1
|
Liu X, Shi X, Zhao H, Wang C. Exploring the molecular mechanisms of comorbidity of myocardial infarction and anxiety disorders by combining multiple data sets with in vivo experimental validation. Int Immunopharmacol 2025; 146:113852. [PMID: 39733641 DOI: 10.1016/j.intimp.2024.113852] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2024] [Revised: 11/25/2024] [Accepted: 12/10/2024] [Indexed: 12/31/2024]
Abstract
BACKGROUND The incidence of comorbidity between myocardial infarction (MI) and anxiety disorders is increasing. However, the biological association between them has not been fully understood. OBJECTIVE This study aims to investigate the molecular mechanisms of comorbidity between MI and anxiety disorders and to predict their key genes and potential therapeutic drugs. METHODS We searched Gene Expression Omnibus databases and performed differential analyses using the limma package to identify the functional enrichment of differential genes. Next, we constructed regulatory networks to investigate the relationship between hub genes and autophagy, ferroptosis, and immunity. Furthermore, we predicted transcription factors by R package, constructed a miRNA network, performed the single-cell analysis of key gene expression, and predicted drug targeting of differential genes using the Connectivity Map database. RESULTS The datasets for MI and anxiety disorders were analyzed for up and down-regulated differential genes, resulting in 35 intersecting differential genes. The top 10 feature genes from each dataset were intersected using Random Forest, resulting in the identification of three intersecting genes: STK17B, AKIRIN2, and WDR77. Validation of the above key genes was carried out by in vitro experiments. We examined the gene expression of STK17B, WDR77 and AKIRIN2 in the hippocampus and myocardial infarction border zone respectively by qPCR and WB, and the results confirmed that the above are the key genes for myocardial infarction and anxiety. There is a significant correlation between the comorbidity mechanism of myocardial infarction and anxiety disorders with ferroptosis and immunity. The construction of the miRNA network revealed that miR-205 and let-7 had higher average connectivity among the three hub genes. The single-cell analysis revealed significant expression of key genes in Endothelial cells, Cardiomyocytes, Macrophages, and Fibroblasts datasets. Cd274 showed a higher correlation with key genes in myocardial infarction and anxiety disorders. CONCLUSION Validation by multiple datasets and in vitro experiments showed that STK17B, AKIRIN2, and WDR77 are the key genes in the comorbidity of myocardial infarction and anxiety disorders, and ferroptosis and immunity are the key links in the comorbidity mechanism of myocardial infarction and anxiety disorders.
Collapse
Affiliation(s)
- Xiang Liu
- Beijing University of Chinese Medicine, Beijing, China.
| | - Xiaojun Shi
- Beijing University of Chinese Medicine, Beijing, China
| | - Haibin Zhao
- Dongfang Hospital of Beijing University of Chinese Medicine, Beijing, China
| | - Chao Wang
- Dongfang Hospital of Beijing University of Chinese Medicine, Beijing, China.
| |
Collapse
|
2
|
Wilander BA, Harris TL, Mandarano AH, Guy CS, Prater MS, Pruett-Miller SM, Ogden SK, McGargill MA. DRAK2 regulates myosin light chain phosphorylation in T cells. J Cell Sci 2024; 137:jcs261813. [PMID: 39421891 DOI: 10.1242/jcs.261813] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2023] [Accepted: 10/09/2024] [Indexed: 10/19/2024] Open
Abstract
Death-associated protein kinase-related apoptosis-inducing kinase-2 (DRAK2; also known as STK17B) is a serine/threonine kinase expressed in T cells. Drak2-deficient (Drak2-/-) mice respond effectively to tumors and pathogens while displaying resistance to T cell-mediated autoimmune disease. However, the molecular mechanisms by which DRAK2 impacts T cell function remain unclear. Gaining further insight into the function of DRAK2 in T cells will shed light on differentially regulated pathways in autoreactive and pathogen-specific T cells, which is crucial for improving autoimmune therapies. Here, we demonstrate that DRAK2 contributes to activation of myosin light chain (MLC2, encoded by Myl2) in both murine and human T cells. In the absence of Drak2, the amount of polymerized actin was decreased, suggesting that DRAK2 modulates actomyosin dynamics. We further show that myosin-dependent T cell functions, such as migration, T cell receptor microcluster accumulation, and conjugation to antigen presenting cells are decreased in the absence of Drak2. These findings reveal that DRAK2 plays an important role in regulating MLC activation within T cells.
Collapse
Affiliation(s)
- Benjamin A Wilander
- Department of Immunology, St. Jude Children's Research Hospital, Memphis, TN 38105, USA
- Graduate School of Biomedical Sciences, St. Jude Children's Research Hospital, Memphis, TN 38105, USA
| | - Tarsha L Harris
- Department of Immunology, St. Jude Children's Research Hospital, Memphis, TN 38105, USA
| | - Alexandra H Mandarano
- Department of Immunology, St. Jude Children's Research Hospital, Memphis, TN 38105, USA
| | - Cliff S Guy
- Department of Immunology, St. Jude Children's Research Hospital, Memphis, TN 38105, USA
| | - Mollie S Prater
- The Center for Advanced Genome Engineering, St. Jude Children's Research Hospital, Memphis, TN 38105, USA
- Department of Cell and Molecular Biology, St. Jude Children's Research Hospital, Memphis, TN 38105, USA
| | - Shondra M Pruett-Miller
- The Center for Advanced Genome Engineering, St. Jude Children's Research Hospital, Memphis, TN 38105, USA
- Department of Cell and Molecular Biology, St. Jude Children's Research Hospital, Memphis, TN 38105, USA
| | - Stacey K Ogden
- Department of Cell and Molecular Biology, St. Jude Children's Research Hospital, Memphis, TN 38105, USA
| | - Maureen A McGargill
- Department of Immunology, St. Jude Children's Research Hospital, Memphis, TN 38105, USA
| |
Collapse
|
3
|
Scheuplein F, Renner F, Campbell JE, Campbell R, De Savi C, Eckmann J, Fischer H, Ge J, Green L, Jakob P, Kim JL, Kinkema C, McGinn K, Medina R, Müller A, Perez N, Perola E, Timsit Y, Traore T, Hopfer U, Tyanova S, Tzouros M, Wang R, Woessner R, Dorsch M, Bischoff JR. Evaluation of STK17B as a cancer immunotherapy target utilizing highly potent and selective small molecule inhibitors. Front Immunol 2024; 15:1411395. [PMID: 39502695 PMCID: PMC11536310 DOI: 10.3389/fimmu.2024.1411395] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2024] [Accepted: 09/20/2024] [Indexed: 11/08/2024] Open
Abstract
Introduction The serine/threonine kinase 17B (STK17B) is involved in setting the threshold for T cell activation and its absence sensitizes T cells to suboptimal stimuli. Consequently, STK17B represents an attractive potential target for cancer immunotherapy. Methods To assess the potential of STK17B as an immuno-oncology target, we developed potent and selective tool compounds from starting points in Blueprint Medicines Corporation's proprietary kinase inhibitor library. To characterize these molecules, enzyme and cellular assays for STK17A and STK17B were established to drive chemistry optimization. Mass spectrometry-based phosphoproteomics profiling with tool inhibitors led to the identification of Ser19 on myosin light chain 2 as STK17B substrate, which is then developed into a flow cytometry-based pharmacodynamic readout of STK17B inhibition both in vitro and in vivo. Results In a mouse T cell activation assay, STK17B inhibitors demonstrated the ability to enhance interleukin-2 (IL-2) production. Similarly, treatment with STK17B inhibitors resulted in stronger cytokine secretion in human T cells activated using a T cell bispecific antibody. Subsequent chemistry optimization led to the identification of a highly selective and orally bioavailable tool compound, BLU7482. In vivo, STK17B inhibition led to dose-dependent modulation of myosin light chain 2 phosphorylation and enhanced priming of naïve T cells, as determined by upregulation of CD69, IL-2 and interferon-γ secretion. In line with increased T cell activation, treatment with STK17B inhibitor enhanced antitumor activity of anti-PD-L1 antibody in the MCA205 model. Conclusions In summary, we successfully identified and optimized STK17B kinase inhibitors which led to increased T cell responses in vitro and in vivo. This allowed us to evaluate the potential of STK17B inhibition as an approach for cancer immunotherapy.
Collapse
Affiliation(s)
| | | | | | - Robert Campbell
- Blueprint Medicines Corporation, Cambridge, MA, United States
| | - Chris De Savi
- Blueprint Medicines Corporation, Cambridge, MA, United States
| | - Jan Eckmann
- Roche Innovation Center Munich, Penzberg, Germany
| | | | - Jie Ge
- Blueprint Medicines Corporation, Cambridge, MA, United States
| | - Luke Green
- Roche Innovation Center Basel, Basel, Switzerland
| | - Peter Jakob
- Roche Innovation Center Basel, Basel, Switzerland
| | - Joseph L. Kim
- Blueprint Medicines Corporation, Cambridge, MA, United States
| | - Caitlin Kinkema
- Blueprint Medicines Corporation, Cambridge, MA, United States
| | - Katie McGinn
- Blueprint Medicines Corporation, Cambridge, MA, United States
| | - Ricardo Medina
- Blueprint Medicines Corporation, Cambridge, MA, United States
| | | | - Nisha Perez
- Blueprint Medicines Corporation, Cambridge, MA, United States
| | - Emanuele Perola
- Blueprint Medicines Corporation, Cambridge, MA, United States
| | - Yoav Timsit
- Blueprint Medicines Corporation, Cambridge, MA, United States
| | - Tary Traore
- Blueprint Medicines Corporation, Cambridge, MA, United States
| | | | | | | | - Ruduan Wang
- Blueprint Medicines Corporation, Cambridge, MA, United States
| | | | - Marion Dorsch
- Blueprint Medicines Corporation, Cambridge, MA, United States
| | | |
Collapse
|
4
|
Laletin V, Bernard PL, Costa da Silva C, Guittard G, Nunes JA. Negative intracellular regulators of T-cell receptor (TCR) signaling as potential antitumor immunotherapy targets. J Immunother Cancer 2023; 11:e005845. [PMID: 37217244 PMCID: PMC10231026 DOI: 10.1136/jitc-2022-005845] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/21/2023] [Indexed: 05/24/2023] Open
Abstract
Immunotherapy strategies aim to mobilize immune defenses against tumor cells by targeting mainly T cells. Co-inhibitory receptors or immune checkpoints (ICPs) (such as PD-1 and CTLA4) can limit T cell receptor (TCR) signal propagation in T cells. Antibody-based blocking of immune checkpoints (immune checkpoint inhibitors, ICIs) enable escape from ICP inhibition of TCR signaling. ICI therapies have significantly impacted the prognosis and survival of patients with cancer. However, many patients remain refractory to these treatments. Thus, alternative approaches for cancer immunotherapy are needed. In addition to membrane-associated inhibitory molecules, a growing number of intracellular molecules may also serve to downregulate signaling cascades triggered by TCR engagement. These molecules are known as intracellular immune checkpoints (iICPs). Blocking the expression or the activity of these intracellular negative signaling molecules is a novel field of action to boost T cell-mediated antitumor responses. This area is rapidly expanding. Indeed, more than 30 different potential iICPs have been identified. Over the past 5 years, several phase I/II clinical trials targeting iICPs in T cells have been registered. In this study, we summarize recent preclinical and clinical data demonstrating that immunotherapies targeting T cell iICPs can mediate regression of solid tumors including (membrane associated) immune-checkpoint inhibitor refractory cancers. Finally, we discuss how these iICPs are targeted and controlled. Thereby, iICP inhibition is a promising strategy opening new avenues for future cancer immunotherapy treatments.
Collapse
Affiliation(s)
- Vladimir Laletin
- Immunity and Cancer, Cancer Research Centre Marseille, Marseille, France
- Onco-hematology and immuno-oncology (OHIO), Centre de Recherche en Cancérologie de Marseille, Marseille, France
| | - Pierre-Louis Bernard
- Immunity and Cancer, Cancer Research Centre Marseille, Marseille, France
- Onco-hematology and immuno-oncology (OHIO), Centre de Recherche en Cancérologie de Marseille, Marseille, France
| | - Cathy Costa da Silva
- Immunity and Cancer, Cancer Research Centre Marseille, Marseille, France
- Onco-hematology and immuno-oncology (OHIO), Centre de Recherche en Cancérologie de Marseille, Marseille, France
| | - Geoffrey Guittard
- Immunity and Cancer, Cancer Research Centre Marseille, Marseille, France
- Onco-hematology and immuno-oncology (OHIO), Centre de Recherche en Cancérologie de Marseille, Marseille, France
| | - Jacques A Nunes
- Immunity and Cancer, Cancer Research Centre Marseille, Marseille, France
- Onco-hematology and immuno-oncology (OHIO), Centre de Recherche en Cancérologie de Marseille, Marseille, France
| |
Collapse
|
5
|
Mandarano AH, Harris TL, Creasy BM, Wehenkel M, Duggar M, Wilander BA, Mishra A, Crawford JC, Mullen SA, Williams KM, Pillai M, High AA, McGargill MA. DRAK2 contributes to type 1 diabetes by negatively regulating IL-2 sensitivity to alter regulatory T cell development. Cell Rep 2023; 42:112106. [PMID: 36773294 PMCID: PMC10412737 DOI: 10.1016/j.celrep.2023.112106] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2021] [Revised: 11/02/2022] [Accepted: 01/27/2023] [Indexed: 02/12/2023] Open
Abstract
Drak2-deficient (Drak2-/-) mice are resistant to multiple models of autoimmunity yet effectively eliminate pathogens and tumors. Thus, DRAK2 represents a potential target to treat autoimmune diseases. However, the mechanisms by which DRAK2 contributes to autoimmunity, particularly type 1 diabetes (T1D), remain unresolved. Here, we demonstrate that resistance to T1D in non-obese diabetic (NOD) mice is due to the absence of Drak2 in T cells and requires the presence of regulatory T cells (Tregs). Contrary to previous hypotheses, we show that DRAK2 does not limit TCR signaling. Rather, DRAK2 regulates IL-2 signaling by inhibiting STAT5A phosphorylation. We further demonstrate that enhanced sensitivity to IL-2 in the absence of Drak2 augments thymic Treg development. Overall, our data indicate that DRAK2 contributes to autoimmunity in multiple ways by regulating thymic Treg development and by impacting the sensitivity of conventional T cells to Treg-mediated suppression.
Collapse
Affiliation(s)
- Alexandra H Mandarano
- Department of Immunology, St. Jude Children's Research Hospital, Memphis, TN 38105, USA
| | - Tarsha L Harris
- Department of Immunology, St. Jude Children's Research Hospital, Memphis, TN 38105, USA
| | - Blaine M Creasy
- Department of Immunology, St. Jude Children's Research Hospital, Memphis, TN 38105, USA
| | - Marie Wehenkel
- Department of Immunology, St. Jude Children's Research Hospital, Memphis, TN 38105, USA
| | - Marygrace Duggar
- Department of Immunology, St. Jude Children's Research Hospital, Memphis, TN 38105, USA; St. Jude Graduate School of Biomedical Sciences, Memphis, TN 38105, USA
| | - Benjamin A Wilander
- Department of Immunology, St. Jude Children's Research Hospital, Memphis, TN 38105, USA; St. Jude Graduate School of Biomedical Sciences, Memphis, TN 38105, USA
| | - Ashutosh Mishra
- Center for Proteomics and Metabolomics, St. Jude Children's Research Hospital, Memphis, TN 38105, USA
| | - Jeremy Chase Crawford
- Department of Immunology, St. Jude Children's Research Hospital, Memphis, TN 38105, USA
| | - Sarah A Mullen
- Department of Immunology, St. Jude Children's Research Hospital, Memphis, TN 38105, USA
| | - Katherine M Williams
- Department of Immunology, St. Jude Children's Research Hospital, Memphis, TN 38105, USA
| | - Meenu Pillai
- Department of Immunology, St. Jude Children's Research Hospital, Memphis, TN 38105, USA
| | - Anthony A High
- Center for Proteomics and Metabolomics, St. Jude Children's Research Hospital, Memphis, TN 38105, USA
| | - Maureen A McGargill
- Department of Immunology, St. Jude Children's Research Hospital, Memphis, TN 38105, USA.
| |
Collapse
|
6
|
Park S, Kye S, Jung ME, Chae CH, Yang K, Kim S, Choi G, Lee K. Discovery of TRD‐93 as a novel
DRAK2
inhibitor. B KOREAN CHEM SOC 2023. [DOI: 10.1002/bkcs.12680] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Affiliation(s)
- Sangjun Park
- Bio & Drug Discovery Division Korea Research Institute of Chemical Technology Daejeon South Korea
- Medicinal Chemistry & Pharmacology University of Science & Technology Daejeon South Korea
| | - Seungmin Kye
- Bio & Drug Discovery Division Korea Research Institute of Chemical Technology Daejeon South Korea
- Medicinal Chemistry & Pharmacology University of Science & Technology Daejeon South Korea
| | - Myoung Eun Jung
- Bio & Drug Discovery Division Korea Research Institute of Chemical Technology Daejeon South Korea
| | - Chong Hak Chae
- Bio & Drug Discovery Division Korea Research Institute of Chemical Technology Daejeon South Korea
| | | | | | - Gildon Choi
- Bio & Drug Discovery Division Korea Research Institute of Chemical Technology Daejeon South Korea
- Medicinal Chemistry & Pharmacology University of Science & Technology Daejeon South Korea
| | - Kwangho Lee
- Bio & Drug Discovery Division Korea Research Institute of Chemical Technology Daejeon South Korea
- Medicinal Chemistry & Pharmacology University of Science & Technology Daejeon South Korea
| |
Collapse
|
7
|
Qian XQ, Xu GB, Liu LY, Yang T, Zhang GL, Li GY. Chaetonigrisins A–L, a group of 3-Indole-1,2-Propanediol derived alkaloids from Chaetomium nigricolor YT-2. Bioorg Chem 2023; 130:106201. [DOI: 10.1016/j.bioorg.2022.106201] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2022] [Revised: 09/20/2022] [Accepted: 10/06/2022] [Indexed: 11/06/2022]
|
8
|
Ferjancic Z, Kukuruzar A, Bihelovic F. Total Synthesis of (+)‐Alstonlarsine A. Angew Chem Int Ed Engl 2022; 61:e202210297. [DOI: 10.1002/anie.202210297] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2022] [Indexed: 12/31/2022]
Affiliation(s)
- Zorana Ferjancic
- University of Belgrade— Faculty of Chemistry Studentski trg 16, POB 51 11158 Belgrade 118 Serbia
| | - Andrej Kukuruzar
- University of Belgrade— Faculty of Chemistry Studentski trg 16, POB 51 11158 Belgrade 118 Serbia
| | - Filip Bihelovic
- University of Belgrade— Faculty of Chemistry Studentski trg 16, POB 51 11158 Belgrade 118 Serbia
| |
Collapse
|
9
|
Wu QW, Kapfhammer JP. The Emerging Key Role of the mGluR1-PKCγ Signaling Pathway in the Pathogenesis of Spinocerebellar Ataxias: A Neurodevelopmental Viewpoint. Int J Mol Sci 2022; 23:ijms23169169. [PMID: 36012439 PMCID: PMC9409119 DOI: 10.3390/ijms23169169] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2022] [Revised: 08/11/2022] [Accepted: 08/12/2022] [Indexed: 12/19/2022] Open
Abstract
Spinocerebellar ataxias (SCAs) are a heterogeneous group of autosomal dominantly inherited progressive disorders with degeneration and dysfunction of the cerebellum. Although different subtypes of SCAs are classified according to the disease-associated causative genes, the clinical syndrome of the ataxia is shared, pointing towards a possible convergent pathogenic pathway among SCAs. In this review, we summarize the role of SCA-associated gene function during cerebellar Purkinje cell development and discuss the relationship between SCA pathogenesis and neurodevelopment. We will summarize recent studies on molecules involved in SCA pathogenesis and will focus on the mGluR1-PKCγ signaling pathway evaluating the possibility that this might be a common pathway which contributes to these diseases.
Collapse
|
10
|
Ferjancic Z, Kukuruzar A, Bihelovic F. Total Synthesis of (+)‐Alstonlarsine A. Angew Chem Int Ed Engl 2022. [DOI: 10.1002/ange.202210297] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Affiliation(s)
- Zorana Ferjancic
- Univerzitet u Beogradu Hemijski fakultet Faculty of Chemistry 11158 Belgrade SERBIA
| | - Andrej Kukuruzar
- Univerzitet u Beogradu Hemijski fakultet Faculty of Chemistry 11158 Belgrade SERBIA
| | - Filip Bihelovic
- University of Belgrade Faculty of Chemistry Studentski trg 12-16 11158 Belgrade SERBIA
| |
Collapse
|
11
|
Shi X, Zhou Q, Huang B, Xia S, Jiang Y, Fang S, Lin J. Prognostic and immune-related value of STK17B in skin cutaneous melanoma. PLoS One 2022; 17:e0263311. [PMID: 35171924 PMCID: PMC8849620 DOI: 10.1371/journal.pone.0263311] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2021] [Accepted: 01/16/2022] [Indexed: 11/26/2022] Open
Abstract
Skin cutaneous melanoma (SKCM) is a common cancer of which mortality is increasing continuously. Our study conducted a series of analyses on the clinical significance of Serine/threonine kinase 17B (STK17B) in SKCM to provide a new biomarker for diagnosis and treatment. The RNA-sequence data were obtained from The Cancer Genome Atlas and Genotype-Tissue Expression databases. The data of 468 SKCM patients were divided into STK17B high- and low-expression groups and analyzed by Bioconductor package to identify the differential expressed genes. The R package of "clusterProfiler" was used for Gene Ontology, Kyoto Encyclopedia of Genes and Genomes, and Gene-Set Enrichment Analysis analyses. A protein-protein interaction network and immune infiltration landscape were respectively constructed via STRING database and ssGSEA. STK17B had lower expression in SKCM than normal tissues. Besides, STK17B expression was significantly related to some clinicopathological characteristics in SKCM patients including T stage, Breslow depth, radiation therapy, melanoma Clark level, and pathologic stage. The Kaplan-Meier curve analyses revealed that the low expression of STK17B was correlated with poor overall survival and disease-specific survival. We constructed nomograms to predict the 1-, 3-, and 5-year survival of SKCM patients. The function enrichment analyses showed STK17B-related differential expressed genes were enriched in cellular differentiation and immune-related progress. STK17B expression level were positively correlated with infiltrating level of immune cells. In this study, we found that STK17B, which played an important role in immune infiltration, could be a new biomarker for diagnosis and prognosis in SKCM patients.
Collapse
Affiliation(s)
- Xueying Shi
- Clinical Laboratory of Integrative Medicine, The First Affiliated Hospital of Dalian Medical University, Dalian, Liaoning, China
- Institute (College) of Integrative Medicine, Dalian Medical University, Dalian, Liaoning, China
| | - Qi Zhou
- Clinical Laboratory of Integrative Medicine, The First Affiliated Hospital of Dalian Medical University, Dalian, Liaoning, China
- Institute (College) of Integrative Medicine, Dalian Medical University, Dalian, Liaoning, China
| | - Bingqian Huang
- Clinical Laboratory of Integrative Medicine, The First Affiliated Hospital of Dalian Medical University, Dalian, Liaoning, China
- Institute (College) of Integrative Medicine, Dalian Medical University, Dalian, Liaoning, China
| | - Shilin Xia
- Clinical Laboratory of Integrative Medicine, The First Affiliated Hospital of Dalian Medical University, Dalian, Liaoning, China
| | - Yuankuan Jiang
- Department of Dermatology, The First Affiliated Hospital of Dalian Medical University, Dalian, Liaoning, China
| | - Shifeng Fang
- Department of Ophthalmology, The First Affiliated Hospital of Dalian Medical University, Dalian, Liaoning, China
| | - Jingrong Lin
- Department of Dermatology, The First Affiliated Hospital of Dalian Medical University, Dalian, Liaoning, China
| |
Collapse
|
12
|
Li Y, Xu J, Lu Y, Bian H, Yang L, Wu H, Zhang X, Zhang B, Xiong M, Chang Y, Tang J, Yang F, Zhao L, Li J, Gao X, Xia M, Tan M, Li J. DRAK2 aggravates nonalcoholic fatty liver disease progression through SRSF6-associated RNA alternative splicing. Cell Metab 2021; 33:2004-2020.e9. [PMID: 34614409 DOI: 10.1016/j.cmet.2021.09.008] [Citation(s) in RCA: 56] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/10/2021] [Revised: 07/26/2021] [Accepted: 09/13/2021] [Indexed: 02/06/2023]
Abstract
Nonalcoholic steatohepatitis (NASH) is an advanced stage of nonalcoholic fatty liver disease (NAFLD) with serious consequences that currently lacks approved pharmacological therapies. Recent studies suggest the close relationship between the pathogenesis of NAFLD and the dysregulation of RNA splicing machinery. Here, we reveal death-associated protein kinase-related apoptosis-inducing kinase-2 (DRAK2) is markedly upregulated in the livers of both NAFLD/NASH patients and NAFLD/NASH diet-fed mice. Hepatic deletion of DRAK2 suppresses the progression of hepatic steatosis to NASH. Comprehensive analyses of the phosphoproteome and transcriptome indicated a crucial role of DRAK2 in RNA splicing and identified the splicing factor SRSF6 as a direct binding protein of DRAK2. Further studies demonstrated that binding to DRAK2 inhibits SRSF6 phosphorylation by the SRSF kinase SRPK1 and regulates alternative splicing of mitochondrial function-related genes. In conclusion, our findings reveal an indispensable role of DRAK2 in NAFLD/NASH and offer a potential therapeutic target for this disease.
Collapse
Affiliation(s)
- Yufeng Li
- State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai 201203, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Junyu Xu
- State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai 201203, China
| | - Yuting Lu
- State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai 201203, China
| | - Hua Bian
- Department of Endocrinology and Metabolism, Zhongshan Hospital, Fudan University, Shanghai 200032, China; Fudan Institute for Metabolic Diseases, Shanghai 200032, China
| | - Lin Yang
- State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai 201203, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Honghong Wu
- State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai 201203, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Xinwen Zhang
- State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai 201203, China
| | - Beilei Zhang
- State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai 201203, China
| | - Maoqian Xiong
- Shanghai Engineering Research Center of Molecular Therapeutics and New Drug Development, School of Chemistry and Molecular Engineering, East China Normal University, Shanghai 200062, China
| | - Yafei Chang
- Department of Bioinformatics and Biostatistics, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Jie Tang
- Shanghai Engineering Research Center of Molecular Therapeutics and New Drug Development, School of Chemistry and Molecular Engineering, East China Normal University, Shanghai 200062, China
| | - Fan Yang
- Shanghai Engineering Research Center of Molecular Therapeutics and New Drug Development, School of Chemistry and Molecular Engineering, East China Normal University, Shanghai 200062, China
| | - Lei Zhao
- State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai 201203, China
| | - Jing Li
- Department of Bioinformatics and Biostatistics, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Xin Gao
- Department of Endocrinology and Metabolism, Zhongshan Hospital, Fudan University, Shanghai 200032, China; Fudan Institute for Metabolic Diseases, Shanghai 200032, China
| | - Mingfeng Xia
- Department of Endocrinology and Metabolism, Zhongshan Hospital, Fudan University, Shanghai 200032, China; Fudan Institute for Metabolic Diseases, Shanghai 200032, China.
| | - Minjia Tan
- State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai 201203, China; University of Chinese Academy of Sciences, Beijing 100049, China.
| | - Jingya Li
- State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai 201203, China; University of Chinese Academy of Sciences, Beijing 100049, China; School of Pharmaceutical Science and Technology, Hangzhou Institute for Advanced Study, University of Chinese Academy of Sciences, Hangzhou 310024, China.
| |
Collapse
|
13
|
Picado A, Chaikuad A, Wells CI, Shrestha S, Zuercher WJ, Pickett JE, Kwarcinski FE, Sinha P, de Silva CS, Zutshi R, Liu S, Kannan N, Knapp S, Drewry DH, Willson TM. A Chemical Probe for Dark Kinase STK17B Derives Its Potency and High Selectivity through a Unique P-Loop Conformation. J Med Chem 2020; 63:14626-14646. [PMID: 33215924 PMCID: PMC7816213 DOI: 10.1021/acs.jmedchem.0c01174] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
STK17B is a member of the death-associated protein kinase family and has been genetically linked to the development of diverse diseases. However, the role of STK17B in normal and disease pathology is poorly defined. Here, we present the discovery of thieno[3,2-d] pyrimidine SGC-STK17B-1 (11s), a high-quality chemical probe for this understudied "dark" kinase. 11s is an ATP-competitive inhibitor that showed remarkable selectivity over other kinases including the closely related STK17A. X-ray crystallography of 11s and related thieno[3,2-d]pyrimidines bound to STK17B revealed a unique P-loop conformation characterized by a salt bridge between R41 and the carboxylic acid of the inhibitor. Molecular dynamic simulations of STK17B revealed the flexibility of the P-loop and a wide range of R41 conformations available to the apo-protein. The isomeric thieno[2,3-d]pyrimidine SGC-STK17B-1N (19g) was identified as a negative control compound. The >100-fold lower activity of 19g on STK17B was attributed to the reduced basicity of its pyrimidine N1.
Collapse
Affiliation(s)
- Alfredo Picado
- Structural Genomics Consortium, UNC Eshelman School of Pharmacy, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, 27599-7264
| | - Apirat Chaikuad
- Institute of Pharmaceutical Chemistry, Max-von-Laue-Straße 9, Goethe University Frankfurt, 60438 Frankfurt, Germany
- Structural Genomics Consortium, Buchmann Institute for Molecular Life Sciences (BMLS), Max-von-Laue-Straße 15, 60438 Frankfurt, Germany
| | - Carrow I. Wells
- Structural Genomics Consortium, UNC Eshelman School of Pharmacy, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, 27599-7264
| | - Safal Shrestha
- Institute of Bioinformatics, University of Georgia, Athens, GA 30602, USA
| | - William J. Zuercher
- Structural Genomics Consortium, UNC Eshelman School of Pharmacy, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, 27599-7264
| | - Julie E. Pickett
- Structural Genomics Consortium, UNC Eshelman School of Pharmacy, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, 27599-7264
| | | | - Parvathi Sinha
- Luceome Biotechnologies, 1665 E. 18th Street, Suite 106, Tucson, AZ 85719
| | - Chandi S. de Silva
- Luceome Biotechnologies, 1665 E. 18th Street, Suite 106, Tucson, AZ 85719
| | - Reena Zutshi
- Luceome Biotechnologies, 1665 E. 18th Street, Suite 106, Tucson, AZ 85719
| | - Shubin Liu
- Research Computing Center, University of North Carolina, Chapel Hill, NC 27599-3420
| | - Natarajan Kannan
- Institute of Bioinformatics, University of Georgia, Athens, GA 30602, USA
- Department of Biochemistry and Molecular Biology, University of Georgia, Athens, GA 30602
| | - Stefan Knapp
- Institute of Pharmaceutical Chemistry, Max-von-Laue-Straße 9, Goethe University Frankfurt, 60438 Frankfurt, Germany
- Structural Genomics Consortium, Buchmann Institute for Molecular Life Sciences (BMLS), Max-von-Laue-Straße 15, 60438 Frankfurt, Germany
- German Translational Cancer Network (DKTK) site Frankfurt/Mainz
- Frankfurt Cancer Institute (FCI), Paul-Ehrlich-Straße 42-44, 60596 Frankfurt am Main
| | - David H. Drewry
- Structural Genomics Consortium, UNC Eshelman School of Pharmacy, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, 27599-7264
| | - Timothy M. Willson
- Structural Genomics Consortium, UNC Eshelman School of Pharmacy, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, 27599-7264
| |
Collapse
|
14
|
Szoltysek K, Ciardullo C, Zhou P, Walaszczyk A, Willmore E, Rand V, Marshall S, Hall A, J. Harrison C, Eswaran J, Soundararajan M. DAP Kinase-Related Apoptosis-Inducing Protein Kinase 2 (DRAK2) Is a Key Regulator and Molecular Marker in Chronic Lymphocytic Leukemia. Int J Mol Sci 2020; 21:ijms21207663. [PMID: 33081245 PMCID: PMC7593912 DOI: 10.3390/ijms21207663] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2020] [Revised: 10/13/2020] [Accepted: 10/14/2020] [Indexed: 02/07/2023] Open
Abstract
Chronic lymphocytic leukemia (CLL) is the most common adult leukemia in the Western World and it is characterized by a marked degree of clinical heterogeneity. An impaired balance between pro- and anti-apoptotic stimuli determines chemorefractoriness and outcome. The low proliferation rate of CLL cells indicates that one of the primary mechanisms involved in disease development may be an apoptotic failure. Here, we study the clinical and functional significance of DRAK2, a novel stress response kinase that plays a critical role in apoptosis, T-cell biology, and B-cell activation in CLL. We have analyzed CLL patient samples and showed that low expression levels of DRAK2 were significantly associated with unfavorable outcome in our CLL cohort. DRAK2 expression levels showed a positive correlation with the expression of DAPK1, and TGFBR1. Consistent with clinical data, the downregulation of DRAK2 in MEC-1 CLL cells strongly increased cell viability and proliferation. Further, our transcriptome data from MEC-1 cells highlighted MAPK, NF-κB, and Akt and as critical signaling hubs upon DRAK2 knockdown. Taken together, our results indicate DRAK2 as a novel marker of CLL survival that plays key regulatory roles in CLL prognosis.
Collapse
MESH Headings
- Aged
- Apoptosis Regulatory Proteins/genetics
- Apoptosis Regulatory Proteins/metabolism
- Biomarkers, Tumor/genetics
- Biomarkers, Tumor/metabolism
- Cell Proliferation
- Cell Survival
- Death-Associated Protein Kinases/genetics
- Death-Associated Protein Kinases/metabolism
- Down-Regulation
- Female
- Humans
- Leukemia, Lymphocytic, Chronic, B-Cell/metabolism
- Leukemia, Lymphocytic, Chronic, B-Cell/pathology
- MAP Kinase Signaling System
- Male
- Middle Aged
- NF-kappa B/genetics
- NF-kappa B/metabolism
- Protein Serine-Threonine Kinases/genetics
- Protein Serine-Threonine Kinases/metabolism
- Proto-Oncogene Proteins c-akt/genetics
- Proto-Oncogene Proteins c-akt/metabolism
- Receptor, Transforming Growth Factor-beta Type I/genetics
- Receptor, Transforming Growth Factor-beta Type I/metabolism
Collapse
Affiliation(s)
- Katarzyna Szoltysek
- Translational and Clinical Research Institute, Newcastle University, Newcastle upon Tyne NE1 7RU, UK; (K.S.); (C.C.); (E.W.); (A.H.); (C.J.H.)
- Maria Skłodowska-Curie Institute, Oncology Center, Gliwice Branch, 02-034 Gliwice, Poland
| | - Carmela Ciardullo
- Translational and Clinical Research Institute, Newcastle University, Newcastle upon Tyne NE1 7RU, UK; (K.S.); (C.C.); (E.W.); (A.H.); (C.J.H.)
- Department of Applied Sciences, Faculty of Health and Life Sciences, Northumbria University, Newcastle upon Tyne NE1 8ST, UK
| | - Peixun Zhou
- School of Health & Life Sciences, Teesside University, Middlesbrough TS1 3JN, UK; (P.Z.); (V.R.)
- National Horizons Centre, Teesside University, Darlington DL1 1HG, UK
| | - Anna Walaszczyk
- Institute of Biosciences, International Centre for Life, Newcastle University, Newcastle upon Tyne NE1 7RU, UK;
| | - Elaine Willmore
- Translational and Clinical Research Institute, Newcastle University, Newcastle upon Tyne NE1 7RU, UK; (K.S.); (C.C.); (E.W.); (A.H.); (C.J.H.)
| | - Vikki Rand
- School of Health & Life Sciences, Teesside University, Middlesbrough TS1 3JN, UK; (P.Z.); (V.R.)
- National Horizons Centre, Teesside University, Darlington DL1 1HG, UK
| | - Scott Marshall
- Department of Haematology, City Hospitals Sunderland NHS Trust, Sunderland SR4 7TP, UK;
| | - Andy Hall
- Translational and Clinical Research Institute, Newcastle University, Newcastle upon Tyne NE1 7RU, UK; (K.S.); (C.C.); (E.W.); (A.H.); (C.J.H.)
| | - Christine J. Harrison
- Translational and Clinical Research Institute, Newcastle University, Newcastle upon Tyne NE1 7RU, UK; (K.S.); (C.C.); (E.W.); (A.H.); (C.J.H.)
| | - Jeyanthy Eswaran
- Translational and Clinical Research Institute, Newcastle University, Newcastle upon Tyne NE1 7RU, UK; (K.S.); (C.C.); (E.W.); (A.H.); (C.J.H.)
- Newcastle University Medicine Malaysia (NUMed Malaysia), EduCity, Iskandar 79200, Johor, Malaysia
- Correspondence: or (J.E); (M.S.)
| | - Meera Soundararajan
- Department of Applied Sciences, Faculty of Health and Life Sciences, Northumbria University, Newcastle upon Tyne NE1 8ST, UK
- Correspondence: or (J.E); (M.S.)
| |
Collapse
|
15
|
DAPK1 (death associated protein kinase 1) mediates mTORC1 activation and antiviral activities in CD8 + T cells. Cell Mol Immunol 2019; 18:138-149. [PMID: 31541182 DOI: 10.1038/s41423-019-0293-2] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2019] [Accepted: 08/27/2019] [Indexed: 12/18/2022] Open
Abstract
Mechanistic target of rapamycin complex 1 (mTORC1) regulates CD8+ T-cell differentiation and function. Despite the links between PI3K-AKT and mTORC1 activation in CD8+ T cells, the molecular mechanism underlying mTORC1 activation remains unclear. Here, we show that both the kinase activity and the death domain of DAPK1 are required for maximal mTOR activation and CD8+ T-cell function. We found that TCR-induced activation of calcineurin activates DAPK1, which subsequently interacts with TSC2 via its death domain and phosphorylates TSC2 to mediate mTORC1 activation. Furthermore, both the kinase domain and death domain of DAPK1 are required for CD8+ T-cell antiviral responses in an LCMV infection model. Together, our data reveal a novel mechanism of mTORC1 activation that mediates optimal CD8+ T-cell function and antiviral activity.
Collapse
|
16
|
Kerimi A, Williamson G. Differential Impact of Flavonoids on Redox Modulation, Bioenergetics, and Cell Signaling in Normal and Tumor Cells: A Comprehensive Review. Antioxid Redox Signal 2018; 29:1633-1659. [PMID: 28826224 PMCID: PMC6207159 DOI: 10.1089/ars.2017.7086] [Citation(s) in RCA: 36] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
SIGNIFICANCE Flavonoids can interact with multiple molecular targets to elicit their cellular effects, leading to changes in signal transduction, gene expression, and/or metabolism, which can, subsequently, affect the entire cell and organism. Immortalized cell lines, derived from tumors, are routinely employed as a surrogate for mechanistic studies, with the results extrapolated to tissues in vivo. Recent Advances: We review the activities of selected flavonoids on cultured tumor cells derived from various tissues in comparison to corresponding primary cells or tissues in vivo, mainly using quercetin and flavanols (epicatechin and (-)-epigallocatechin gallate) as exemplars. Several studies have indicated that flavonoids could retard cancer progression in vivo in animal models as well as in tumor cell models. CRITICAL ISSUES Extrapolation from in vitro and animal models to humans is not straightforward given both the extensive conjugation and complex microbiota-dependent metabolism of flavonoids after consumption, as well as the heterogeneous metabolism of different tumors. FUTURE DIRECTIONS Comparison of data from studies on primary cells or in vivo are essential not only to validate results obtained from cultured cell models, but also to highlight whether any differences may be further exploited in the clinical setting for chemoprevention. Tumor cell models can provide a useful mechanistic tool to study the effects of flavonoids, provided that the limitations of each model are understood and taken into account in interpretation of the data.
Collapse
Affiliation(s)
- Asimina Kerimi
- School of Food Science and Nutrition, University of Leeds , Leeds, United Kingdom
| | - Gary Williamson
- School of Food Science and Nutrition, University of Leeds , Leeds, United Kingdom
| |
Collapse
|
17
|
Elbadawy M, Usui T, Yamawaki H, Sasaki K. Novel Functions of Death-Associated Protein Kinases through Mitogen-Activated Protein Kinase-Related Signals. Int J Mol Sci 2018; 19:3031. [PMID: 30287790 PMCID: PMC6213522 DOI: 10.3390/ijms19103031] [Citation(s) in RCA: 37] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2018] [Revised: 10/01/2018] [Accepted: 10/01/2018] [Indexed: 01/05/2023] Open
Abstract
Death associated protein kinase (DAPK) is a calcium/calmodulin-regulated serine/threonine kinase; its main function is to regulate cell death. DAPK family proteins consist of DAPK1, DAPK2, DAPK3, DAPK-related apoptosis-inducing protein kinases (DRAK)-1 and DRAK-2. In this review, we discuss the roles and regulatory mechanisms of DAPK family members and their relevance to diseases. Furthermore, a special focus is given to several reports describing cross-talks between DAPKs and mitogen-activated protein kinases (MAPK) family members in various pathologies. We also discuss small molecule inhibitors of DAPKs and their potential as therapeutic targets against human diseases.
Collapse
Affiliation(s)
- Mohamed Elbadawy
- Laboratory of Veterinary Pharmacology, Department of Veterinary Medicine, Faculty of Agriculture, Tokyo University of Agriculture and Technology, 3-5-8 Saiwai-cho, Fuchu, Tokyo 183-8509, Japan.
- Department of Pharmacology, Faculty of Veterinary Medicine, Benha University, Moshtohor, Elqaliobiya, Toukh 13736, Egypt.
| | - Tatsuya Usui
- Laboratory of Veterinary Pharmacology, Department of Veterinary Medicine, Faculty of Agriculture, Tokyo University of Agriculture and Technology, 3-5-8 Saiwai-cho, Fuchu, Tokyo 183-8509, Japan.
| | - Hideyuki Yamawaki
- Laboratory of Veterinary Pharmacology, School of Veterinary Medicine, Kitasato University, Towada, Aomori 034-8628, Japan.
| | - Kazuaki Sasaki
- Laboratory of Veterinary Pharmacology, Department of Veterinary Medicine, Faculty of Agriculture, Tokyo University of Agriculture and Technology, 3-5-8 Saiwai-cho, Fuchu, Tokyo 183-8509, Japan.
| |
Collapse
|
18
|
Farag AK, Roh EJ. Death-associated protein kinase (DAPK) family modulators: Current and future therapeutic outcomes. Med Res Rev 2018; 39:349-385. [PMID: 29949198 DOI: 10.1002/med.21518] [Citation(s) in RCA: 56] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2018] [Revised: 05/06/2018] [Accepted: 06/03/2018] [Indexed: 12/22/2022]
Affiliation(s)
- Ahmed Karam Farag
- Chemical Kinomics Research Center; Korea Institute of Science and Technology (KIST); Seoul Republic of Korea
- Division of Bio-Medical Science &Technology, Korea Institute of Science and Technology (KIST) School; University of Science and Technology; Seoul Republic of Korea
| | - Eun Joo Roh
- Chemical Kinomics Research Center; Korea Institute of Science and Technology (KIST); Seoul Republic of Korea
- Division of Bio-Medical Science &Technology, Korea Institute of Science and Technology (KIST) School; University of Science and Technology; Seoul Republic of Korea
| |
Collapse
|
19
|
Investigation of indirubin derivatives: a combination of 3D-QSAR, molecular docking, and ADMET towards the design of new DRAK2 inhibitors. Struct Chem 2018. [DOI: 10.1007/s11224-018-1134-0] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
|
20
|
Lan Y, Han J, Wang Y, Wang J, Yang G, Li K, Song R, Zheng T, Liang Y, Pan S, Liu X, Zhu M, Liu Y, Meng F, Mohsin M, Cui Y, Zhang B, Subash S, Liu L. STK17B promotes carcinogenesis and metastasis via AKT/GSK-3β/Snail signaling in hepatocellular carcinoma. Cell Death Dis 2018; 9:236. [PMID: 29445189 PMCID: PMC5833726 DOI: 10.1038/s41419-018-0262-1] [Citation(s) in RCA: 47] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2017] [Revised: 11/10/2017] [Accepted: 11/24/2017] [Indexed: 12/24/2022]
Abstract
Hepatocellular carcinoma (HCC) is a lethal malignancy worldwide with frequent intrahepatic and distant metastasis. Elucidating the underlying molecular mechanism that modulates HCC progression is critical for exploring novel therapeutic strategies. Serine/Threonine Kinase 17B (STK17B) is upregulated in HCC tissues, but its role in HCC progression remains elusive. In the present studies, we reported that STK17B had a critical role in HCC progression. STK17B was significantly upregulated in HCC cell lines and specimens, and patients with ectopic STK17B expression characterized with poor clinicopathological features. In vitro and in vivo assay demonstrated that inhibition of STK17B markedly inhibits HCC tumorigenesis and metastasis, while STK17B overexpression promoted these processes. Furthermore, we found that STK17B promoted EMT process via activating AKT/GSK-3β/Snail signal pathway, and miR-455-3p was identified as the upstream regulator of STK17B. Combination of high level of STK17B and low level of miR-455-3p predicted poor prognosis with higher accuracy for HCC patients. In conclusion, our research demonstrated that STK17B promotes HCC progression, induces EMT process via activating AKT/GSK-3β/Snail signal and predicts poor prognosis in HCC.
Collapse
Affiliation(s)
- Yaliang Lan
- Department of Hepatic Surgery, The First Affiliated Hospital of Harbin Medical University, Key Laboratory of Hepatosplenic Surgery, Ministry of Education, Harbin, China
| | - Jihua Han
- Department of Hepatic Surgery, The First Affiliated Hospital of Harbin Medical University, Key Laboratory of Hepatosplenic Surgery, Ministry of Education, Harbin, China
| | - Yan Wang
- Department of Hepatic Surgery, The First Affiliated Hospital of Harbin Medical University, Key Laboratory of Hepatosplenic Surgery, Ministry of Education, Harbin, China
| | - Jiabei Wang
- Department of Hepatic Surgery, The First Affiliated Hospital of Harbin Medical University, Key Laboratory of Hepatosplenic Surgery, Ministry of Education, Harbin, China
| | - Guangchao Yang
- Department of Hepatic Surgery, The First Affiliated Hospital of Harbin Medical University, Key Laboratory of Hepatosplenic Surgery, Ministry of Education, Harbin, China
| | - Keyu Li
- Department of Hepatic Surgery, The First Affiliated Hospital of Harbin Medical University, Key Laboratory of Hepatosplenic Surgery, Ministry of Education, Harbin, China
| | - Ruipeng Song
- Department of Hepatic Surgery, The First Affiliated Hospital of Harbin Medical University, Key Laboratory of Hepatosplenic Surgery, Ministry of Education, Harbin, China
| | - Tongsen Zheng
- Department of Gastrointestinal Medical Oncology, The Affiliated Tumor Hospital of Harbin Medical University, Harbin, China
| | - Yingjian Liang
- Department of Hepatic Surgery, The First Affiliated Hospital of Harbin Medical University, Key Laboratory of Hepatosplenic Surgery, Ministry of Education, Harbin, China
| | - Shangha Pan
- Department of Hepatic Surgery, The First Affiliated Hospital of Harbin Medical University, Key Laboratory of Hepatosplenic Surgery, Ministry of Education, Harbin, China
| | - Xirui Liu
- Department of Hepatic Surgery, The First Affiliated Hospital of Harbin Medical University, Key Laboratory of Hepatosplenic Surgery, Ministry of Education, Harbin, China
| | - Mingxi Zhu
- Department of Hepatic Surgery, The First Affiliated Hospital of Harbin Medical University, Key Laboratory of Hepatosplenic Surgery, Ministry of Education, Harbin, China
| | - Yao Liu
- Department of Hepatic Surgery, The First Affiliated Hospital of Harbin Medical University, Key Laboratory of Hepatosplenic Surgery, Ministry of Education, Harbin, China
| | - Fanzheng Meng
- Department of Hepatic Surgery, The First Affiliated Hospital of Harbin Medical University, Key Laboratory of Hepatosplenic Surgery, Ministry of Education, Harbin, China
| | - Manzoor Mohsin
- Department of Hepatic Surgery, The First Affiliated Hospital of Harbin Medical University, Key Laboratory of Hepatosplenic Surgery, Ministry of Education, Harbin, China
| | - Yifeng Cui
- Department of Hepatic Surgery, The First Affiliated Hospital of Harbin Medical University, Key Laboratory of Hepatosplenic Surgery, Ministry of Education, Harbin, China
| | - Bo Zhang
- Department of Hepatic Surgery, The First Affiliated Hospital of Harbin Medical University, Key Laboratory of Hepatosplenic Surgery, Ministry of Education, Harbin, China
| | - Sharma Subash
- Department of Hepatic Surgery, The First Affiliated Hospital of Harbin Medical University, Key Laboratory of Hepatosplenic Surgery, Ministry of Education, Harbin, China
| | - Lianxin Liu
- Department of Hepatic Surgery, The First Affiliated Hospital of Harbin Medical University, Key Laboratory of Hepatosplenic Surgery, Ministry of Education, Harbin, China.
| |
Collapse
|
21
|
Chou TF, Chuang YT, Hsieh WC, Chang PY, Liu HY, Mo ST, Hsu TS, Miaw SC, Chen RH, Kimchi A, Lai MZ. Tumour suppressor death-associated protein kinase targets cytoplasmic HIF-1α for Th17 suppression. Nat Commun 2016; 7:11904. [PMID: 27312851 PMCID: PMC4915028 DOI: 10.1038/ncomms11904] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2015] [Accepted: 05/11/2016] [Indexed: 01/01/2023] Open
Abstract
Death-associated protein kinase (DAPK) is a tumour suppressor. Here we show that DAPK also inhibits T helper 17 (Th17) and prevents Th17-mediated pathology in a mouse model of autoimmunity. We demonstrate that DAPK specifically downregulates hypoxia-inducible factor 1α (HIF-1α). In contrast to the predominant nuclear localization of HIF-1α in many cell types, HIF-1α is located in both the cytoplasm and nucleus in T cells, allowing for a cytosolic DAPK–HIF-1α interaction. DAPK also binds prolyl hydroxylase domain protein 2 (PHD2) and increases HIF-1α-PHD2 association. DAPK thereby promotes the proline hydroxylation and proteasome degradation of HIF-1α. Consequently, DAPK deficiency leads to excess HIF-1α accumulation, enhanced IL-17 expression and exacerbated experimental autoimmune encephalomyelitis. Additional knockout of HIF-1α restores the normal differentiation of Dapk−/− Th17 cells and prevents experimental autoimmune encephalomyelitis development. Our results reveal a mechanism involving DAPK-mediated degradation of cytoplasmic HIF-1α, and suggest that raising DAPK levels could be used for treatment of Th17-associated inflammatory diseases. HIF-1α is critical for Th17 differentiation. Here the authors show that DAPK (Death-Associated Protein Kinase) inhibits Th17 differentiation and immunopathology in a mouse model of multiple sclerosis by promoting HIF1-α binding to its negative regulator PHD2.
Collapse
Affiliation(s)
- Ting-Fang Chou
- Graduate Institute of Life Sciences, National Defense Medical College, Taipei 11490, Taiwan.,Institute of Molecular Biology, Academia Sinica, Taipei 11529, Taiwan
| | - Ya-Ting Chuang
- Department of Medical Research, National Taiwan University Hospital, Taipei 10002, Taiwan
| | - Wan-Chen Hsieh
- Institute of Molecular Biology, Academia Sinica, Taipei 11529, Taiwan
| | - Pei-Yun Chang
- Institute of Molecular Biology, Academia Sinica, Taipei 11529, Taiwan
| | - Hsin-Yu Liu
- Institute of Molecular Biology, Academia Sinica, Taipei 11529, Taiwan
| | - Shu-Ting Mo
- Institute of Molecular Biology, Academia Sinica, Taipei 11529, Taiwan
| | - Tzu-Sheng Hsu
- Institute of Molecular Biology, Academia Sinica, Taipei 11529, Taiwan
| | - Shi-Chuen Miaw
- Institute of Immunology, National Taiwan University, Taipei 10057, Taiwan
| | - Ruey-Hwa Chen
- Institute of Biological Chemistry, Academia Sinica, Taipei 11529, Taiwan.,Institute of Molecular Medicine, National Taiwan University, Taipei 10057, Taiwan
| | - Adi Kimchi
- Department of Molecular Genetics, Weizmann Institute of Science, Rehovot 76100, Israel
| | - Ming-Zong Lai
- Graduate Institute of Life Sciences, National Defense Medical College, Taipei 11490, Taiwan.,Institute of Molecular Biology, Academia Sinica, Taipei 11529, Taiwan.,Institute of Immunology, National Taiwan University, Taipei 10057, Taiwan
| |
Collapse
|
22
|
Discovery of indirubin derivatives as new class of DRAK2 inhibitors from high throughput screening. Bioorg Med Chem Lett 2016; 26:2719-23. [PMID: 27106709 DOI: 10.1016/j.bmcl.2016.03.111] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2015] [Revised: 03/27/2016] [Accepted: 03/31/2016] [Indexed: 01/14/2023]
Abstract
DRAK2 is a serine/threonine kinase belonging to the death-associated protein kinase (DAPK) family and has emerged as a promising drug target for the treatment of autoimmune diseases and cancers. To identify small molecule inhibitors for DRAK2, we performed a high throughput screening campaign using in-house chemical library and identified indirubin-3'-monoximes as novel class of DRAK2 inhibitors. Among the compounds tested, compound 16 exhibited the most potent inhibitory activity against DRAK2 (IC50=0.003μM). We also propose that compound 16 may bind to the ATP-binding site of the enzyme based on enzyme kinetics and molecular docking studies.
Collapse
|
23
|
Harris TL, McGargill MA. Drak2 Does Not Regulate TGF-β Signaling in T Cells. PLoS One 2015; 10:e0123650. [PMID: 25951457 PMCID: PMC4423867 DOI: 10.1371/journal.pone.0123650] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2014] [Accepted: 02/10/2015] [Indexed: 12/31/2022] Open
Abstract
Drak2 is a serine/threonine kinase expressed highest in T cells and B cells. Drak2-/- mice are resistant to autoimmunity in mouse models of type 1 diabetes and multiple sclerosis. Resistance to these diseases occurs, in part, because Drak2 is required for the survival of autoreactive T cells that induce disease. However, the molecular mechanisms by which Drak2 affects T cell survival and autoimmunity are not known. A recent report demonstrated that Drak2 negatively regulated transforming growth factor-β (TGF-β) signaling in tumor cell lines. Thus, increased TGF-β signaling in the absence of Drak2 may contribute to the resistance to autoimmunity in Drak2-/- mice. Therefore, we examined if Drak2 functioned as a negative regulator of TGF-β signaling in T cells, and whether the enhanced susceptibility to death of Drak2-/- T cells was due to augmented TGF-β signaling. Using several in vitro assays to test TGF-β signaling and T cell function, we found that activation of Smad2 and Smad3, which are downstream of the TGF-β receptor, was similar between wildtype and Drak2-/- T cells. Furthermore, TGF-β-mediated effects on naïve T cell proliferation, activated CD8+ T cell survival, and regulatory T cell induction was similar between wildtype and Drak2-/- T cells. Finally, the increased susceptibility to death in the absence of Drak2 was not due to enhanced TGF-β signaling. Together, these data suggest that Drak2 does not function as a negative regulator of TGF-β signaling in primary T cells stimulated in vitro. It is important to investigate and discern potential molecular mechanisms by which Drak2 functions in order to better understand the etiology of autoimmune diseases, as well as to validate the use of Drak2 as a target for therapeutic treatment of these diseases.
Collapse
Affiliation(s)
- Tarsha L. Harris
- Department of Immunology, St. Jude Children’s Research Hospital, Memphis, Tennessee, United States of America
- Integrated Biomedical Sciences Program, University of Tennessee Health Science Center, Memphis, Tennessee, United States of America
| | - Maureen A. McGargill
- Department of Immunology, St. Jude Children’s Research Hospital, Memphis, Tennessee, United States of America
- Integrated Biomedical Sciences Program, University of Tennessee Health Science Center, Memphis, Tennessee, United States of America
- * E-mail:
| |
Collapse
|
24
|
Edwards BA, Harris TL, Floersh H, Lukens JR, Zaki MH, Vogel P, Kanneganti TD, Bui JD, McGargill MA. Drak2 is not required for tumor surveillance and suppression. Int Immunol 2015; 27:161-6. [PMID: 25568303 DOI: 10.1093/intimm/dxu146] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
Drak2 is a promising therapeutic target to treat organ-specific autoimmune diseases such as type 1 diabetes and multiple sclerosis without causing generalized immune suppression. Inhibition of Drak2 may also prevent graft rejection following organ transplantation. However, Drak2 may function as a critical tumor suppressor, which would challenge the prospect of targeting Drak2 for therapeutic treatment. Thus, we examined the susceptibility of Drak2 (-/-) mice in several tumor models. We show that Drak2 is not required to prevent tumor formation in a variety of settings. Therefore, Drak2 does not function as an essential tumor suppressor in in vivo tumor models. These data further validate Drak2 as a viable therapeutic target to treat autoimmune disease and graft rejection. Importantly, these data also indicate that while Drak2 may induce apoptosis when overexpressed in cell lines, it is not an essential tumor suppressor.
Collapse
Affiliation(s)
- Benjamin A Edwards
- Department of Immunology, St. Jude Children's Research Hospital, 262 Danny Thomas Place, MS 351, Memphis, TN 38105, USA
| | - Tarsha L Harris
- Department of Immunology, St. Jude Children's Research Hospital, 262 Danny Thomas Place, MS 351, Memphis, TN 38105, USA
| | - Helen Floersh
- Department of Immunology, St. Jude Children's Research Hospital, 262 Danny Thomas Place, MS 351, Memphis, TN 38105, USA
| | - John R Lukens
- Department of Immunology, St. Jude Children's Research Hospital, 262 Danny Thomas Place, MS 351, Memphis, TN 38105, USA
| | - Md Hasan Zaki
- Department of Immunology, St. Jude Children's Research Hospital, 262 Danny Thomas Place, MS 351, Memphis, TN 38105, USA
| | - Peter Vogel
- Department of Veterinary Pathology, St. Jude Children's Research Hospital, Memphis, TN 38105, USA
| | - Thirumala-Devi Kanneganti
- Department of Immunology, St. Jude Children's Research Hospital, 262 Danny Thomas Place, MS 351, Memphis, TN 38105, USA
| | - Jack D Bui
- Department of Pathology, University of California, San Diego, La Jolla, CA 92093, USA
| | - Maureen A McGargill
- Department of Immunology, St. Jude Children's Research Hospital, 262 Danny Thomas Place, MS 351, Memphis, TN 38105, USA
| |
Collapse
|
25
|
Abstract
Death-associated protein kinase (DAPK) is a tumor suppressor and negatively regulates several activation signals. Consistent with its potential anti-inflammatory activity, DAPK promotes the formation of IFN-γ-activated inhibitor of translation (GAIT) complex that suppresses the translation of selected inflammatory genes. DAPK has been found to inhibit tumor necrosis factor-α (TNF-α)- or lipopolysaccharides (LPS)-induced NF-κB activation and pro-inflammatory cytokine expression. Inflammation is always associated with T cell activation, while DAPK attenuates T cell activation by a selective suppression in T cell receptor-triggered NF-κB activation. Recent studies, however, also reveal a contribution of DAPK to pro-inflammatory processes. DAPK is shown to mediate pro-inflammatory signaling downstream of TNF-α, LPS, IL-17, or IL-32. In addition, DAPK is required for the full formation of NLRP3 inflammasome, essential for the generation of IL-1β and IL-18. These results suggest the complicated role of DAPK in the regulation of inflammation that is likely dependent on cell types and environmental cues.
Collapse
Affiliation(s)
- Ming-Zong Lai
- Institute of Molecular Biology, Academia Sinica, Taipei, 11529, Taiwan, ROC,
| | | |
Collapse
|
26
|
Gao LJ, Kovackova S, Sála M, Ramadori AT, De Jonghe S, Herdewijn P. Discovery of dual death-associated protein related apoptosis inducing protein kinase 1 and 2 inhibitors by a scaffold hopping approach. J Med Chem 2014; 57:7624-43. [PMID: 25178155 DOI: 10.1021/jm5007929] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
DRAK2 emerged as a promising drug target for the treatment of autoimmune diseases and to prevent graft rejection after organ transplantation. Screening of a compound library in a DRAK2 binding assay led to the identification of an isothiazolo[5,4-b]pyridine derivative as a novel ligand for DRAK2, displaying a Kd value of 1.6 μM. Subsequent medicinal chemistry work led to the discovery of a thieno[2,3-b]pyridine derivative with strong DRAK2 binding affinity (Kd = 9 nM). Moreover, this compound also behaves as a functional inhibitor of DRAK2 enzymatic activity, displaying an IC50 value of 0.82 μM, although lacking selectivity, when tested against DRAK1. This paper describes for the first time functionally active dual DRAK1 and DRAK2 inhibitors that can be used as starting point for the synthesis of chemical tool compounds to study DRAK1 and DRAK2 biology, or they can be considered as hit compounds for hit-to-lead optimization campaigns in drug discovery programs.
Collapse
Affiliation(s)
- Ling-Jie Gao
- Rega Institute for Medical Research, Laboratory of Medicinal Chemistry, KU Leuven , Minderbroedersstraat 10, 3000 Leuven, Belgium
| | | | | | | | | | | |
Collapse
|
27
|
Leonczak P, Gao LJ, Ramadori AT, Lescrinier E, Rozenski J, De Jonghe S, Herdewijn P. Synthesis and structure-activity relationship studies of 2-(1,3,4-oxadiazole-2(3H)-thione)-3-amino-5-arylthieno[2,3-b]pyridines as inhibitors of DRAK2. ChemMedChem 2014; 9:2587-601. [PMID: 25146684 DOI: 10.1002/cmdc.201402234] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2014] [Indexed: 12/28/2022]
Abstract
In recent years, DAPK-related apoptosis-inducing protein kinase 2 (DRAK2) has emerged as a promising target for the treatment of a variety of autoimmune diseases and for the prevention of graft rejection after organ transplantation. However, medicinal chemistry optimization campaigns for the discovery of novel small-molecule inhibitors of DRAK2 have not yet been published. Screening of a proprietary compound library led to the discovery of a benzothiophene analogue that displays an affinity constant (Kd) value of 0.25 μM. Variation of the core scaffold and of the substitution pattern afforded a series of 5-arylthieno[2,3-b]pyridines with strong binding affinity (Kd = 0.008 μM for the most potent representative). These compounds also show promising activity in a functional biochemical DRAK2 enzyme assay, with an IC50 value of 0.029 μM for the most potent congener. Selectivity profiling of the most potent compounds revealed that they lack selectivity within the DAPK family of kinases. However, one of the less potent analogues is a selective ligand for DRAK2 and can be used as starting point for the synthesis of selective and potent DRAK2 inhibitors.
Collapse
Affiliation(s)
- Piotr Leonczak
- KU Leuven, Rega Institute for Medical Research, Laboratory of Medicinal Chemistry, Minderbroedersstraat 10, 3000 Leuven (Belgium); KU Leuven, Interface Valorisation Platform, Kapucijnenvoer 33, 3000 Leuven (Belgium)
| | | | | | | | | | | | | |
Collapse
|
28
|
Fracchia KM, Pai CY, Walsh CM. Modulation of T Cell Metabolism and Function through Calcium Signaling. Front Immunol 2013; 4:324. [PMID: 24133495 PMCID: PMC3795426 DOI: 10.3389/fimmu.2013.00324] [Citation(s) in RCA: 74] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2013] [Accepted: 09/24/2013] [Indexed: 01/08/2023] Open
Abstract
As a vital second messenger in the activation of lymphocytes, the divalent cation Ca(2+) plays numerous roles in adaptive immune responses. Importantly, Ca(2+) signaling is essential for T cell activation, tolerance of self-antigens, and homeostasis. Supporting the essential role of Ca(2+) signaling in T cell biology, the Ca(2+) regulated protein phosphatase calcineurin is a key target of pharmacologic inhibition for preventing allograft rejection and for autoimmune therapy. Recent studies have highlighted the unique role of Stim1 and Orai1/2 proteins in the regulation of store-operated/calcium release activated calcium (CRAC) channels in the context of T cells. While Ca(2+) is known to modulate T cell activation via effects on calcineurin and its target, nuclear factor of activated T cells (NFAT), this second messenger also regulates other pathways, including protein kinase C, calmodulin kinases, and cytoskeletal proteins. Ca(2+) also modulates the unique metabolic changes that occur during in distinct T cell stages and subsets. Herein, we discuss the means by which Ca(2+) mobilization modulates cellular metabolism following T cell receptor ligation. Further, we highlight the crosstalk between mitochondrial metabolism, reactive oxygen species (ROS) generation, and CRAC channel activity. As a target of mitochondrial ROS and Ca(2+) regulation, we describe the involvement of the serine/threonine kinase DRAK2 in the context of these processes. Given the important roles for Ca(2+) dependent signaling and cellular metabolism in adaptive immune responses, the crosstalk between these pathways is likely to be important for the regulation of T cell activation, tolerance, and homeostasis.
Collapse
Affiliation(s)
- Kelley M Fracchia
- Department of Molecular Biology and Biochemistry, The Institute for Immunology, University of California Irvine , Irvine, CA , USA
| | | | | |
Collapse
|
29
|
Temmerman K, Simon B, Wilmanns M. Structural and functional diversity in the activity and regulation of DAPK-related protein kinases. FEBS J 2013; 280:5533-50. [PMID: 23745726 DOI: 10.1111/febs.12384] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2013] [Revised: 06/06/2013] [Accepted: 06/07/2013] [Indexed: 11/30/2022]
Abstract
Within the large group of calcium/calmodulin-dependent protein kinases (CAMKs) of the human kinome, there is a distinct branch of highly related kinases that includes three families: death-associated protein-related kinases, myosin light-chain-related kinases and triple functional domain protein-related kinases. In this review, we refer to these collectively as DMT kinases. There are several functional features that span the three families, such as a broad involvement in apoptotic processes, cytoskeletal association and cellular plasticity. Other CAMKs contain a highly conserved HRD motif, which is a prerequisite for kinase regulation through activation-loop phosphorylation, but in all 16 members of the DMT branch, this is replaced by an HF/LD motif. This DMT kinase signature motif substitutes phosphorylation-dependent active-site interactions with a local hydrophobic core that maintains an active kinase conformation. Only about half of the DMT kinases have an additional autoregulatory domain, C-terminal to the kinase domain that binds calcium/calmodulin in order to regulate kinase activity. Protein substrates have been identified for some of the DMT kinases, but little is known about the mechanism of recognition. Substrate conformation could be an equally important parameter in substrate recognition as specific preferences in sequence position. Taking the data together, this kinase branch encapsulates a treasure trove of features that renders it distinct from many other protein kinases and calls for future research activities in this field.
Collapse
|
30
|
Nagy ZS, Ross JA, Rodriguez G, Balint BL, Szeles L, Nagy L, Kirken RA. Genome wide mapping reveals PDE4B as an IL-2 induced STAT5 target gene in activated human PBMCs and lymphoid cancer cells. PLoS One 2013; 8:e57326. [PMID: 23451206 PMCID: PMC3581501 DOI: 10.1371/journal.pone.0057326] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2012] [Accepted: 01/21/2013] [Indexed: 11/18/2022] Open
Abstract
IL-2 is the primary growth factor for promoting survival and proliferation of activated T cells that occurs following engagement of the Janus Kinase (JAK)1–3/and Signal Transducer and Activator of Transcription (STAT) 5 signaling pathway. STAT5 has two isoforms: STAT5A and STAT5B (commonly referred to as STAT5) which, in T cells, play redundant roles transcribing cell cycle and survival genes. As such, inhibition of STAT5 by a variety of mechanisms can rapidly induce apoptosis in certain lymphoid tumor cells, suggesting that it and its target genes represent therapeutic targets to control certain lymphoid diseases. To search for these molecules we aligned IL-2 regulated genes detected by Affymetrix gene expression microarrays with the STAT5 cistrome identified by chip-on-ChIP analysis in an IL-2-dependent human leukemia cell line, Kit225. Select overlapping genes were then validated using qRT2PCR medium-throughput arrays in human PHA-activated PBMCs. Of 19 putative genes, one key regulator of T cell receptor signaling, PDE4B, was identified as a novel target, which was readily up-regulated at the protein level (3 h) in IL-2 stimulated, activated human PBMCs. Surprisingly, only purified CD8+ primary T-cells expressed PDE4B, but not CD4+ cells. Moreover, PDE4B was found to be highly expressed in CD4+ lymphoid cancer cells, which suggests that it may represent a physiological role unique to the CD8+ and lymphoid cancer cells and thus might represent a target for pharmaceutical intervention for certain lymphoid diseases.
Collapse
Affiliation(s)
- Zsuzsanna S Nagy
- Department of Biological Sciences, University of Texas at El Paso, El Paso, Texas, United States of America.
| | | | | | | | | | | | | |
Collapse
|
31
|
Yang KM, Kim W, Bae E, Gim J, Weist BM, Jung Y, Hyun JS, Hernandez JB, Leem SH, Park T, Jeong J, Walsh CM, Kim SJ. DRAK2 participates in a negative feedback loop to control TGF-β/Smads signaling by binding to type I TGF-β receptor. Cell Rep 2012; 2:1286-99. [PMID: 23122956 DOI: 10.1016/j.celrep.2012.09.028] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2012] [Revised: 08/17/2012] [Accepted: 09/24/2012] [Indexed: 12/24/2022] Open
Abstract
TGF-β1 is a multifunctional cytokine that mediates diverse biological processes. However, the mechanisms by which the intracellular signals of TGF-β1 are terminated are not well understood. Here, we demonstrate that DRAK2 serves as a TGF-β1-inducible antagonist of TGF-β signaling. TGF-β1 stimulation rapidly induces DRAK2 expression and enhances endogenous interaction of the type I TGF-β receptor with DRAK2, thereby blocking R-Smads recruitment. Depletion of DRAK2 expression markedly augmented the intensity and the extent of TGF-β1 responses. Furthermore, a high level of DRAK2 expression was observed in basal-like and HER2-enriched breast tumors and cell lines, and depletion of DRAK2 expression suppressed the tumorigenic ability of breast cancer cells. Thus, these studies define a function for DRAK2 as an intrinsic intracellular antagonist participating in the negative feedback loop to control TGF-β1 responses, and aberrant expression of DRAK2 increases tumorigenic potential, in part, through the inhibition of TGF-β1 tumor suppressor activity.
Collapse
Affiliation(s)
- Kyung-Min Yang
- CHA Cancer Institute, CHA University of Medicine and Science, Seoul 135-081, Korea
| | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
32
|
Weist BM, Hernandez JB, Walsh CM. Loss of DRAK2 signaling enhances allogeneic transplant survival by limiting effector and memory T cell responses. Am J Transplant 2012; 12:2220-7. [PMID: 22494341 PMCID: PMC3396732 DOI: 10.1111/j.1600-6143.2012.04056.x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Here, we demonstrate that loss of DRAK2 signaling significantly promotes the acceptance of allogeneic engraftment in two separate transplant models without promoting generalized immunosuppression. Drak2-/- T cells failed to reject allogeneic tumors, and were defective in rejecting Balb/C allogeneic skin grafts on C57BL6/J recipients. A significant fraction of alloreactive Drak2-/- T cells underwent apoptosis following activation, whereas enforced expression of Bcl-xL in Drak2-/- T cells restored allograft rejection. Formation of allogeneic memory was also greatly hampered in T cells lacking the Drak2 gene. Adoptive transfer of memory T cells from Drak2-/- mice failed to promote the rejection of allogeneic tumors, and such cells led to significantly delayed rejection of skin allografts in the Balb/C->C57BL/6J model. Costimulatory blockade by in vivo administration of Cytotoxic T-Lymphocyte Antigen 4 fusion protein (CTLA4-Ig) synergized with the DRAK2 deficiency and led to long-term allogeneic skin graft acceptance. Overall, these results demonstrate that DRAK2 plays an important role in primary and memory T cell responsiveness to allografts. Because previous studies have demonstrated that a loss of DRAK2 does not negatively impact antiviral immunity, the studies here underscore the potential utility of pharmacological blockade of DRAK2 to achieve transplant maintenance without the imposition of generalized immunosuppression.
Collapse
Affiliation(s)
- Brian M. Weist
- Department of Molecular Biology and Biochemistry, University of California, Irvine, California 92697-3900
- Institute for Immunology, University of California, Irvine, California 92697
| | - Jeniffer B. Hernandez
- Department of Molecular Biology and Biochemistry, University of California, Irvine, California 92697-3900
- Institute for Immunology, University of California, Irvine, California 92697
| | - Craig M. Walsh
- Department of Molecular Biology and Biochemistry, University of California, Irvine, California 92697-3900
- Institute for Immunology, University of California, Irvine, California 92697
| |
Collapse
|
33
|
Mao P, Hever MP, Niemaszyk LM, Haghkerdar JM, Yanco EG, Desai D, Beyrouthy MJ, Kerley-Hamilton JS, Freemantle SJ, Spinella MJ. Serine/threonine kinase 17A is a novel p53 target gene and modulator of cisplatin toxicity and reactive oxygen species in testicular cancer cells. J Biol Chem 2011; 286:19381-91. [PMID: 21489989 DOI: 10.1074/jbc.m111.218040] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Testicular cancer is highly curable with cisplatin-based therapy, and testicular cancer-derived human embryonal carcinoma (EC) cells undergo a p53-dominant transcriptional response to cisplatin. In this study, we have discovered that a poorly characterized member of the death-associated protein family of serine/threonine kinases, STK17A (also called DRAK1), is a novel p53 target gene. Cisplatin-mediated induction of STK17A in the EC cell line NT2/D1 was prevented with p53 siRNA. Furthermore, STK17A was induced with cisplatin in HCT116 and MCF10A cells but to a much lesser extent in isogenic p53-suppressed cells. A functional p53 response element that binds endogenous p53 in a cisplatin-dependent manner was identified 5 kb upstream of the first coding exon of STK17A. STK17A is not present in the mouse genome, but the closely related gene STK17B is induced with cisplatin in mouse NIH3T3 cells, although this induction is p53-independent. Interestingly, in human cells containing both STK17A and STK17B, only STK17A is induced with cisplatin. Knockdown of STK17A conferred resistance to cisplatin-induced growth suppression and apoptotic cell death in EC cells. This was associated with the up-regulation of detoxifying and antioxidant genes, including metallothioneins MT1H, MT1M, and MT1X that have previously been implicated in cisplatin resistance. In addition, knockdown of STK17A resulted in decreased cellular reactive oxygen species, whereas STK17A overexpression increased reactive oxygen species. In summary, we have identified STK17A as a novel direct target of p53 and a modulator of cisplatin toxicity and reactive oxygen species in testicular cancer cells.
Collapse
Affiliation(s)
- Pingping Mao
- Department of Pharmacology and Toxicology, Dartmouth Medical School, Hanover, New Hampshire 03755, USA
| | | | | | | | | | | | | | | | | | | |
Collapse
|
34
|
Togi S, Ikeda O, Kamitani S, Nakasuji M, Sekine Y, Muromoto R, Nanbo A, Oritani K, Kawai T, Akira S, Matsuda T. Zipper-interacting protein kinase (ZIPK) modulates canonical Wnt/beta-catenin signaling through interaction with Nemo-like kinase and T-cell factor 4 (NLK/TCF4). J Biol Chem 2011; 286:19170-7. [PMID: 21454679 DOI: 10.1074/jbc.m110.189829] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023] Open
Abstract
Zipper-interacting protein kinase (ZIPK) is a widely expressed serine/threonine kinase that has been implicated in apoptosis and transcriptional regulation. Here, we identified Nemo-like kinase (NLK) as a novel ZIPK-binding partner and found that ZIPK regulates NLK-mediated repression of canonical Wnt/β-catenin signaling. Indeed, siRNA-mediated reduction of endogenous ZIPK expression reduced Wnt/β-catenin signaling. Furthermore, ZIPK affected the formation of NLK-T-cell factor 4 (TCF4) complex. Importantly, ZIPK siRNA treatment in human colon carcinoma cells resulted in a reduction of β-catenin/TCF-mediated gene expression and cell growth. These results indicate that ZIPK may serve as a transcriptional regulator of canonical Wnt/β-catenin signaling through interaction with NLK/TCF4.
Collapse
Affiliation(s)
- Sumihito Togi
- Department of Immunology, Graduate School of Pharmaceutical Sciences, Hokkaido University, Sapporo 060-0812, Japan
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
35
|
Newton RH, Leverrier S, Srikanth S, Gwack Y, Cahalan MD, Walsh CM. Protein kinase D orchestrates the activation of DRAK2 in response to TCR-induced Ca2+ influx and mitochondrial reactive oxygen generation. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 2011; 186:940-50. [PMID: 21148796 PMCID: PMC3133617 DOI: 10.4049/jimmunol.1000942] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
DRAK2 is a serine/threonine kinase highly enriched in lymphocytes that raises the threshold for T cell activation and maintains T cell survival following productive activation. T cells lacking DRAK2 are prone to activation under suboptimal conditions and exhibit enhanced calcium responses to AgR stimulation. Despite this, mice lacking DRAK2 are resistant to organ-specific autoimmune diseases due to defective autoreactive T cell survival. DRAK2 kinase activity is induced by AgR signaling, and in this study we show that the induction of DRAK2 activity requires Ca(2+) influx through the Ca(2+) release-activated Ca(2+) channel formed from Orai1 subunits. Blockade of DRAK2 activity with the protein kinase D (PKD) inhibitor Gö6976 or expression of a kinase-dead PKD mutant prevented activation of DRAK2, whereas a constitutively active PKD mutant promoted DRAK2 function. Knockdown of PKD in T cells strongly blocked endogenous DRAK2 activation following TCR ligation, implicating PKD as an essential intermediate in the activation of DRAK2 by Ca(2+) influx. Furthermore, we identify DRAK2 as a novel substrate of PKD, and demonstrate that DRAK2 and PKD physically interact under conditions that activate PKD. Mitochondrial generation of reactive oxygen intermediates was necessary and sufficient for DRAK2 activation in response to Ca(2+) influx. Taken together, DRAK2 and PKD form a novel signaling module that controls calcium homeostasis following T cell activation.
Collapse
Affiliation(s)
- Ryan H. Newton
- Institute for Immunology, University of California, Irvine, Irvine, CA 92697
- Department of Molecular Biology and Biochemistry, University of California, Irvine, Irvine, CA 92697
| | - Sabrina Leverrier
- Institute for Immunology, University of California, Irvine, Irvine, CA 92697
- Department of Physiology and Biophysics, University of California, Irvine, Irvine, CA 92697
| | - Sonal Srikanth
- Department of Physiology, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA 90095
| | - Yousang Gwack
- Department of Physiology, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA 90095
| | - Michael D. Cahalan
- Institute for Immunology, University of California, Irvine, Irvine, CA 92697
- Department of Physiology and Biophysics, University of California, Irvine, Irvine, CA 92697
| | - Craig M. Walsh
- Institute for Immunology, University of California, Irvine, Irvine, CA 92697
- Department of Molecular Biology and Biochemistry, University of California, Irvine, Irvine, CA 92697
| |
Collapse
|
36
|
Neubueser D, Hipfner DR. Overlapping roles of Drosophila Drak and Rok kinases in epithelial tissue morphogenesis. Mol Biol Cell 2010; 21:2869-79. [PMID: 20573980 DOI: 10.1091/mbc.e10-04-0328] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
Dynamic regulation of cytoskeletal contractility through phosphorylation of the nonmuscle Myosin-II regulatory light chain (MRLC) provides an essential source of tension for shaping epithelial tissues. Rho GTPase and its effector kinase ROCK have been implicated in regulating MRLC phosphorylation in vivo, but evidence suggests that other mechanisms must be involved. Here, we report the identification of a single Drosophila homologue of the Death-associated protein kinase (DAPK) family, called Drak, as a regulator of MRLC phosphorylation. Based on analysis of null mutants, we find that Drak broadly promotes proper morphogenesis of epithelial tissues during development. Drak activity is largely redundant with that of the Drosophila ROCK orthologue, Rok, such that it is essential only when Rok levels are reduced. We demonstrate that these two kinases synergistically promote phosphorylation of Spaghetti squash (Sqh), the Drosophila MRLC orthologue, in vivo. The lethality of drak/rok mutants can be rescued by restoring Sqh activity, indicating that Sqh is the critical common effector of these two kinases. These results provide the first evidence that DAPK family kinases regulate actin dynamics in vivo and identify Drak as a novel component of the signaling networks that shape epithelial tissues.
Collapse
Affiliation(s)
- Dagmar Neubueser
- Institut de recherches cliniques de Montréal, Montreal, QC, Canada
| | | |
Collapse
|
37
|
Shaw PJ, Lukens JR, Burns S, Chi H, McGargill MA, Kanneganti TD. Cutting edge: critical role for PYCARD/ASC in the development of experimental autoimmune encephalomyelitis. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 2010; 184:4610-4. [PMID: 20368281 PMCID: PMC3001131 DOI: 10.4049/jimmunol.1000217] [Citation(s) in RCA: 123] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Multiple sclerosis is an autoimmune disease in which self-reactive T cells attack oligodendrocytes that myelinate axons in the CNS. Experimental autoimmune encephalomyelitis (EAE), an animal model of multiple sclerosis, is dependent on caspase-1; however, the role of Nod-like receptors upstream of caspase-1 is unknown. Danger- and pathogen-associated molecular patterns activate Nod-like receptor 3, which activates caspase-1 through the adaptor protein, apoptosis-associated speck-like protein containing CARD (ASC). We report that the progression of EAE is dependent on ASC and caspase-1 but not Nod-like receptor 3. ASC(-/-) mice were even more protected from the progression of EAE than were caspase-1(-/-) mice, suggesting that an inflammasome-independent function of ASC contributes to the progression of EAE. We found that CD4(+) T cells deficient in ASC exhibited impaired survival; accordingly, ASC(-/-) mice had fewer myelin oligodendrocyte glycoprotein-specific T cells in the draining lymph nodes and CNS.
Collapse
MESH Headings
- Animals
- Apoptosis/genetics
- Apoptosis/immunology
- CARD Signaling Adaptor Proteins/deficiency
- CARD Signaling Adaptor Proteins/genetics
- CARD Signaling Adaptor Proteins/physiology
- CD4-Positive T-Lymphocytes/immunology
- CD4-Positive T-Lymphocytes/metabolism
- CD4-Positive T-Lymphocytes/pathology
- Carrier Proteins/physiology
- Caspase 1/physiology
- Cell Proliferation
- Cell Survival/genetics
- Cell Survival/immunology
- Cells, Cultured
- Central Nervous System/immunology
- Central Nervous System/pathology
- Cytokines/biosynthesis
- Disease Progression
- Encephalomyelitis, Autoimmune, Experimental/enzymology
- Encephalomyelitis, Autoimmune, Experimental/genetics
- Encephalomyelitis, Autoimmune, Experimental/immunology
- Encephalomyelitis, Autoimmune, Experimental/prevention & control
- Lymph Nodes/immunology
- Lymph Nodes/pathology
- Lymphopenia/genetics
- Lymphopenia/immunology
- Lymphopenia/pathology
- Mice
- Mice, Inbred C57BL
- Mice, Knockout
- Myelin Proteins
- Myelin-Associated Glycoprotein/toxicity
- Myelin-Oligodendrocyte Glycoprotein
- NLR Family, Pyrin Domain-Containing 3 Protein
Collapse
Affiliation(s)
- Patrick J Shaw
- Department of Immunology, St. Jude Children's Research Hospital, Memphis, TN 38104, USA
| | | | | | | | | | | |
Collapse
|
38
|
Jeong SM, Lee C, Lee SK, Kim J, Seong RH. The SWI/SNF chromatin-remodeling complex modulates peripheral T cell activation and proliferation by controlling AP-1 expression. J Biol Chem 2009; 285:2340-50. [PMID: 19910461 DOI: 10.1074/jbc.m109.026997] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023] Open
Abstract
The SWI/SNF chromatin-remodeling complex has been implicated in the activation and proliferation of T cells. After T cell receptor signaling, the SWI/SNF complex rapidly associates with chromatin and controls gene expression in T cells. However, the process by which the SWI/SNF complex regulates peripheral T cell activation has not been elucidated. In this study, we show that the SWI/SNF complex regulates cytokine production and proliferation of T cells. During T cell activation, the SWI/SNF complex is recruited to the promoter of the transcription factor AP-1, and it increases the expression of AP-1. Increased expression of the SWI/SNF complex resulted in enhanced AP-1 activity, cytokine production, and proliferation of peripheral T cells, whereas knockdown of the SWI/SNF complex expression impaired the AP-1 expression and reduced the activation and proliferation of T cells. Moreover, mice that constitutively expressed the SWI/SNF complex in T cells were much more susceptible to experimentally induced autoimmune encephalomyelitis than the normal mice were. These results suggest that the SWI/SNF complex plays a critical role during T cell activation and subsequent immune responses.
Collapse
Affiliation(s)
- Seung Min Jeong
- Department of Biological Sciences, Institute of Molecular Biology and Genetics, and Research Center for Functional Cellulomics, Seoul National University, 599 Gwanangno, Gwanak-gu, Seoul 151-742, Korea
| | | | | | | | | |
Collapse
|
39
|
Doherty GA, Byrne SM, Austin SC, Scully GM, Sadlier DM, Neilan TG, Kay EW, Murray FE, Fitzgerald DJ. Regulation of the apoptosis-inducing kinase DRAK2 by cyclooxygenase-2 in colorectal cancer. Br J Cancer 2009; 101:483-91. [PMID: 19638987 PMCID: PMC2720240 DOI: 10.1038/sj.bjc.6605144] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Background: Cyclooxygenase-2 (COX-2) is over-expressed in colorectal cancer (CRC), rendering tumour cells resistant to apoptosis. Selective COX-2 inhibition is effective in CRC prevention, although having adverse cardiovascular effects, thus focus has shifted to downstream pathways. Methods: Microarray experiments identified genes regulated by COX-2 in HCA7 CRC cells. In vitro and in vivo regulation of DRAK2 (DAP kinase-related apoptosis-inducing kinase 2 or STK17β, an apoptosis-inducing kinase) by COX-2 was validated by qRT-PCR. Results: Inhibition of COX-2 induced apoptosis and enhanced DRAK2 expression in HCA7 cells (4.4-fold increase at 4 h by qRT-PCR, P=0.001), an effect prevented by co-administration of PGE2. DRAK2 levels were suppressed in a panel of human colorectal tumours (n=10) compared to normal mucosa, and showed inverse correlation with COX-2 expression (R=−0.68, R2=0.46, P=0.03). Administration of the selective COX-2 inhibitor rofecoxib to patients with CRC (n=5) induced DRAK2 expression in tumours (2.5-fold increase, P=0.01). In vitro silencing of DRAK2 by RNAi enhanced CRC cell survival following COX-2 inhibitor treatment. Conclusion: DRAK2 is a serine–threonine kinase implicated in the regulation of apoptosis and is negatively regulated by COX-2 in vitro and in vivo, suggesting a novel mechanism for the effect of COX-2 on cancer cell survival.
Collapse
Affiliation(s)
- G A Doherty
- Conway Institute of Biomolecular and Biomedical Research, University College Dublin, Dublin, Ireland.
| | | | | | | | | | | | | | | | | |
Collapse
|
40
|
Li Q, Smith AJ, Schacker TW, Carlis JV, Duan L, Reilly CS, Haase AT. Microarray analysis of lymphatic tissue reveals stage-specific, gene expression signatures in HIV-1 infection. THE JOURNAL OF IMMUNOLOGY 2009; 183:1975-82. [PMID: 19596987 DOI: 10.4049/jimmunol.0803222] [Citation(s) in RCA: 117] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Untreated HIV-1 infection progresses through acute and asymptomatic stages to AIDS. Although each of the three stages has well-known clinical, virologic, and immunologic characteristics, much less is known of the molecular mechanisms underlying each stage. In this study, we report lymphatic tissue microarray analyses, revealing for the first time stage-specific patterns of gene expression during HIV-1 infection. We show that although there is a common set of key genes with altered expression throughout all stages, each stage has a unique gene expression signature. The acute stage is most notably characterized by increased expression of hundreds of genes involved in immune activation, innate immune defenses (e.g., RIG-1, MDA-5, TLR7 and TLR8, PKR, APOBEC3B, 3F, 3G), adaptive immunity, and in the proapoptotic Fas-Fas ligand pathway. Yet, quite strikingly, the expression of nearly all acute stage genes return to baseline levels in the asymptomatic stage, accompanying partial control of infection. This transition from acute to asymptomatic stage is tied to increased expression of a diverse array of immunosuppressive genes (e.g., CLEC12B, ILT4, galectin-3, CD160, BCMA, FGL2, LAG3, GPNMB). In the AIDS stage, decreased expression of numerous genes involved in T cell signaling identifies genes contributing to T cell dysfunction. These common and stage-specific gene expression signatures identify potential molecular mechanisms underlying the host response and the slow, natural course of HIV-1 infection.
Collapse
Affiliation(s)
- Qingsheng Li
- Department of Microbiology, School of Public Health, University of Minnesota, Minneapolis, MN 55455, USA
| | | | | | | | | | | | | |
Collapse
|
41
|
Gatzka M, Newton RH, Walsh CM. Altered thymic selection and increased autoimmunity caused by ectopic expression of DRAK2 during T cell development. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 2009; 183:285-97. [PMID: 19542440 PMCID: PMC2724075 DOI: 10.4049/jimmunol.0803530] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Negative regulation of TCR signaling is an important mechanism enforcing immunological self-tolerance to prevent inappropriate activation of T cells and thus the development of autoimmune diseases. The lymphoid-restricted serine/threonine kinase death-associated protein-related apoptotic kinase-2 (DRAK2) raises the TCR activation threshold by targeting TCR-induced calcium mobilization in thymocytes and peripheral T cells and regulates positive thymic selection and peripheral T cell activation. Despite a hypersensitivity of peripheral drak2-deficient T cells, drak2-deficient mice are enigmatically resistant to induced autoimmunity in the model experimental autoimmune encephalomyelitis. To further evaluate the differential role of DRAK2 in central vs peripheral tolerance and to assess its impact on the development of autoimmune diseases, we have generated a transgenic (Tg) mouse strain ectopically expressing DRAK2 via the lck proximal promoter (1017-DRAK2 Tg mice). This transgene led to highest expression levels in double-positive thymocytes that are normally devoid of DRAK2. 1017-DRAK2 Tg mice displayed a reduction of single-positive CD4(+) and CD8(+) thymocytes in context with diminished negative selection in male HY TCR x 1017-DRAK2 Tg mice as well as peripheral T cell hypersensitivity, enhanced susceptibility to experimental autoimmune encephalomyelitis, and spontaneous autoimmunity. These findings suggest that alteration in thymocyte signaling thresholds impacts the sensitivity of peripheral T cell pools.
Collapse
MESH Headings
- Animals
- CD4-Positive T-Lymphocytes/immunology
- CD4-Positive T-Lymphocytes/pathology
- CD8-Positive T-Lymphocytes/immunology
- CD8-Positive T-Lymphocytes/pathology
- Cell Differentiation/genetics
- Cell Differentiation/immunology
- Clone Cells
- Down-Regulation/genetics
- Down-Regulation/immunology
- Encephalomyelitis, Autoimmune, Experimental/genetics
- Encephalomyelitis, Autoimmune, Experimental/immunology
- Encephalomyelitis, Autoimmune, Experimental/pathology
- Genetic Predisposition to Disease
- Immunophenotyping
- Lymphocyte Activation/genetics
- Lymphocyte Activation/immunology
- Male
- Mice
- Mice, Inbred C57BL
- Mice, Transgenic
- Organ Specificity/genetics
- Organ Specificity/immunology
- Protein Serine-Threonine Kinases/biosynthesis
- Protein Serine-Threonine Kinases/deficiency
- Protein Serine-Threonine Kinases/genetics
- Receptors, Antigen, T-Cell/antagonists & inhibitors
- Receptors, Antigen, T-Cell/physiology
- Signal Transduction/genetics
- Signal Transduction/immunology
- T-Lymphocyte Subsets/immunology
- T-Lymphocyte Subsets/metabolism
- T-Lymphocyte Subsets/pathology
- Thymus Gland/immunology
- Thymus Gland/metabolism
- Thymus Gland/pathology
Collapse
Affiliation(s)
- Martina Gatzka
- Department of Molecular Biology and Biochemistry/Institute for Immunology University of California, Irvine
| | - Ryan H. Newton
- Department of Molecular Biology and Biochemistry/Institute for Immunology University of California, Irvine
| | - Craig M. Walsh
- Department of Molecular Biology and Biochemistry/Institute for Immunology University of California, Irvine
| |
Collapse
|
42
|
Tang F, Chen Z, Ciszewski C, Setty M, Solus J, Tretiakova M, Ebert E, Han J, Lin A, Guandalini S, Groh V, Spies T, Green P, Jabri B. Cytosolic PLA2 is required for CTL-mediated immunopathology of celiac disease via NKG2D and IL-15. ACTA ACUST UNITED AC 2009; 206:707-19. [PMID: 19237603 PMCID: PMC2699120 DOI: 10.1084/jem.20071887] [Citation(s) in RCA: 73] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
IL-15 and NKG2D promote autoimmunity and celiac disease by arming cytotoxic T lymphocytes (CTLs) to cause tissue destruction. However, the downstream signaling events underlying these functional properties remain unclear. Here, we identify cytosolic phospholipase A2 (cPLA2) as a central molecule in NKG2D-mediated cytolysis in CTLs. Furthermore, we report that NKG2D induces, upon recognition of MIC+ target cells, the release of arachidonic acid (AA) by CTLs to promote tissue inflammation in association with target killing. Interestingly, IL-15, which licenses NKG2D-mediated lymphokine killer activity in CTLs, cooperates with NKG2D to induce cPLA2 activation and AA release. Finally, cPLA2 activation in intraepithelial CTLs of celiac patients provides an in vivo pathophysiological dimension to cPLA2 activation in CTLs. These results reveal an unrecognized link between NKG2D and tissue inflammation, which may underlie the emerging role of NKG2D in various immunopathological conditions and define new therapeutic targets.
Collapse
Affiliation(s)
- Fangming Tang
- Department of Pathology, University of Chicago, Chicago, IL 60637, USA
| | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
43
|
Ramos SJ, Hernandez JB, Gatzka M, Walsh CM. Enhanced T cell apoptosis within Drak2-deficient mice promotes resistance to autoimmunity. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 2008; 181:7606-16. [PMID: 19017949 PMCID: PMC2709975 DOI: 10.4049/jimmunol.181.11.7606] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Clonal expansion of T cells is vital to adaptive immunity, yet this process must be tightly controlled to prevent autoimmune disease. The serine/threonine kinase death-associated protein kinase-related apoptosis-inducing kinase 2 (DRAK2) is a negative regulator of TCR signaling and sets the threshold for the activation of naive and memory T cells and selected thymocytes. Despite enhanced T cell activation, Drak2(-/-) mice are resistant to experimental autoimmune encephalomyelitis, an autoimmune demyelinating disease that resembles multiple sclerosis. However, the basis for this autoimmune resistance is currently unknown. In this study, we show that, in the absence of DRAK2 signaling, T cells require greater tonic signaling for maintenance during clonal expansion. Following stimulation, Drak2(-/-) T cells were more sensitive to an intrinsic form of apoptosis that was prevented by CD28 ligation, homeostatic cytokines, or enforced Bcl-x(L) expression. T cell-specific Bcl-x(L) expression also restored the susceptibility of Drak2(-/-) mice to experimental autoimmune encephalomyelitis and enhanced thymic positive selection. These findings demonstrate that DRAK2 is selectively important for T cell survival and highlight the potential that DRAK2 blockade may lead to permanent autoimmune T cell destruction via intrinsic apoptosis pathways.
Collapse
MESH Headings
- Animals
- Apoptosis/genetics
- Apoptosis/immunology
- Autoimmunity/genetics
- Autoimmunity/immunology
- CD28 Antigens/genetics
- CD28 Antigens/immunology
- Cell Survival/genetics
- Cell Survival/immunology
- Cytokines/genetics
- Cytokines/immunology
- Encephalomyelitis, Autoimmune, Experimental/enzymology
- Encephalomyelitis, Autoimmune, Experimental/genetics
- Encephalomyelitis, Autoimmune, Experimental/immunology
- Immunologic Memory/genetics
- Immunologic Memory/immunology
- Lymphocyte Activation/genetics
- Lymphocyte Activation/immunology
- Mice
- Mice, Knockout
- Multiple Sclerosis/enzymology
- Multiple Sclerosis/genetics
- Multiple Sclerosis/immunology
- Protein Serine-Threonine Kinases/genetics
- Protein Serine-Threonine Kinases/immunology
- Receptors, Antigen, T-Cell/genetics
- Receptors, Antigen, T-Cell/immunology
- Signal Transduction/genetics
- Signal Transduction/immunology
- Thymus Gland/immunology
- bcl-X Protein/genetics
- bcl-X Protein/immunology
Collapse
Affiliation(s)
| | | | - Martina Gatzka
- Center for Immunology and the Department of Molecular Biology and Biochemistry, University of California, Irvine. Irvine, CA 92697-3900
| | - Craig M. Walsh
- Center for Immunology and the Department of Molecular Biology and Biochemistry, University of California, Irvine. Irvine, CA 92697-3900
| |
Collapse
|
44
|
McGargill MA, Choy C, Wen BG, Hedrick SM. Drak2 regulates the survival of activated T cells and is required for organ-specific autoimmune disease. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 2008; 181:7593-605. [PMID: 19017948 PMCID: PMC2792703 DOI: 10.4049/jimmunol.181.11.7593] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
Drak2 is a serine/threonine kinase expressed in T and B cells. The absence of Drak2 renders T cells hypersensitive to suboptimal stimulation, yet Drak2(-/-) mice are enigmatically resistant to experimental autoimmune encephalomyelitis, an animal model of multiple sclerosis. We show in this study that Drak2(-/-) mice were also completely resistant to type 1 diabetes when bred to the NOD strain of mice that spontaneously develop autoimmune diabetes. However, there was not a generalized suppression of the immune system, because Drak2(-/-) mice remained susceptible to other models of autoimmunity. Adoptive transfer experiments revealed that resistance to disease was intrinsic to the T cells and was due to a loss of T cell survival under conditions of chronic autoimmune stimulation. Importantly, the absence of Drak2 did not alter the survival of naive T cells, memory T cells, or T cells responding to an acute viral infection. These experiments reveal a distinction between the immune response to persistent self-encoded molecules and transiently present infectious agents. We present a model whereby T cell survival depends on a balance of TCR and costimulatory signals to explain how the absence of Drak2 affects autoimmune disease without generalized suppression of the immune system.
Collapse
Affiliation(s)
- Maureen A. McGargill
- Molecular Biology Section, Division of Biological Sciences, Department of Cellular and Molecular Medicine, University of California, San Diego, La Jolla, CA 92093
| | - Carmen Choy
- Molecular Biology Section, Division of Biological Sciences, Department of Cellular and Molecular Medicine, University of California, San Diego, La Jolla, CA 92093
| | - Ben G. Wen
- Department of Pharmacology, Genomics Institute of Novartis Research Foundation, San Diego, CA 92121
| | - Stephen M. Hedrick
- Molecular Biology Section, Division of Biological Sciences, Department of Cellular and Molecular Medicine, University of California, San Diego, La Jolla, CA 92093
| |
Collapse
|
45
|
Al-Qahtani A, Xu Z, Zan H, Walsh CM, Casali P. A role for DRAK2 in the germinal center reaction and the antibody response. Autoimmunity 2008; 41:341-52. [PMID: 18568639 PMCID: PMC3140869 DOI: 10.1080/08916930802170633] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
DAP-related apoptotic kinase-2 (DRAK2), a death-associated protein kinase family member, is highly expressed in B and T lymphocytes in the human and the mouse. To determine whether DRAK2 plays a role in B-cell activation and differentiation, we analyzed germinal centers (GCs) and the specific antibody response to NP in drak2-/- mice immunized with the thymus-dependent (TD) conjugated hapten NP16-CGG. In drak2-/- mice, spleen GCs were normal in size and morphology, but their number was reduced by as much as 5-fold, as compared to their wild-type littermates. This was not due to a defect in B-cell proliferation, as the BrdU uptake was comparable in DRAK2-deficient and wild-type B cells. Rather, the proportion of apoptotic GC B and T cells in drak2-/- mice was significantly higher than that in wild-type control mice, as shown by 7-AAD and terminal deoxynucleotide transferase dUTP nick end labeling (TUNEL) staining. In drak2-/- mice, the generation high affinity IgG antibodies was impaired in spite of the seemingly normal somatic hypermutation and class switch DNA recombination machineries in drak2-/- B cells. In NP16-CGG-immunized drak2-/- mice, T-cell-intrinsic Bcl-xL transgene expression increased the number of GCs and rescued the high affinity IgG response to NP. These findings suggest a novel role for DRAK2 in regulating the GC reaction and the response to TD antigens, perhaps through increased survival of T cells and enhanced B-cell positive selection. They also suggest that DRAK2-deficiency is not involved in regulating intrinsic B-cell apoptosis.
Collapse
Affiliation(s)
- Ahmed Al-Qahtani
- Center for Immunology, University of California, Irvine, CA, USA
| | | | | | | | | |
Collapse
|
46
|
Wang S, Welte T, McGargill M, Town T, Thompson J, Anderson JF, Flavell RA, Fikrig E, Hedrick SM, Wang T. Drak2 contributes to West Nile virus entry into the brain and lethal encephalitis. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 2008; 181:2084-91. [PMID: 18641347 PMCID: PMC2494872 DOI: 10.4049/jimmunol.181.3.2084] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Death-associated protein kinase-related apoptosis-inducing kinase-2 (Drak2), a member of the death-associated protein family of serine/threonine kinases, is specifically expressed in T and B cells. In the absence of Drak2, mice are resistant to experimental autoimmune encephalomyelitis due to a decrease in the number of cells infiltrating the CNS. In the present study, we investigated the role of Drak2 in West Nile virus (WNV)-induced encephalitis and found that Drak2(-/-) mice were also more resistant to lethal WNV infection than wild-type mice. Although Drak2(-/-) mice had an increase in the number of IFN-gamma-producing T cells in the spleen after infection, viral levels in the peripheral tissues were not significantly different between these two groups of mice. In contrast, there was a reduced viral load in the brains of Drak2(-/-) mice, which was accompanied by a decrease in the number of Drak2(-/-) CD4(+) and CD8(+) T cells in the brain following WNV infection. Moreover, we detected viral Ags in T cells isolated from the spleen or brain of WNV-infected mice. These results suggest that following a systemic infection, WNV might cross the blood brain barrier and enter the CNS by being carried by infected infiltrating T cells.
Collapse
Affiliation(s)
- Shuhui Wang
- Department of Microbiology, Immunology and Pathology, College of Veterinary Medicine & Biomedical Sciences, Colorado State University, Fort Collins, CO 80523
| | - Thomas Welte
- Department of Microbiology, Immunology and Pathology, College of Veterinary Medicine & Biomedical Sciences, Colorado State University, Fort Collins, CO 80523
| | - Maureen McGargill
- Department of Biology and Cancer Center, University of California-San Diego, La Jolla, CA 92093
| | - Terrence Town
- Section of Immunobiology, Yale University School of Medicine, 300 Cedar Street, New Haven, CT 06520
| | - Jesse Thompson
- Department of Microbiology, Immunology and Pathology, College of Veterinary Medicine & Biomedical Sciences, Colorado State University, Fort Collins, CO 80523
| | - John F Anderson
- Department of Entomology, Connecticut Agricultural Experiment Station, P. O. Box 1106, New Haven, CT 06504
| | - Richard A Flavell
- Section of Immunobiology, Yale University School of Medicine, 300 Cedar Street, New Haven, CT 06520
- The Howard Hughes Medical Institute, Yale University School of Medicine, 300 Cedar Street, New Haven, CT 06520
| | - Erol Fikrig
- The Howard Hughes Medical Institute, Yale University School of Medicine, 300 Cedar Street, New Haven, CT 06520
- Section of Infectious Diseases, Department of Internal Medicine, Yale University School of Medicine, 300 Cedar Street, New Haven, CT 06520
| | - Stephen M. Hedrick
- Department of Biology and Cancer Center, University of California-San Diego, La Jolla, CA 92093
| | - Tian Wang
- Department of Microbiology, Immunology and Pathology, College of Veterinary Medicine & Biomedical Sciences, Colorado State University, Fort Collins, CO 80523
| |
Collapse
|
47
|
Physical and functional interactions between ZIP kinase and UbcH5. Biochem Biophys Res Commun 2008; 372:708-12. [PMID: 18515077 DOI: 10.1016/j.bbrc.2008.05.113] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2008] [Accepted: 05/18/2008] [Indexed: 01/14/2023]
Abstract
Zipper-interacting protein kinase (ZIPK) is a widely expressed serine/threonine kinase that has been implicated in cell death and transcriptional regulation, but its mechanism of regulation remains unknown. In our previous study, we showed that leukemia inhibitory factor stimulated threonine-265 phosphorylation of ZIPK, thereby leading to phosphorylation and activation of signal transducer and activator of transcription 3. Here, we identified UbcH5c as a novel ZIPK-binding partner by yeast two-hybrid screening. Importantly, we found that UbcH5c induced ubiquitination of ZIPK. Small-interfering RNA-mediated reduction of endogenous UbcH5 expression decreased ZIPK ubiquitination. Furthermore, coexpression of UbcH5c with ZIPK influenced promyelocytic leukemia protein nuclear body (PML-NB) formation. These results suggest that UbcH5 regulates ZIPK accumulation in PML-NBs by interacting with ZIPK and stimulating its ubiquitination.
Collapse
|
48
|
Schaumburg CS, Gatzka M, Walsh CM, Lane TE. DRAK2 regulates memory T cell responses following murine coronavirus infection. Autoimmunity 2008; 40:483-8. [PMID: 17966037 DOI: 10.1080/08916930701651139] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
The contribution of DRAK2 [death-associated protein kinase (DAPK)-related apoptosis-inducing kinase 2] to anti-viral memory T cell responses following infection with mouse hepatitis virus (MHV) was examined. DRAK2 is a lymphoid-enriched serine/threonine kinase that is an important regulatory molecule involved in modulating T cell responses. Memory T cells derived from MHV-immunized Drak2(-/-) mice exhibited amplified proliferation and IFN-gamma secretion following stimulation with viral epitopes. Transfer of Drak2(-/-) memory T cells into Rag1(-/-) mice infected intracerebrally with MHV resulted in accelerated clearance of virus from the brain. Thus, DRAK2 may be a novel target for stimulating protective immunity to viral pathogens.
Collapse
Affiliation(s)
- Chris S Schaumburg
- Department of Molecular Biology and Biochemistry, University of California, Irvine, CA 92697-3900, USA
| | | | | | | |
Collapse
|
49
|
Chuang YT, Fang LW, Lin-Feng MH, Chen RH, Lai MZ. The Tumor Suppressor Death-Associated Protein Kinase Targets to TCR-Stimulated NF-κB Activation. THE JOURNAL OF IMMUNOLOGY 2008; 180:3238-49. [DOI: 10.4049/jimmunol.180.5.3238] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
|
50
|
Tpl2 and ERK transduce antiproliferative T cell receptor signals and inhibit transformation of chronically stimulated T cells. Proc Natl Acad Sci U S A 2008; 105:2987-92. [PMID: 18287049 DOI: 10.1073/pnas.0708381104] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The protein kinase encoded by the Tpl2 protooncogene plays an obligatory role in the transduction of Toll-like receptor and death receptor signals in macrophages, B cells, mouse embryo fibroblasts, and epithelial cells in culture and promotes inflammatory responses in animals. To address its role in T cell activation, we crossed the T cell receptor (TCR) transgene 2C, which recognizes class I MHC presented peptides, into the Tpl2(-/-) genetic background. Surprisingly, the TCR2C(tg/tg)/Tpl2(-/-) mice developed T cell lymphomas with a latency of 4-6 months. The tumor cells were consistently TCR2C(+)CD8(+)CD4(-), suggesting that they were derived either from chronically stimulated mature T cells or from immature single positive (ISP) cells. Further studies showed that the population of CD8(+) ISP cells was not expanded in the thymus of TCR2C(tg/tg)/Tpl2(-/-) mice, making the latter hypothesis unlikely. Mature peripheral T cells of Tpl2(-/-) mice were defective in ERK activation and exhibited enhanced proliferation after TCR stimulation. The same cells were defective in the induction of CTLA4, a negative regulator of the T cell response, which is induced by TCR signals via ERK. These findings suggest that Tpl2 functions normally in a feedback loop that switches off the T cell response to TCR stimulation. As a result, Tpl2, a potent oncogene, functions as a tumor suppressor gene in chronically stimulated T cells.
Collapse
|