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Xu SJ, Chen JH, Chang S, Li HL. The role of miRNAs in T helper cell development, activation, fate decisions and tumor immunity. Front Immunol 2024; 14:1320305. [PMID: 38264670 PMCID: PMC10803515 DOI: 10.3389/fimmu.2023.1320305] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2023] [Accepted: 12/20/2023] [Indexed: 01/25/2024] Open
Abstract
T helper (Th) cells are central members of adaptive immunity and comprise the last line of defense against pathogen infection and malignant cell invasion by secreting specific cytokines. These cytokines then attract or induce the activation and differentiation of other immune cells, including antibody-producing B cells and cytotoxic CD8+ T cells. Therefore, the bidirectional communication between Th cells and tumor cells and their positioning within the tumor microenvironment (TME), especially the tumor immune microenvironment (TIME), sculpt the tumor immune landscape, which affects disease initiation and progression. The type, number, and condition of Th cells in the TME and TIME strongly affect tumor immunity, which is precisely regulated by key effectors, such as granzymes, perforins, cytokines, and chemokines. Moreover, microRNAs (miRNAs) have emerged as important regulators of Th cells. In this review, we discuss the role of miRNAs in regulating Th cell mediated adaptive immunity, focusing on the development, activation, fate decisions, and tumor immunity.
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Affiliation(s)
- Shi-Jun Xu
- Department of Interventional Radiology, The Affiliated Cancer Hospital of Zhengzhou University, Henan Cancer Hospital, Zhengzhou, Henan, China
- Henan Medical Device Engineering Research Center of Interventional Therapy for Non-vascular Tumors, Henan Cancer Hospital, Zhengzhou, Henan, China
| | - Jin-Hua Chen
- Department of Pharmacy, The Affiliated Cancer Hospital of Zhengzhou University, Henan Cancer Hospital, Zhengzhou, Henan, China
| | - Suhwan Chang
- Department of Physiology, University of Ulsan College of Medicine, Asan Medical Center, Seoul, Republic of Korea
| | - Hai-Liang Li
- Department of Interventional Radiology, The Affiliated Cancer Hospital of Zhengzhou University, Henan Cancer Hospital, Zhengzhou, Henan, China
- Henan Medical Device Engineering Research Center of Interventional Therapy for Non-vascular Tumors, Henan Cancer Hospital, Zhengzhou, Henan, China
- Department of Radiology, The Affiliated Cancer Hospital of Zhengzhou University, Henan Cancer Hospital, Zhengzhou, Henan, China
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Christofi P, Pantazi C, Psatha N, Sakellari I, Yannaki E, Papadopoulou A. Promises and Pitfalls of Next-Generation Treg Adoptive Immunotherapy. Cancers (Basel) 2023; 15:5877. [PMID: 38136421 PMCID: PMC10742252 DOI: 10.3390/cancers15245877] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2023] [Revised: 12/13/2023] [Accepted: 12/14/2023] [Indexed: 12/24/2023] Open
Abstract
Regulatory T cells (Tregs) are fundamental to maintaining immune homeostasis by inhibiting immune responses to self-antigens and preventing the excessive activation of the immune system. Their functions extend beyond immune surveillance and subpopulations of tissue-resident Treg cells can also facilitate tissue repair and homeostasis. The unique ability to regulate aberrant immune responses has generated the concept of harnessing Tregs as a new cellular immunotherapy approach for reshaping undesired immune reactions in autoimmune diseases and allo-responses in transplantation to ultimately re-establish tolerance. However, a number of issues limit the broad clinical applicability of Treg adoptive immunotherapy, including the lack of antigen specificity, heterogeneity within the Treg population, poor persistence, functional Treg impairment in disease states, and in vivo plasticity that results in the loss of suppressive function. Although the early-phase clinical trials of Treg cell therapy have shown the feasibility and tolerability of the approach in several conditions, its efficacy has remained questionable. Leveraging the smart tools and platforms that have been successfully developed for primary T cell engineering in cancer, the field has now shifted towards "next-generation" adoptive Treg immunotherapy, where genetically modified Treg products with improved characteristics are being generated, as regards antigen specificity, function, persistence, and immunogenicity. Here, we review the state of the art on Treg adoptive immunotherapy and progress beyond it, while critically evaluating the hurdles and opportunities towards the materialization of Tregs as a living drug therapy for various inflammation states and the broad clinical translation of Treg therapeutics.
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Affiliation(s)
- Panayiota Christofi
- Gene and Cell Therapy Center, Hematopoietic Cell Transplantation Unit, Hematology Department, George Papanikolaou Hospital, 57010 Thessaloniki, Greece; (P.C.); (C.P.); (I.S.); (E.Y.)
- University General Hospital of Patras, 26504 Rio, Greece
| | - Chrysoula Pantazi
- Gene and Cell Therapy Center, Hematopoietic Cell Transplantation Unit, Hematology Department, George Papanikolaou Hospital, 57010 Thessaloniki, Greece; (P.C.); (C.P.); (I.S.); (E.Y.)
- Department of Genetics, Development and Molecular Biology, School of Biology, Aristotle University of Thessaloniki, 54124 Thessaloniki, Greece;
- Institute of Applied Biosciences (INAB), Centre for Research and Technology Hellas (CERTH), 57001 Thessaloniki, Greece
| | - Nikoleta Psatha
- Department of Genetics, Development and Molecular Biology, School of Biology, Aristotle University of Thessaloniki, 54124 Thessaloniki, Greece;
| | - Ioanna Sakellari
- Gene and Cell Therapy Center, Hematopoietic Cell Transplantation Unit, Hematology Department, George Papanikolaou Hospital, 57010 Thessaloniki, Greece; (P.C.); (C.P.); (I.S.); (E.Y.)
| | - Evangelia Yannaki
- Gene and Cell Therapy Center, Hematopoietic Cell Transplantation Unit, Hematology Department, George Papanikolaou Hospital, 57010 Thessaloniki, Greece; (P.C.); (C.P.); (I.S.); (E.Y.)
- Department of Medicine, University of Washington, Seattle, WA 98195-7710, USA
| | - Anastasia Papadopoulou
- Gene and Cell Therapy Center, Hematopoietic Cell Transplantation Unit, Hematology Department, George Papanikolaou Hospital, 57010 Thessaloniki, Greece; (P.C.); (C.P.); (I.S.); (E.Y.)
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Gross S, Womer L, Kappes DJ, Soboloff J. Multifaceted control of T cell differentiation by STIM1. Trends Biochem Sci 2023; 48:1083-1097. [PMID: 37696713 PMCID: PMC10787584 DOI: 10.1016/j.tibs.2023.08.006] [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: 03/15/2023] [Revised: 08/08/2023] [Accepted: 08/18/2023] [Indexed: 09/13/2023]
Abstract
In T cells, stromal interaction molecule (STIM) and Orai are dispensable for conventional T cell development, but critical for activation and differentiation. This review focuses on novel STIM-dependent mechanisms for control of Ca2+ signals during T cell activation and its impact on mitochondrial function and transcriptional activation for control of T cell differentiation and function. We highlight areas that require further work including the roles of plasma membrane Ca2+ ATPase (PMCA) and partner of STIM1 (POST) in controlling Orai function. A major knowledge gap also exists regarding the independence of T cell development from STIM and Orai, despite compelling evidence that it requires Ca2+ signals. Resolving these and other outstanding questions ensures that the field will remain active for many years to come.
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Affiliation(s)
- Scott Gross
- Fels Cancer Institute for Personalized Medicine, Lewis Katz School of Medicine at Temple University, Philadelphia, PA, 19140, USA
| | - Lauren Womer
- Fels Cancer Institute for Personalized Medicine, Lewis Katz School of Medicine at Temple University, Philadelphia, PA, 19140, USA
| | | | - Jonathan Soboloff
- Fels Cancer Institute for Personalized Medicine, Lewis Katz School of Medicine at Temple University, Philadelphia, PA, 19140, USA; Department of Cancer and Cellular Biology, Lewis Katz School of Medicine at Temple University, Philadelphia, PA, 19140, USA.
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Dou D, Ji Y, Zheng J, Li J, Zhu X, Tang S, Wang H, Li Q, Jing H. A New Role for Conivaptan in Ulcerative Colitis in Mice: Inhibiting Differentiation of CD4 +T Cells into Th1 Cells. Dig Dis Sci 2022; 67:3683-3692. [PMID: 34751838 DOI: 10.1007/s10620-021-07300-y] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/01/2021] [Accepted: 10/18/2021] [Indexed: 12/11/2022]
Abstract
BACKGROUND Conivaptan, a nonselective antagonist of vasopressin receptors V1a and V2, is the first drug of this class to be used for treating euvolemic and hypervolemic hyponatremia. Recently, increasing evidence supports the involvement of vasopressin in immune responses. AIMS In this study, we investigated the effect of conivaptan on the modulation of CD4+ T cell homeostasis and the progression of experimental colitis. METHODS The expression of the V1a receptor on CD4+ T cells was detected by immunofluorescence and western blot. The subset of isolated CD4+ T cells were examined after arginine vasopressin (AVP) incubation. CD4+ T cells were injected into DNBS-induced mice through the tail vein. The severity of colitis was evaluated according to weight, disease activity index (DAI), and morphological injury. Intracellular Ca2+ ([Ca2+]i) signaling in CD4+ T cells was measured using the Fluo-3 AM loading method. T-bet and IFN-γ mRNAs in the colon were detected by real-time polymerase chain reaction (qPCR). RESULTS We found that CD4+ T cells expressed the V1a receptor. Activation of the V1a receptor significantly promoted the differentiation of CD4+ T cells into T helper 1 (Th1) cells. This process was blocked by conivaptan treatment. However, the activation of the V1a receptor did not evoke an increase in [Ca2+]i in CD4+ T cells. Notably, conivaptan markedly alleviated body weight loss, pathological damage, and expression of T-bet and IFN-γ in the colon of DNBS-treated mice. CONCLUSIONS For the first time, we report that conivaptan attenuated colitis by inhibiting the differentiation of CD4+ T cells into Th1 cells. Mechanistically, the anti-inflammatory role of conivaptan is independent of [Ca2+]i.
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Affiliation(s)
- Dandan Dou
- Department of Pathology, Shandong Provincial Hospital affiliated to Shandong First Medical University, Jinan, 250021, China.,Department of Physiology, School of Basic Medical Science, Shandong University, Jinan, China
| | - Yuge Ji
- Department of Physiology, School of Basic Medical Science, Shandong University, Jinan, China
| | - Junjie Zheng
- Department of Physiology, School of Basic Medical Science, Shandong University, Jinan, China
| | - Jingxin Li
- Department of Physiology, School of Basic Medical Science, Shandong University, Jinan, China
| | - Xiaolong Zhu
- Department of Surgery, Shandong Provincial Hospital affiliated to Shandong First Medical University, Jinan, China
| | - Shuhai Tang
- Department of Anesthesiology, Qilu Hospital of Shandong University, Jinan, China
| | - Hongjuan Wang
- Department of Gastroenterology, The Second Hospital, Cheeloo College of Medicine, Shandong University, Jinan, China
| | - Qin Li
- Department of Physiology, School of Basic Medical Science, Shandong University, Jinan, China
| | - Haiyan Jing
- Department of Pathology, Shandong Provincial Hospital affiliated to Shandong First Medical University, Jinan, 250021, China.
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Berry CT, May MJ, Freedman BD. Analysis of Calcium Control of Canonical NF-κB Signaling in B Lymphocytes. Methods Mol Biol 2021; 2366:145-164. [PMID: 34236637 DOI: 10.1007/978-1-0716-1669-7_9] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
The central role of calcium (Ca2+) signaling in lymphocyte development and acquisition of functional immunity and tolerance is well established. Ca2+ signals are initiated upon antigen binding to cognate receptors on lymphocytes that trigger store operated Ca2+ entry (SOCE). The underlying mechanism of SOCE in lymphocytes involves TCR and BCR mediated activation of Stromal Interaction Molecule 1 and 2 (STIM1/2) embedded in the ER membrane. Once activated, STIM proteins oligomerize and re-localize to ER domains juxtaposed to the plasma membrane where they activate Orai channels to allow Ca2+ to enter the cell across the plasma membrane. Importantly, STIM/Orai-dependent Ca2+ signals guide antigen induced lymphocyte development and function principally by regulating the activity of transcription factors.The most widely studied of these transcription factors is the Nuclear Factor of Activated T cells (NFAT). NFAT is expressed ubiquitously and the mechanism by which Ca2+ regulates NFAT activation and signaling is well known. By contrast, a mechanistic understanding of how Ca2+ signals also shape the activation and specificity of NF-κB to control the expression of pro-inflammatory genes has lagged. Here we discuss the methodology used to investigate Ca2+ dependent mechanisms of NF-κB activation in lymphocytes. Our approach focuses on three main areas of signal transduction and signaling: (1) antigen receptor engagement and Ca2+ dependent initiation of NF-kB signaling, (2) Ca2+ dependent induction of NF-κB heterodimer activation and nuclear localization, and (3) and how Ca2+ regulates NF-κB dependent expression of target genes and proteins.
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Affiliation(s)
- Corbett T Berry
- Department of Pathobiology, The University of Pennsylvania School of Veterinary Medicine, Philadelphia, PA, USA
| | - Michael J May
- Department of Biomedical Sciences, The University of Pennsylvania School of Veterinary Medicine, Philadelphia, PA, USA
| | - Bruce D Freedman
- Department of Pathobiology, The University of Pennsylvania School of Veterinary Medicine, Philadelphia, PA, USA.
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Abstract
Ca2+ is a ubiquitous and dynamic second messenger molecule that is induced by many factors including receptor activation, environmental factors, and voltage, leading to pleiotropic effects on cell function including changes in migration, metabolism and transcription. As such, it is not surprising that aberrant regulation of Ca2+ signals can lead to pathological phenotypes, including cancer progression. However, given the highly context-specific nature of Ca2+-dependent changes in cell function, delineation of its role in cancer has been a challenge. Herein, we discuss the distinct roles of Ca2+ signaling within and between each type of cancer, including consideration of the potential of therapeutic strategies targeting these signaling pathways.
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Affiliation(s)
- Scott Gross
- Fels Institute for Cancer Research and Molecular Biology, Lewis Katz School of Medicine at Temple University, Philadelphia, PA, United States
| | - Pranava Mallu
- Fels Institute for Cancer Research and Molecular Biology, Lewis Katz School of Medicine at Temple University, Philadelphia, PA, United States
| | - Hinal Joshi
- Fels Institute for Cancer Research and Molecular Biology, Lewis Katz School of Medicine at Temple University, Philadelphia, PA, United States
| | - Bryant Schultz
- Fels Institute for Cancer Research and Molecular Biology, Lewis Katz School of Medicine at Temple University, Philadelphia, PA, United States
| | - Christina Go
- Fels Institute for Cancer Research and Molecular Biology, Lewis Katz School of Medicine at Temple University, Philadelphia, PA, United States
| | - Jonathan Soboloff
- Fels Institute for Cancer Research and Molecular Biology, Lewis Katz School of Medicine at Temple University, Philadelphia, PA, United States; Department of Medical Genetics & Molecular Biochemistry, Lewis Katz School of Medicine at Temple University, Philadelphia, PA, United States.
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7
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STIM- and Orai-mediated calcium entry controls NF-κB activity and function in lymphocytes. Cell Calcium 2018; 74:131-143. [PMID: 30048879 DOI: 10.1016/j.ceca.2018.07.003] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2018] [Revised: 07/09/2018] [Accepted: 07/09/2018] [Indexed: 12/24/2022]
Abstract
The central role of Ca2+ signaling in the development of functional immunity and tolerance is well established. These signals are initiated by antigen binding to cognate receptors on lymphocytes that trigger store operated Ca2+ entry (SOCE). The underlying mechanism of SOCE in lymphocytes involves TCR and BCR mediated activation of Stromal Interaction Molecule 1 and 2 (STIM1/2) molecules embedded in the ER membrane leading to their activation of Orai channels in the plasma membrane. STIM/Orai dependent Ca2+ signals guide key antigen induced lymphocyte development and function principally through direct regulation of Ca2+ dependent transcription factors. The role of Ca2+ signaling in NFAT activation and signaling is well known and has been studied extensively, but a wide appreciation and mechanistic understanding of how Ca2+ signals also shape the activation and specificity of NF-κB dependent gene expression has lagged. Here we discuss and interpret what is known about Ca2+ dependent mechanisms of NF-kB activation, including what is known and the gaps in our understanding of how these signals control lymphocyte development and function.
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8
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Facilitation of hippocampal long-term potentiation and reactivation of latent HIV-1 via AMPK activation: Common mechanism of action linking learning, memory, and the potential eradication of HIV-1. Med Hypotheses 2018; 116:61-73. [DOI: 10.1016/j.mehy.2018.04.018] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2017] [Revised: 10/27/2017] [Accepted: 04/20/2018] [Indexed: 12/31/2022]
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9
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Hoefig KP, Heissmeyer V. Posttranscriptional regulation of T helper cell fate decisions. J Cell Biol 2018; 217:2615-2631. [PMID: 29685903 PMCID: PMC6080923 DOI: 10.1083/jcb.201708075] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2017] [Revised: 02/19/2018] [Accepted: 04/10/2018] [Indexed: 12/15/2022] Open
Abstract
Hoefig and Heissmeyer review how microRNAs, long noncoding RNAs, RNA-binding proteins, and ubiquitin-modifying enzymes regulate T helper cell differentiation downstream of transcription. T helper cell subsets orchestrate context- and pathogen-specific responses of the immune system. They mostly do so by secreting specific cytokines that attract or induce activation and differentiation of other immune or nonimmune cells. The differentiation of T helper 1 (Th1), Th2, T follicular helper, Th17, and induced regulatory T cell subsets from naive T cells depends on the activation of intracellular signal transduction cascades. These cascades originate from T cell receptor and costimulatory receptor engagement and also receive critical input from cytokine receptors that sample the cytokine milieu within secondary lymphoid organs. Signal transduction then leads to the expression of subset-specifying transcription factors that, in concert with other transcription factors, up-regulate downstream signature genes. Although regulation of transcription is important, recent research has shown that posttranscriptional and posttranslational regulation can critically shape or even determine the outcome of Th cell differentiation. In this review, we describe how specific microRNAs, long noncoding RNAs, RNA-binding proteins, and ubiquitin-modifying enzymes regulate their targets to skew cell fate decisions.
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Affiliation(s)
- Kai P Hoefig
- Research Unit Molecular Immune Regulation, Helmholtz Zentrum München, München, Germany
| | - Vigo Heissmeyer
- Research Unit Molecular Immune Regulation, Helmholtz Zentrum München, München, Germany .,Institute for Immunology at the Biomedical Center, Ludwig-Maximilians-Universität München, Planegg-Martinsried, Germany
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Simulated annealing molecular dynamics and ligand-receptor contacts analysis for pharmacophore modeling. Future Med Chem 2017; 9:1141-1159. [PMID: 28722471 DOI: 10.4155/fmc-2017-0061] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
AIM Ligand-based pharmacophore modeling requires long list of inhibitors, while pharmacophores based on single ligand-receptor crystallographic structure can be too restricted or promiscuous. METHODOLOGY This prompted us to combine simulated annealing molecular dynamics (SAMD) with ligand-receptor contacts analysis as means to construct pharmacophore model(s) from single ligand-receptor complex. Ligand-receptor contacts that survive numerous heating-cooling SAMD cycles are considered critical and are used to guide pharmacophore development. RESULTS This methodology was implemented to develop pharmacophores for acetylcholinesterase and protein kinase C-θ. The resulting models were validated by receiver-operating characteristic analysis and in vitro bioassay. Assay identified four new protein kinase C-θ inhibitors among captured hits, two of which exhibited nanomolar potencies. CONCLUSION The results illustrate the ability of the new method to extract valid pharmacophores from single ligand-protein complex.
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11
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Finley J. Elimination of cancer stem cells and reactivation of latent HIV-1 via AMPK activation: Common mechanism of action linking inhibition of tumorigenesis and the potential eradication of HIV-1. Med Hypotheses 2017; 104:133-146. [PMID: 28673572 DOI: 10.1016/j.mehy.2017.05.032] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2016] [Revised: 02/28/2017] [Accepted: 05/26/2017] [Indexed: 12/25/2022]
Abstract
Although promising treatments are currently in development to slow disease progression and increase patient survival, cancer remains the second leading cause of death in the United States. Cancer treatment modalities commonly include chemoradiation and therapies that target components of aberrantly activated signaling pathways. However, treatment resistance is a common occurrence and recent evidence indicates that the existence of cancer stem cells (CSCs) may underlie the limited efficacy and inability of current treatments to effectuate a cure. CSCs, which are largely resistant to chemoradiation therapy, are a subpopulation of cancer cells that exhibit characteristics similar to embryonic stem cells (ESCs), including self-renewal, multi-lineage differentiation, and the ability to initiate tumorigenesis. Interestingly, intracellular mechanisms that sustain quiescence and promote self-renewal in adult stem cells (ASCs) and CSCs likely also function to maintain latency of HIV-1 in CD4+ memory T cells. Although antiretroviral therapy is highly effective in controlling HIV-1 replication, the persistence of latent but replication-competent proviruses necessitates the development of compounds that are capable of selectively reactivating the latent virus, a method known as the "shock and kill" approach. Homeostatic proliferation in central CD4+ memory T (TCM) cells, a memory T cell subset that exhibits limited self-renewal and differentiation and is a primary reservoir for latent HIV-1, has been shown to reinforce and stabilize the latent reservoir in the absence of T cell activation and differentiation. HIV-1 has also been found to establish durable and long-lasting latency in a recently discovered subset of CD4+ T cells known as T memory stem (TSCM) cells. TSCM cells, compared to TCM cells, exhibit stem cell properties that more closely match those of ESCs and ASCs, including self-renewal and differentiation into all memory T cell subsets. It is our hypothesis that activation of AMPK, a master regulator of cellular metabolism that plays a critical role in T cell activation and differentiation of ESCs and ASCs, will lead to both T cell activation-induced latent HIV-1 reactivation, facilitating virus destruction, as well as "activation", differentiation, and/or apoptosis of CSCs, thus inhibiting tumorigenesis. We also propose the novel observation that compounds that have been shown to both facilitate latent HIV-1 reactivation and promote CSC differentiation/apoptosis (e.g. bryostatin-1, JQ1, metformin, butyrate, etc.) likely do so through a common mechanism of AMPK activation.
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Affiliation(s)
- Jahahreeh Finley
- Finley BioSciences, 9900 Richmond Avenue, #823, Houston, TX 77042-4539, United States.
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Ruffo E, Malacarne V, Larsen SE, Das R, Patrussi L, Wülfing C, Biskup C, Kapnick SM, Verbist K, Tedrick P, Schwartzberg PL, Baldari CT, Rubio I, Nichols KE, Snow AL, Baldanzi G, Graziani A. Inhibition of diacylglycerol kinase α restores restimulation-induced cell death and reduces immunopathology in XLP-1. Sci Transl Med 2016; 8:321ra7. [PMID: 26764158 DOI: 10.1126/scitranslmed.aad1565] [Citation(s) in RCA: 35] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
X-linked lymphoproliferative disease (XLP-1) is an often-fatal primary immunodeficiency associated with the exuberant expansion of activated CD8(+) T cells after Epstein-Barr virus (EBV) infection. XLP-1 is caused by defects in signaling lymphocytic activation molecule (SLAM)-associated protein (SAP), an adaptor protein that modulates T cell receptor (TCR)-induced signaling. SAP-deficient T cells exhibit impaired TCR restimulation-induced cell death (RICD) and diminished TCR-induced inhibition of diacylglycerol kinase α (DGKα), leading to increased diacylglycerol metabolism and decreased signaling through Ras and PKCθ (protein kinase Cθ). We show that down-regulation of DGKα activity in SAP-deficient T cells restores diacylglycerol signaling at the immune synapse and rescues RICD via induction of the proapoptotic proteins NUR77 and NOR1. Pharmacological inhibition of DGKα prevents the excessive CD8(+) T cell expansion and interferon-γ production that occur in SAP-deficient mice after lymphocytic choriomeningitis virus infection without impairing lytic activity. Collectively, these data highlight DGKα as a viable therapeutic target to reverse the life-threatening EBV-associated immunopathology that occurs in XLP-1 patients.
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Affiliation(s)
- Elisa Ruffo
- Department of Translational Medicine and Institute for Research and Cure of Autoimmune Diseases, University of Piemonte Orientale, 28100 Novara, Italy
| | - Valeria Malacarne
- Department of Translational Medicine and Institute for Research and Cure of Autoimmune Diseases, University of Piemonte Orientale, 28100 Novara, Italy
| | - Sasha E Larsen
- Department of Pharmacology and Molecular Therapeutics, Uniformed Services University of the Health Sciences, Bethesda, MD 20814, USA
| | - Rupali Das
- Department of Physiology, Michigan State University, East Lansing, MI 48824, USA
| | - Laura Patrussi
- Department of Life Sciences, University of Siena, 53100 Siena, Italy
| | - Christoph Wülfing
- School of Cellular and Molecular Medicine, University of Bristol, BS8 1TH Bristol, UK
| | - Christoph Biskup
- Biomolecular Photonics Group, Jena University Hospital, D 07740 Jena, Germany
| | - Senta M Kapnick
- Genetic Disease Research Branch, National Human Genome Research Institute, National Institutes of Health, Bethesda, MD 20892, USA
| | - Katherine Verbist
- Department of Oncology, St. Jude Children's Research Hospital, Memphis, TN 38105, USA
| | - Paige Tedrick
- Department of Oncology, St. Jude Children's Research Hospital, Memphis, TN 38105, USA
| | - Pamela L Schwartzberg
- Genetic Disease Research Branch, National Human Genome Research Institute, National Institutes of Health, Bethesda, MD 20892, USA
| | - Cosima T Baldari
- Department of Life Sciences, University of Siena, 53100 Siena, Italy
| | - Ignacio Rubio
- Integrated Research and Treatment Center, Center for Sepsis Control and Care and Institute of Molecular Cell Biology, Center for Molecular Biomedicine, Jena University Hospital, D-07745 Jena, Germany
| | - Kim E Nichols
- Department of Oncology, St. Jude Children's Research Hospital, Memphis, TN 38105, USA
| | - Andrew L Snow
- Department of Pharmacology and Molecular Therapeutics, Uniformed Services University of the Health Sciences, Bethesda, MD 20814, USA
| | - Gianluca Baldanzi
- Department of Translational Medicine and Institute for Research and Cure of Autoimmune Diseases, University of Piemonte Orientale, 28100 Novara, Italy
| | - Andrea Graziani
- Department of Translational Medicine and Institute for Research and Cure of Autoimmune Diseases, University of Piemonte Orientale, 28100 Novara, Italy. School of Medicine, University Vita e Salute San Raffaele, 20132 Milan, Italy.
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13
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Belguise K, Cherradi S, Sarr A, Boissière F, Boulle N, Simony-Lafontaine J, Choesmel-Cadamuro V, Wang X, Chalbos D. PKCθ-induced phosphorylations control the ability of Fra-1 to stimulate gene expression and cancer cell migration. Cancer Lett 2016; 385:97-107. [PMID: 27816489 DOI: 10.1016/j.canlet.2016.10.038] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2016] [Revised: 10/20/2016] [Accepted: 10/25/2016] [Indexed: 02/01/2023]
Abstract
The AP-1 transcription factor Fra-1 is aberrantly expressed in a large number of cancers and plays crucial roles in cancer development and progression by stimulating the expression of genes involved in these processes. However, the control of Fra-1 transactivation ability is still unclear and here we hypothesized that PKCθ-induced phosphorylation could be necessary to obtain a fully active Fra-1 protein. Using MCF7 stable cells overexpressing equivalent levels of unphosphorylated Fra-1 or PKCθ-phosphorylated Fra-1, we showed that PKCθ-induced phosphorylation of Fra-1 was crucial for the stimulation of MMP1 and IL6 expression. Consistently, we found a significant positive correlation between PRKCQ (coding for PKCθ) and MMP1 mRNA expression levels in human breast cancer samples. PKCθ-induced phosphorylations, in part at T217 and T227 residues, strongly and specifically increased Fra-1 transcriptional activity through the stimulation of Fra-1 transactivation domain, without affecting JUN factors. More importantly, these phosphorylations were required for Fra-1-induced migration of breast cancer cells and phosphorylated Fra-1 expression was enriched at the invasion front of human breast tumors. Taken together, our findings indicate that PKCθ-induced phosphorylation could be important for the function of Fra-1 in cancer progression.
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Affiliation(s)
- Karine Belguise
- IRCM, Institut de Recherche en Cancérologie de Montpellier, Montpellier, F-34298, France; INSERM, U1194, Montpellier, F-34298, France; Université de Montpellier, Montpellier, F-34090, France; Institut de Cancérologie de Montpellier, Montpellier, F-34298, France.
| | - Sara Cherradi
- IRCM, Institut de Recherche en Cancérologie de Montpellier, Montpellier, F-34298, France; INSERM, U1194, Montpellier, F-34298, France; Université de Montpellier, Montpellier, F-34090, France; Institut de Cancérologie de Montpellier, Montpellier, F-34298, France
| | - Awa Sarr
- IRCM, Institut de Recherche en Cancérologie de Montpellier, Montpellier, F-34298, France; INSERM, U1194, Montpellier, F-34298, France; Université de Montpellier, Montpellier, F-34090, France; Institut de Cancérologie de Montpellier, Montpellier, F-34298, France
| | - Florence Boissière
- Unité de Recherche Translationnelle, Institut Régional du Cancer de Montpellier, Montpellier, F-34298, France
| | - Nathalie Boulle
- Département de Biopathologie, CHU Montpellier, Montpellier, F-34295, France
| | - Joëlle Simony-Lafontaine
- Unité de Recherche Translationnelle, Institut Régional du Cancer de Montpellier, Montpellier, F-34298, France
| | - Valérie Choesmel-Cadamuro
- LBCMCP, Centre de Biologie Intégrative (CBI), Université de Toulouse, CNRS, UPS, 31062, Toulouse, France
| | - Xiaobo Wang
- LBCMCP, Centre de Biologie Intégrative (CBI), Université de Toulouse, CNRS, UPS, 31062, Toulouse, France
| | - Dany Chalbos
- IRCM, Institut de Recherche en Cancérologie de Montpellier, Montpellier, F-34298, France; INSERM, U1194, Montpellier, F-34298, France; Université de Montpellier, Montpellier, F-34090, France; Institut de Cancérologie de Montpellier, Montpellier, F-34298, France.
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14
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Blewett MM, Xie J, Zaro BW, Backus KM, Altman A, Teijaro JR, Cravatt BF. Chemical proteomic map of dimethyl fumarate-sensitive cysteines in primary human T cells. Sci Signal 2016; 9:rs10. [PMID: 27625306 DOI: 10.1126/scisignal.aaf7694] [Citation(s) in RCA: 128] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Dimethyl fumarate (DMF) is an electrophilic drug that is used to treat autoimmune conditions, including multiple sclerosis and psoriasis. The mechanism of action of DMF is unclear but may involve the covalent modification of proteins or DMF serving as a prodrug that is converted to monomethyl fumarate (MMF). We found that DMF, but not MMF, blocked the activation of primary human and mouse T cells. Using a quantitative, site-specific chemical proteomic platform, we determined the DMF sensitivity of >2400 cysteine residues in human T cells. Cysteines sensitive to DMF, but not MMF, were identified in several proteins with established biochemical or genetic links to T cell function, including protein kinase Cθ (PKCθ). DMF blocked the association of PKCθ with the costimulatory receptor CD28 by perturbing a CXXC motif in the C2 domain of this kinase. Mutation of these DMF-sensitive cysteines also impaired PKCθ-CD28 interactions and T cell activation, designating the C2 domain of PKCθ as a key functional, electrophile-sensing module important for T cell biology.
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Affiliation(s)
- Megan M Blewett
- Department of Chemical Physiology and The Skaggs Institute for Chemical Biology, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, CA 92037, USA
| | - Jiji Xie
- Division of Cell Biology, La Jolla Institute for Allergy and Immunology, 9420 Athena Circle, La Jolla, CA 92037, USA
| | - Balyn W Zaro
- Department of Chemical Physiology and The Skaggs Institute for Chemical Biology, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, CA 92037, USA
| | - Keriann M Backus
- Department of Chemical Physiology and The Skaggs Institute for Chemical Biology, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, CA 92037, USA
| | - Amnon Altman
- Division of Cell Biology, La Jolla Institute for Allergy and Immunology, 9420 Athena Circle, La Jolla, CA 92037, USA
| | - John R Teijaro
- Department of Chemical Physiology and The Skaggs Institute for Chemical Biology, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, CA 92037, USA. Department of Immunology and Microbial Science, The Scripps Research Institute, La Jolla, CA 92037, USA.
| | - Benjamin F Cravatt
- Department of Chemical Physiology and The Skaggs Institute for Chemical Biology, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, CA 92037, USA.
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15
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Finley J. Oocyte activation and latent HIV-1 reactivation: AMPK as a common mechanism of action linking the beginnings of life and the potential eradication of HIV-1. Med Hypotheses 2016; 93:34-47. [PMID: 27372854 DOI: 10.1016/j.mehy.2016.05.012] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2015] [Accepted: 05/12/2016] [Indexed: 01/22/2023]
Abstract
In all mammalian species studied to date, the initiation of oocyte activation is orchestrated through alterations in intracellular calcium (Ca(2+)) signaling. Upon sperm binding to the oocyte plasma membrane, a sperm-associated phospholipase C (PLC) isoform, PLC zeta (PLCζ), is released into the oocyte cytoplasm. PLCζ hydrolyzes phosphatidylinositol 4,5-bisphosphate (PIP2) to produce diacylglycerol (DAG), which activates protein kinase C (PKC), and inositol 1,4,5-trisphosphate (IP3), which induces the release of Ca(2+) from endoplasmic reticulum (ER) Ca(2+) stores. Subsequent Ca(2+) oscillations are generated that drive oocyte activation to completion. Ca(2+) ionophores such as ionomycin have been successfully used to induce artificial human oocyte activation, facilitating fertilization during intra-cytoplasmic sperm injection (ICSI) procedures. Early studies have also demonstrated that the PKC activator phorbol 12-myristate 13-acetate (PMA) acts synergistically with Ca(2+) ionophores to induce parthenogenetic activation of mouse oocytes. Interestingly, the Ca(2+)-induced signaling cascade characterizing sperm or chemically-induced oocyte activation, i.e. the "shock and live" approach, bears a striking resemblance to the reactivation of latently infected HIV-1 viral reservoirs via the so called "shock and kill" approach, a method currently being pursued to eradicate HIV-1 from infected individuals. PMA and ionomycin combined, used as positive controls in HIV-1 latency reversal studies, have been shown to be extremely efficient in reactivating latent HIV-1 in CD4(+) memory T cells by inducing T cell activation. Similar to oocyte activation, T cell activation by PMA and ionomycin induces an increase in intracellular Ca(2+) concentrations and activation of DAG, PKC, and downstream Ca(2+)-dependent signaling pathways necessary for proviral transcription. Interestingly, AMPK, a master regulator of cell metabolism that is activated thorough the induction of cellular stress (e.g. increase in Ca(2+) concentration, reactive oxygen species generation, increase in AMP/ATP ratio) is essential for oocyte maturation, T cell activation, and mitochondrial function. In addition to the AMPK kinase LKB1, CaMKK2, a Ca(2+)/calmodulin-dependent kinase that also activates AMPK, is present in and activated on T cell activation and is also present in mouse oocytes and persists until the zygote and two-cell stages. It is our hypothesis that AMPK activation represents a central node linking T cell activation-induced latent HIV-1 reactivation and both physiological and artificial oocyte activation. We further propose the novel observation that various compounds that have been shown to reactivate latent HIV-1 (e.g. PMA, ionomycin, metformin, bryostatin, resveratrol, etc.) or activate oocytes (PMA, ionomycin, ethanol, puromycin, etc.) either alone or in combination likely do so via stress-induced activation of AMPK.
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16
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Finley J. Reactivation of latently infected HIV-1 viral reservoirs and correction of aberrant alternative splicing in the LMNA gene via AMPK activation: Common mechanism of action linking HIV-1 latency and Hutchinson–Gilford progeria syndrome. Med Hypotheses 2015; 85:320-32. [DOI: 10.1016/j.mehy.2015.06.003] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2015] [Revised: 05/25/2015] [Accepted: 06/08/2015] [Indexed: 12/30/2022]
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17
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Abstract
The protein kinases C (PKCs) are a family of serine/threonine kinases involved in regulating multiple essential cellular processes such as survival, proliferation, and differentiation. Of particular interest is the novel, calcium-independent PKCθ which plays a central role in immune responses. PKCθ shares structural similarities with other PKC family members, mainly consisting of an N-terminal regulatory domain and a C-terminal catalytic domain tethered by a hinge region. This isozyme, however, is unique in that it translocates to the immunological synapse between a T cell and an antigen-presenting cell (APC) upon T cell receptor-peptide MHC recognition. Thereafter, PKCθ interacts physically and functionally with downstream effectors to mediate T cell activation and differentiation, subsequently leading to inflammation. PKCθ-specific perturbations have been identified in several diseases, most notably autoimmune disorders, and hence the modulation of its activity presents an attractive therapeutic intervention. To that end, many inhibitors of PKCs and PKCθ have been developed and tested in preclinical and clinical studies. And although selectivity remains a challenge, results are promising for the future development of effective PKCθ inhibitors that would greatly advance the treatment of several T-cell mediated diseases.
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18
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Sutcliffe EL, Rao S. Duplicity of protein kinase C-θ: Novel insights into human T-cell biology. Transcription 2014; 2:189-192. [PMID: 21922062 DOI: 10.4161/trns.2.4.16565] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2011] [Revised: 06/16/2011] [Accepted: 06/21/2011] [Indexed: 01/13/2023] Open
Abstract
We recently reported on a new wrinkle of complexity in how eukaryotic genes are regulated by providing evidence for a hitherto unknown nuclear function of the signaling kinase, Protein Kinase C-theta (PKC-θ). This chromatin-anchored complex positively regulates inducible immune genes and negatively regulates target miRNA genes. These data challenge the traditional view of mammalian signaling kinases and provides new avenues for therapeutic drug design.
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Affiliation(s)
- Elissa L Sutcliffe
- Discipline of Biomedical Sciences; Faculty of Applied Science; University of Canberra; Canberra, Australia
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19
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Leung CS, Yeung TL, Yip KP, Pradeep S, Balasubramanian L, Liu J, Wong KK, Mangala LS, Armaiz-Pena GN, Lopez-Berestein G, Sood AK, Birrer MJ, Mok SC. Calcium-dependent FAK/CREB/TNNC1 signalling mediates the effect of stromal MFAP5 on ovarian cancer metastatic potential. Nat Commun 2014; 5:5092. [PMID: 25277212 PMCID: PMC4185407 DOI: 10.1038/ncomms6092] [Citation(s) in RCA: 94] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2014] [Accepted: 08/28/2014] [Indexed: 12/13/2022] Open
Abstract
Ovarian cancer is the most lethal gynaecologic malignancy in the United States, and advanced serous ovarian adenocarcinoma is responsible for most ovarian cancer deaths. However, the stroma-derived molecular determinants that modulate patient survival are yet to be characterized. Here we identify a stromal gene signature for advanced high-grade serous ovarian cancer using microdissected stromal ovarian tumour samples and find that stromal microfibrillar-associated protein 5 (MFAP5) is a prognostic marker for poor survival. Further functional studies reveal that FAK/CREB/TNNC1 signalling pathways mediate the effect of MFAP5 on ovarian cancer cell motility and invasion potential. Targeting stromal MFAP5 using MFAP5-specific siRNA encapsulated in chitosan nanoparticles significantly decreases ovarian tumour growth and metastasis in vivo, suggesting that it may be a new modality of ovarian cancer treatment.
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Affiliation(s)
- Cecilia S. Leung
- Department of Gynecologic Oncology and Reproductive Medicine, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA
- The University of Texas Graduate School of Biomedical Sciences at Houston, Houston, TX 77030, USA
| | - Tsz-Lun Yeung
- Department of Gynecologic Oncology and Reproductive Medicine, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA
| | - Kay-Pong Yip
- Department of Molecular Pharmacology and Physiology, University of South Florida, Tampa, FL 33612, USA
| | - Sunila Pradeep
- Department of Gynecologic Oncology and Reproductive Medicine, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA
| | - Lavanya Balasubramanian
- Department of Molecular Pharmacology and Physiology, University of South Florida, Tampa, FL 33612, USA
| | - Jinsong Liu
- Department of Pathology, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA
| | - Kwong-Kwok Wong
- Department of Gynecologic Oncology and Reproductive Medicine, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA
- The University of Texas Graduate School of Biomedical Sciences at Houston, Houston, TX 77030, USA
| | - Lingegowda S. Mangala
- Department of Gynecologic Oncology and Reproductive Medicine, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA
- The Center for RNA Interference and Non-Coding RNAs, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA
| | - Guillermo N. Armaiz-Pena
- Department of Gynecologic Oncology and Reproductive Medicine, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA
| | - Gabriel Lopez-Berestein
- Department of Cancer Biology, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA
- The Center for RNA Interference and Non-Coding RNAs, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA
- Department of Experimental Therapeutics, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA
| | - Anil K. Sood
- Department of Gynecologic Oncology and Reproductive Medicine, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA
- The University of Texas Graduate School of Biomedical Sciences at Houston, Houston, TX 77030, USA
- Department of Cancer Biology, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA
- The Center for RNA Interference and Non-Coding RNAs, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA
| | - Michael J. Birrer
- Department of Medicine, Massachusetts General Hospital, Harvard Medical School, Boston, MA 02114, USA
| | - Samuel C. Mok
- Department of Gynecologic Oncology and Reproductive Medicine, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA
- The University of Texas Graduate School of Biomedical Sciences at Houston, Houston, TX 77030, USA
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Kikuchi H, Nakayama M, Kuribayashi F, Imajoh-Ohmi S, Nishitoh H, Takami Y, Nakayama T. Protein kinase Cθ gene expression is oppositely regulated by GCN5 and EBF1 in immature B cells. FEBS Lett 2014; 588:1739-42. [PMID: 24657615 DOI: 10.1016/j.febslet.2014.03.025] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2014] [Revised: 03/11/2014] [Accepted: 03/12/2014] [Indexed: 01/11/2023]
Abstract
In this study, we revealed that GCN5 and early B cell factor 1 (EBF1) participate in regulation of protein kinase Cθ (PKCθ) gene expression in an opposite manner in immature B cells. GCN5-deficiency in DT40 caused drastic down-regulation of transcription of PKCθ. In contrast, EBF1-deficiency brought about remarkable up-regulation of that of PKCθ, and re-expression of EBF1 dramatically suppressed transcription of PKCθ. Chromatin immunoprecipitation assay revealed that GCN5 binds to the 5'-flanking region of the chicken PKCθ gene and acetylates histone H3, and EBF1 binds to the 5'-flanking region of the gene surrounding putative EBF1 binding motifs.
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Affiliation(s)
- Hidehiko Kikuchi
- Section of Biochemistry and Molecular Biology, Department of Medical Sciences, Faculty of Medicine, University of Miyazaki, 5200, Kihara, Kiyotake, Miyazaki 889-1692, Japan; Laboratory Center for Proteomics Research, Graduate School of Frontier Sciences, The Institute of Medical Science, The University of Tokyo, 4-6-1 Shirokanedai, Tokyo 108-8639, Japan.
| | - Masami Nakayama
- Section of Biochemistry and Molecular Biology, Department of Medical Sciences, Faculty of Medicine, University of Miyazaki, 5200, Kihara, Kiyotake, Miyazaki 889-1692, Japan
| | - Futoshi Kuribayashi
- Laboratory Center for Proteomics Research, Graduate School of Frontier Sciences, The Institute of Medical Science, The University of Tokyo, 4-6-1 Shirokanedai, Tokyo 108-8639, Japan; Department of Biochemistry, Kawasaki Medical School, 577, Matsushima, Kurashiki, Okayama 701-0192, Japan
| | - Shinobu Imajoh-Ohmi
- Laboratory Center for Proteomics Research, Graduate School of Frontier Sciences, The Institute of Medical Science, The University of Tokyo, 4-6-1 Shirokanedai, Tokyo 108-8639, Japan
| | - Hideki Nishitoh
- Section of Biochemistry and Molecular Biology, Department of Medical Sciences, Faculty of Medicine, University of Miyazaki, 5200, Kihara, Kiyotake, Miyazaki 889-1692, Japan
| | - Yasunari Takami
- Section of Biochemistry and Molecular Biology, Department of Medical Sciences, Faculty of Medicine, University of Miyazaki, 5200, Kihara, Kiyotake, Miyazaki 889-1692, Japan
| | - Tatsuo Nakayama
- Section of Biochemistry and Molecular Biology, Department of Medical Sciences, Faculty of Medicine, University of Miyazaki, 5200, Kihara, Kiyotake, Miyazaki 889-1692, Japan
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Kwon MS, Park KR, Kim YD, Na BR, Kim HR, Choi HJ, Piragyte I, Jeon H, Chung KH, Song WK, Eom SH, Jun CD. Swiprosin-1 is a novel actin bundling protein that regulates cell spreading and migration. PLoS One 2013; 8:e71626. [PMID: 23977092 PMCID: PMC3744483 DOI: 10.1371/journal.pone.0071626] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2013] [Accepted: 06/28/2013] [Indexed: 11/18/2022] Open
Abstract
Protein functions are often revealed by their localization to specialized cellular sites. Recent reports demonstrated that swiprosin-1 is found together with actin and actin-binding proteins in the cytoskeleton fraction of human mast cells and NK-like cells. However, direct evidence of whether swiprosin-1 regulates actin dynamics is currently lacking. We found that swiprosin-1 localizes to microvilli-like membrane protrusions and lamellipodia and exhibits actin-binding activity. Overexpression of swiprosin-1 enhanced lamellipodia formation and cell spreading. In contrast, swiprosin-1 knockdown showed reduced cell spreading and migration. Swiprosin-1 induced actin bundling in the presence of Ca(2+), and deletion of the EF-hand motifs partially reduced bundling activity. Swiprosin-1 dimerized in the presence of Ca(2+) via its coiled-coil domain, and a lysine (Lys)-rich region in the coiled-coil domain was essential for regulation of actin bundling. Consistent with these observations, mutations of the EF-hand motifs and coiled-coil region significantly reduced cell spreading and lamellipodia formation. We provide new evidence of how swiprosin-1 influences cytoskeleton reorganization and cell spreading.
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Affiliation(s)
- Min-Sung Kwon
- School of Life Sciences, Immune Synapse Research Center and Cell Dynamics Research Center, Gwangju Institute of Science and Technology, Gwangju, Korea
| | - Kyoung Ryoung Park
- School of Life Sciences, Immune Synapse Research Center and Cell Dynamics Research Center, Gwangju Institute of Science and Technology, Gwangju, Korea
| | - Young-Dae Kim
- School of Life Sciences, Immune Synapse Research Center and Cell Dynamics Research Center, Gwangju Institute of Science and Technology, Gwangju, Korea
| | - Bo-Ra Na
- School of Life Sciences, Immune Synapse Research Center and Cell Dynamics Research Center, Gwangju Institute of Science and Technology, Gwangju, Korea
| | - Hye-Ran Kim
- School of Life Sciences, Immune Synapse Research Center and Cell Dynamics Research Center, Gwangju Institute of Science and Technology, Gwangju, Korea
| | - Hak-Jong Choi
- School of Life Sciences, Immune Synapse Research Center and Cell Dynamics Research Center, Gwangju Institute of Science and Technology, Gwangju, Korea
| | - Indre Piragyte
- School of Life Sciences, Immune Synapse Research Center and Cell Dynamics Research Center, Gwangju Institute of Science and Technology, Gwangju, Korea
| | - Hyesung Jeon
- Biomedical Research Center, Korea Institute of Science and Technology, Seongbuk-gu, Seoul, Korea
| | - Kyung Hwun Chung
- School of Life Sciences, Immune Synapse Research Center and Cell Dynamics Research Center, Gwangju Institute of Science and Technology, Gwangju, Korea
| | - Woo Keun Song
- School of Life Sciences, Immune Synapse Research Center and Cell Dynamics Research Center, Gwangju Institute of Science and Technology, Gwangju, Korea
| | - Soo Hyun Eom
- School of Life Sciences, Immune Synapse Research Center and Cell Dynamics Research Center, Gwangju Institute of Science and Technology, Gwangju, Korea
| | - Chang-Duk Jun
- School of Life Sciences, Immune Synapse Research Center and Cell Dynamics Research Center, Gwangju Institute of Science and Technology, Gwangju, Korea
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Na BR, Kim HR, Kwon MS, Lee HS, Piragyte I, Choi EJ, Choi HK, Han WC, Lee SH, Jun CD. Aplotaxene blocks T cell activation by modulation of protein kinase C-θ-dependent pathway. Food Chem Toxicol 2013; 62:23-31. [PMID: 23941771 DOI: 10.1016/j.fct.2013.08.016] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2013] [Revised: 07/15/2013] [Accepted: 08/07/2013] [Indexed: 12/12/2022]
Abstract
Aplotaxene, (8Z, 11Z, 14Z)-heptadeca-1, 8, 11, 14-tetraene, is one of the major components of essential oil obtained from Inula helenium root, which is used in Oriental medicine. However, the effects of aplotaxene on immunity have not been investigated. Here, we show that aplotaxene inhibits T cell activation in terms of IL-2 and CD69 expression. Aplotaxene, at a concentration that optimally inhibits IL-2 production, has little effect on apoptotic or necrotic cell death, suggesting that apoptosis is not a mechanism for aplotaxene-mediated inhibition of T cell activation. Aplotaxene affects neither superantigeninduced conjugate formation between Jurkat T cells and Raji B cells nor clustering of CD3 and LFA-1 at the immunological synapse. Aplotaxene significantly inhibits PKC-θ phosphorylation and translocation to the immunological synapse, and blocks PMA-induced T-cell receptor internalization. Furthermore, aplotaxene leads to inhibition of mitogen-activated protein kinases (JNK, ERK and p38) phosphorylation and NF-κB, NF-AT, and AP-1 promoter activities in Jurkat T cells. Taken together, our findings provide evidence for the immunosuppressive effect of aplotaxene on activated T cells through the modulation of the PKC-θ and MAPK pathways, suggesting that aplotaxene may be a novel immunotherapeutic agent for immunological diseases related to the overactivation of T cells.
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Affiliation(s)
- Bo-Ra Na
- School of Life Sciences, Immune Synapse Research Center and Cell Dynamics Research Center, Gwangju Institute of Science and Technology, Gwangju 500-712, Republic of Korea
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23
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Schmitt AC, Popp AC, Cohen C, Lawson D, Siddiqui MT. Differential Expression of Two Different DOG-1 Antibodies: Utility in Detecting Gastrointestinal Stromal Tumors. J Histotechnol 2013. [DOI: 10.1179/his.2010.33.2.71] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022]
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Inhibitors of switch kinase 'spleen tyrosine kinase' in inflammation and immune-mediated disorders: a review. Eur J Med Chem 2013; 67:434-46. [PMID: 23917087 DOI: 10.1016/j.ejmech.2013.04.070] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2013] [Revised: 04/17/2013] [Accepted: 04/18/2013] [Indexed: 12/29/2022]
Abstract
Spleen tyrosine kinase (Syk), a member of Syk family of non-receptor protein tyrosine kinases plays a significant role in the immune cell signaling in B cells, mast cells, macrophages and neutrophils. Anomalous regulation of this kinase can lead to different allergic disorders and antibody-mediated autoimmune diseases such as rheumatoid arthritis, asthma, psoriasis and allergic rhinitis. Being involved in the growth and survive mechanism of B cells, its inhibition can be beneficial in B-cell lymphoma. Thus, Syk can be sited as a therapeutically relevant target for various allergic and autoimmune disorders. This review article describes the structure of Syk and its role in B-cell signaling. In addition to this, data regarding small molecule inhibitors of Syk has also been reviewed from different papers and patents published.
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Abstract
The molecular biology revolution coupled with the development of monoclonal antibody technology enabled remarkable progress in rheumatology therapy, comprising an array of highly effective biologic agents. With advances in understanding of the molecular nature of immune cell receptors came elucidation of intracellular signalling pathways downstream of these receptors. These discoveries raise the question of whether selective targeting of key intracellular factors with small molecules would add to the rheumatologic armamentarium. In this Review, we discuss several examples of this therapeutic strategy that seem to be successful, and consider their implications for the future of immune-targeted treatments. We focus on kinase inhibitors, primarily those targeting Janus kinase family members and spleen tyrosine kinase, given their advanced status in clinical development and application. We also summarize other targets involved in signalling pathways that might offer promise for therapeutic intervention in the future.
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26
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Protein kinase antagonists as therapeutic agents for immunological and inflammatory disorders. Clin Immunol 2013. [DOI: 10.1016/b978-0-7234-3691-1.00102-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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27
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Michalczyk I, Sikorski AF, Kotula L, Junghans RP, Dubielecka PM. The emerging role of protein kinase Cθ in cytoskeletal signaling. J Leukoc Biol 2012. [PMID: 23192428 DOI: 10.1189/jlb.0812371] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Cytoskeletal rearrangements often occur as the result of transduction of signals from the extracellular environment. Efficient awakening of this powerful machinery requires multiple activation and deactivation steps, which usually involve phosphorylation or dephosphorylation of different signaling units by kinases and phosphatases, respectively. In this review, we discuss the signaling characteristics of one of the nPKC isoforms, PKCθ, focusing on PKCθ-mediated signal transduction to cytoskeletal elements, which results in cellular rearrangements critical for cell type-specific responses to stimuli. PKCθ is the major PKC isoform present in hematopoietic and skeletal muscle cells. PKCθ plays roles in T cell signaling through the IS, survival responses in adult T cells, and T cell FasL-mediated apoptosis, all of which involve cytoskeletal rearrangements and relocation of this enzyme. PKCθ has been linked to the regulation of cell migration, lymphoid cell motility, and insulin signaling and resistance in skeletal muscle cells. Additional roles were suggested for PKCθ in mitosis and cell-cycle regulation. Comprehensive understanding of cytoskeletal regulation and the cellular "modus operandi" of PKCθ holds promise for improving current therapeutic applications aimed at autoimmune diseases.
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Affiliation(s)
- Izabela Michalczyk
- Laboratory of Cytobiochemistry, Faculty of Biotechnology, University of Wroclaw, Wroclaw, Poland
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Merino E, Abeyweera TP, Firth MA, Zawislak CL, Basu R, Liu X, Sun JC, Huse M. Protein Kinase C-θ Clustering at Immunological Synapses Amplifies Effector Responses in NK Cells. THE JOURNAL OF IMMUNOLOGY 2012; 189:4859-69. [DOI: 10.4049/jimmunol.1200825] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
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Takahashi RH, Matsubayashi J, Yokotsuka M, Tachibana M, Kusama H, Nagao T. An intrapelvic extraintestinal gastrointestinal stromal tumor of undetermined origin: diagnosis by prostate needle biopsy. Pathol Res Pract 2012; 208:736-40. [PMID: 23057997 DOI: 10.1016/j.prp.2012.09.003] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/28/2012] [Revised: 07/30/2012] [Accepted: 09/04/2012] [Indexed: 12/19/2022]
Abstract
We herein report a case of intrapelvic gastrointestinal stromal tumor (GIST) of undetermined origin in a 48-year-old male who presented with dysuria. An enlarged tumor was detected on digital rectal examination. Imaging studies showed a solid and lobular homogenous tumor of 7.0 cm in diameter. The tumor was attached to the right dorsal aspect of the prostate with compression of the seminal vesicles and rectum. It was considered that the tumor had arisen from the prostate, although the patient's serum prostate-specific antigen level was low (0.436 ng/mL). The histological diagnosis by prostate needle biopsy was a spindle cell tumor. At cystoprostatectomy, the tumor was confirmed to be separated from the prostate by a fibrous band, and showed spindle cells with a fascicular growth pattern, but without necrotic areas. Mitotic figures were noted in 12 of 50 high-power fields. The tumor cells were immunoreactive for the KIT protein (CD117), CD34, Discovered on GIST-1 (DOG-1), and vimentin. In contrast, they were negative for desmin, α-smooth muscle actin, pancytokeratin (AE1/AE3), and S100 protein. The Ki-67 labeling index was 5%. The genetic analyses targeting the c-kit gene revealed a point mutation at codon 559 (GTT→GAT). The diagnosis of GIST was confirmed on the basis of the morphological features, immunoprofile, and results of the molecular analyses. Since extraintestinal GIST can resemble a prostatic tumor clinically, KIT (CD117) and DOG-1 should be considered for inclusion in the immunohistochemical panel for spindle cell tumors obtained by prostate needle biopsy.
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Kaur M, Bahia MS, Silakari O. Inhibitors of interleukin-2 inducible T-cell kinase as potential therapeutic candidates for the treatment of various inflammatory disease conditions. Eur J Pharm Sci 2012; 47:574-88. [PMID: 22820564 DOI: 10.1016/j.ejps.2012.07.013] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2012] [Revised: 07/05/2012] [Accepted: 07/05/2012] [Indexed: 12/19/2022]
Abstract
Interleukin-2 inducible T-cell kinase (ITK), a member of Tec family of non-receptor protein tyrosine kinases plays a domineering role in the T-cell development, differentiation and production of pro-inflammatory cytokines such as IL-2, IL-4, IL-5, IL-10, IL-13 and IL-17. This kinase is also an important contributor in Th 2 cells mediated autoimmune and allergic disease conditions, e.g. psoriasis, atopic dermatitis and allergic asthma. ITK modulates T-cell signaling by activating PLCγ1 and regulating the extent of Ca²⁺ flux. It contributes in prolific T-cell responses by maintaining cellular adhesion and cytoskeleton reorganization via actin polymerization and integrin binding. This review article describes the structure of ITK and its role in T-cell signaling. In addition to this, data regarding small molecule inhibitors of ITK has also been reviewed from different papers and patents published.
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Affiliation(s)
- Maninder Kaur
- Molecular Modeling Lab-MML, Department of Pharmaceutical Sciences and Drug Research, Punjabi University, Patiala, Punjab 147002, India
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31
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Baldanzi G, Pighini A, Bettio V, Rainero E, Traini S, Chianale F, Porporato PE, Filigheddu N, Mesturini R, Song S, Schweighoffer T, Patrussi L, Baldari CT, Zhong XP, van Blitterswijk WJ, Sinigaglia F, Nichols KE, Rubio I, Parolini O, Graziani A. SAP-mediated inhibition of diacylglycerol kinase α regulates TCR-induced diacylglycerol signaling. THE JOURNAL OF IMMUNOLOGY 2011; 187:5941-51. [PMID: 22048771 DOI: 10.4049/jimmunol.1002476] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Diacylglycerol kinases (DGKs) metabolize diacylglycerol to phosphatidic acid. In T lymphocytes, DGKα acts as a negative regulator of TCR signaling by decreasing diacylglycerol levels and inducing anergy. In this study, we show that upon costimulation of the TCR with CD28 or signaling lymphocyte activation molecule (SLAM), DGKα, but not DGKζ, exits from the nucleus and undergoes rapid negative regulation of its enzymatic activity. Inhibition of DGKα is dependent on the expression of SAP, an adaptor protein mutated in X-linked lymphoproliferative disease, which is essential for SLAM-mediated signaling and contributes to TCR/CD28-induced signaling and T cell activation. Accordingly, overexpression of SAP is sufficient to inhibit DGKα, whereas SAP mutants unable to bind either phospho-tyrosine residues or SH3 domain are ineffective. Moreover, phospholipase C activity and calcium, but not Src-family tyrosine kinases, are also required for negative regulation of DGKα. Finally, inhibition of DGKα in SAP-deficient cells partially rescues defective TCR/CD28 signaling, including Ras and ERK1/2 activation, protein kinase C membrane recruitment, induction of NF-AT transcriptional activity, and IL-2 production. Thus SAP-mediated inhibition of DGKα sustains diacylglycerol signaling, thereby regulating T cell activation, and it may represent a novel pharmacological strategy for X-linked lymphoproliferative disease treatment.
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Affiliation(s)
- Gianluca Baldanzi
- Department of Clinical and Experimental Medicine, University A. Avogadro of Piemonte Orientale, 28100 Novara, Italy.
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High nuclear protein kinase Cθ expression may correlate with disease recurrence and poor survival in oral squamous cell carcinoma. Hum Pathol 2011; 43:276-81. [PMID: 21840039 DOI: 10.1016/j.humpath.2011.05.001] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/24/2011] [Revised: 05/02/2011] [Accepted: 05/04/2011] [Indexed: 11/22/2022]
Abstract
Protein kinase Cs play important roles in many biological processes and tumorigenesis. This study examined the expression of protein kinase Cθ and assessed its significance in patients with oral squamous cell carcinoma. Immunohistochemical staining was carried out to investigate the expression of protein kinase Cθ in 59 cases of oral squamous cell carcinoma. The results were correlated with clinical characteristics and outcome of patients. Diffuse cytoplasmic protein kinase Cθ was identified in 53 (89.8%) of the 59 oral squamous cell carcinoma cases, and the expression was not statistically associated with any clinicopathologic parameter. Twenty (40.7%) of the 59 oral squamous cell carcinoma cases exhibited nuclear expression of protein kinase Cθ with different grade of intensity. χ(2) analysis indicated that high nuclear protein kinase Cθ expression correlated significantly with shorter 24-month survival (P = .043) and disease recurrence (P = .019). The Kaplan-Meier method also showed that high nuclear expression of protein kinase Cθ was significantly associated with poor overall survival (P = .034) and shorter time to recurrence (P = .003). Univariate analysis revealed that high nuclear protein kinase Cθ expression (P = .046; hazard ratio, 2.2), tumor size less than 2 cm (P = .049; hazard ratio, 4.7), lymph node metastasis (P = .003; hazard ratio, 3.0), and higher stage (P = .002; hazard ratio, 8.7) were each associated with shorter overall survival. We identified the aberrant nuclear expression of protein kinase Cθ in oral squamous cell carcinoma. High nuclear protein kinase Cθ expression may correlate with disease recurrence and poor survival in patients with oral squamous cell carcinoma.
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Huse M. Lymphocyte polarity, the immunological synapse and the scope of biological analogy. BIOARCHITECTURE 2011; 1:180-185. [PMID: 22069511 DOI: 10.4161/bioa.1.4.17594] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/27/2011] [Accepted: 07/30/2011] [Indexed: 12/29/2022]
Abstract
Lymphocytes such as T cells, B cells and natural killer (NK) cells form specialized contacts, called immunological synapses, with other cells in order to engage in specific intercellular communication and killing. Synapse formation is associated with the polarization of the microtubule-organizing center (MTOC) toward the contact site, which enables the directional secretion of cytokines and lytic factors. Although MTOC reorientation to the synapse is crucial for lymphocyte function, it has been difficult to study because of technical constraints. We have developed a photoactivation and imaging strategy that enables high-resolution analysis of cytoskeletal dynamics in individual T cells. Using this approach, we have demonstrated that the lipid second messenger diacylglycerol plays a crucial role in promoting MTOC reorientation by recruiting three members of the protein kinase C family to the synapse. Here, I will discuss these results along with studies from other labs, which have explored the role of polarity-inducing protein complexes after synapse formation. I will also propose a two-step model for MTOC reorientation in lymphocytes that reflects what we now know about the subject. Finally, I will consider the extent to which lymphocyte polarity resembles analogous cell polarity systems in other cell types.
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Affiliation(s)
- Morgan Huse
- Immunology Program; Memorial Sloan-Kettering Cancer Center; New York, NY USA
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A cascade of protein kinase C isozymes promotes cytoskeletal polarization in T cells. Nat Immunol 2011; 12:647-54. [PMID: 21602810 DOI: 10.1038/ni.2033] [Citation(s) in RCA: 122] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2010] [Accepted: 04/05/2011] [Indexed: 12/18/2022]
Abstract
Polarization of the T cell microtubule-organizing center (MTOC) toward the antigen-presenting cell (APC) is driven by the accumulation of diacylglycerol (DAG) at the immunological synapse (IS). The mechanisms that couple DAG to the MTOC are not known. By single-cell photoactivation of the T cell antigen receptor (TCR), we found that three distinct isoforms of protein kinase C (PKC) were recruited by DAG to the IS in two steps. PKC-ɛ and PKC-η accumulated first in a broad region of membrane, whereas PKC-θ arrived later in a smaller zone. Functional experiments indicated that PKC-θ was required for MTOC reorientation and that PKC-ɛ and PKC-η operated redundantly to promote the recruitment of PKC-θ and subsequent polarization responses. Our results establish a previously uncharacterized role for PKC proteins in T cell polarity.
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Itk: the rheostat of the T cell response. JOURNAL OF SIGNAL TRANSDUCTION 2011; 2011:297868. [PMID: 21747996 PMCID: PMC3116522 DOI: 10.1155/2011/297868] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/02/2010] [Accepted: 01/19/2011] [Indexed: 12/28/2022]
Abstract
The nonreceptor tyrosine kinase Itk plays a key role in TCR-initiated signaling that directly and significantly affects the regulation of PLCγ1 and the consequent mobilization of Ca2+. Itk also participates in the regulation of cytoskeletal reorganization as well as cellular adhesion, which is necessary for a productive T cell response. The functional cellular outcome of these molecular regulations by Itk renders it an important mediator of T cell development and differentiation. This paper encompasses the structure of Itk, the signaling parameters leading to Itk activation, and Itk effects on molecular pathways resulting in functional cellular outcomes. The incorporation of these factors persuades one to believe that Itk serves as a modulator, or rheostat, critically fine-tuning the T cell response.
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Fatima N, Cohen C, Siddiqui MT. DOG1 utility in diagnosing gastrointestinal stromal tumors on fine-needle aspiration. Cancer Cytopathol 2011; 119:202-8. [DOI: 10.1002/cncy.20149] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2010] [Revised: 01/17/2011] [Accepted: 01/27/2011] [Indexed: 11/07/2022]
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Wong NACS, Shelley-Fraser G. Specificity of DOG1 (K9 clone) and protein kinase C theta (clone 27) as immunohistochemical markers of gastrointestinal stromal tumour. Histopathology 2010; 57:250-8. [PMID: 20716167 DOI: 10.1111/j.1365-2559.2010.03622.x] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
AIMS DOG1 and protein kinase C (PKC) theta are both sensitive immunohistochemical markers of gastrointestinal stromal tumour (GIST). However, there are conflicting data regarding the specificity of the most commonly used PKC theta antibody (clone 27), and there are no existing data regarding the specificity of the only known commercially available DOG1 antibody (K9 clone) at the time of writing. This study's aim was to characterize the immunoreactivity patterns of both monoclonal antibodies amongst a wide range of neoplasm types including, in particular, histological mimics of GIST. METHODS AND RESULTS Immunohistochemistry for DOG1 and PKC theta was performed on whole tissue sections from 23 different neoplasm types (total of 125 cases). Ten of these neoplasm types showed CD117 immunopositivity. Only three (Ewing's sarcoma, glomus tumour and synovial sarcoma) of the 23 neoplasm types showed DOG1 immunopositivity, and such positivity was often focal and weak in intensity. In contrast, all but four (ganglioneuromas, leiomyomas, desmoplastic small round cell tumours and PEComa/angiomyolipomas) of the 23 neoplasm types showed PKC theta immunopositivity. CONCLUSIONS Compared with CD117, DOG1 (using the K9 antibody) is a more specific marker, whereas PKC theta (using the clone 27 antibody) is a considerably less specific immunohistochemical marker for GIST.
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Affiliation(s)
- Newton A C S Wong
- Department of Histopathology, Bristol Royal Infirmary, Marlborough Street, Bristol, UK.
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Thompson J, Burger ML, Whang H, Winoto A. Protein kinase C regulates mitochondrial targeting of Nur77 and its family member Nor-1 in thymocytes undergoing apoptosis. Eur J Immunol 2010; 40:2041-9. [PMID: 20411565 DOI: 10.1002/eji.200940231] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Nur77 orphan steroid receptor and its family member Nor-1 are required for apoptosis of developing T cells. In thymocytes, signals from the TCR complex induce Nur77 and Nor-1 expression followed by translocation from the nucleus to mitochondria. Nur77 and Nor-1 associate with Bcl-2 in the mitochondria, resulting in a conformation change that exposes the Bcl-2 BH3 domain, a presumed pro-apoptotic molecule of Bcl-2. As Nur77 and Nor-1 are heavily phosphorylated, we examined the requirement of Nur77 and Nor-1 phosphorylation in mitochondria translocation and Bcl-2 BH3 exposure. We found that HK434, a PKC agonist, in combination with calcium ionophore, can induce Nur77 and Nor-1 phosphorylation, translocation, Bcl-2 BH3 exposure and thymocyte apoptosis. Inhibitors of both classical and novel forms of PKC were able to block this process. In contrast, only the general but not classical PKC-specific inhibitors were able to block the same process initiated by PMA, a commonly used PKC agonist. These data demonstrate a differential activation of PKC isoforms by PMA and HK434 in thymocytes, and show the importance of PKC in mitochondria translocation of Nur77/Nor-1 and Bcl-2 conformation change during TCR-induced thymocyte apoptosis.
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Affiliation(s)
- Jennifer Thompson
- Cancer Research Laboratory and Department of Molecular and Cell Biology, Division of Immunology and Pathogenesis, University of California, Berkeley, CA, USA
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39
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Yang L, Qiao G, Ying H, Zhang J, Yin F. TCR-induced Akt serine 473 phosphorylation is regulated by protein kinase C-alpha. Biochem Biophys Res Commun 2010; 400:16-20. [PMID: 20691662 DOI: 10.1016/j.bbrc.2010.07.126] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2010] [Accepted: 07/30/2010] [Indexed: 02/08/2023]
Abstract
Akt signaling plays a central role in T cell functions, such as proliferation, apoptosis, and regulatory T cell development. Phosphorylation at Ser(473) in the hydrophobic motif, along with Thr(308) in its activation loop, is considered necessary for Akt function. It is widely accepted that phosphoinositide-dependent kinase 1 (PDK-1) phosphorylates Akt at Thr(308), but the kinase(s) responsible for phosphorylating Akt at Ser(473) (PDK-2) remains elusive. The existence of PDK-2 is considered to be specific to cell type and stimulus. PDK-2 in T cells in response to TCR stimulation has not been clearly defined. In this study, we found that conventional PKC positively regulated TCR-induced Akt Ser(473) phosphorylation. PKC-alpha purified from T cells can phosphorylate Akt at Ser(473) in vitro upon TCR stimulation. Knockdown of PKC-alpha in T-cell-line Jurkat cells reduced TCR-induced phosphorylation of Akt as well as its downstream targets. Thus our results suggest that PKC-alpha is a candidate for PDK-2 in T cells upon TCR stimulation.
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Affiliation(s)
- Lifen Yang
- Department of Pediatrics, Xiangya Hospital, Central South University, Changsha, Hunan, PR China
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40
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Riha P, Rudd CE. CD28 co-signaling in the adaptive immune response. SELF NONSELF 2010; 1:231-240. [PMID: 21487479 DOI: 10.4161/self.1.3.12968] [Citation(s) in RCA: 57] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Received: 07/12/2010] [Accepted: 07/12/2010] [Indexed: 12/20/2022]
Abstract
T-cell proliferation and function depends on signals from the antigen-receptor complex (TCR/CD3) and by various co-receptors such as CD28 and CTLA-4. The balance of positive and negative signals determines the outcome of the T-cell response to foreign and self-antigen. CD28 is a prominent co-receptor in naïve and memory T-cell responses. Its blockade has been exploited clinically to dampen T-cell responses to self-antigen. Current evidence shows that CD28 both potentiates TCR signaling and engages a unique array of mediators (PI3K, Grb2, FLNa) in the regulation of aspects of T-cell signaling including the transcription factor NFkB. In this mini-review, we provide an up-to-date overview of our understanding of the signaling mechanisms that underlie CD28 function and its potential application to the modulation of reactivity to autoimmunity.
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Affiliation(s)
- Pavel Riha
- Cell Signaling Section; Department of Pathology; University of Cambridge; Cambridge, UK
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41
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Abstract
Networks of signal transducers determine the conversion of environmental cues into cellular actions. Among the main players in these networks are protein kinases, which can acutely and reversibly modify protein functions to influence cellular events. One group of kinases, the protein kinase C (PKC) family, have been increasingly implicated in the organization of signal propagation, particularly in the spatial distribution of signals. Examples of where and how various PKC isoforms direct this tier of signal organization are becoming more evident.
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Aggregation of spectrin and PKCtheta is an early hallmark of fludarabine/mitoxantrone/dexamethasone-induced apoptosis in Jurkat T and HL60 cells. Mol Cell Biochem 2010; 339:63-77. [PMID: 20058056 DOI: 10.1007/s11010-009-0370-4] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2009] [Accepted: 12/16/2009] [Indexed: 12/20/2022]
Abstract
It has been shown that changes in spectrin distribution in early apoptosis preceded changes in membrane asymmetry and phosphatidylserine (PS) exposure. PKCtheta was associated with spectrin during these changes, suggesting a possible role of spectrin/PKCtheta aggregation in regulation of early apoptotic events. Here we dissect this hypothesis using Jurkat T and HL60 cell lines as model systems. Immunofluorescent analysis of alphaIIbetaII spectrin arrangement in Jurkat T and HL60 cell lines revealed the redistribution of spectrin and PKCtheta into a polar aggregate in early apoptosis induced by fludarabine/mitoxantrone/dexamethasone (FND). The appearance of an alphaIIbetaII spectrin fraction that was insoluble in a non-ionic detergent (1% Triton X-100) was observed concomitantly with spectrin aggregation. The changes were observed within 2 h after cell exposure to FND, and preceded PS exposure. The changes seem to be restricted to spectrin and not to other cytoskeletal proteins such as actin or vimentin. In studies of the mechanism of these changes, we found that (i) neither changes in apoptosis regulatory genes (e.g., Bcl-2 family proteins) nor changes in cytoskeleton-associated proteins were detected in gene expression profiling of HL60 cells after the first hour of FND treatment, (ii) caspase-3, -7, -8, and -10 had minor involvement in the early apoptotic rearrangement of spectrin/PKCtheta, and (iii) spectrin aggregation was shown to be partially dependent on PKCtheta activity. Our results indicate that spectrin/PKCtheta aggregate formation is related to an early stage in drug-induced apoptosis and possibly may be regulated by PKCtheta activity. These findings indicate that spectrin/PKCtheta aggregation could be considered as a hallmark of early apoptosis and presents the potential to become a useful diagnostic tool for monitoring efficiency of chemotherapy as early as 24 h after treatment.
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Ramesh TP, Kim YD, Kwon MS, Jun CD, Kim SW. Swiprosin-1 Regulates Cytokine Expression of Human Mast Cell Line HMC-1 through Actin Remodeling. Immune Netw 2009; 9:274-84. [PMID: 20157615 PMCID: PMC2816961 DOI: 10.4110/in.2009.9.6.274] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2009] [Revised: 12/16/2009] [Accepted: 12/21/2009] [Indexed: 01/13/2023] Open
Abstract
Background Swiprosin-1 was identified in human CD8+ lymphocytes, mature B cells and non-lymphonoid tissue. We have recently reported that swiprosin-1 is expressed in mast cells and up-regulated in both in vitro and in vivo. Methods The expression of cytokines and swiprosin-1 were determined by by real time PCR and conventional PCR. Pharmacological inhibitors were treated to investigate potential mechanism of swiprosin-1 in mast cell activation. Actin content was evaluated by confocal microscopy and flow cytometry. Results The swiprosin-1 augmented PMA/A23187-induced expression of cytokines and release of histamine. However, knock-down of swiprosin-1 showed only a modest effect on PMA/A23187-induced cytokine expression, suggesting that swiprosin-1 has gain-of-function characteristics. Swiprosin-1 was found in microvilli-like membrane protrusions and highly co-localized with F-actin. Importantly, either disruption of actin by cytochalasin B or inhibition of PI3 kinase, an enzyme involved in actin remodeling, by wortmannin blocked cytokine expression only in swiprosin-1-overexpressing
cells. Conclusion These results suggest that swiprosin-1 modulates mast cell activation potentially through actin regulation.
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Affiliation(s)
- T P Ramesh
- Department of Life Science, Gwangju Institute of Science and Technology, Gwangju 500-712, Korea
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Pores-Fernando AT, Zweifach A. Calcium influx and signaling in cytotoxic T-lymphocyte lytic granule exocytosis. Immunol Rev 2009; 231:160-73. [PMID: 19754896 DOI: 10.1111/j.1600-065x.2009.00809.x] [Citation(s) in RCA: 67] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Cytotoxic T lymphocytes (CTLs) kill targets by releasing cytotoxic agents from lytic granules. Killing is a multi-step process. The CTL adheres to a target, allowing its T-cell receptors to recognize antigen. This triggers a signal transduction cascade that leads to the polarization of the microtubule cytoskeleton and granules towards the target, followed by exocytosis that occurs specifically at the site of contact. As with cytokine production by helper T cells (Th cells), target cell killing is absolutely dependent on Ca2+ influx, which is involved in regulating both reorientation and release. Current evidence suggests that Ca2+ influx in CTLs, as in Th cells, occurs via depletion-activated channels. The molecules that couple increases in Ca2+ to reorientation are unknown. The Ca2+/calmodulin-dependent phosphatase calcineurin, which plays a critical role in cytokine production by Th cells, is also involved in lytic granule exocytosis, although the relevant substrates remain to be identified and calcineurin activation is only one Ca2+-dependent step involved. There are thus striking similarities and important differences between Ca2+ signals in Th cells and CTLs, illustrating how cells can use similar signal transduction pathways to generate different functional outcomes.
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Affiliation(s)
- Arun T Pores-Fernando
- Department of Molecular and Cell Biology, University of Connecticut, Storrs, CT, USA
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45
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E3 ubiquitin ligase GRAIL controls primary T cell activation and oral tolerance. Proc Natl Acad Sci U S A 2009; 106:16770-5. [PMID: 19805371 DOI: 10.1073/pnas.0908957106] [Citation(s) in RCA: 68] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
T cell unresponsiveness or anergy is one of the mechanisms that maintain inactivity of self-reactive lymphocytes. E3 ubiquitin ligases are important mediators of the anergic state. The RING finger E3 ligase GRAIL is thought to selectively function in anergic T cells but its mechanism of action and its role in vivo are largely unknown. We show here that genetic deletion of Grail in mice leads not only to loss of an anergic phenotype in various models but also to hyperactivation of primary CD4(+) T cells. Grail(-/-) CD4(+) T cells hyperproliferate in vitro to TCR stimulation alone or with concomitant anti-CD28 costimulation, with transient increased survival. In vitro differentiated T helper 1 cells show slight but significant hypersecretion of IFN-gamma in Grail(-/-) mice whereas Th2 and Th17 cytokine secretions are unchanged. Consistent with defective in vitro anergy, oral tolerance is abolished in vivo in OT-II TCR transgenic Grail(-/-) mice fed with ovalbumin. In experimental allergic encephalitis, a model of organ-specific autoimmunity, oral tolerization with myelin basic protein was abrogated as well in Grail(-/-) mice. On the protein level, Grail(-/-) naïve T cells show no significant differences of total and phosphorylated levels of ZAP70, phospholipase Cgamma1, and MAP kinases p38 and JNK but elevated baseline levels of MAP kinase ERK1/2. In summary, we define a role for GRAIL in primary T cell activation, survival, and differentiation. In addition, we formally prove an indispensable role for GRAIL in T cell anergy and oral tolerance-a promising, antigen-specific strategy to treat autoimmune diseases.
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Aguiló JI, Garaude J, Pardo J, Villalba M, Anel A. Protein Kinase C-θ Is Required for NK Cell Activation and In Vivo Control of Tumor Progression. THE JOURNAL OF IMMUNOLOGY 2009; 182:1972-81. [DOI: 10.4049/jimmunol.0801820] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
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Accumulation of raft lipids in T-cell plasma membrane domains engaged in TCR signalling. EMBO J 2009; 28:466-76. [PMID: 19177148 DOI: 10.1038/emboj.2009.6] [Citation(s) in RCA: 220] [Impact Index Per Article: 14.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2008] [Accepted: 01/07/2009] [Indexed: 11/08/2022] Open
Abstract
Activating stimuli for T lymphocytes are transmitted through plasma membrane domains that form at T-cell antigen receptor (TCR) signalling foci. Here, we determined the molecular lipid composition of immunoisolated TCR activation domains. We observed that they accumulate cholesterol, sphingomyelin and saturated phosphatidylcholine species as compared with control plasma membrane fragments. This provides, for the first time, direct evidence that TCR activation domains comprise a distinct molecular lipid composition reminiscent of liquid-ordered raft phases in model membranes. Interestingly, TCR activation domains were also enriched in plasmenyl phosphatidylethanolamine and phosphatidylserine. Modulating the T-cell lipidome with polyunsaturated fatty acids impaired the plasma membrane condensation at TCR signalling foci and resulted in a perturbed molecular lipid composition. These results correlate the accumulation of specific molecular lipid species with the specific plasma membrane condensation at sites of TCR activation and with early TCR activation responses.
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Abstract
It is now apparent that naïve peripheral T cells are a dynamic population where active processes prevent inappropriate activation while supporting survival. The process of thymic education makes naïve peripheral T cells dependent on interactions with self-MHC for survival. However, as these signals can potentially result in inappropriate activation, various non-redundant, intrinsic negative regulatory molecules including Tob, Nfatc2, and Smad3 actively enforce T cell quiescence. Interactions among these pathways are only now coming to light and may include positive or negative crosstalk. In the case of positive crosstalk, self-MHC initiated signals and intrinsic negative regulatory factors may cooperate to dampen T cell activation and sustain peripheral tolerance in a binary fashion (on-off). In the case of negative crosstalk, self-MHC signals may promote survival through partial activation while intrinsic negative regulatory factors act as rheostats to restrain cell cycle entry and prevent T cells from crossing a threshold that would break tolerance.
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Affiliation(s)
- Jaime F Modiano
- Integrated Department of Immunology, University of Colorado-Denver, Denver, CO, USA.
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Shen K, Thomas VK, Dustin ML, Kam LC. Micropatterning of costimulatory ligands enhances CD4+ T cell function. Proc Natl Acad Sci U S A 2008; 105:7791-6. [PMID: 18505845 PMCID: PMC2409411 DOI: 10.1073/pnas.0710295105] [Citation(s) in RCA: 99] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2007] [Indexed: 12/24/2022] Open
Abstract
Spatial organization of signaling complexes is a defining characteristic of the immunological synapse (IS), but its impact on cell communication is unclear. In T cell-APC pairs, more IL-2 is produced when CD28 clusters are segregated from central supramolecular activation cluster (cSMAC)-localized CD3 and into the IS periphery. However, it is not clear in these cellular experiments whether the increased IL-2 is driven by the pattern itself or by upstream events that precipitate the patterns. In this article, we recapitulate key features of physiological synapses using planar costimulation arrays containing antibodies against CD3 and CD28, surrounded by ICAM-1, created by combining multiple rounds of microcontact printing on a single surface. Naïve T cells traverse these arrays, stopping at features of anti-CD3 antibodies and forming a stable synapse. We directly demonstrate that presenting anti-CD28 in the cell periphery, surrounding an anti-CD3 feature, enhances IL-2 secretion by naïve CD4(+) T cells compared with having these signals combined in the center of the IS. This increased cytokine production correlates with NF-kappaB translocation and requires PKB/Akt signaling. The ability to arbitrarily and independently control the locations of anti-CD3 and anti-CD28 offered the opportunity to examine patterns not precisely attainable in cell-cell interfaces. With these patterns, we show that the peripheral presentation of CD28 has a larger impact on IL-2 secretion than CD3 colocalization/segregation.
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Affiliation(s)
- Keyue Shen
- *Department of Biomedical Engineering, Columbia University, New York, NY 10027; and
| | - V. Kaye Thomas
- Molecular Pathogenesis Program, Skirball Institute of Biomolecular Medicine, New York University School of Medicine, New York, NY 10016
| | - Michael L. Dustin
- Molecular Pathogenesis Program, Skirball Institute of Biomolecular Medicine, New York University School of Medicine, New York, NY 10016
| | - Lance C. Kam
- *Department of Biomedical Engineering, Columbia University, New York, NY 10027; and
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Ou WB, Zhu MJ, Demetri GD, Fletcher CDM, Fletcher JA. Protein kinase C-theta regulates KIT expression and proliferation in gastrointestinal stromal tumors. Oncogene 2008; 27:5624-34. [PMID: 18521081 DOI: 10.1038/onc.2008.177] [Citation(s) in RCA: 59] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Oncogenic KIT or PDGFRA receptor tyrosine kinase mutations are compelling therapeutic targets in gastrointestinal stromal tumors (GISTs), and the KIT/PDGFRA kinase inhibitor, imatinib, is standard of care for patients with metastatic GIST. However, most of these patients eventually develop clinical resistance to imatinib and other KIT/PDGFRA kinase inhibitors and there is an urgent need to identify novel therapeutic strategies. We reported previously that protein kinase C-theta (PKCtheta) is activated in GIST, irrespective of KIT or PDGFRA mutational status, and is expressed at levels unprecedented in other mesenchymal tumors, therefore serving as a diagnostic marker of GIST. Herein, we characterize biological functions of PKCtheta in imatinib-sensitive and imatinib-resistant GISTs, showing that lentivirus-mediated PKCtheta knockdown is accompanied by inhibition of KIT expression in three KIT+/PKCtheta+ GIST cell lines, but not in a comparator KIT+/PKCtheta- Ewing's sarcoma cell line. PKCtheta knockdown in the KIT+ GISTs was associated with inhibition of the phosphatidylinositol-3-kinase/AKT signaling pathway, upregulation of the cyclin-dependent kinase inhibitors p21 and p27, antiproliferative effects due to G(1) arrest and induction of apoptosis, comparable to the effects seen after direct knockdown of KIT expression by KIT short-hairpin RNA. These novel findings highlight that PKCtheta warrants clinical evaluation as a potential therapeutic target in GISTs, including those cases containing mutations that confer resistance to KIT/PDGFRA kinase inhibitors.
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Affiliation(s)
- W-b Ou
- 1Department of Pathology, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, USA.
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