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Abstract
In spite of the advances in antiretroviral therapy to treat HIV infection, the presence of a latent reservoir of HIV-infected cells represents the largest barrier towards finding a cure. Among the different strategies being pursued to eliminate or reduce this latent reservoir, the γc-cytokine IL-15 or its superagonist N-803 are currently under clinical investigation, either alone or with other interventions. They have been shown to reactivate latent HIV and enhance immune effector function, both of which are potentially required for effective reduction of latent reservoirs. In here, we present a comprehensive literature review of the different in vitro, ex vivo, and in vivo studies conducted to date that are aimed at targeting HIV reservoirs using IL-15 and N-803.
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Affiliation(s)
| | - Alberto Bosque
- Department of Microbiology, Immunology and Tropical Medicine, George Washington University, Washington, DC 20037, USA;
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2
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Kumar A, Schwab M, Laborit Labrada B, Silveira MAD, Goudreault M, Fournier É, Bellmann K, Beauchemin N, Gingras AC, Bilodeau S, Laplante M, Marette A. SHP-1 phosphatase acts as a coactivator of PCK1 transcription to control gluconeogenesis. J Biol Chem 2023; 299:105164. [PMID: 37595871 PMCID: PMC10504565 DOI: 10.1016/j.jbc.2023.105164] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2022] [Revised: 07/25/2023] [Accepted: 07/28/2023] [Indexed: 08/20/2023] Open
Abstract
We previously reported that the protein-tyrosine phosphatase SHP-1 (PTPN6) negatively regulates insulin signaling, but its impact on hepatic glucose metabolism and systemic glucose control remains poorly understood. Here, we use co-immunoprecipitation assays, chromatin immunoprecipitation sequencing, in silico methods, and gluconeogenesis assay, and found a new mechanism whereby SHP-1 acts as a coactivator for transcription of the phosphoenolpyruvate carboxykinase 1 (PCK1) gene to increase liver gluconeogenesis. SHP-1 is recruited to the regulatory regions of the PCK1 gene and interacts with RNA polymerase II. The recruitment of SHP-1 to chromatin is dependent on its association with the transcription factor signal transducer and activator of transcription 5 (STAT5). Loss of SHP-1 as well as STAT5 decrease RNA polymerase II recruitment to the PCK1 promoter and consequently PCK1 mRNA levels leading to blunted gluconeogenesis. This work highlights a novel nuclear role of SHP-1 as a key transcriptional regulator of hepatic gluconeogenesis adding a new mechanism to the repertoire of SHP-1 functions in metabolic control.
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Affiliation(s)
- Amit Kumar
- Faculté de Médecine, Centre de recherche de l'Institut universitaire de cardiologie et de pneumologie de Québec (CRIUCPQ), Université Laval, Québec, Quebec, Canada
| | - Michael Schwab
- Faculté de Médecine, Centre de recherche de l'Institut universitaire de cardiologie et de pneumologie de Québec (CRIUCPQ), Université Laval, Québec, Quebec, Canada
| | - Beisy Laborit Labrada
- Faculté de Médecine, Centre de recherche de l'Institut universitaire de cardiologie et de pneumologie de Québec (CRIUCPQ), Université Laval, Québec, Quebec, Canada
| | - Maruhen Amir Datsch Silveira
- Centre de Recherche du CHU de Québec - Université Laval, Axe Oncologie, Québec, Quebec, Canada; Centre de Recherche sur le Cancer de l'Université Laval, Québec, Quebec, Canada; Département de biologie moléculaire, biochimie médicale et pathologie, Faculté de Médecine, Université Laval, Québec, Quebec, Canada
| | - Marilyn Goudreault
- Institute for Research in Immunology and Cancer, Université de Montréal, Montréal, Quebec, Canada; Lunenfeld-Tanenbaum Research Institute, Mount Sinai Hospital, Sinai Health System, Toronto, Ontario, Canada
| | - Éric Fournier
- Centre de Recherche du CHU de Québec - Université Laval, Axe Oncologie, Québec, Quebec, Canada; Centre de Recherche sur le Cancer de l'Université Laval, Québec, Quebec, Canada; Département de biologie moléculaire, biochimie médicale et pathologie, Faculté de Médecine, Université Laval, Québec, Quebec, Canada; Centre de recherche en données massives de l'Université Laval, Québec, Quebec, Canada
| | - Kerstin Bellmann
- Faculté de Médecine, Centre de recherche de l'Institut universitaire de cardiologie et de pneumologie de Québec (CRIUCPQ), Université Laval, Québec, Quebec, Canada
| | - Nicole Beauchemin
- Department of Oncology, Medicine and Biochemistry, Rosalind and Morris Goodman Cancer Institute, McGill University, Montreal, Quebec, Canada
| | - Anne-Claude Gingras
- Lunenfeld-Tanenbaum Research Institute, Mount Sinai Hospital, Sinai Health System, Toronto, Ontario, Canada; Department of Molecular Genetics, University of Toronto, Toronto, Ontario, Canada
| | - Steve Bilodeau
- Centre de Recherche du CHU de Québec - Université Laval, Axe Oncologie, Québec, Quebec, Canada; Centre de Recherche sur le Cancer de l'Université Laval, Québec, Quebec, Canada; Département de biologie moléculaire, biochimie médicale et pathologie, Faculté de Médecine, Université Laval, Québec, Quebec, Canada; Centre de recherche en données massives de l'Université Laval, Québec, Quebec, Canada
| | - Mathieu Laplante
- Faculté de Médecine, Centre de recherche de l'Institut universitaire de cardiologie et de pneumologie de Québec (CRIUCPQ), Université Laval, Québec, Quebec, Canada; Centre de Recherche sur le Cancer de l'Université Laval, Québec, Quebec, Canada
| | - André Marette
- Faculté de Médecine, Centre de recherche de l'Institut universitaire de cardiologie et de pneumologie de Québec (CRIUCPQ), Université Laval, Québec, Quebec, Canada; Institute of Nutrition and Functional Foods, Laval University, Québec, Quebec, Canada.
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Vaparanta K, Jokilammi A, Paatero I, Merilahti JA, Heliste J, Hemanthakumar KA, Kivelä R, Alitalo K, Taimen P, Elenius K. STAT5b is a key effector of NRG-1/ERBB4-mediated myocardial growth. EMBO Rep 2023; 24:e56689. [PMID: 37009825 PMCID: PMC10157316 DOI: 10.15252/embr.202256689] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2022] [Revised: 03/07/2023] [Accepted: 03/10/2023] [Indexed: 04/04/2023] Open
Abstract
The growth factor Neuregulin-1 (NRG-1) regulates myocardial growth and is currently under clinical investigation as a treatment for heart failure. Here, we demonstrate in several in vitro and in vivo models that STAT5b mediates NRG-1/EBBB4-stimulated cardiomyocyte growth. Genetic and chemical disruption of the NRG-1/ERBB4 pathway reduces STAT5b activation and transcription of STAT5b target genes Igf1, Myc, and Cdkn1a in murine cardiomyocytes. Loss of Stat5b also ablates NRG-1-induced cardiomyocyte hypertrophy. Dynamin-2 is shown to control the cell surface localization of ERBB4 and chemical inhibition of Dynamin-2 downregulates STAT5b activation and cardiomyocyte hypertrophy. In zebrafish embryos, Stat5 is activated during NRG-1-induced hyperplastic myocardial growth, and chemical inhibition of the Nrg-1/Erbb4 pathway or Dynamin-2 leads to loss of myocardial growth and Stat5 activation. Moreover, CRISPR/Cas9-mediated knockdown of stat5b results in reduced myocardial growth and cardiac function. Finally, the NRG-1/ERBB4/STAT5b signaling pathway is differentially regulated at mRNA and protein levels in the myocardium of patients with pathological cardiac hypertrophy as compared to control human subjects, consistent with a role of the NRG-1/ERBB4/STAT5b pathway in myocardial growth.
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Affiliation(s)
- Katri Vaparanta
- Turku Bioscience CentreUniversity of Turku and Åbo Akademi UniversityTurkuFinland
- Medicity Research LaboratoriesUniversity of TurkuTurkuFinland
- Institute of BiomedicineUniversity of TurkuTurkuFinland
| | - Anne Jokilammi
- Turku Bioscience CentreUniversity of Turku and Åbo Akademi UniversityTurkuFinland
- Medicity Research LaboratoriesUniversity of TurkuTurkuFinland
- Institute of BiomedicineUniversity of TurkuTurkuFinland
| | - Ilkka Paatero
- Turku Bioscience CentreUniversity of Turku and Åbo Akademi UniversityTurkuFinland
| | - Johannes A Merilahti
- Turku Bioscience CentreUniversity of Turku and Åbo Akademi UniversityTurkuFinland
| | - Juho Heliste
- Turku Bioscience CentreUniversity of Turku and Åbo Akademi UniversityTurkuFinland
- Medicity Research LaboratoriesUniversity of TurkuTurkuFinland
- Institute of BiomedicineUniversity of TurkuTurkuFinland
| | - Karthik Amudhala Hemanthakumar
- Wihuri Research InstituteHelsinkiFinland
- Translational Cancer Biology Program, Research Programs Unit, Faculty of MedicineUniversity of HelsinkiHelsinkiFinland
| | - Riikka Kivelä
- Wihuri Research InstituteHelsinkiFinland
- Translational Cancer Biology Program, Research Programs Unit, Faculty of MedicineUniversity of HelsinkiHelsinkiFinland
- Faculty of Sport and Health SciencesUniversity of JyväskyläJyväskyläFinland
| | - Kari Alitalo
- Wihuri Research InstituteHelsinkiFinland
- Translational Cancer Biology Program, Research Programs Unit, Faculty of MedicineUniversity of HelsinkiHelsinkiFinland
| | - Pekka Taimen
- Institute of Biomedicine and FICAN West Cancer CentreUniversity of TurkuTurkuFinland
- Department of PathologyTurku University HospitalTurkuFinland
| | - Klaus Elenius
- Turku Bioscience CentreUniversity of Turku and Åbo Akademi UniversityTurkuFinland
- Medicity Research LaboratoriesUniversity of TurkuTurkuFinland
- Institute of BiomedicineUniversity of TurkuTurkuFinland
- Department of OncologyTurku University HospitalTurkuFinland
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4
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Welsh CL, Allen S, Madan LK. Setting sail: Maneuvering SHP2 activity and its effects in cancer. Adv Cancer Res 2023; 160:17-60. [PMID: 37704288 PMCID: PMC10500121 DOI: 10.1016/bs.acr.2023.03.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/15/2023]
Abstract
Since the discovery of tyrosine phosphorylation being a critical modulator of cancer signaling, proteins regulating phosphotyrosine levels in cells have fast become targets of therapeutic intervention. The nonreceptor protein tyrosine phosphatase (PTP) coded by the PTPN11 gene "SHP2" integrates phosphotyrosine signaling from growth factor receptors into the RAS/RAF/ERK pathway and is centrally positioned in processes regulating cell development and oncogenic transformation. Dysregulation of SHP2 expression or activity is linked to tumorigenesis and developmental defects. Even as a compelling anti-cancer target, SHP2 was considered "undruggable" for a long time owing to its conserved catalytic PTP domain that evaded drug development. Recently, SHP2 has risen from the "undruggable curse" with the discovery of small molecules that manipulate its intrinsic allostery for effective inhibition. SHP2's unique domain arrangement and conformation(s) allow for a truly novel paradigm of inhibitor development relying on skillful targeting of noncatalytic sites on proteins. In this review we summarize the biological functions, signaling properties, structural attributes, allostery and inhibitors of SHP2.
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Affiliation(s)
- Colin L Welsh
- Department of Cell and Molecular Pharmacology & Experimental Therapeutics, College of Medicine, Medical University of South Carolina, Charleston, SC, United States
| | - Sarah Allen
- Department of Pediatrics, Darby Children's Research Institute, Medical University of South Carolina, Charleston, SC, United States
| | - Lalima K Madan
- Department of Cell and Molecular Pharmacology & Experimental Therapeutics, College of Medicine, Medical University of South Carolina, Charleston, SC, United States; Hollings Cancer Center, Medical University of South Carolina, Charleston, SC, United States.
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Nguyen Huu T, Park J, Zhang Y, Duong Thanh H, Park I, Choi JM, Yoon HJ, Park SC, Woo HA, Lee SR. The Role of Oxidative Inactivation of Phosphatase PTEN and TCPTP in Fatty Liver Disease. Antioxidants (Basel) 2023; 12:antiox12010120. [PMID: 36670982 PMCID: PMC9854873 DOI: 10.3390/antiox12010120] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2022] [Revised: 12/29/2022] [Accepted: 12/30/2022] [Indexed: 01/05/2023] Open
Abstract
Alcoholic liver disease (ALD) and nonalcoholic fatty liver disease (NAFLD) are becoming increasingly prevalent worldwide. Despite the different etiologies, their spectra and histological feature are similar, from simple steatosis to more advanced stages such as steatohepatitis, fibrosis, cirrhosis, and hepatocellular carcinoma. Studies including peroxiredoxin knockout models revealed that oxidative stress is crucial in these diseases, which present as consequences of redox imbalance. Protein tyrosine phosphatases (PTPs) are a superfamily of enzymes that are major targets of reactive oxygen species (ROS) because of an oxidation-susceptible nucleophilic cysteine in their active site. Herein, we review the oxidative inactivation of two tumor suppressor PTPs, phosphatase and tensin homolog deleted on chromosome 10 (PTEN) and T-cell protein tyrosine phosphatase (TCPTP), and their contribution to the pathogenicity of ALD and NAFLD, respectively. This review might provide a better understanding of the pathogenic mechanisms of these diseases and help develop new therapeutic strategies to treat fatty liver disease.
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Affiliation(s)
- Thang Nguyen Huu
- Department of Biochemistry, Department of Biomedical Sciences, Research Center for Aging and Geriatrics, Research Institute of Medical Sciences, Chonnam National University Medical School, Gwangju 61469, Republic of Korea
- BioMedical Sciences Graduate Program (BMSGP), Chonnam National University Medical School, Hwasun 58 128, Republic of Korea
| | - Jiyoung Park
- College of Pharmacy, Graduate School of Pharmaceutical Sciences, Ewha Womans University, Seoul 120-750, Republic of Korea
| | - Ying Zhang
- Department of Cell Biology, School of Medicine, Jiangsu University, Zhenjiang 212013, China
| | - Hien Duong Thanh
- BioMedical Sciences Graduate Program (BMSGP), Chonnam National University Medical School, Hwasun 58 128, Republic of Korea
- Department of Anatomy, Chonnam National University Medical School, Gwangju 61469, Republic of Korea
| | - Iha Park
- Department of Biochemistry, Department of Biomedical Sciences, Research Center for Aging and Geriatrics, Research Institute of Medical Sciences, Chonnam National University Medical School, Gwangju 61469, Republic of Korea
| | - Jin Myung Choi
- Department of Biochemistry, Department of Biomedical Sciences, Research Center for Aging and Geriatrics, Research Institute of Medical Sciences, Chonnam National University Medical School, Gwangju 61469, Republic of Korea
| | - Hyun Joong Yoon
- Department of Biochemistry, Department of Biomedical Sciences, Research Center for Aging and Geriatrics, Research Institute of Medical Sciences, Chonnam National University Medical School, Gwangju 61469, Republic of Korea
| | - Sang Chul Park
- The Future Life and Society Research Center, Advanced Institute of Aging Science, Chonnam National University, Gwangju 61469, Republic of Korea
| | - Hyun Ae Woo
- College of Pharmacy, Graduate School of Pharmaceutical Sciences, Ewha Womans University, Seoul 120-750, Republic of Korea
| | - Seung-Rock Lee
- Department of Biochemistry, Department of Biomedical Sciences, Research Center for Aging and Geriatrics, Research Institute of Medical Sciences, Chonnam National University Medical School, Gwangju 61469, Republic of Korea
- Correspondence: ; Tel.: +82-61-379-2775; Fax: +82-61-379-2782
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Abstract
Src homology 2-containing protein tyrosine phosphatase 2 (SHP2) is a non-receptor protein tyrosine phosphatase ubiquitously expressed mainly in the cytoplasm of several tissues. SHP2 modulates diverse cell signaling events that control metabolism, cell growth, differentiation, cell migration, transcription and oncogenic transformation. It interacts with diverse molecules in the cell, and regulates key signaling events including RAS/ERK, PI3K/AKT, JAK/STAT and PD-1 pathways downstream of several receptor tyrosine kinases (RTKs) upon stimulation by growth factors and cytokines. SHP2 acts as both a phosphatase and a scaffold, and plays prominently oncogenic functions but can be tumor suppressor in a context-dependent manner. It typically acts as a positive regulator of RTKs signaling with some inhibitory functions reported as well. SHP2 expression and activity is regulated by such factors as allosteric autoinhibition, microRNAs, ubiquitination and SUMOylation. Dysregulation of SHP2 expression or activity causes many developmental diseases, and hematological and solid tumors. Moreover, upregulated SHP2 expression or activity also decreases sensitivity of cancer cells to anticancer drugs. SHP2 is now considered as a compelling anticancer drug target and several classes of SHP2 inhibitors with different mode of action are developed with some already in clinical trial phases. Moreover, novel SHP2 substrates and functions are rapidly growing both in cell and cancer. In view of this, we comprehensively and thoroughly reviewed literatures about SHP2 regulatory mechanisms, substrates and binding partners, biological functions, roles in human cancers, and different classes of small molecule inhibitors target this oncoprotein in cancer.
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Affiliation(s)
- Moges Dessale Asmamaw
- Department of Pharmacology, School of Basic Medical Sciences, State Key Laboratory for Esophageal Cancer Prevention and Treatment, Zhengzhou University, Zhengzhou, Henan Province, 450001, People's Republic of China
| | - Xiao-Jing Shi
- Academy of Medical Sciences, Zhengzhou University, Zhengzhou, Henan Province, 450052, People's Republic of China
| | - Li-Rong Zhang
- Department of Pharmacology, School of Basic Medical Sciences, State Key Laboratory for Esophageal Cancer Prevention and Treatment, Zhengzhou University, Zhengzhou, Henan Province, 450001, People's Republic of China.
| | - Hong-Min Liu
- School of Pharmaceutical Sciences, Zhengzhou University, Zhengzhou, 450001, Henan Province, China. .,Key Laboratory of Advanced Drug Preparation Technologies, Ministry of Education of China, Zhengzhou, Henan Province, 450001, People's Republic of China.
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Lu S, Peng X, Lin G, Xu K, Wang S, Qiu W, Du H, Chang K, Lv Y, Liu Y, Deng H, Hu C, Xu X. Grass carp (Ctenopharyngodon idellus) SHP2 suppresses IFN I expression via decreasing the phosphorylation of GSK3β in a non-contact manner. Fish Shellfish Immunol 2021; 116:150-160. [PMID: 34265416 DOI: 10.1016/j.fsi.2021.07.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/16/2020] [Revised: 07/05/2021] [Accepted: 07/11/2021] [Indexed: 02/07/2023]
Abstract
As a tyrosine phosphatase, Src homology 2-containing protein tyrosine phosphatase 2 (SHP2) serves as an inhibitor in PI3K-Akt pathway. In mammals, SHP2 can phosphorylate GSK3β at Y216 site to control the expression of IFN. So far, the multiple functions of SHP2 have been reported in mammals. However, little is known about fish SHP2. In this study, we cloned and identified a grass carp (Ctenopharyngodon idellus) SHP2 gene (CiSHP2, MT373151). SHP2 is conserved among different vertebrates by amino acid sequences alignment and the phylogenetic tree analysis. CiSHP2 shared the closest homology with Danio rerio SHP2. Simultaneously, SHP2 was also tested in grass carp tissues and CIK (C. idellus kidney) cells. We found that it responded to poly I:C stimulation. CiSHP2 was located in the cytoplasm just as the same as those of mammals. Interestingly, it inhibited the phosphorylation level of GSK3β in a non-contact manner. Meanwhile CiGSK3β interacted with and directly phosphorylated CiTBK1. In addition, we found that CiSHP2 also reduced the phosphorylation level of CiTBK1 by CiGSK3β, and then it depressed the expression of IFN I via GSK3β-TBK1 axis. These results suggested that CiSHP2 was involved in CiGSK3β and CiTBK1 activity but not regulated their transcriptional level. At the same time, we also found that CiSHP2 also influenced the activity of CiIRF3. Therefore, fish SHP2 inhibited IFN I expression through blocking GSK3β-TBK1 signal axis.
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Affiliation(s)
- Shina Lu
- School of Life Science, Nanchang University, Nanchang, 330031, Jiangxi, China
| | - Xiaojue Peng
- School of Life Science, Nanchang University, Nanchang, 330031, Jiangxi, China
| | - Gang Lin
- School of Life Science, Nanchang University, Nanchang, 330031, Jiangxi, China
| | - Kang Xu
- School of Life Science, Nanchang University, Nanchang, 330031, Jiangxi, China
| | - Shanghong Wang
- School of Life Science, Nanchang University, Nanchang, 330031, Jiangxi, China
| | - Weihua Qiu
- Teaching Material Research Office of Jiangxi Provincial Education Department, Nanchang, 330046, Jiangxi, China
| | - Hailing Du
- School of Life Science, Nanchang University, Nanchang, 330031, Jiangxi, China
| | - Kaile Chang
- School of Life Science, Nanchang University, Nanchang, 330031, Jiangxi, China
| | - Yangfeng Lv
- School of Life Science, Nanchang University, Nanchang, 330031, Jiangxi, China
| | - Yapeng Liu
- School of Life Science, Nanchang University, Nanchang, 330031, Jiangxi, China
| | - Hang Deng
- School of Life Science, Nanchang University, Nanchang, 330031, Jiangxi, China
| | - Chengyu Hu
- School of Life Science, Nanchang University, Nanchang, 330031, Jiangxi, China
| | - Xiaowen Xu
- School of Life Science, Nanchang University, Nanchang, 330031, Jiangxi, China.
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Wang YN, Liu S, Jia T, Feng Y, Xu X, Zhang D. T Cell Protein Tyrosine Phosphatase in Glucose Metabolism. Front Cell Dev Biol 2021; 9:682947. [PMID: 34268308 PMCID: PMC8276021 DOI: 10.3389/fcell.2021.682947] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2021] [Accepted: 06/09/2021] [Indexed: 11/17/2022] Open
Abstract
T cell protein tyrosine phosphatase (TCPTP), a vital regulator in glucose metabolism, inflammatory responses, and tumor processes, is increasingly considered a promising target for disease treatments and illness control. This review discusses the structure, substrates and main biological functions of TCPTP, as well as its regulatory effect in glucose metabolism, as an attempt to be referenced for formulating treatment strategies of metabolic disorders. Given the complicated regulation functions in different tissues and organs of TCPTP, the development of drugs inhibiting TCPTP with a higher specificity and a better biocompatibility is recognized as a promising therapeutic strategy for diabetes or obesity. Besides, treatments targeting TCPTP in a specific tissue or organ are suggested to be considerably promising.
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Affiliation(s)
- Ya-Nan Wang
- Department of Implantology, School and Hospital of Stomatology, Cheeloo College of Medicine, Shandong University, Jinan, China.,Shandong Key Laboratory of Oral Tissue Regeneration, Jinan, China.,Shandong Engineering Laboratory for Dental Materials and Oral Tissue Regeneration, Jinan, China
| | - Shiyue Liu
- Shandong Key Laboratory of Oral Tissue Regeneration, Jinan, China.,Shandong Engineering Laboratory for Dental Materials and Oral Tissue Regeneration, Jinan, China.,Department of Periodontology, School and Hospital of Stomatology, Cheeloo College of Medicine, Shandong University, Jinan, China
| | - Tingting Jia
- Department of Implantology, School and Hospital of Stomatology, Cheeloo College of Medicine, Shandong University, Jinan, China.,Shandong Key Laboratory of Oral Tissue Regeneration, Jinan, China.,Shandong Engineering Laboratory for Dental Materials and Oral Tissue Regeneration, Jinan, China
| | - Yao Feng
- Department of Implantology, School and Hospital of Stomatology, Cheeloo College of Medicine, Shandong University, Jinan, China.,Shandong Key Laboratory of Oral Tissue Regeneration, Jinan, China.,Shandong Engineering Laboratory for Dental Materials and Oral Tissue Regeneration, Jinan, China
| | - Xin Xu
- Department of Implantology, School and Hospital of Stomatology, Cheeloo College of Medicine, Shandong University, Jinan, China.,Shandong Key Laboratory of Oral Tissue Regeneration, Jinan, China.,Shandong Engineering Laboratory for Dental Materials and Oral Tissue Regeneration, Jinan, China
| | - Dongjiao Zhang
- Department of Implantology, School and Hospital of Stomatology, Cheeloo College of Medicine, Shandong University, Jinan, China.,Shandong Key Laboratory of Oral Tissue Regeneration, Jinan, China.,Shandong Engineering Laboratory for Dental Materials and Oral Tissue Regeneration, Jinan, China
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9
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Zhang L, Zhang J, Liu Y, Zhang P, Nie J, Zhao R, Shi Q, Sun H, Jiao D, Chen Y, Zhao X, Huang Y, Li Y, Zhao JY, Xu W, Zhao SM, Wang C. Mitochondrial STAT5A promotes metabolic remodeling and the Warburg effect by inactivating the pyruvate dehydrogenase complex. Cell Death Dis 2021; 12:634. [PMID: 34148062 PMCID: PMC8214628 DOI: 10.1038/s41419-021-03908-0] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2020] [Revised: 05/31/2021] [Accepted: 06/07/2021] [Indexed: 12/12/2022]
Abstract
Signal transducer and activator 5a (STAT5A) is a classical transcription factor that plays pivotal roles in various biological processes, including tumor initiation and progression. A fraction of STAT5A is localized in the mitochondria, but the biological functions of mitochondrial STAT5A remain obscure. Here, we show that STAT5A interacts with pyruvate dehydrogenase complex (PDC), a mitochondrial gatekeeper enzyme connecting two key metabolic pathways, glycolysis and the tricarboxylic acid cycle. Mitochondrial STAT5A disrupts PDC integrity, thereby inhibiting PDC activity and remodeling cellular glycolysis and oxidative phosphorylation. Mitochondrial translocation of STAT5A is increased under hypoxic conditions. This strengthens the Warburg effect in cancer cells and promotes in vitro cell growth under hypoxia and in vivo tumor growth. Our findings indicate distinct pro-oncogenic roles of STAT5A in energy metabolism, which is different from its classical function as a transcription factor.
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Affiliation(s)
- Liang Zhang
- Obstetrics & Gynecology Hospital of Fudan University, State Key Laboratory of Genetic Engineering, MOE Engineering Research Center of Gene Technology, Key Laboratory of Reproduction Regulation of NPFPC (SIPPR, IRD), School of Life Sciences, Fudan University, 200438, Shanghai, China
| | - Jianong Zhang
- Obstetrics & Gynecology Hospital of Fudan University, State Key Laboratory of Genetic Engineering, MOE Engineering Research Center of Gene Technology, Key Laboratory of Reproduction Regulation of NPFPC (SIPPR, IRD), School of Life Sciences, Fudan University, 200438, Shanghai, China
| | - Yan Liu
- Institute of metabolism and integrative biology (IMIB), School of Life Sciences, Fudan University, 200438, Shanghai, China
| | - Pingzhao Zhang
- Fudan University Shanghai Cancer Center and Department of Pathology, School of Basic Medical Sciences, Shanghai Medical College, Fudan University, 200032, Shanghai, China
| | - Ji Nie
- Obstetrics & Gynecology Hospital of Fudan University, State Key Laboratory of Genetic Engineering, MOE Engineering Research Center of Gene Technology, Key Laboratory of Reproduction Regulation of NPFPC (SIPPR, IRD), School of Life Sciences, Fudan University, 200438, Shanghai, China
| | - Rui Zhao
- Obstetrics & Gynecology Hospital of Fudan University, State Key Laboratory of Genetic Engineering, MOE Engineering Research Center of Gene Technology, Key Laboratory of Reproduction Regulation of NPFPC (SIPPR, IRD), School of Life Sciences, Fudan University, 200438, Shanghai, China
| | - Qin Shi
- Obstetrics & Gynecology Hospital of Fudan University, State Key Laboratory of Genetic Engineering, MOE Engineering Research Center of Gene Technology, Key Laboratory of Reproduction Regulation of NPFPC (SIPPR, IRD), School of Life Sciences, Fudan University, 200438, Shanghai, China
| | - Huiru Sun
- Obstetrics & Gynecology Hospital of Fudan University, State Key Laboratory of Genetic Engineering, MOE Engineering Research Center of Gene Technology, Key Laboratory of Reproduction Regulation of NPFPC (SIPPR, IRD), School of Life Sciences, Fudan University, 200438, Shanghai, China
| | - Dongyue Jiao
- Obstetrics & Gynecology Hospital of Fudan University, State Key Laboratory of Genetic Engineering, MOE Engineering Research Center of Gene Technology, Key Laboratory of Reproduction Regulation of NPFPC (SIPPR, IRD), School of Life Sciences, Fudan University, 200438, Shanghai, China
| | - Yingji Chen
- Obstetrics & Gynecology Hospital of Fudan University, State Key Laboratory of Genetic Engineering, MOE Engineering Research Center of Gene Technology, Key Laboratory of Reproduction Regulation of NPFPC (SIPPR, IRD), School of Life Sciences, Fudan University, 200438, Shanghai, China
| | - Xiaying Zhao
- Obstetrics & Gynecology Hospital of Fudan University, State Key Laboratory of Genetic Engineering, MOE Engineering Research Center of Gene Technology, Key Laboratory of Reproduction Regulation of NPFPC (SIPPR, IRD), School of Life Sciences, Fudan University, 200438, Shanghai, China
| | - Yan Huang
- Obstetrics & Gynecology Hospital of Fudan University, State Key Laboratory of Genetic Engineering, MOE Engineering Research Center of Gene Technology, Key Laboratory of Reproduction Regulation of NPFPC (SIPPR, IRD), School of Life Sciences, Fudan University, 200438, Shanghai, China
| | - Yao Li
- Obstetrics & Gynecology Hospital of Fudan University, State Key Laboratory of Genetic Engineering, MOE Engineering Research Center of Gene Technology, Key Laboratory of Reproduction Regulation of NPFPC (SIPPR, IRD), School of Life Sciences, Fudan University, 200438, Shanghai, China
| | - Jian-Yuan Zhao
- State Key Laboratory of Genetic Engineering, School of Life Sciences, Fudan University, 200438, Shanghai, China
| | - Wei Xu
- Shanghai Fifth People's Hospital and Institutes of Biomedical Sciences, Fudan University, 20032, Shanghai, China
| | - Shi-Min Zhao
- Obstetrics & Gynecology Hospital of Fudan University, State Key Laboratory of Genetic Engineering, MOE Engineering Research Center of Gene Technology, Key Laboratory of Reproduction Regulation of NPFPC (SIPPR, IRD), School of Life Sciences, Fudan University, 200438, Shanghai, China.
| | - Chenji Wang
- Obstetrics & Gynecology Hospital of Fudan University, State Key Laboratory of Genetic Engineering, MOE Engineering Research Center of Gene Technology, Key Laboratory of Reproduction Regulation of NPFPC (SIPPR, IRD), School of Life Sciences, Fudan University, 200438, Shanghai, China.
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10
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Jones DM, Read KA, Oestreich KJ. Dynamic Roles for IL-2-STAT5 Signaling in Effector and Regulatory CD4 + T Cell Populations. J Immunol 2021; 205:1721-1730. [PMID: 32958706 DOI: 10.4049/jimmunol.2000612] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/26/2020] [Accepted: 06/22/2020] [Indexed: 12/22/2022]
Abstract
CD4+ Th cells are responsible for orchestrating diverse, pathogen-specific immune responses through their differentiation into a number of subsets, including TH1, TH2, TH9, T follicular helper, T follicular regulatory, and regulatory T cells. The differentiation of each subset is guided by distinct regulatory requirements, including those derived from extracellular cytokine signals. IL-2 has emerged as a critical immunomodulatory cytokine that both positively and negatively affects the differentiation of individual Th cell subsets. IL-2 signals are propagated, in part, via activation of STAT5, which functions as a key regulator of CD4+ T cell gene programs. In this review, we discuss current understanding of the mechanisms that allow IL-2-STAT5 signaling to exert divergent effects across CD4+ T cell subsets and highlight specific roles for this pathway in the regulation of individual Th cell differentiation programs.
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Affiliation(s)
- Devin M Jones
- Department of Microbial Infection and Immunity, The Ohio State University College of Medicine and Wexner Medical Center, Columbus, OH 43210; and.,Biomedical Sciences Graduate Program, The Ohio State University College of Medicine and Wexner Medical Center, Columbus, OH 43210
| | - Kaitlin A Read
- Department of Microbial Infection and Immunity, The Ohio State University College of Medicine and Wexner Medical Center, Columbus, OH 43210; and.,Biomedical Sciences Graduate Program, The Ohio State University College of Medicine and Wexner Medical Center, Columbus, OH 43210
| | - Kenneth J Oestreich
- Department of Microbial Infection and Immunity, The Ohio State University College of Medicine and Wexner Medical Center, Columbus, OH 43210; and
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11
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Cai YQ, Lv Y, Mo ZC, Lei J, Zhu JL, Zhong QQ. Multiple pathophysiological roles of midkine in human disease. Cytokine 2020; 135:155242. [PMID: 32799009 DOI: 10.1016/j.cyto.2020.155242] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2020] [Revised: 08/07/2020] [Accepted: 08/07/2020] [Indexed: 12/27/2022]
Abstract
Midkine (MK) is a low molecular-weight protein that was first identified as the product of a retinoic acid-responsive gene involved in embryonic development. Recent studies have indicated that MK levels are related to various diseases, including cardiovascular disease (CVD), renal disease and autoimmune disease. MK is a growth factor involved in multiple pathophysiological processes, such as inflammation, the repair of damaged tissues and cancer. The pathophysiological roles of MK are diverse. MK enhances the recruitment and migration of inflammatory cells upon inflammation directly and also through induction of chemokines, and contributes to tissue damage. In lung endothelial cells, oxidative stress increased the expression of MK, which induced angiotensin-converting enzyme (ACE) expression and the consequent conversion from Ang I to Ang II, leading to further oxidative stress. MK inhibited cholesterol efflux from macrophages by reducing ATP-binding cassette transporter A1 (ABCA1) expression, which is involved in lipid metabolism, suggesting that MK is an important positive factor involved in inflammation, oxidative stress and lipid metabolism. Furthermore, MK can regulate the expansion, differentiation and activation of T cells as well as B-cell survival; mediate angiogenic and antibacterial activity; and possess anti-apoptotic activity. In this paper, we summarize the pathophysiological roles of MK in human disease.
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Affiliation(s)
- Ya-Qin Cai
- Hunan Province Innovative Training Base for Medical Postgraduates, Clinical Anatomy & Reproductive Medicine Application Institute, University of South China, Hengyang 421001, China; Institute of Basic Medical Sciences, Guilin Medical University, Guilin 541199, Guangxi, China
| | - Yuncheng Lv
- Hunan Province Innovative Training Base for Medical Postgraduates, Clinical Anatomy & Reproductive Medicine Application Institute, University of South China, Hengyang 421001, China; Institute of Basic Medical Sciences, Guilin Medical University, Guilin 541199, Guangxi, China
| | - Zhong-Cheng Mo
- Hunan Province Innovative Training Base for Medical Postgraduates, Clinical Anatomy & Reproductive Medicine Application Institute, University of South China, Hengyang 421001, China; Institute of Basic Medical Sciences, Guilin Medical University, Guilin 541199, Guangxi, China
| | - Jiashun Lei
- Hunan Province Innovative Training Base for Medical Postgraduates, Clinical Anatomy & Reproductive Medicine Application Institute, University of South China, Hengyang 421001, China
| | - Jing-Ling Zhu
- Hunan Province Innovative Training Base for Medical Postgraduates, Clinical Anatomy & Reproductive Medicine Application Institute, University of South China, Hengyang 421001, China
| | - Qiao-Qing Zhong
- Department of Cardiovascular Medicine, Xiangya Hospital, Central South University, Changsha 410008, China.
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12
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Zimmerman MG, Bowen JR, McDonald CE, Young E, Baric RS, Pulendran B, Suthar MS. STAT5: a Target of Antagonism by Neurotropic Flaviviruses. J Virol 2019; 93:e00665-19. [PMID: 31534033 PMCID: PMC6854481 DOI: 10.1128/jvi.00665-19] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2019] [Accepted: 08/30/2019] [Indexed: 01/08/2023] Open
Abstract
Flaviviruses are a diverse group of arthropod-borne viruses responsible for numerous significant public health threats; therefore, understanding the interactions between these viruses and the human immune response remains vital. West Nile virus (WNV) and Zika virus (ZIKV) infect human dendritic cells (DCs) and can block antiviral immune responses in DCs. Previously, we used mRNA sequencing and weighted gene coexpression network analysis (WGCNA) to define molecular signatures of antiviral DC responses following activation of innate immune signaling (RIG-I, MDA5, or type I interferon [IFN] signaling) or infection with WNV. Using this approach, we found that several genes involved in T cell cosignaling and antigen processing were not enriched in DCs during WNV infection. Using cis-regulatory sequence analysis, STAT5 was identified as a regulator of DC activation and immune responses downstream of innate immune signaling that was not activated during either WNV or ZIKV infection. Mechanistically, WNV and ZIKV actively blocked STAT5 phosphorylation downstream of RIG-I, IFN-β, and interleukin-4 (IL-4), but not granulocyte-macrophage colony-stimulating factor (GM-CSF), signaling. Unexpectedly, dengue virus serotypes 1 to 4 (DENV1 to DENV4) and the yellow fever 17D vaccine strain (YFV-17D) did not antagonize STAT5 phosphorylation. In contrast to WNV, ZIKV inhibited JAK1 and TYK2 phosphorylation following type I IFN treatment, suggesting divergent mechanisms used by these viruses to inhibit STAT5 activation. Combined, these findings identify STAT5 as a target of antagonism by specific pathogenic flaviviruses to subvert the immune response in infected DCs.IMPORTANCE Flaviviruses are a diverse group of insect-borne viruses responsible for numerous significant public health threats. Previously, we used a computational biology approach to define molecular signatures of antiviral DC responses following activation of innate immune signaling or infection with West Nile virus (WNV). In this work, we identify STAT5 as a regulator of DC activation and antiviral immune responses downstream of innate immune signaling that was not activated during either WNV or Zika virus (ZIKV) infection. WNV and ZIKV actively blocked STAT5 phosphorylation downstream of RIG-I, IFN-β, and IL-4, but not GM-CSF, signaling. However, other related flaviviruses, dengue virus serotypes 1 to 4 and the yellow fever 17D vaccine strain, did not antagonize STAT5 phosphorylation. Mechanistically, WNV and ZIKV showed differential inhibition of Jak kinases upstream of STAT5, suggesting divergent countermeasures to inhibit STAT5 activation. Combined, these findings identify STAT5 as a target of antagonism by specific pathogenic flaviviruses to subvert antiviral immune responses in human DCs.
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Affiliation(s)
- Matthew G Zimmerman
- Department of Pediatrics, Division of Infectious Diseases, Emory University School of Medicine, Atlanta, Georgia, USA
- Emory Vaccine Center, Yerkes National Primate Research Center, Atlanta, Georgia, USA
| | - James R Bowen
- Department of Pediatrics, Division of Infectious Diseases, Emory University School of Medicine, Atlanta, Georgia, USA
- Emory Vaccine Center, Yerkes National Primate Research Center, Atlanta, Georgia, USA
| | - Circe E McDonald
- Department of Pediatrics, Division of Infectious Diseases, Emory University School of Medicine, Atlanta, Georgia, USA
- Emory Vaccine Center, Yerkes National Primate Research Center, Atlanta, Georgia, USA
| | - Ellen Young
- Department of Epidemiology, Gillings School of Global Public Health, University of North Carolina, Chapel Hill, North Carolina, USA
| | - Ralph S Baric
- Department of Epidemiology, Gillings School of Global Public Health, University of North Carolina, Chapel Hill, North Carolina, USA
- Department of Microbiology and Immunology, School of Medicine, University of North Carolina, Chapel Hill, North Carolina, USA
| | - Bali Pulendran
- Emory Vaccine Center, Yerkes National Primate Research Center, Atlanta, Georgia, USA
- Department of Pathology and Laboratory Medicine, Emory University School of Medicine, Atlanta, Georgia, USA
| | - Mehul S Suthar
- Department of Pediatrics, Division of Infectious Diseases, Emory University School of Medicine, Atlanta, Georgia, USA
- Emory Vaccine Center, Yerkes National Primate Research Center, Atlanta, Georgia, USA
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Wójcik M, Krawczyńska A, Antushevich H, Herman AP. Post-Receptor Inhibitors of the GHR-JAK2-STAT Pathway in the Growth Hormone Signal Transduction. Int J Mol Sci 2018; 19:E1843. [PMID: 29932147 PMCID: PMC6073700 DOI: 10.3390/ijms19071843] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2018] [Revised: 06/15/2018] [Accepted: 06/19/2018] [Indexed: 02/06/2023] Open
Abstract
The growth hormone (GH) plays a key role in the regulation of metabolic processes in an organism. Determination of the correct structure and functioning of the growth hormone receptor (GHR) allowed for a more detailed research of its post-receptor regulators, which substantially influences its signal transduction. This review is focused on the description of the post-receptor inhibitors of the GHR-JAK2-STAT pathway, which is one of the most important pathways in the transduction of the somatotropic axis signal. The aim of this review is the short characterization of the main post-receptor inhibitors, such as: cytokine-inducible SH2-containing protein (CIS), Suppressors of Cytokine Signaling (SOCS) 1, 2 and 3, sirtuin 1 (SIRT1), protein inhibitors of activated STAT (PIAS) 1, 3 and PIAS4, protein tyrosine phosphatases (PTP) 1B and H1, Src homology 2 (SH2) domain containing protein tyrosine phosphatase (SHP) 1, 2 and signal regulatory protein (SIRP) α1. The equilibrium between these regulators activity and inhibition is of special concern because, as many studies showed, even slight imbalance may disrupt the GH activity causing serious diseases. The regulation of the described inhibitors expression and activity may be a point of interest for pharmaceutical industry.
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Affiliation(s)
- Maciej Wójcik
- The Kielanowski Institute of Animal Physiology and Nutrition, Polish Academy of Sciences, ul. Instytucka 3, 05-110 Jabłonna, Poland.
| | - Agata Krawczyńska
- The Kielanowski Institute of Animal Physiology and Nutrition, Polish Academy of Sciences, ul. Instytucka 3, 05-110 Jabłonna, Poland.
| | - Hanna Antushevich
- The Kielanowski Institute of Animal Physiology and Nutrition, Polish Academy of Sciences, ul. Instytucka 3, 05-110 Jabłonna, Poland.
| | - Andrzej Przemysław Herman
- The Kielanowski Institute of Animal Physiology and Nutrition, Polish Academy of Sciences, ul. Instytucka 3, 05-110 Jabłonna, Poland.
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Kim AR, Ulirsch JC, Wilmes S, Unal E, Moraga I, Karakukcu M, Yuan D, Kazerounian S, Abdulhay NJ, King DS, Gupta N, Gabriel SB, Lander ES, Patiroglu T, Ozcan A, Ozdemir MA, Garcia KC, Piehler J, Gazda HT, Klein DE, Sankaran VG. Functional Selectivity in Cytokine Signaling Revealed Through a Pathogenic EPO Mutation. Cell 2017; 168:1053-1064.e15. [PMID: 28283061 DOI: 10.1016/j.cell.2017.02.026] [Citation(s) in RCA: 79] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2016] [Revised: 11/30/2016] [Accepted: 02/15/2017] [Indexed: 12/16/2022]
Abstract
Cytokines are classically thought to stimulate downstream signaling pathways through monotonic activation of receptors. We describe a severe anemia resulting from a homozygous mutation (R150Q) in the cytokine erythropoietin (EPO). Surprisingly, the EPO R150Q mutant shows only a mild reduction in affinity for its receptor but has altered binding kinetics. The EPO mutant is less effective at stimulating erythroid cell proliferation and differentiation, even at maximally potent concentrations. While the EPO mutant can stimulate effectors such as STAT5 to a similar extent as the wild-type ligand, there is reduced JAK2-mediated phosphorylation of select downstream targets. This impairment in downstream signaling mechanistically arises from altered receptor dimerization dynamics due to extracellular binding changes. These results demonstrate how variation in a single cytokine can lead to biased downstream signaling and can thereby cause human disease. Moreover, we have defined a distinct treatable form of anemia through mutation identification and functional studies.
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15
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Able AA, Burrell JA, Stephens JM. STAT5-Interacting Proteins: A Synopsis of Proteins that Regulate STAT5 Activity. Biology (Basel) 2017; 6:biology6010020. [PMID: 28287479 PMCID: PMC5372013 DOI: 10.3390/biology6010020] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/20/2017] [Revised: 02/27/2017] [Accepted: 03/06/2017] [Indexed: 01/17/2023]
Abstract
Signal Transducers and Activators of Transcription (STATs) are key components of the JAK/STAT pathway. Of the seven STATs, STAT5A and STAT5B are of particular interest for their critical roles in cellular differentiation, adipogenesis, oncogenesis, and immune function. The interactions of STAT5A and STAT5B with cytokine/hormone receptors, nuclear receptors, transcriptional regulators, proto-oncogenes, kinases, and phosphatases all contribute to modulating STAT5 activity. Among these STAT5 interacting proteins, some serve as coactivators or corepressors to regulate STAT5 transcriptional activity and some proteins can interact with STAT5 to enhance or repress STAT5 signaling. In addition, a few STAT5 interacting proteins have been identified as positive regulators of STAT5 that alter serine and tyrosine phosphorylation of STAT5 while other proteins have been identified as negative regulators of STAT5 via dephosphorylation. This review article will discuss how STAT5 activity is modulated by proteins that physically interact with STAT5.
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Affiliation(s)
- Ashley A Able
- Adipocyte Biology Laboratory, Pennington Biomedical Research Center, Baton Rouge, LA 70808, USA.
- Department of Biological Sciences, Louisiana State University, Baton Rouge, LA 70803, USA.
| | - Jasmine A Burrell
- Adipocyte Biology Laboratory, Pennington Biomedical Research Center, Baton Rouge, LA 70808, USA.
- Department of Biological Sciences, Louisiana State University, Baton Rouge, LA 70803, USA.
| | - Jacqueline M Stephens
- Adipocyte Biology Laboratory, Pennington Biomedical Research Center, Baton Rouge, LA 70808, USA.
- Department of Biological Sciences, Louisiana State University, Baton Rouge, LA 70803, USA.
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16
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Zea AH, Stewart T, Ascani J, Tate DJ, Finkel-Jimenez B, Wilk A, Reiss K, Smoyer WE, Aviles DH. Activation of the IL-2 Receptor in Podocytes: A Potential Mechanism for Podocyte Injury in Idiopathic Nephrotic Syndrome? PLoS One 2016; 11:e0157907. [PMID: 27389192 PMCID: PMC4936730 DOI: 10.1371/journal.pone.0157907] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2015] [Accepted: 06/07/2016] [Indexed: 12/16/2022] Open
Abstract
The renal podocyte plays an important role in maintaining the structural integrity of the glomerular basement membrane. We have previously reported that patients with idiopathic nephrotic syndrome (INS) have increased IL-2 production. We hypothesized that podocytes express an IL-2 receptor (IL-2R) and signaling through this receptor can result in podocyte injury. To confirm the presence of the IL-2R, we tested a conditionally immortalized murine podocyte cell line by flow cytometry, qPCR, and Western blot. To test for the presence of the IL-2R in vivo, immunohistochemical staining was performed on human renal biopsies in children with FSGS and control. Podocytes were stimulated with IL-2 in vitro, to study signaling events via the JAK/STAT pathway. The results showed that stimulation with IL-2 resulted in increased mRNA and protein expression of STAT 5a, phosphorylated STAT 5, JAK 3, and phosphorylated JAK 3. We then investigated for signs of cellular injury and the data showed that pro-apoptotic markers Bax and cFLIP were significantly increased following IL-2 exposure, whereas LC3 II was decreased. Furthermore, mitochondrial depolarization and apoptosis were both significantly increased following activation of the IL-2R. We used a paracellular permeability assay to monitor the structural integrity of a podocyte monolayer following IL-2 exposure. The results showed that podocytes exposed to IL-2 have increased albumin leakage across the monolayer. We conclude that murine podocytes express the IL-2R, and that activation through the IL-2R results in podocyte injury.
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Affiliation(s)
- Arnold H. Zea
- Department of Microbiology, Immunology, and Parasitology, Louisiana State University Health Sciences Center, New Orleans, Louisiana, United States of America
| | - Tyrus Stewart
- Department of Pediatric Nephrology, Louisiana State University Health Sciences Center, New Orleans, Louisiana, United States of America
| | - Jeannine Ascani
- Department of Research Ochsner Biobank, Ochsner Health System, New Orleans, Louisiana, United States of America
| | - David J. Tate
- Eurofins Central Analytical Laboratories, New Orleans, Louisiana, United States of America
| | - Beatriz Finkel-Jimenez
- Department of Medical Microbiology and Immunology, American University of the Caribbean School of Medicine, Coral Gables, Florida, United States of America
| | - Anna Wilk
- Department of Genetics, Louisiana State University Health Sciences Center, New Orleans, Louisiana, United States of America
| | - Krzysztof Reiss
- Department of Genetics, Louisiana State University Health Sciences Center, New Orleans, Louisiana, United States of America
| | - William E. Smoyer
- Department of Nephrology, Nationwide Children’s Hospital, Columbus, Ohio, United States of America
| | - Diego H. Aviles
- Department of Pediatric Nephrology, Louisiana State University Health Sciences Center, New Orleans, Louisiana, United States of America
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Hsiao WY, Lin YC, Liao FH, Chan YC, Huang CY. Dual-Specificity Phosphatase 4 Regulates STAT5 Protein Stability and Helper T Cell Polarization. PLoS One 2015; 10:e0145880. [PMID: 26710253 DOI: 10.1371/journal.pone.0145880] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2015] [Accepted: 12/09/2015] [Indexed: 11/23/2022] Open
Abstract
Immune responses are critically regulated by the functions of CD4 helper T cells. Based on their secreted cytokines, helper T cells are further categorized into different subsets like Treg or Th17 cells, which suppress or promote inflammatory responses, respectively. Signals from IL-2 activate the transcription factor STAT5 to promote Treg but suppress Th17 cell differentiation. Our previous results found that the deficiency of a dual-specificity phosphatase, DUSP4, induced STAT5 hyper-activation, enhanced IL-2 signaling, and increased T cell proliferation. In this report, we examined the effects of DUSP4 deficiency on helper T cell differentiation and STAT5 regulation. Our in vivo data showed that DUSP4 mice were more resistant to the induction of autoimmune encephalitis, while in vitro differentiations revealed enhanced iTreg and reduced Th17 polarization in DUSP4-deficient T cells. To study the cause of this altered helper T cell polarization, we performed luciferase reporter assays and confirmed that, as predicted by our previous report, DUSP4 over-expression suppressed the transcription factor activity of STAT5. Surprisingly, we also found that DUSP4-deficient T but not B cells exhibited elevated STAT5 protein levels, and over-expressed DUSP4 destabilized STAT5 in vitro; moreover, this destabilization required the phosphatase activity of DUSP4, and was insensitive to MG132 treatment. Finally, domain-mapping results showed that both the substrate-interacting and the phosphatase domains of DUSP4 were required for its optimal interaction with STAT5, while the coiled-coil domain of STAT5 appeared to hinder this interaction. Our data thus provide the first genetic evidence that DUSP4 is important for helper T cell development. In addition, they also help uncover the novel, DUSP4-mediated regulation of STAT5 protein stability.
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18
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Coulombe G, Rivard N. New and Unexpected Biological Functions for the Src-Homology 2 Domain-Containing Phosphatase SHP-2 in the Gastrointestinal Tract. Cell Mol Gastroenterol Hepatol 2015; 2:11-21. [PMID: 28174704 PMCID: PMC4980741 DOI: 10.1016/j.jcmgh.2015.11.001] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/28/2015] [Accepted: 11/10/2015] [Indexed: 12/13/2022]
Abstract
SHP-2 is a tyrosine phosphatase expressed in most embryonic and adult tissues. SHP-2 regulates many cellular functions including growth, differentiation, migration, and survival. Genetic and biochemical evidence show that SHP-2 is required for rat sarcoma viral oncogene/extracellular signal-regulated kinases mitogen-activated protein kinase pathway activation by most tyrosine kinase receptors, as well as by G-protein-coupled and cytokine receptors. In addition, SHP-2 can regulate the Janus kinase/signal transducers and activators of transcription, nuclear factor-κB, phosphatidyl-inositol 3-kinase/Akt, RhoA, Hippo, and Wnt/β-catenin signaling pathways. Emerging evidence has shown that SHP-2 dysfunction represents a key factor in the pathogenesis of gastrointestinal diseases, in particular in chronic inflammation and cancer. Variations within the gene locus encoding SHP-2 have been associated with increased susceptibility to develop ulcerative colitis and gastric atrophy. Furthermore, mice with conditional deletion of SHP-2 in intestinal epithelial cells rapidly develop severe colitis. Similarly, hepatocyte-specific deletion of SHP-2 induces hepatic inflammation, resulting in regenerative hyperplasia and development of tumors in aged mice. However, the SHP-2 gene initially was suggested to be a proto-oncogene because activating mutations of this gene were found in pediatric leukemias and certain forms of liver and colon cancers. Moreover, SHP-2 expression is up-regulated in gastric and hepatocellular cancers. Notably, SHP-2 functions downstream of cytotoxin-associated antigen A (CagA), the major virulence factor of Helicobacter pylori, and is associated with increased risks of gastric cancer. Further compounding this complexity, most recent findings suggest that SHP-2 also coordinates carbohydrate, lipid, and bile acid synthesis in the liver and pancreas. This review aims to summarize current knowledge and recent data regarding the biological functions of SHP-2 in the gastrointestinal tract.
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Key Words
- CagA, cytotoxin-associated gene A
- ERK, extracellular signal-regulated kinases
- FGF, fibroblast growth factor
- GI, gastrointestinal
- HCC, hepatocellular carcinoma
- IBD, inflammatory bowel disease
- IEC, intestinal epithelial cell
- JMML, juvenile myelomonocytic leukemia
- KO, knockout
- MAPK, mitogen-activated protein kinase
- NF-κB, nuclear factor-κB
- PI3K, phosphatidyl-inositol 3-kinase
- PTP, protein tyrosine phosphatase
- PTPN11
- RAS, rat sarcoma viral oncogene
- epithelium
- gastrointestinal cancer
- inflammation
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Affiliation(s)
| | - Nathalie Rivard
- Correspondence Address correspondence to: Nathalie Rivard, PhD, 3201, Jean Mignault, Sherbrooke, Quebec, Canada, J1E4K8.3201Jean Mignault, SherbrookeQuebecCanada, J1E4K8
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Doucette CD, Greenshields AL, Liwski RS, Hoskin DW. Piperine blocks interleukin-2-driven cell cycle progression in CTLL-2 T lymphocytes by inhibiting multiple signal transduction pathways. Toxicol Lett 2015; 234:1-12. [DOI: 10.1016/j.toxlet.2015.01.020] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2014] [Revised: 01/26/2015] [Accepted: 01/31/2015] [Indexed: 02/03/2023]
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McPherson RC, Konkel JE, Prendergast CT, Thomson JP, Ottaviano R, Leech MD, Kay O, Zandee SEJ, Sweenie CH, Wraith DC, Meehan RR, Drake AJ, Anderton SM. Epigenetic modification of the PD-1 (Pdcd1) promoter in effector CD4(+) T cells tolerized by peptide immunotherapy. eLife 2014; 3. [PMID: 25546306 PMCID: PMC4297948 DOI: 10.7554/elife.03416] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2014] [Accepted: 12/24/2014] [Indexed: 12/14/2022] Open
Abstract
Clinically effective antigen-based immunotherapy must silence antigen-experienced effector T cells (Teff) driving ongoing immune pathology. Using CD4+ autoimmune Teff cells, we demonstrate that peptide immunotherapy (PIT) is strictly dependent upon sustained T cell expression of the co-inhibitory molecule PD-1. We found high levels of 5-hydroxymethylcytosine (5hmC) at the PD-1 (Pdcd1) promoter of non-tolerant T cells. 5hmC was lost in response to PIT, with DNA hypomethylation of the promoter. We identified dynamic changes in expression of the genes encoding the Ten-Eleven-Translocation (TET) proteins that are associated with the oxidative conversion 5-methylcytosine and 5hmC, during cytosine demethylation. We describe a model whereby promoter demethylation requires the co-incident expression of permissive histone modifications at the Pdcd1 promoter together with TET availability. This combination was only seen in tolerant Teff cells following PIT, but not in Teff that transiently express PD-1. Epigenetic changes at the Pdcd1 locus therefore determine the tolerizing potential of TCR-ligation. DOI:http://dx.doi.org/10.7554/eLife.03416.001 The immune system protects the body from dangerous microbes and removes damaged cells. However, in some cases, the immune system can malfunction and attack healthy tissues, which can lead to type-1 diabetes, multiple sclerosis, and other autoimmune diseases. Many of the current treatments for these disorders suppress the immune system, which can make the individuals more susceptible to infections. It may be possible to treat autoimmune diseases using small pieces of protein—called peptides—that are based on proteins found on the cells that the immune system attacks by mistake. This strategy would target the specific immune cells that are malfunctioning, but allow the rest of the immune system to continue to work as normal. Peptide-based therapies for autoimmune diseases are currently being tested in clinical trials, and although the results look promising, it is not known precisely how they work. McPherson et al. used mice that develop a disease similar to multiple sclerosis because some of their immune cells, known as effector T cells, attack a protein found in the mouse brain called MBP. The mice were treated with a peptide based on part of MBP, which prevented them from developing the autoimmune disease. The success of the peptide therapy depended on the T cells producing large amounts of a protein called PD-1. This protein stops the T-cells from activating immune responses when they detect the MBP protein. The gene that makes PD-1 can have a methyl-tag—a chemical modification to DNA—which alters how much PD-1 is made in the T cells. When the gene has this methyl-tag, it can only be switched on for a short time to make a small amount of PD-1, which helps to control the immune responses activated by the T cell. However, when the methyl-tag was removed as a result of the peptide therapy the gene could be switched on for much longer, so that much more PD-1 was produced. This work helps us to understand how peptide therapy works and should improve the chances of using this therapy to successfully treat patients with autoimmune diseases. DOI:http://dx.doi.org/10.7554/eLife.03416.002
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Affiliation(s)
- Rhoanne C McPherson
- MRC Centre for Inflammation Research, University of Edinburgh, Edinburgh, United Kingdom
| | - Joanne E Konkel
- MRC Centre for Inflammation Research, University of Edinburgh, Edinburgh, United Kingdom
| | - Catriona T Prendergast
- MRC Centre for Inflammation Research, University of Edinburgh, Edinburgh, United Kingdom
| | - John P Thomson
- MRC Human Genetics Unit, Institute of Genetics and Molecular Medicine, University of Edinburgh, Edinburgh, United Kingdom
| | - Raffaele Ottaviano
- MRC Human Genetics Unit, Institute of Genetics and Molecular Medicine, University of Edinburgh, Edinburgh, United Kingdom
| | - Melanie D Leech
- MRC Centre for Inflammation Research, University of Edinburgh, Edinburgh, United Kingdom
| | - Oliver Kay
- MRC Centre for Inflammation Research, University of Edinburgh, Edinburgh, United Kingdom
| | - Stephanie E J Zandee
- MRC Centre for Inflammation Research, University of Edinburgh, Edinburgh, United Kingdom
| | - Claire H Sweenie
- MRC Centre for Inflammation Research, University of Edinburgh, Edinburgh, United Kingdom
| | - David C Wraith
- Department of Cellular and Molecular Medicine, University of Bristol, Bristol, United Kingdom
| | - Richard R Meehan
- MRC Human Genetics Unit, Institute of Genetics and Molecular Medicine, University of Edinburgh, Edinburgh, United Kingdom
| | - Amanda J Drake
- University/BHF Centre for Cardiovascular Science, University of Edinburgh, Edinburgh, United Kingdom
| | - Stephen M Anderton
- MRC Centre for Inflammation Research, University of Edinburgh, Edinburgh, United Kingdom
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21
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Kamiya N, Kim HKW, King PD. Regulation of bone and skeletal development by the SHP-2 protein tyrosine phosphatase. Bone 2014; 69:55-60. [PMID: 25178522 DOI: 10.1016/j.bone.2014.08.015] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/07/2014] [Revised: 08/15/2014] [Accepted: 08/22/2014] [Indexed: 01/06/2023]
Abstract
Src homology-2 protein tyrosine phosphatase (SHP-2) that is encoded by the PTPN11 gene in humans is an intracellular signaling molecule that couples growth factor receptors to activation of the Ras small GTP-binding protein that regulates cell growth, proliferation and differentiation. Germline mutations of PTPN11 are causative of Noonan syndrome and LEOPARD syndrome in humans in which there are recognized skeletal abnormalities that include growth retardation, spinal curvature and chest malformations. In addition, combined somatic and germline PTPN11 mutations have been shown to be responsible for a rare benign bone cartilaginous tumor disease known as metachondromatosis. In parallel, gene targeting studies performed in mice have revealed an essential role for SHP-2 as a regulator of bone and skeletal development. In this review the significance of these findings in mice to the understanding of the pathogenesis of skeletal abnormalities in humans with SHP-2 mutations is discussed.
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Affiliation(s)
- Nobuhiro Kamiya
- Center for Excellence in Hip Disorders, Texas Scottish Rite Hospital for Children, Dallas, TX 75219, USA; Orthopaedic Surgery, University of Texas Southwestern Medical Center, Dallas, TX 75390-8883, USA; Sports Medicine, Tenri University, Tenri, Nara 632-0071, Japan.
| | - Harry K W Kim
- Center for Excellence in Hip Disorders, Texas Scottish Rite Hospital for Children, Dallas, TX 75219, USA; Orthopaedic Surgery, University of Texas Southwestern Medical Center, Dallas, TX 75390-8883, USA.
| | - Philip D King
- Department of Microbiology and Immunology, University of Michigan Medical School, Ann Arbor, MI 48109-5620, USA.
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22
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Abstract
UNLABELLED Multiple sclerosis (MS) is an autoimmune neurological disease characterized by inflammatory demyelination with subsequent neuronal damage in the CNS. MS and its animal model, experimental autoimmune encephalomyelitis (EAE), have been thought as autoreactive Th1 and Th17 cell-mediated diseases. CD4(+) CD25(+) FoxP3(+) regulatory T-cell (Treg) plays a pivotal role in autoimmune tolerance, and tolerogenic dendritic cells (DCreg) drive the development of inducible Treg cells. Thus, a dysfunction in the development of Treg and DCreg leads to the development of autoimmune diseases. However, the factors that regulate Treg and DCreg are largely unknown. We recently showed that removal of midkine (MK) suppressed EAE due to an expansion of the Treg cell population as well as a decrease in the numbers of autoreactive Th1 and Th17 cells. MK decreased the Treg cell population by suppressing the phosphorylation of STAT5, which is essential for the expression of Foxp3, the master transcriptional factor of Treg cell differentiation. Furthermore, MK reduces the DCreg cell population by inhibiting the phosphorylation of STAT3, which is critical for DCreg development. Blockade of MK signalling by a specific RNA aptamer significantly elevated the population of DCreg and Treg cells and ameliorated EAE without detectable adverse effects. Therefore, the inhibition of MK may provide an effective therapeutic strategy against autoimmune diseases including MS. LINKED ARTICLES This article is part of a themed section on Midkine. To view the other articles in this section visit http://dx.doi.org/10.1111/bph.2014.171.issue-4.
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Affiliation(s)
- Hideyuki Takeuchi
- Department of Neuroimmunology, Research Institute of Environmental Medicine, Nagoya University, Nagoya, 464-8601, Japan
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23
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Kissick HT, Sanda MG, Dunn LK, Pellegrini KL, On ST, Noel JK, Arredouani MS. Androgens alter T-cell immunity by inhibiting T-helper 1 differentiation. Proc Natl Acad Sci U S A 2014; 111:9887-92. [PMID: 24958858 DOI: 10.1073/pnas.1402468111] [Citation(s) in RCA: 200] [Impact Index Per Article: 20.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
The hormonal milieu influences immune tolerance and the immune response against viruses and cancer, but the direct effect of androgens on cellular immunity remains largely uncharacterized. We therefore sought to evaluate the effect of androgens on murine and human T cells in vivo and in vitro. We found that murine androgen deprivation in vivo elicited RNA expression patterns conducive to IFN signaling and T-cell differentiation. Interrogation of mechanism showed that testosterone regulates T-helper 1 (Th1) differentiation by inhibiting IL-12-induced Stat4 phosphorylation: in murine models, we determined that androgen receptor binds a conserved region within the phosphatase, Ptpn1, and consequent up-regulation of Ptpn1 then inhibits IL-12 signaling in CD4 T cells. The clinical relevance of this mechanism, whereby the androgen milieu modulates CD4 T-cell differentiation, was ascertained as we found that androgen deprivation reduced expression of Ptpn1 in CD4 cells from patients undergoing androgen deprivation therapy for prostate cancer. Our findings, which demonstrate a clinically relevant mechanism by which androgens inhibit Th1 differentiation of CD4 T cells, provide rationale for targeting androgens to enhance CD4-mediated immune responses in cancer or, conversely, for modulating androgens to mitigate CD4 responses in disorders of autoimmunity.
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24
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Abstract
SIGNIFICANCE The protein tyrosine phosphatases (PTPs) are a family of proteins that play critical roles in cellular signaling and influence many aspects of human health and disease. Although a wealth of information has been collected about PTPs since their discovery, many questions regarding their regulation and function still remain. CRITICAL ISSUES Of particular importance are the elucidation of the biological substrates of individual PTPs and understanding of the chemical and biological basis for temporal and spatial resolution of PTP activity within a cell. RECENT ADVANCES Drawing from recent advances in both biology and chemistry, innovative approaches have been developed to study the intracellular biochemistry and physiology of PTPs. We provide a summary of PTP-tailored techniques and approaches, emphasizing methodologies to study PTP activity within a cellular context. We first provide a discussion of methods for identifying PTP substrates, including substrate-trapping mutants and synthetic peptide libraries for substrate selectivity profiling. We next provide an overview of approaches for monitoring intracellular PTP activity, including a discussion of mechanistic-based probes, gel-based assays, substrates that can be used intracellularly, and assays tied to cell growth. Finally, we review approaches used for monitoring PTP oxidation, a key regulatory pathway for these enzymes, discussing the biotin switch method and variants of this approach, along with affinity trapping techniques and probes designed to detect PTP oxidation. FUTURE DIRECTIONS Further development of approaches to investigate the intracellular PTP activity and functions will provide specific insight into their mechanisms of action and control of diverse signaling pathways.
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Affiliation(s)
- Stephanie M Stanford
- 1 Division of Cellular Biology, La Jolla Institute for Allergy and Immunology , La Jolla, California
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25
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Böhmer FD, Friedrich K. Protein tyrosine phosphatases as wardens of STAT signaling. JAKSTAT 2014; 3:e28087. [PMID: 24778927 DOI: 10.4161/jkst.28087] [Citation(s) in RCA: 58] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2013] [Revised: 02/03/2014] [Accepted: 02/03/2014] [Indexed: 02/07/2023] Open
Abstract
Signaling by signal transducers and activators of transcription (STATs) is controlled at many levels of the signaling cascade. Protein tyrosine phosphatases (PTPs) regulate STAT activation at several layers, including direct pSTAT dephosphorylation in both cytoplasm and nucleus. Despite the importance of this regulation mode, many aspects are still incompletely understood, e.g., the identity of PTPs acting on certain members of the STAT family. After a brief introduction into the STAT and PTP families, we discuss here the current knowledge on PTP mediated regulation of STAT activity, focusing on the interaction of individual STATs with specific PTPs. Finally, we highlight open questions and propose important tasks of future research.
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Affiliation(s)
- Frank-D Böhmer
- Institute of Molecular Cell Biology; CMB; Jena University Hospital; Jena, Germany
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26
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Lochab S, Pal P, Kapoor I, Kanaujiya JK, Sanyal S, Behre G, Trivedi AK. E3 ubiquitin ligase Fbw7 negatively regulates granulocytic differentiation by targeting G-CSFR for degradation. Biochim Biophys Acta 2013; 1833:2639-2652. [PMID: 23820376 DOI: 10.1016/j.bbamcr.2013.06.018] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/08/2013] [Revised: 06/10/2013] [Accepted: 06/21/2013] [Indexed: 11/30/2022]
Abstract
Tight control between activation and attenuation of granulocyte colony stimulating factor receptor (G-CSFR) signaling is essential to regulate survival, proliferation and differentiation of myeloid progenitor cells. Previous studies demonstrated negative regulation of G-CSFR through endosomal-lysosomal routing and ubiquitin-proteasome mediated degradation. However, very few E3 ubiquitin ligases are known to target G-CSFR for ubiquitin-proteasome pathway. Here we identified F-box and WD repeat domain-containing 7 (Fbw7), a substrate recognizing component of Skp-Cullin-F box (SCF) E3 ubiquitin Ligase physically associates with G-CSFR and promotes its ubiquitin-mediated proteasomal degradation. Our data shows that Fbw7 also interacts with and degrades G-CSFR-T718 (a truncated mutant of G-CSFR found in severe congenital neutropenia/acute myeloid leukemia (SCN/AML patients)) though at a quite slower rate compared to G-CSFR. We further show that glycogen synthase kinase 3 beta (GSK3β), like Fbw7 also targets G-CSFR and G-CSFR-T718 for degradation; however, Fbw7 and GSK3β are interdependent in targeting G-CSFR/G-CSFR-T718 for degradation because they are unable to degrade G-CSFR individually when either of them is knocked down. We further show that Fbw7 mediated downregulation of G-CSFR inhibits signal transducer and activator of transcription 3 (STAT3) phosphorylation which is required for G-CSF dependent granulocytic differentiation. In addition, our data also shows that inhibition of Fbw7 restores G-CSFR signaling leading to enhanced STAT3 activity resulting in massive granulocytic differentiation. These data indicate that Fbw7 together with GSK3β negatively regulates G-CSFR expression and its downstream signaling.
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Affiliation(s)
- Savita Lochab
- Drug Target Discovery and Development Division, CSIR-Central Drug Research Institute (CSIR-CDRI), Sector-10, Jankipuram Extension, Lucknow, 226031 UP, India
| | - Pooja Pal
- Drug Target Discovery and Development Division, CSIR-Central Drug Research Institute (CSIR-CDRI), Sector-10, Jankipuram Extension, Lucknow, 226031 UP, India
| | - Isha Kapoor
- Drug Target Discovery and Development Division, CSIR-Central Drug Research Institute (CSIR-CDRI), Sector-10, Jankipuram Extension, Lucknow, 226031 UP, India
| | - Jitendra Kumar Kanaujiya
- Drug Target Discovery and Development Division, CSIR-Central Drug Research Institute (CSIR-CDRI), Sector-10, Jankipuram Extension, Lucknow, 226031 UP, India
| | - Sabyasachi Sanyal
- Drug Target Discovery and Development Division, CSIR-Central Drug Research Institute (CSIR-CDRI), Sector-10, Jankipuram Extension, Lucknow, 226031 UP, India
| | - Gerhard Behre
- Division of Hematology and Oncology, University Hospital of Leipzig, Johannissallee 32A, 04103 Leipzig, Germany
| | - Arun Kumar Trivedi
- Drug Target Discovery and Development Division, CSIR-Central Drug Research Institute (CSIR-CDRI), Sector-10, Jankipuram Extension, Lucknow, 226031 UP, India.
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27
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Shatynski KE, Chen H, Kwon J, Williams MS. Decreased STAT5 phosphorylation and GATA-3 expression in NOX2-deficient T cells: role in T helper development. Eur J Immunol 2012; 42:3202-11. [PMID: 22930452 PMCID: PMC3691816 DOI: 10.1002/eji.201242659] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2012] [Revised: 07/15/2012] [Accepted: 08/20/2012] [Indexed: 01/26/2023]
Abstract
Absence of phagocyte NADPH oxidase (NOX2) activity causes chronic granulomatous disease (CGD), a primary immunodeficiency characterized by recurrent bacterial infections. In contrast to this innate immune deficit, CGD patients and animal models display a predisposition toward autoimmune disease and enhanced response to Helicobacter pylori and influenza virus infection. These data imply an altered, perhaps augmented, adaptive immune response in CGD. As previous data demonstrated functional NOX2 expression in T cells, our goal here was to determine if NOX2-deficient T cells are inherently altered in their responses. Activation of purified naive CD4(+) T cells from NOX2-deficient mice led to augmented IFN-γ and diminished IL-4 production and an increased ratio of expression of the T(H)1-specific transcription factor T-bet versus the T(H)2-specfic transcription factor GATA-3, consistent with a T(H)1 skewing of naïve T cells. Selective inhibition of TCR-induced STAT5 phosphorylation was identified as a potential mechanism for skewed T helper differentiation. Exposure to antioxidants inhibited, while pro-oxidants augmented T(H)2 cytokine secretion and STAT5 phosphorylation, supporting the redox dependence of these signaling changes. These data suggest that TCR-induced ROS generation from NOX2 activation can regulate the adaptive immune response in a T-cell-inherent fashion, and propose a possible role for redox signaling in T helper differentiation.
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MESH Headings
- Animals
- Bacterial Infections/enzymology
- Bacterial Infections/genetics
- Bacterial Infections/immunology
- Cell Differentiation/genetics
- Cell Differentiation/immunology
- GATA3 Transcription Factor/biosynthesis
- GATA3 Transcription Factor/genetics
- GATA3 Transcription Factor/immunology
- Granulomatous Disease, Chronic/genetics
- Granulomatous Disease, Chronic/immunology
- Granulomatous Disease, Chronic/metabolism
- Interferon-gamma/genetics
- Interferon-gamma/immunology
- Interferon-gamma/metabolism
- Interleukin-4/genetics
- Interleukin-4/immunology
- Interleukin-4/metabolism
- Membrane Glycoproteins/genetics
- Membrane Glycoproteins/immunology
- Membrane Glycoproteins/metabolism
- Mice
- Mice, Knockout
- NADPH Oxidase 2
- NADPH Oxidases/genetics
- NADPH Oxidases/immunology
- NADPH Oxidases/metabolism
- Oxidation-Reduction
- Phosphorylation/genetics
- Phosphorylation/immunology
- Reactive Oxygen Species/immunology
- Reactive Oxygen Species/metabolism
- Receptors, Antigen, T-Cell/genetics
- Receptors, Antigen, T-Cell/immunology
- Receptors, Antigen, T-Cell/metabolism
- STAT5 Transcription Factor/genetics
- STAT5 Transcription Factor/immunology
- STAT5 Transcription Factor/metabolism
- Signal Transduction/genetics
- Signal Transduction/immunology
- Th1 Cells/immunology
- Th1 Cells/metabolism
- Th1 Cells/pathology
- Th2 Cells/immunology
- Th2 Cells/metabolism
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Affiliation(s)
- Kristen E. Shatynski
- Department of Microbiology and Immunology, Center for Vascular and Inflammatory Diseases, University of Maryland School of Medicine, 800 W. Baltimore Street, Baltimore, MD 21201
| | - Haiyan Chen
- Department of Microbiology and Immunology, Center for Vascular and Inflammatory Diseases, University of Maryland School of Medicine, 800 W. Baltimore Street, Baltimore, MD 21201
| | - Jaeyul Kwon
- Laboratory of Host Defenses, National Institute of Allergy and Infectious Diseases, National Institutes of Health, 12441 Parklawn Drive, Rockville, MD 20852
| | - Mark S. Williams
- Department of Microbiology and Immunology, Center for Vascular and Inflammatory Diseases, University of Maryland School of Medicine, 800 W. Baltimore Street, Baltimore, MD 21201
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28
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Nabinger SC, Li XJ, Ramdas B, He Y, Zhang X, Zeng L, Richine B, Bowling JD, Fukuda S, Goenka S, Liu Z, Feng GS, Yu M, Sandusky GE, Boswell HS, Zhang ZY, Kapur R, Chan RJ. The protein tyrosine phosphatase, Shp2, positively contributes to FLT3-ITD-induced hematopoietic progenitor hyperproliferation and malignant disease in vivo. Leukemia 2013; 27:398-408. [PMID: 23103841 DOI: 10.1038/leu.2012.308] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Internal tandem duplications (ITDs) in the fms-like tyrosine kinase receptor (FLT3-ITDs) confer a poor prognosis in acute myeloid leukemia (AML). We hypothesized that increased recruitment of the protein tyrosine phosphatase, Shp2, to FLT3-ITDs contributes to FLT3 ligand (FL)-independent hyperproliferation and STAT5 activation. Co-immunoprecipitation demonstrated constitutive association of Shp2 with the FLT3-ITD, N51-FLT3, as well as with STAT5. Knockdown of Shp2 in Baf3/N51-FLT3 cells significantly reduced proliferation while having little effect on WT-FLT3-expressing cells. Consistently, mutation of N51-FLT3 tyrosine 599 to phenylalanine or genetic disruption of Shp2 in N51-FLT3-expressing bone marrow low-density mononuclear cells reduced proliferation and STAT5 activation. In transplants, genetic disruption of Shp2 in vivo yielded increased latency to and reduced severity of FLT3-ITD-induced malignancy. Mechanistically, Shp2 co-localizes with nuclear phospho-STAT5, is present at functional interferon-γ activation sites (GAS) within the BCL2L1 promoter, and positively activates the human BCL2L1 promoter, suggesting that Shp2 works with STAT5 to promote pro-leukemogenic gene expression. Further, using a small molecule Shp2 inhibitor, the proliferation of N51-FLT3-expressing bone marrow progenitors and primary AML samples was reduced in a dose-dependent manner. These findings demonstrate that Shp2 positively contributes to FLT3-ITD-induced leukemia and suggest that Shp2 inhibition may provide a novel therapeutic approach to AML.
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29
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Wu X, Guo W, Wu L, Gu Y, Gu L, Xu S, Wu X, Shen Y, Ke Y, Tan R, Sun Y, Xu Q. Selective sequestration of STAT1 in the cytoplasm via phosphorylated SHP-2 ameliorates murine experimental colitis. J Immunol 2012; 189:3497-507. [PMID: 22942432 DOI: 10.4049/jimmunol.1201006] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
The side effects of current immunosuppressive drugs have impeded the development of therapies for immune diseases. Selective regulation of STAT signaling is an attractive strategy for treating immune disorders. In this study, we used a small-molecule compound to explore possible means of targeting STAT1 for the treatment of Th1-mediated inflammation. Selective regulation of STAT1 signaling in T cells from C57BL/6 mice was accomplished using fusaruside, a small-molecule compound that triggers the tyrosine phosphorylation of Src homology 2-containing protein tyrosine phosphatase 2 (SHP-2). The interaction of tyrosine phosphorylated SHP-2 (pY-SHP-2) with cytosolic STAT1 prevented the recruitment of STAT1 to IFN-γR and specifically inhibited STAT1 signaling, resulting in a reduction in Th1 cytokine production and an improvement in 2, 4, 6-trinitrobenzene sulfonic acid-induced colitis in mice. Blocking the pY-SHP-2-STAT1 interaction, with SHP-2 inhibitor NSC-87877 or using T cells from conditional SHP-2 knockout mice, reversed the effects of fusaruside, resulting in STAT1 activation and worsened colitis. The fusaruside-induced ability of pY-SHP-2 to selectively sequestrate STAT1 from recruitment to the receptor is independent of its function as a phosphatase, demonstrating a novel role for SHP-2 in regulating both STAT1 signaling and Th1-type immune responses. These findings could lead to increased options for the treatment of Crohn's disease and other Th1-mediated inflammatory diseases.
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Affiliation(s)
- Xingxin Wu
- State Key Laboratory of Pharmaceutical Biotechnology, School of Life Sciences, Nanjing University, Nanjing 210093, China
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30
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Chueh FY, Yu CL. Engagement of T-cell antigen receptor and CD4/CD8 co-receptors induces prolonged STAT activation through autocrine/paracrine stimulation in human primary T cells. Biochem Biophys Res Commun 2012; 426:242-6. [PMID: 22935418 DOI: 10.1016/j.bbrc.2012.08.074] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2012] [Accepted: 08/15/2012] [Indexed: 01/27/2023]
Abstract
Signal transducer and activator of transcription (STAT) proteins are key signaling molecules in response to cytokines and in regulating T cell biology. However, there are contradicting reports on whether STAT is involved in T-cell antigen receptor (TCR) signaling. To better define the role of STAT in TCR signaling, we activated the CD4/CD8-associated Lck kinase by co-crosslinking TCR and CD4/CD8 co-receptors in human peripheral blood T cells. Sequential STAT1, STAT3 and STAT5 activation was observed 1 h after TCR stimulation suggesting that STAT proteins are not the immediate targets in the TCR complex. We further identified interferon-γ as the key cytokine in STAT1 activation upon TCR engagement. In contrast to transient STAT activation in cytokine response, this autocrine/paracrine-induced STAT activation was sustained. It correlated with the absence of two suppressors of cytokine signaling (SOCS) proteins, SOCS3 and cytokine-inducible SH2 containing protein that are negative feedback regulators of STAT signaling. Moreover, enforced expression of SOCS3 inhibited tyrosine phosphorylation of zeta-associated protein kinase of 70 kD in TCR-stimulated human Jurkat T cells. This is the first report demonstrating delayed and prolonged STAT activation coordinated with the loss of SOCS expression in human primary T cells after co-crosslinking of TCR and CD4/CD8 co-receptors.
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Affiliation(s)
- Fu-Yu Chueh
- Department of Microbiology and Immunology, H.M. Bligh Cancer Research Laboratories, Chicago Medical School, Rosalind Franklin University of Medicine and Science, North Chicago, IL 60064, USA
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31
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Buet D, Gallais I, Lauret E, Denis N, Lombard B, Guillonneau F, Kosmider O, Loew D, Dusanter-Fourt I, Guillouf C, Mayeux P, Moreau-Gachelin F. Cotargeting signaling pathways driving survival and cell cycle circumvents resistance to Kit inhibitors in leukemia. Blood 2012; 119:4228-41. [PMID: 22438255 DOI: 10.1182/blood-2011-07-368316] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
Oncogenic mutations leading to persistent kinase activities are associated with malignancies. Therefore, deciphering the signaling networks downstream of these oncogenic stimuli remains a challenge to gather insights into targeted therapy. To elucidate the biochemical networks connecting the Kit mutant to leukemogenesis, in the present study, we performed a global profiling of tyrosine-phosphorylated proteins from mutant Kit-driven murine leukemia proerythroblasts and identified Shp2 and Stat5 as proximal effectors of Kit. Shp2 or Stat5 gene depletion by sh-RNA, combined with pharmacologic inhibition of PI3kinase or Mek/Erk activities, revealed 2 distinct and independent signaling pathways contributing to malignancy. We demonstrate that cell survival is driven by the Kit/Shp2/Ras/Mek/Erk1/2 pathway, whereas the G(1)/S transition during the cell cycle is accelerated by both the Kit/Stat5 and Kit/PI3K/Akt pathways. The combined use of the clinically relevant drugs NVP-BEZ235, which targets the cell cycle, and Obatoclax, which targets survival, demonstrated synergistic effects to inhibit leukemia cell growth. This synergy was confirmed with a human mast leukemia cell line (HMC-1.2) that expresses mutant Kit. The results of the present study using liquid chromatography/tandem mass spectrometry analysis have elucidated signaling networks downstream of an oncogenic kinase, providing a molecular rationale for pathway-targeted therapy to treat cancer cells refractory to tyrosine kinase inhibitors.
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32
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Huang CY, Lin YC, Hsiao WY, Liao FH, Huang PY, Tan TH. DUSP4 deficiency enhances CD25 expression and CD4+ T-cell proliferation without impeding T-cell development. Eur J Immunol 2011; 42:476-88. [PMID: 22101742 DOI: 10.1002/eji.201041295] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2011] [Revised: 09/30/2011] [Accepted: 11/07/2011] [Indexed: 12/26/2022]
Abstract
The differentiation and activation of T cells are critically modulated by MAP kinases, which are in turn feed-back regulated by dual-specificity phosphatases (DUSPs) to determine the duration and magnitude of MAP kinase activation. DUSP4 (also known as MKP2) is a MAP kinase-induced DUSP member that is dynamically expressed during thymocyte differentiation. We generated DUSP4-deficient mice to study the function of DUSP4 in T-cell development and activation. Our results show that thymocyte differentiation and activation-induced MAP kinase phosphorylation were comparable between DUSP4-deficient and WT mice. Interestingly, activated DUSP4(-/-) CD4(+) T cells were hyperproliferative while DUSP4(-/-) CD8(+) T cells proliferated normally. Further mechanistic studies suggested that the hyperproliferation of DUSP4(-/-) CD4(+) T cells resulted from enhanced CD25 expression and IL-2 signaling through increased STAT5 phosphorylation. Immunization of DUSP4(-/-) mice recapitulated the T-cell hyperproliferation phenotype in antigen recall responses, while the profile of Th1/Th2-polarized antibody production was not altered. Overall, these results suggest that other DUSPs may compensate for DUSP4 deficiency in T-cell development, MAP kinase regulation, and Th1/Th2-mediated antibody responses. More importantly, our data indicate that DUSP4 suppresses CD4(+) T-cell proliferation through novel regulations in STAT5 phosphorylation and IL-2 signaling.
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Affiliation(s)
- Ching-Yu Huang
- Immunology Research Center, National Health Research Institutes, Zhunan, Miaoli County, Taiwan.
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Than TA, Ogino T, Hosako M, Omori M, Tsuchiyama J, Okada S. Physiological Oxidants Induce Apoptosis and Cell Cycle Arrest in a Multidrug-resistant Natural Killer Cell Line, NK-YS. Leuk Lymphoma 2011; 44:2109-16. [PMID: 14959856 DOI: 10.1080/1042819031000119271] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
Natural-killer (NK) cell-derived malignant tumors, such as angiocentric lymphoma, is often resistant to various chemotherapeutic agents and follows an aggressive clinical course. We report the effects of physiological oxidants (hydrogen peroxide, H2O2; sodium hypochlorite, NaOCl and monochloramine, NH2Cl) on the cell growth and cell death in a multidrug-resistant NK tumor cell line, NK-YS. Among the oxidants tested, NH2Cl was most cytotoxic, in which more than 90% of the cells died at 150 nmol/1 x 10(6) cells. H2O2 was less cytotoxic, whereas NaOCl showed no significant cell death at this dose. The cell death induced by NH2Cl was accompanied by DNA cleavage and caspase activation, which suggested apoptosis. In addition, lower dose of NH2Cl (70 nmol/1 x 10(6) cells) retarded cell growth and inhibited the cell cycle transition from G1 to S. This cell cycle arrest accompanied a decrease in the phosphorylation of retinoblastoma tumor suppressor protein at serine 795. These observations suggest that NH2Cl may induce apoptotic cell death and growth arrest in multidrug-resistant NK cell tumors.
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Affiliation(s)
- Tin Aung Than
- Department of Pathological Research, Okayama University Graduate School of Medicine and Dentistry, 2-5-1 Shikata, Okayama 700-8558, Japan
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Bachmann J, Raue A, Schilling M, Böhm ME, Kreutz C, Kaschek D, Busch H, Gretz N, Lehmann WD, Timmer J, Klingmüller U. Division of labor by dual feedback regulators controls JAK2/STAT5 signaling over broad ligand range. Mol Syst Biol 2011; 7:516. [PMID: 21772264 DOI: 10.1038/msb.2011.50] [Citation(s) in RCA: 92] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2010] [Accepted: 06/10/2011] [Indexed: 02/06/2023] Open
Abstract
Cellular signal transduction is governed by multiple feedback mechanisms to elicit robust cellular decisions. The specific contributions of individual feedback regulators, however, remain unclear. Based on extensive time-resolved data sets in primary erythroid progenitor cells, we established a dynamic pathway model to dissect the roles of the two transcriptional negative feedback regulators of the suppressor of cytokine signaling (SOCS) family, CIS and SOCS3, in JAK2/STAT5 signaling. Facilitated by the model, we calculated the STAT5 response for experimentally unobservable Epo concentrations and provide a quantitative link between cell survival and the integrated response of STAT5 in the nucleus. Model predictions show that the two feedbacks CIS and SOCS3 are most effective at different ligand concentration ranges due to their distinct inhibitory mechanisms. This divided function of dual feedback regulation enables control of STAT5 responses for Epo concentrations that can vary 1000-fold in vivo. Our modeling approach reveals dose-dependent feedback control as key property to regulate STAT5-mediated survival decisions over a broad range of ligand concentrations.
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Larbi A, Pawelec G, Wong SC, Goldeck D, Tai JJY, Fulop T. Impact of age on T cell signaling: a general defect or specific alterations? Ageing Res Rev 2011; 10:370-8. [PMID: 20933612 DOI: 10.1016/j.arr.2010.09.008] [Citation(s) in RCA: 64] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2010] [Revised: 09/22/2010] [Accepted: 09/24/2010] [Indexed: 01/09/2023]
Abstract
Decreased immune responsiveness associated with aging is generally termed "immunosenescence". Several theories have been proposed to explain age-related declines in immune responses. Here, we will focus on and describe potential defects in T cell signal transduction from the membrane to the nucleus, leading to changes in the type, intensity and duration of the response as a major factor contributing to immunosenescence. We will first detail T cell signaling through the T cell receptor (TCR), CD28 and IL-2 receptor (IL-2R) and then discuss the observed age-related alterations to these signaling pathways. The role of membrane rafts in T cell signaling and T cell aging will be described. These factors will be considered in the context of the notion that age-related changes to T cell signaling may be attributed to changes in the functionality of the T cells due to shifts in T cell subpopulations with age. For this reason, we conclude by highlighting the application of multiparametric signaling analysis in leukocyte subsets using flow cytometry as a means to obtain a clearer picture with respect to age-related changes to immune signaling.
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Chueh FY, Leong KF, Cronk RJ, Venkitachalam S, Pabich S, Yu CL. Nuclear localization of pyruvate dehydrogenase complex-E2 (PDC-E2), a mitochondrial enzyme, and its role in signal transducer and activator of transcription 5 (STAT5)-dependent gene transcription. Cell Signal 2011; 23:1170-8. [PMID: 21397011 DOI: 10.1016/j.cellsig.2011.03.004] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2010] [Revised: 02/28/2011] [Accepted: 03/03/2011] [Indexed: 10/18/2022]
Abstract
STAT (signal transducer and activator of transcription) proteins play a critical role in cellular response to a wide variety of cytokines and growth factors by regulating specific nuclear genes. STAT-dependent gene transcription can be finely tuned through the association with co-factors in the nucleus. We showed previously that STAT5 (including 5a and 5b) specifically interacts with a mitochondrial enzyme PDC-E2 (E2 subunit of pyruvate dehydrogenase complex) in both leukemic T cells and cytokine-stimulated cells. However, the functional significance of this novel association remains largely unknown. Here we report that PDC-E2 may function as a co-activator in STAT5-dependent nuclear gene expression. Subcellular fractionation analysis revealed that a substantial amount of PDC-E2 was constitutively present in the nucleus of BaF3, an interleukin-3 (IL-3)-dependent cell line. IL-3-induced tyrosine-phosphorylated STAT5 associated with nuclear PDC-E2 in co-immunoprecipitation analysis. These findings were confirmed by confocal immunofluorescence microscopy showing constant nuclear localization of PDC-E2 and its co-localization with STAT5 after IL-3 stimulation. Similar to mitochondrial PDC-E2, nuclear PDC-E2 was lipoylated and associated with PDC-E1. Overexpression of PDC-E2 in BaF3 cells augmented IL-3-induced STAT5 activity as measured by reporter assay with consensus STAT5-binding sites. Consistent with the reporter data, PDC-E2 overexpression in BaF3 cells led to elevated mRNA levels of endogenous SOCS3 (suppressor of cytokine signaling 3) gene, a known STAT5 target. We further identified two functional STAT5-binding sites in the SOCS3 gene promoter important for its IL-3-inducibility. The observation that both cis-acting elements were essential to detect the stimulatory effect by PDC-E2 strongly supports the role of PDC-E2 in up-regulating the transactivating ability of STAT5. All together, our results reveal a novel function of PDC-E2 in the nucleus. It also raises the possibility of nuclear-mitochondrial crosstalk through the interaction between STAT5 and PDC-E2.
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Affiliation(s)
- Fu-Yu Chueh
- Department of Microbiology and Immunology, H. M. Bligh Cancer Research Laboratories, Chicago Medical School, Rosalind Franklin University of Medicine and Science, 3333 Green Bay Road, North Chicago, IL 60064, USA
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Dhennin-Duthille I, Nyga R, Yahiaoui S, Gouilleux-Gruart V, Régnier A, Lassoued K, Gouilleux F. The tumor suppressor hTid1 inhibits STAT5b activity via functional interaction. J Biol Chem 2010; 286:5034-42. [PMID: 21106534 DOI: 10.1074/jbc.m110.155903] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
STAT5a and -5b (signal transducers and activators of transcription 5a and 5b) proteins play an essential role in hematopoietic cell proliferation and survival and are frequently constitutively active in hematologic neoplasms and solid tumors. Because STAT5a and STAT5b differ mainly in the carboxyl-terminal transactivation domain, we sought to identify new proteins that bind specifically to this domain by using a bacterial two-hybrid screening. We isolated hTid1, a human DnaJ protein that acts as a tumor suppressor in various solid tumors. hTid1 interacts specifically with STAT5b but not with STAT5a in hematopoietic cell lines. This interaction involves the cysteine-rich region of the hTid1 DnaJ domain. We also demonstrated that hTid1 negatively regulates the expression and transcriptional activity of STAT5b and suppresses the growth of hematopoietic cells transformed by an oncogenic form of STAT5b. Our findings define hTid1 as a novel partner and negative regulator of STAT5b.
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Affiliation(s)
- Isabelle Dhennin-Duthille
- INSERM, U925, Université de Picardie Jules Verne, UFR de Médecine, 3 Rue des Louvels, 80036 Amiens, France
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38
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Chueh FY, Leong KF, Yu CL. Mitochondrial translocation of signal transducer and activator of transcription 5 (STAT5) in leukemic T cells and cytokine-stimulated cells. Biochem Biophys Res Commun 2010; 402:778-83. [PMID: 21036145 DOI: 10.1016/j.bbrc.2010.10.112] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2010] [Accepted: 10/24/2010] [Indexed: 01/07/2023]
Abstract
Signal transducers and activators of transcription (STATs) were first identified as key signaling molecules in response to cytokines. Constitutive STAT activation also has been widely implicated in oncogenesis. We analyzed STAT5-associated proteins in a leukemic T cell line LSTRA, which exhibits constitutive tyrosine phosphorylation and activation of STAT5. A cellular protein was found to specifically interact with STAT5 in LSTRA cells by co-immunoprecipitation. Sequencing analysis and subsequent immunoblotting confirmed the identity of this STAT5-associated protein as the E2 component of mitochondrial pyruvate dehydrogenase complex (PDC-E2). Consistent with this interaction, both subcellular fractionation and immunofluorescence microscopy revealed mitochondrial localization of STAT5 in LSTRA cells. Mitochondrial localization of tyrosine-phosphorylated STAT5 also occurred in cytokine-stimulated cells. A time course experiment further demonstrated the transient kinetics of STAT5 mitochondrial translocation after cytokine stimulation. In contrast, cytokine-induced STAT1 and STAT3 activation did not result in their translocation into mitochondria. Furthermore, we showed that mitochondrial STAT5 bound to the D-loop regulatory region of mitochondrial DNA in vitro. It suggests a potential role of STAT5 in regulating the mitochondrial genome. Proliferative metabolism toward aerobic glycolysis is well known in cancer cells as the Warburg effect and is also observed in cytokine-stimulated cells. Our novel findings of cytokine-induced STAT5 translocation into mitochondria and its link to oncogenesis provide important insights into the underlying mechanisms of this characteristic metabolic shift.
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Affiliation(s)
- Fu-Yu Chueh
- Department of Microbiology and Immunology, Chicago Medical School, Rosalind Franklin University of Medicine and Science, North Chicago, IL 60064, USA
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39
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Abstract
Signal transducers and activators of transcription (STAT)1 is the key to the sequential control of Madin-Darby canine kidney tubulogenesis. Loss of STAT1 prevents redifferentiation. Constitutively active STAT1 is sufficient to restore cord formation but not mature lumens. These data suggest that STAT1 is necessary for the redifferentiation phase of tubulogenesis and that mature lumenogenesis requires a distinct signal. Tubule formation in vitro using Madin-Darby canine kidney (MDCK) epithelial cells consists mainly of two processes. First, the cells undergo a partial epithelial–mesenchymal transition (pEMT), losing polarity and migrating. Second, the cells redifferentiate, forming cords and then tubules with continuous lumens. We have shown previously that extracellular signal-regulated kinase activation is required for pEMT. However, the mechanism of how the pEMT phase is turned off and the redifferentiation phase is initiated is largely unknown. To address the central question of the sequential control of these two phases, we used MDCK cells grown as cysts and treated with hepatocyte growth factor to model tubulogenesis. We show that signal transducer and activator of transcription (STAT)1 controls the sequential progression from the pEMT phase to the redifferentiation phase. Loss of STAT1 prevents redifferentiation. Constitutively active STAT1 allows redifferentiation to occur even when cells are otherwise prevented from progressing beyond the pEMT phase by exogenous activation of Raf. Moreover, tyrosine phosphorylation defective STAT1 partially restored cord formation in such cells, suggesting that STAT1 functions in part as nonnuclear protein mediating signal transduction in this process. Constitutively active or inactive forms of STAT1 did not promote lumen maturation, suggesting this requires a distinct signal.
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Affiliation(s)
- Minji Kim
- Department of Anatomy, University of California-San Francisco, San Francisco, CA 94158, USA
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40
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Ruela-de-Sousa RR, Queiroz KCS, Peppelenbosch MP, Fuhler GM. Reversible phosphorylation in haematological malignancies: potential role for protein tyrosine phosphatases in treatment? Biochim Biophys Acta Rev Cancer 2010; 1806:287-303. [PMID: 20659529 DOI: 10.1016/j.bbcan.2010.07.007] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2010] [Revised: 07/16/2010] [Accepted: 07/20/2010] [Indexed: 01/12/2023]
Abstract
Most aspects of leukocyte physiology are under the control of reversible tyrosine phosphorylation. It is clear that excessive phosphorylation of signal transduction elements is a pivotal element of many different pathologies including haematological malignancies and accordingly, strategies that target such phosphorylation have clinically been proven highly successful for treatment of multiple types of leukemias and lymphomas. Cellular phosphorylation status is dependent on the resultant activity of kinases and phosphatases. The cell biology of the former is now well understood; for most cellular phosphoproteins we now know the kinases responsible for their phosphorylation and we understand the principles of their aberrant activity in disease. With respect to phosphatases, however, our knowledge is much patchier. Although the sequences of whole genomes allow us to identify phosphatases using in silico methodology, whereas transcription profiling allows us to understand how phosphatase expression is regulated during disease, most functional questions as to substrate specificity, dynamic regulation of phosphatase activity and potential for therapeutic intervention are still to a large degree open. Nevertheless, recent studies have allowed us to make meaningful statements on the role of tyrosine phosphatase activity in the three major signaling pathways that are commonly affected in leukemias, i.e. the Ras-Raf-ERK1/2, the Jak-STAT and the PI3K-PKB-mTOR pathways. Lessons learned from these pathways may well be applicable elsewhere in leukocyte biology as well.
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Affiliation(s)
- Roberta R Ruela-de-Sousa
- Center for Experimental and Molecular Medicine, Academic Medical Center, Meibergdreef 9 1105 AZ Amsterdam, The Netherlands
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Abstract
Adaptive T cell responses are critical for controlling infections with viruses such as HIV, HBV, and HCV. However, these responses must be carefully regulated because overly vigorous T cell activation can lead to excessive host tissue damage. T cell expression of the inhibitory receptor programmed death-1 (PD-1) and inhibition of effector T cells (Teffs) by CD4+Foxp3+Tregs are among the many described mechanisms for achieving a balanced immune response. Although the signals that contribute to Teff function are well understood, less is known about the signals controlling Tregs. In this issue of the JCI, Franceschini et al. extend our understanding of how Tregs are modulated during chronic HCV infection by demonstrating that Treg proliferation is inhibited by PD-1 and that this inhibition is mediated by a potentially novel mechanism involving the prevention of IL-2-driven STAT-5phosphorylation.
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Affiliation(s)
- Henry Radziewicz
- Emory Vaccine Center, Department of Microbiology and Immunology, Emory University School of Medicine, 954 Gatewood Road NE, Atlanta, GA 30329, USA
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Catalfamo M, Di Mascio M, Hu Z, Srinivasula S, Thaker V, Adelsberger J, Rupert A, Baseler M, Tagaya Y, Roby G, Rehm C, Follmann D, Lane HC. HIV infection-associated immune activation occurs by two distinct pathways that differentially affect CD4 and CD8 T cells. Proc Natl Acad Sci U S A 2008; 105:19851-6. [PMID: 19060209 DOI: 10.1073/pnas.0810032105] [Citation(s) in RCA: 101] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023] Open
Abstract
HIV infection is characterized by a brisk immune activation that plays an important role in the CD4 depletion and immune dysfunction of patients with AIDS. The mechanism underlying this activation is poorly understood. In the current study, we tested the hypothesis that this activation is the net product of two distinct pathways: the inflammatory response to HIV infection and the homeostatic response to CD4 T cell depletion. Using ex vivo BrdU incorporation of PBMCs from 284 patients with different stages of HIV infection, we found that CD4 proliferation was better predicted by the combination of CD4 depletion and HIV viral load (R(2) = 0.375, P < 0.001) than by either parameter alone (CD4 T cell counts, R(2) = 0.202, P < 0.001; HIV viremia, R(2) = 0.302, P < 0.001). Interestingly, CD8 T cell proliferation could be predicted by HIV RNA levels alone (R(2) = 0.334, P < 0.001) and this predictive value increased only slightly (R(2) = 0.346, P < 0.001) when CD4 T cell depletion was taken into account. Consistent with the hypothesis that CD4 T cell proliferation is driven by IL-7 as a homeostatic response to CD4 T cell depletion, levels of phosphorylated STAT-5 were found to be elevated in naive subsets of CD4 and CD8 T cells from patients with HIV infection and in the central memory subset of CD4 T cells. Taken together these data demonstrate that at least two different pathways lead to immune activation of T cells in patients with HIV infection and these pathways differentially influence CD4 and CD8 T cell subsets.
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Abstract
The Janus kinase (JAK)/signal transducer and activator of transcription (STAT) pathway is crucial in controlling cellular activities in response to extracellular cytokines. Dysfunctions of the JAK/STAT pathway result in various hematopoietic and immune disorders. The central events in regulating this pathway are tyrosine phosphorylation and dephosphorylation of the signaling components, which are carried out by protein tyrosine kinases and protein tyrosine phosphatases (PTP), respectively. Here, we review recent advances in the regulatory roles of PTPs, in particular, SHP2 phosphatase, in the JAK/STAT signaling pathway.
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Affiliation(s)
- Dan Xu
- Department of Medicine, Division of Hematology/Oncology, Case Comprehensive Cancer Center, Case Western Reserve University, Cleveland, Ohio 44106, USA
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45
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Abstract
Protein-tyrosine phosphatases are tightly controlled by various mechanisms, ranging from differential expression in specific cell types to restricted subcellular localization, limited proteolysis, post-translational modifications affecting intrinsic catalytic activity, ligand binding and dimerization. Here, we review the regulatory mechanisms found to control the classical protein-tyrosine phosphatases.
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Wang J, Takeuchi H, Sonobe Y, Jin S, Mizuno T, Miyakawa S, Fujiwara M, Nakamura Y, Kato T, Muramatsu H, Muramatsu T, Suzumura A. Inhibition of midkine alleviates experimental autoimmune encephalomyelitis through the expansion of regulatory T cell population. Proc Natl Acad Sci U S A 2008; 105:3915-20. [PMID: 18319343 DOI: 10.1073/pnas.0709592105] [Citation(s) in RCA: 89] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
CD4(+)CD25(+) regulatory T (Treg) cells are crucial mediators of autoimmune tolerance. The factors that regulate Treg cells, however, are largely unknown. Here, we show that deficiency in midkine (MK), a heparin-binding growth factor involved in oncogenesis, inflammation, and tissue repair, attenuated experimental autoimmune encephalomyelitis (EAE) because of an expansion of the Treg cell population in peripheral lymph nodes and decreased numbers of autoreactive T-helper type 1 (T(H)1) and T(H)17 cells. MK decreased the Treg cell population ex vivo in a dose-dependent manner by suppression of STAT5 phosphorylation that is essential for Foxp3 expression. Moreover, administration of anti-MK RNA aptamers significantly expanded the Treg cell population and alleviated EAE symptoms. These observations indicate that MK serves as a critical suppressor of Treg cell expansion, and inhibition of MK using RNA aptamers may provide an effective therapeutic strategy against autoimmune diseases, including multiple sclerosis.
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Kontaridis MI, Yang W, Bence KK, Cullen D, Wang B, Bodyak N, Ke Q, Hinek A, Kang PM, Liao R, Neel BG. Deletion of Ptpn11 (Shp2) in cardiomyocytes causes dilated cardiomyopathy via effects on the extracellular signal-regulated kinase/mitogen-activated protein kinase and RhoA signaling pathways. Circulation 2008; 117:1423-35. [PMID: 18316486 DOI: 10.1161/circulationaha.107.728865] [Citation(s) in RCA: 70] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
BACKGROUND Heart failure is the leading cause of death in the United States. By delineating the pathways that regulate cardiomyocyte function, we can better understand the pathogenesis of cardiac disease. Many cardiomyocyte signaling pathways activate protein tyrosine kinases. However, the role of specific protein tyrosine phosphatases (PTPs) in these pathways is unknown. METHODS AND RESULTS Here, we show that mice with muscle-specific deletion of Ptpn11, the gene encoding the SH2 domain-containing PTP Shp2, rapidly develop a compensated dilated cardiomyopathy without an intervening hypertrophic phase, with signs of cardiac dysfunction appearing by the second postnatal month. Shp2-deficient primary cardiomyocytes are defective in extracellular signal-regulated kinase/mitogen-activated protein kinase (Erk/MAPK) activation in response to a variety of soluble agonists and pressure overload but show hyperactivation of the RhoA signaling pathway. Treatment of primary cardiomyocytes with Erk1/2- and RhoA pathway-specific inhibitors suggests that both abnormal Erk/MAPK and RhoA activities contribute to the dilated phenotype of Shp2-deficient hearts. CONCLUSIONS Our results identify Shp2 as the first PTP with a critical role in adult cardiac function, indicate that in the absence of Shp2 cardiac hypertrophy does not occur in response to pressure overload, and demonstrate that the cardioprotective role of Shp2 is mediated via control of both the Erk/MAPK and RhoA signaling pathways.
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Affiliation(s)
- Maria I Kontaridis
- Cancer Biology Program, Department of Medicine, Beth Israel Deaconess Medical Center, NRB, Room 1036, 77 Ave Louis Pasteur, Boston, MA 02115, USA.
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Araki T, Langenick J, Gamper M, Firtel RA, Williams JG. Evidence that DIF-1 and hyper-osmotic stress activate a Dictyostelium STAT by inhibiting a specific protein tyrosine phosphatase. Development 2008; 135:1347-53. [PMID: 18305004 DOI: 10.1242/dev.009936] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
STATc becomes tyrosine phosphorylated and accumulates in the nucleus when Dictyostelium cells are exposed to the prestalk cell inducer Differentiation inducing factor 1 (DIF-1), or are subjected to hyper-osmotic stress. We show that the protein tyrosine phosphatase PTP3 interacts directly with STATc and that STATc is refractory to activation in PTP3 overexpressing cells. Conversely, overexpression of a dominant inhibitor of PTP3 leads to constitutive tyrosine phosphorylation and ectopic nuclear localisation of STATc. Treatment of cells with DIF-1 or exposure to hyper-osmotic stress induces a decrease in biochemically assayable PTP3 activity and both agents also induce serine-threonine phosphorylation of PTP3. These observations suggest a novel mode of STAT activation, whereby serine-threonine phosphorylation of a cognate protein tyrosine phosphatase results in the inhibition of its activity, shifting the phosphorylation-dephosphorylation equilibrium in favour of phosphorylation.
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Affiliation(s)
- Tsuyoshi Araki
- University of Dundee, College of Life Sciences, Dow Street, Dundee DD1 5EH, UK
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49
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Roubelakis MG, Martin-Rendon E, Tsaknakis G, Stavropoulos A, Watt SM. The murine ortholog of the SHP-2 binding molecule, PZR accelerates cell migration on fibronectin and is expressed in early embryo formation. J Cell Biochem 2008; 102:955-69. [PMID: 17440960 DOI: 10.1002/jcb.21334] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
The human P zero-related protein (hPZR) has a unique function in regulating cell migration. This activity is dependent on both its cytoplasmic immunoreceptor tyrosine inhibitory motif (ITIM) and its interaction with the tyrosine protein phosphatase, src homology phosphatase-2 (SHP-2). Here, using in silico and cDNA cloning approaches, we identify the murine ITIM-containing hPZR ortholog, mPZR, together with its ITIM-less isoform, mPZRb. We demonstrate that, like hPZR, these type 1 integral murine transmembrane isoforms are derived by differential splicing from a single gene transcription unit on mouse chromosome 1, and differ only in the sequence of their cytoplasmic domains. Importantly, mPZR mimicks hPZR functionally by accelerating SHP-2-mediated cell migration on fibronectin. Interestingly, we further demonstrate that although neither mPZR nor mPZRb is expressed in murine pluripotent embryonic stem cells, they first appear at approximately day 3 of blastocyst formation in vivo and of embryoid body formation in vitro. These studies thus provide the basis for defining the function of the mPZR isoforms in vivo, particularly with respect to their roles in regulating SHP-2-dependent cell migration during development.
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Affiliation(s)
- Maria G Roubelakis
- Stem Cell Research Laboratory, National Blood Service, NHS Blood and Transplant Authority, Oxford OX3 5BG, UK.
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50
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Hoyt R, Zhu W, Cerignoli F, Alonso A, Mustelin T, David M. Cutting edge: selective tyrosine dephosphorylation of interferon-activated nuclear STAT5 by the VHR phosphatase. J Immunol 2007; 179:3402-6. [PMID: 17785772 PMCID: PMC2770724 DOI: 10.4049/jimmunol.179.6.3402] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
Cytokine-induced tyrosine phosphorylation of the transcription factor STAT5 is required for its transcriptional activity. In this article we show that the small dual-specificity phosphatase VHR selectively dephosphorylates IFN-alpha- and beta-activated, tyrosine-phosphorylated STAT5, leading to the subsequent inhibition of STAT5 function. Phosphorylation of VHR at Tyr(138) was required for its phosphatase activity toward STAT5. In addition, the Src homology 2 domain of STAT5 was required for the effective dephosphorylation of STAT5 by VHR. The tyrosine kinase Tyk2, which mediates the phosphorylation of STAT5, was also responsible for the phosphorylation of VHR at Tyr(138).
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Affiliation(s)
- Richard Hoyt
- Division of Biological Sciences and University of California Cancer Center, University of California La Jolla, CA 92093
| | - Wei Zhu
- Division of Biological Sciences and University of California Cancer Center, University of California La Jolla, CA 92093
| | | | | | | | - Michael David
- Division of Biological Sciences and University of California Cancer Center, University of California La Jolla, CA 92093
- Address correspondence and reprint requests to Dr. Michael David, University of California Department of Biology, Bonner Hall 3138, 9500 Gilman Drive, La Jolla, CA 92093-0322.
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