilmot Cancer Center, University of Rochester Medical Center, Rochester, NY 14642, USA
| | - Wen-Lung Ma
- George Whipple Lab for Cancer Research, Departments of Pathology and Urology and Wilmot Cancer Center, University of Rochester Medical Center, Rochester, NY 14642, USA
- Sex Hormone Research Center, Graduate Institute of Clinical Medical Science, Department of Obstetrics and Gynecology, China Medical University/Hospital, Taichung 404, Taiwan
| | - Cheng-Lung Hsu
- George Whipple Lab for Cancer Research, Departments of Pathology and Urology and Wilmot Cancer Center, University of Rochester Medical Center, Rochester, NY 14642, USA
- Division of Hematology-Oncology, Department of Internal Medicine, Chang Gung University/Memorial Hospital, Taoyuan 33305, Taiwan
| | - Yuh-Ling Chen
- Institute of Basic Medical Sciences, National Cheng Kung University, Tainan 701, Taiwan
- George Whipple Lab for Cancer Research, Departments of Pathology and Urology and Wilmot Cancer Center, University of Rochester Medical Center, Rochester, NY 14642, USA
| | - Jing-Hsiung James Ou
- Department of Molecular Microbiology and Immunology, University of Southern California, Los Angeles, CA 90089, USA
| | - Charlotte Kathryn Ryan
- George Whipple Lab for Cancer Research, Departments of Pathology and Urology and Wilmot Cancer Center, University of Rochester Medical Center, Rochester, NY 14642, USA
| | - Yao-Ching Hung
- Sex Hormone Research Center, Graduate Institute of Clinical Medical Science, Department of Obstetrics and Gynecology, China Medical University/Hospital, Taichung 404, Taiwan
| | - Shuyuan Yeh
- George Whipple Lab for Cancer Research, Departments of Pathology and Urology and Wilmot Cancer Center, University of Rochester Medical Center, Rochester, NY 14642, USA
| | - Chawnshang Chang
- George Whipple Lab for Cancer Research, Departments of Pathology and Urology and Wilmot Cancer Center, University of Rochester Medical Center, Rochester, NY 14642, USA
- Sex Hormone Research Center, Graduate Institute of Clinical Medical Science, Department of Obstetrics and Gynecology, China Medical University/Hospital, Taichung 404, Taiwan
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Hepatitis B virus X protein promotes liver cell proliferation via a positive cascade loop involving arachidonic acid metabolism and p-ERK1/2. Cell Res 2010; 20:563-75. [DOI: 10.1038/cr.2010.49] [Citation(s) in RCA: 58] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023] Open
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Abstract
Viruses of the Paramyxoviridae family bind to their host cells by using hemagglutinin-neuraminidase (HN), which enhances fusion protein (F)-mediated membrane fusion. Although respiratory syncytial virus and parainfluenza virus 5 of this family are suggested to trigger host cell signaling during infection, the virus-induced intracellular signals dictating virus-cell fusion await elucidation. Using an F- or HN-F-containing reconstituted envelope of Sendai virus, another paramyxovirus, we revealed the role and regulation of AKT1 and Raf/MEK/ERK cascades during viral fusion with liver cells. Our observation that extracellular signal-regulated kinase (ERK) activation promotes viral fusion via ezrin-mediated cytoskeletal rearrangements, whereas AKT1 attenuates fusion by promoting phosphorylation of F protein, indicates a counteractive regulation of viral fusion by reciprocal activation of AKT1 and mitogen-activated protein kinase (MAPK) cascades, establishing a novel conceptual framework for a therapeutic strategy.
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Khattar E, Kumar V. Mitogenic regulation of p27(Kip1) gene is mediated by AP-1 transcription factors. J Biol Chem 2009; 285:4554-61. [PMID: 19959471 DOI: 10.1074/jbc.m109.029280] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The abundance of cyclin-dependent kinase inhibitor p27(Kip1) during the cell cycle determines whether cells will proliferate or become quiescent. Although the post-translational regulation of p27(Kip1) is well established, its transcriptional regulation is poorly understood. Here, we report that mitogenic stimulation of quiescent HEK293 and Huh7 cells showed a rapid decline in the levels of p27(Kip1) transcript by 2.4 +/- 0.1-fold. Inhibition of the p27(Kip1) gene in response to mitogens involved transcriptional down-regulation and required newly synthesized protein(s). Mutation of the AP-1 element at position -469 in the human p27(Kip1) promoter abrogated the effect of mitogens. The recruitment of the AP-1 complex to the p27(Kip1) promoter was confirmed by in vitro DNA binding and chromatin immunoprecipitation studies. Reporter gene analysis combined with enforced expression of Jun/Fos proteins suggested the involvement of Jun/Fos heterodimer in the transrepression process. Both MAPK and phosphatidylinositol 3-kinase signaling pathways appeared to mediate p27(Kip1) transcription. Furthermore, hepatitis B virus X protein-mediated down-regulation of p27(Kip1) in a transgenic environment correlated with an increase in c-Fos levels, reiterating the physiological relevance of AP-1 in the transcriptional regulation of p27(Kip1). Collectively, our studies present the first evidence demonstrating the role of the AP-1 complex in transcriptional down-regulation of the p27(Kip1) gene following mitogenic stimulation.
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Affiliation(s)
- Ekta Khattar
- Virology Group, International Centre for Genetic Engineering and Biotechnology, Aruna Asaf Ali Marg, New Delhi 110067, India
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Chen F, Beezhold K, Castranova V. JNK1, a potential therapeutic target for hepatocellular carcinoma. Biochim Biophys Acta Rev Cancer 2009; 1796:242-51. [PMID: 19591900 DOI: 10.1016/j.bbcan.2009.06.005] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2009] [Revised: 06/21/2009] [Accepted: 06/27/2009] [Indexed: 02/08/2023]
Abstract
Hepatocellular carcinoma (HCC) is the third leading cause of cancer death worldwide. Despite tremendous efforts to diagnose and institute new treatment regimens, the prognosis is still extremely poor. Therefore, knowledge of the molecular mechanisms governing the initiation, maintenance and progression of HCC is urgently needed. Recently, several groups have attributed an important role for c-Jun N-terminal kinase 1 (JNK1) in the pathogenesis of human HCC and its close association with the expression of HCC signature genes. In this review the various associations between JNK1 and HCC are discussed with the hope that targeting this pivotal kinase may lead to novel therapeutic approaches for this fatal disease.
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Affiliation(s)
- Fei Chen
- Laboratory of Cancer Signaling and Epigenetics, Health Effects Laboratory Division, Pathology and Physiology Research Branch, National Institute for Occupational Safety and Health, 1095 Willowdale Road, Morgantown, WV 26505, USA.
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Kuang E, Wu F, Zhu F. Mechanism of sustained activation of ribosomal S6 kinase (RSK) and ERK by kaposi sarcoma-associated herpesvirus ORF45: multiprotein complexes retain active phosphorylated ERK AND RSK and protect them from dephosphorylation. J Biol Chem 2009; 284:13958-13968. [PMID: 19304659 PMCID: PMC2679495 DOI: 10.1074/jbc.m900025200] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2009] [Revised: 03/19/2009] [Indexed: 12/23/2022] Open
Abstract
As obligate intracellular parasites, viruses exploit diverse cellular signaling machineries, including the mitogen-activated protein-kinase pathway, during their infections. We have demonstrated previously that the open reading frame 45 (ORF45) of Kaposi sarcoma-associated herpesvirus interacts with p90 ribosomal S6 kinases (RSKs) and strongly stimulates their kinase activities ( Kuang, E., Tang, Q., Maul, G. G., and Zhu, F. (2008) J. Virol. 82, 1838-1850 ). Here, we define the mechanism by which ORF45 activates RSKs. We demonstrated that binding of ORF45 to RSK increases the association of extracellular signal-regulated kinase (ERK) with RSK, such that ORF45, RSK, and ERK formed high molecular mass protein complexes. We further demonstrated that the complexes shielded active pERK and pRSK from dephosphorylation. As a result, the complex-associated RSK and ERK were activated and sustained at high levels. Finally, we provide evidence that this mechanism contributes to the sustained activation of ERK and RSK in Kaposi sarcoma-associated herpesvirus lytic replication.
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Affiliation(s)
- Ersheng Kuang
- Department of Biological Science, Florida State University, Tallahassee, Florida 32306-4370
| | - Fayi Wu
- Department of Biological Science, Florida State University, Tallahassee, Florida 32306-4370
| | - Fanxiu Zhu
- Department of Biological Science, Florida State University, Tallahassee, Florida 32306-4370.
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Subramanian N, Mani P, Roy S, Gnanasundram SV, Sarkar DP, Das S. Targeted delivery of hepatitis C virus-specific short hairpin RNA in mouse liver using Sendai virosomes. J Gen Virol 2009; 90:1812-1819. [PMID: 19297606 DOI: 10.1099/vir.0.010579-0] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Internal ribosome entry site (IRES)-mediated translation of input viral RNA is the initial required step for the replication of the positive-stranded genome of hepatitis C virus (HCV). We have shown previously the importance of the GCAC sequence near the initiator AUG within the stem and loop IV (SLIV) region in mediating ribosome assembly on HCV RNA. Here, we demonstrate selective inhibition of HCV-IRES-mediated translation using short hairpin (sh)RNA targeting the same site within the HCV IRES. sh-SLIV showed significant inhibition of viral RNA replication in a human hepatocellular carcinoma (Huh7) cell line harbouring a HCV monocistronic replicon. More importantly, co-transfection of infectious HCV-H77s RNA and sh-SLIV in Huh7.5 cells successfully demonstrated a significant decrease in viral RNA in HCV cell culture. Additionally, we report, for the first time, the targeted delivery of sh-SLIV RNA into mice liver using Sendai virosomes and demonstrate selective inhibition of HCV-IRES-mediated translation. Results provide the proof of concept that Sendai virosomes could be used for the efficient delivery of shRNAs into liver tissue to block HCV replication.
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Affiliation(s)
- Nithya Subramanian
- Department of Microbiology and Cell Biology, Indian Institute of Science, Bangalore 560012, India
| | - Prashant Mani
- Department of Biochemistry, University of Delhi, South Campus, New Delhi 110021, India
| | - Swagata Roy
- Department of Microbiology and Cell Biology, Indian Institute of Science, Bangalore 560012, India
| | | | - Debi P Sarkar
- Department of Biochemistry, University of Delhi, South Campus, New Delhi 110021, India
| | - Saumitra Das
- Department of Microbiology and Cell Biology, Indian Institute of Science, Bangalore 560012, India
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A histidine switch in hemagglutinin-neuraminidase triggers paramyxovirus-cell membrane fusion. J Virol 2008; 83:1727-41. [PMID: 19052089 DOI: 10.1128/jvi.02026-08] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Most paramyxovirus fusion proteins require coexpression of and activation by a homotypic attachment protein, hemagglutinin-neuraminidase (HN), to promote membrane fusion. However, the molecular mechanism of the activation remains unknown. We previously showed that the incorporation of a monohistidylated lipid into F-virosome (Sendai viral envelope containing only fusion protein) enhanced its fusion to hepatocytes, suggesting that the histidine residue in the lipid accelerated membrane fusion. Therefore, we explored whether a histidine moiety in HN could similarly direct activation of the fusion protein. In membrane fusion assays, the histidine substitution mutants of HN (H247A of Sendai virus and H245A of human parainfluenza virus 3) had impaired membrane fusion promotion activity without significant changes in other biological activities. Synthetic 30-mer peptides corresponding to regions of the two HN proteins containing these histidine residues rescued the fusion promoting activity of the mutants, whereas peptides with histidine residues substituted by alanine did not. These histidine-containing peptides also activated F-virosome fusion with hepatocytes both in the presence and in the absence of mutant HN in the virosome. We provide evidence that the HN-mimicking peptides promote membrane fusion, revealing a specific histidine "switch" in HN that triggers fusion.
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Ye L, Dong N, Wang Q, Xu Z, Cai N, Wang H, Zhang X. Progressive changes in hepatoma cells stably transfected with hepatitis B virus X gene. Intervirology 2008; 51:50-8. [PMID: 18334850 DOI: 10.1159/000120289] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2007] [Accepted: 12/20/2007] [Indexed: 12/27/2022] Open
Abstract
OBJECTIVE The aim of this study is to investigate the molecular mechanism of hepatocellular carcinoma (HCC) development induced by hepatitis B virus X protein (HBx). METHODS We previously established a H7402-X cell line that constitutively expresses HBx protein. In the present study, H7402-X gene expression profiles and proteins were examined using cDNA microarrays and Western blot analysis. Apoptosis was induced by adriamycin in H7402-X cells. The transcriptional activities of NF-kappaB and AP-1 were examined using a luciferase reporter gene. RESULTS The DNA expression profiles identified candidate genes showing aberrant expression in cells overexpressing HBx. Western blot analysis showed that cyclin D, cyclin E, survivin, Bcl-2, and PCNA were up-regulated, whereas p27 was down-regulated in H7402-X cells. Treatment with RNAi targeting HBx mRNA led to the down-regulation of these genes. H7402-X cells were resistant to adriamycin-induced apoptosis. Luciferase reporter gene analysis revealed that HBx induces the transcriptional activities of NF-kappaB and AP-1. CONCLUSION Our data provide additional insight into cellular targets of HBx, which allows a better understanding of HBx function and the progressive changes during HBx-mediated hepatocarcinogenesis.
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Affiliation(s)
- Lihong Ye
- Department of Biochemistry, College of Life Sciences, Nankai University, Tianjin, PR China
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Kuang E, Tang Q, Maul GG, Zhu F. Activation of p90 ribosomal S6 kinase by ORF45 of Kaposi's sarcoma-associated herpesvirus and its role in viral lytic replication. J Virol 2008; 82:1838-50. [PMID: 18057234 PMCID: PMC2258723 DOI: 10.1128/jvi.02119-07] [Citation(s) in RCA: 77] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2007] [Accepted: 11/26/2007] [Indexed: 01/04/2023] Open
Abstract
The extracellular signal-regulated kinase (ERK) mitogen-activated protein kinase (MAPK) pathway is essential for infection by a variety of viruses. The p90 ribosomal S6 kinases (RSKs) are direct substrates of ERK and functional mediators of ERK MAPK signaling, but their roles in viral infection have never been examined. We demonstrate that ORF45 of Kaposi's sarcoma-associated herpesvirus (KSHV) interacts with RSK1 and RSK2 and strongly stimulates their kinase activities. The activation of RSK by ORF45 is correlated with ERK activation but does not require MEK. We further demonstrate that RSK1/RSK2 is activated during KSHV primary infection and reactivation from latency; a subset of RSK1/RSK2 is present in the viral replication compartment in the nucleus. Depletion of RSK1/RSK2 by small interfering RNA or the specific inhibitor BI-D1870 suppresses KSHV lytic gene expression and progeny virion production, suggesting an essential role of RSK1/RSK2 in KSHV lytic replication.
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Affiliation(s)
- Ersheng Kuang
- Department of Biological Science, Florida State University, 89 Chieftan Way, Tallahassee, FL 32306-4370, USA
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Zhou F, Ren JL, Lu YP, Chen MY, Xu HZ, Pan JS, Cai JY, Dong J. Interaction between fibrinogen alpha chain and the whole S protein of hepatitis B virus. Shijie Huaren Xiaohua Zazhi 2008; 16:2581. [DOI: 10.11569/wcjd.v16.i23.2581] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
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Fischer ANM, Fuchs E, Mikula M, Huber H, Beug H, Mikulits W. PDGF essentially links TGF-beta signaling to nuclear beta-catenin accumulation in hepatocellular carcinoma progression. Oncogene 2006; 26:3395-405. [PMID: 17130832 DOI: 10.1038/sj.onc.1210121] [Citation(s) in RCA: 113] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
The cooperation of Ras - extracellular signal-regulated kinase/mitogen-activated protein kinase and transforming growth factor (TGF)-beta signaling provokes an epithelial to mesenchymal transition (EMT) of differentiated p19(ARF) null hepatocytes, which is accompanied by a shift in malignancy and gain of metastatic properties. Upon EMT, TGF-beta induces the secretion and autocrine regulation of platelet-derived growth factor (PDGF) by upregulation of PDGF-A and both PDGF receptors. Here, we demonstrate by loss-of-function analyses that PDGF provides adhesive and migratory properties in vitro as well as proliferative stimuli during tumor formation. PDGF signaling resulted in the activation of phosphatidylinositol-3 kinase, and furthermore associated with nuclear beta-catenin accumulation upon EMT. Hepatocytes expressing constitutively active beta-catenin or its negative regulator Axin were employed to study the impact of nuclear beta-catenin. Unexpectedly, active beta-catenin failed to accelerate proliferation during tumor formation, but in contrast, correlated with growth arrest. Nuclear localization of beta-catenin was accompanied by strong expression of the Cdk inhibitor p16(INK4A) and the concomitant induction of the beta-catenin target genes cyclin D1 and c-myc. In addition, active beta-catenin revealed protection of malignant hepatocytes against anoikis, which provides a prerequisite for the dissemination of carcinoma. From these data, we conclude that TGF-beta acts tumor progressive by induction of PDGF signaling and subsequent activation of beta-catenin, which endows a subpopulation of neoplastic hepatocytes with features of cancer stem cells..
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Affiliation(s)
- A N M Fischer
- Department of Medicine I, Division: Institute of Cancer Research, Medical University of Vienna, Vienna, Austria
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N/A, 林 纳. N/A. Shijie Huaren Xiaohua Zazhi 2006; 14:2579-2585. [DOI: 10.11569/wcjd.v14.i26.2579] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
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Abstract
Hepatocellular carcinoma is among the most lethal and prevalent cancers in the human population. Despite its significance, there is only an elemental understanding of the molecular, cellular and environmental mechanisms that drive disease pathogenesis, and there are only limited therapeutic options, many with negligible clinical benefit. This Review summarizes the current state of knowledge of this, the most common and dreaded liver neoplasm, and highlights the principal challenges and scientific opportunities that are relevant to controlling this accelerating global health crisis.
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Affiliation(s)
- Paraskevi A Farazi
- Department of Genetics, Division of Medical Sciences, Harvard University, Boston, Massachusetts 02115, USA
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Affiliation(s)
- Mark Branda
- Liver Research Center, Department of Medicine, Rhode Island Hospital and Brown Medical School, Providence 02903, USA
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Tanaka Y, Kanai F, Ichimura T, Tateishi K, Asaoka Y, Guleng B, Jazag A, Ohta M, Imamura J, Ikenoue T, Ijichi H, Kawabe T, Isobe T, Omata M. The hepatitis B virus X protein enhances AP-1 activation through interaction with Jab1. Oncogene 2006; 25:633-642. [PMID: 16247477 DOI: 10.1038/sj.onc.1209093] [Citation(s) in RCA: 72] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2005] [Revised: 07/27/2005] [Accepted: 08/03/2005] [Indexed: 02/06/2023]
Abstract
Hepatitis B virus X protein (HBx) has many cellular functions and is a major factor in hepatitis and hepatocellular carcinoma caused by HBV infection. A proteomic approach was used to search for HBx-interacting proteins in order to elucidate the molecular mechanism of hepatocarcinogenesis. HBx was attached to myc and flag tags (MEF tags) and expressed in 293T cells; the protein complex formed within the cells was purified and characterized by mass spectrometry. COP9 signalosome (CSN) subunits 3 and 4 were subsequently identified as HBx-interacting proteins. In addition, CSN subunit 5, Jun activation domain-binding protein 1 (Jab1), was shown to be a novel cellular target of HBx. In vivo and in vitro interactions between HBx and Jab1 were confirmed by standard immunoprecipitation and GST pull-down assays. An analysis of HBx deletion constructs showed that amino acids 30-125 of HBx were responsible for binding to Jab1. Confocal laser microscopy demonstrated that HBx was mainly localized in the cytoplasm, while Jab1 was found mainly in the nucleus and partially in the cytoplasm, and that the two proteins colocalized in the cytoplasm. The cotransfection of HBx and Jab1 resulted in substantial activator protein 1 (AP-1) activation and knockdown of endogenous Jab1 attenuated AP-1 activation caused by HBx. In addition, the coexpression of HBx and Jab1 potentiated phosphorylation of JNK, leading to the subsequent phosphorylation of c-Jun, whereas the level of c-Jun and JNK phosphorylation induced by HBx was decreased in Jab1 knockdown cells. These results suggest that the interaction between HBx and Jab1 enhances HBx-mediated AP-1 activation.
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Affiliation(s)
- Y Tanaka
- Department of Gastroenterology, Graduate School of Medicine, University of Tokyo, Japan
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