1
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Zhu P, Liu G, Wang X, Lu J, Zhou Y, Chen S, Gao Y, Wang C, Yu J, Sun Y, Zhou P. Transcription factor c-Jun modulates GLUT1 in glycolysis and breast cancer metastasis. BMC Cancer 2022; 22:1283. [PMID: 36476606 PMCID: PMC9730598 DOI: 10.1186/s12885-022-10393-x] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2022] [Accepted: 12/02/2022] [Indexed: 12/12/2022] Open
Abstract
As the main isoforms of membranous glucose transporters (GLUT), GLUT1 involves tumorigenesis, metastasis and prognosis in a variety of cancers. However, its role in breast cancer metastasis remains to be elucidated. Here we examined its transcriptional and survival data in patients with breast cancer from several independent databases including the Oncomine, Gene Expression Profiling Interactive Analysis, Gene Expression across Normal and Tumor tissue, UALCAN, cBioPortal, Kaplan-Meier Plotter and PROGgeneV2. We found that its mRNA expression was significantly high in cancer tissues, which was associated with metastasis and poor survival. Transcription factor c-Jun might bind to GLUT1 promoter to downregulate its gene expression or mRNA stability, therefore to suppress glycolysis and metastasis. By qRT-PCR, we verified that GLUT1 was significantly increased in 38 paired human breast cancer samples while JUN was decreased. Furthermore, the protein level of GLUT1 was higher in tumor than in normal tissues by IHC assay. To explore underlying pathways, we further performed GO and KEGG analysis of genes related to GLUT1 and JUN and found that GLUT1 was increased by transcription factor c-Jun in breast cancer tissues to influence glycolysis and breast cancer metastasis.
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Affiliation(s)
- Ping Zhu
- grid.8547.e0000 0001 0125 2443Department of Pathology and Musculoskeletal Oncology of Shanghai Cancer Center; Department of Physiology and Pathophysiology of School of Basic Medical Sciences, Fudan University, No. 270, 130 Dongan Road, Shanghai, 200032 China
| | - Guoping Liu
- grid.412987.10000 0004 0630 1330Department of General Surgery, Xin Hua Hospital Affiliated to Shanghai Jiao Tong University School of Medicine, Shanghai, 200092 People’s Republic of China
| | - Xue Wang
- grid.16821.3c0000 0004 0368 8293Department of Pathology, Ruijin Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, 200025 China
| | - Jingjing Lu
- grid.8547.e0000 0001 0125 2443Department of Pathology and Musculoskeletal Oncology of Shanghai Cancer Center; Department of Physiology and Pathophysiology of School of Basic Medical Sciences, Fudan University, No. 270, 130 Dongan Road, Shanghai, 200032 China
| | - Yue Zhou
- grid.8547.e0000 0001 0125 2443Department of Pathology and Musculoskeletal Oncology of Shanghai Cancer Center; Department of Physiology and Pathophysiology of School of Basic Medical Sciences, Fudan University, No. 270, 130 Dongan Road, Shanghai, 200032 China
| | - Shuyi Chen
- grid.8547.e0000 0001 0125 2443Department of Pathology and Musculoskeletal Oncology of Shanghai Cancer Center; Department of Physiology and Pathophysiology of School of Basic Medical Sciences, Fudan University, No. 270, 130 Dongan Road, Shanghai, 200032 China
| | - Yabiao Gao
- grid.8547.e0000 0001 0125 2443Department of Pathology and Musculoskeletal Oncology of Shanghai Cancer Center; Department of Physiology and Pathophysiology of School of Basic Medical Sciences, Fudan University, No. 270, 130 Dongan Road, Shanghai, 200032 China
| | - Chaofu Wang
- grid.16821.3c0000 0004 0368 8293Department of Pathology, Ruijin Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, 200025 China
| | - Jerry Yu
- grid.266623.50000 0001 2113 1622Department of Medicine, University of Louisville, Louisville, KY 40292 USA
| | - Yangbai Sun
- grid.8547.e0000 0001 0125 2443Department of Pathology and Musculoskeletal Oncology of Shanghai Cancer Center; Department of Physiology and Pathophysiology of School of Basic Medical Sciences, Fudan University, No. 270, 130 Dongan Road, Shanghai, 200032 China
| | - Ping Zhou
- grid.8547.e0000 0001 0125 2443Department of Pathology and Musculoskeletal Oncology of Shanghai Cancer Center; Department of Physiology and Pathophysiology of School of Basic Medical Sciences, Fudan University, No. 270, 130 Dongan Road, Shanghai, 200032 China
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2
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Li Y, Elmén L, Segota I, Xian Y, Tinoco R, Feng Y, Fujita Y, Segura Muñoz RR, Schmaltz R, Bradley LM, Ramer-Tait A, Zarecki R, Long T, Peterson SN, Ronai ZA. Prebiotic-Induced Anti-tumor Immunity Attenuates Tumor Growth. Cell Rep 2021; 30:1753-1766.e6. [PMID: 32049008 PMCID: PMC7053418 DOI: 10.1016/j.celrep.2020.01.035] [Citation(s) in RCA: 93] [Impact Index Per Article: 31.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2019] [Revised: 10/06/2019] [Accepted: 01/08/2020] [Indexed: 02/07/2023] Open
Abstract
Growing evidence supports the importance of gut microbiota in the control of tumor growth and response to therapy. Here, we select prebiotics that can enrich bacterial taxa that promote anti-tumor immunity. Addition of the prebiotics inulin or mucin to the diet of C57BL/6 mice induces anti-tumor immune responses and inhibition of BRAF mutant melanoma growth in a subcutaneously implanted syngeneic mouse model. Mucin fails to inhibit tumor growth in germ-free mice, indicating that the gut microbiota is required for the activation of the anti-tumor immune response. Inulin and mucin drive distinct changes in the microbiota, as inulin, but not mucin, limits tumor growth in syngeneic mouse models of colon cancer and NRAS mutant melanoma and enhances the efficacy of a MEK inhibitor against melanoma while delaying the emergence of drug resistance. We highlight the importance of gut microbiota in anti-tumor immunity and the potential therapeutic role for prebiotics in this process.
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Affiliation(s)
- Yan Li
- Sanford Burnham Prebys Medical Discovery Institute, La Jolla, CA 92037, USA
| | - Lisa Elmén
- Sanford Burnham Prebys Medical Discovery Institute, La Jolla, CA 92037, USA
| | - Igor Segota
- Sanford Burnham Prebys Medical Discovery Institute, La Jolla, CA 92037, USA
| | - Yibo Xian
- Department of Food Science and Technology, University of Nebraska-Lincoln, Lincoln, NE 68588, USA
| | - Roberto Tinoco
- Sanford Burnham Prebys Medical Discovery Institute, La Jolla, CA 92037, USA
| | - Yongmei Feng
- Sanford Burnham Prebys Medical Discovery Institute, La Jolla, CA 92037, USA
| | - Yu Fujita
- Sanford Burnham Prebys Medical Discovery Institute, La Jolla, CA 92037, USA
| | - Rafael R Segura Muñoz
- Department of Food Science and Technology, University of Nebraska-Lincoln, Lincoln, NE 68588, USA
| | - Robert Schmaltz
- Department of Food Science and Technology, University of Nebraska-Lincoln, Lincoln, NE 68588, USA
| | - Linda M Bradley
- Sanford Burnham Prebys Medical Discovery Institute, La Jolla, CA 92037, USA
| | - Amanda Ramer-Tait
- Department of Food Science and Technology, University of Nebraska-Lincoln, Lincoln, NE 68588, USA
| | - Raphy Zarecki
- Technion Integrated Cancer Center, Faculty of Medicine, Technion, Haifa 3525433, Israel
| | - Tao Long
- Sanford Burnham Prebys Medical Discovery Institute, La Jolla, CA 92037, USA
| | - Scott N Peterson
- Sanford Burnham Prebys Medical Discovery Institute, La Jolla, CA 92037, USA.
| | - Ze'ev A Ronai
- Sanford Burnham Prebys Medical Discovery Institute, La Jolla, CA 92037, USA.
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3
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Huebner K, Procházka J, Monteiro AC, Mahadevan V, Schneider-Stock R. The activating transcription factor 2: an influencer of cancer progression. Mutagenesis 2020; 34:375-389. [PMID: 31799611 PMCID: PMC6923166 DOI: 10.1093/mutage/gez041] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2019] [Accepted: 11/18/2019] [Indexed: 12/26/2022] Open
Abstract
In contrast to the continuous increase in survival rates for many cancer entities, colorectal cancer (CRC) and pancreatic cancer are predicted to be ranked among the top 3 cancer-related deaths in the European Union by 2025. Especially, fighting metastasis still constitutes an obstacle to be overcome in CRC and pancreatic cancer. As described by Fearon and Vogelstein, the development of CRC is based on sequential mutations leading to the activation of proto-oncogenes and the inactivation of tumour suppressor genes. In pancreatic cancer, genetic alterations also attribute to tumour development and progression. Recent findings have identified new potentially important transcription factors in CRC, among those the activating transcription factor 2 (ATF2). ATF2 is a basic leucine zipper protein and is involved in physiological and developmental processes, as well as in tumorigenesis. The mutation burden of ATF2 in CRC and pancreatic cancer is rather negligible; however, previous studies in other tumours indicated that ATF2 expression level and subcellular localisation impact tumour progression and patient prognosis. In a tissue- and stimulus-dependent manner, ATF2 is activated by upstream kinases, dimerises and induces target gene expression. Dependent on its dimerisation partner, ATF2 homodimers or heterodimers bind to cAMP-response elements or activator protein 1 consensus motifs. Pioneering work has been performed in melanoma in which the dual role of ATF2 is best understood. Even though there is increasing interest in ATF2 recently, only little is known about its involvement in CRC and pancreatic cancer. In this review, we summarise the current understanding of the underestimated ‘cancer gene chameleon’ ATF2 in apoptosis, epithelial-to-mesenchymal transition and microRNA regulation and highlight its functions in CRC and pancreatic cancer. We further provide a novel ATF2 3D structure with key phosphorylation sites and an updated overview of all so-far available mouse models to study ATF2 in vivo.
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Affiliation(s)
- Kerstin Huebner
- Experimental Tumorpathology, Institute of Pathology, University Hospital Erlangen, Friedrich-Alexander University Erlangen-Nuremberg, Erlangen, Germany
| | - Jan Procházka
- Czech Centre for Phenogenomics, Institute of Molecular Genetics of the ASCR, Prague, Czech Republic
| | - Ana C Monteiro
- Experimental Tumorpathology, Institute of Pathology, University Hospital Erlangen, Friedrich-Alexander University Erlangen-Nuremberg, Erlangen, Germany
| | - Vijayalakshmi Mahadevan
- Institute of Bioinformatics and Applied Biotechnology, Biotech Park, Electronic City Phase I, Bangalore, India
| | - Regine Schneider-Stock
- Experimental Tumorpathology, Institute of Pathology, University Hospital Erlangen, Friedrich-Alexander University Erlangen-Nuremberg, Erlangen, Germany
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4
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Pathria G, Lee JS, Hasnis E, Tandoc K, Scott DA, Verma S, Feng Y, Larue L, Sahu AD, Topisirovic I, Ruppin E, Ronai ZA. Translational reprogramming marks adaptation to asparagine restriction in cancer. Nat Cell Biol 2019; 21:1590-1603. [PMID: 31740775 PMCID: PMC7307327 DOI: 10.1038/s41556-019-0415-1] [Citation(s) in RCA: 52] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2019] [Accepted: 09/25/2019] [Indexed: 01/24/2023]
Abstract
While amino acid restriction remains an attractive strategy for cancer therapy, metabolic adaptations limit its effectiveness. Here we demonstrate a role of translational reprogramming in the survival of asparagine-restricted cancer cells. Asparagine limitation in melanoma and pancreatic cancer cells activates RTK-MAPK as part of a feedforward mechanism involving mTORC1-dependent increase in MNK1 and eIF4E, resulting in enhanced translation of ATF4 mRNA. MAPK inhibition attenuates translational induction of ATF4 and the expression of its target asparagine biosynthesis enzyme ASNS, sensitizing melanoma and pancreatic tumors to asparagine restriction, reflected in their growth inhibition. Correspondingly, low ASNS expression is among the top predictors of response to MAPK signaling inhibitors in melanoma patients and is associated with favorable prognosis, when combined with low MAPK signaling activity. While unveiling a previously unknown axis of adaptation to asparagine deprivation, these studies offer the rationale for clinical evaluation of MAPK inhibitors in combination with asparagine restriction approaches.
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Affiliation(s)
- Gaurav Pathria
- Tumor Initiation and Maintenance Program, Cancer Center, Sanford Burnham Prebys Medical Discovery Institute, La Jolla, CA, USA.
| | - Joo Sang Lee
- Cancer Data Science Lab (CDSL), National Cancer Institute, National Institute of Health, Bethesda, MD, USA.,Samsung Medical Center, Sungkyunkwan University School of Medicine, Suwon, Republic of Korea
| | - Erez Hasnis
- Tumor Initiation and Maintenance Program, Cancer Center, Sanford Burnham Prebys Medical Discovery Institute, La Jolla, CA, USA
| | - Kristofferson Tandoc
- Gerald Bronfman Department of Oncology, Lady Davis Institute, SMBD Jewish General Hospital, and Departments of Experimental Medicine and Biochemistry, McGill University, Montreal, Quebec, Canada
| | - David A Scott
- Tumor Initiation and Maintenance Program, Cancer Center, Sanford Burnham Prebys Medical Discovery Institute, La Jolla, CA, USA
| | - Sachin Verma
- Tumor Initiation and Maintenance Program, Cancer Center, Sanford Burnham Prebys Medical Discovery Institute, La Jolla, CA, USA
| | - Yongmei Feng
- Tumor Initiation and Maintenance Program, Cancer Center, Sanford Burnham Prebys Medical Discovery Institute, La Jolla, CA, USA
| | - Lionel Larue
- Normal and Pathological Development of Melanocytes, Institut Curie, PSL Research University, INSERM U1021, Orsay, France.,Universitê Paris-Sud and Université Paris-Saclay, CNRS UMR 3347, Orsay, France.,Equipe Labellisée Ligue Contre le Cancer, Orsay, France
| | - Avinash D Sahu
- Harvard School of Public Health and Massachusetts General Hospital, Boston, MA, USA
| | - Ivan Topisirovic
- Samsung Medical Center, Sungkyunkwan University School of Medicine, Suwon, Republic of Korea
| | - Eytan Ruppin
- Cancer Data Science Lab (CDSL), National Cancer Institute, National Institute of Health, Bethesda, MD, USA
| | - Ze'ev A Ronai
- Tumor Initiation and Maintenance Program, Cancer Center, Sanford Burnham Prebys Medical Discovery Institute, La Jolla, CA, USA.
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5
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Rsu1-dependent control of PTEN expression is regulated via ATF2 and cJun. J Cell Commun Signal 2019; 13:331-341. [PMID: 30680530 DOI: 10.1007/s12079-018-00504-4] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2018] [Accepted: 12/18/2018] [Indexed: 12/19/2022] Open
Abstract
The Rsu1 protein contributes to cell adhesion and migration via its association with the adaptor complex of Integrin linked kinase (ILK), PINCH, and Parvin (IPP), which binds to the cytoplasmic domain of β1 integrins joining integrins to the actin cytoskeleton. Rsu1 binding to PINCH in the IPP complex is required for EGF-induced adhesion, spreading and migration in MCF10A mammary epithelial cells. In addition, Rsu1 expression inhibits Jun kinase but is necessary for the activation of MKK4 and p38 Map kinase signaling essential for migration in MCF10A cells. The data reported here examines the links between MKK4-p38-ATF2 signaling and AKT regulation in MCF10A cells. Ectopic Rsu1 inhibited AKT1 phosphorylation while Rsu1 depletion induced AKT activation and AKT1 phosphorylation of MKK4 on serine 80, blocking MKK4 activity. Rsu1 depletion also reduced the RNA for lipid phosphatase PTEN thus implicating PTEN in modulating levels of activated AKT in these conditions. ChIP analysis of the PTEN promoter revealed that Rsu1 depletion prevented binding of ATF2 to a positive regulatory site in the PTEN promoter and the enhanced binding of cJun to a negatively regulatory PTEN promoter site. These results demonstrate a mechanism by which Rsu1 adhesion signaling alters the balance between MKK4-p38-ATF2 and cJun activation thus altering PTEN expression in MCF10A cells.
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6
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Kehl T, Schneider L, Schmidt F, Stöckel D, Gerstner N, Backes C, Meese E, Keller A, Schulz MH, Lenhof HP. RegulatorTrail: a web service for the identification of key transcriptional regulators. Nucleic Acids Res 2017; 45:W146-W153. [PMID: 28472408 PMCID: PMC5570139 DOI: 10.1093/nar/gkx350] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2017] [Revised: 04/07/2017] [Accepted: 04/20/2017] [Indexed: 12/14/2022] Open
Abstract
Transcriptional regulators such as transcription factors and chromatin modifiers play a central role in most biological processes. Alterations in their activities have been observed in many diseases, e.g. cancer. Hence, it is of utmost importance to evaluate and assess the effects of transcriptional regulators on natural and pathogenic processes. Here, we present RegulatorTrail, a web service that provides rich functionality for the identification and prioritization of key transcriptional regulators that have a strong impact on, e.g. pathological processes. RegulatorTrail offers eight methods that use regulator binding information in combination with transcriptomic or epigenomic data to infer the most influential regulators. Our web service not only provides an intuitive web interface, but also a well-documented RESTful API that allows for a straightforward integration into third-party workflows. The presented case studies highlight the capabilities of our web service and demonstrate its potential for the identification of influential regulators: we successfully identified regulators that might explain the increased malignancy in metastatic melanoma compared to primary tumors, as well as important regulators in macrophages. RegulatorTrail is freely accessible at: https://regulatortrail.bioinf.uni-sb.de/.
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Affiliation(s)
- Tim Kehl
- Center for Bioinformatics, Saarland Informatics Campus, Saarland University, 66123 Saarbrücken, Germany
| | - Lara Schneider
- Center for Bioinformatics, Saarland Informatics Campus, Saarland University, 66123 Saarbrücken, Germany
| | - Florian Schmidt
- Center for Bioinformatics, Saarland Informatics Campus, Saarland University, 66123 Saarbrücken, Germany
- Cluster of Excellence Multimodal Computing and Interaction, Saarland Informatics Campus, 66123 Saarland University, Saarbrücken, Germany
- Max Planck Institute for Informatics, Saarland Informatics Campus, 66123 Saarbrücken, Germany
| | - Daniel Stöckel
- Center for Bioinformatics, Saarland Informatics Campus, Saarland University, 66123 Saarbrücken, Germany
| | - Nico Gerstner
- Center for Bioinformatics, Saarland Informatics Campus, Saarland University, 66123 Saarbrücken, Germany
| | - Christina Backes
- Center for Bioinformatics, Saarland Informatics Campus, Saarland University, 66123 Saarbrücken, Germany
| | - Eckart Meese
- Center for Bioinformatics, Saarland Informatics Campus, Saarland University, 66123 Saarbrücken, Germany
- Human Genetics, Saarland University, 66421 Homburg, Germany
| | - Andreas Keller
- Center for Bioinformatics, Saarland Informatics Campus, Saarland University, 66123 Saarbrücken, Germany
| | - Marcel H Schulz
- Center for Bioinformatics, Saarland Informatics Campus, Saarland University, 66123 Saarbrücken, Germany
- Cluster of Excellence Multimodal Computing and Interaction, Saarland Informatics Campus, 66123 Saarland University, Saarbrücken, Germany
- Max Planck Institute for Informatics, Saarland Informatics Campus, 66123 Saarbrücken, Germany
| | - Hans-Peter Lenhof
- Center for Bioinformatics, Saarland Informatics Campus, Saarland University, 66123 Saarbrücken, Germany
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7
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Watson G, Ronai ZA, Lau E. ATF2, a paradigm of the multifaceted regulation of transcription factors in biology and disease. Pharmacol Res 2017; 119:347-357. [PMID: 28212892 PMCID: PMC5457671 DOI: 10.1016/j.phrs.2017.02.004] [Citation(s) in RCA: 93] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/22/2016] [Revised: 02/01/2017] [Accepted: 02/02/2017] [Indexed: 01/16/2023]
Abstract
Stringent transcriptional regulation is crucial for normal cellular biology and organismal development. Perturbations in the proper regulation of transcription factors can result in numerous pathologies, including cancer. Thus, understanding how transcription factors are regulated and how they are dysregulated in disease states is key to the therapeutic targeting of these factors and/or the pathways that they regulate. Activating transcription factor 2 (ATF2) has been studied in a number of developmental and pathological conditions. Recent findings have shed light on the transcriptional, post-transcriptional, and post-translational regulatory mechanisms that influence ATF2 function, and thus, the transcriptional programs coordinated by ATF2. Given our current knowledge of its multiple levels of regulation and function, ATF2 represents a paradigm for the mechanistic complexity that can regulate transcription factor function. Thus, increasing our understanding of the regulation and function of ATF2 will provide insights into fundamental regulatory mechanisms that influence how cells integrate extracellular and intracellular signals into a genomic response through transcription factors. Characterization of ATF2 dysfunction in the context of pathological conditions, particularly in cancer biology and response to therapy, will be important in understanding how pathways controlled by ATF2 or other transcription factors might be therapeutically exploited. In this review, we provide an overview of the currently known upstream regulators and downstream targets of ATF2.
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Affiliation(s)
- Gregory Watson
- Department of Tumor Biology and Program in Chemical Biology and Molecular Medicine, H. Lee Moffitt Cancer Center, Tampa, FL, USA
| | - Ze'ev A Ronai
- Tumor Initiation and Maintenance Program, Cancer Center, Sanford Burnham Prebys Medical Discovery Institute, La Jolla, CA, USA; Technion Integrated Cancer Center, Rappaport Faculty of Medicine, Technion, Haifa, 3109601, Israel
| | - Eric Lau
- Department of Tumor Biology and Program in Chemical Biology and Molecular Medicine, H. Lee Moffitt Cancer Center, Tampa, FL, USA.
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8
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Li Q, Gao WQ, Dai WY, Yu C, Zhu RY, Jin J. ATF2 translation is induced under chemotherapeutic drug-mediated cellular stress via an IRES-dependent mechanism in human hepatic cancer Bel7402 cells. Oncol Lett 2016; 12:4795-4802. [PMID: 28105187 DOI: 10.3892/ol.2016.5274] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2015] [Accepted: 08/09/2016] [Indexed: 12/16/2022] Open
Abstract
Activating transcription factor (ATF) 2 is a member of the ATF/cyclic AMP-responsive element binding protein family, which exhibits both oncogenic and tumor-suppressor functions. In our preliminary experiments, it was observed that the expression of the ATF2 protein was induced following treatment with adriamycin (ADR) and paclitaxel (PTX), which may be regulated by internal ribosome entry segment (IRES)-mediated translation. By constructing a bicistronic vector containing the ATF2 5'-untranslated region (UTR), it was demonstrated that the ATF2 5'-UTR contains an IRES and maps a 30-nucleotide (nt) sequence (from nt 299 to nt ~269), which was essential for the IRES activity. The ATF2 IRES activity exhibited significant variation in different cell lines. In addition, it was observed that ADR and PTX also induced ATF2 IRES activity in Bel7402 cells. The present study has demonstrated that ATF2 translation is initiated via IRES, which is upregulated by ADR and PTX, thus suggesting that the regulation of the IRES-dependent translation of ATF2 may be involved in effecting the cancer cell response to chemotherapeutic drugs-mediated cellular stress.
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Affiliation(s)
- Qi Li
- Laboratory of Molecular Pharmacology, School of Pharmaceutical Sciences, Jiangnan University, Wuxi, Jiangsu 214122, P.R. China
| | - Wen-Qing Gao
- Laboratory of Molecular Pharmacology, School of Pharmaceutical Sciences, Jiangnan University, Wuxi, Jiangsu 214122, P.R. China
| | - Wen-Yan Dai
- Laboratory of Molecular Pharmacology, School of Pharmaceutical Sciences, Jiangnan University, Wuxi, Jiangsu 214122, P.R. China
| | - Chuang Yu
- Laboratory of Molecular Pharmacology, School of Pharmaceutical Sciences, Jiangnan University, Wuxi, Jiangsu 214122, P.R. China
| | - Rui-Yu Zhu
- Laboratory of Molecular Pharmacology, School of Pharmaceutical Sciences, Jiangnan University, Wuxi, Jiangsu 214122, P.R. China
| | - Jian Jin
- Laboratory of Molecular Pharmacology, School of Pharmaceutical Sciences, Jiangnan University, Wuxi, Jiangsu 214122, P.R. China
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9
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Mantel PY, Hjelmqvist D, Walch M, Kharoubi-Hess S, Nilsson S, Ravel D, Ribeiro M, Grüring C, Ma S, Padmanabhan P, Trachtenberg A, Ankarklev J, Brancucci NM, Huttenhower C, Duraisingh MT, Ghiran I, Kuo WP, Filgueira L, Martinelli R, Marti M. Infected erythrocyte-derived extracellular vesicles alter vascular function via regulatory Ago2-miRNA complexes in malaria. Nat Commun 2016; 7:12727. [PMID: 27721445 PMCID: PMC5062468 DOI: 10.1038/ncomms12727] [Citation(s) in RCA: 171] [Impact Index Per Article: 21.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2015] [Accepted: 07/28/2016] [Indexed: 12/19/2022] Open
Abstract
Malaria remains one of the greatest public health challenges worldwide, particularly in sub-Saharan Africa. The clinical outcome of individuals infected with Plasmodium falciparum parasites depends on many factors including host systemic inflammatory responses, parasite sequestration in tissues and vascular dysfunction. Production of pro-inflammatory cytokines and chemokines promotes endothelial activation as well as recruitment and infiltration of inflammatory cells, which in turn triggers further endothelial cell activation and parasite sequestration. Inflammatory responses are triggered in part by bioactive parasite products such as hemozoin and infected red blood cell-derived extracellular vesicles (iRBC-derived EVs). Here we demonstrate that such EVs contain functional miRNA-Argonaute 2 complexes that are derived from the host RBC. Moreover, we show that EVs are efficiently internalized by endothelial cells, where the miRNA-Argonaute 2 complexes modulate target gene expression and barrier properties. Altogether, these findings provide a mechanistic link between EVs and vascular dysfunction during malaria infection.
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Affiliation(s)
- Pierre-Yves Mantel
- Department of Immunology and Infectious Diseases, Harvard T.H. Chan School of Public Health, Boston, Massachusetts 02115, USA.,Department of Medicine, Unit of Anatomy, University of Fribourg, 1700 Fribourg, Switzerland
| | - Daisy Hjelmqvist
- Department of Immunology and Infectious Diseases, Harvard T.H. Chan School of Public Health, Boston, Massachusetts 02115, USA
| | - Michael Walch
- Department of Medicine, Unit of Anatomy, University of Fribourg, 1700 Fribourg, Switzerland
| | - Solange Kharoubi-Hess
- Department of Medicine, Unit of Anatomy, University of Fribourg, 1700 Fribourg, Switzerland
| | - Sandra Nilsson
- Department of Immunology and Infectious Diseases, Harvard T.H. Chan School of Public Health, Boston, Massachusetts 02115, USA
| | - Deepali Ravel
- Department of Immunology and Infectious Diseases, Harvard T.H. Chan School of Public Health, Boston, Massachusetts 02115, USA
| | - Marina Ribeiro
- Department of Immunology and Infectious Diseases, Harvard T.H. Chan School of Public Health, Boston, Massachusetts 02115, USA
| | - Christof Grüring
- Department of Immunology and Infectious Diseases, Harvard T.H. Chan School of Public Health, Boston, Massachusetts 02115, USA
| | - Siyuan Ma
- Department of Biostatistics, Harvard T.H. Chan School of Public Health, Boston, Massachusetts 02115, USA
| | - Prasad Padmanabhan
- Department of Immunology and Infectious Diseases, Harvard T.H. Chan School of Public Health, Boston, Massachusetts 02115, USA
| | - Alexander Trachtenberg
- Harvard Catalyst Laboratory for Innovative Translational Technologies, Harvard Medical School, Boston, Massachusetts 02115, USA
| | - Johan Ankarklev
- Department of Immunology and Infectious Diseases, Harvard T.H. Chan School of Public Health, Boston, Massachusetts 02115, USA
| | - Nicolas M Brancucci
- Department of Immunology and Infectious Diseases, Harvard T.H. Chan School of Public Health, Boston, Massachusetts 02115, USA.,Wellcome Trust Center for Molecular Parasitology, University of Glasgow, Glasgow G12 8TA, UK
| | - Curtis Huttenhower
- Department of Biostatistics, Harvard T.H. Chan School of Public Health, Boston, Massachusetts 02115, USA
| | - Manoj T Duraisingh
- Department of Immunology and Infectious Diseases, Harvard T.H. Chan School of Public Health, Boston, Massachusetts 02115, USA
| | - Ionita Ghiran
- Division of Allergy and Infection, Beth Israel Deaconess Medical Center, Boston, Massachusetts 02115, USA
| | - Winston P Kuo
- Harvard Catalyst Laboratory for Innovative Translational Technologies, Harvard Medical School, Boston, Massachusetts 02115, USA.,Predicine, Inc., Hayward, California 94545, USA
| | - Luis Filgueira
- Department of Medicine, Unit of Anatomy, University of Fribourg, 1700 Fribourg, Switzerland
| | - Roberta Martinelli
- Center for Vascular Biology Research, Beth Israel Deaconess Medical Center, Boston, Massachusetts 02115, USA
| | - Matthias Marti
- Department of Immunology and Infectious Diseases, Harvard T.H. Chan School of Public Health, Boston, Massachusetts 02115, USA.,Wellcome Trust Center for Molecular Parasitology, University of Glasgow, Glasgow G12 8TA, UK
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10
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A Transcriptionally Inactive ATF2 Variant Drives Melanomagenesis. Cell Rep 2016; 15:1884-92. [PMID: 27210757 DOI: 10.1016/j.celrep.2016.04.072] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2015] [Revised: 03/15/2016] [Accepted: 04/19/2016] [Indexed: 11/20/2022] Open
Abstract
Melanoma is one of the most lethal cutaneous malignancies, characterized by chemoresistance and a striking propensity to metastasize. The transcription factor ATF2 elicits oncogenic activities in melanoma, and its inhibition attenuates melanoma development. Here, we show that expression of a transcriptionally inactive form of Atf2 (Atf2(Δ8,9)) promotes development of melanoma in mouse models. Atf2(Δ8,9)-driven tumors show enhanced pigmentation, immune infiltration, and metastatic propensity. Similar to mouse Atf2(Δ8,9), we have identified a transcriptionally inactive human ATF2 splice variant 5 (ATF2(SV5)) that enhances the growth and migration capacity of cultured melanoma cells and immortalized melanocytes. ATF2(SV5) expression is elevated in human melanoma specimens and is associated with poor prognosis. These findings point to an oncogenic function for ATF2 in melanoma development that appears to be independent of its transcriptional activity.
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You Z, Zhou Y, Guo Y, Chen W, Chen S, Wang X. Activating transcription factor 2 expression mediates cell proliferation and is associated with poor prognosis in human non-small cell lung carcinoma. Oncol Lett 2015; 11:760-766. [PMID: 26870280 DOI: 10.3892/ol.2015.3922] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2014] [Accepted: 08/20/2015] [Indexed: 12/22/2022] Open
Abstract
Activating transcription factor 2 (ATF2) is a member of the cAMP response element binding protein family that heterodimerizes and activates other transcription factors involved in stress and DNA damage responses, growth, differentiation and apoptosis. ATF2 has been investigated as a potential carcinogenic biomarker in certain types of cancer, such as melanoma. However, its function and clinical significance in non-small cell lung cancer (NSCLC) has not been well studied. Therefore, the present study aimed to analyze the association between ATF2/phosphorylated (p)-ATF2 expression and NSCLC malignant behavior, and discuss its clinical significance. Reverse transcription-quantitative polymerase chain reaction and western blotting were used to detect the expression of ATF2 in NSCLC cell lines and fresh NSCLC tissue samples. In addition, immunohistochemistry (IHC) was performed to identify the location and expression of ATF2 and p-ATF2 (threonine 71) in paraffin-embedded sections of NSCLC and adjacent normal tissue. The results demonstrated that ATF2 was markedly overexpressed in the NSCLC cells and significantly overexpressed in the fresh NSCLC tissues compared with the control cells and samples (86 paraffin-embedded tissue sections), respectively (P<0.01). Further data demonstrated that ATF2 expression levels were significantly increased in tumor tissues compared to normal tissues and ATF2 was located in the cytoplasm and nucleus. ATF2 expression was closely associated with adverse clinical characteristics such as TNM stage (P=0.002), tumor size (P=0.018) and metastasis (P=0.027). In addition, nuclear p-ATF2 staining was positive in 65/86 samples of NSCLC. Furthermore, the Kaplan-Meier analysis indicated that patients with high levels of ATF2 and p-ATF2 expression had a significantly shorter overall survival compared with patients exhibiting a low expression (P<0.01 and P<0.05, respectively). Subsequent in vitro experiments revealed that cell growth decreased following knockdown of ATF2 expression using RNA interference, indicating that ATF2 may suppress cell proliferation. Taken together, the results of the present study demonstrated that ATF2 and p-ATF2 were significantly overexpressed in NSCLC tissues, and ATF2 and p-ATF2 overexpression predicted significantly worse outcomes for patients with NSCLC.
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Affiliation(s)
- Zhenyu You
- Department of Oncology, First Affiliated Hospital of Nanchang University, Nanchang, Jiangxi 330006, P.R. China
| | - Yong Zhou
- Department of Pharmacy, Peking University, Beijing 100083, P.R. China
| | - Yuling Guo
- Department of Oncology, First Affiliated Hospital of Nanchang University, Nanchang, Jiangxi 330006, P.R. China
| | - Wenyan Chen
- Department of Oncology, First Affiliated Hospital of Nanchang University, Nanchang, Jiangxi 330006, P.R. China
| | - Shaoqing Chen
- Department of Oncology, First Affiliated Hospital of Nanchang University, Nanchang, Jiangxi 330006, P.R. China
| | - Xiaolang Wang
- Department of Oncology, First Affiliated Hospital of Nanchang University, Nanchang, Jiangxi 330006, P.R. China
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Hagiyama M, Yoneshige A, Inoue T, Sato Y, Mimae T, Okada M, Ito A. The intracellular domain of cell adhesion molecule 1 is present in emphysematous lungs and induces lung epithelial cell apoptosis. J Biomed Sci 2015; 22:67. [PMID: 26259600 PMCID: PMC4531499 DOI: 10.1186/s12929-015-0173-8] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2015] [Accepted: 07/30/2015] [Indexed: 12/20/2022] Open
Abstract
Background Pulmonary emphysema is characterized histologically by destruction of alveolar walls and enlargement of air spaces due to lung epithelial cell apoptosis. Cell adhesion molecule 1 (CADM1) is an immunoglobulin superfamily member expressed in lung epithelial cells. CADM1 generates a membrane-associated C-terminal fragment, αCTF, through A disintegrin- and metalloprotease-10-mediated ectodomain shedding, subsequently releasing the intracellular domain (ICD) through γ-secretase-mediated intramembrane shedding of αCTF. αCTF localizes to mitochondria and induces apoptosis in lung epithelial cells. αCTF contributes to the development and progression of emphysema as a consequence of increased CADM1 ectodomain shedding. The purpose of this study was to examine whether the ICD makes a similar contribution. Results The ICD was synthesized as a 51-amino acid peptide, and its mutant was synthesized by substituting seven amino acids and deleting two amino acids. These peptides were labeled with fluorescein isothiocyanate and were introduced into various cell lines. ICD peptide-derived fluorescence was well visualized in lung epithelial cells at the site of Mitotracker mitochondrial labeling, but was detected in locations other than mitochondria in other cell types. Mutant peptide-derived fluorescence was detected in locations other than mitochondria, even in lung epithelial cells. Terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling assays revealed that transduction of the ICD peptide increased the proportion of apoptotic cells 2- to 5-fold in the lung epithelial cell lines, whereas the mutant peptide did not. Abundance of the ICD was below the Western blot detection limit in emphysematous (n = 4) and control (n = 4) human lungs. However, the ICD was detected only in emphysematous lungs when it was immunoprecipitated with anti-CADM1 antibody (4/4 vs. 0/4, P = 0.029). Conclusions As the abundance of ICD molecules was sparse but present, increased CADM1 shedding appeared to contribute to the development of emphysema by generating αCTF and the ICD in lung epithelial cells. Electronic supplementary material The online version of this article (doi:10.1186/s12929-015-0173-8) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Man Hagiyama
- Department of Pathology, Faculty of Medicine, Kinki University, Osaka, 589-8511, Japan.
| | - Azusa Yoneshige
- Department of Pathology, Faculty of Medicine, Kinki University, Osaka, 589-8511, Japan.
| | - Takao Inoue
- Department of Pathology, Faculty of Medicine, Kinki University, Osaka, 589-8511, Japan.
| | - Yasufumi Sato
- Department of Pathology, Faculty of Medicine, Kinki University, Osaka, 589-8511, Japan.
| | - Takahiro Mimae
- Department of Surgical Oncology, Research Institute for Radiation Biology and Medicine, Hiroshima University, Hiroshima, Japan.
| | - Morihito Okada
- Department of Surgical Oncology, Research Institute for Radiation Biology and Medicine, Hiroshima University, Hiroshima, Japan.
| | - Akihiko Ito
- Department of Pathology, Faculty of Medicine, Kinki University, Osaka, 589-8511, Japan.
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Liu Z, Luo Q, Guo C. Bim and VDAC1 are hierarchically essential for mitochondrial ATF2 mediated cell death. Cancer Cell Int 2015; 15:34. [PMID: 25852302 PMCID: PMC4387661 DOI: 10.1186/s12935-015-0188-y] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2015] [Accepted: 03/20/2015] [Indexed: 01/20/2023] Open
Abstract
BACKGROUND ATF2 mediated cytochrome c release is the formation of a channel with some unknown factors larger than that of the individual proteins. BHS-only proteins (BH3s), such as Bim, could induce BAX and VDAC, forming a new channel. According to this facts, we can speculated that there is possible signal relationship with BH3s and ATF2, which is associated with mitochondrial-based death programs. METHODS The growth inhibitory effects of mitochondrial ATF2 were tested in cancer cell lines B16F10, A549, EG7, and LL2. Apoptosis was measured by flow cytometry. The effects of ATF2 and levels of apoptosis regulatory proteins were measured by Western blotting. The interaction of proteins were evaluated by immunoprecipitation analysis. The in vivo antitumor activity of mitochondrial ATF2 were tested in xenograft B16F10 models. RESULTS Genotoxic stress enabled mitochondrial ATF2 accumulation, perturbing the HK1-VDAC1 complex, increasing mitochondrial permeability, and promoting apoptosis. ATF2 inhibition strongly reduced the conformational activation of Bim, suggesting that Bim acts downstream of ATF2. Although Bim downregulation had no effect on ATF2 activation, Bim knockdown abolished VDAC1 activation; the failure of VDAC1 activation in Bim-depleted cells could be reversed by the BH3-only protein mimic ABT-737. We also demonstrate that silencing of ATF2 in B16F10 cells increases both the incidence and prevalence of tumor xenografts in vivo, whereas stably mitochondrial ATF2 transfection inhibited B16F10 tumor xenografts growth. CONCLUSIONS Altogether, these results show that ATF2 is a component of the apoptosis machinery that involves a hierarchical contribution of ATF2, Bim, and VDAC1. Our data offer new insight into the mechanism of mitochondrial ATF2 in mitochondrial apoptosis.
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Affiliation(s)
- Zhaoyun Liu
- Laboratory of Surgery, Children's Hospital of Chongqing Medical University, 136 Zhongshan 2nd Rd, Chongqing, 400014 P. R. China
| | - Qianfu Luo
- Laboratory of Surgery, Children's Hospital of Chongqing Medical University, 136 Zhongshan 2nd Rd, Chongqing, 400014 P. R. China
| | - Chunbao Guo
- Laboratory of Surgery, Children's Hospital of Chongqing Medical University, 136 Zhongshan 2nd Rd, Chongqing, 400014 P. R. China.,Ministry of Education Key Laboratory of Child Development and Disorders, Chongqing, P. R. China
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Tints K, Prink M, Neuman T, Palm K. LXXLL peptide converts transportan 10 to a potent inducer of apoptosis in breast cancer cells. Int J Mol Sci 2014; 15:5680-98. [PMID: 24705462 PMCID: PMC4013589 DOI: 10.3390/ijms15045680] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2014] [Revised: 03/18/2014] [Accepted: 03/24/2014] [Indexed: 12/15/2022] Open
Abstract
Degenerate expression of transcription coregulator proteins is observed in most human cancers. Therefore, in targeted anti-cancer therapy development, intervention at the level of cancer-specific transcription is of high interest. The steroid receptor coactivator-1 (SRC-1) is highly expressed in breast, endometrial, and prostate cancer. It is present in various transcription complexes, including those containing nuclear hormone receptors. We examined the effects of a peptide that contains the LXXLL-motif of the human SRC-1 nuclear receptor box 1 linked to the cell-penetrating transportan 10 (TP10), hereafter referred to as TP10-SRC1LXXLL, on proliferation and estrogen-mediated transcription of breast cancer cells in vitro. Our data show that TP10-SRC1LXXLL induced dose-dependent cell death of breast cancer cells, and that this effect was not affected by estrogen receptor (ER) status. Surprisingly TP10-SRC1LXXLL severely reduced the viability and proliferation of hormone-unresponsive breast cancer MDA-MB-231 cells. In addition, the regulation of the endogenous ERα direct target gene pS2 was not affected by TP10-SRC1LXXLL in estrogen-stimulated MCF-7 cells. Dermal fibroblasts were similarly affected by treatment with higher concentrations of TP10-SRC1LXXLL and this effect was significantly delayed. These results suggest that the TP10-SRC1LXXLL peptide may be an effective drug candidate in the treatment of cancers with minimal therapeutic options, for example ER-negative tumors.
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Affiliation(s)
- Kairit Tints
- Protobios LLC, Mäealuse 4, Tallinn 12618, Estonia.
| | - Madis Prink
- Protobios LLC, Mäealuse 4, Tallinn 12618, Estonia.
| | | | - Kaia Palm
- Protobios LLC, Mäealuse 4, Tallinn 12618, Estonia.
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Walluscheck D, Poehlmann A, Hartig R, Lendeckel U, Schönfeld P, Hotz-Wagenblatt A, Reissig K, Bajbouj K, Roessner A, Schneider-Stock R. ATF2 knockdown reinforces oxidative stress-induced apoptosis in TE7 cancer cells. J Cell Mol Med 2013; 17:976-88. [PMID: 23800081 PMCID: PMC3780530 DOI: 10.1111/jcmm.12071] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2012] [Accepted: 04/01/2013] [Indexed: 12/22/2022] Open
Abstract
Cancer cells showing low apoptotic effects following oxidative stress-induced DNA damage are mainly affected by growth arrest. Thus, recent studies focus on improving anti-cancer therapies by increasing apoptosis sensitivity. We aimed at identifying a universal molecule as potential target to enhance oxidative stress-based anti-cancer therapy through a switch from cell cycle arrest to apoptosis. A cDNA microarray was performed with hydrogen peroxide-treated oesophageal squamous epithelial cancer cells TE7. This cell line showed checkpoint activation via p21WAF1, but low apoptotic response following DNA damage. The potential target molecule was chosen depended on the following demands: it should regulate DNA damage response, cell cycle and apoptosis. As the transcription factor ATF2 is implicated in all these processes, we focused on this protein. We investigated checkpoint activation via ATF2. Indeed, ATF2 knockdown revealed ATF2-triggered p21WAF1 protein expression, suggesting p21WAF1 transactivation through ATF2. Using chromatin immunoprecipitation (ChIP), we identified a hitherto unknown ATF2-binding sequence in the p21WAF1 promoter. p-ATF2 was found to interact with p-c-Jun, creating the AP-1 complex. Moreover, ATF2 knockdown led to c-Jun downregulation. This suggests ATF2-driven induction of c-Jun expression, thereby enhancing ATF2 transcriptional activity via c-Jun-ATF2 heterodimerization. Notably, downregulation of ATF2 caused a switch from cell cycle arrest to reinforced apoptosis, presumably via p21WAF1 downregulation, confirming the importance of ATF2 in the establishment of cell cycle arrest. 1-Chloro-2,4-dinitrobenzene also led to ATF2-dependent G2/M arrest, suggesting that this is a general feature induced by oxidative stress. As ATF2 knockdown also increased apoptosis, we propose ATF2 as a target for combined oxidative stress-based anti-cancer therapies.
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Affiliation(s)
- Diana Walluscheck
- Department of Pathology, Otto-von-Guericke University, Magdeburg, Germany
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Varsano T, Lau E, Feng Y, Garrido M, Milan L, Heynen-Genel S, Hassig CA, Ronai ZA. Inhibition of melanoma growth by small molecules that promote the mitochondrial localization of ATF2. Clin Cancer Res 2013; 19:2710-22. [PMID: 23589174 DOI: 10.1158/1078-0432.ccr-12-2689] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
PURPOSE Effective therapy for malignant melanoma, the leading cause of death from skin cancer, remains an area of significant unmet need in oncology. The elevated expression of PKCε in advanced metastatic melanoma results in the increased phosphorylation of the transcription factor ATF2 on threonine 52, which causes its nuclear localization and confers its oncogenic activities. The nuclear-to-mitochondrial translocation of ATF2 following genotoxic stress promotes apoptosis, a function that is largely lost in melanoma cells, due to its confined nuclear localization. Therefore, promoting the nuclear export of ATF2, which sensitizes melanoma cells to apoptosis, represents a novel therapeutic modality. EXPERIMENTAL DESIGN We conducted a pilot high-throughput screen of 3,800 compounds to identify small molecules that promote melanoma cell death by inducing the cytoplasmic localization of ATF2. The imaging-based ATF2 translocation assay was conducted using UACC903 melanoma cells that stably express doxycycline-inducible GFP-ATF2. RESULTS We identified two compounds (SBI-0089410 and SBI-0087702) that promoted the cytoplasmic localization of ATF2, reduced cell viability, inhibited colony formation, cell motility, and anchorage-free growth, and increased mitochondrial membrane permeability. SBI-0089410 inhibited the 12-O-tetradecanoylphorbol-l3-acetate (TPA)-induced membrane translocation of protein kinase C (PKC) isoforms, whereas both compounds decreased ATF2 phosphorylation by PKCε and ATF2 transcriptional activity. Overexpression of either constitutively active PKCε or phosphomimic mutant ATF2(T52E) attenuated the cellular effects of the compounds. CONCLUSION The imaging-based high-throughput screen provides a proof-of-concept for the identification of small molecules that block the oncogenic addiction to PKCε signaling by promoting ATF2 nuclear export, resulting in mitochondrial membrane leakage and melanoma cell death.
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Affiliation(s)
- Tal Varsano
- Signal Transduction Program, Sanford-Burnham Medical Research Institute, La Jolla, California 92037, USA
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Abstract
Melanoma is often considered one of the most aggressive and treatment-resistant human cancers. It is a disease that, due to the presence of melanin pigment, was accurately diagnosed earlier than most other malignancies and that has been subjected to countless therapeutic strategies. Aside from early surgical resection, no therapeutic modality has been found to afford a high likelihood of curative outcome. However, discoveries reported in recent years have revealed a near avalanche of breakthroughs in the melanoma field-breakthroughs that span fundamental understanding of the molecular basis of the disease all the way to new therapeutic strategies that produce unquestionable clinical benefit. These discoveries have been born from the successful fruits of numerous researchers working in many-sometimes-related, although also distinct-biomedical disciplines. Discoveries of frequent mutations involving BRAF(V600E), developmental and oncogenic roles for the microphthalmia-associated transcription factor (MITF) pathway, clinical efficacy of BRAF-targeted small molecules, and emerging mechanisms underlying resistance to targeted therapeutics represent just a sample of the findings that have created a striking inflection in the quest for clinically meaningful progress in the melanoma field.
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Affiliation(s)
- Hensin Tsao
- Department of Dermatology, Massachusetts General Hospital, Boston, Massachusetts 02114, USA
- The Wellman Center for Photomedicine, Boston, Massachusetts 02114, USA
| | - Lynda Chin
- Department of Genomic Medicine, University of Texas MD Anderson Cancer Center, Houston, Texas 77030, USA
| | - Levi A. Garraway
- Department of Medical Oncology, Dana Farber Cancer Institute, Boston, Massachusetts 02115, USA
| | - David E. Fisher
- Department of Dermatology, Massachusetts General Hospital, Boston, Massachusetts 02114, USA
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Lau E, Kluger H, Varsano T, Lee K, Scheffler I, Rimm DL, Ideker T, Ronai ZA. PKCε promotes oncogenic functions of ATF2 in the nucleus while blocking its apoptotic function at mitochondria. Cell 2012; 148:543-55. [PMID: 22304920 DOI: 10.1016/j.cell.2012.01.016] [Citation(s) in RCA: 61] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2011] [Revised: 08/12/2011] [Accepted: 01/06/2012] [Indexed: 01/05/2023]
Abstract
The transcription factor ATF2 elicits oncogenic activities in melanoma and tumor suppressor activities in nonmalignant skin cancer. Here, we identify that ATF2 tumor suppressor function is determined by its ability to localize at the mitochondria, where it alters membrane permeability following genotoxic stress. The ability of ATF2 to reach the mitochondria is determined by PKCε, which directs ATF2 nuclear localization. Genotoxic stress attenuates PKCε effect on ATF2; enables ATF2 nuclear export and localization at the mitochondria, where it perturbs the HK1-VDAC1 complex; increases mitochondrial permeability; and promotes apoptosis. Significantly, high levels of PKCε, as seen in melanoma cells, block ATF2 nuclear export and function at the mitochondria, thereby attenuating apoptosis following exposure to genotoxic stress. In melanoma tumor samples, high PKCε levels associate with poor prognosis. Overall, our findings provide the framework for understanding how subcellular localization enables ATF2 oncogenic or tumor suppressor functions.
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Affiliation(s)
- Eric Lau
- Signal Transduction Program, Sanford-Burnham Medical Research Institute, La Jolla, CA 92037, USA
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Diring J, Camuzeaux B, Donzeau M, Vigneron M, Rosa-Calatrava M, Kedinger C, Chatton B. A cytoplasmic negative regulator isoform of ATF7 impairs ATF7 and ATF2 phosphorylation and transcriptional activity. PLoS One 2011; 6:e23351. [PMID: 21858082 PMCID: PMC3156760 DOI: 10.1371/journal.pone.0023351] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2011] [Accepted: 07/13/2011] [Indexed: 11/18/2022] Open
Abstract
Alternative splicing and post-translational modifications are processes that give rise to the complexity of the proteome. The nuclear ATF7 and ATF2 (activating transcription factor) are structurally homologous leucine zipper transcription factors encoded by distinct genes. Stress and growth factors activate ATF2 and ATF7 mainly via sequential phosphorylation of two conserved threonine residues in their activation domain. Distinct protein kinases, among which mitogen-activated protein kinases (MAPK), phosphorylate ATF2 and ATF7 first on Thr71/Thr53 and next on Thr69/Thr51 residues respectively, resulting in transcriptional activation. Here, we identify and characterize a cytoplasmic alternatively spliced isoform of ATF7. This variant, named ATF7-4, inhibits both ATF2 and ATF7 transcriptional activities by impairing the first phosphorylation event on Thr71/Thr53 residues. ATF7-4 indeed sequesters the Thr53-phosphorylating kinase in the cytoplasm. Upon stimulus-induced phosphorylation, ATF7-4 is poly-ubiquitinated and degraded, enabling the release of the kinase and ATF7/ATF2 activation. Our data therefore conclusively establish that ATF7-4 is an important cytoplasmic negative regulator of ATF7 and ATF2 transcription factors.
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Affiliation(s)
- Jessica Diring
- Université de Strasbourg, UMR7242 Biotechnologie et Signalisation Cellulaire, Ecole Supérieure de Biotechnologie de Strasbourg, BP10413, Illkirch, France
| | - Barbara Camuzeaux
- Université de Strasbourg, UMR7242 Biotechnologie et Signalisation Cellulaire, Ecole Supérieure de Biotechnologie de Strasbourg, BP10413, Illkirch, France
| | - Mariel Donzeau
- Université de Strasbourg, UMR7242 Biotechnologie et Signalisation Cellulaire, Ecole Supérieure de Biotechnologie de Strasbourg, BP10413, Illkirch, France
| | - Marc Vigneron
- Université de Strasbourg, UMR7242 Biotechnologie et Signalisation Cellulaire, Ecole Supérieure de Biotechnologie de Strasbourg, BP10413, Illkirch, France
| | - Manuel Rosa-Calatrava
- Laboratoire de Virologie et Pathologie Humaine VirPath, Université Claude Bernard Lyon 1, Hospices Civils de Lyon, Lyon, France
| | - Claude Kedinger
- Université de Strasbourg, UMR7242 Biotechnologie et Signalisation Cellulaire, Ecole Supérieure de Biotechnologie de Strasbourg, BP10413, Illkirch, France
| | - Bruno Chatton
- Université de Strasbourg, UMR7242 Biotechnologie et Signalisation Cellulaire, Ecole Supérieure de Biotechnologie de Strasbourg, BP10413, Illkirch, France
- * E-mail:
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Hamsa TP, Kuttan G. Harmine activates intrinsic and extrinsic pathways of apoptosis in B16F-10 melanoma. Chin Med 2011; 6:11. [PMID: 21429205 PMCID: PMC3076298 DOI: 10.1186/1749-8546-6-11] [Citation(s) in RCA: 57] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2010] [Accepted: 03/23/2011] [Indexed: 12/22/2022] Open
Abstract
Background Harmine is a beta-carboline alkaloid from the plant Peganum harmala. Previous studies found that harmine inhibited metastasis of B16F-10 melanoma cells. This study aims to elucidate the role of harmine in apoptosis of B16F-10 cells. Methods B16F-10 melanoma cells were treated in the presence and absence of harmine in vitro. Morphological changes, cell cycle and expression of various pro and anti- apoptotic genes were analyzed for the study of apoptosis. Results Morphological observation and DNA laddering assay showed that harmine treated cells displayed marked apoptotic characteristics, such as nuclear fragmentation, appearance of apoptotic bodies and DNA laddering fragment. TUNEL assay and flow cytometric analysis also confirmed apoptosis. Furthermore, RT-PCR analysis showed that harmine induced apoptosis in B16F-10 melanoma cells by up-regulating Bax and activating Caspase-3, 9 and p53 and down-regulating Bcl-2. Harmine also up-regulated Caspase-8 and Bid, indicating that harmine affected both extrinsic and intrinsic pathways of apoptosis. This study also showed inhibitory effects of harmine on some transcription factors and pro- inflammatory cytokines that protect cell from apoptosis. Conclusion Harmine activates both intrinsic and extrinsic pathways of apoptosis and regulates some transcription factors and pro-inflammatory cytokines.
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Duffey D, Dolgilevich S, Razzouk S, Li L, Green R, Gorti GK. Activating transcription factor-2 in survival mechanisms in head and neck carcinoma cells. Head Neck 2010; 33:1586-99. [PMID: 21990224 DOI: 10.1002/hed.21648] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2010] [Revised: 09/08/2010] [Accepted: 09/14/2010] [Indexed: 12/12/2022] Open
Abstract
BACKGROUND Activating transcription factor-2 (ATF2) is associated with tumor progression but is not well studied in head and neck squamous cell carcinoma (HNSCC). Its effects in stress and its importance in other survival mechanisms were studied. METHODS ATF2 expression and nuclear activation were confirmed in HNSCC. After modulation of ATF2, in vitro effects on proliferation and chemosensitivity were studied. Effects on in vivo tumor growth and interleukin 8 (IL-8) expression were determined. Tumor necrosis factor-alpha (TNF-α) treatment was used to further evaluate cytokine production and chemosensitivity. RESULTS Reductions of ATF2 resulted in significant nuclear p-ATF2 activation, cisplatin resistance, and augmented IL-8 expression without affecting in vivo tumor growth. In this setting, TNF increases p-p38 phosphorylation and chemosensitivity while further enhancing IL-8 production. CONCLUSION Our data suggest regulatory roles for ATF2 in TNF-related mechanisms of HNSCC. Its perturbation and nuclear activation are associated with significant effects on survival and cytokine production.
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Affiliation(s)
- Dianne Duffey
- Yale University School of Medicine Section of Otolaryngology, 333 Cedar St, Box 208041, New Haven, Connecticut 06520, USA.
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Shah M, Bhoumik A, Goel V, Dewing A, Breitwieser W, Kluger H, Krajewski S, Krajewska M, DeHart J, Lau E, Kallenberg DM, Jeong H, Eroshkin A, Bennett DC, Chin L, Bosenberg M, Jones N, Ronai ZA. A role for ATF2 in regulating MITF and melanoma development. PLoS Genet 2010; 6:e1001258. [PMID: 21203491 PMCID: PMC3009656 DOI: 10.1371/journal.pgen.1001258] [Citation(s) in RCA: 56] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2010] [Accepted: 11/22/2010] [Indexed: 11/19/2022] Open
Abstract
The transcription factor ATF2 has been shown to attenuate melanoma susceptibility to apoptosis and to promote its ability to form tumors in xenograft models. To directly assess ATF2's role in melanoma development, we crossed a mouse melanoma model (Nras(Q61K)::Ink4a⁻/⁻) with mice expressing a transcriptionally inactive form of ATF2 in melanocytes. In contrast to 7/21 of the Nras(Q61K)::Ink4a⁻/⁻ mice, only 1/21 mice expressing mutant ATF2 in melanocytes developed melanoma. Gene expression profiling identified higher MITF expression in primary melanocytes expressing transcriptionally inactive ATF2. MITF downregulation by ATF2 was confirmed in the skin of Atf2⁻/⁻ mice, in primary human melanocytes, and in 50% of human melanoma cell lines. Inhibition of MITF transcription by MITF was shown to be mediated by ATF2-JunB-dependent suppression of SOX10 transcription. Remarkably, oncogenic BRAF (V600E)-dependent focus formation of melanocytes on soft agar was inhibited by ATF2 knockdown and partially rescued upon shMITF co-expression. On melanoma tissue microarrays, a high nuclear ATF2 to MITF ratio in primary specimens was associated with metastatic disease and poor prognosis. Our findings establish the importance of transcriptionally active ATF2 in melanoma development through fine-tuning of MITF expression.
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Affiliation(s)
- Meera Shah
- Sanford-Burnham Medical Research Institute, La Jolla, California, United States of America
| | - Anindita Bhoumik
- Sanford-Burnham Medical Research Institute, La Jolla, California, United States of America
| | - Vikas Goel
- Sanford-Burnham Medical Research Institute, La Jolla, California, United States of America
| | - Antimone Dewing
- Sanford-Burnham Medical Research Institute, La Jolla, California, United States of America
| | - Wolfgang Breitwieser
- Paterson Institute for Cancer Research, University of Manchester, Manchester, United Kingdom
| | - Harriet Kluger
- Department of Medicine, Yale University, New Haven, Connecticut, United States of America
| | - Stan Krajewski
- Sanford-Burnham Medical Research Institute, La Jolla, California, United States of America
| | - Maryla Krajewska
- Sanford-Burnham Medical Research Institute, La Jolla, California, United States of America
| | - Jason DeHart
- Sanford-Burnham Medical Research Institute, La Jolla, California, United States of America
| | - Eric Lau
- Sanford-Burnham Medical Research Institute, La Jolla, California, United States of America
| | - David M. Kallenberg
- Basic Medical Sciences, St. George's, University of London, London, United Kingdom
| | - Hyeongnam Jeong
- Department of Medical Oncology, Dana-Farber Cancer Institute, Boston, Massachusetts, United States of America
| | - Alexey Eroshkin
- Sanford-Burnham Medical Research Institute, La Jolla, California, United States of America
| | - Dorothy C. Bennett
- Basic Medical Sciences, St. George's, University of London, London, United Kingdom
| | - Lynda Chin
- Department of Medical Oncology, Dana-Farber Cancer Institute, Boston, Massachusetts, United States of America
| | - Marcus Bosenberg
- Department of Pathology Yale University, New Haven, Connecticut, United States of America
| | - Nic Jones
- Paterson Institute for Cancer Research, University of Manchester, Manchester, United Kingdom
| | - Ze'ev A. Ronai
- Sanford-Burnham Medical Research Institute, La Jolla, California, United States of America
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23
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Ara AI, Xia M, Ramani K, Mato JM, Lu SC. S-adenosylmethionine inhibits lipopolysaccharide-induced gene expression via modulation of histone methylation. Hepatology 2008; 47:1655-66. [PMID: 18393372 PMCID: PMC2408693 DOI: 10.1002/hep.22231] [Citation(s) in RCA: 77] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
UNLABELLED We previously showed that S-adenosylmethionine (SAMe) and its metabolite methylthioadenosine (MTA) blocked lipopolysaccharide (LPS)-induced tumor necrosis factor alpha (TNFalpha) expression in RAW (murine macrophage cell line) and Kupffer cells at the transcriptional level without affecting nuclear factor kappa B nuclear binding. However, the exact molecular mechanism or mechanisms of the inhibitory effect were unclear. While SAMe is a methyl donor, MTA is an inhibitor of methylation. SAMe can convert to MTA spontaneously, so the effect of exogenous SAMe may be mediated by MTA. The aim of our current work is to examine whether the mechanism of SAMe and MTA's inhibitory effect on proinflammatory mediators might involve modulation of histone methylation. In RAW cells, we found that LPS induced TNFalpha expression by both transcriptional and posttranscriptional mechanisms. SAMe and MTA treatment inhibited the LPS-induced increase in gene transcription. Using the chromatin immunoprecipitation assay, we found that LPS increased the binding of trimethylated histone 3 lysine 4 (H3K4) to the TNFalpha promoter, and this was completely blocked by either SAMe or MTA pretreatment. Similar effects were observed with LPS-mediated induction of inducible nitric oxide synthase (iNOS). LPS increased the binding of histone methyltransferases Set1 and myeloid/lymphoid leukemia to these promoters, which was unaffected by SAMe or MTA. The effects of MTA in RAW cells were confirmed in vivo in LPS-treated mice. Exogenous SAMe is unstable and converts spontaneously to MTA, which is stable and cell-permeant. Treatment with SAMe doubled intracellular MTA and S-adenosylhomocysteine (SAH) levels. SAH also inhibited H3K4 binding to TNFalpha and iNOS promoters. CONCLUSION The mechanism of SAMe's pharmacologic inhibitory effect on proinflammatory mediators is mainly mediated by MTA and SAH at the level of histone methylation.
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Affiliation(s)
- Ainhoa Iglesias Ara
- Division of Gastroenterology and Liver Diseases, University of Southern California Research Center for Liver Diseases, University of Southern California–University of California at Los Angeles Research Center for Alcoholic Liver and Pancreatic Diseases, Keck School of Medicine of the University of Southern California, Los Angeles, CA
| | - Meng Xia
- Division of Gastroenterology and Liver Diseases, University of Southern California Research Center for Liver Diseases, University of Southern California–University of California at Los Angeles Research Center for Alcoholic Liver and Pancreatic Diseases, Keck School of Medicine of the University of Southern California, Los Angeles, CA
| | - Komal Ramani
- Division of Gastroenterology and Liver Diseases, University of Southern California Research Center for Liver Diseases, University of Southern California–University of California at Los Angeles Research Center for Alcoholic Liver and Pancreatic Diseases, Keck School of Medicine of the University of Southern California, Los Angeles, CA
| | - José M. Mato
- Centro de Investigación Cooperativa en Biociencias, Centro de Investigación Biomédica en Red de Enfermedades Hepáticas y Digestivas, Technology Park of Bizkaia, Derio, Bizkaia, Spain
| | - Shelly C. Lu
- Division of Gastroenterology and Liver Diseases, University of Southern California Research Center for Liver Diseases, University of Southern California–University of California at Los Angeles Research Center for Alcoholic Liver and Pancreatic Diseases, Keck School of Medicine of the University of Southern California, Los Angeles, CA
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24
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Bhoumik A, Singha N, O'Connell MJ, Ronai ZA. Regulation of TIP60 by ATF2 modulates ATM activation. J Biol Chem 2008; 283:17605-14. [PMID: 18397884 DOI: 10.1074/jbc.m802030200] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023] Open
Abstract
TIP60 (HTATIP) is a histone acetyltransferase (HAT) whose function is critical in regulating ataxia-telangiectasia mutated (ATM) activation, gene expression, and chromatin acetylation in DNA repair. Here we show that under non-stressed conditions, activating transcription factor-2 (ATF2) in cooperation with Cul3 ubiquitin ligase promotes degradation of TIP60, thereby attenuating its HAT activity. Inhibiting either ATF2 or Cul3 expression by small interfering RNA stabilizes the TIP60 protein. ATF2 association with TIP60 on chromatin is decreased following exposure to ionizing radiation (IR), resulting in enhanced TIP60 stability and activity. We also identified a panel of melanoma and prostate cancer cell lines whose ATF2 expression is inversely correlated with TIP60 levels and ATM activation after IR. Inhibition of ATF2 expression in these lines restored TIP60 protein levels and both basal and IR-induced levels of ATM activity. Our study provides novel insight into regulation of ATM activation by ATF2-dependent control of TIP60 stability and activity.
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Affiliation(s)
- Anindita Bhoumik
- Signal Transduction Program, Burnham Institute for Medical Research, La Jolla, California 92037, USA
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25
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Huang Y, Minigh J, Miles S, Niles RM. Retinoic acid decreases ATF-2 phosphorylation and sensitizes melanoma cells to taxol-mediated growth inhibition. J Mol Signal 2008; 3:3. [PMID: 18269766 PMCID: PMC2265711 DOI: 10.1186/1750-2187-3-3] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2007] [Accepted: 02/12/2008] [Indexed: 12/30/2022] Open
Abstract
Cutaneous melanoma is often resistant to chemo- and radiotherapy. This resistance has recently been demonstrated to be due, at least in part, to high activating transcription factor 2 (ATF-2) activity in these tumors. In concordance with these reports, we found that B16 mouse melanoma cells had higher levels of ATF-2 than immortalized, but non-malignant mouse melanocytes. In addition, the melanoma cells had a much higher amount of phosphorylated (active) ATF-2 than the immortalized melanocytes. In the course of determining how retinoic acid (RA) stimulates activating protein-1 (AP-1) activity in B16 melanoma, we discovered that this retinoid decreased the phosphorylation of ATF-2. It appears that this effect is mediated through p38 MAPK, because RA decreased p38 phosphorylation, and a selective inhibitor of p38 MAPK (SB203580) also inhibited the phosphorylation of ATF-2. Since ATF-2 activity appears to be involved in resistance of melanoma to chemotherapy, we tested the hypothesis that treatment of the melanoma cells with RA would sensitize them to the growth-inhibitory effect of taxol. We found that pretreatment of B16 cells with RA decreased the IC50 from 50 nM to 1 nM taxol. On the basis of these findings and our previous work on AP-1, we propose a model in which treatment of B16 cells with RA decreases the phosphorylation of ATF-2, which results in less dimer formation with Jun. The "freed-up" Jun can then form a heterodimer with Fos, resulting in the increased AP-1 activity observed in RA-treated B16 cells. Shifting the balance from predominantly ATF-2:Jun dimers to a higher amount of Jun:Fos dimers could lead a change in target gene expression that reduces resistance to chemotherapeutic drugs and contributes to the pathway by which RA arrests proliferation and induces differentiation.
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Affiliation(s)
- Ying Huang
- Department of Biochemistry and Microbiology, Joan C, Edwards School of Medicine, Marshall University, One John Marshall Drive - BBSC, Huntington, WV, 25755, USA.
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26
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Bhoumik A, Fichtman B, DeRossi C, Breitwieser W, Kluger HM, Davis S, Subtil A, Meltzer P, Krajewski S, Jones N, Ronai Z. Suppressor role of activating transcription factor 2 (ATF2) in skin cancer. Proc Natl Acad Sci U S A 2008; 105:1674-9. [PMID: 18227516 PMCID: PMC2234203 DOI: 10.1073/pnas.0706057105] [Citation(s) in RCA: 65] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2007] [Indexed: 11/18/2022] Open
Abstract
Activating transcription factor 2 (ATF2) regulates transcription in response to stress and growth factor stimuli. Here, we use a mouse model in which ATF2 was selectively deleted in keratinocytes. Crossing the conditionally expressed ATF2 mutant with K14-Cre mice (K14.ATF2(f/f)) resulted in selective expression of mutant ATF2 within the basal layer of the epidermis. When subjected to a two-stage skin carcinogenesis protocol [7,12-dimethylbenz[a]anthracene/phorbol 12-tetradecanoate 13-acetate (DMBA/TPA)], K14.ATF2(f/f) mice showed significant increases in both the incidence and prevalence of papilloma development compared with the WT ATF2 mice. Consistent with these findings, keratinocytes of K14.ATF2(f/f) mice exhibit greater anchorage-independent growth compared with ATF2 WT keratinocytes. Papillomas of K14.ATF2(f/f) mice exhibit reduced expression of presenilin1, which is associated with enhanced beta-catenin and cyclin D1, and reduced Notch1 expression. Significantly, a reduction of nuclear ATF2 and increased beta-catenin expression were seen in samples of squamous and basal cell carcinoma, as opposed to normal skin. Our data reveal that loss of ATF2 transcriptional activity serves to promote skin tumor formation, thereby indicating a suppressor activity of ATF2 in skin tumor formation.
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Affiliation(s)
| | - Boris Fichtman
- *Burnham Institute for Medical Research, La Jolla, CA 92037
| | | | - Wolfgang Breitwieser
- Paterson Institute for Cancer Research, University of Manchester, Manchester M20 4BX, United Kingdom
| | | | - Sean Davis
- Genetics Branch, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892
| | - Antonio Subtil
- Dermatology, Yale University School of Medicine, New Haven, CT 06520; and
| | - Paul Meltzer
- Genetics Branch, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892
| | - Stan Krajewski
- *Burnham Institute for Medical Research, La Jolla, CA 92037
| | - Nic Jones
- Paterson Institute for Cancer Research, University of Manchester, Manchester M20 4BX, United Kingdom
| | - Ze'ev Ronai
- *Burnham Institute for Medical Research, La Jolla, CA 92037
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27
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Abbas S, Bhoumik A, Dahl R, Vasile S, Krajewski S, Cosford NDP, Ronai ZA. Preclinical studies of celastrol and acetyl isogambogic acid in melanoma. Clin Cancer Res 2008; 13:6769-78. [PMID: 18006779 DOI: 10.1158/1078-0432.ccr-07-1536] [Citation(s) in RCA: 76] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
PURPOSE Sensitize melanomas to apoptosis and inhibit their growth and metastatic potential by compounds that mimic the activities of activating transcription factor 2 (ATF2)-driven peptides. EXPERIMENTAL DESIGN Small-molecule chemical library consisting of 3,280 compounds was screened to identify compounds that elicit properties identified for ATF2 peptide, including (a) sensitization of melanoma cells to apoptosis, (b) inhibition of ATF2 transcriptional activity, (c) activation of c-Jun NH(2)-terminal kinase (JNK) and c-Jun transcriptional activity, and (d) inhibition of melanoma growth and metastasis in mouse models. RESULTS Two compounds, celastrol (CSL) and acetyl isogambogic acid, could, within a low micromolar range, efficiently elicit cell death in melanoma cells. Both compounds efficiently inhibit ATF2 transcriptional activities, activate JNK, and increase c-Jun transcriptional activities. Similar to the ATF2 peptide, both compounds require JNK activity for their ability to inhibit melanoma cell viability. Derivatives of CSL were identified as potent inducers of cell death in mouse and human melanomas. CSL and a derivative (CA19) could also efficiently inhibit growth of human and mouse melanoma tumors and reduce the number of lung metastases in syngeneic and xenograft mouse models. CONCLUSIONS These studies show for the first time the effect of CSL and acetyl isogambogic acid on melanoma. These compounds elicit activities that resemble the well-characterized ATF2 peptide and may therefore offer new approaches for the treatment of this tumor type.
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Affiliation(s)
- Sabiha Abbas
- Signal Transduction Program, Cancer Center, Burnham Institute for Medical Research, 10901 North Torrey Pines Road, La Jolla, CA 92037, USA
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28
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Bhoumik A, Lopez-Bergami P, Ronai Z. ATF2 on the double - activating transcription factor and DNA damage response protein. ACTA ACUST UNITED AC 2008; 20:498-506. [PMID: 17935492 DOI: 10.1111/j.1600-0749.2007.00414.x] [Citation(s) in RCA: 68] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Signal transduction pathways play a key role in the regulation of key cellular processes, including survival and death. Growing evidence points to changes in signaling pathway that occur during skin tumor development and progression. Such changes impact the activity of downstream substrates, including transcription factors. The activating transcription factor 2 (ATF2) has been implicated in malignant and non-malignant skin tumor developments. ATF2 mediates both transcription and DNA damage control, through its phosphorylation by JNK/p38 or ATM/ATR respectively. Here, we summarize our present understanding of ATF2 regulation, function and contribution to malignant and non-malignant skin tumor development.
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Affiliation(s)
- Anindita Bhoumik
- Signal Transduction Program, Burnham Institute for Medical Research, La Jolla, CA, USA
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29
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Abstract
Understanding regulatory pathways involved in melanoma development and progression has advanced significantly in recent years. It is now appreciated that melanoma is the result of complex changes in multiple signaling pathways that affect growth control, metabolism, motility and the ability to escape cell death programs. Here we review the major signaling pathways currently known to be deregulated in melanoma with an implication to its development and progression. Among these pathways are Ras, B-Raf, MEK, PTEN, phosphatidylinositol-3 kinase (PI3Ks) and Akt which are constitutively activated in a significant number of melanoma tumors, in most cases due to genomic change. Other pathways discussed in this review include the [Janus kinase/signal transducer and activator of transcription (JAK/STAT), transforming growth factor-beta pathways which are also activated in melanoma, although the underlying mechanism is not yet clear. As a paradigm for remodeled signaling pathways, melanoma also offers a unique opportunity for targeted drug development.
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Affiliation(s)
- Pablo Lopez-Bergami
- Signal Transduction Program, Burnham Institute for Medical Research, La Jolla, CA, USA
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30
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Govindarajan B, Sligh JE, Vincent BJ, Li M, Canter JA, Nickoloff BJ, Rodenburg RJ, Smeitink JA, Oberley L, Zhang Y, Slingerland J, Arnold RS, Lambeth JD, Cohen C, Hilenski L, Griendling K, Martínez-Diez M, Cuezva JM, Arbiser JL. Overexpression of Akt converts radial growth melanoma to vertical growth melanoma. J Clin Invest 2007; 117:719-29. [PMID: 17318262 PMCID: PMC1797605 DOI: 10.1172/jci30102] [Citation(s) in RCA: 221] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2006] [Accepted: 12/12/2006] [Indexed: 12/17/2022] Open
Abstract
Melanoma is the cancer with the highest increase in incidence, and transformation of radial growth to vertical growth (i.e., noninvasive to invasive) melanoma is required for invasive disease and metastasis. We have previously shown that p42/p44 MAP kinase is activated in radial growth melanoma, suggesting that further signaling events are required for vertical growth melanoma. The molecular events that accompany this transformation are not well understood. Akt, a signaling molecule downstream of PI3K, was introduced into the radial growth WM35 melanoma in order to test whether Akt overexpression is sufficient to accomplish this transformation. Overexpression of Akt led to upregulation of VEGF, increased production of superoxide ROS, and the switch to a more pronounced glycolytic metabolism. Subcutaneous implantation of WM35 cells overexpressing Akt led to rapidly growing tumors in vivo, while vector control cells did not form tumors. We demonstrated that Akt was associated with malignant transformation of melanoma through at least 2 mechanisms. First, Akt may stabilize cells with extensive mitochondrial DNA mutation, which can generate ROS. Second, Akt can induce expression of the ROS-generating enzyme NOX4. Akt thus serves as a molecular switch that increases angiogenesis and the generation of superoxide, fostering more aggressive tumor behavior. Targeting Akt and ROS may be of therapeutic importance in treatment of advanced melanoma.
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Affiliation(s)
- Baskaran Govindarajan
- Department of Dermatology, Emory University School of Medicine, and Atlanta Veterans Administration Medical Center, Atlanta, Georgia, USA.
Division of Dermatology and Center for Human Genetics Research, Vanderbilt University Medical Center and VA Tennessee Valley Healthcare System, Nashville, Tennessee, USA.
Cardinal Bernardin Cancer Center, Loyola University Health System, Chicago, Illinois, USA.
Nijmegen Centre for Mitochondrial Disorders, Department of Paediatrics, Radboud University Medical Centre Nijmegen, Nijmegen, The Netherlands.
Free Radical and Radiation Biology Program, Department of Radiation Oncology, University of Iowa, Iowa City, Iowa, USA.
Department of Medicine, University of Miami Leonard M. Miller School of Medicine, Miami, Florida, USA.
Department of Pathology and Laboratory Medicine and
Department of Medicine, Division of Cardiology, Emory University School of Medicine, Atlanta, Georgia, USA.
Departamento de Biología Molecular, Centro de Biología Molecular Severo Ochoa, Universidad Autónoma de Madrid, Madrid, Spain
| | - James E. Sligh
- Department of Dermatology, Emory University School of Medicine, and Atlanta Veterans Administration Medical Center, Atlanta, Georgia, USA.
Division of Dermatology and Center for Human Genetics Research, Vanderbilt University Medical Center and VA Tennessee Valley Healthcare System, Nashville, Tennessee, USA.
Cardinal Bernardin Cancer Center, Loyola University Health System, Chicago, Illinois, USA.
Nijmegen Centre for Mitochondrial Disorders, Department of Paediatrics, Radboud University Medical Centre Nijmegen, Nijmegen, The Netherlands.
Free Radical and Radiation Biology Program, Department of Radiation Oncology, University of Iowa, Iowa City, Iowa, USA.
Department of Medicine, University of Miami Leonard M. Miller School of Medicine, Miami, Florida, USA.
Department of Pathology and Laboratory Medicine and
Department of Medicine, Division of Cardiology, Emory University School of Medicine, Atlanta, Georgia, USA.
Departamento de Biología Molecular, Centro de Biología Molecular Severo Ochoa, Universidad Autónoma de Madrid, Madrid, Spain
| | - Bethaney J. Vincent
- Department of Dermatology, Emory University School of Medicine, and Atlanta Veterans Administration Medical Center, Atlanta, Georgia, USA.
Division of Dermatology and Center for Human Genetics Research, Vanderbilt University Medical Center and VA Tennessee Valley Healthcare System, Nashville, Tennessee, USA.
Cardinal Bernardin Cancer Center, Loyola University Health System, Chicago, Illinois, USA.
Nijmegen Centre for Mitochondrial Disorders, Department of Paediatrics, Radboud University Medical Centre Nijmegen, Nijmegen, The Netherlands.
Free Radical and Radiation Biology Program, Department of Radiation Oncology, University of Iowa, Iowa City, Iowa, USA.
Department of Medicine, University of Miami Leonard M. Miller School of Medicine, Miami, Florida, USA.
Department of Pathology and Laboratory Medicine and
Department of Medicine, Division of Cardiology, Emory University School of Medicine, Atlanta, Georgia, USA.
Departamento de Biología Molecular, Centro de Biología Molecular Severo Ochoa, Universidad Autónoma de Madrid, Madrid, Spain
| | - Meiling Li
- Department of Dermatology, Emory University School of Medicine, and Atlanta Veterans Administration Medical Center, Atlanta, Georgia, USA.
Division of Dermatology and Center for Human Genetics Research, Vanderbilt University Medical Center and VA Tennessee Valley Healthcare System, Nashville, Tennessee, USA.
Cardinal Bernardin Cancer Center, Loyola University Health System, Chicago, Illinois, USA.
Nijmegen Centre for Mitochondrial Disorders, Department of Paediatrics, Radboud University Medical Centre Nijmegen, Nijmegen, The Netherlands.
Free Radical and Radiation Biology Program, Department of Radiation Oncology, University of Iowa, Iowa City, Iowa, USA.
Department of Medicine, University of Miami Leonard M. Miller School of Medicine, Miami, Florida, USA.
Department of Pathology and Laboratory Medicine and
Department of Medicine, Division of Cardiology, Emory University School of Medicine, Atlanta, Georgia, USA.
Departamento de Biología Molecular, Centro de Biología Molecular Severo Ochoa, Universidad Autónoma de Madrid, Madrid, Spain
| | - Jeffrey A. Canter
- Department of Dermatology, Emory University School of Medicine, and Atlanta Veterans Administration Medical Center, Atlanta, Georgia, USA.
Division of Dermatology and Center for Human Genetics Research, Vanderbilt University Medical Center and VA Tennessee Valley Healthcare System, Nashville, Tennessee, USA.
Cardinal Bernardin Cancer Center, Loyola University Health System, Chicago, Illinois, USA.
Nijmegen Centre for Mitochondrial Disorders, Department of Paediatrics, Radboud University Medical Centre Nijmegen, Nijmegen, The Netherlands.
Free Radical and Radiation Biology Program, Department of Radiation Oncology, University of Iowa, Iowa City, Iowa, USA.
Department of Medicine, University of Miami Leonard M. Miller School of Medicine, Miami, Florida, USA.
Department of Pathology and Laboratory Medicine and
Department of Medicine, Division of Cardiology, Emory University School of Medicine, Atlanta, Georgia, USA.
Departamento de Biología Molecular, Centro de Biología Molecular Severo Ochoa, Universidad Autónoma de Madrid, Madrid, Spain
| | - Brian J. Nickoloff
- Department of Dermatology, Emory University School of Medicine, and Atlanta Veterans Administration Medical Center, Atlanta, Georgia, USA.
Division of Dermatology and Center for Human Genetics Research, Vanderbilt University Medical Center and VA Tennessee Valley Healthcare System, Nashville, Tennessee, USA.
Cardinal Bernardin Cancer Center, Loyola University Health System, Chicago, Illinois, USA.
Nijmegen Centre for Mitochondrial Disorders, Department of Paediatrics, Radboud University Medical Centre Nijmegen, Nijmegen, The Netherlands.
Free Radical and Radiation Biology Program, Department of Radiation Oncology, University of Iowa, Iowa City, Iowa, USA.
Department of Medicine, University of Miami Leonard M. Miller School of Medicine, Miami, Florida, USA.
Department of Pathology and Laboratory Medicine and
Department of Medicine, Division of Cardiology, Emory University School of Medicine, Atlanta, Georgia, USA.
Departamento de Biología Molecular, Centro de Biología Molecular Severo Ochoa, Universidad Autónoma de Madrid, Madrid, Spain
| | - Richard J. Rodenburg
- Department of Dermatology, Emory University School of Medicine, and Atlanta Veterans Administration Medical Center, Atlanta, Georgia, USA.
Division of Dermatology and Center for Human Genetics Research, Vanderbilt University Medical Center and VA Tennessee Valley Healthcare System, Nashville, Tennessee, USA.
Cardinal Bernardin Cancer Center, Loyola University Health System, Chicago, Illinois, USA.
Nijmegen Centre for Mitochondrial Disorders, Department of Paediatrics, Radboud University Medical Centre Nijmegen, Nijmegen, The Netherlands.
Free Radical and Radiation Biology Program, Department of Radiation Oncology, University of Iowa, Iowa City, Iowa, USA.
Department of Medicine, University of Miami Leonard M. Miller School of Medicine, Miami, Florida, USA.
Department of Pathology and Laboratory Medicine and
Department of Medicine, Division of Cardiology, Emory University School of Medicine, Atlanta, Georgia, USA.
Departamento de Biología Molecular, Centro de Biología Molecular Severo Ochoa, Universidad Autónoma de Madrid, Madrid, Spain
| | - Jan A. Smeitink
- Department of Dermatology, Emory University School of Medicine, and Atlanta Veterans Administration Medical Center, Atlanta, Georgia, USA.
Division of Dermatology and Center for Human Genetics Research, Vanderbilt University Medical Center and VA Tennessee Valley Healthcare System, Nashville, Tennessee, USA.
Cardinal Bernardin Cancer Center, Loyola University Health System, Chicago, Illinois, USA.
Nijmegen Centre for Mitochondrial Disorders, Department of Paediatrics, Radboud University Medical Centre Nijmegen, Nijmegen, The Netherlands.
Free Radical and Radiation Biology Program, Department of Radiation Oncology, University of Iowa, Iowa City, Iowa, USA.
Department of Medicine, University of Miami Leonard M. Miller School of Medicine, Miami, Florida, USA.
Department of Pathology and Laboratory Medicine and
Department of Medicine, Division of Cardiology, Emory University School of Medicine, Atlanta, Georgia, USA.
Departamento de Biología Molecular, Centro de Biología Molecular Severo Ochoa, Universidad Autónoma de Madrid, Madrid, Spain
| | - Larry Oberley
- Department of Dermatology, Emory University School of Medicine, and Atlanta Veterans Administration Medical Center, Atlanta, Georgia, USA.
Division of Dermatology and Center for Human Genetics Research, Vanderbilt University Medical Center and VA Tennessee Valley Healthcare System, Nashville, Tennessee, USA.
Cardinal Bernardin Cancer Center, Loyola University Health System, Chicago, Illinois, USA.
Nijmegen Centre for Mitochondrial Disorders, Department of Paediatrics, Radboud University Medical Centre Nijmegen, Nijmegen, The Netherlands.
Free Radical and Radiation Biology Program, Department of Radiation Oncology, University of Iowa, Iowa City, Iowa, USA.
Department of Medicine, University of Miami Leonard M. Miller School of Medicine, Miami, Florida, USA.
Department of Pathology and Laboratory Medicine and
Department of Medicine, Division of Cardiology, Emory University School of Medicine, Atlanta, Georgia, USA.
Departamento de Biología Molecular, Centro de Biología Molecular Severo Ochoa, Universidad Autónoma de Madrid, Madrid, Spain
| | - Yuping Zhang
- Department of Dermatology, Emory University School of Medicine, and Atlanta Veterans Administration Medical Center, Atlanta, Georgia, USA.
Division of Dermatology and Center for Human Genetics Research, Vanderbilt University Medical Center and VA Tennessee Valley Healthcare System, Nashville, Tennessee, USA.
Cardinal Bernardin Cancer Center, Loyola University Health System, Chicago, Illinois, USA.
Nijmegen Centre for Mitochondrial Disorders, Department of Paediatrics, Radboud University Medical Centre Nijmegen, Nijmegen, The Netherlands.
Free Radical and Radiation Biology Program, Department of Radiation Oncology, University of Iowa, Iowa City, Iowa, USA.
Department of Medicine, University of Miami Leonard M. Miller School of Medicine, Miami, Florida, USA.
Department of Pathology and Laboratory Medicine and
Department of Medicine, Division of Cardiology, Emory University School of Medicine, Atlanta, Georgia, USA.
Departamento de Biología Molecular, Centro de Biología Molecular Severo Ochoa, Universidad Autónoma de Madrid, Madrid, Spain
| | - Joyce Slingerland
- Department of Dermatology, Emory University School of Medicine, and Atlanta Veterans Administration Medical Center, Atlanta, Georgia, USA.
Division of Dermatology and Center for Human Genetics Research, Vanderbilt University Medical Center and VA Tennessee Valley Healthcare System, Nashville, Tennessee, USA.
Cardinal Bernardin Cancer Center, Loyola University Health System, Chicago, Illinois, USA.
Nijmegen Centre for Mitochondrial Disorders, Department of Paediatrics, Radboud University Medical Centre Nijmegen, Nijmegen, The Netherlands.
Free Radical and Radiation Biology Program, Department of Radiation Oncology, University of Iowa, Iowa City, Iowa, USA.
Department of Medicine, University of Miami Leonard M. Miller School of Medicine, Miami, Florida, USA.
Department of Pathology and Laboratory Medicine and
Department of Medicine, Division of Cardiology, Emory University School of Medicine, Atlanta, Georgia, USA.
Departamento de Biología Molecular, Centro de Biología Molecular Severo Ochoa, Universidad Autónoma de Madrid, Madrid, Spain
| | - Rebecca S. Arnold
- Department of Dermatology, Emory University School of Medicine, and Atlanta Veterans Administration Medical Center, Atlanta, Georgia, USA.
Division of Dermatology and Center for Human Genetics Research, Vanderbilt University Medical Center and VA Tennessee Valley Healthcare System, Nashville, Tennessee, USA.
Cardinal Bernardin Cancer Center, Loyola University Health System, Chicago, Illinois, USA.
Nijmegen Centre for Mitochondrial Disorders, Department of Paediatrics, Radboud University Medical Centre Nijmegen, Nijmegen, The Netherlands.
Free Radical and Radiation Biology Program, Department of Radiation Oncology, University of Iowa, Iowa City, Iowa, USA.
Department of Medicine, University of Miami Leonard M. Miller School of Medicine, Miami, Florida, USA.
Department of Pathology and Laboratory Medicine and
Department of Medicine, Division of Cardiology, Emory University School of Medicine, Atlanta, Georgia, USA.
Departamento de Biología Molecular, Centro de Biología Molecular Severo Ochoa, Universidad Autónoma de Madrid, Madrid, Spain
| | - J. David Lambeth
- Department of Dermatology, Emory University School of Medicine, and Atlanta Veterans Administration Medical Center, Atlanta, Georgia, USA.
Division of Dermatology and Center for Human Genetics Research, Vanderbilt University Medical Center and VA Tennessee Valley Healthcare System, Nashville, Tennessee, USA.
Cardinal Bernardin Cancer Center, Loyola University Health System, Chicago, Illinois, USA.
Nijmegen Centre for Mitochondrial Disorders, Department of Paediatrics, Radboud University Medical Centre Nijmegen, Nijmegen, The Netherlands.
Free Radical and Radiation Biology Program, Department of Radiation Oncology, University of Iowa, Iowa City, Iowa, USA.
Department of Medicine, University of Miami Leonard M. Miller School of Medicine, Miami, Florida, USA.
Department of Pathology and Laboratory Medicine and
Department of Medicine, Division of Cardiology, Emory University School of Medicine, Atlanta, Georgia, USA.
Departamento de Biología Molecular, Centro de Biología Molecular Severo Ochoa, Universidad Autónoma de Madrid, Madrid, Spain
| | - Cynthia Cohen
- Department of Dermatology, Emory University School of Medicine, and Atlanta Veterans Administration Medical Center, Atlanta, Georgia, USA.
Division of Dermatology and Center for Human Genetics Research, Vanderbilt University Medical Center and VA Tennessee Valley Healthcare System, Nashville, Tennessee, USA.
Cardinal Bernardin Cancer Center, Loyola University Health System, Chicago, Illinois, USA.
Nijmegen Centre for Mitochondrial Disorders, Department of Paediatrics, Radboud University Medical Centre Nijmegen, Nijmegen, The Netherlands.
Free Radical and Radiation Biology Program, Department of Radiation Oncology, University of Iowa, Iowa City, Iowa, USA.
Department of Medicine, University of Miami Leonard M. Miller School of Medicine, Miami, Florida, USA.
Department of Pathology and Laboratory Medicine and
Department of Medicine, Division of Cardiology, Emory University School of Medicine, Atlanta, Georgia, USA.
Departamento de Biología Molecular, Centro de Biología Molecular Severo Ochoa, Universidad Autónoma de Madrid, Madrid, Spain
| | - Lu Hilenski
- Department of Dermatology, Emory University School of Medicine, and Atlanta Veterans Administration Medical Center, Atlanta, Georgia, USA.
Division of Dermatology and Center for Human Genetics Research, Vanderbilt University Medical Center and VA Tennessee Valley Healthcare System, Nashville, Tennessee, USA.
Cardinal Bernardin Cancer Center, Loyola University Health System, Chicago, Illinois, USA.
Nijmegen Centre for Mitochondrial Disorders, Department of Paediatrics, Radboud University Medical Centre Nijmegen, Nijmegen, The Netherlands.
Free Radical and Radiation Biology Program, Department of Radiation Oncology, University of Iowa, Iowa City, Iowa, USA.
Department of Medicine, University of Miami Leonard M. Miller School of Medicine, Miami, Florida, USA.
Department of Pathology and Laboratory Medicine and
Department of Medicine, Division of Cardiology, Emory University School of Medicine, Atlanta, Georgia, USA.
Departamento de Biología Molecular, Centro de Biología Molecular Severo Ochoa, Universidad Autónoma de Madrid, Madrid, Spain
| | - Kathy Griendling
- Department of Dermatology, Emory University School of Medicine, and Atlanta Veterans Administration Medical Center, Atlanta, Georgia, USA.
Division of Dermatology and Center for Human Genetics Research, Vanderbilt University Medical Center and VA Tennessee Valley Healthcare System, Nashville, Tennessee, USA.
Cardinal Bernardin Cancer Center, Loyola University Health System, Chicago, Illinois, USA.
Nijmegen Centre for Mitochondrial Disorders, Department of Paediatrics, Radboud University Medical Centre Nijmegen, Nijmegen, The Netherlands.
Free Radical and Radiation Biology Program, Department of Radiation Oncology, University of Iowa, Iowa City, Iowa, USA.
Department of Medicine, University of Miami Leonard M. Miller School of Medicine, Miami, Florida, USA.
Department of Pathology and Laboratory Medicine and
Department of Medicine, Division of Cardiology, Emory University School of Medicine, Atlanta, Georgia, USA.
Departamento de Biología Molecular, Centro de Biología Molecular Severo Ochoa, Universidad Autónoma de Madrid, Madrid, Spain
| | - Marta Martínez-Diez
- Department of Dermatology, Emory University School of Medicine, and Atlanta Veterans Administration Medical Center, Atlanta, Georgia, USA.
Division of Dermatology and Center for Human Genetics Research, Vanderbilt University Medical Center and VA Tennessee Valley Healthcare System, Nashville, Tennessee, USA.
Cardinal Bernardin Cancer Center, Loyola University Health System, Chicago, Illinois, USA.
Nijmegen Centre for Mitochondrial Disorders, Department of Paediatrics, Radboud University Medical Centre Nijmegen, Nijmegen, The Netherlands.
Free Radical and Radiation Biology Program, Department of Radiation Oncology, University of Iowa, Iowa City, Iowa, USA.
Department of Medicine, University of Miami Leonard M. Miller School of Medicine, Miami, Florida, USA.
Department of Pathology and Laboratory Medicine and
Department of Medicine, Division of Cardiology, Emory University School of Medicine, Atlanta, Georgia, USA.
Departamento de Biología Molecular, Centro de Biología Molecular Severo Ochoa, Universidad Autónoma de Madrid, Madrid, Spain
| | - José M. Cuezva
- Department of Dermatology, Emory University School of Medicine, and Atlanta Veterans Administration Medical Center, Atlanta, Georgia, USA.
Division of Dermatology and Center for Human Genetics Research, Vanderbilt University Medical Center and VA Tennessee Valley Healthcare System, Nashville, Tennessee, USA.
Cardinal Bernardin Cancer Center, Loyola University Health System, Chicago, Illinois, USA.
Nijmegen Centre for Mitochondrial Disorders, Department of Paediatrics, Radboud University Medical Centre Nijmegen, Nijmegen, The Netherlands.
Free Radical and Radiation Biology Program, Department of Radiation Oncology, University of Iowa, Iowa City, Iowa, USA.
Department of Medicine, University of Miami Leonard M. Miller School of Medicine, Miami, Florida, USA.
Department of Pathology and Laboratory Medicine and
Department of Medicine, Division of Cardiology, Emory University School of Medicine, Atlanta, Georgia, USA.
Departamento de Biología Molecular, Centro de Biología Molecular Severo Ochoa, Universidad Autónoma de Madrid, Madrid, Spain
| | - Jack L. Arbiser
- Department of Dermatology, Emory University School of Medicine, and Atlanta Veterans Administration Medical Center, Atlanta, Georgia, USA.
Division of Dermatology and Center for Human Genetics Research, Vanderbilt University Medical Center and VA Tennessee Valley Healthcare System, Nashville, Tennessee, USA.
Cardinal Bernardin Cancer Center, Loyola University Health System, Chicago, Illinois, USA.
Nijmegen Centre for Mitochondrial Disorders, Department of Paediatrics, Radboud University Medical Centre Nijmegen, Nijmegen, The Netherlands.
Free Radical and Radiation Biology Program, Department of Radiation Oncology, University of Iowa, Iowa City, Iowa, USA.
Department of Medicine, University of Miami Leonard M. Miller School of Medicine, Miami, Florida, USA.
Department of Pathology and Laboratory Medicine and
Department of Medicine, Division of Cardiology, Emory University School of Medicine, Atlanta, Georgia, USA.
Departamento de Biología Molecular, Centro de Biología Molecular Severo Ochoa, Universidad Autónoma de Madrid, Madrid, Spain
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Bogoyevitch MA, Kobe B. Uses for JNK: the many and varied substrates of the c-Jun N-terminal kinases. Microbiol Mol Biol Rev 2006; 70:1061-95. [PMID: 17158707 PMCID: PMC1698509 DOI: 10.1128/mmbr.00025-06] [Citation(s) in RCA: 439] [Impact Index Per Article: 24.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
The c-Jun N-terminal kinases (JNKs) are members of a larger group of serine/threonine (Ser/Thr) protein kinases from the mitogen-activated protein kinase family. JNKs were originally identified as stress-activated protein kinases in the livers of cycloheximide-challenged rats. Their subsequent purification, cloning, and naming as JNKs have emphasized their ability to phosphorylate and activate the transcription factor c-Jun. Studies of c-Jun and related transcription factor substrates have provided clues about both the preferred substrate phosphorylation sequences and additional docking domains recognized by JNK. There are now more than 50 proteins shown to be substrates for JNK. These include a range of nuclear substrates, including transcription factors and nuclear hormone receptors, heterogeneous nuclear ribonucleoprotein K, and the Pol I-specific transcription factor TIF-IA, which regulates ribosome synthesis. Many nonnuclear substrates have also been characterized, and these are involved in protein degradation (e.g., the E3 ligase Itch), signal transduction (e.g., adaptor and scaffold proteins and protein kinases), apoptotic cell death (e.g., mitochondrial Bcl2 family members), and cell movement (e.g., paxillin, DCX, microtubule-associated proteins, the stathmin family member SCG10, and the intermediate filament protein keratin 8). The range of JNK actions in the cell is therefore likely to be complex. Further characterization of the substrates of JNK should provide clearer explanations of the intracellular actions of the JNKs and may allow new avenues for targeting the JNK pathways with therapeutic agents downstream of JNK itself.
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Affiliation(s)
- Marie A Bogoyevitch
- Cell Signalling Laboratory, Biochemistry and Molecular Biology (M310), School of Biomedical, Biomolecular and Chemical Sciences, University of Western Australia, 35 Stirling Highway, Crawley, Western Australia 6009, Australia.
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Ivanov VN, Hei TK. Sodium arsenite accelerates TRAIL-mediated apoptosis in melanoma cells through upregulation of TRAIL-R1/R2 surface levels and downregulation of cFLIP expression. Exp Cell Res 2006; 312:4120-38. [PMID: 17070520 PMCID: PMC1839882 DOI: 10.1016/j.yexcr.2006.09.019] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2006] [Revised: 08/23/2006] [Accepted: 09/13/2006] [Indexed: 12/22/2022]
Abstract
AP-1/cJun, NF-kappaB and STAT3 transcription factors control expression of numerous genes, which regulate critical cell functions including proliferation, survival and apoptosis. Sodium arsenite is known to suppress both the IKK-NF-kappaB and JAK2-STAT3 signaling pathways and to activate the MAPK/JNK-cJun pathways, thereby committing some cancers to undergo apoptosis. Indeed, sodium arsenite is an effective drug for the treatment of acute promyelocytic leukemia with little nonspecific toxicity. Malignant melanoma is highly refractory to conventional radio- and chemotherapy. In the present study, we observed strong effects of sodium arsenite treatment on upregulation of TRAIL-mediated apoptosis in human and mouse melanomas. Arsenite treatment upregulated surface levels of death receptors, TRAIL-R1 and TRAIL-R2, through increased translocation of these proteins from cytoplasm to the cell surface. Furthermore, activation of cJun and suppression of NF-kappaB by sodium arsenite resulted in upregulation of the endogenous TRAIL and downregulation of the cFLIP gene expression (which encodes one of the main anti-apoptotic proteins in melanomas) followed by cFLIP protein degradation and, finally, by acceleration of TRAIL-induced apoptosis. Direct suppression of cFLIP expression by cFLIP RNAi also accelerated TRAIL-induced apoptosis in these melanomas, while COX-2 suppression substantially increased levels of both TRAIL-induced and arsenite-induced apoptosis. In contrast, overexpression of permanently active AKTmyr inhibited TRAIL-mediated apoptosis via downregulation of TRAIL-R1 levels. Finally, AKT overactivation increased melanoma survival in cell culture and dramatically accelerated growth of melanoma transplant in vivo, highlighting a role of AKT suppression for effective anticancer treatment.
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Affiliation(s)
- Vladimir N Ivanov
- Center for Radiological Research, Columbia University College of Physicians and Surgeons, Columbia University, New York, NY 10032, USA.
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33
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Ivanov VN, Hei TK. Dual treatment with COX-2 inhibitor and sodium arsenite leads to induction of surface Fas Ligand expression and Fas-Ligand-mediated apoptosis in human melanoma cells. Exp Cell Res 2006; 312:1401-17. [PMID: 16487513 PMCID: PMC4376328 DOI: 10.1016/j.yexcr.2006.01.003] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2005] [Revised: 12/12/2005] [Accepted: 01/09/2006] [Indexed: 11/18/2022]
Abstract
Most human melanomas express Fas receptor on the cell surface, and treatment with exogenous Fas Ligand (FasL) efficiently induces apoptosis of these cells. In contrast, endogenous surface expression of FasL is suppressed in Fas-positive melanomas. We report here the use of a combination of sodium arsenite, an inhibitor of NF-kappaB activation, and NS398, a cyclooxygenase-2 (COX-2) inhibitor, for restoration of the surface FasL expression. We observed a large increase of Fas-mediated apoptosis in Fas-positive melanomas. This was due to induction of FasL surface expression and increased susceptibility to Fas death signaling after arsenite and NS398 treatment. Furthermore, silencing COX-2 expression by specific RNAi also effectively increased surface FasL expression following arsenite treatment. Upregulation of the surface FasL levels was based on an increase in the efficiency of translocation to the cell surface and stabilization of FasL protein on the cell surface, rather than on acceleration of the FasL gene transcription. Data obtained demonstrate that the combination of arsenite with inhibitors of COX-2 may affect the target cancer cells via induction of FasL-mediated death signaling.
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Affiliation(s)
- Vladimir N Ivanov
- Center for Radiological Research, Columbia University College of Physicians and Surgeons, New York, NY 10032, USA.
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34
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Yang H, Magilnick N, Ou X, Lu S. Tumour necrosis factor alpha induces co-ordinated activation of rat GSH synthetic enzymes via nuclear factor kappaB and activator protein-1. Biochem J 2006; 391:399-408. [PMID: 16011481 PMCID: PMC1276939 DOI: 10.1042/bj20050795] [Citation(s) in RCA: 60] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
GSH synthesis occurs via two enzymatic steps catalysed by GCL [glutamate-cysteine ligase, made up of GCLC (GCL catalytic subunit), and GCLM (GCL modifier subunit)] and GSS (GSH synthetase). Co-ordinated up-regulation of GCL and GSS further enhances GSH synthetic capacity. The present study examined whether TNFalpha (tumour necrosis factor alpha) influences the expression of rat GSH synthetic enzymes. To facilitate transcriptional studies of the rat GCLM, we cloned its 1.8 kb 5'-flanking region. TNFalpha induces the expression and recombinant promoter activities of GCLC, GCLM and GSS in H4IIE cells. TNFalpha induces NF-kappaB (nuclear factor kappaB) and AP-1 (activator protein 1) nuclear-binding activities. Blocking AP-1 with dominant negative c-Jun or NF-kappaB with IkappaBSR (IkappaB super-repressor, where IkappaB stands for inhibitory kappaB) lowered basal expression and inhibited the TNFalpha-mediated increase in mRNA levels of all three genes. While all three genes have multiple AP-1-binding sites, only GCLC has a NF-kappaB-binding site. Overexpression with p50 or p65 increased c-Jun mRNA levels, c-Jun-dependent promoter activity and the promoter activity of GCLM and GSS. Blocking NF-kappaB also lowered basal c-Jun expression and blunted the TNFalpha-mediated increase in c-Jun mRNA levels. TNFalpha treatment resulted in increased c-Jun and Nrf2 (nuclear factor erythroid 2-related factor 2) nuclear binding to the antioxidant response element of the rat GCLM and if this was prevented, TNFalpha no longer induced the GCLM promoter activity. In conclusion, both c-Jun and NF-kappaB are required for basal and TNFalpha-mediated induction of GSH synthetic enzymes in H4IIE cells. While NF-kappaB may exert a direct effect on the GCLC promoter, it induces the GCLM and GSS promoters indirectly via c-Jun.
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Affiliation(s)
- Heping Yang
- Division of Gastroenterology and Liver Diseases, University of Southern California (USC) Research Center for Liver Diseases, USC–University of California at Los Angeles Research Center for Alcoholic Liver and Pancreatic Diseases, Keck School of Medicine USC, Los Angeles, CA 90033, U.S.A
| | - Nathaniel Magilnick
- Division of Gastroenterology and Liver Diseases, University of Southern California (USC) Research Center for Liver Diseases, USC–University of California at Los Angeles Research Center for Alcoholic Liver and Pancreatic Diseases, Keck School of Medicine USC, Los Angeles, CA 90033, U.S.A
| | - Xiaopeng Ou
- Division of Gastroenterology and Liver Diseases, University of Southern California (USC) Research Center for Liver Diseases, USC–University of California at Los Angeles Research Center for Alcoholic Liver and Pancreatic Diseases, Keck School of Medicine USC, Los Angeles, CA 90033, U.S.A
| | - Shelly C. Lu
- Division of Gastroenterology and Liver Diseases, University of Southern California (USC) Research Center for Liver Diseases, USC–University of California at Los Angeles Research Center for Alcoholic Liver and Pancreatic Diseases, Keck School of Medicine USC, Los Angeles, CA 90033, U.S.A
- To whom correspondence should be addressed (email )
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Bhoumik A, Takahashi S, Breitweiser W, Shiloh Y, Jones N, Ronai Z. ATM-dependent phosphorylation of ATF2 is required for the DNA damage response. Mol Cell 2005; 18:577-87. [PMID: 15916964 PMCID: PMC2954254 DOI: 10.1016/j.molcel.2005.04.015] [Citation(s) in RCA: 130] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2004] [Revised: 03/13/2005] [Accepted: 04/26/2005] [Indexed: 01/21/2023]
Abstract
Activating transcription factor 2 (ATF2) is regulated by JNK/p38 in response to stress. Here, we demonstrate that the protein kinase ATM phosphorylates ATF2 on serines 490 and 498 following ionizing radiation (IR). Phosphoantibodies to ATF2(490/8) reveal dose- and time-dependent phosphorylation of ATF2 by ATM that results in its rapid colocalization with gamma-H2AX and MRN components into IR-induced foci (IRIF). Inhibition of ATF2 expression decreased recruitment of Mre11 to IRIF, abrogated S phase checkpoint, reduced activation of ATM, Chk1, and Chk2, and impaired radioresistance. ATF2 requires neither JNK/p38 nor its DNA binding domain for recruitment to IRIF and the S phase checkpoint. Our findings identify a role for ATF2 in the DNA damage response that is uncoupled from its transcriptional activity.
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Affiliation(s)
- Anindita Bhoumik
- Signal Transduction Program The Burnham Institute La Jolla, California 92037
| | - Shoichi Takahashi
- Signal Transduction Program The Burnham Institute La Jolla, California 92037
| | - Wolfgang Breitweiser
- Cell Regulation Laboratory Paterson Institute for Cancer Research Manchester, M204BX United Kingdom
| | - Yosef Shiloh
- Department of Human Genetics and Molecular Medicine Sackler School of Medicine Tel Aviv University Tel Aviv 69978 Israel
| | - Nic Jones
- Cell Regulation Laboratory Paterson Institute for Cancer Research Manchester, M204BX United Kingdom
| | - Ze'ev Ronai
- Signal Transduction Program The Burnham Institute La Jolla, California 92037
- Correspondence:
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Yang S, Yang Y, Raycraft J, Zhang H, Kanan S, Guo Y, Ronai Z, Hellstrom I, Hellstrom KE. Melanoma cells transfected to express CD83 induce antitumor immunity that can be increased by also engaging CD137. Proc Natl Acad Sci U S A 2004; 101:4990-5. [PMID: 15051893 PMCID: PMC387361 DOI: 10.1073/pnas.0400880101] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2003] [Indexed: 01/03/2023] Open
Abstract
Interactions between CD83 and its ligand(s) can up-regulate immune responses. M2-CD83 cells, derived by transfecting the M2 clone of mouse melanoma K1735 cells to express mouse CD83, were rejected by syngeneic mice, unless they were injected with a CD83Ig fusion protein. Rejection was mediated by CD4+ and CD8+ T cells plus natural killer cells, whereas rejection of M2-1D8 cells, which express anti-CD137 single-chain variable region fragments (scFv), occurs in the absence of CD8+ T cells. Furthermore, the tumor specificity of the immunity induced by the two cell lines differed. Immunization with live or mitomycin C-treated M2-CD83 cells prevented outgrowth of transplanted M2-WT cells and had therapeutic efficacy against established M2-WT tumors. A highly metastatic clone of K1735 cells, SW1-C, and its subline SW1-P2, which expresses an activating transcription factor 2-driven peptide, were then studied because they have particularly low immunogenicity. Neither SW1-C nor SW1-P2 cells became rejectable after expression of CD83 or anti-CD137 scFv. However, outgrowth of cells from either line was delayed in mice immunized against M2-CD83 or M2-1D8 cells, and immunization with a mixture of mitomycin C-treated cells from M2-CD83 plus M2-1D8 prevented tumor formation by SW1-P2 cells in five of five and by SW1-C cells in three of five mice. We conclude that M2 cells expressing CD83 can induce a tumor-destructive immune response also against SW1 cells and that this response can be made more effective by combining them with M2 cells expressing anti-CD137 scFv. A similar approach may be therapeutically beneficial against certain human cancers.
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Affiliation(s)
- Shilin Yang
- Pacific Northwest Research Institute, Seattle, WA 98122, USA
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Bhoumik A, Jones N, Ronai Z. Transcriptional switch by activating transcription factor 2-derived peptide sensitizes melanoma cells to apoptosis and inhibits their tumorigenicity. Proc Natl Acad Sci U S A 2004; 101:4222-7. [PMID: 15010535 PMCID: PMC384722 DOI: 10.1073/pnas.0400195101] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
The notorious resistance of melanoma cells to drug treatment can be overcome by expression of a 50-aa peptide derived from activating transcription factor 2 (ATF2(50-100)). Here we demonstrate that ATF2(50-100) induced apoptosis by sequestering ATF2 to the cytoplasm, thereby inhibiting its transcriptional activities. Furthermore, ATF2(50-100) binds to c-Jun N-terminal kinase (JNK) and increases its activity. Mutation within ATF2(50-100) that impairs association with JNK and the inhibition of JNK or c-Jun expression by RNA interference (RNAi) reduces the degree of ATF2(50-100)-induced apoptosis. In contrast, TAM67, a dominant negative of the Jun family of transcription factors, or JunD RNAi attenuates sensitization of melanoma cells expressing ATF2(50-100) to apoptosis after treatment with anisomycin, which is used as a model drug. Mutations within the JNK binding region of ATF2(50-100) or expression of TAM67 or JunD RNAi attenuates inhibition of melanoma's tumorigenicity by ATF2(50-100). We conclude that inhibition of ATF2 in concert with increased JNK/Jun and JunD activities is central for the sensitization of melanoma cells to apoptosis and inhibition of their tumorigenicity.
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Affiliation(s)
- Anindita Bhoumik
- Ruttenberg Cancer Center, Mount Sinai School of Medicine, New York, NY 10029, USA
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38
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Lieberman J, Song E, Lee SK, Shankar P. Interfering with disease: opportunities and roadblocks to harnessing RNA interference. Trends Mol Med 2003; 9:397-403. [PMID: 13129706 PMCID: PMC7128953 DOI: 10.1016/s1471-4914(03)00143-6] [Citation(s) in RCA: 71] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
RNA interference (RNAi) is an evolutionarily conserved mechanism for silencing gene expression by targeted degradation of mRNA. Short double-stranded RNAs, known as small interfering RNAs (siRNA), are incorporated into an RNA-induced silencing complex that directs degradation of RNA containing a homologous sequence. RNAi has been shown to work in mammalian cells, and can inhibit viral infection and control tumor cell growth in vitro. Recently, it has been shown that intravenous injection of siRNA or of plasmids expressing sequences processed to siRNA can protect mice from autoimmune and viral hepatitis. RNAi could provide an exciting new therapeutic modality for treating infection, cancer, neurodegenerative disease and other illnesses.
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Affiliation(s)
- Judy Lieberman
- Center for Blood Research and Department of Pediatrics, Harvard Medical School, Boston, MA 02115, USA.
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