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Ryan A, Janosko CP, Courtney TM, Deiters A. Engineering SHP2 Phosphatase for Optical Control. Biochemistry 2022; 61:2687-2697. [DOI: 10.1021/acs.biochem.2c00387] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Amy Ryan
- Department of Chemistry, University of Pittsburgh, Pittsburgh, Pennsylvania 15260, United States
| | - Chasity P. Janosko
- Department of Chemistry, University of Pittsburgh, Pittsburgh, Pennsylvania 15260, United States
| | - Taylor M. Courtney
- Department of Chemistry, University of Pittsburgh, Pittsburgh, Pennsylvania 15260, United States
| | - Alexander Deiters
- Department of Chemistry, University of Pittsburgh, Pittsburgh, Pennsylvania 15260, United States
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2
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Hexachlorophene, a selective SHP2 inhibitor, suppresses proliferation and metastasis of KRAS-mutant NSCLC cells by inhibiting RAS/MEK/ERK and PI3K/AKT signaling pathways. Toxicol Appl Pharmacol 2022; 441:115988. [DOI: 10.1016/j.taap.2022.115988] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2021] [Revised: 03/04/2022] [Accepted: 03/14/2022] [Indexed: 12/25/2022]
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3
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Vemulapalli V, Chylek LA, Erickson A, Pfeiffer A, Gabriel KH, LaRochelle J, Subramanian K, Cao R, Stegmaier K, Mohseni M, LaMarche MJ, Acker MG, Sorger PK, Gygi SP, Blacklow SC. Time-resolved phosphoproteomics reveals scaffolding and catalysis-responsive patterns of SHP2-dependent signaling. eLife 2021; 10:64251. [PMID: 33755016 PMCID: PMC8024022 DOI: 10.7554/elife.64251] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2020] [Accepted: 03/21/2021] [Indexed: 12/21/2022] Open
Abstract
SHP2 is a protein tyrosine phosphatase that normally potentiates intracellular signaling by growth factors, antigen receptors, and some cytokines, yet is frequently mutated in human cancer. Here, we examine the role of SHP2 in the responses of breast cancer cells to EGF by monitoring phosphoproteome dynamics when SHP2 is allosterically inhibited by SHP099. The dynamics of phosphotyrosine abundance at more than 400 tyrosine residues reveal six distinct response signatures following SHP099 treatment and washout. Remarkably, in addition to newly identified substrate sites on proteins such as occludin, ARHGAP35, and PLCγ2, another class of sites shows reduced phosphotyrosine abundance upon SHP2 inhibition. Sites of decreased phospho-abundance are enriched on proteins with two nearby phosphotyrosine residues, which can be directly protected from dephosphorylation by the paired SH2 domains of SHP2 itself. These findings highlight the distinct roles of the scaffolding and catalytic activities of SHP2 in effecting a transmembrane signaling response.
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Affiliation(s)
- Vidyasiri Vemulapalli
- Department of Cancer Biology, Dana-Farber Cancer Institute Boston, Boston, United States.,Department of Biological Chemistry & Molecular Pharmacology, Blavatnik Institute, Harvard Medical School, Boston, United States
| | - Lily A Chylek
- Laboratory of Systems Pharmacology, Harvard Medical School, Boston, United States
| | - Alison Erickson
- Department of Cell Biology, Harvard Medical School, Boston, United States
| | - Anamarija Pfeiffer
- Novo Nordisk Foundation Center for Protein Research, University of Copenhagen, Copenhagen, Denmark
| | - Khal-Hentz Gabriel
- Department of Cancer Biology, Dana-Farber Cancer Institute Boston, Boston, United States.,Department of Biological Chemistry & Molecular Pharmacology, Blavatnik Institute, Harvard Medical School, Boston, United States
| | - Jonathan LaRochelle
- Department of Cancer Biology, Dana-Farber Cancer Institute Boston, Boston, United States.,Department of Biological Chemistry & Molecular Pharmacology, Blavatnik Institute, Harvard Medical School, Boston, United States
| | - Kartik Subramanian
- Laboratory of Systems Pharmacology, Harvard Medical School, Boston, United States
| | - Ruili Cao
- Department of Cancer Biology, Dana-Farber Cancer Institute Boston, Boston, United States
| | - Kimberley Stegmaier
- Department of Pediatric Oncology, Dana Farber Cancer Institute, Boston, United States
| | - Morvarid Mohseni
- Novartis Institutes for Biomedical Research, Cambridge, United States
| | | | - Michael G Acker
- Novartis Institutes for Biomedical Research, Cambridge, United States
| | - Peter K Sorger
- Laboratory of Systems Pharmacology, Harvard Medical School, Boston, United States
| | - Steven P Gygi
- Department of Cell Biology, Harvard Medical School, Boston, United States
| | - Stephen C Blacklow
- Department of Cancer Biology, Dana-Farber Cancer Institute Boston, Boston, United States.,Department of Biological Chemistry & Molecular Pharmacology, Blavatnik Institute, Harvard Medical School, Boston, United States
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4
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Ahmed TA, Adamopoulos C, Karoulia Z, Wu X, Sachidanandam R, Aaronson SA, Poulikakos PI. SHP2 Drives Adaptive Resistance to ERK Signaling Inhibition in Molecularly Defined Subsets of ERK-Dependent Tumors. Cell Rep 2020; 26:65-78.e5. [PMID: 30605687 PMCID: PMC6396678 DOI: 10.1016/j.celrep.2018.12.013] [Citation(s) in RCA: 127] [Impact Index Per Article: 31.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2018] [Revised: 10/08/2018] [Accepted: 12/03/2018] [Indexed: 02/04/2023] Open
Abstract
Pharmacologic targeting of components of ERK signaling in ERK-dependent tumors is often limited by adaptive resistance, frequently mediated by feedback-activation of RTK signaling and rebound of ERK activity. Here, we show that combinatorial pharmacologic targeting of ERK signaling and the SHP2 phosphatase prevents adaptive resistance in defined subsets of ERK-dependent tumors. In each tumor that was sensitive to combined treatment, p(Y542)SHP2 induction was observed in response to ERK signaling inhibition. The strategy was broadly effective in TNBC models and tumors with RAS mutations at G12, whereas tumors with RAS(G13D) or RAS(Q61X) mutations were resistant. In addition, we identified a subset of BRAF(V600E) tumors that were resistant to the combined treatment, in which FGFR was found to drive feedback-induced RAS activation, independently of SHP2. Thus, we identify molecular determinants of response to combined ERK signaling and SHP2 inhibition in ERK-dependent tumors.
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Affiliation(s)
- Tamer A Ahmed
- Department of Oncological Sciences, The Tisch Cancer Institute, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA; Department of Dermatology, The Tisch Cancer Institute, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
| | - Christos Adamopoulos
- Department of Oncological Sciences, The Tisch Cancer Institute, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA; Department of Dermatology, The Tisch Cancer Institute, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
| | - Zoi Karoulia
- Department of Oncological Sciences, The Tisch Cancer Institute, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA; Department of Dermatology, The Tisch Cancer Institute, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
| | - Xuewei Wu
- Department of Oncological Sciences, The Tisch Cancer Institute, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA; Department of Dermatology, The Tisch Cancer Institute, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
| | - Ravi Sachidanandam
- Department of Oncological Sciences, The Tisch Cancer Institute, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
| | - Stuart A Aaronson
- Department of Oncological Sciences, The Tisch Cancer Institute, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA; Department of Medicine, The Tisch Cancer Institute, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
| | - Poulikos I Poulikakos
- Department of Oncological Sciences, The Tisch Cancer Institute, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA; Department of Dermatology, The Tisch Cancer Institute, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA.
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5
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Kramer F, Dernedde J, Mezheyeuski A, Tauber R, Micke P, Kappert K. Platelet-derived growth factor receptor β activation and regulation in murine myelofibrosis. Haematologica 2019; 105:2083-2094. [PMID: 31672904 PMCID: PMC7395273 DOI: 10.3324/haematol.2019.226332] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2019] [Accepted: 10/29/2019] [Indexed: 12/17/2022] Open
Abstract
There is prevailing evidence to suggest a decisive role for platelet-derived growth factors (PDGF) and their receptors in primary myelofibrosis. While PDGF receptor β (PDGFRβ) expression is increased in bone marrow stromal cells of patients correlating with the grade of myelofibrosis, knowledge on the precise role of PDGFRβ signaling in myelofibrosis is sparse. Using the Gata-1low mouse model for myelofibrosis, we applied RNA sequencing, protein expression analyses, multispectral imaging and, as a novel approach in bone marrow tissue, an in situ proximity ligation assay to provide a detailed characterization of PDGFRβ signaling and regulation during development of myelofibrosis. We observed an increase in PDGFRβ and PDGF-B protein expression in overt fibrotic bone marrow, along with an increase in PDGFRβ–PDGF-B interaction, analyzed by proximity ligation assay. However, PDGFRβ tyrosine phosphorylation levels were not increased. We therefore focused on regulation of PDGFRβ by protein tyrosine phosphatases as endogenous PDGFRβ antagonists. Gene expression analyses showed distinct expression dynamics among PDGFRβ-targeting phosphatases. In particular, we observed enhanced T-cell protein tyrosine phosphatase protein expression and PDGFRβ–T-cell protein tyrosine phosphatase interaction in early and overt fibrotic bone marrow of Gata-1low mice. In vitro, T-cell protein tyrosine phosphatase (Ptpn2) knockdown increased PDGFRβ phosphorylation at Y751 and Y1021, leading to enhanced downstream signaling in fibroblasts. Furthermore, Ptpn2 knockdown cells showed increased growth rates when exposed to low-serum growth medium. Taken together, PDGF signaling is differentially regulated during myelofibrosis. Protein tyrosine phosphatases, which have so far not been examined during disease progression, are novel and hitherto unrecognized components in myelofibrosis.
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Affiliation(s)
- Frederike Kramer
- Charité - Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Institute of Laboratory Medicine, Clinical Chemistry and Pathobiochemistry, Berlin, Germany.,Charité -Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Center for Cardiovascular Research (CCR), Berlin, Germany
| | - Jens Dernedde
- Charité - Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Institute of Laboratory Medicine, Clinical Chemistry and Pathobiochemistry, Berlin, Germany
| | - Artur Mezheyeuski
- Department of Immunology, Genetics and Pathology, Uppsala University, Uppsala, Sweden
| | - Rudolf Tauber
- Charité - Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Institute of Laboratory Medicine, Clinical Chemistry and Pathobiochemistry, Berlin, Germany
| | - Patrick Micke
- Department of Immunology, Genetics and Pathology, Uppsala University, Uppsala, Sweden
| | - Kai Kappert
- Charité - Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Institute of Laboratory Medicine, Clinical Chemistry and Pathobiochemistry, Berlin, Germany .,Charité -Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Center for Cardiovascular Research (CCR), Berlin, Germany.,DZHK (German Centre for Cardiovascular Research), partner site Berlin, Berlin, Germany
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6
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Niogret C, Birchmeier W, Guarda G. SHP-2 in Lymphocytes' Cytokine and Inhibitory Receptor Signaling. Front Immunol 2019; 10:2468. [PMID: 31708921 PMCID: PMC6823243 DOI: 10.3389/fimmu.2019.02468] [Citation(s) in RCA: 36] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2019] [Accepted: 10/03/2019] [Indexed: 02/06/2023] Open
Abstract
Somewhat counterintuitively, the tyrosine phosphatase SHP-2 (SH2 domain-containing protein tyrosine phosphatase-2) is crucial for the activation of extracellular signal-regulated kinase (ERK) downstream of various growth factor receptors, thereby exerting essential developmental functions. This phosphatase also deploys proto-oncogenic functions and specific inhibitors have recently been developed. With respect to the immune system, the role of SHP-2 in the signaling of cytokines relevant for myelopoiesis and myeloid malignancies has been intensively studied. The function of this phosphatase downstream of cytokines important for lymphocytes is less understood, though multiple lines of evidence suggest its importance. In addition, SHP-2 has been proposed to mediate the suppressive effects of inhibitory receptors (IRs) that sustain a dysfunctional state in anticancer T cells. Molecules involved in IR signaling are of potential pharmaceutical interest as blockade of these inhibitory circuits leads to remarkable clinical benefit. Here, we discuss the dichotomy in the functions ascribed to SHP-2 downstream of cytokine receptors and IRs, with a focus on T and NK lymphocytes. Further, we highlight the importance of broadening our understanding of SHP-2′s relevance in lymphocytes, an essential step to inform on side effects and unanticipated benefits of its therapeutic blockade.
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Affiliation(s)
- Charlène Niogret
- Department of Biochemistry, University of Lausanne, Épalinges, Switzerland
| | - Walter Birchmeier
- Max-Delbrueck-Center for Molecular Medicine (MDC) in the Helmholtz Society, Berlin, Germany
| | - Greta Guarda
- Institute for Research in Biomedicine, Università della Svizzera italiana, Bellinzona, Switzerland
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7
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Farrar CS, Hocking DC. Assembly of fibronectin fibrils selectively attenuates platelet-derived growth factor-induced intracellular calcium release in fibroblasts. J Biol Chem 2018; 293:18655-18666. [PMID: 30323067 PMCID: PMC6290149 DOI: 10.1074/jbc.ra118.004020] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2018] [Revised: 10/08/2018] [Indexed: 01/24/2023] Open
Abstract
Cellular responses to platelet-derived growth factor (PDGF) are altered in a variety of pathological conditions, including cancers, fibroses, and vascular diseases, making PDGF-induced signaling pathways important therapeutic targets. The limited success of therapies designed to impact PDGF pathways may be overcome with a clearer understanding of how cells integrate signals from PDGF and the extracellular matrix (ECM). Here, we assessed the effects of fibronectin matrix assembly on the responsiveness of mesenchymal cells to PDGF. Our results indicate that fibroblast-mediated assembly of fibronectin fibrils attenuates intracellular calcium release in response to PDGF. The dose-dependent inhibition of PDGF-induced intracellular calcium release was specific to the ECM form of fibronectin. Further, a recombinant protein engineered to mimic ECM fibronectin similarly attenuated intracellular calcium release in response to PDGF. Of note, fibronectin attenuated the PDGF-calcium signaling axis at the level of phosphoinositide 3-kinase (PI3K) activation. Interestingly, ECM fibronectin did not alter other intracellular signals activated by PDGF, including activation of PDGF receptor β, AKT Ser/Thr kinase, phospholipase Cγ1, and extracellular signal-regulated kinase 1/2 (ERK1/2). Rather, fibronectin inhibited activation of the p55 regulatory subunit of PI3K in response to a variety of stimuli, indicating that ECM fibronectin selectively attenuates the intracellular calcium release cascade while leaving intact other PDGF signaling pathways. Selective regulation of calcium signaling by ECM fibronectin via the p55 regulatory subunit of PI3K represents a mechanism by which cells tune their response to PDGF and may therefore serve as a target to selectively regulate one branch of PDGF signaling.
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Affiliation(s)
| | - Denise C Hocking
- From the Department of Biomedical Engineering and
- Department of Pharmacology and Physiology, University of Rochester School of Medicine and Dentistry, Rochester, New York 14642
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8
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Corti F, Simons M. Modulation of VEGF receptor 2 signaling by protein phosphatases. Pharmacol Res 2017; 115:107-123. [PMID: 27888154 PMCID: PMC5205541 DOI: 10.1016/j.phrs.2016.11.022] [Citation(s) in RCA: 37] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/04/2016] [Revised: 11/18/2016] [Accepted: 11/21/2016] [Indexed: 12/21/2022]
Abstract
Phosphorylation of serines, threonines, and tyrosines is a central event in signal transduction cascades in eukaryotic cells. The phosphorylation state of any particular protein reflects a balance of activity between kinases and phosphatases. Kinase biology has been exhaustively studied and is reasonably well understood, however, much less is known about phosphatases. A large body of evidence now shows that protein phosphatases do not behave as indiscriminate signal terminators, but can function both as negative or positive regulators of specific signaling pathways. Genetic models have also shown that different protein phosphatases play precise biological roles in health and disease. Finally, genome sequencing has unveiled the existence of many protein phosphatases and associated regulatory subunits comparable in number to kinases. A wide variety of roles for protein phosphatase roles have been recently described in the context of cancer, diabetes, hereditary disorders and other diseases. In particular, there have been several recent advances in our understanding of phosphatases involved in regulation of vascular endothelial growth factor receptor 2 (VEGFR2) signaling. The receptor is the principal signaling molecule mediating a wide spectrum of VEGF signal and, thus, is of paramount significance in a wide variety of diseases ranging from cancer to cardiovascular to ophthalmic. This review focuses on the current knowledge about protein phosphatases' regulation of VEGFR2 signaling and how these enzymes can modulate its biological effects.
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Affiliation(s)
- Federico Corti
- Yale Cardiovascular Research Center, Department of Internal Medicine and Department of Cell Biology, Yale University School of Medicine, New Haven, CT, USA.
| | - Michael Simons
- Yale Cardiovascular Research Center, Department of Internal Medicine and Department of Cell Biology, Yale University School of Medicine, New Haven, CT, USA.
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9
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Fantauzzo KA, Soriano P. PDGFRβ regulates craniofacial development through homodimers and functional heterodimers with PDGFRα. Genes Dev 2016; 30:2443-2458. [PMID: 27856617 PMCID: PMC5131783 DOI: 10.1101/gad.288746.116] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2016] [Accepted: 10/19/2016] [Indexed: 01/01/2023]
Abstract
Craniofacial development is a complex morphogenetic process, disruptions in which result in highly prevalent human birth defects. While platelet-derived growth factor (PDGF) receptor α (PDGFRα) has well-documented functions in this process, the role of PDGFRβ in murine craniofacial development is not well established. We demonstrate that PDGFRα and PDGFRβ are coexpressed in the craniofacial mesenchyme of mid-gestation mouse embryos and that ablation of Pdgfrb in the neural crest lineage results in increased nasal septum width, delayed palatal shelf development, and subepidermal blebbing. Furthermore, we show that the two receptors genetically interact in this lineage, as double-homozygous mutant embryos exhibit an overt facial clefting phenotype more severe than that observed in either single-mutant embryo. We reveal a physical interaction between PDGFRα and PDGFRβ in the craniofacial mesenchyme and demonstrate that the receptors form functional heterodimers with distinct signaling properties. Our studies thus uncover a novel mode of signaling for the PDGF family during vertebrate development.
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Affiliation(s)
- Katherine A Fantauzzo
- Department of Cell Developmental and Regenerative Biology, Icahn School of Medicine at Mount Sinai, New York, New York 10029, USA
| | - Philippe Soriano
- Department of Cell Developmental and Regenerative Biology, Icahn School of Medicine at Mount Sinai, New York, New York 10029, USA
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10
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He RJ, Yu ZH, Zhang RY, Zhang ZY. Protein tyrosine phosphatases as potential therapeutic targets. Acta Pharmacol Sin 2014; 35:1227-46. [PMID: 25220640 DOI: 10.1038/aps.2014.80] [Citation(s) in RCA: 228] [Impact Index Per Article: 22.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2014] [Accepted: 07/31/2014] [Indexed: 12/17/2022] Open
Abstract
Protein tyrosine phosphorylation is a key regulatory process in virtually all aspects of cellular functions. Dysregulation of protein tyrosine phosphorylation is a major cause of human diseases, such as cancers, diabetes, autoimmune disorders, and neurological diseases. Indeed, protein tyrosine phosphorylation-mediated signaling events offer ample therapeutic targets, and drug discovery efforts to date have brought over two dozen kinase inhibitors to the clinic. Accordingly, protein tyrosine phosphatases (PTPs) are considered next-generation drug targets. For instance, PTP1B is a well-known targets of type 2 diabetes and obesity, and recent studies indicate that it is also a promising target for breast cancer. SHP2 is a bona-fide oncoprotein, mutations of which cause juvenile myelomonocytic leukemia, acute myeloid leukemia, and solid tumors. In addition, LYP is strongly associated with type 1 diabetes and many other autoimmune diseases. This review summarizes recent findings on several highly recognized PTP family drug targets, including PTP1B, Src homology phosphotyrosyl phosphatase 2(SHP2), lymphoid-specific tyrosine phosphatase (LYP), CD45, Fas associated phosphatase-1 (FAP-1), striatal enriched tyrosine phosphatases (STEP), mitogen-activated protein kinase/dual-specificity phosphatase 1 (MKP-1), phosphatases of regenerating liver-1 (PRL), low molecular weight PTPs (LMWPTP), and CDC25. Given that there are over 100 family members, we hope this review will serve as a road map for innovative drug discovery targeting PTPs.
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11
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Abrantes JLF, Tornatore TF, Pelizzaro-Rocha KJ, de Jesus MB, Cartaxo RT, Milani R, Ferreira-Halder CV. Crosstalk between kinases, phosphatases and miRNAs in cancer. Biochimie 2014; 107 Pt B:167-87. [PMID: 25230087 DOI: 10.1016/j.biochi.2014.09.011] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2014] [Accepted: 09/04/2014] [Indexed: 02/07/2023]
Abstract
Reversible phosphorylation of proteins, performed by kinases and phosphatases, is the major post translational protein modification in eukaryotic cells. This intracellular event represents a critical regulatory mechanism of several signaling pathways and can be related to a vast array of diseases, including cancer. Cancer research has produced increasing evidence that kinase and phosphatase activity can be compromised by mutations and also by miRNA silencing, performed by small non-coding and endogenously produced RNA molecules that lead to translational repression. miRNAs are believed to target about one-third of human mRNAs while a single miRNA may target about 200 transcripts simultaneously. Regulation of the phosphorylation balance by miRNAs has been a topic of intense research over the last years, spanning topics going as far as cancer aggressiveness and chemotherapy resistance. By addressing recent studies that have shown miRNA expression patterns as phenotypic signatures of cancers and how miRNA influence cellular processes such as apoptosis, cell cycle control, angiogenesis, inflammation and DNA repair, we discuss how kinases, phosphatases and miRNAs cooperatively act in cancer biology.
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Affiliation(s)
- Júlia L F Abrantes
- Department of Biochemistry, Institute of Biology, UNICAMP, 13083-970 Campinas, Brazil
| | - Thaís F Tornatore
- Department of Biochemistry, Institute of Biology, UNICAMP, 13083-970 Campinas, Brazil
| | | | - Marcelo B de Jesus
- Department of Biochemistry, Institute of Biology, UNICAMP, 13083-970 Campinas, Brazil
| | - Rodrigo T Cartaxo
- Department of Biochemistry, Institute of Biology, UNICAMP, 13083-970 Campinas, Brazil
| | - Renato Milani
- Department of Biochemistry, Institute of Biology, UNICAMP, 13083-970 Campinas, Brazil
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12
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Inhibition of protein tyrosine phosphatases enhances cerebral collateral growth in rats. J Mol Med (Berl) 2014; 92:983-94. [PMID: 24858946 DOI: 10.1007/s00109-014-1164-z] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2014] [Revised: 04/13/2014] [Accepted: 05/07/2014] [Indexed: 12/27/2022]
Abstract
UNLABELLED Arteriogenesis involves the rapid proliferation of preexisting arterioles to fully functional arteries as a compensatory mechanism to overcome circulatory deficits. Stimulation of arteriogenesis has therefore been considered a treatment concept in arterial occlusive disease. Here, we investigated the impact of inhibition of protein tyrosine phosphatases (PTPs) on cerebral arteriogenesis in rats. Arteriogenesis was induced by occlusion of one carotid and both vertebral arteries (three-vessel occlusion (3-VO)). Collateral growth and functional vessel perfusion was assessed 3-35 days following 3-VO. Furthermore, animals underwent 3-VO surgery and were treated with the pan-PTP inhibitor BMOV, the SHP-1 inhibitor sodium stibogluconate (SSG), or the PTP1B inhibitor AS279. Cerebral vessel diameters and cerebrovascular reserve capacity (CVRC) were determined, together with immunohistochemistry analyses and proximity ligation assays (PLA) for determination of tissue proliferation and phosphorylation patterns after 7 days. The most significant changes in vessel diameter increase were present in the ipsilateral posterior cerebral artery (PCA), with proliferative markers (PCNA) being time-dependently increased. The CVRC was lost in the early phase after 3-VO and partially recovered after 21 days. PTP inhibition resulted in a significant increase in the ipsilateral PCA diameter in BMOV-treated animals and rats subjected to PTP1B inhibition. Furthermore, CVRC was significantly elevated in AS279-treated rats compared to control animals, along with hyperphosphorylation of the platelet-derived growth factor-β receptor in the vascular wall in vivo. In summary, our data indicate PTPs as hitherto unrecognized negative regulators in cerebral arteriogenesis. Further, PTP inhibition leading to enhanced collateral growth and blood perfusion suggests PTPs as novel targets in anti-ischemic treatment. KEY MESSAGES PTPs exhibit negative regulatory function in cerebral collateral growth in rats. Inhibition of pan-PTP/PTP1B increases vessel PDGF-β receptor phosphorylation. PTP1B inhibition enhances arteriogenesis and cerebrovascular reserve capacity.
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13
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Selective activation of oxidized PTP1B by the thioredoxin system modulates PDGF-β receptor tyrosine kinase signaling. Proc Natl Acad Sci U S A 2013; 110:13398-403. [PMID: 23901112 DOI: 10.1073/pnas.1302891110] [Citation(s) in RCA: 71] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
The inhibitory reversible oxidation of protein tyrosine phosphatases (PTPs) is an important regulatory mechanism in growth factor signaling. Studies on PTP oxidation have focused on pathways that increase or decrease reactive oxygen species levels and thereby affect PTP oxidation. The processes involved in reactivation of oxidized PTPs remain largely unknown. Here the role of the thioredoxin (Trx) system in reactivation of oxidized PTPs was analyzed using a combination of in vitro and cell-based assays. Cells lacking the major Trx reductase TrxR1 (Txnrd1(-/-)) displayed increased oxidation of PTP1B, whereas SHP2 oxidation was unchanged. Furthermore, in vivo-oxidized PTP1B was reduced by exogenously added Trx system components, whereas SHP2 oxidation remained unchanged. Trx1 reduced oxidized PTP1B in vitro but failed to reactivate oxidized SHP2. Interestingly, the alternative TrxR1 substrate TRP14 also reactivated oxidized PTP1B, but not SHP2. Txnrd1-depleted cells displayed increased phosphorylation of PDGF-β receptor, and an enhanced mitogenic response, after PDGF-BB stimulation. The TrxR inhibitor auranofin also increased PDGF-β receptor phosphorylation. This effect was not observed in cells specifically lacking PTP1B. Together these results demonstrate that the Trx system, including both Trx1 and TRP14, impacts differentially on the oxidation of individual PTPs, with a preference of PTP1B over SHP2 activation. The studies demonstrate a previously unrecognized pathway for selective redox-regulated control of receptor tyrosine kinase signaling.
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14
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Craig J, Mikhailenko I, Noyes N, Migliorini M, Strickland DK. The LDL receptor-related protein 1 (LRP1) regulates the PDGF signaling pathway by binding the protein phosphatase SHP-2 and modulating SHP-2- mediated PDGF signaling events. PLoS One 2013; 8:e70432. [PMID: 23922991 PMCID: PMC3724782 DOI: 10.1371/journal.pone.0070432] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2013] [Accepted: 06/18/2013] [Indexed: 02/05/2023] Open
Abstract
BACKGROUND The PDGF signaling pathway plays a major role in several biological systems, including vascular remodeling that occurs following percutaneous transluminal coronary angioplasty. Recent studies have shown that the LDL receptor-related protein 1 (LRP1) is a physiological regulator of the PDGF signaling pathway. The underlying mechanistic details of how this regulation occurs have yet to be resolved. Activation of the PDGF receptor β (PDGFRβ) leads to tyrosine phosphorylation of the LRP1 cytoplasmic domain within endosomes and generates an LRP1 molecule with increased affinity for adaptor proteins such as SHP-2 that are involved in signaling pathways. SHP-2 is a protein tyrosine phosphatase that positively regulates the PDGFRβ pathway, and is required for PDGF-mediated chemotaxis. We investigated the possibility that LRP1 may regulate the PDGFRβ signaling pathway by binding SHP-2 and competing with the PDGFRβ for this molecule. METHODOLOGY/PRINCIPAL FINDINGS To quantify the interaction between SHP-2 and phosphorylated forms of the LRP1 intracellular domain, we utilized an ELISA with purified recombinant proteins. These studies revealed high affinity binding of SHP-2 to phosphorylated forms of both LRP1 intracellular domain and the PDGFRβ kinase domain. By employing the well characterized dynamin inhibitor, dynasore, we established that PDGF-induced SHP-2 phosphorylation primarily occurs within endosomal compartments, the same compartments in which LRP1 is tyrosine phosphorylated by activated PDGFRβ. Immunofluorescence studies revealed colocalization of LRP1 and phospho-SHP-2 following PDGF stimulation of fibroblasts. To define the contribution of LRP1 to SHP-2-mediated PDGF chemotaxis, we employed fibroblasts expressing LRP1 and deficient in LRP1 and a specific SHP-2 inhibitor, NSC-87877. Our results reveal that LRP1 modulates SHP-2-mediated PDGF-mediated chemotaxis. CONCLUSIONS/SIGNIFICANCE Our data demonstrate that phosphorylated forms of LRP1 and PDGFRβ compete for SHP-2 binding, and that expression of LRP1 attenuates SHP-2-mediated PDGF signaling events.
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Affiliation(s)
- Julie Craig
- Center for Vascular and Inflammatory Diseases and
| | - Irina Mikhailenko
- Center for Vascular and Inflammatory Diseases and
- Department of Physiology, University of Maryland School of Medicine, Baltimore, Maryland, United States of America
| | | | - Mary Migliorini
- Center for Vascular and Inflammatory Diseases and
- Department of Surgery, University of Maryland School of Medicine, Baltimore, Maryland, United States of America
| | - Dudley K. Strickland
- Center for Vascular and Inflammatory Diseases and
- Department of Physiology, University of Maryland School of Medicine, Baltimore, Maryland, United States of America
- Department of Surgery, University of Maryland School of Medicine, Baltimore, Maryland, United States of America
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Lauriol J, Kontaridis MI. PTPN11-associated mutations in the heart: has LEOPARD changed Its RASpots? Trends Cardiovasc Med 2012; 21:97-104. [PMID: 22681964 DOI: 10.1016/j.tcm.2012.03.006] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
In this review, we focus on elucidating the cardiac function of germline mutations in the PTPN11 gene, encoding the Src homology-2 (SH2) domain-containing protein tyrosine phosphatase SHP2. PTPN11 mutations cause LEOPARD syndrome (LS) and Noonan syndrome (NS), two disorders that are part of a newly classified family of autosomal dominant syndromes termed "RASopathies," which are caused by germline mutations in components of the RAS/RAF/MEK/ERK mitogen activating protein kinase pathway. LS and NS mutants have opposing biochemical properties, and yet, in patients, these mutations produce similar cardiac abnormalities. Precisely how LS and NS mutations lead to such similar disease etiology remains largely unknown. Recent complementary in vitro, ex vivo, and in vivo analyses reveal new insights into the functions of SHP2 in normal and pathological cardiac development. These findings also reveal the need for individualized therapeutic approaches in the treatment of patients with LS and NS and, more broadly, patients with the other "RASopathy" gene mutations as well.
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Affiliation(s)
- Jessica Lauriol
- Department of Medicine, Division of Cardiology, Beth Israel Deaconess Medical Center, Boston, MA 02115, USA
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16
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Tsou PS, Talia NN, Pinney AJ, Kendzicky A, Piera-Velazquez S, Jimenez SA, Seibold JR, Phillips K, Koch AE. Effect of oxidative stress on protein tyrosine phosphatase 1B in scleroderma dermal fibroblasts. ACTA ACUST UNITED AC 2011; 64:1978-89. [PMID: 22161819 DOI: 10.1002/art.34336] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
OBJECTIVE Platelet-derived growth factor (PDGF) and its receptor, PDGFR, promote fibrosis in systemic sclerosis (SSc; scleroderma) dermal fibroblasts, and such cells in scleroderma skin lesions produce excessive reactive oxygen species (ROS). PDGFR is phosphorylated upon PDGF stimulation, and is dephosphorylated by protein tyrosine phosphatases (PTPs), including PTP1B. This study was undertaken to determine whether the thiol-sensitive PTP1B is affected by ROS in SSc dermal fibroblasts, thereby enhancing the phosphorylation of PDGFR and synthesis of type I collagen. This study also sought to investigate the effect of a thiol antioxidant, N-acetylcysteine (NAC), in SSc. METHODS Fibroblasts were isolated from the skin of patients with diffuse SSc and normal healthy donors for cell culture experiments and immunofluorescence analyses. A phosphate release assay was used to determine the activity of PTP1B. RESULTS Levels of ROS and type I collagen were significantly higher and amounts of free thiol were significantly lower in SSc fibroblasts compared to normal fibroblasts. After stimulation with PDGF, not only were PDGFR and ERK-1/2 phosphorylated to a greater extent, but also the ability to produce PTP1B was hampered in SSc fibroblasts. The activity of PTP1B was significantly inactivated in SSc fibroblasts as a result of cysteine oxidation by the raised levels of ROS, which was confirmed by the oxidation of multiple PTPs, including PTP1B, in SSc fibroblasts. Decreased expression of PTP1B in normal fibroblasts led to increased expression of type I collagen. Treatment of the cells with NAC restored the activity of PTP1B, improved the profile of PDGFR phosphorylation, decreased the numbers of tyrosine-phosphorylated proteins and levels of type I collagen, and scavenged ROS in SSc fibroblasts. CONCLUSION This study describes a new mechanism by which ROS may promote a profibrotic phenotype in SSc fibroblasts through the oxidative inactivation of PTP1B, leading to pronounced activation of PDGFR. The study also presents a novel molecular mechanism by which NAC may act on ROS and PTP1B to provide therapeutic benefit in SSc.
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Affiliation(s)
- Pei-Suen Tsou
- University of Michigan Medical School, Ann Arbor, MI, USA
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17
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Zheng W, Lennartsson J, Hendriks W, Heldin CH, Hellberg C. The LAR protein tyrosine phosphatase enables PDGF β-receptor activation through attenuation of the c-Abl kinase activity. Cell Signal 2011; 23:1050-6. [DOI: 10.1016/j.cellsig.2011.01.024] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2011] [Accepted: 01/28/2011] [Indexed: 12/24/2022]
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18
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Hypoxia followed by re-oxygenation induces oxidation of tyrosine phosphatases. Cell Signal 2011; 23:820-6. [DOI: 10.1016/j.cellsig.2011.01.004] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2010] [Revised: 12/09/2010] [Accepted: 01/10/2011] [Indexed: 12/16/2022]
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19
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Ren L, Chen X, Luechapanichkul R, Selner NG, Meyer TM, Wavreille AS, Chan R, Iorio C, Zhou X, Neel BG, Pei D. Substrate specificity of protein tyrosine phosphatases 1B, RPTPα, SHP-1, and SHP-2. Biochemistry 2011; 50:2339-56. [PMID: 21291263 DOI: 10.1021/bi1014453] [Citation(s) in RCA: 73] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
We determined the substrate specificities of the protein tyrosine phosphatases (PTPs) PTP1B, RPTPα, SHP-1, and SHP-2 by on-bead screening of combinatorial peptide libraries and solution-phase kinetic analysis of individually synthesized phosphotyrosyl (pY) peptides. These PTPs exhibit different levels of sequence specificity and catalytic efficiency. The catalytic domain of RPTPα has very weak sequence specificity and is approximately 2 orders of magnitude less active than the other three PTPs. The PTP1B catalytic domain has modest preference for acidic residues on both sides of pY, is highly active toward multiply phosphorylated peptides, but disfavors basic residues at any position, a Gly at the pY-1 position, or a Pro at the pY+1 position. By contrast, SHP-1 and SHP-2 share similar but much narrower substrate specificities, with a strong preference for acidic and aromatic hydrophobic amino acids on both sides of the pY residue. An efficient SHP-1/2 substrate generally contains two or more acidic residues on the N-terminal side and one or more acidic residues on the C-terminal side of pY but no basic residues. Subtle differences exist between SHP-1 and SHP-2 in that SHP-1 has a stronger preference for acidic residues at the pY-1 and pY+1 positions and the two SHPs prefer acidic residues at different positions N-terminal to pY. A survey of the known protein substrates of PTP1B, SHP-1, and SHP-2 shows an excellent agreement between the in vivo dephosphorylation pattern and the in vitro specificity profiles derived from library screening. These results suggest that different PTPs have distinct sequence specificity profiles and the intrinsic activity/specificity of the PTP domain is an important determinant of the enzyme's in vivo substrate specificity.
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Affiliation(s)
- Lige Ren
- Department of Chemistry, The Ohio State University, 100 West 18th Avenue, Columbus, Ohio 43210, United States
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20
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Kandadi MR, Stratton MS, Ren J. The role of Src homology 2 containing protein tyrosine phosphatase 2 in vascular smooth muscle cell migration and proliferation. Acta Pharmacol Sin 2010; 31:1277-83. [PMID: 20871619 DOI: 10.1038/aps.2010.168] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Vascular smooth muscle cells (VSMCs) perform essential smooth muscle contractile and synthetic functions including migration, differentiation and proliferation under physiological and pathological conditions. In response to pathological stimuli, VMSCs undergo phenotypic change resulting in abnormal migration and proliferation, which may contribute to a "pathogenesis-like" atherosclerosis. Intracellular signaling mechanisms governing this phenotypic switch are of great significance not only for better understanding of atherosclerotic plaque formation but also for strategy for pertinent therapeutic remedies. Src Homology 2 Containing Protein Tyrosine Phosphatase 2 (SHP2) is a ubiquitous tyrosine phosphatase containing Src Homology 2 domains which plays major biological functions in response to various growth factors, hormones or cytokines. In particular, SHP2 is implicated in cell signaling pathways controlling cell cycle progression, growth and migration. In this review we will mainly discuss the recent literature demonstrating the role of SHP2 in VSMC migration and proliferation.
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21
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12/15-lipoxygenase-derived lipid peroxides control receptor tyrosine kinase signaling through oxidation of protein tyrosine phosphatases. Proc Natl Acad Sci U S A 2010; 107:15774-9. [PMID: 20798033 DOI: 10.1073/pnas.1007909107] [Citation(s) in RCA: 77] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023] Open
Abstract
Protein tyrosine phosphatases (PTPs) are regulated through reversible oxidation of the active-site cysteine. Previous studies have implied soluble reactive oxygen species (ROS), like H(2)O(2), as the mediators of PTP oxidation. The potential role(s) of peroxidized lipids in PTP oxidation have not been described. This study demonstrates that increases in cellular lipid peroxides, induced by disruption of glutathione peroxidase 4, induce cellular PTP oxidation and reduce the activity of PDGF receptor targeting PTPs. These effects were accompanied by site-selective increased PDGF beta-receptor phosphorylation, sensitive to 12/15-lipoxygenase (12/15-LOX) inhibitors, and increased PDGF-induced cytoskeletal rearrangements. Importantly, the 12/15-LOX-derived 15-OOH-eicosatetraenoic acid lipid peroxide was much more effective than H(2)O(2) in induction of in vitro PTP oxidation. Our study thus establishes that lipid peroxides are previously unrecognized inducers of oxidation of PTPs. This identifies a pathway for control of receptor tyrosine kinase signaling, which might also be involved in the etiology of diseases associated with increased lipid peroxidation.
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22
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Gao L, Sun H, Yao SQ. Activity-based high-throughput determination of PTPs substrate specificity using a phosphopeptide microarray. Biopolymers 2010; 94:810-9. [DOI: 10.1002/bip.21533] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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23
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Carver KC, Piazza TM, Schuler LA. Prolactin enhances insulin-like growth factor I receptor phosphorylation by decreasing its association with the tyrosine phosphatase SHP-2 in MCF-7 breast cancer cells. J Biol Chem 2010; 285:8003-12. [PMID: 20080972 DOI: 10.1074/jbc.m109.066480] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Normal mammary development requires coordinated interactions of numerous factors, including prolactin (PRL) and insulin-like growth factor I (IGF-I), both of which have also been implicated in breast cancer pathogenesis and progression. We previously reported that PRL and IGF-I synergize in breast cancer cells to activate ERK1/2 and AKT, leading to increased proliferation, survival, and invasion. Intriguingly, PRL co-treatment with IGF-I augments IGF-I receptor (IGF-IR) phosphorylation 2-fold higher than IGF-I alone. Here, we showed the importance of the tyrosine phosphatase SHP-2 in this cross-talk using pharmacological inhibition and small interfering RNA. SHP-2 recruitment to IGF-IR was significantly attenuated by PRL co-treatment. Src family kinase activity was required for IGF-IR association with SHP-2, ligand-induced IGF-IR internalization, and PRL-enhanced IGF-IR phosphorylation. Inhibition of internalization, via knockdown of the GTPase, dynamin-2, prevented not only IGF-IR dephosphorylation, but also PRL-enhanced IGF-IR phosphorylation. Consistently, PRL diminished IGF-I-induced IGF-IR internalization, which may result from reduced SHP-2 association with IGF-IR, because we demonstrated an essential role for SHP-2 in IGF-IR internalization. Together, these findings describe a novel mechanism of cross-talk between PRL and IGF-I in breast cancer cells, with implications for our understanding of tumor progression and potential therapeutic strategies.
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Affiliation(s)
- Kristopher C Carver
- Department of Comparative Biosciences, University of Wisconsin, Madison, Wisconsin 53706, USA
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24
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Purdy AK, Campbell KS. SHP-2 expression negatively regulates NK cell function. THE JOURNAL OF IMMUNOLOGY 2009; 183:7234-43. [PMID: 19915046 DOI: 10.4049/jimmunol.0900088] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Src homology region 2-containing protein tyrosine phosphatase-2 (SHP-2) is required for full activation of Ras/ERK in many cytokine and growth factor receptor signaling pathways. In contrast, SHP-2 inhibits activation of human NK cells upon recruitment to killer cell Ig-like receptors (KIR). To determine how SHP-2 impacts NK cell activation in KIR-dependent or KIR-independent signaling pathways, we employed knockdown and overexpression strategies in NK-like cell lines and analyzed the consequences on functional responses. In response to stimulation with susceptible target cells, SHP-2-silenced NK cells had elevated cytolytic activity and IFN-gamma production, whereas cells overexpressing wild-type or gain-of-function mutants of SHP-2 exhibited dampened activities. Increased levels of SHP-2 expression over this range significantly suppressed microtubule organizing center polarization and granzyme B release in response to target cells. Interestingly, NK-target cell conjugation was only reduced by overexpressing SHP-2, but not potentiated in SHP-2-silenced cells, indicating that conjugation is not influenced by physiological levels of SHP-2 expression. KIR-dependent inhibition of cytotoxicity was unaffected by significant reductions in SHP-2 levels, presumably because KIR were still capable of recruiting the phosphatase under these limiting conditions. In contrast, the general suppressive effect of SHP-2 on cytotoxicity and cytokine release was much more sensitive to changes in cellular SHP-2 levels. In summary, our studies have identified a new, KIR-independent role for SHP-2 in dampening NK cell activation in response to tumor target cells in a concentration-dependent manner. This suppression of activation impacts microtubule organizing center-based cytoskeletal rearrangement and granule release.
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Affiliation(s)
- Amanda K Purdy
- Fox Chase Cancer Center, Institute for Cancer Research, Philadelphia, PA 19111, USA
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25
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Matozaki T, Murata Y, Saito Y, Okazawa H, Ohnishi H. Protein tyrosine phosphatase SHP-2: a proto-oncogene product that promotes Ras activation. Cancer Sci 2009; 100:1786-93. [PMID: 19622105 PMCID: PMC11158110 DOI: 10.1111/j.1349-7006.2009.01257.x] [Citation(s) in RCA: 173] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
SHP-2 is a cytoplasmic protein tyrosine phosphatase (PTP) that contains two Src homology 2 (SH2) domains. Although PTPs are generally considered to be negative regulators on the basis of their ability to oppose the effects of protein tyrosine kinases, SHP-2 is unusual in that it promotes the activation of the Ras-MAPK signaling pathway by receptors for various growth factors and cytokines. The molecular basis for the activation of SHP-2 is also unique: In the basal state, the NH(2)-terminal SH2 domain of SHP-2 interacts with the PTP domain, resulting in autoinhibition of PTP activity; the binding of SHP-2 via its SH2 domains to tyrosine-phosphorylated growth factor receptors or docking proteins, however, results in disruption of this intramolecular interaction, leading to exposure of the PTP domain and catalytic activation. Indeed, SHP-2 proteins with artificial mutations in the NH(2)-terminal SH2 domain have been shown to act as dominant active mutants in vitro. Such activating mutations of PTPN11 (human SHP-2 gene) were subsequently identified in individuals with Noonan syndrome, a human developmental disorder that is sometimes associated with juvenile myelomonocytic leukemia. Furthermore, somatic mutations of PTPN11 were found to be associated with pediatric leukemia. SHP-2 is also thought to participate in the development of other malignant disorders, but in a manner independent of such activating mutations. Biochemical and functional studies of SHP-2 and genetic analysis of PTPN11 in human disorders have thus converged to provide new insight into the pathogenesis of cancer as well as potential new targets for cancer treatment.
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Affiliation(s)
- Takashi Matozaki
- Laboratory of Biosignal Sciences, Institute for Molecular and Cellular Regulation, Gunma University, Maebashi, Gunma, Japan.
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26
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The tyrosine phosphatase Shp2 (PTPN11) directs Neuregulin-1/ErbB signaling throughout Schwann cell development. Proc Natl Acad Sci U S A 2009; 106:16704-9. [PMID: 19805360 DOI: 10.1073/pnas.0904336106] [Citation(s) in RCA: 89] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The nonreceptor tyrosine phosphatase Shp2 (PTPN11) has been implicated in tyrosine kinase, cytokine, and integrin receptor signaling. We show here that conditional mutation of Shp2 in neural crest cells and in myelinating Schwann cells resulted in deficits in glial development that are remarkably similar to those observed in mice mutant for Neuregulin-1 (Nrg1) or the Nrg1 receptors, ErbB2 and ErbB3. In cultured Shp2 mutant Schwann cells, Nrg1-evoked cellular responses like proliferation and migration were virtually abolished, and Nrg1-dependent intracellular signaling was altered. Pharmacological inhibition of Src family kinases mimicked all cellular and biochemical effects of the Shp2 mutation, implicating Src as a primary Shp2 target during Nrg1 signaling. Together, our genetic and biochemical analyses demonstrate that Shp2 is an essential component in the transduction of Nrg1/ErbB signals.
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27
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Lei H, Kazlauskas A. Growth factors outside of the platelet-derived growth factor (PDGF) family employ reactive oxygen species/Src family kinases to activate PDGF receptor alpha and thereby promote proliferation and survival of cells. J Biol Chem 2009; 284:6329-36. [PMID: 19126548 PMCID: PMC2649107 DOI: 10.1074/jbc.m808426200] [Citation(s) in RCA: 81] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2008] [Revised: 01/06/2009] [Indexed: 11/06/2022] Open
Abstract
The vitreous contains a plethora of growth factors that are strongly implicated in the formation of fibroproliferative diseases such as proliferative vitreoretinopathy. Although platelet-derived growth factors (PDGFs) are present in the vitreous, vitreal growth factors outside of the PDGF family activated the PDGF alpha receptor (PDGFRalpha) and promoted disease progression in a rabbit model of proliferative vitreoretinopathy (H. Lei, G. Velez, P. Hovland, T. Hirose, D. Gilbertson, and A. Kazlauskas (2008) submitted for publication.) In this report we investigated the mechanism by which non-PDGFs activated PDGFRalpha. We found that non-PDGFs increased the cellular level of reactive oxygen species (ROS) and that this event was necessary and sufficient for phosphorylation of PDGFRalpha. We speculated that the underlying mechanism was ROS-mediated inhibition of phosphotyrosine phosphatases, which antagonize receptor auto-phosphorylation. However, this did not appear to be the case. Non-PDGFs promoted tyrosine phosphorylation of catalytically inactive PDGFRalpha, and thereby indicated that at least one additional tyrosine kinase was involved. Indeed, preventing expression or blocking the kinase activity of Src family kinases suppressed non-PDGF-dependent tyrosine phosphorylation of PDGFRalpha. Thus non-PDGFs increased the level of ROS, which activated Src family kinases and resulted in phosphorylation of PDGFRalpha. Finally, although non-PDGFs induced only modest phosphorylation of PDGFRalpha, proliferation and survival of cells in response to non-PDGFs was significantly enhanced by expression of PDGFRalpha. These studies reveal a novel mechanism for activation of PDGFRalpha that appears capable of enhancing the responsiveness of cells to growth factors outside of the PDGF family.
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Affiliation(s)
- Hetian Lei
- Schepens Eye Research Institute, Department of Ophthalmology, Harvard Medical School, Boston, Massachusetts 02114, USA
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28
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Zhou X, Agazie YM. Molecular mechanism for SHP2 in promoting HER2-induced signaling and transformation. J Biol Chem 2009; 284:12226-34. [PMID: 19261604 DOI: 10.1074/jbc.m900020200] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The Src homology phosphotyrosyl phosphatase 2 (SHP2) plays a positive role in HER2-induced signaling and transformation, but its mechanism of action is poorly understood. Given the significance of HER2 in breast cancer, defining a mechanism for SHP2 in the HER2 signaling pathway is of paramount importance. In the current report we show that SHP2 positively modulates the Ras-extracellular signal-regulated kinase 1 and 2 and the phospoinositide-3-kinase-Akt pathways downstream of HER2 by increasing the half-life the activated form of Ras. This is accomplished by dephosphorylating an autophosphorylation site on HER2 that serves as a docking platform for the SH2 domains of the Ras GTPase-activating protein (RasGAP). The net effect is an increase in the intensity and duration of GTP-Ras levels with the overall impact of enhanced HER2 signaling and cell transformation. In conformity to these findings, the HER2 mutant that lacks the SHP2 target site exhibits an enhanced signaling and cell transformation potential. Therefore, SHP2 promotes HER2-induced signaling and transformation at least in part by dephosphorylating a negative regulatory autophosphorylation site. These results suggest that SHP2 might serve as a therapeutic target against breast cancer and other cancers characterized by HER2 overexpression.
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Affiliation(s)
- Xiangdong Zhou
- Department of Biochemistry and The Marry Babb Randolph Cancer Center, West Virginia University, Morgantown, West Virginia 26506, USA
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Cai X, Wu JH, Exum ST, Oppermann M, Premont RT, Shenoy SK, Freedman NJ. Reciprocal regulation of the platelet-derived growth factor receptor-beta and G protein-coupled receptor kinase 5 by cross-phosphorylation: effects on catalysis. Mol Pharmacol 2008; 75:626-36. [PMID: 19092051 DOI: 10.1124/mol.108.050278] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Signaling by the platelet-derived growth factor receptor-beta (PDGFRbeta) is diminished when the PDGFRbeta is phosphorylated on seryl residues by G protein-coupled receptor kinase-5 (GRK5), but mechanisms for GRK5 activation by the PDGFRbeta remain obscure. We therefore tested whether the PDGFRbeta is able to tyrosine-phosphorylate and thereby activate GRK5. Purified GRK5 was tyrosine-phosphorylated by the wild-type PDGFRbeta to a stoichiometry of 0.8 mol phosphate/mol GRK5, an extent approximately 5 times greater than observed with a Y857F PDGFRbeta mutant that fails to phosphorylate exogenous substrates but autophosphorylates and activates Src normally. The degree of PDGFRbeta-mediated phosphorylation of GRK5 correlated with GRK5 activity, as assessed by seryl phosphorylation of the PDGFRbeta in purified protein preparations, in intact cells expressing a tyrosine-to-phenylalanine GRK5 mutant, and in GRK5 peptide phosphorylation assays. However, tyrosyl phosphorylation of GRK5 was not necessary for GRK5-mediated phosphorylation of the beta(2)-adrenergic receptor, even though beta(2)-adrenergic receptor activation promoted tyrosyl phosphorylation of GRK5 in smooth muscle cells. Phosphorylation of the PDGFRbeta by GRK5 in smooth muscle cells or in purified protein preparations reduced PDGFRbeta-mediated peptide phosphorylation. In contrast, phosphorylation of GRK5 by the PDGFRbeta enhanced the V(max) of GRK5-mediated peptide phosphorylation, by 3.4-fold, without altering the GRK5 K(M) for peptide. We conclude that GRK5 tyrosyl phosphorylation is required for the activation of GRK5 by the PDGFRbeta, but not by the beta(2)-adrenergic receptor, and that by activating GRK5, the PDGFRbeta triggers its own desensitization.
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Affiliation(s)
- Xinjiang Cai
- Departments of Medicine/Cardiology, Duke University Medical Center, Durham, North Carolina, USA
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Abstract
Diverse cellular processes are regulated by tyrosyl phosphorylation, which is controlled by protein-tyrosine kinases (PTKs) and protein-tyrosine phosphatases (PTPs). De-regulated tyrosyl phosphorylation, evoked by gain-of-function mutations and/or over-expression of PTKs, contributes to the pathogenesis of many cancers and other human diseases. PTPs, because they oppose the action of PTKs, had been considered to be prime suspects for potential tumor suppressor genes. Surprisingly, few, if any, tumor suppressor PTPs have been identified. However, the Src homology-2 domain-containing phosphatase Shp2 (encoded by PTPN11) is a bona fide proto-oncogene. Germline mutations in PTPN11 cause Noonan and LEOPARD syndromes, whereas somatic PTPN11 mutations occur in several types of hematologic malignancies, most notably juvenile myelomonocytic leukemia and, more rarely, in solid tumors. Shp2 also is an essential component in several other oncogene signaling pathways. Elucidation of the events underlying Shp2-evoked transformation may provide new insights into oncogenic mechanisms and novel targets for anti-cancer therapy.
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Specific inhibitors of the protein tyrosine phosphatase Shp2 identified by high-throughput docking. Proc Natl Acad Sci U S A 2008; 105:7275-80. [PMID: 18480264 DOI: 10.1073/pnas.0710468105] [Citation(s) in RCA: 161] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The protein tyrosine phosphatase Shp2 is a positive regulator of growth factor signaling. Gain-of-function mutations in several types of leukemia define Shp2 as a bona fide oncogene. We performed a high-throughput in silico screen for small-molecular-weight compounds that bind the catalytic site of Shp2. We have identified the phenylhydrazonopyrazolone sulfonate PHPS1 as a potent and cell-permeable inhibitor, which is specific for Shp2 over the closely related tyrosine phosphatases Shp1 and PTP1B. PHPS1 inhibits Shp2-dependent cellular events such as hepatocyte growth factor/scatter factor (HGF/SF)-induced epithelial cell scattering and branching morphogenesis. PHPS1 also blocks Shp2-dependent downstream signaling, namely HGF/SF-induced sustained phosphorylation of the Erk1/2 MAP kinases and dephosphorylation of paxillin. Furthermore, PHPS1 efficiently inhibits activation of Erk1/2 by the leukemia-associated Shp2 mutant, Shp2-E76K, and blocks the anchorage-independent growth of a variety of human tumor cell lines. The PHPS compound class is therefore suitable for further development of therapeutics for the treatment of Shp2-dependent diseases.
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Betts GN, van der Geer P, Komives EA. Structural and functional consequences of tyrosine phosphorylation in the LRP1 cytoplasmic domain. J Biol Chem 2008; 283:15656-64. [PMID: 18381291 DOI: 10.1074/jbc.m709514200] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The cytoplasmic domain of LRP1 contains two NPXY motifs that have been shown to interact with signaling proteins. In previous work, we showed that Tyr(4507) in the distal NPXY motif is phosphorylated by v-Src, whereas denaturation of the protein was required for phosphorylation of Tyr(4473) in the membraneproximal NPXY motif. Amide H/D exchange studies reveal that the distal NPXY motif is fully solvent-exposed, whereas the proximal one is not. Phosphopeptide mapping combined with in vitro and in vivo kinase experiments show that Tyr(4473) can be phosphorylated, but only if Tyr(4507) is phosphorylated or substituted with glutamic acid. Amide H/D exchange experiments indicate that solvent accessibility increases across the entire LRP1 cytoplasmic region upon phosphorylation at Tyr(4507); in particular the NPXY(4473) motif becomes much more exposed. This differential phosphorylation is functionally relevant: binding of Snx17, which is known to bind at the proximal NPXY motif, is inhibited by phosphorylation at Tyr(4473). Conversely, Shp2 binds most strongly when both of the NPXY motifs in LRP1 are phosphorylated.
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Affiliation(s)
- Gina N Betts
- Department of Chemistry and Biochemistry, University of California, San Diego, La Jolla, California 92093-0378, USA
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33
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Abstract
Signals received at the cell surface must be properly transmitted to critical targets within the cell to achieve the appropriate biological response. This process of signal transduction is often initiated by receptor tyrosine kinases (RTKs), which function as entry points for many extracellular cues and play a critical role in recruiting the intracellular signaling cascades that orchestrate a particular response. Essential for most RTK-mediated signaling is the engagement and activation of the mitogen-activated protein kinase (MAPK) cascade comprised of the Raf, MEK and extracellular signal-regulated kinase (ERK) kinases. For many years, it was thought that signaling from RTKs to ERK occurred only at the plasma membrane and was mediated by a simple, linear Ras-dependent pathway. However, the limitation of this model became apparent with the discovery that Ras and ERK can be activated at various intracellular compartments, and that RTKs can modulate Ras/ERK signaling from these sites. Moreover, ERK scaffolding proteins and signaling modulators have been identified that play critical roles in determining the strength, duration and location of RTK-mediated ERK signaling. Together, these factors contribute to the diversity of biological responses generated by RTK signaling.
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Affiliation(s)
- M M McKay
- Laboratory of Cell and Developmental Signaling, NCI-Frederick, Frederick, MD 21702, USA
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34
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Mitchell D, O'Meara SJ, Gaffney A, Crean JKG, Kinsella BT, Godson C. The Lipoxin A4 receptor is coupled to SHP-2 activation: implications for regulation of receptor tyrosine kinases. J Biol Chem 2007; 282:15606-18. [PMID: 17403678 DOI: 10.1074/jbc.m611004200] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Mesangial cell proliferation is pivotal to the pathology of glomerular injury in inflammation. We have previously reported that lipoxins, endogenously produced eicosanoids with anti-inflammatory and pro-resolution bioactions, can inhibit mesangial cell proliferation in response to several agents. This process is associated with elaborate receptor cross-talk involving modification receptor tyrosine kinase phosphorylation (McMahon, B., Mitchell, D., Shattock, R., Martin, F., Brady, H. R., and Godson, C. (2002) FASEB J. 16, 1817-1819). Here we demonstrate that the lipoxin A(4) (LXA(4)) receptor is coupled to activation and recruitment of the SHP-2 (SH2 domain-containing tyrosine phosphatase-2) within a lipid raft microdomain. Using site-directed mutagenesis of the cytosolic domain of the platelet-derived growth factor receptor beta (PDGFRbeta), we report that mutation of the sites for phosphatidylinositol 3-kinase (Tyr(740) and Tyr(751)) and SHP-2 (Tyr(763) and Tyr(1009)) recruitment specifically inhibit the effect of LXA(4) on the PDGFRbeta signaling; furthermore inhibition of SHP-2 expression with short interfering RNA constructs blocked the effect of LXA(4) on PDGFRbeta phosphorylation. We demonstrate that association of the PDGFRbeta with lipid raft microdomains renders it susceptible to LXA(4)-mediated dephosphorylation by possible reactivation of oxidatively inactivated SHP-2. These data further elaborate on the potential mechanisms underlying the anti-inflammatory, proresolution, and anti-fibrotic bioactions of lipoxins.
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MESH Headings
- Cell Line
- Cell Proliferation
- Glomerular Mesangium/enzymology
- Glomerular Mesangium/injuries
- Humans
- Inflammation/enzymology
- Intracellular Signaling Peptides and Proteins/genetics
- Intracellular Signaling Peptides and Proteins/metabolism
- Membrane Microdomains/enzymology
- Membrane Microdomains/genetics
- Mutagenesis, Site-Directed
- Phosphatidylinositol 3-Kinases/genetics
- Phosphatidylinositol 3-Kinases/metabolism
- Phosphorylation
- Protein Phosphatase 2
- Protein Processing, Post-Translational/genetics
- Protein Structure, Tertiary/genetics
- Protein Tyrosine Phosphatase, Non-Receptor Type 11
- Protein Tyrosine Phosphatases/genetics
- Protein Tyrosine Phosphatases/metabolism
- Receptor, Platelet-Derived Growth Factor beta/genetics
- Receptor, Platelet-Derived Growth Factor beta/metabolism
- Receptors, Formyl Peptide/genetics
- Receptors, Formyl Peptide/metabolism
- Receptors, Lipoxin/genetics
- Receptors, Lipoxin/metabolism
- SH2 Domain-Containing Protein Tyrosine Phosphatases
- Signal Transduction/genetics
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Affiliation(s)
- Derick Mitchell
- School of Medicine and Medical Science, Diabetes Research Centre, UCD Conway Institute, University College Dublin, Belfield, Dublin 4, Ireland
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35
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Abstract
Ras genes are the most common targets for somatic gain-of-function mutations in human cancer. Recently, germline mutations that affect components of the Ras-Raf-mitogen-activated and extracellular-signal regulated kinase kinase (MEK)-extracellular signal-regulated kinase (ERK) pathway were shown to cause several developmental disorders, including Noonan, Costello and cardio-facio-cutaneous syndromes. Many of these mutant alleles encode proteins with aberrant biochemical and functional properties. Here we will discuss the implications of germline mutations in the Ras-Raf-MEK-ERK pathway for understanding normal developmental processes and cancer pathogenesis.
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Affiliation(s)
- Suzanne Schubbert
- Department of Pediatrics, University of California, 513 Parnassus Avenue, Room HSE-302, San Francisco, California 94143, USA
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36
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Abstract
It is now well established that the members of the PTP (protein tyrosine phosphatase) superfamily play critical roles in fundamental biological processes. Although there has been much progress in defining the function of PTPs, the task of identifying substrates for these enzymes still presents a challenge. Many PTPs have yet to have their physiological substrates identified. The focus of this review will be on the current state of knowledge of PTP substrates and the approaches used to identify them. We propose experimental criteria that should be satisfied in order to rigorously assign PTP substrates as bona fide. Finally, the progress that has been made in defining the biological roles of PTPs through the identification of their substrates will be discussed.
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Affiliation(s)
- Tony Tiganis
- *Department of Biochemistry and Molecular Biology, Monash University, Victoria 3800, Australia
| | - Anton M. Bennett
- †Department of Pharmacology, Yale University School of Medicine, New Haven, CT 06520, U.S.A
- To whom correspondence should be addressed (email )
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37
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Barua D, Faeder JR, Haugh JM. Structure-based kinetic models of modular signaling protein function: focus on Shp2. Biophys J 2007; 92:2290-300. [PMID: 17208977 PMCID: PMC1864834 DOI: 10.1529/biophysj.106.093484] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
We present here a computational, rule-based model to study the function of the SH2 domain-containing protein tyrosine phosphatase, Shp2, in intracellular signal transduction. The two SH2 domains of Shp2 differentially regulate the enzymatic activity by a well-characterized mechanism, but they also affect the targeting of Shp2 to signaling receptors in cells. Our kinetic model integrates these potentially competing effects by considering the intra- and intermolecular interactions of the Shp2 SH2 domains and catalytic site as well as the effect of Shp2 phosphorylation. Even for the isolated Shp2/receptor system, which may seem simple by certain standards, we find that the network of possible binding and phosphorylation states is composed of over 1000 members. To our knowledge, this is the first kinetic model to fully consider the modular, multifunctional structure of a signaling protein, and the computational approach should be generally applicable to other complex intermolecular interactions.
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Affiliation(s)
- Dipak Barua
- Department of Chemical and Biomolecular Engineering, North Carolina State University, Raleigh, North Carolina 27695, USA
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38
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Abstract
Signaling through platelet-derived growth factor (PDGF) receptors contributes to multiple tumor-associated processes. The recent introduction of clinically useful PDGF inhibitors have the last years validated PDGF receptors in malignant and stromal cells as relevant cancer drug targets. Mutational activation of PDGF receptor signaling in malignant cells has been described in some rare tumor types such as dermatofibrosarcoma protuberans, a subset of GISTs, and some hematologic malignancies. Furthermore, expression of PDGF receptors on pericytes is a common characteristic of solid tumors. The clinical efficacy of novel multikinase inhibitors, such as sunitinib and sorafenib, most likely involves targeting of PDGF receptor-dependent pericytes. Preclinical studies suggest that targeting of stromal PDGF receptors might also constitute a novel strategy to enhance tumor drug uptake. Finally, recent studies have implied both pro- and antimetastatic effects of PDGF receptors on malignant and stromal cells. The studies on the roles of PDGF receptors in cancer signaling are thus presently in a dynamic phase where collaborations between oncologists, pathologists, and tumor biologists are predicted to be highly productive.
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Affiliation(s)
- Arne Ostman
- Department of Pathology-Oncology, Cancer Center Karolinska, Karolinska Institutet, R8:03, SE-171 76 Stockholm, Sweden
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39
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Yoo JC, Hayman MJ. HSP70 binds to SHP2 and has effects on the SHP2-related EGFR/GAB1 signaling pathway. Biochem Biophys Res Commun 2006; 351:979-85. [PMID: 17097051 PMCID: PMC1698467 DOI: 10.1016/j.bbrc.2006.10.152] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2006] [Accepted: 10/26/2006] [Indexed: 11/18/2022]
Abstract
The Src homology phosphotyrosyl phosphatase, SHP2, is a positive effector of EGFR signaling. However, the molecular mechanism and biological functions of SHP2 regulation are still not completely known. To better understand the cellular processes in which SHP2 participates, we carried out mass spectrometry to find SHP2 binding proteins. FLAG-SHP2 complexes were isolated by affinity purification, and associated proteins were identified by in-gel trypsin digestion followed by LC/MS/MS mass spectrometry. Among the identified proteins, we focus in this report on the heat shock protein 70 (HSP70). Physical interactions of SHP2 with HSP70 were confirmed in vivo. Further experiments demonstrate that EGF does not activate binding of SHP2 with HSP70 rather the binding appears to be constitutive. However, the formation of an HSP70/SHP2 complex affected the binding of SHP2 with EGFR and (or) GAB1. These data suggest that binding of HSP70 with SHP2 regulates to some extent the EGF signaling pathway. In addition, immunostaining experiments indicated that SHP2 and HSP70 co-localized in the cell membrane region after EGF treatment. Our findings propose a possible involvement of HSP70 in the regulation of EGF signaling pathway by SHP2.
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Affiliation(s)
- Jae Cheal Yoo
- Department of Molecular Genetics and Microbiology, Stony Brook University, Stony Brook, NY 11794-5222, USA
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40
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Wu JH, Goswami R, Cai X, Exum ST, Huang X, Zhang L, Brian L, Premont RT, Peppel K, Freedman NJ. Regulation of the platelet-derived growth factor receptor-beta by G protein-coupled receptor kinase-5 in vascular smooth muscle cells involves the phosphatase Shp2. J Biol Chem 2006; 281:37758-72. [PMID: 17018529 DOI: 10.1074/jbc.m605756200] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Smooth muscle cell (SMC) proliferation and migration are substantially controlled by the platelet-derived growth factor receptor-beta (PDGFRbeta), which can be regulated by the Ser/Thr kinase G protein-coupled receptor kinase-2 (GRK2). In mouse aortic SMCs, however, we found that prolonged PDGFRbeta activation engendered down-regulation of GRK5, but not GRK2; moreover, GRK5 and PDGFRbeta were coordinately up-regulated in SMCs from atherosclerotic arteries. With SMCs from GRK5 knock-out and cognate wild type mice (five of each), we found that physiologic expression of GRK5 increased PDGF-promoted PDGFRbeta seryl phosphorylation by 3-fold and reduced PDGFRbeta-promoted phosphoinositide hydrolysis, thymidine incorporation, and overall PDGFRbeta tyrosyl phosphorylation by approximately 35%. Physiologic SMC GRK5 activity also increased PDGFRbeta association with the phosphatase Shp2 (8-fold), enhanced phosphorylation of PDGFRbeta Tyr(1009) (the docking site for Shp2), and reduced phosphorylation of PDGFRbeta Tyr(1021). Consistent with having increased PDGFRbeta-associated Shp2 activity, GRK5-expressing SMCs demonstrated greater PDGF-induced Src activation than GRK5-null cells. GRK5-mediated desensitization of PDGFRbeta inositol phosphate signaling was diminished by Shp2 knock-down or impairment of PDGFRbeta/Shp2 association. In contrast to GRK5, physiologic GRK2 activity did not alter PDGFRbeta/Shp2 association. Finally, purified GRK5 effected agonist-dependent seryl phosphorylation of partially purified PDGFRbetas. We conclude that GRK5 mediates the preponderance of PDGF-promoted seryl phosphorylation of the PDGFRbeta in SMCs, and, through mechanisms involving Shp2, desensitizes PDGFRbeta inositol phosphate signaling and enhances PDGFRbeta-triggered Src activation.
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MESH Headings
- Animals
- Base Sequence
- Cattle
- Cell Movement
- Cell Proliferation
- Cells, Cultured
- DNA Primers/genetics
- G-Protein-Coupled Receptor Kinase 5
- Humans
- Intracellular Signaling Peptides and Proteins/genetics
- Intracellular Signaling Peptides and Proteins/metabolism
- Mice
- Mice, Inbred C57BL
- Mice, Knockout
- Models, Biological
- Muscle, Smooth, Vascular/cytology
- Muscle, Smooth, Vascular/metabolism
- Phosphorylation
- Protein Serine-Threonine Kinases/deficiency
- Protein Serine-Threonine Kinases/genetics
- Protein Serine-Threonine Kinases/metabolism
- Protein Tyrosine Phosphatase, Non-Receptor Type 11
- Protein Tyrosine Phosphatases/genetics
- Protein Tyrosine Phosphatases/metabolism
- RNA Interference
- Rabbits
- Receptor, Platelet-Derived Growth Factor beta/genetics
- Receptor, Platelet-Derived Growth Factor beta/metabolism
- Recombinant Proteins/genetics
- Recombinant Proteins/metabolism
- Transfection
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Affiliation(s)
- Jiao-Hui Wu
- Department of Medicine (Cardiology), Duke University, Medical Center, Durham, North Carolina 27710, USA
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41
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Fornaro M, Burch PM, Yang W, Zhang L, Hamilton CE, Kim JH, Neel BG, Bennett AM. SHP-2 activates signaling of the nuclear factor of activated T cells to promote skeletal muscle growth. ACTA ACUST UNITED AC 2006; 175:87-97. [PMID: 17015617 PMCID: PMC2064501 DOI: 10.1083/jcb.200602029] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The formation of multinucleated myofibers is essential for the growth of skeletal muscle. The nuclear factor of activated T cells (NFAT) promotes skeletal muscle growth. How NFAT responds to changes in extracellular cues to regulate skeletal muscle growth remains to be fully defined. In this study, we demonstrate that mice containing a skeletal muscle-specific deletion of the tyrosine phosphatase SHP-2 (muscle creatine kinase [MCK]-SHP-2 null) exhibited a reduction in both myofiber size and type I slow myofiber number. We found that interleukin-4, an NFAT-regulated cytokine known to stimulate myofiber growth, was reduced in its expression in skeletal muscles of MCK-SHP-2-null mice. When SHP-2 was deleted during the differentiation of primary myoblasts, NFAT transcriptional activity and myotube multinucleation were impaired. Finally, SHP-2 coupled myotube multinucleation to an integrin-dependent pathway and activated NFAT by stimulating c-Src. Thus, SHP-2 transduces extracellular matrix stimuli to intracellular signaling pathways to promote skeletal muscle growth.
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Affiliation(s)
- Mara Fornaro
- Department of Pharmacology, Yale University School of Medicine, New Haven, CT 06520, USA
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42
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Heiss E, Masson K, Sundberg C, Pedersen M, Sun J, Bengtsson S, Rönnstrand L. Identification of Y589 and Y599 in the juxtamembrane domain of Flt3 as ligand-induced autophosphorylation sites involved in binding of Src family kinases and the protein tyrosine phosphatase SHP2. Blood 2006; 108:1542-50. [PMID: 16684964 DOI: 10.1182/blood-2005-07-008896] [Citation(s) in RCA: 56] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Early signal relay steps upon ligand binding to the receptor tyrosine kinase Flt3 (ie, sites of Flt3 autophosphorylation and subsequent docking partners) are mainly unresolved. By immunoprecipitation of specific tryptic peptides contained in the juxtamembrane region of human Flt3 and subsequent radiosequencing, we identified the tyrosine residues 572, 589, 591, and 599 as in vivo autophosphorylation sites. Focusing on Y589 and Y599, we examined Flt3 ligand (FL)-mediated responses in wild-type-Flt3-(WT-Flt3-), Y589F-Flt3-, and Y599F-Flt3-expressing 32D cells. Compared with WT-Flt3-32D cells upon ligand stimulation, 32D-Y589F-Flt3 showed enhanced Erk activation and proliferation/survival, whereas 32D-Y599F-Flt3 cells hereby displayed substantially diminished responses. Both pY589 and pY599 were identified as association sites for signal relay molecules including Src family kinases and SHP2. Consistently, 32D-Y589F-Flt3 and 32D-Y599F-Flt3 showed decreased FL-triggered activation of Src family kinases. Interference with the Src-dependent negative regulation of Flt3 signaling may account for the enhanced mitogenic response of Y589F-Flt3. Y599 was additionally found to interact with the protein tyrosine phosphatase SHP2 in a phosphorylation-dependent manner. As Y599F-Flt3-32D was unable to associate with and to phosphorylate SHP2 and since silencing of SHP2 in WT-Flt3-expressing cells mimicked the Y599F-Flt3 phenotype, we hypothesize that recruitment of SHP2 to pY599 contributes to FL-mediated Erk activation and proliferation.
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Affiliation(s)
- Elke Heiss
- Experimental Clinical Chemistry, Department of Laboratory Medicine, Lund University, Malmö University Hospital, Malmö, Sweden
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43
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Yang W, Klaman LD, Chen B, Araki T, Harada H, Thomas SM, George EL, Neel BG. An Shp2/SFK/Ras/Erk signaling pathway controls trophoblast stem cell survival. Dev Cell 2006; 10:317-27. [PMID: 16516835 DOI: 10.1016/j.devcel.2006.01.002] [Citation(s) in RCA: 191] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2005] [Revised: 12/28/2005] [Accepted: 01/05/2006] [Indexed: 11/18/2022]
Abstract
Little is known about how growth factors control tissue stem cell survival and proliferation. We analyzed mice with a null mutation of Shp2 (Ptpn11), a key component of receptor tyrosine kinase signaling. Null embryos die peri-implantation, much earlier than mice that express an Shp2 truncation. Shp2 null blastocysts initially develop normally, but they subsequently exhibit inner cell mass death, diminished numbers of trophoblast giant cells, and failure to yield trophoblast stem (TS) cell lines. Molecular markers reveal that the trophoblast lineage, which requires fibroblast growth factor-4 (FGF4), is specified but fails to expand normally. Moreover, deletion of Shp2 in TS cells causes rapid apoptosis. We show that Shp2 is required for FGF4-evoked activation of the Src/Ras/Erk pathway that culminates in phosphorylation and destabilization of the proapoptotic protein Bim. Bim depletion substantially blocks apoptosis and significantly restores Shp2 null TS cell proliferation, thereby establishing a key mechanism by which FGF4 controls stem cell survival.
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Affiliation(s)
- Wentian Yang
- Cancer Biology Program, Division of Hematology/Oncology, Department of Medicine, Beth Israel Deaconess Medical Center, Boston, Massachusetts 02115, USA.
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44
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Abstract
Tyrosine phosphorylation is an important signalling mechanism in eukaryotic cells. In cancer, oncogenic activation of tyrosine kinases is a common feature, and novel anticancer drugs have been introduced that target these enzymes. Tyrosine phosphorylation is also controlled by protein-tyrosine phosphatases (PTPs). Recent evidence has shown that PTPs can function as tumour suppressors. In addition, some PTPs, including SHP2, positively regulate the signalling of growth-factor receptors, and can be oncogenic. An improved understanding of how these enzymes function and how they are regulated might aid the development of new anticancer agents.
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Affiliation(s)
- Arne Ostman
- Cancer Center Karolinska, Department of Pathology and Oncology, Karolinska Institutet, Stockholm, Sweden
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45
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Oishi K, Gaengel K, Krishnamoorthy S, Kamiya K, Kim IK, Ying H, Weber U, Perkins LA, Tartaglia M, Mlodzik M, Pick L, Gelb BD. Transgenic Drosophila models of Noonan syndrome causing PTPN11 gain-of-function mutations. Hum Mol Genet 2006; 15:543-53. [PMID: 16399795 DOI: 10.1093/hmg/ddi471] [Citation(s) in RCA: 56] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Mutations in the PTPN11 gene, which encodes the protein tyrosine phosphatase SHP-2, causes Noonan syndrome (NS), an autosomal dominant disorder with pleomorphic developmental abnormalities. Certain germline and somatic PTPN11 mutations cause leukemias. Mutations have gain-of-function (GOF) effects with the commonest NS allele, N308D, being weaker than the leukemia-causing mutations. To study the effects of disease-associated PTPN11 alleles, we generated transgenic fruitflies with GAL4-inducible expression of wild-type or mutant csw, the Drosophila orthologue of PTPN11. All three transgenic mutant CSWs rescued a hypomorphic csw allele's eye phenotype, documenting activity. Ubiquitous expression of two strong csw mutant alleles were lethal, but did not perturb development from some CSW-dependent receptor tyrosine kinase pathways. Ubiquitous expression of the weaker N308D allele caused ectopic wing veins, identical to the EGFR GOF phenotype. Epistatic analyses established that csw(N308D)'s ectopic wing vein phenotype required intact EGF ligand and receptor, and that this transgene interacted genetically with Notch, DPP and JAK/STAT signaling. Expression of the mutant csw transgenes increased RAS-MAP kinase activation, which was necessary but not sufficient for transducing their phenotypes. The findings from these fly models provided hypotheses testable in mammalian models, in which these signaling cassettes are largely conserved. In addition, these fly models can be used for sensitized screens to identify novel interacting genes as well as for high-throughput screening of therapeutic compounds for NS and PTPN11-related cancers.
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Affiliation(s)
- Kimihiko Oishi
- Departments of Pediatrics and Human Genetics, Mount Sinai School of Medicine, One Gustave L. Levy Place, Box 1498, New York, NY 10029, USA
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46
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Abstract
Tolerance of natural killer (NK) cells toward normal cells is mediated through their expression of inhibitory receptors that detect the normal expression of self in the form of class I major histocompatibility complex (MHC-I) molecules on target cells. These MHC-I-binding inhibitory receptors recruit tyrosine phosphatases, which are believed to counteract activating receptor-stimulated tyrosine kinases. The perpetual balance between signals derived from inhibitory and activating receptors controls NK cell responsiveness and provides an interesting paradigm of signaling cross talk. This review summarizes our knowledge of the intracellular mechanisms by which cell surface receptors influence biological responses by NK cells. Special emphasis focuses on the dynamic signaling events at the NK immune synapse and the unique signaling characteristics of specific receptors, such as NKG2D, 2B4, and KIR2DL4.
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Affiliation(s)
- A W MacFarlane
- Fox Chase Cancer Center, Division of Basic Science, Institute for Cancer Research, 333 Cottman Ave., Philadelphia, PA 19111, USA
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47
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Mitola S, Brenchio B, Piccinini M, Tertoolen L, Zammataro L, Breier G, Rinaudo MT, den Hertog J, Arese M, Bussolino F. Type I collagen limits VEGFR-2 signaling by a SHP2 protein-tyrosine phosphatase-dependent mechanism 1. Circ Res 2005; 98:45-54. [PMID: 16339483 DOI: 10.1161/01.res.0000199355.32422.7b] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
During angiogenesis, a combined action between newly secreted extracellular matrix proteins and the repertoire of integrins expressed by endothelial cells contributes in the regulation of their biological functions. Extracellular matrix-engaged integrins influence tyrosine kinase receptors, thus promoting a regulatory cross-talk between adhesive and soluble stimuli. For instance, vitronectin has been reported to positively regulate VEGFR-2. Here, we show that collagen I downregulates VEGF-A-mediated VEGFR-2 activation. This activity requires the tyrosine phosphatase SHP2, which is recruited to the activated VEGFR-2 when cells are plated on collagen I, but not on vitronectin. Constitutive expression of SHP2(C459S) mutant inhibits the negative role of collagen I on VEGFR-2 phosphorylation. VEGFR-2 undergoes internalisation, which is associated with dynamin II phosphorylation. Expression of SHP2(C459S) impairs receptor internalisation suggesting that SHP2-dependent dephosphorylation regulates this process. These findings demonstrate that collagen I in provisional extracellular matrix surrounding nascent capillaries triggers a signaling pathway that negatively regulates angiogenesis.
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Affiliation(s)
- Stefania Mitola
- Institute for Cancer Research and Treatment, Department of Oncological Sciences, University of Torino, Turin, Italy
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48
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Chen KT, Lin JD, Liou MJ, Weng HF, Chang CA, Chan EC. An aberrant autocrine activation of the platelet-derived growth factor alpha-receptor in follicular and papillary thyroid carcinoma cell lines. Cancer Lett 2005; 231:192-205. [PMID: 16126335 DOI: 10.1016/j.canlet.2005.01.039] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2004] [Revised: 01/30/2005] [Accepted: 01/31/2005] [Indexed: 10/25/2022]
Abstract
Platelet-derived growth factor receptor (PDGFR) can bind to its ligand and consequently possess a kinase activity, and which is associated with the carcinogenesis of different cell types, including astrocytomas, oligodendrogliomas, and glioblastoma. In a cDNA microarray analysis, we observe the over-expressed mRNA of both PDGF-A and PDGF-alpha receptor in thyroid carcinoma cells. And the elevated protein expressions of PDGF-A and PDGF-alpha receptor in thyroid carcinoma cells were also confirmed by a Western blot analysis. The phosphorylation of PDGF-alpha receptor evaluated by an antibody against Tyr 720-phosphate was found in thyroid carcinoma cells. The tyrosine kinase activity of PDGF-alpha receptor was inhibited by tyrphostin AG1295 and showed a dose-dependent inhibition for the proliferation of thyroid carcinoma cells. These findings imply that autocrine activation of PDGF-alpha receptor plays a crucial role in the carcinogenesis of thyroid cells.
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MESH Headings
- Adenocarcinoma, Follicular/genetics
- Adenocarcinoma, Follicular/metabolism
- Adenocarcinoma, Papillary/genetics
- Adenocarcinoma, Papillary/metabolism
- Autocrine Communication
- Blotting, Western
- Cell Proliferation/drug effects
- DNA, Complementary
- Enzyme Activation
- Gene Expression Profiling
- Humans
- Oligonucleotide Array Sequence Analysis
- Phosphorylation
- Platelet-Derived Growth Factor/genetics
- Platelet-Derived Growth Factor/metabolism
- RNA, Messenger/genetics
- RNA, Messenger/metabolism
- Receptor, Platelet-Derived Growth Factor alpha/genetics
- Receptor, Platelet-Derived Growth Factor alpha/metabolism
- Thyroid Neoplasms/genetics
- Thyroid Neoplasms/metabolism
- Tumor Cells, Cultured
- Tyrosine/metabolism
- Tyrphostins/pharmacology
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Affiliation(s)
- Kuei-Tien Chen
- School of Medical Technology, Chang Gung University, Taoyuan, Taiwan
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Bourdeau A, Dubé N, Tremblay ML. Cytoplasmic protein tyrosine phosphatases, regulation and function: the roles of PTP1B and TC-PTP. Curr Opin Cell Biol 2005; 17:203-9. [PMID: 15780598 DOI: 10.1016/j.ceb.2005.02.001] [Citation(s) in RCA: 171] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
PTP1B and TC-PTP are closely related protein tyrosine phosphatases, sharing 74% homology in their catalytic domain. However, their cellular localization, function, and regulation are found to be different. Their substrate specificity has implicated these enzymes in various signaling pathways, regulating metabolism, proliferation and cytokine signaling. For instance, PTP1B has been shown to regulate the activation of cytokine receptors through the dephosphorylation of specific members of the JAK family, namely JAK2 and TYK2, whereas TC-PTP is involved in the modulation of cytokine signaling via JAK1 and JAK3 molecules. Gene-targeting approaches will help us to unravel the physiological functions of these enzymes.
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Affiliation(s)
- Annie Bourdeau
- McGill Cancer Centre, McGill University, 3655 Promenade Sir-William-Osler, room 701, Montreal, QC, H3G 1Y6, Canada
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Takahashi K, Kogaki S, Kurotobi S, Nasuno S, Ohta M, Okabe H, Wada K, Sakai N, Taniike M, Ozono K. A novel mutation in the PTPN11 gene in a patient with Noonan syndrome and rapidly progressive hypertrophic cardiomyopathy. Eur J Pediatr 2005; 164:497-500. [PMID: 15889278 DOI: 10.1007/s00431-005-1679-y] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/03/2004] [Revised: 03/17/2005] [Accepted: 03/18/2005] [Indexed: 10/25/2022]
Abstract
UNLABELLED A male infant with clinical features of Noonan syndrome and rapidly progressive hypertrophic cardiomyopathy is reported. He manifested severe heart failure and failure to thrive. Administration of propranolol and cibenzoline improved ventricular outflow tract obstruction, leading to catch-up growth. Genetic analysis of the patient revealed a novel missense mutation in the PTPN11 gene. CONCLUSION This is the first description of a patient with a Gln510Glu mutation in the protein-tyrosine phosphatase, non-receptor type 11 gene. This specific mutation may be associated with a rapidly progressive hypertrophic cardiomyopathy.
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Affiliation(s)
- Kunihiko Takahashi
- Department of Developmental Medicine (Paediatrics), Osaka University Graduate School of Medicine, 2-2 Yamada-oka, 565-0871 Suita, Osaka, Japan
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