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Tsai HW, Lee YP, Yen CJ, Cheng KH, Huang CJ, Huang W. The Serum Hepatitis B Virus Large Surface Protein as High-Risk Recurrence Biomarker for Hepatoma after Curative Surgery. Int J Mol Sci 2022; 23:ijms23105376. [PMID: 35628188 PMCID: PMC9140564 DOI: 10.3390/ijms23105376] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2022] [Revised: 05/09/2022] [Accepted: 05/09/2022] [Indexed: 11/26/2022] Open
Abstract
Chronic hepatitis B (CHB) virus infection is the most important cause of HCC and is also associated with tumor progression. The development of viral biomarkers for HCC prognosis is critical in evaluating relative risks to recurrence in the CHB HCC patients. We report that the large HBV surface protein (LHBS) expression increased in the tumors, implicating that it played a significant role in tumor development. To detect the LHBS in serum and evaluate its association with HCC progression, we developed a sandwich ELISA method for LHBS. The mouse monoclonal antibodies for the pre-S1, pre-S2, and HBS regions were in-house generated and constructed into a chemiluminescent sandwich ELISA system, which allowed sensitive and quantitative measurement of the protein. Using this ELISA assay, we estimated the expression of LHBS in CHB and HCC patients. We found that the serum LHBS level was correlated with the HBS but not the viral titer in serum, indicating that HBV surface proteins’ expression does not mainly depend on viral replication. Moreover, both serum LHBS and HBS levels were lower in the HCC patients than in the CHB. The liver LHBS signals, detected by immunohistochemical staining, showed significant correlations with the serum LHBS and HBS levels. In addition, the more elevated serum LHBS but not HBS level was significantly associated with cirrhosis and worse disease-free and overall survival rates, based on the multivariate analysis. Conclusion: LHBS plays a specific role in tumor progression and is an independent parameter associated with HCC recurrence. Serum LHBS represents a novel noninvasive biomarker for HCC patients with a worse prognosis after surgery.
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Affiliation(s)
- Hung-Wen Tsai
- Department of Pathology, National Cheng Kung University Hospital, College of Medicine, National Cheng Kung University, Tainan 70101, Taiwan; (H.-W.T.); (K.-H.C.)
| | - Yun-Ping Lee
- Department of Medical Laboratory Science and Biotechnology, College of Medicine, National Cheng Kung University, Tainan 70101, Taiwan;
| | - Chia-Jui Yen
- Division of Hematology and Oncology, Department of Internal Medicine, National Cheng Kung University Hospital, College of Medicine, National Cheng Kung University, Tainan 70101, Taiwan;
| | - Kuang-Hsiung Cheng
- Department of Pathology, National Cheng Kung University Hospital, College of Medicine, National Cheng Kung University, Tainan 70101, Taiwan; (H.-W.T.); (K.-H.C.)
| | - Chien-Jung Huang
- Department of Internal Medicine, Taipei City Hospital, Taipei 10341, Taiwan;
| | - Wenya Huang
- Department of Pathology, National Cheng Kung University Hospital, College of Medicine, National Cheng Kung University, Tainan 70101, Taiwan; (H.-W.T.); (K.-H.C.)
- Department of Medical Laboratory Science and Biotechnology, College of Medicine, National Cheng Kung University, Tainan 70101, Taiwan;
- Institute of Basic Medical Science, College of Medicine, National Cheng Kung University, Tainan 70101, Taiwan
- Correspondence: ; Tel.: +886-6-235-3535 (ext. 5766)
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Liu GZ, Xu XW, Tao SH, Gao MJ, Hou ZH. HBx facilitates ferroptosis in acute liver failure via EZH2 mediated SLC7A11 suppression. J Biomed Sci 2021; 28:67. [PMID: 34615538 PMCID: PMC8495979 DOI: 10.1186/s12929-021-00762-2] [Citation(s) in RCA: 37] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2021] [Accepted: 09/15/2021] [Indexed: 12/15/2022] Open
Abstract
Background Acute liver failure (ALF) is a syndrome of severe hepatocyte injury with high rate of mortality. Hepatitis B virus (HBV) infection is the major cause of ALF worldwide, however, the underlying mechanism by which HBV infection leads to ALF has not been fully disclosed. Methods D-GalN-induced hepatocyte injury model and LPS/D-GalN-induced ALF mice model were used to investigate the effects of HBV X protein (HBx) in vitro and in vivo, respectively. Cell viability and the levels of Glutathione (GSH), malondialdehyde (MDA) and iron were measured using commercial kits. The expression of ferroptosis-related molecules were detected by qRT-PCR and western blotting. Epigenetic modification and protein interaction were detected by chromatin immunoprecipitation (ChIP) assay and co-immunoprecipitation (co-IP), respectively. Mouse liver function was assessed by measuring aspartate aminotransferase (AST) and alanine aminotransferase (ALT). The histological changes in liver tissues were monitored by hematoxylin and eosin (H&E) staining, and SLC7A11 immunoreactivity was assessed by immunohistochemistry (IHC) analysis. Results D-GalN triggered ferroptosis in primary hepatocytes. HBx potentiated D-GalN-induced hepatotoxicity and ferroptosis in vitro, and it suppressed SLC7A11 expression through H3K27me3 modification by EZH2. In addition, EZH2 inhibition or SLC7A11 overexpression attenuated the effects of HBx on D-GalN-induced ferroptosis in primary hepatocytes. The ferroptosis inhibitor ferrostatin-1 (Fer-1) protected against ALF and ferroptosis in vivo. By contrast, HBx exacerbates LPS/D-GalN-induced ALF and ferroptosis in HBx transgenic (HBx-Tg) mice. Conclusion HBx facilitates ferroptosis in ALF via EZH2/H3K27me3-mediated SLC7A11 suppression.
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Affiliation(s)
- Guo-Zhen Liu
- Department of Infectious Diseases, Xiangya Hospital, Central South University, No.87, Xiangya Road, Kaifu District, Changsha, 410008, Hunan, China
| | - Xu-Wen Xu
- Department of Infectious Diseases, Nanfang Hospital, Southern Medical University, Guangzhou, 510515, Guangdong, China
| | - Shu-Hui Tao
- Department of Liver Diseases, Shenzhen Hospital, Southern Medical University, Shenzhen, 518100, Guangdong, China
| | - Ming-Jian Gao
- Department of Infectious Diseases, Xiangya Hospital, Central South University, No.87, Xiangya Road, Kaifu District, Changsha, 410008, Hunan, China
| | - Zhou-Hua Hou
- Department of Infectious Diseases, Xiangya Hospital, Central South University, No.87, Xiangya Road, Kaifu District, Changsha, 410008, Hunan, China.
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3
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Bao CY, Hung HC, Chen YW, Fan CY, Huang CJ, Huang W. Requirement of cyclin-dependent kinase function for hepatitis B virus cccDNA synthesis as measured by digital PCR. Ann Hepatol 2021; 19:280-286. [PMID: 31964596 DOI: 10.1016/j.aohep.2019.12.005] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/24/2019] [Revised: 12/20/2019] [Accepted: 12/20/2019] [Indexed: 02/04/2023]
Abstract
INTRODUCTION AND OBJECTIVES HBV covalently closed circular (ccc) DNA is the key player in viral persistence and an important predictive biomarker for hepatitis relapse. Precise quantification of intracellular cccDNA is challenging because cccDNA is present in very low levels in hepatocytes, where it also co-exists with a large excess amount of relaxed circular (rc) DNA. We aimed to develop a highly sensitive cccDNA detection method for cccDNA quantification by digital PCR (dPCR). PATIENTS OR MATERIALS AND METHODS A standard plasmid containing the whole HBV genome in the closed circular conformation was employed to characterize the performance of dPCR. rcDNA in the growth medium of HBV-producing HepAD38 cells was used as a matrix for cccDNA detection. Intrahepatic cccDNA measurement by dPCR and qPCR was performed to determine the correlation of the analysis results for the two methods. RESULTS The limit of detection (LOD) of the cccDNA dPCR was 1.05copy/μl, and the linear range of detection was 1.02×104copies/μl, achieving a dynamic detection range of 104-fold. cccDNA measurement using excess rcDNA as the matrix did not reveal false-positive detection, indicating that dPCR was highly specific. In the HepAD38 cells, the cccDNA levels measured by dPCR were highly correlated with those measured by qPCR but had a higher sensitivity. The CDK inhibitor AZD-5438 was found to block intracellular cccDNA synthesis. CONCLUSIONS Dpcr greatly improved the sensitivity and specificity of cccDNA detection. Host CDK activities are likely required for cccDNA synthesis. dPCR can potentially be applied for drug screening for effective cccDNA inhibitors.
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Affiliation(s)
- Ching-Yu Bao
- Department of Medical Laboratory Science and Biotechnology, College of Medicine, National Cheng Kung University, Tainan, Taiwan
| | - Hsu-Chin Hung
- Department of Medical Laboratory Science and Biotechnology, College of Medicine, National Cheng Kung University, Tainan, Taiwan
| | - Yi-Wen Chen
- Cold Spring Biotech Corp, New Taipei City, Taiwan
| | | | - Chien-Jung Huang
- Department of Internal Medicine, Taipei City Hospital, Taipei, Taiwan
| | - Wenya Huang
- Department of Medical Laboratory Science and Biotechnology, College of Medicine, National Cheng Kung University, Tainan, Taiwan; Institute of Basic Medicine, National Cheng Kung University, Tainan, Taiwan; Department of Pathology, National Cheng Kung University Hospital, Tainan, Taiwan.
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4
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Dong KS, Chen Y, Yang G, Liao ZB, Zhang HW, Liang HF, Chen XP, Dong HH. TGF-β1 accelerates the hepatitis B virus X-induced malignant transformation of hepatic progenitor cells by upregulating miR-199a-3p. Oncogene 2019; 39:1807-1820. [PMID: 31740785 PMCID: PMC7033045 DOI: 10.1038/s41388-019-1107-9] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2018] [Revised: 10/29/2019] [Accepted: 11/06/2019] [Indexed: 12/25/2022]
Abstract
Increasing evidence has suggested that liver cancer arises partially from transformed hepatic progenitor cells (HPCs). However, the detailed mechanisms underlying HPC transformation are poorly understood. In this study, we provide evidence linking the coexistence of hepatitis B virus X protein (HBx) and transforming growth factor beta 1 (TGF-β1) with miR-199a-3p in the malignant transformation of HPCs. The examination of liver cancer specimens demonstrated that HBx and TGF-β1 expression was positively correlated with epithelial cell adhesion molecule (EpCAM) and cluster of differentiation 90 (CD90). Importantly, EpCAM and CD90 expression was much higher in the specimens expressing both high HBx and high TGF-β1 than in those with high HBx or high TGF-β1 and the double-low-expression group. HBx and TGF-β1 double-high expression was significantly associated with poor prognosis in primary liver cancer. We also found that HBx and TGF-β1 induced the transformation of HPCs into hepatic cancer stem cells and promoted epithelial–mesenchymal transformation, which was further enhanced by concomitant HBx and TGF-β1 exposure. Moreover, activation of the c-Jun N-terminal kinase (JNK)/c-Jun pathway was involved in the malignant transformation of HPCs. miR-199a-3p was identified as a significantly upregulated microRNA in HPCs upon HBx and TGF-β1 exposure, which were shown to promote miR-199a-3p expression via c-Jun-mediated activation. Finally, we found that miR-199a-3p was responsible for the malignant transformation of HPCs. In conclusion, our results provide evidence that TGF-β1 cooperates with HBx to promote the malignant transformation of HPCs through a JNK/c-Jun/miR-199a-3p-dependent pathway. This may open new avenues for therapeutic interventions targeting the malignant transformation of HPCs in treating liver cancer.
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Affiliation(s)
- Ke-Shuai Dong
- Hepatic Surgery Center, Department of Hepatic Surgery, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China.,Department of Hepatobiliary and Laparoscopic Surgery, Renmin Hospital, Wuhan University, Hubei Key Laboratory of Digestive System Disease, Wuhan, China
| | - Yan Chen
- Department of General Surgery, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Guang Yang
- Hepatic Surgery Center, Department of Hepatic Surgery, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Zhi-Bin Liao
- Hepatic Surgery Center, Department of Hepatic Surgery, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Hong-Wei Zhang
- Hepatic Surgery Center, Department of Hepatic Surgery, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Hui-Fang Liang
- Hepatic Surgery Center, Department of Hepatic Surgery, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Xiao-Ping Chen
- Hepatic Surgery Center, Department of Hepatic Surgery, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Han-Hua Dong
- Hepatic Surgery Center, Department of Hepatic Surgery, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China.
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5
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He B, Peng F, Li W, Jiang Y. Interaction of lncRNA-MALAT1 and miR-124 regulates HBx-induced cancer stem cell properties in HepG2 through PI3K/Akt signaling. J Cell Biochem 2018; 120:2908-2918. [PMID: 30500989 DOI: 10.1002/jcb.26823] [Citation(s) in RCA: 41] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2017] [Accepted: 02/28/2018] [Indexed: 12/15/2022]
Abstract
BACKGROUND Hepatitis B virus X protein (HBx) plays a crucial role in initiating and promoting HBV-induced hepatocellular carcinoma (HCC) development. Reports indicated that HBx promotes cancer stem cell (CSC) generation, which may be associated with HBV-related HCC. Noncoding RNA miR-124 and long noncoding RNA (lncRNA)-metastasis-associated lung adenocarcinoma transcript 1 (MALAT1) were considered to be involved deeply in the progress of HBx-related HCC. Hence, the underlying mechanism of miR-124 and lncRNA-MALAT1 in regulating HBx-promoted CSC needs to be studied. MATERIALS AND METHODS In present study, HepG2-X cell line was induced by transfect HBx into HepG2 cells. Overexpressing of miR-124 or silencing of lncRNA-MALAT1 was completed by transfecting miR-124 mimic or shMALAT1 into HepG2-X cells. HBx-induced CSC properties and tumorigenic potential of HepG2 cells were determined by detecting CSC marker expression, colony formation assay, and xenograft tumorigenesis. The mechanism of HBx-induced CSC properties was explored by PI3K/Akt inhibitor. Interaction of miR-124 and lncRNA-MALAT1 was detected by luciferase reporter assay. RESULTS HBx promoted CSC properties through upregulating stemness markers and reprogramming proteins, and contributed to tumorigenicity of HepG2-X cells both in vivo and in vitro. Inhibition of Akt activation blocked the HBx-stimulated reprogramming proteins and stemness markers. HBx upregulated lncRNA-MALAT1 expression while downregulating miR-124 expression in HepG2-X cells. miR-124 interacts with lncRNA-MALAT1 by direct targeting. Overexpression of miR-124 or silencing of lncRNA-MALAT1 both blocked HBx-induced CSC generation, stemness-related factor activation and tumorigenicity via PI3K/Akt signaling. CONCLUSION Our results demonstrated that miR-124 interact with lncRNA-MALAT1 and involve in regulating HBx-induced CSC properties via PI3K/Akt signaling.
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Affiliation(s)
- Bo He
- Department of Infectious Diseases, Second Xiangya Hospital, Central South University, Changsha, People's Republic of China
| | - Feng Peng
- Department of Infectious Diseases, Second Xiangya Hospital, Central South University, Changsha, People's Republic of China
| | - Wei Li
- Department of Infectious Diseases, Second Xiangya Hospital, Central South University, Changsha, People's Republic of China
| | - Yongfang Jiang
- Department of Infectious Diseases, Second Xiangya Hospital, Central South University, Changsha, People's Republic of China
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6
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Yin X, Sun S, Zhao J, Yang J, Lei X, Xu C, Li K. Rs4705342 polymorphism is involved in the tumorigenesis of HBV positive HCC by altering the binding affinity of HBV induced NF‐kB with the promoter region of microRNA‐143. J Cell Biochem 2018; 119:5233-5242. [PMID: 29236306 DOI: 10.1002/jcb.26581] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2017] [Accepted: 12/04/2017] [Indexed: 01/05/2023]
Affiliation(s)
- Xiuli Yin
- Department of Internal MedicineShandong Rongjun HospitalJinanP.R. China
| | - Shiying Sun
- Department of General SurgeryShandong Rongjun HospitalJinanP.R. China
| | - Junyan Zhao
- Department of GastroenterologyShandong Qianfoshan Hospital Affiliated to Shandong UniversityJinanP.R. China
| | - Jing Yang
- Department of GastroenterologyShandong Qianfoshan Hospital Affiliated to Shandong UniversityJinanP.R. China
| | - Xiaofei Lei
- Department of GastroenterologyShandong Qianfoshan Hospital Affiliated to Shandong UniversityJinanP.R. China
| | - Changqing Xu
- Department of GastroenterologyShandong Qianfoshan Hospital Affiliated to Shandong UniversityJinanP.R. China
| | - Kun Li
- Department of GastroenterologyShandong Qianfoshan Hospital Affiliated to Shandong UniversityJinanP.R. China
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7
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Wang MD, Wu H, Huang S, Zhang HL, Qin CJ, Zhao LH, Fu GB, Zhou X, Wang XM, Tang L, Wen W, Yang W, Tang SH, Cao D, Guo LN, Zeng M, Wu MC, Yan HX, Wang HY. HBx regulates fatty acid oxidation to promote hepatocellular carcinoma survival during metabolic stress. Oncotarget 2017; 7:6711-26. [PMID: 26744319 PMCID: PMC4872744 DOI: 10.18632/oncotarget.6817] [Citation(s) in RCA: 55] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2015] [Accepted: 12/29/2015] [Indexed: 02/06/2023] Open
Abstract
Due to a high rate of nutrient consumption and inadequate vascularization, hepatocellular carcinoma (HCC) cells constantly undergo metabolic stress during tumor development. Hepatitis B virus (HBV) X protein (HBx) has been implicated in the pathogenesis of HBV-induced HCC. In this study, we investigated the functional roles of HBx in HCC adaptation to metabolic stress. Up-regulation of HBx increased the intracellular ATP and NADPH generation, and induced the resistance to glucose deprivation, whereas depletion of HBx via siRNA abolished these effects and conferred HCC cells sensitive to glucose restriction. Though HBx did not affect the glycolysis and oxidative phosphorylation capacity of HCC cells under normal culture conditions, it facilitated fatty acid oxidation (FAO) in the absence of glucose, which maintained NADPH and ATP levels. Further investigation showed that HBx expression, under glucose deprivation, stimulated phosphorylation of AMP-activated protein kinase (AMPK) and acetyl-CoA carboxylase (ACC) via a calcium/CaMKK-dependent pathway, which was required for the activation of FAO. Conversely, inhibition of FAO by etomoxir (ETO) restored the sensitivity of HBx-expressing cells to glucose deficiency in vitro and retarded xenograft tumor formation in vivo. Finally, HBx-induced activation of the AMPK and FAO pathways were also observed in xenograft tumors and HBV-associated HCC specimens. Our data suggest that HBx plays a key role in the maintenance of redox and energy homeostasis by activating FAO, which is critical for HCC cell survival under conditions of metabolic stress and might be exploited for therapeutic benefit.
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Affiliation(s)
- Ming-Da Wang
- International Cooperation Laboratory on Signal Transduction, Eastern Hepatobiliary Surgery Institute, The Second Military Medical University, Shanghai 200438, P.R. China.,National Center for Liver Cancer Research, Shanghai 201805, P.R. China
| | - Han Wu
- International Cooperation Laboratory on Signal Transduction, Eastern Hepatobiliary Surgery Institute, The Second Military Medical University, Shanghai 200438, P.R. China
| | - Shuai Huang
- International Cooperation Laboratory on Signal Transduction, Eastern Hepatobiliary Surgery Institute, The Second Military Medical University, Shanghai 200438, P.R. China
| | - Hui-Lu Zhang
- International Cooperation Laboratory on Signal Transduction, Eastern Hepatobiliary Surgery Institute, The Second Military Medical University, Shanghai 200438, P.R. China
| | - Chen-Jie Qin
- International Cooperation Laboratory on Signal Transduction, Eastern Hepatobiliary Surgery Institute, The Second Military Medical University, Shanghai 200438, P.R. China.,National Center for Liver Cancer Research, Shanghai 201805, P.R. China
| | - Ling-Hao Zhao
- International Cooperation Laboratory on Signal Transduction, Eastern Hepatobiliary Surgery Institute, The Second Military Medical University, Shanghai 200438, P.R. China.,Department of Surgery, Eastern Hepatobiliary Surgery Hospital, Second Military Medical University, Shanghai 200433, P.R. China
| | - Gong-Bo Fu
- International Cooperation Laboratory on Signal Transduction, Eastern Hepatobiliary Surgery Institute, The Second Military Medical University, Shanghai 200438, P.R. China.,National Center for Liver Cancer Research, Shanghai 201805, P.R. China
| | - Xu Zhou
- International Cooperation Laboratory on Signal Transduction, Eastern Hepatobiliary Surgery Institute, The Second Military Medical University, Shanghai 200438, P.R. China.,National Center for Liver Cancer Research, Shanghai 201805, P.R. China
| | - Xian-Ming Wang
- International Cooperation Laboratory on Signal Transduction, Eastern Hepatobiliary Surgery Institute, The Second Military Medical University, Shanghai 200438, P.R. China.,National Center for Liver Cancer Research, Shanghai 201805, P.R. China
| | - Liang Tang
- International Cooperation Laboratory on Signal Transduction, Eastern Hepatobiliary Surgery Institute, The Second Military Medical University, Shanghai 200438, P.R. China
| | - Wen Wen
- International Cooperation Laboratory on Signal Transduction, Eastern Hepatobiliary Surgery Institute, The Second Military Medical University, Shanghai 200438, P.R. China.,National Center for Liver Cancer Research, Shanghai 201805, P.R. China
| | - Wen Yang
- International Cooperation Laboratory on Signal Transduction, Eastern Hepatobiliary Surgery Institute, The Second Military Medical University, Shanghai 200438, P.R. China.,National Center for Liver Cancer Research, Shanghai 201805, P.R. China
| | - Shan-Hua Tang
- International Cooperation Laboratory on Signal Transduction, Eastern Hepatobiliary Surgery Institute, The Second Military Medical University, Shanghai 200438, P.R. China.,National Center for Liver Cancer Research, Shanghai 201805, P.R. China
| | - Dan Cao
- International Cooperation Laboratory on Signal Transduction, Eastern Hepatobiliary Surgery Institute, The Second Military Medical University, Shanghai 200438, P.R. China.,National Center for Liver Cancer Research, Shanghai 201805, P.R. China
| | - Lin-Na Guo
- International Cooperation Laboratory on Signal Transduction, Eastern Hepatobiliary Surgery Institute, The Second Military Medical University, Shanghai 200438, P.R. China.,National Center for Liver Cancer Research, Shanghai 201805, P.R. China
| | - Min Zeng
- International Cooperation Laboratory on Signal Transduction, Eastern Hepatobiliary Surgery Institute, The Second Military Medical University, Shanghai 200438, P.R. China.,National Center for Liver Cancer Research, Shanghai 201805, P.R. China
| | - Meng-Chao Wu
- Department of Surgery, Eastern Hepatobiliary Surgery Hospital, Second Military Medical University, Shanghai 200433, P.R. China
| | - He-Xin Yan
- International Cooperation Laboratory on Signal Transduction, Eastern Hepatobiliary Surgery Institute, The Second Military Medical University, Shanghai 200438, P.R. China.,National Center for Liver Cancer Research, Shanghai 201805, P.R. China
| | - Hong-Yang Wang
- International Cooperation Laboratory on Signal Transduction, Eastern Hepatobiliary Surgery Institute, The Second Military Medical University, Shanghai 200438, P.R. China.,National Center for Liver Cancer Research, Shanghai 201805, P.R. China.,State Key Laboratory of Oncogenes and Related Genes, Shanghai Cancer Institute, Renji Hospital, Shanghai Jiao Tong University, Shanghai 200032, P.R. China
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Chen X, Zhang L, Zheng S, Zhang T, Li M, Zhang X, Zeng Z, McCrae MA, Zhao J, Zhuang H, Lu F. Hepatitis B Virus X Protein Stabilizes Cyclin D1 and Increases Cyclin D1 Nuclear Accumulation through ERK-Mediated Inactivation of GSK-3β. Cancer Prev Res (Phila) 2015; 8:455-63. [PMID: 25712050 DOI: 10.1158/1940-6207.capr-14-0384] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2014] [Accepted: 02/09/2015] [Indexed: 01/13/2023]
Abstract
The Hepatitis B virus X protein (HBx) contributes centrally to the pathogenesis of hepatocellular carcinoma (HCC). It has been suggested that the transcriptional activation of cyclin D1 by HBx is implicated in the development of HCC. However, numerous studies have shown that overexpression of cyclin D1 alone is not sufficient to drive oncogenic transformation. Herein, we investigated whether HBx can stabilize cyclin D1 and induce cyclin D1 protein nuclear accumulation, and thereby accelerate hepatocarcinogenesis. The effects of HBx on cyclin D1 stabilization were assessed in cell-based transfection, Western blot, immunoprecipitation, immunocytofluorescence staining, and flow-cytometric assays. The results demonstrated that ectopic expression of HBx in HCC cells could extend the half-life of cyclin D1 protein from 40-60 minutes to 80-110 minutes. HBx stabilized cyclin D1 primarily in the S phase of the cell cycle, in a manner dependent on the inactivation of GSK-3β, which was mediated by ERK activation. HBx also prompted the nuclear accumulation of cyclin D1, and cotransfection of the constitutively active mutant of GSK-3β along with HBx could reverse the nuclear accumulation and subsequent cell proliferation induced by HBx. Further, a positive correlation between HBx and nuclear cyclin D1 level was established in HCC specimens detected by an immunohistochemical assay. Taken together, our results indicated that HBx could stabilize and increase cyclin D1 nuclear accumulation through ERK-mediated inactivation of GSK-3β. This HBx-induced cyclin D1 upregulation might play an important role in HCC development and progression.
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Affiliation(s)
- Xiangmei Chen
- Department of Microbiology and Infectious Disease Center, School of Basic Medical Science, Peking University Health Science Center, Beijing, P.R. China
| | - Ling Zhang
- Department of Hepatobiliary Surgery, Henan Cancer Hospital, Zhengzhou, P.R. China
| | - Sujun Zheng
- Beijing YouAn hospital, Capital Medical University, Beijing, P.R. China
| | - Ting Zhang
- Department of Microbiology and Infectious Disease Center, School of Basic Medical Science, Peking University Health Science Center, Beijing, P.R. China
| | - Meng Li
- Department of Microbiology and Infectious Disease Center, School of Basic Medical Science, Peking University Health Science Center, Beijing, P.R. China
| | - Xiaolei Zhang
- Department of Microbiology and Infectious Disease Center, School of Basic Medical Science, Peking University Health Science Center, Beijing, P.R. China
| | - Zhenzhen Zeng
- Department of Microbiology and Infectious Disease Center, School of Basic Medical Science, Peking University Health Science Center, Beijing, P.R. China
| | | | - Jingmin Zhao
- Department of Pathology, Institute of Infectious Diseases, Beijing 302 Hospital, Beijing, P.R. China
| | - Hui Zhuang
- Department of Microbiology and Infectious Disease Center, School of Basic Medical Science, Peking University Health Science Center, Beijing, P.R. China
| | - Fengmin Lu
- Department of Microbiology and Infectious Disease Center, School of Basic Medical Science, Peking University Health Science Center, Beijing, P.R. China.
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9
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Tang S, Hu W, Hu J, Wu S, Li J, Luo Y, Cao M, Zhou H, Jiang X. Hepatitis B virus X protein promotes P3 transcript expression of the insulin-like growth factor 2 gene via inducing hypomethylation of P3 promoter in hepatocellular carcinoma. Liver Int 2015; 35:608-19. [PMID: 24423280 DOI: 10.1111/liv.12469] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/05/2013] [Accepted: 01/08/2014] [Indexed: 12/11/2022]
Abstract
BACKGROUND & AIMS Hepatitis B virus (HBV) X protein (HBx) contributes to hepatocarcinogenesis. The overexpression of transcripts from P3 and P4 promoters of the insulin-like growth factor 2 (IGF2) gene is observed in hepatocellular carcinoma (HCC). Here, we aimed to explore the involvement of HBx in P3-driven mRNA overexpression and underlying epigenetic mechanism. METHODS P3 mRNA, P3 methylation status, HBx mRNA and HBx protein were analysed in human HCC samples with and without HBV infection using quantitative RT-PCR, bisulphite sequencing and Western blotting. The effects of HBx on P3 mRNA expression, and P3 transcriptional activity and methylation were further evaluated in HCC cell lines. RESULTS P3 mRNA level was higher and P3 methylation level was lower in HBV-positive HCC specimens compared with those of HBV-negative HCC specimens. P3 transcript abundance was positively correlated with HBx expression and negatively correlated with P3 methylation in HCC specimens. The stable expression of HBx upregulated P3 mRNA expression and reduced P3 methylation level in HepG2-HBx cells. The transient expression of HBx stimulated P3 promoter activity and decreased P3 methylation level of P3 promoter-luciferase construct in a dose-dependent manner in HepG2 and Huh-7 cells. Furthermore, HBx mRNA expression was found to be independent predictive factors for both shorter disease-free survival time and shorter overall survival time of HCC patients. CONCLUSION HBx may promote IGF2-P3 transcript expression by inducing hypomethylation of P3 promoter and may be associated with an inferior clinical outcome of HBV-related HCC patients. This study provides useful information for understanding the mechanism of HBx-mediated HCC.
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Affiliation(s)
- Shaohui Tang
- Department of Gastroenterology, The First Affiliated Hospital, Jinan University, Guangzhou, China
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10
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Robinson KM, Dunning Hotopp JC. Mobile elements and viral integrations prompt considerations for bacterial DNA integration as a novel carcinogen. Cancer Lett 2014; 352:137-44. [PMID: 24956175 DOI: 10.1016/j.canlet.2014.05.021] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2014] [Revised: 04/30/2014] [Accepted: 05/01/2014] [Indexed: 12/11/2022]
Abstract
Insertional mutagenesis has been repeatedly demonstrated in cancer genomes and has a role in oncogenesis. Mobile genetic elements can induce cancer development by random insertion into cancer related genes or by inducing translocations. L1s are typically implicated in cancers of an epithelial cell origin, while Alu elements have been implicated in leukemia as well as epithelial cell cancers. Likewise, viral infections have a significant role in cancer development predominantly through integration into the human genome and mutating or deregulating cancer related genes. Human papilloma virus is the best-known example of viral integrations contributing to carcinogenesis. However, hepatitis B virus, Epstein-Barr virus, and Merkel cell polyomavirus also integrate into the human genome and disrupt cancer related genes. Thus far, the role of microbes in cancer has primarily been attributed to mutations induced through chronic inflammation or toxins, as is the case with Helicobacter pylori and enterotoxigenic Bacteroides fragilis. We hypothesize that like mobile elements and viral DNA, bacterial and parasitic DNA may also integrate into the human somatic genome and be oncogenic. Until recently it was believed that bacterial DNA could not integrate into the human genome, but new evidence demonstrates that bacterial insertional mutagenesis may occur in cancer cells. Although this work does not show causation between bacterial insertions and cancer, it prompts more research in this area. Promising new sequencing technologies may reduce the risk of artifactual chimeric sequences, thus diminishing some of the challenges of identifying novel insertions in the somatic human genome.
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Affiliation(s)
- Kelly M Robinson
- Institute for Genome Sciences, University of Maryland School of Medicine, Baltimore, MD, USA
| | - Julie C Dunning Hotopp
- Institute for Genome Sciences, University of Maryland School of Medicine, Baltimore, MD, USA; Department of Microbiology and Immunology, University of Maryland School of Medicine, Baltimore, MD, USA; Greenebaum Cancer Center, University of Maryland School of Medicine, Baltimore, MD, USA.
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11
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Lun YZ, Cheng J, Chi Q, Wang XL, Gao M, Sun LDA. Transactivation of proto-oncogene c-Myc by hepatitis B virus transactivator MHBs t167.. Oncol Lett 2014; 8:803-808. [PMID: 25009657 PMCID: PMC4081436 DOI: 10.3892/ol.2014.2190] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2013] [Accepted: 04/29/2014] [Indexed: 01/04/2023] Open
Abstract
C-terminally truncated hepatitis B virus (HBV) middle size surface proteins (MHBst) has been shown to be a transcriptional activator and may be relevant to hepatocarcinogenesis by transactivating gene expression. In the present study, a pcDNA3.1(-)-MHBst167 vector coding for MHBst truncated at amino acid 167 (MHBst167) was constructed and transfected into the HepG2 hepatoma cell line. mRNA and protein expression of MHBst167 in the cells was detected by reverse transcription-polymerase chain reaction (RT-PCR) and western blot analysis. A cDNA library of genes transactivated by the truncated protein in HepG2 cells was made in pGEM-T Easy using suppression subtractive hybridization. The cDNAs were sequenced and analyzed with BLAST searching against the sequences in GenBank. The results showed that certain sequences, such as that of human proto-oncogene c-Myc, may be involved in tumor development. An expression vector pCAT3/c-Myc containing the chloramphenicol acetyltransferase (CAT) gene under the control of a c-Myc promoter was generated, and the transcriptional transactivating effect of MHBst167 on the c-Myc promoter was investigated by RT-PCR and western blotting. MHBst167 was found to upregulate the transcriptional activity of the promoter, as well as transcription and translation of c-Myc. MHBst167 was also shown to transactivate SV40 immediate early promoter, and transcriptionally transactivate the expression of human c-Myc. These findings provide new directions for studying the biological functions of MHBst167, and for a better understanding of the tumor development mechanisms of HBV infection.
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Affiliation(s)
- Yong-Zhi Lun
- Liaoning Provincial University Key Laboratory of Biophysics, College of Medicine, Dalian University, Dalian, Liaoning 116622, P.R. China
| | - Jun Cheng
- Institute of Infectious Diseases, Beijing Ditan Hospital, Capital Medical University, Beijing 100015, P.R. China
| | - Qing Chi
- Liaoning Provincial University Key Laboratory of Biophysics, College of Medicine, Dalian University, Dalian, Liaoning 116622, P.R. China
| | - Xue-Lei Wang
- Liaoning Provincial University Key Laboratory of Biophysics, College of Medicine, Dalian University, Dalian, Liaoning 116622, P.R. China
| | - Meng Gao
- Liaoning Provincial University Key Laboratory of Biophysics, College of Medicine, Dalian University, Dalian, Liaoning 116622, P.R. China
| | - Li-DA Sun
- Liaoning Provincial University Key Laboratory of Biophysics, College of Medicine, Dalian University, Dalian, Liaoning 116622, P.R. China
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12
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Feitelson MA, Bonamassa B, Arzumanyan A. The roles of hepatitis B virus-encoded X protein in virus replication and the pathogenesis of chronic liver disease. Expert Opin Ther Targets 2014; 18:293-306. [PMID: 24387282 DOI: 10.1517/14728222.2014.867947] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
INTRODUCTION Hepatitis B virus (HBV) is a major cause of chronic liver disease (CLD) and hepatocellular carcinoma (HCC) worldwide. More than 350 million people are at risk for HCC, and with few treatment options available, therapeutic approaches to targets other than the virus polymerase will be needed. This review suggests that the HBV-encoded X protein, HBx, would be an outstanding target because it contributes to the biology and pathogenesis of HBV in three fundamental ways. AREAS COVERED First, HBx is a trans-activating protein that stimulates virus gene expression and replication, thereby promoting the development and persistence of the carrier state. Second, HBx partially blocks the development of immune responses that would otherwise clear the virus, and protects infected hepatocytes from immune-mediated destruction. Thus, HBx contributes to the development of CLD without virus clearance. Third, HBx alters patterns of host gene expression that make possible the emergence of HCC. The selected literature cited is from the National Library of Medicine (Pubmed and Medline). EXPERT OPINION Understanding the mechanisms, whereby HBx supports virus replication and promotes pathogenesis, suggests that HBx will be an important therapeutic target against both virus replication and CLD aimed at the chemoprevention of HCC.
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Affiliation(s)
- Mark A Feitelson
- Temple University, College of Science and Technology, Department of Biology , Room 409 BioLife Science Building, 1900 N. 12th Street, Philadelphia, PA 19122 , USA +1 215 204 8434 ; +1 215 204 8359 ;
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13
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Gai X, Zhao P, Pan Y, Shan H, Yue X, Du J, Zhang Z, Liu P, Ma H, Guo M, Yang X, Sun W, Gao L, Ma C, Liang X. Hepatitis B virus core protein enhances human telomerase reverse transcriptase expression and hepatocellular carcinoma cell proliferation in a c-Ets2-dependent manner. Int J Biochem Cell Biol 2013; 45:1174-85. [DOI: 10.1016/j.biocel.2013.03.015] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2012] [Revised: 03/10/2013] [Accepted: 03/18/2013] [Indexed: 02/07/2023]
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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: 6.5] [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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Arzumanyan A, Friedman T, Ng IOL, Clayton MM, Lian Z, Feitelson MA. Does the hepatitis B antigen HBx promote the appearance of liver cancer stem cells? Cancer Res 2011; 71:3701-8. [PMID: 21464043 DOI: 10.1158/0008-5472.can-10-3951] [Citation(s) in RCA: 86] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Hepatitis B virus (HBV) is a major etiologic agent of chronic liver disease and hepatocellular carcinoma (HCC). HBV-encoded X antigen, HBx, and pathways implicated in the self-renewal of stem cells contribute to HCC, but it is not clear whether HBx expression promotes "stemness." Thus, experiments were designed to test the hypothesis that HBx triggers malignant transformation by promoting properties that are characteristic of cancer stem cells (CSC). To test this hypothesis, HepG2 cells were stably transduced with HBx and then assayed for phenotypic and molecular characteristics of "stemness." The relationship between HBx and "stemness"-associated markers was also evaluated by immunohistochemical staining of liver and tumor tissue sections from HBV-infected patients. The results showed that Oct-4, Nanog, Klf-4, β-catenin, and epithelial cell adhesion molecule (EpCAM) were activated by HBx in vitro and in vivo. EpCAM was detected in the nuclei of human HCC cells from infected patients. HBx promotes "stemness" by activating β-catenin and epigenetic upregulation of miR-181, both of which target EpCAM. HBx expression was also associated with depressed levels of E-cadherin. Moreover, HBx stimulated cell migration, growth in soft agar, and spheroid formation. This work is the first to propose that HBV promotes "stemness" in the pathogenesis of HCC. HBx-associated upregulated expression of multiple "stemness" markers supports the hypothesis that HBx contributes to hepatocarcinogenesis, at least in part, by promoting changes in gene expression that are characteristics of CSCs.
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Affiliation(s)
- Alla Arzumanyan
- Department of Biology, Sbarro Health Research Organization, College of Science and Technology, Temple University, Philadelphia, Pennsylvania 19122, USA.
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16
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Liu J, Ahiekpor A, Li L, Li X, Arbuthnot P, Kew M, Feitelson MA. Increased expression of ErbB-2 in liver is associated with hepatitis B x antigen and shorter survival in patients with liver cancer. Int J Cancer 2009; 125:1894-901. [PMID: 19610068 DOI: 10.1002/ijc.24580] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Hepatitis B x antigen, or HBxAg, contributes importantly to the pathogenesis of hepatocellular carcinoma (HCC). Given that HBxAg constitutively activates beta-catenin and that upregulated ErbB-2 promotes beta-catenin signaling in other tumor types, experiments were designed to ask whether HBxAg was associated with upregulated expression of ErbB-2. When HBxAg positive and negative HepG2 cells were subjected to proteomics analysis, ErbB-2 was shown to be upregulated in HepG2X but not control cells. ErbB-2 was also strongly upregulated in HB infected liver, and weakly in some HCC nodules, where it correlated with HBxAg expression. Among tumor bearing patients, strong ErbB-2 staining in the liver was associated with dysplasia, and a shorter survival after tumor diagnosis. This implies that elevated ErbB-2 is an early marker of HCC. Treatment of HepG2X cells with ErbB-2 specific siRNA not only reduced ErbB-2 expression, but also reduced the expression of beta-catenin, suggesting that ErbB-2 contributed to the stabilization of beta-catenin. ErbB-2 specific siRNA also partially blocked the ability of HBxAg to promote DNA synthesis and growth of HepG2 cells. These results suggest that ErbB-2/beta-catenin up-regulation contributes importantly to the mechanism of HBxAg mediated hepatocellular growth.
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Affiliation(s)
- Jie Liu
- Department of Pathology, Anatomy and Cell Biology, Thomas Jefferson University, Philadelphia, PA, USA
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Ely A, Naidoo T, Arbuthnot P. Efficient silencing of gene expression with modular trimeric Pol II expression cassettes comprising microRNA shuttles. Nucleic Acids Res 2009; 37:e91. [PMID: 19474340 PMCID: PMC2715259 DOI: 10.1093/nar/gkp446] [Citation(s) in RCA: 57] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
Expressed polycistronic microRNA (miR) cassettes have useful properties that can be utilized for RNA interference (RNAi)-based gene silencing. To advance their application we generated modular trimeric anti-hepatitis B virus (HBV) Pol II cassettes encoding primary (pri)-miR-31-derived shuttles that target three different viral genome sites. A panel of six expression cassettes, comprising each of the possible ordering combinations of the pri-miR-31 shuttles, was initially tested. Effective silencing of individual target sequences was achieved in transfected cells and transcribed pri-miR trimers generated intended guide strands. There was, however, variation in processing and silencing by each of the shuttles. In some cases the monomers’ position within the trimers influenced processing and this correlated with target silencing. Compromised efficacy could be compensated by substituting the pri-miR-31 backbone with a pri-miR-30a scaffold. Inhibition of HBV replication was achieved in vivo, and in cell culture without disruption of endogenous miR function or induction of the interferon response. A mutant HBV target sequence, with changes in one of the guide cognates, was also silenced by the trimeric cassettes. The modular nature of the cassettes together with compatibility with expression from Pol II promoters should be advantageous for gene silencing applications requiring simultaneous targeting of different sites.
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Affiliation(s)
- Abdullah Ely
- Antiviral Gene Therapy Research Unit, Department of Molecular Medicine and Haematology, University of the Witwatersrand Medical School, Private Bag 3 WITS 2050, South Africa
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Zhang WY, Xu FQ, Shan CL, Xiang R, Ye LH, Zhang XD. Gene expression profiles of human liver cells mediated by hepatitis B virus X protein. Acta Pharmacol Sin 2009; 30:424-34. [PMID: 19343061 PMCID: PMC4002275 DOI: 10.1038/aps.2009.22] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2008] [Accepted: 02/12/2009] [Indexed: 12/16/2022] Open
Abstract
AIM To demonstrate the gene expression profiles mediated by hepatitis B virus X protein (HBx), we characterized the molecular features of pathogenesis associated with HBx in a human liver cell model. METHODS We examined gene expression profiles in L-O2-X cells, an engineered L-O2 cell line that constitutively expresses HBx, relative to L-O2 cells using an Agilent 22 K human 70-mer oligonucleotide microarray representing more than 21,329 unique, well-characterized Homo sapiens genes. Western blot analysis and RNA interference (RNAi) targeting HBx mRNA validated the overexpression of proliferating cell nuclear antigen (PCNA) and Bcl-2 in L-O2-X cells. Meanwhile, the BrdU incorporation assay was used to test cell proliferation mediated by upregulated cyclooxygenase-2 (COX-2). RESULTS The microarray showed that the expression levels of 152 genes were remarkably altered; 82 of the genes were upregulated and 70 genes were downregulated in L-O2-X cells. The altered genes were associated with signal transduction pathways, cell cycle, metastasis, transcriptional regulation, immune response, metabolism, and other processes. PCNA and Bcl-2 were upregulated in L-O2-X cells. Furthermore, we found that COX-2 upregulation in L-O2-X cells enhanced proliferation using the BrdU incorporation assay, whereas indomethacin (an inhibitor of COX-2) abolished the promotion. CONCLUSION Our findings provide new evidence that HBx is able to regulate many genes that may be involved in the carcinogenesis. These regulated genes mediated by HBx may serve as molecular targets for the prevention and treatment of hepatocellular carcinoma.
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Affiliation(s)
- Wei-ying Zhang
- Department of Cancer Research, Key Laboratory of Molecular Microbiology and Technology of Ministry of Education, Institute for Molecular Biology, College of Life Sciences, Nankai University, Tianjin 300071, China
| | - Fu-qing Xu
- Department of Cancer Research, Key Laboratory of Molecular Microbiology and Technology of Ministry of Education, Institute for Molecular Biology, College of Life Sciences, Nankai University, Tianjin 300071, China
| | - Chang-liang Shan
- Department of Cancer Research, Key Laboratory of Molecular Microbiology and Technology of Ministry of Education, Institute for Molecular Biology, College of Life Sciences, Nankai University, Tianjin 300071, China
| | - Rong Xiang
- School of Medicine, Nankai University, Tianjin 300071, China
| | - Li-hong Ye
- Department of Biochemistry, College of Life Sciences, Nankai University, Tianjin 300071, China
| | - Xiao-dong Zhang
- Department of Cancer Research, Key Laboratory of Molecular Microbiology and Technology of Ministry of Education, Institute for Molecular Biology, College of Life Sciences, Nankai University, Tianjin 300071, China
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19
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Putative roles of hepatitis B x antigen in the pathogenesis of chronic liver disease. Cancer Lett 2009; 286:69-79. [PMID: 19201080 DOI: 10.1016/j.canlet.2008.12.010] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2008] [Revised: 11/18/2008] [Accepted: 12/02/2008] [Indexed: 12/18/2022]
Abstract
Under most circumstances, hepatitis B virus (HBV) is noncytopathic. However, hepatocellular regeneration that accompanies each bout of hepatitis appears to be associated with increased integration of HBV DNA fragments expressing the virus encoded hepatitis B x antigen (HBxAg). Intrahepatic HBxAg staining correlates with the intensity and progression of chronic liver disease (CLD), and additional work has shown that HBxAg blocks immune mediated killing by Fas and by tumor necrosis factor alpha (TNFalpha). This is not only associated with the blockage of caspase activities by HBxAg, but also by the constitutive stimulation of hepatoprotective pathways, such as nuclear factor kappa B (NF-kappaB), phosphoinositol 3-kinase (PI3K), and beta-catenin (beta-catenin). HBxAg also appears to promote fibrogenesis, by stimulating the production of fibronectin. HBxAg also stimulates the production and activity of transforming growth factor beta1 (TGFbeta1) by several mechanisms, thereby promoting the profibrogenic and tumorigenic properties of this important cytokine. In addition, HBxAg appears to remodel the extracellular matrix (ECM) by altering the expression of several matrix metalloproteinases (MMPs), which may promote tumor metastasis. Hence, HBxAg appears to promote chronic infection by preventing immune mediated apoptosis of infected hepatocytes, by promoting the establishment and persistence of fibrosis and cirrhosis preceding the development of HCC, and by promoting the remodeling of EMC during tumor progression.
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20
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Feitelson MA, Reis HMGPV, Pan J, Clayton M, Sun B, Satiroglu-Tufan NL, Lian Z. HBV X protein: elucidating a role in oncogenesis. Future Virol 2008. [DOI: 10.2217/17460794.3.5.455] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Chronic HBV infection is associated with the development of hepatocellular carcinoma (HCC). HBV contributes to tumorigenesis by encoding hepatitis B x antigen (HBxAg), which is a trans-regulatory protein that appears to contribute to HCC by altering patterns of host gene expression. In this review, recent data is presented that outlines some of the putative mechanisms whereby HBxAg contributes to HCC. With the development of animal models of HBxAg-mediated HCC, the relevance and temporal order of putative steps in this process can now be dissected to elucidate what is rate limiting and when. This will have a profound impact on the design of novel and specific therapeutics for HCC.
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Affiliation(s)
- Mark A Feitelson
- Department of Biology, College of Science & Technology, Temple University, PA 19122, USA. and, Center for Biotechnology, College of Science & Technology, Temple University, PA 19122, USA
| | - Helena MGPV Reis
- MIT Portugal Program, Av. Antonio Jose de Almeida, 12 1000–043 Lisboa, Portugal
| | - Jingbo Pan
- Department of Pathology, Anatomy & Cell Biology, Thomas Jefferson University, PA 19107, USA
| | - Marcy Clayton
- Department of Biology, College of Science & Technology, Temple University, PA 19122, USA
| | - Bill Sun
- Department of Biology, College of Science & Technology, Temple University, PA 19122, USA
| | - N Lale Satiroglu-Tufan
- Department of Medical Biology, Pamukkale University School of Medicine, Kinikli Kampusu Morfoloji Binasi, 20020 Denizli, Turkey
| | - Zhaorui Lian
- Department of Biology, College of Science & Technology, Temple University, PA 19122, USA
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Tao X, Shen D, Ren H, Zhang X, Zhang D, Gu B, Ye J. The role of hepatitis B virus x gene in development of primary hepatocellular carcinoma. SCIENCE IN CHINA. SERIES C, LIFE SCIENCES 2008; 43:293-301. [PMID: 18726385 DOI: 10.1007/bf02879289] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/17/1999] [Indexed: 12/01/2022]
Abstract
Primary hepatocellular carcinoma (HCC) is one of the most common cancers occurring in human, and there is strong epidemiological evidence suggesting that persistent hepatitis B virus (HBV) infection is the most important risk factor for its development.HBx gene was found to be a transactivator recently. Its continuous expression in hepatocytes may transactivate cellular genes which can play a certain role in development of HCC. TheHBx gene fragment was used to construct a recombinant eukaryotic expression vector pCEP4 and introduced into HepG2 cells. The effect ofHBx gene on HCC cells growth and its molecular mechanism in HCC cells regulation were investigated.
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Affiliation(s)
- X Tao
- The first Affiliated Hospital, Chongqing University of Medical Sciences, 400016, Chongqing, China,
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22
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Kim SY, Kim JC, Kim JK, Kim HJ, Lee HM, Choi MS, Maeng PJ, Ahn JK. Hepatitis B virus X protein enhances NFκB activity through cooperating with VBP1. BMB Rep 2008; 41:158-63. [DOI: 10.5483/bmbrep.2008.41.2.158] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
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Abstract
This article reviews the molecular biology of the hepatitis B virus in an effort to explain its natural history from a molecular perspective. The life cycle of the virus, with special attention to virus replication, polypeptide production, and morphogenesis, is described. The way in which these steps may influence the natural history of viral pathogenesis, as well as the effectiveness of interventions, receives special consideration.
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Lian Z, Liu J, Wu M, Wang HY, Arbuthnot P, Kew M, Feitelson MA. Hepatitis B x antigen up-regulates vascular endothelial growth factor receptor 3 in hepatocarcinogenesis. Hepatology 2007; 45:1390-9. [PMID: 17539024 DOI: 10.1002/hep.21610] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Hepatitis B x antigen (HBxAg) is a trans-activating protein that contributes to liver cancer, in part, by altering the expression of cellular genes. However, few natural effectors of HBxAg have been identified. Hence, HBxAg positive and negative HepG2 cells were prepared and analyzed by PCR select cDNA subtraction. The results identified elevated vascular endothelial growth factor receptor-3 short form splice variant (VEGFR-3(S)) expression in HBxAg positive compared to negative cells. Normally, VEGFR-3 activates Akt signaling in lymphatic endothelial cells, resulting in lymphangiogenesis. In contrast, the results here show that the expression of VEGFR-3(S) is up-regulated in >75% of HBxAg positive hepatocellular carcinoma (HCC) nodules. VEGFR-3(S) up-regulation correlates with the expression of HBxAg, is associated with decreased survival in tumor bearing patients, and when over-expressed in HepG2 cells, strongly stimulated cell growth in culture, in soft agar, and accelerated tumor formation in a ligand independent manner. VEGFR-3(S) siRNA partially blocked the ability of HBxAg to promote hepatocellular growth. In conclusion, HBxAg may short circuit VEGFR-3(S) signaling in liver cancer. Blocking VEGFR-3(S) signaling may be effective in preventing tumor development and/or prolonging survival in tumor bearing patients.
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Affiliation(s)
- Zhaorui Lian
- Department of Pathology, Anatomy and Cell Biology, Thomas Jefferson University, 1020 Locust Street, Philadelphia, PA 19107, USA
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25
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Feitelson MA, Lee J. Hepatitis B virus integration, fragile sites, and hepatocarcinogenesis. Cancer Lett 2006; 252:157-70. [PMID: 17188425 DOI: 10.1016/j.canlet.2006.11.010] [Citation(s) in RCA: 176] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2006] [Revised: 11/08/2006] [Accepted: 11/13/2006] [Indexed: 12/31/2022]
Abstract
Chronic liver disease associated with long term hepatitis B virus (HBV) infection contributes importantly to the development of hepatocellular carcinoma (HCC). A salient feature of these chronic infections is the integration of subgenomic HBV DNA fragments into many different locations within the host DNA, suggesting that integration is random. Although this may promote genetic instability during liver regeneration which accompanies a bout of chronic liver disease, the actual role of integrated HBV DNA in hepatocarcinogenesis is uncertain. Importantly, most integration events retain the HBV open reading frame encoding the HBx antigen (HBxAg), which is the virus contribution to HCC. In addition, many integration events reported in the literature occur near or within fragile sites or other cancer associated regions of the human genome that are prone to instability in tumor development and progression. Genetic instability associated with integration potentially alters the expression of oncogenes, tumor suppressor genes, and microRNAs (miRNAs) that may contribute importantly to tumorigenesis. If so, then selected integration events may alter pathways that are rate limiting in hepatocarcinogenesis, thereby providing targets with diagnostic/prognostic potential and for therapeutic intervention.
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Affiliation(s)
- Mark A Feitelson
- Department of Pathology, Anatomy and Cell Biology, Kimmel Cancer Center, Thomas Jefferson University, 1020 Locust Street, Philadelphia, PA 19107, USA.
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26
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Liu J, Lian Z, Han S, Waye MMY, Wang H, Wu MC, Wu K, Ding J, Arbuthnot P, Kew M, Fan D, Feitelson MA. Downregulation of E-cadherin by hepatitis B virus X antigen in hepatocellullar carcinoma. Oncogene 2006; 25:1008-17. [PMID: 16247464 DOI: 10.1038/sj.onc.1209138] [Citation(s) in RCA: 92] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Hepatitis B virus (HBV)-encoded X antigen (HBxAg) contributes to the development of hepatocellular carcinoma (HCC). A frequent characteristic of HCC is reduced or absent expression of the cell adhesion protein, E-cadherin, although it is not known whether HBxAg plays a role. To address this, the levels of E-cadherin were determined in HBxAg-positive and -negative HepG2 cells in culture, and in tumor and surrounding nontumor liver from a panel of HBV carriers. The results showed an inverse relationship between HBxAg and E-cadherin expression both in tissue culture and in vivo. In HBxAg-positive cells, E-cadherin was suppressed at both the mRNA and protein levels. This was associated with hypermethylation of the E-cadherin promoter. Depressed E-cadherin correlated with HBxAg trans-activation function, as did the migration of HepG2 cells in vitro. Decreased expression of E-cadherin was also associated with the accumulation of beta-catenin in the cytoplasm and/or nuclei in tissues and cell lines, which is characteristic of activated beta-catenin. Additional work showed that HBxAg-activated beta-catenin. Together, these results suggest that the HBxAg is associated with decreased expression of E-cadherin, accumulation of beta-catenin in the cytoplasm and nucleus, and increased cell migration, which may contribute importantly to hepatocarcinogenesis.
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Affiliation(s)
- J Liu
- Department of Pathology, Anatomy, and Cell Biology, Thomas Jefferson University, Philadelphia, PA 19107, USA, and State Key Laboratory for Cancer Biology, Department of Digestive Diseases, Xijing Hospital, Xi'an, Shaanxi, Peoples Republic of China
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Lian Z, Liu J, Li L, Li X, Clayton M, Wu MC, Wang HY, Arbuthnot P, Kew M, Fan D, Feitelson MA. Enhanced cell survival of Hep3B cells by the hepatitis B x antigen effector, URG11, is associated with upregulation of beta-catenin. Hepatology 2006; 43:415-24. [PMID: 16496348 DOI: 10.1002/hep.21053] [Citation(s) in RCA: 52] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Intrahepatic expression of hepatitis B x antigen (HBxAg) is associated with the development of hepatocellular carcinoma (HCC), perhaps through trans-activation of selected cellular genes. When this was examined by PowerBlot analysis, upregulated levels of beta-catenin and several known beta-catenin effectors were observed in HBxAg-positive compared with HBxAg-negative HepG2 cells. When HBxAg was introduced into Hep3B cells, upregulated expression of wild-type beta-catenin was observed. This was also observed in Hep3B cells overexpressing the HBxAg upregulated gene, URG11. Upregulated expression of URG11 and beta-catenin correlated with HBxAg trans-activation function. Transient transfection assays with fragments of the beta-catenin promoter showed that it was activated by both HBxAg and URG11 and inhibited by URG11-specific small inhibitory RNA. The latter also inhibited the growth of Hep3BX cells in a serum-free medium, which correlated with depressed levels of beta-catenin. Activation of beta-catenin effector genes was observed in cells stably expressing HBxAg or overexpressing URG11 compared with control cells transfected with the pTOPFLASH reporter plasmid. Extensive costaining between HBxAg, URG11, and beta-catenin was observed in infected liver and HCC nodules, suggesting a close relationship in vivo. In conclusion, wild-type beta-catenin is activated by HBxAg, in part, through the upregulated expression of the HBxAg effector URG11. URG11 stimulates the beta-catenin promoter and hepatocellular growth and survival. These observations also suggest that URG11 may be a regulatory element in the beta-catenin signaling pathway and may be a target for chemoprevention of HCC.
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Affiliation(s)
- Zhaorui Lian
- Department of Pathology, Anatomy and Cell Biology, Thomas Jefferson University, Philadelphia, PA 19107, USA
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Dufner A, Pownall S, Mak TW. Caspase recruitment domain protein 6 is a microtubule-interacting protein that positively modulates NF-kappaB activation. Proc Natl Acad Sci U S A 2006; 103:988-93. [PMID: 16418290 PMCID: PMC1327733 DOI: 10.1073/pnas.0510380103] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Proteins containing a caspase recruitment domain (CARD) play pivotal roles in signal transduction leading to apoptosis and NF-kappaB activation and inflammation. Here we identify and characterize human and mouse CARD protein 6 (CARD6), CARD-containing proteins of unique structure. CARD6 associates with microtubules and interacts with receptor-interacting protein (RIP)-like interacting caspase-like apoptosis regulatory protein kinase (RICK), a CARD-containing member of the RIP family of protein kinases. These kinases are involved in multiple NF-kappaB signaling pathways important for innate and adaptive immune responses. Surprisingly, the CARDs of CARD6 and RICK were not required for their interaction; instead, mutational analysis revealed that the CARD of CARD6 negatively controls the association of these molecules. CARD6 also binds to RIP1, a RIP kinase homologue that lacks a CARD but contains a C-terminal death domain. Coexpression of RICK targets CARD6 to aggresomes via a mechanism that requires the CARD of RICK. Importantly, CARD6 expression has a synergistic effect on NF-kappaB activation induced by several independent signal transduction pathways. In summary, our results indicate that CARD6 is a regulator of NF-kappaB activation that modulates the functions of RIP kinase family members.
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Affiliation(s)
- Almut Dufner
- Campbell Family Institute for Breast Cancer Research, Toronto, ON, Canada M5G 2C1
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Guo L, Guo Y, Xiao S, Shi X. Protein kinase p-JNK is correlated with the activation of AP-1 and its associated Jun family proteins in hepatocellular carcinoma. Life Sci 2005; 77:1869-78. [PMID: 15927205 DOI: 10.1016/j.lfs.2005.03.019] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2004] [Accepted: 03/21/2005] [Indexed: 01/09/2023]
Abstract
To study the role of c-Jun N-terminal kinase (JNK) and its relation to transcription factor AP-1 and Jun family proteins in hepatocellular carcinoma (HCC) with or without hepatitis B virus (HBV) infection. Immunohistochemical and in situ hybridization techniques were performed for studying phosphorylated JNK (p-JNK), c-Jun, JunB, JunD and AP-1 in 40 cases of human HCC and corresponding nontumoral tissues. Positive staining of nucleus for p-JNK, c-Jun, JunD and AP-1 was presented in 28 (70%), 29 (72.5%), 32 (80%) and 25 (62.5%) in cancer cells respectively, while 0%, 28%, 17.5% and 10% in adjacent non-tumor tissues. The expression levels of p-JNK, c-Jun, JunD and AP-1 were significantly and positively correlated with each other and with HBsAg positive rate (P<0.05). JunB was negative staining in both cancer cells and non-tumor tissues of all cases. JNK phosphorylation may correlate with AP-1 activation and the expression of c-Jun and JunD in HCC. JNK/c-Jun/JunD/AP-1 signaling pathway may play an important role in the pathogenesis of HBV-associated HCC. JunB may not be involved in the process.
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Affiliation(s)
- Linlang Guo
- Department of Pathology, Zhujiang Hospital, Guangzhou, China.
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Ji D, Cheng J, Chen GF, Liu Y, Wang L, Guo J. Study of transactivating effect of pre-S2 protein of hepatitis B virus and cloning of genes transactivated by pre-S2 protein with suppression subtractive hybridization. World J Gastroenterol 2005; 11:5438-43. [PMID: 16222733 PMCID: PMC4320350 DOI: 10.3748/wjg.v11.i35.5438] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
AIM: To investigate the transactivating effect of pre-S2 protein of hepatitis B virus (HBV) and construct a subtractive cDNA library of genes transactivated by pre-S2 protein with suppression subtractive hybridization (SSH) technique, and to pave the way for elucidating the pathogenesis of HBV infection.
METHODS: pcDNA3.1(-)-pre-S2 containing pre-S2 region of HBV genome was constructed by routine molecular methods. HepG2 cells were cotransfected with pcDNA3.1(-)-pre-S2/pSV-lacZ and empty pcDNA3.1(-)/pSV-lacZ. After 48 h, cells were collected and detected for the expression of β-galactosidase (β-gal). SSH and bioinformatics techniques were used, the mRNA of HepG2 cells transfected with pcDNA3.1(-)-pre-S2 and pcDNA3.1(-) empty vector was isolated, respectively, cDNA was synthesized. After digestion with restriction enzyme RsaI, cDNA fragments were obtained. Tester cDNA was then divided into two groups and ligated to the specific adaptor 1 and adaptor 2, respectively. After tester cDNA was hybridized with driver cDNA twice and underwent two times of nested PCR, amplified cDNA fragments were subcloned into pGEM-Teasy vectors to set up the subtractive library. Amplification of the library was carried out with E.coli strain DH5α. The cDNA was sequenced and analyzed in GenBank with Blast search after PCR.
RESULTS: The pre-S2 mRNA could be detected in HepG2 cells transfected with pcDNA3.1(-)-pre-S2 plasmid. The activity of β-gal in HepG2 cells transfected with pcDNA3.1(-)-pre-S2/pSV-lacZ was 7.0 times higher than that of control plasmid (P<0.01). The subtractive library of genes transactivated by HBV pre-S2 protein was constructed successfully. The amplified library contains 96 positive clones. Colony PCR showed that 86 clones contained 200-1 000 bp inserts. Sequence analysis was performed in 50 clones randomly, and the full length sequences were obtained with bioinformatics method and searched for homologous DNA sequence from GenBank, altogether 25 coding sequences were obtained, these cDNA sequences might be the target genes transactivated by pre-S2 protein.
CONCLUSION: The pre-S2 protein of HBV has transactivating effect on SV40 early promoter. The obtained sequences may be target genes transactivated by pre-S2 protein among which some genes coding proteins involved in cell cycle regulation, metabolism, immunity, signal transduction and cell apoptosis.This finding brings some new clues for studying the biological functions of pre-S2 protein and further understanding of HBV hepatocarcinogesis.
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Affiliation(s)
- Dong Ji
- The 7th Department of Infectious Diseases, The 302 Hospital of PLA, Beijing 100039, China.
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31
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Michielsen PP, Francque SM, van Dongen JL. Viral hepatitis and hepatocellular carcinoma. World J Surg Oncol 2005; 3:27. [PMID: 15907199 PMCID: PMC1166580 DOI: 10.1186/1477-7819-3-27] [Citation(s) in RCA: 102] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2004] [Accepted: 05/20/2005] [Indexed: 12/12/2022] Open
Abstract
BACKGROUND Hepatocellular carcinoma (HCC) is one of the most common malignant tumors in the world. The incidence of HCC varies considerably with the geographic area because of differences in the major causative factors. Chronic hepatitis B and C, mostly in the cirrhotic stage, are responsible for the great majority of cases of HCC worldwide. The geographic areas at the highest risk are South-East Asia and sub-Saharan Africa, here hepatitis B is highly endemic and is the main cause of HCC. In areas with an intermediate rate of HCC such as Southern Europe and Japan, hepatitis C is the predominant cause, whereas in low rate areas such as Northern Europe and the USA, HCC is often related to other factors as alcoholic liver disease. There is a rising incidence in HCC in developed countries during the last two decades, due to the increasing rate of hepatitis C infection and improvement of the clinical management of cirrhosis. METHODS This article reviews the literature on hepatitis and hepatocellular carcinoma. The Medline search was carried out using these key words and articles were selected on epidemiology, risk factors, screening, and prevention of hepatocellular carcinoma. RESULTS Screening of patients with advanced chronic hepatitis B and C with hepatic ultrasound and determination of serum alfa-fetoprotein may improve the detection of HCC, but further studies are needed whether screening improves clinical outcome. Hepatitis B and C viruses (HBV/HCV) can be implicated in the development of HCC in an indirect way, through induction of chronic inflammation, or directly by means of viral proteins or, in the case of HBV, by creation of mutations by integration into the genome of the hepatocyte. CONCLUSION The most effective tool to prevent HCC is avoidance of the risk factors such as viral infection. For HBV, a very effective vaccine is available. Preliminary data from Taiwan indicate a protective effect of universal vaccination on the development of HCC. Vaccination against HBV should therefore be a health priority. In patients with chronic hepatitis B or C, interferon-alfa treatment in a noncirrhotic stage is protective for HCC development in responders, probably by prevention of cirrhosis development. When cirrhosis is already present, the protective effect is less clear. For cirrhosis due to hepatitis B, a protective effect was demonstrated in Oriental, but not in European patients. For cirrhosis due to hepatitis C, interferon-alfa treatment showed to be protective in some studies, especially in Japan with a high incidence of HCC in untreated patients. Virological, but also merely biochemical response, seems to be associated with a lower risk of development of HCC. As most studies are not randomized controlled trials, no definitive conclusions on the long-term effects of interferon-alfa in HBV or HCV cirrhosis can be established. Especially in hepatitis C, prospective studies should be performed using the more potent reference treatments for cirrhotics, namely the combination of peginterferon and ribavirin.
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Affiliation(s)
- Peter P Michielsen
- Division of Gastroenterology and Hepatology University Hospital Antwerp, Belgium
| | - Sven M Francque
- Division of Gastroenterology and Hepatology University Hospital Antwerp, Belgium
| | - Jurgen L van Dongen
- Division of Gastroenterology and Hepatology University Hospital Antwerp, Belgium
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de Moura PR, Rui E, de Almeida Gonçalves K, Kobarg J. The cysteine residues of the hepatitis B virus onco-protein HBx are not required for its interaction with RNA or with human p53. Virus Res 2005; 108:121-31. [PMID: 15681062 DOI: 10.1016/j.virusres.2004.08.018] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2004] [Revised: 08/23/2004] [Accepted: 08/26/2004] [Indexed: 11/28/2022]
Abstract
The hepatitis B virus (HBV) protein HBx has been implicated to induce liver cancer in transgenic mice and transactivates a variety of viral and cellular promoters. The 17 kDa protein HBx consists of 154 amino acids, contains 10 cysteine residues and is translated during the viral infection. It has been shown previously that the HBx protein is able to bind to singlestranded DNA and RNA. This nucleic acid binding activity might be relevant for HBx oncogenic character. Furthermore, HBx has been reported to interact with a series of cellular proteins, especially with transcription factors, including the tumor suppressor protein p53. To evaluate the importance of the cysteine residues in HBx for its interaction with RNA and p53 we expressed full-length HBx-wt as well as several truncated mini-HBx(18-142) proteins with multiple cysteine to serine point mutations as 6xHis fusion proteins in Escherichia coli. Using UV cross-linking assays we demonstrate that all truncated mini-HBx proteins with cysteine/serine point mutations maintained the ability to bind to an AU-38 RNA oligonucleotide. Furthermore, we performed in vitro binding assays of selected HBx mutants with GST-p53, circular dichroism spectroscopic analysis of the mutant HBx protein secondary structure and a p53 based transcription activation assay in yeast cells. In summary, our data suggest that the cysteine residues in the HBx protein are of minor importance for its interaction with both RNA and the p53 protein.
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Affiliation(s)
- Patricia Ribeiro de Moura
- Centro de Biologia Molecular Estrutural, Laboratório Nacional de Luz Síncrotron, Rua Giuseppe Máximo Scolfaro 10.000, CP 6192, Campinas, SP, CEP 13084-971, Brazil
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Chou YC, Jeng KS, Chen ML, Liu HH, Liu TL, Chen YL, Liu YC, Hu CP, Chang C. Evaluation of transcriptional efficiency of hepatitis B virus covalently closed circular DNA by reverse transcription-PCR combined with the restriction enzyme digestion method. J Virol 2005; 79:1813-23. [PMID: 15650205 PMCID: PMC544084 DOI: 10.1128/jvi.79.3.1813-1823.2005] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
Virus persistence in chronic hepatitis B patients is due to the sustaining level of covalently closed circular DNA (cccDNA) within the nuclei of infected hepatocytes. In this study, we used a modified 1.3-fold hepatitis B virus (HBV) genome, with a BclI genetic marker embedded in the redundancy region, to examine the transcriptional activity of cccDNA and the effect of the HBx protein on transcriptional regulation. After harvesting total RNA from transfected cells or stable lines, we specifically identified and monitored the transcripts from cccDNA by using reverse transcription-PCR (RT-PCR) combined with the restriction enzyme digestion method. In this approach, we have found that (i) RT-PCR combined with detection of the BclI marker is a highly specific method for distinguishing cccDNA-derived transcripts from the original integrated viral genome, (ii) the transcriptional ability of cccDNA was less efficient than that from the integrated viral genome, and (iii) the transcriptional activity of cccDNA was significantly regulated by the HBx protein, a potential transcription activator. In conclusion, we provided a tool with which to elucidate the transcriptional regulation of cccDNA and clarified the transcriptional regulation mechanism of HBx on cccDNA. The results obtained may be helpful in the development of a clinical intervention for patients with chronic HBV infections.
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Affiliation(s)
- Yu-Chi Chou
- Institute of Microbiology and Immunology, National Yang-Ming University, Taipei, Taiwan
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Heo KS, Lee SJ, Ko JH, Lim K, Lim KT. Glycoprotein isolated from Solanum nigrum L. inhibits the DNA-binding activities of NF-κB and AP-1, and increases the production of nitric oxide in TPA-stimulated MCF-7 cells. Toxicol In Vitro 2004; 18:755-63. [PMID: 15465640 DOI: 10.1016/j.tiv.2004.03.003] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2003] [Accepted: 03/08/2004] [Indexed: 10/26/2022]
Abstract
Solanum nigrum L. (SNL) has been used in traditional folk medicine to treat numerous cancers. We isolated a glycoprotein (150 kDa) from SNL and tested its effect on the modulation of transcriptional factors (NF-kappa B and AP-1) and iNO production in TPA induced-MCF-7 cells, which are part of the human breast cancer cell line, without estrogen receptors. However, the mechanism of SNL glycoprotein in pharmacological and biochemical actions in cancer cells has not been studied. To test the effect of SNL glycoprotein on the DNA-binding activities of nuclear factor-kappa B (NF-kappaB) and activator protein-1 (AP-1), and nitric oxide (NO) production, these experiments were carried out using electrophoretic mobility shift assays (EMSA), western blot analysis, and the Griess method. Results in this experiment showed that SNL glycoprotein inhibits 12-O-Tetra decanoylphorbol-13-acetate (TPA; 100 nM)-induced DNA-binding activities of NF-kappaB and AP-1, and enhances NO production in MCF-7 cells. That is, our results indicated that SNL glycoprotein has the capacity to modulate the TPA-induced DNA-binding activities of transcription factors and NO production, which play a critical role with respect to cytotoxicity in MCF-7 cells. Therefore, SNL glycoprotein might be one of the agents that blocks TPA-mediated signal responses in tumor cells.
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Affiliation(s)
- K S Heo
- 521 Molecular Biochemistry Laboratory and Biodefensive Substances Group, Institute of Biotechnology, Chonnam National University, 300 Yongbong Dong, Bukgu, Kwangju 500757, South Korea
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Hann HWL, Lee J, Bussard A, Liu C, Jin YR, Guha K, Clayton MM, Ardlie K, Pellini MJ, Feitelson MA. Preneoplastic Markers of Hepatitis B Virus-Associated Hepatocellular Carcinoma. Cancer Res 2004; 64:7329-35. [PMID: 15492253 DOI: 10.1158/0008-5472.can-04-1095] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Hepatitis B virus (HBV) carriers are at high risk for the development of hepatocellular carcinoma (HCC), but there are no reliable markers that will identify such high-risk carriers. The objective of this work is to identify serologic markers that may indicate the early presence of HCC. Since HBV-encoded X antigen (HBxAg) likely contributes to HCC by up- or down-regulation of host gene expression, X positive and negative HepG2 cells were made and subjected to cDNA subtraction. When specific ELISAs were constructed measuring differentially expressed antigens and corresponding antibodies, antibodies to several differentially expressed genes were detected. In cross-sectional and longitudinal studies, antibodies were predominantly present in patients with HBV-associated cirrhosis and HCC, but not in most carriers with hepatic inflammation alone or without active liver disease. Antibodies were also present in patients with hepatitis C virus (HCV)-related HCC, but rarely detected in sera from uninfected individuals, those with tumors other than HCC, or those with drug-induced hepatitis. Statistical analysis showed that HCC patients with four or more antibodies detectable before the appearance of HCC had decreased survival, suggesting that these markers may reflect stepwise hepatocarcinogenesis. Hence, these antibodies may serve as preneoplastic markers for HCC in HBV carriers with chronic liver disease, and may be identified by a simple blood test.
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Affiliation(s)
- Hie-Won L Hann
- Department of Medicine, Division of Gastroenterology and Hepatology, Jefferson Medical College, Thomas Jefferson University Hospital, Philadelphia, Pennsylvania, USA
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Ji D, Cheng J, Dong J, Liu Y, Wang JJ, Guo J. Screening and identification of genes trans-regulated by HBV pre-S2 protein with cDNA microarray. Shijie Huaren Xiaohua Zazhi 2004; 12:1559-1563. [DOI: 10.11569/wcjd.v12.i7.1559] [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
Abstract
AIM: To understand the target genes up-regulated or down-regulated by HBV pre-S2 protein, we compared the differentially expressed genes between the hepatoblastoma cell line HepG2 transfected by pcDNA3.1(-) and pcDNA3.1(-)-preS2, respectively with cDNA microarray technique.
METHODS: The HBV pre-S2 coding DNA fragment was amplified with polymerase chain reaction (PCR) technique by using G376-7 plasmid containing the full length of HBV genome as the template. The expressive vector of pcDNA3.1-preS2 was constructed by routine molecular biological methods. The HepG2 cells were transfected by pcDNA3.1(-) and pcDNA3.1(-)-preS2, respectively, using FuGENE6 transfection reagent. The total RNA was isolated and reversely transcribed. The cDNAs were subjected for microarray screening with 1 152 cDNA probes.
RESULTS: The expressive vector was constructed and confirmed by restriction enzyme digestion and DNA sequencing analysis. High quality mRNA and cDNA were prepared and successful microarray screening conducted. From the scanning results, it was found 42 genes were up-regulated and 36 genes down-regulated by pre-S2 protein of HBV.
CONCLUSION: HBV pre-S2 protein is a transactivator. The expression of pre-S2 protein affects the expression spectrum of HBV infected hepatocyte.
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Norton PA, Reis HMGPV, Prince S, Larkin J, Pan J, Liu J, Gong Q, Zhu M, Feitelson MA. Activation of fibronectin gene expression by hepatitis B virus x antigen. J Viral Hepat 2004; 11:332-41. [PMID: 15230856 DOI: 10.1111/j.1365-2893.2004.00555.x] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/09/2022]
Abstract
The development of fibrosis and cirrhosis during chronic hepatitis B virus (HBV) infection correlates with the persistent expression of HBV x antigen (HBxAg), which acts in part, by stimulating selected signal transduction pathways, including nuclear factor kappa B (NF-kappa B). To identify NF-kappa B responsive genes that are differentially expressed in HBxAg-positive cells, HepG2 cells were stably transfected with HBxAg, and then with pZeoSV2 or pZeoSV2-I kappa B alpha. When RNAs from each culture were compared by PCR-select cDNA subtraction, fibronectin (FN) mRNA was shown to be strongly down-regulated by I kappa B alpha. Up-regulated expression of FN and co-expression between FN and HBxAg were observed in liver sections from HBV carriers that were stained for HBxAg and analysed for FN mRNA by in situ hybridization (ISH). In liver cell cultures, HBxAg increased the levels of FN mRNA and protein. This was because of the HBxAg-mediated trans-activation of the FN promoter, which was NF-kappa B-dependent. HBxAg also antagonized the repression of the FN promoter by the tumour suppressor, p53. Hence, the FN gene may be a natural target for HBxAg trans-activation, perhaps through activation of NF-kappa B and inactivation of p53, thereby contributing to the accumulation of FN in the liver over the course of chronic HBV infection.
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Affiliation(s)
- P A Norton
- Department of Biochemistry and Molecular Pharmacology, Jefferson Center for Biomedical Research, Thomas Jefferson University, Philadelphia, PA 18901, USA.
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Pellerin M, Lopez-Aguirre Y, Penin F, Dhumeaux D, Pawlotsky JM. Hepatitis C virus quasispecies variability modulates nonstructural protein 5A transcriptional activation, pointing to cellular compartmentalization of virus-host interactions. J Virol 2004; 78:4617-27. [PMID: 15078944 PMCID: PMC387712 DOI: 10.1128/jvi.78.9.4617-4627.2004] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
Hepatitis C virus (HCV) behaves in infected patients as a complex mixture of genetically distinct but closely related variants referred to as a "quasispecies." By using quasispecies analysis strategies, we showed that HCV nonstructural protein 5A (NS5A) has a quasispecies distribution in infected humans and that NS5A quasispecies undergo significant genetic evolution over time, as a result of random accumulation of nucleotide mutations during replication. Genetic evolution of the NS5A quasispecies results in sporadic amino acid changes in the protein sequence. By using the functional in vitro model of HCV NS5A transcriptional activation in Saccharomyces cerevisiae, we showed that natural NS5A quasispecies variants induce different levels of transcriptional activation, according to the charge of the residues (and possibly minor conformational changes) in the quasispecies variant sequence. These findings show that the accumulation of mutations on HCV genomes during replication randomly generates variant proteins with quantitatively different functional properties. The fact that each new variant protein is initially produced in a single infected hepatocyte and may or may not subsequently spread throughout the liver (depending on the replication capacities of the variant virus) points to cellular compartmentalization of virus-host interactions during chronic infection. This feature of quasispecies-distributed viruses could play an important role in various aspects of the viral life cycle and related disease.
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Affiliation(s)
- Muriel Pellerin
- Department of Virology INSERM U635, Hôpital Henri Mondor, Université Paris XII, 94010 Créteil, France
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Lian Z, Liu J, Li L, Li X, Tufan NLS, Wu MC, Wang HY, Arbuthnot P, Kew M, Feitelson MA. Human S15a expression is upregulated by hepatitis B virus X protein. Mol Carcinog 2004; 40:34-46. [PMID: 15108328 DOI: 10.1002/mc.20012] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
The hepatitis B virus (HBV)-encoded X antigen (HBxAg) may contribute to the development of hepatocellular carcinoma (HCC) through the upregulated expression of selected cellular genes. To identify these genes, RNAs isolated from HBxAg-positive and -negative HepG2 cells were compared by PCR select cDNA subtraction. One gene overexpressed in HBxAg-positive cells by Northern and Western blotting is the ribosomal protein S15a. The S15a mRNA is 535 base pairs, encoding a protein 130 amino acids long with a molecular weight of 14.3 kDa. S15a expression was upregulated in HBV-infected livers, where it costained with HBxAg. Overexpression of S15a stimulated cell growth, colony formation in soft agar, and tumor formation in SCID mice. Hence, HBxAg upregulated the expression of S15a, the latter of which participates in the development of HCC, perhaps by altering the integrity of translation.
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Affiliation(s)
- Zhaorui Lian
- Department of Pathology, Anatomy, and Cell Biology, Thomas Jefferson University, Philadelphia, Pennsylvania 19107-6749, USA
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Pan J, Clayton M, Feitelson MA. Hepatitis B virus X antigen promotes transforming growth factor-beta1 (TGF-beta1) activity by up-regulation of TGF-beta1 and down-regulation of alpha2-macroglobulin. J Gen Virol 2004; 85:275-282. [PMID: 14769885 DOI: 10.1099/vir.0.19650-0] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
Hepatitis B virus (HBV) X antigen (HBxAg) may contribute to the development of hepatocellular carcinoma (HCC) by activation of signalling pathways such as NF-kappaB. To identify NF-kappaB target genes differentially expressed in HBxAg-positive compared to -negative cells, HepG2 cells consistently expressing HBxAg (HepG2X cells) were stably transfected with pZeoSV2 or pZeoSV2-IkappaBalpha. mRNA from each culture was isolated and compared by PCR select cDNA subtraction. The results showed lower levels of alpha(2)-macroglobulin (alpha(2)-M) in HepG2X-pZeoSV2 compared to HepG2X-pZeoSV2-IkappaBalpha cells. This was confirmed by Northern and Western blotting, and by measurement of extracellular alpha(2)-M levels. Elevated transforming growth factor-beta1 (TGF-beta1) levels were also seen in HepG2X compared to control cells. Serum-free conditioned medium (SFCM) from HepG2X cells suppressed DNA synthesis in a TGF-beta-sensitive cell line, Mv1Lu. The latter was reversed when the SFCM was pretreated with exogenous, activated alpha(2)-M or with anti-TGF-beta. Since elevated TGF-beta1 promotes the development of many tumour types, these observations suggest that the HBxAg-mediated alteration in TGF-beta1 and alpha(2)-M production may contribute importantly to the pathogenesis of HCC.
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Affiliation(s)
- Jingbo Pan
- Department of Pathology, Anatomy and Cell Biology, Thomas Jefferson University, Room 222 Alumni Hall, 1020 Locust Street, Philadelphia, PA 19107, USA
| | - Marcy Clayton
- Department of Pathology, Anatomy and Cell Biology, Thomas Jefferson University, Room 222 Alumni Hall, 1020 Locust Street, Philadelphia, PA 19107, USA
| | - Mark A Feitelson
- Department of Microbiology and Immunology, Kimmel Cancer Center, Thomas Jefferson University, Philadelphia, PA 19107, USA
- Department of Pathology, Anatomy and Cell Biology, Thomas Jefferson University, Room 222 Alumni Hall, 1020 Locust Street, Philadelphia, PA 19107, USA
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42
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Liu Y, Cheng J, Wang L, Wang JJ, Lu YY, Li K. Cloning of gene 1 transactivated by C-terminally truncated middle surface protein of hepatitis B virus. Shijie Huaren Xiaohua Zazhi 2003; 11:1102-1106. [DOI: 10.11569/wcjd.v11.i8.1102] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
AIM To investigate the transactivation effects of C-terminally truncated middle surface protein (MHBst) of hepatitis B virus (HBV) by differential display method. To clone new gene with unknown function that could be transactivated by MHBst with suppression subtractive hybridization (SSH), and pave the way for the study and better understanding of the transactivation effects of MHBst.
METHODS Polymerase chain reaction (PCR)technique was employed to amplify the coding sequence of MHBst, and the expressive vector pcDNA3.1-MHBst was constructed by routine molecular biological method. The differentially expressed genes were screened and identified by SSH method between the HepG2 cells transfected with pcDNA3.1-MHBst and the vector pcDNA3.1, respectively. Bioinformatics techniques were used to search homologously expressed sequence tag (EST) and full-length coding sequence transactivated by MHBst. The mRNA was purified from HepG2 cells and the DNA fragment was amplified by reverse transcription PCR (RT-PCR) technique. The coding sequence was analyzed by bioinformatics. The new gene transactivated by MHBst was designated as target gene 1 transactivated by truncated middle surface protein of HBV (TTP1).
RESULTS The expressive vector pcDNA3.1-MHBst was constructed and confirmed by restriction enzyme digestion and sequencing. SSH method was employed for the screening and identification of the differentially expressed genes from the HepG2 cells transfected with pcDNA3.1-MHBst and pcDNA3.1, respectively. Among the target genes, we identified a new gene with unknown function and deposited its sequence into GenBank. From the homology search, we evaluated this gene as a new gene with unknown function.
CONCLUSION The gene 1 transactivated by C-terminally truncated middle surface protein of hepatitis B virus was identified.
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Affiliation(s)
- Yan Liu
- Gene Therapy Research Center, Institute of Infectious Diseases, The 302 Hospital of PLA, Beijing 100039, China
| | - Jun Cheng
- Gene Therapy Research Center, Institute of Infectious Diseases, The 302 Hospital of PLA, Beijing 100039, China
| | - Lin Wang
- Gene Therapy Research Center, Institute of Infectious Diseases, The 302 Hospital of PLA, Beijing 100039, China
| | - Jian-Jun Wang
- Gene Therapy Research Center, Institute of Infectious Diseases, The 302 Hospital of PLA, Beijing 100039, China
| | - Yin-Ying Lu
- Gene Therapy Research Center, Institute of Infectious Diseases, The 302 Hospital of PLA, Beijing 100039, China
| | - Ke Li
- Gene Therapy Research Center, Institute of Infectious Diseases, The 302 Hospital of PLA, Beijing 100039, China
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43
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Lian Z, Liu J, Li L, Li X, Tufan NLS, Clayton M, Wu MC, Wang HY, Arbuthnot P, Kew M, Feitelson MA. Upregulated expression of a unique gene by hepatitis B x antigen promotes hepatocellular growth and tumorigenesis. Neoplasia 2003; 5:229-44. [PMID: 12869306 PMCID: PMC1502406 DOI: 10.1016/s1476-5586(03)80055-6] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
Hepatitis B x antigen (HB x Ag) is a trans-activating protein that may be involved in hepatocarcinogenesis, although few natural effectors of HB x Ag that participate in this process have been identified. To identify additional effectors, whole cell RNA isolated from HB x Ag-positive and HB x Ag-negative HepG2 cells were compared by polymerase chain reaction select cDNA subtraction, and one clone, upregulated gene, clone 11 (URG11), was chosen for further characterization. Elevated levels of URG11 mRNA and protein were observed in HB x Ag-positive compared to HB x Ag-negative HepG2 cells. Costaining was observed in infected liver (P < 0.01). URG11 stimulated cell growth in culture (P < 0.01), anchorage-independent growth in soft agar (P < 0.001), and accelerated tumor formation (P < 0.01), and yielded larger tumors (P < 0.02) in SCID mice injected subcutaneously with HepG2 cells. These data suggest that URG11 is a natural effector of HB x Ag that may promote the development of hepatocellular carcinoma.
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Affiliation(s)
- Zhaorui Lian
- Department of Pathology, Anatomy, and Cell Biology, Thomas Jefferson University, Philadelphia, PA 19107, USA
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44
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Chen SY, Kao CF, Chen CM, Shih CM, Hsu MJ, Chao CH, Wang SH, You LR, Lee YHW. Mechanisms for inhibition of hepatitis B virus gene expression and replication by hepatitis C virus core protein. J Biol Chem 2003; 278:591-607. [PMID: 12401801 DOI: 10.1074/jbc.m204241200] [Citation(s) in RCA: 128] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
We have demonstrated previously that the core protein of hepatitis C virus (HCV) exhibits suppression activity on gene expression and replication of hepatitis B virus (HBV). Here we further elucidated the suppression mechanism of HCV core protein. We demonstrated that HCV core protein retained the inhibitory effect on HBV gene expression and replication when expressed as part of the full length of HCV polyprotein. Based on the substitution mutational analysis, our results suggested that mutation introduced into the bipartite nuclear localization signal of the HCV core protein resulted in the cytoplasmic localization of core protein but did not affect its suppression ability on HBV gene expression. Mutational studies also indicated that almost all dibasic residue mutations within the N-terminal 101-amino acid segment of the HCV core protein (except Arg(39)-Arg(40)) impaired the suppression activity on HBV replication but not HBV gene expression. The integrity of Arg residues at positions 101, 113, 114, and 115 was found to be essential for both suppressive effects, whereas the Arg residue at position 104 was important only in the suppression of HBV gene expression. Moreover, our results indicated that the suppression on HBV gene expression was mediated through the direct interaction of HCV core protein with the trans-activator HBx protein, whereas the suppression of HBV replication involved the complex formation between HBV polymerase (pol) and the HCV core protein, resulting in the structural incompetence for the HBV pol to bind the package signal and consequently abolished the formation of the HBV virion. Altogether, this study suggests that these two suppression effects on HBV elicited by the HCV core protein likely depend on different structural context but not on nuclear localization of the core protein, and the two effects can be decoupled as revealed by its differential targets (HBx or HBV pol) on these two processes of the HBV life cycle.
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Affiliation(s)
- Shiow-Yi Chen
- Institute of Biochemistry and Institute of Microbiology and Immunology, National Yang-Ming University, Taipei, Taiwan 112, Republic of China
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45
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Yun C, Lee JH, Wang JH, Seong JK, Oh SH, Yu DY, Cho H. Expression of hepatitis B virus X (HBx) gene is up-regulated by adriamycin at the post-transcriptional level. Biochem Biophys Res Commun 2002; 296:1157-63. [PMID: 12207895 DOI: 10.1016/s0006-291x(02)02058-2] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
Hepatitis B virus (HBV) X protein (HBx) is thought to be involved in the development of liver cancer and alteration of cellular HBx level may influence the pathological progression of HBV-induced liver diseases. We found that the cellular levels of HBx mRNA transcript and protein in cells were greatly enhanced by adriamycin, a topoisomerase II inhibitor. Up-regulation of HBx mRNA by adriamycin was also observed in HBx transgenic mice, which was accompanied with a significant increase of VEGF mRNA, the downstream target of HBx. When we investigated the underlying mechanism, we found that half-life of HBx mRNA in HBx-expressing Chang cells was about 3h, but was prolonged to >6h in the presence of adriamycin. Moreover, half-life of rapidly degrading HBx protein was determined as about 15min however, it remained almost constant until 60min in the presence of adriamycin. These results provide the first evidence that the cellular level of HBx gene can be increased at the post-transcriptional level.
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Affiliation(s)
- Chawon Yun
- Department of Biochemistry, Ajou University School of Medicine, 5 Wonchon-dong, Paldal-ku, 442-749, Suwon, Republic of Korea
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Yang HI, Lu SN, Liaw YF, You SL, Sun CA, Wang LY, Hsiao CK, Chen PJ, Chen DS, Chen CJ. Hepatitis B e antigen and the risk of hepatocellular carcinoma. N Engl J Med 2002; 347:168-74. [PMID: 12124405 DOI: 10.1056/nejmoa013215] [Citation(s) in RCA: 870] [Impact Index Per Article: 39.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
BACKGROUND The presence of hepatitis B e antigen (HBeAg) in serum indicates active viral replication in hepatocytes. HBeAg is thus a surrogate marker for the presence of hepatitis B virus DNA. We conducted a prospective study to determine the relation between positivity for hepatitis B surface antigen (HBsAg) and HBeAg and the development of hepatocellular carcinoma. METHODS In 1991 and 1992, we enrolled 11,893 men without evidence of hepatocellular carcinoma (age range, 30 to 65 years) from seven townships in Taiwan. Serum samples obtained at the time of enrollment were tested for HBsAg and HBeAg by radioimmunoassay. The diagnosis of hepatocellular carcinoma was ascertained through data linkage with the computerized National Cancer Registry in Taiwan and with death certificates. We performed a multiple regression analysis to determine the relative risk of hepatocellular carcinoma among men who were positive for HBsAg alone or for HBsAg and HBeAg, as compared with those who were negative for both. RESULTS There were 111 cases of newly diagnosed hepatocellular carcinoma during 92,359 person-years of follow-up. The incidence rate of hepatocellular carcinoma was 1169 cases per 100,000 person-years among men who were positive for both HBsAg and HBeAg, 324 per 100,000 person-years for those who were positive for HBsAg only, and 39 per 100,000 person-years for those who were negative for both. After adjustment for age, sex, the presence or absence of antibodies against hepatitis C virus, cigarette-smoking status, and use or nonuse of alcohol, the relative risk of hepatocellular carcinoma was 9.6 (95 percent confidence interval, 6.0 to 15.2) among men who were positive for HBsAg alone and 60.2 (95 percent confidence interval, 35.5 to 102.1) among those who were positive for both HBsAg and HBeAg, as compared with men who were negative for both. CONCLUSIONS Positivity for HBeAg is associated with an increased risk of hepatocellular carcinoma.
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Affiliation(s)
- Hwai-I Yang
- Graduate Institute of Epidemiology, College of Public Health, National Taiwan University, Taipei
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Tufan NLS, Lian Z, Liu J, Pan J, Arbuthnot P, Kew M, Clayton MM, Zhu M, Feitelson MA. Hepatitis Bx antigen stimulates expression of a novel cellular gene, URG4, that promotes hepatocellular growth and survival. Neoplasia 2002; 4:355-68. [PMID: 12082552 PMCID: PMC1531705 DOI: 10.1038/sj.neo.7900241] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2001] [Accepted: 01/24/2002] [Indexed: 12/16/2022]
Abstract
Hepatitis B virus encoded X antigen (HBxAg) may contribute to the development of hepatocellular carcinoma (HCC) by up- or downregulating the expression of cellular genes that promote cell growth and survival. To test this hypothesis, HBxAg-positive and -negative HepG2 cells were constructed, and the patterns of cellular gene expression compared by polymerase chain reaction select cDNA subtraction. The full-length clone of one of these upregulated genes (URG), URG4, encoded a protein of about 104 kDa. URG4 was strongly expressed in hepatitis B-infected liver and in HCC cells, where it costained with HBxAg, and was weakly expressed in uninfected liver, suggesting URG4 was an effector of HBxAg in vivo. Overexpression of URG4 in HepG2 cells promoted hepatocellular growth and survival in tissue culture and in soft agar, and accelerated tumor development in nude mice. Hence, URG4 may be a natural effector of HBxAg that contributes importantly to multistep hepatocarcinogenesis.
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Affiliation(s)
- N Lale Satiroglu Tufan
- Department of Pathology, Anatomy, and Cell Biology, Thomas Jefferson University, 1020 Locust Street, Philadelphia, PA 19107-6799, USA
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48
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Schulte-Frohlinde E, Seidler B, Burkard I, Freilinger T, Lersch C, Erfle V, Foster GR, Classen M. Different activities of type I interferons on hepatitis B virus core promoter regulated transcription. Cytokine 2002; 17:214-20. [PMID: 11991674 DOI: 10.1006/cyto.2001.1000] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
The type I interferons (IFNs) are a group of closely related cytokines which have different signal transduction pathways and different biological activities. Using transient transfection of human hepatoma cells with reporter plasmids containing the firefly/renilla luciferase genes under the control of the HBV-Enhancer (Enh) I, Enh II and core promoter we have investigated the biological activities of 10 recombinant (r) type I IFNs on transcription. Low concentrations of IFN (0.025 ng/ml) had a significant and specific inhibitory effect but the potencies of the different recombinant type I IFNs differed markedly with IFNalpha8 and IFNbeta being six-fold more potent than the least effective subtype (IFNalpha1). However, the addition of IFNalpha5-the subtype produced predominantly in the human liver-did not cause any synergistic effects.The non-natural consensus IFN displayed a more pronounced inhibition of HBV-regulated transcription than IFNalpha8 or IFNalpha2 but not IFNbeta. The INF-induced inhibitory effect was not dependent on the presence of the HBV-Enh1 and in particular of an interferon stimulated response element (ISRE)-like sequence. The characterization of different effects among type I interferons on HBV-regulatory elements may implicate an IFN-subtype-specific role for the pathogenesis and treatment of HBV-infection.
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49
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Jin YM, Yun C, Park C, Wang HJ, Cho H. Expression of hepatitis B virus X protein is closely correlated with the high periportal inflammatory activity of liver diseases. J Viral Hepat 2001; 8:322-30. [PMID: 11555189 DOI: 10.1046/j.1365-2893.2001.00308.x] [Citation(s) in RCA: 57] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Hepatitis B virus X (HBx) protein is a multifunctional protein that exerts dual activity on cell proliferation and death. Although HBx is thought to be a major determinant that leads to hepatocellular carcinoma, its pathophysiological role in humans remains to be established. Attempts have been made to evaluate the role of HBx in liver specimens derived from patients with chronic B viral hepatitis and hepatocellular carcinoma. Among 25 paired liver specimens of hepatocellular carcinoma and corresponding nontumour liver tissues, HBx mRNA was hardly detected and was significantly lower than other HBV transcripts. An immunohistochemical study demonstrated that expression of HBx protein was also lower than other HBV gene products. Interestingly, however, expression of HBx protein changed with the progression of chronic hepatitis. HBx was expressed in 5.0% of patients with chronic hepatitis without cirrhosis but increased to 44.8% in chronic hepatitis with cirrhosis. In contrast, only one (3.7%) of 27 hepatocellular carcinomas showed HBx positivity whereas 29.6% of surrounding nontumour tissues was still HBx-positive. These results suggest that HBx may play a major role at the promotion stage of carcinogenesis. Noticeably, HBx-positive cells were preferentially localized in the periportal region of chronic hepatitis or periphery of cirrhotic nodules where high necroinflammatory activity was accompanied. We found a positive correlation between HBx expression and periportal inflammatory activity (P < 0.001). Thus, HBx may potentiate cell destruction and regeneration of liver that provide an opportunity for the accumulation of genetic mutations, which contribute to multistep hepatocarcinogenesis.
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MESH Headings
- Carcinoma, Hepatocellular/genetics
- Carcinoma, Hepatocellular/metabolism
- Carcinoma, Hepatocellular/pathology
- Carcinoma, Hepatocellular/virology
- Gene Expression Regulation, Viral
- Hepatitis B virus/genetics
- Hepatitis B virus/metabolism
- Hepatitis B, Chronic/metabolism
- Hepatitis B, Chronic/pathology
- Hepatitis B, Chronic/virology
- Hepatocytes/metabolism
- Hepatocytes/pathology
- Hepatocytes/virology
- Humans
- Immunohistochemistry
- Inflammation/metabolism
- Inflammation/pathology
- Inflammation/virology
- Liver Neoplasms/metabolism
- Liver Neoplasms/pathology
- Liver Neoplasms/virology
- RNA, Viral/analysis
- RNA, Viral/genetics
- Trans-Activators/genetics
- Trans-Activators/metabolism
- Viral Regulatory and Accessory Proteins
- fas Receptor/metabolism
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Affiliation(s)
- Y M Jin
- Department of Pathology, Ajou University School of Medicine, Suwon, Korea
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50
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Cao XY, Liu J, Lian ZR, Clayton M, Hu JL, Zhu MH, Fan DM, Feitelson M. Differentially expressed genes in hepatocellular carcinoma induced by woodchuck hepatitis B virus in mice. World J Gastroenterol 2001; 7:575-8. [PMID: 11819834 PMCID: PMC4688678 DOI: 10.3748/wjg.v7.i4.575] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Affiliation(s)
- X Y Cao
- Institute of Digestive Diseases, Xijing Hospital, Xi'an 710033, Shaanxi Province, China.
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