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Structural Insights into the Binding Propensity of Human SHIP2 SH2 to Oncogenic CagA Isoforms from Helicobacter pylori. Int J Mol Sci 2022; 23:ijms231911299. [PMID: 36232599 PMCID: PMC9569640 DOI: 10.3390/ijms231911299] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2022] [Revised: 09/20/2022] [Accepted: 09/20/2022] [Indexed: 11/30/2022] Open
Abstract
SHIP2 is a multi-domain inositol 5-phosphatase binding to a variety of phosphotyrosine (pY)-containing proteins through its SH2 domain, so as to regulate various cell signaling pathways by modulating the phosphatidylinositol level in the plasma membrane. Unfavorably, Helicobacter pylori can hijack SHIP2 through the CagA protein to induce gastric cell carcinogenesis. To date, the interaction between SHIP2 and CagA was not analyzed from a structural point of view. Here, the binding of SHIP2-SH2 with Tyr-phosphorylated peptides from four EPIYA motifs (A/B/C/D) in CagA was studied using NMR spectroscopy. The results showed that EPIYA-C and -D bind to a similar interface of SHIP2-SH2, including a pY-binding pocket and a hydrophobic pocket, to achieve high affinity, while EPIYA-A and -B bind to a smaller interface of SHIP2-SH2 with weak affinity. By summarizing the interface and affinity of SHIP2-SH2 for CagA EPIYA-A/B/C/D, c-MET and FcgR2B ITIM, it was proposed that, potentially, SHIP2-SH2 has a selective preference for L > I > V for the aliphatic residues at the pY+3 position in its ligand. This study reveals the rule of the ligand sequence bound by SHIP2-SH2 and the mechanism by which CagA protein hijacks SHIP2, which will help design a peptide inhibitor against SHIP2-SH2.
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Wang Z, Zhou H, Yue X, Zhu J, Yang Y, Liu M. An auxiliary binding interface of SHIP2-SH2 for Y292-phosphorylated FcγRIIB reveals diverse recognition mechanisms for tyrosine-phosphorylated receptors involved in different cell signaling pathways. Anal Bioanal Chem 2021; 414:497-506. [PMID: 34021368 DOI: 10.1007/s00216-021-03373-w] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2021] [Revised: 04/16/2021] [Accepted: 04/23/2021] [Indexed: 12/27/2022]
Abstract
SH2 domain-containing inositol 5-phosphatase 2 (SHIP2) plays an essential role in regulating phosphatidylinositol level in human cell, and is recruited to many phosphotyrosine (pY)-dependent signal transduction pathways by the SH2 domain. In immunity signaling, immunoreceptor FcγRIIB binds to SHIP2-SH2 via its Y292-phosphorylated immunoreceptor tyrosine-based inhibitory motif (ITIM) and transmits inhibitory signal, which regulates B cell and neuronal cell activity and is associated with immune diseases and Alzheimer's disease. To date, the interaction between SHIP2 and FcγRIIB has not been analyzed from a structural point of view. Here, the binding of SHIP2-SH2 with Y292-phosphorylated FcγRIIB-ITIM was analyzed using NMR spectroscopy. The results demonstrated that SHIP2-SH2 mainly utilizes two regions including a pY-binding pocket and a specificity pocket formed by βD, βE, and EF-loop, to bind with FcγRIIB-ITIM in high affinity. In addition to the two regions, the BG-loop of SHIP2-SH2 functions as an auxiliary interface enhancing affinity. By comparing the binding of SHIP2-SH2 with ligands from FcγRIIB and c-MET, a hepatocyte growth factor receptor associated with tumorigenesis, significant differences in interface and affinity were found, suggesting that SHIP2-SH2 applies diverse patterns for binding to different ligand proteins. Moreover, S49, S51, and R70 of SHIP2 were identified to mediate the binding of both FcγRIIB and c-MET, while R28 and Q107 were found to only participate in the binding of c-MET and FcγRIIB respectively. Taken together, this study reveals the diverse mechanisms of SHIP2-SH2 for recognizing different ligands, and provides important clues for selectively manipulating various signaling pathways and specific drug design.
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Affiliation(s)
- Zi Wang
- State Key Laboratory of Magnetic Resonance and Atomic Molecular Physics, Key Laboratory of Magnetic Resonance in Biological Systems, National Center for Magnetic Resonance in Wuhan, Wuhan Institute of Physics and Mathematics, Innovation Academy for Precision Measurement Science and Technology, Chinese Academy of Sciences - Wuhan National Laboratory for Optoelectronics, Wuhan, 430071, Hubei, China.,University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Heng Zhou
- State Key Laboratory of Magnetic Resonance and Atomic Molecular Physics, Key Laboratory of Magnetic Resonance in Biological Systems, National Center for Magnetic Resonance in Wuhan, Wuhan Institute of Physics and Mathematics, Innovation Academy for Precision Measurement Science and Technology, Chinese Academy of Sciences - Wuhan National Laboratory for Optoelectronics, Wuhan, 430071, Hubei, China.,Department of Chemistry, College of Science, Huazhong Agricultural University, Wuhan, 430070, Hubei, China
| | - Xiali Yue
- Department of Chemistry, College of Science, Huazhong Agricultural University, Wuhan, 430070, Hubei, China
| | - Jiang Zhu
- State Key Laboratory of Magnetic Resonance and Atomic Molecular Physics, Key Laboratory of Magnetic Resonance in Biological Systems, National Center for Magnetic Resonance in Wuhan, Wuhan Institute of Physics and Mathematics, Innovation Academy for Precision Measurement Science and Technology, Chinese Academy of Sciences - Wuhan National Laboratory for Optoelectronics, Wuhan, 430071, Hubei, China
| | - Yunhuang Yang
- State Key Laboratory of Magnetic Resonance and Atomic Molecular Physics, Key Laboratory of Magnetic Resonance in Biological Systems, National Center for Magnetic Resonance in Wuhan, Wuhan Institute of Physics and Mathematics, Innovation Academy for Precision Measurement Science and Technology, Chinese Academy of Sciences - Wuhan National Laboratory for Optoelectronics, Wuhan, 430071, Hubei, China. .,University of Chinese Academy of Sciences, Beijing, 100049, China.
| | - Maili Liu
- State Key Laboratory of Magnetic Resonance and Atomic Molecular Physics, Key Laboratory of Magnetic Resonance in Biological Systems, National Center for Magnetic Resonance in Wuhan, Wuhan Institute of Physics and Mathematics, Innovation Academy for Precision Measurement Science and Technology, Chinese Academy of Sciences - Wuhan National Laboratory for Optoelectronics, Wuhan, 430071, Hubei, China. .,University of Chinese Academy of Sciences, Beijing, 100049, China.
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Csolle MP, Ooms LM, Papa A, Mitchell CA. PTEN and Other PtdIns(3,4,5)P 3 Lipid Phosphatases in Breast Cancer. Int J Mol Sci 2020; 21:ijms21239189. [PMID: 33276499 PMCID: PMC7730566 DOI: 10.3390/ijms21239189] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2020] [Revised: 11/25/2020] [Accepted: 12/01/2020] [Indexed: 12/31/2022] Open
Abstract
The phosphoinositide 3-kinase (PI3K)/AKT signalling pathway is hyperactivated in ~70% of breast cancers. Class I PI3K generates PtdIns(3,4,5)P3 at the plasma membrane in response to growth factor stimulation, leading to AKT activation to drive cell proliferation, survival and migration. PTEN negatively regulates PI3K/AKT signalling by dephosphorylating PtdIns(3,4,5)P3 to form PtdIns(4,5)P2. PtdIns(3,4,5)P3 can also be hydrolysed by the inositol polyphosphate 5-phosphatases (5-phosphatases) to produce PtdIns(3,4)P2. Interestingly, while PTEN is a bona fide tumour suppressor and is frequently mutated/lost in breast cancer, 5-phosphatases such as PIPP, SHIP2 and SYNJ2, have demonstrated more diverse roles in regulating mammary tumourigenesis. Reduced PIPP expression is associated with triple negative breast cancers and reduced relapse-free and overall survival. Although PIPP depletion enhances AKT phosphorylation and supports tumour growth, this also inhibits cell migration and metastasis in vivo, in a breast cancer oncogene-driven murine model. Paradoxically, SHIP2 and SYNJ2 are increased in primary breast tumours, which correlates with invasive disease and reduced survival. SHIP2 or SYNJ2 overexpression promotes breast tumourigenesis via AKT-dependent and independent mechanisms. This review will discuss how PTEN, PIPP, SHIP2 and SYNJ2 distinctly regulate multiple functional targets, and the mechanisms by which dysregulation of these distinct phosphoinositide phosphatases differentially affect breast cancer progression.
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Azzi A. Scaffold dependent role of the inositol 5'-phosphatase SHIP2, in regulation of oxidative stress induced apoptosis. Arch Biochem Biophys 2020; 697:108667. [PMID: 33181128 DOI: 10.1016/j.abb.2020.108667] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2020] [Revised: 10/29/2020] [Accepted: 11/04/2020] [Indexed: 11/19/2022]
Abstract
Cell apoptosis is an important process that occurs during development or in response to stress stimuli such as oxidative stress. The serine-threonine kinase Akt enhances survival and suppress apoptosis. SHIP2 is known as a negative regulator of Akt. In addition to its lipid 5'-phosphatase activity, SHIP2 interacts and signals as a scaffolding complex with several proteins. Several findings have pointed out a possible role of SHIP2 in apoptosis regulation. However, the molecular mechanisms behind remain unknown. Using embryonic fibroblast lacking the lipid 5'-phosphatase domain as a genetic model system and human liver cancer cells treated with SHIP2 inhibitor (AS1949490), as a pharmacological model system. We provide the first evidence that SHIP2 regulates apoptosis independently of its 5'-phosphates activity. Indeed, absence of the 5'-phosphatase domain of SHIP2 did not prevent H2O2-induced apoptosis in fibroblasts. Whereas chemical inactivation or RNAi knockdown of SHIP2 blocked H2O2-induced apoptosis in HepG2 cells. We found that suppression of apoptosis upon SHIP2 inhibition is PI3K/Akt independent but rather MAP kinase dependent. In addition, we found that AS1949490 altered both 5'-phosphatase and scaffolding function of SHIP2. Indeed, AS1949490 mediated SHIP2 inhibition promotes protein complex formation of SHIP2 together with non-receptor tyrosine kinase SRC and ABL which in turn enhances PI3K/Akt and MAP kinase pathways activation. Dual inhibition of SRC/ABL blocked activation of both pathways upon SHIP2 inhibition and H2O2 treatment. Altogether, these findings indicate that SHIP2 protein play a determinant role in H2O2-induced apoptosis.
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Affiliation(s)
- Abdelhalim Azzi
- GIGA-Molecular Biology of Disease, GIGA-B34, Centre Hospitalier Universitaire Sart-Tilman, University of Liège, avenue de l'Hôpital 11, 4000, Liège, Belgium.
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Functional Genome-wide Screen Identifies Pathways Restricting Central Nervous System Axonal Regeneration. Cell Rep 2019; 23:415-428. [PMID: 29642001 DOI: 10.1016/j.celrep.2018.03.058] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2017] [Revised: 02/12/2018] [Accepted: 03/14/2018] [Indexed: 12/22/2022] Open
Abstract
Axonal regrowth is crucial for recovery from CNS injury but is severely restricted in adult mammals. We used a genome-wide loss-of-function screen for factors limiting axonal regeneration from cerebral cortical neurons in vitro. Knockdown of 16,007 individual genes identified 580 significant phenotypes. These molecules share no significant overlap with those suggested by previous expression profiles. There is enrichment for genes in pathways related to transport, receptor binding, and cytokine signaling, including Socs4 and Ship2. Among transport-regulating proteins, Rab GTPases are prominent. In vivo assessment with C. elegans validates a cell-autonomous restriction of regeneration by Rab27. Mice lacking Rab27b show enhanced retinal ganglion cell axon regeneration after optic nerve crush and greater motor function and raphespinal sprouting after spinal cord trauma. Thus, a comprehensive functional screen reveals multiple pathways restricting axonal regeneration and neurological recovery after injury.
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Li KN, Zhang YY, Yu YN, Wu HL, Wang Z. Met-Controlled Allosteric Module of Neural Generation as A New Therapeutic Target in Rodent Brain Ischemia. Chin J Integr Med 2019; 27:896-904. [PMID: 31418133 DOI: 10.1007/s11655-019-3182-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/05/2019] [Indexed: 11/30/2022]
Abstract
OBJECTIVE To investigate a Met-controlled allosteric module (AM) of neural generation as a potential therapeutic target for brain ischemia. METHODS We selected Markov clustering algorithm (MCL) to mine functional modules in the related target networks. According to the topological similarity, one functional module was predicted in the modules of baicalin (BA), jasminoidin (JA), cholic acid (CA), compared with I/R model modules. This functional module included three genes: Inppl1, Met and Dapk3 (IMD). By gene ontology enrichment analysis, biological process related to this functional module was obtained. This functional module participated in generation of neurons. Western blotting was applied to present the compound-dependent regulation of IMD. Co-immunoprecipitation was used to reveal the relationship among the three members. We used IF to determine the number of newborn neurons between compound treatment group and ischemia/reperfusion group. The expressions of vascular endothelial growth factor (VEGF) and matrix metalloproteinase 9 (MMP-9) were supposed to show the changing circumstances for neural generation under cerebral ischemia. RESULTS Significant reduction in infarction volume and pathological changes were shown in the compound treatment groups compared with the I/R model group (P<0.05). Three nodes in one novel module of IMD were found to exert diverse compound-dependent ischemic-specific excitatory regulatory activities. An anti-ischemic excitatory allosteric module (AME) of generation of neurons (AME-GN) was validated successfully in vivo. Newborn neurons increased in BJC treatment group (P<0.05). The expression of VEGF and MMP-9 decreased in the compound treatment groups compared with the I/R model group (P<0.05). CONCLUSIONS AME demonstrates effectiveness of our pioneering approach to the discovery of therapeutic target. The novel approach for AM discovery in an effort to identify therapeutic targets holds the promise of accelerating elucidation of underlying pharmacological mechanisms in cerebral ischemia.
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Affiliation(s)
- Kang-Ning Li
- Department of Traditional Chinese Medicine, Beijing Tiantan Hospital, Capital Medical University, Beijing, 100070, China
| | - Ying-Ying Zhang
- Institute of Basic Research in Clinical Medicine, China Academy of Chinese Medical Sciences, Beijing, 100700, China
| | - Ya-Nan Yu
- Institute of Basic Research in Clinical Medicine, China Academy of Chinese Medical Sciences, Beijing, 100700, China
| | - Hong-Li Wu
- Institute of Basic Research in Clinical Medicine, China Academy of Chinese Medical Sciences, Beijing, 100700, China
| | - Zhong Wang
- Institute of Basic Research in Clinical Medicine, China Academy of Chinese Medical Sciences, Beijing, 100700, China.
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Wang Z, Nie Y, Zhang K, Xu H, Ramelot TA, Kennedy MA, Liu M, Zhu J, Yang Y. Solution structure of SHIP2 SH2 domain and its interaction with a phosphotyrosine peptide from c-MET. Arch Biochem Biophys 2018; 656:31-37. [PMID: 30165040 DOI: 10.1016/j.abb.2018.08.012] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2018] [Revised: 08/10/2018] [Accepted: 08/26/2018] [Indexed: 12/12/2022]
Abstract
SH2 domain-containing inositol 5-phosphatase 2 (SHIP2) binds with the Y1356-phosphorylated hepatocyte growth factor (HGF) receptor, c-MET, through its SH2 domain, which is essential for the role of SHIP2 in HGF-induced cell scattering and cell spreading. Previously, the experimental structure of the SH2 domain from SHIP2 (SHIP2-SH2) had not been reported, and its interaction with the Y1356-phosphorylated c-MET had not been investigated from a structural point of view. In this study, the solution structure of SHIP2-SH2 was determined by NMR spectroscopy, where it was found to adopt a typical SH2-domain fold that contains a positively-charged pocket for binding to phosphotyrosine (pY). The interaction between SHIP2-SH2 and a pY-containing peptide from c-MET (Y1356 phosphorylated) was investigated through NMR titrations. The results showed that the binding affinity of SHIP2-SH2 with the phosphopeptide is at low micromolar level, and the binding interface consists of the positively-charged pocket and its surrounding regions. Furthermore, R28, S49 and R70 were identified as key residues for the binding and may directly interact with the pY. Taken together, these findings provide structural insights into the binding of SHIP2-SH2 with the Y1356-phosphorylated c-MET, and lay a foundation for further studies of the interactions between SHIP2-SH2 and its various binding partners.
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Affiliation(s)
- Zi Wang
- State Key Laboratory of Magnetic Resonance and Atomic Molecular Physics, Wuhan Center for Magnetic Resonance, Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences, Wuhan, 430071, China; University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Yao Nie
- State Key Laboratory of Magnetic Resonance and Atomic Molecular Physics, Wuhan Center for Magnetic Resonance, Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences, Wuhan, 430071, China; University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Kunxiao Zhang
- Jiangsu Key Laboratory of Marine Pharmaceutical Compound Screening, Huaihai Institute of Technology, Lianyungang, 222005, China
| | - Henghao Xu
- Jiangsu Key Laboratory of Marine Pharmaceutical Compound Screening, Huaihai Institute of Technology, Lianyungang, 222005, China
| | - Theresa A Ramelot
- Department of Chemistry and Biochemistry, The Northeast Structural Genomics Consortium, Miami University, Oxford, OH, 45056, United States
| | - Michael A Kennedy
- Department of Chemistry and Biochemistry, The Northeast Structural Genomics Consortium, Miami University, Oxford, OH, 45056, United States
| | - Maili Liu
- State Key Laboratory of Magnetic Resonance and Atomic Molecular Physics, Wuhan Center for Magnetic Resonance, Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences, Wuhan, 430071, China
| | - Jiang Zhu
- State Key Laboratory of Magnetic Resonance and Atomic Molecular Physics, Wuhan Center for Magnetic Resonance, Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences, Wuhan, 430071, China.
| | - Yunhuang Yang
- State Key Laboratory of Magnetic Resonance and Atomic Molecular Physics, Wuhan Center for Magnetic Resonance, Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences, Wuhan, 430071, China.
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Thewke DP, Kou J, Fulmer ML, Xie Q. The HGF/MET Signaling and Therapeutics in Cancer. CURRENT HUMAN CELL RESEARCH AND APPLICATIONS 2018. [DOI: 10.1007/978-981-10-7296-3_8] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
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Thomas MP, Erneux C, Potter BVL. SHIP2: Structure, Function and Inhibition. Chembiochem 2017; 18:233-247. [DOI: 10.1002/cbic.201600541] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2016] [Indexed: 11/10/2022]
Affiliation(s)
- Mark P. Thomas
- Department of Pharmacy and Pharmacology; University of Bath; Claverton Down Bath BA2 7AY UK
| | - Christophe Erneux
- I.R.I.B.H.M.; Université Libre de Bruxelles; Campus Erasme 808 Route de Lennik 1070 Brussels Belgium
| | - Barry V. L. Potter
- Drug Discovery and Medicinal Chemistry; Department of Pharmacology; University of Oxford; Mansfield Road Oxford OX1 3QT UK
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Zhang G, Scarborough H, Kim J, Rozhok AI, Chen YA, Zhang X, Song L, Bai Y, Fang B, Liu RZ, Koomen J, Tan AC, Degregori J, Haura EB. Coupling an EML4-ALK-centric interactome with RNA interference identifies sensitizers to ALK inhibitors. Sci Signal 2016; 9:rs12. [PMID: 27811184 DOI: 10.1126/scisignal.aaf5011] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Patients with lung cancers harboring anaplastic lymphoma kinase (ALK) gene fusions benefit from treatment with ALK inhibitors, but acquired resistance inevitably arises. A better understanding of proximal ALK signaling mechanisms may identify sensitizers to ALK inhibitors that disrupt the balance between prosurvival and proapoptotic effector signals. Using affinity purification coupled with mass spectrometry in an ALK fusion lung cancer cell line (H3122), we generated an ALK signaling network and investigated signaling activity using tyrosine phosphoproteomics. We identified a network of 464 proteins composed of subnetworks with differential response to ALK inhibitors. A small hairpin RNA screen targeting 407 proteins in this network revealed 64 and 9 proteins that when knocked down sensitized cells to crizotinib and alectinib, respectively. Among these, knocking down fibroblast growth factor receptor substrate 2 (FRS2) or coiled-coil and C2 domain-containing protein 1A (CC2D1A), both scaffolding proteins, sensitized multiple ALK fusion cell lines to the ALK inhibitors crizotinib and alectinib. Collectively, our data set provides a resource that enhances our understanding of signaling and drug resistance networks consequent to ALK fusions and identifies potential targets to improve the efficacy of ALK inhibitors in patients.
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Affiliation(s)
- Guolin Zhang
- Department of Thoracic Oncology, H. Lee Moffitt Cancer Center & Research Institute, Tampa, FL 33612, USA
| | - Hannah Scarborough
- Department of Biochemistry and Molecular Genetics, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA
| | - Jihye Kim
- Department of Medicine, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA
| | - Andrii I Rozhok
- Department of Biochemistry and Molecular Genetics, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA
| | - Yian Ann Chen
- Department of Biostatistics and Bioinformatics, H. Lee Moffitt Cancer Center & Research Institute, Tampa, FL 33612, USA
| | - Xiaohui Zhang
- Department of Hematopathology and Laboratory Medicine, H. Lee Moffitt Cancer Center & Research Institute, Tampa, FL 33612, USA
| | - Lanxi Song
- Department of Thoracic Oncology, H. Lee Moffitt Cancer Center & Research Institute, Tampa, FL 33612, USA
| | - Yun Bai
- Department of Thoracic Oncology, H. Lee Moffitt Cancer Center & Research Institute, Tampa, FL 33612, USA
| | - Bin Fang
- Proteomics Core Facility, H. Lee Moffitt Cancer Center & Research Institute, Tampa, FL 33612, USA
| | - Richard Z Liu
- Department of Biostatistics and Bioinformatics, H. Lee Moffitt Cancer Center & Research Institute, Tampa, FL 33612, USA
| | - John Koomen
- Department of Molecular Oncology Program, H. Lee Moffitt Cancer Center & Research Institute, Tampa, FL 33612, USA
| | - Aik Choon Tan
- Department of Medicine, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA
| | - James Degregori
- Department of Biochemistry and Molecular Genetics, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA
| | - Eric B Haura
- Department of Thoracic Oncology, H. Lee Moffitt Cancer Center & Research Institute, Tampa, FL 33612, USA.
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Ye Y, Ge YM, Xiao MM, Guo LM, Li Q, Hao JQ, Da J, Hu WL, Zhang XD, Xu J, Zhang LJ. Suppression of SHIP2 contributes to tumorigenesis and proliferation of gastric cancer cells via activation of Akt. J Gastroenterol 2016. [PMID: 26201869 DOI: 10.1007/s00535-015-1101-0] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
BACKGROUND The Src homology 2-containing inositol 5-phosphatase 2 (SHIP2) is implicated in diabetes, arthrosclerosis, and cancer. However, the role of SHIP2 in human gastric cancer remains unclear. METHODS The expression levels of SHIP2 in gastric cancer tissues, a panel of gastric cancer cell lines, and normal gastric epithelial cells were analyzed by immunohistochemistry (IHC), Western blot, and real-time quantitative RT-PCR (qRT-PCR). Gastric cancer cells with either overexpressed SHIP2 or co-overexpressed SHIP2 and Akt were analyzed to determine cell proliferation, colony formation, apoptosis, cell migration, and invasion assays. Normal gastric epithelial cells with knockdown SHIP2 or co-knockdown SHIP2 and Akt were subjected by anchorage-independent growth assays. The effect of SHIP2 on tumor growth in vivo was detected by xenograft tumorigenesis assays. RESULTS SHIP2 was commonly downregulated in gastric cancer compared with normal gastric mucosa, and overexpression of SHIP2 inhibited cell proliferation, induced apoptosis, suppressed cell motility and invasion in gastric cancer cells in vitro, and retarded the growth of xenograft gastric tumors in vivo, while knockdown of SHIP2 in normal gastric epithelial cells promoted anchorage-independent growth. Moreover, overexpression of SHIP2 inactivated Akt, and upregulated p21, p27, and the pro-apoptotic protein Bim. Restoring Akt activation in gastric cancer cells largely blocked the inhibition of PI3K/Akt signaling by SHIP2 and reversed the inhibitory effect of SHIP2 on tumorigenesis and proliferation. CONCLUSIONS This study demonstrates, for the first time, that SHIP2 is frequently downregulated in gastric cancer, and reduced SHIP2 expression promotes tumorigenesis and proliferation of gastric cancer via activation of the PI3K/Akt signaling.
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Affiliation(s)
- Yan Ye
- Department of Immunology, Anhui Medical University, Hefei, 230032, Anhui, China
| | - Yan Mei Ge
- Department of Immunology, Anhui Medical University, Hefei, 230032, Anhui, China
| | - Miao Miao Xiao
- Department of Immunology, Anhui Medical University, Hefei, 230032, Anhui, China
| | - Li Mei Guo
- Department of Immunology, Anhui Medical University, Hefei, 230032, Anhui, China
| | - Qun Li
- Department of Immunology, Anhui Medical University, Hefei, 230032, Anhui, China
| | - Ji Qing Hao
- Department of Oncology, The First Affiliated Hospital of Anhui Medical University, Hefei, 230022, Anhui, China
| | - Jie Da
- Department of Oncology, The First Affiliated Hospital of Anhui Medical University, Hefei, 230022, Anhui, China
| | - Wang Lai Hu
- Department of Immunology, Anhui Medical University, Hefei, 230032, Anhui, China
| | - Xu Dong Zhang
- School of Medicine and Public Health, The University of Newcastle, Newcastle, NSW, 2308, Australia
| | - Jiegou Xu
- Department of Immunology, Anhui Medical University, Hefei, 230032, Anhui, China.
| | - Lin Jie Zhang
- Department of Immunology, Anhui Medical University, Hefei, 230032, Anhui, China.
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Baldanzi G, Graziani A. Physiological Signaling and Structure of the HGF Receptor MET. Biomedicines 2014; 3:1-31. [PMID: 28536396 PMCID: PMC5344233 DOI: 10.3390/biomedicines3010001] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2014] [Accepted: 12/09/2014] [Indexed: 12/13/2022] Open
Abstract
The "hepatocyte growth factor" also known as "scatter factor", is a multifunctional cytokine with the peculiar ability of simultaneously triggering epithelial cell proliferation, movement and survival. The combination of those proprieties results in the induction of an epithelial to mesenchymal transition in target cells, fundamental for embryogenesis but also exploited by tumor cells during metastatization. The hepatocyte growth factor receptor, MET, is a proto-oncogene and a prototypical transmembrane tyrosine kinase receptor. Inhere we discuss the MET molecular structure and the hepatocyte growth factor driven physiological signaling which coordinates epithelial proliferation, motility and morphogenesis.
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Affiliation(s)
- Gianluca Baldanzi
- Department Translational Medicine, University Piemonte Orientale, via Solaroli 17, 28100 Novara, Italy.
| | - Andrea Graziani
- Department Translational Medicine, University Piemonte Orientale, via Solaroli 17, 28100 Novara, Italy.
- Università Vita-Salute San Raffaele, via Olgettina 58, 20132 Milano, Italy.
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High SHIP2 expression indicates poor survival in colorectal cancer. DISEASE MARKERS 2014; 2014:218968. [PMID: 25525286 PMCID: PMC4265379 DOI: 10.1155/2014/218968] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/03/2014] [Revised: 10/23/2014] [Accepted: 11/01/2014] [Indexed: 12/21/2022]
Abstract
SH2-containing inositol 5′-phosphatase 2 (SHIP2), which generally regulates insulin signaling, cytoskeleton remodeling, and receptor endocytosis, has been suggested to play a significant role in tumor development and progression. However, the associations between SHIP2 expression and the clinical features to evaluate its clinicopathologic significance in colorectal cancer (CRC) have not been determined yet. In the present study, one-step quantitative real-time polymerase chain reaction (qPCR) test and immunohistochemistry (IHC) analysis with CRC tissue microarrays (TMA) were employed to evaluate the mRNA and protein expression of SHIP2 in CRC. The results showed that SHIP2 expression in the mRNA and protein levels was significantly higher in CRC tissues than that in corresponding noncancerous tissues (both P < 0.05). The expression of SHIP2 protein in CRC was related to lymph node metastasis (P = 0.036), distant metastasis (P = 0.001), and overall survival (P = 0.009). Kaplan-Meier method and Cox multifactor analysis suggested that high SHIP2 protein level (P = 0.040) and positive distant metastasis (P = 0.048) were critically associated with the unfavorable survival of CRC patients. The findings suggested that SHIP2 may be identified as a useful prognostic marker in CRC and targeting CRC may provide novel strategy for CRC treatment.
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Evidence for SH2 domain-containing 5'-inositol phosphatase-2 (SHIP2) contributing to a lymphatic dysfunction. PLoS One 2014; 9:e112548. [PMID: 25383712 PMCID: PMC4226566 DOI: 10.1371/journal.pone.0112548] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2014] [Accepted: 10/07/2014] [Indexed: 12/31/2022] Open
Abstract
The lymphatic vasculature plays a critical role in a number of disease conditions of increasing prevalence, such as autoimmune disorders, obesity, blood vascular diseases, and cancer metastases. Yet, unlike the blood vasculature, the tools available to interrogate the molecular basis of lymphatic dysfunction/disease have been lacking. More recently, investigators have reported that dysregulation of the PI3K pathway is involved in syndromic human diseases that involve abnormal lymphatic vasculatures, but there have been few compelling results that show the direct association of this molecular pathway with lymphatic dysfunction in humans. Using near-infrared fluorescence lymphatic imaging (NIRFLI) to phenotype and next generation sequencing (NGS) for unbiased genetic discovery in a family with non-syndromic lymphatic disease, we discovered a rare, novel mutation in INPPL1 that encodes the protein SHIP2, which is a negative regulator of the PI3K pathway, to be associated with lymphatic dysfunction in the family. In vitro interrogation shows that SHIP2 is directly associated with impairment of normal lymphatic endothelial cell (LEC) behavior and that SHIP2 associates with receptors that are associated in lymphedema, implicating its direct involvement in the lymphatic vasculature.
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15
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Lee JK, Joo KM, Lee J, Yoon Y, Nam DH. Targeting the epithelial to mesenchymal transition in glioblastoma: the emerging role of MET signaling. Onco Targets Ther 2014; 7:1933-44. [PMID: 25364264 PMCID: PMC4211615 DOI: 10.2147/ott.s36582] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023] Open
Abstract
Glioblastoma multiforme (GBM) is the most common human primary brain malignancy and has a dismal prognosis. Aggressive treatments using maximal surgical resection, radiotherapy, and temozolomide result in median survival of only 14.6 months in patients with GBM. Numerous clinical approaches using small molecule inhibitors have shown disappointing results because of the genetic heterogeneity of GBM. The epithelial to mesenchymal transition (EMT) is a crucial biological process occurring in the early development stages of many species. However, cancer cells often obtain the ability to invade and metastasize through the EMT, which triggers the scattering of cells. The hepatocyte growth factor (HGF)/MET signaling pathway is indicative of the EMT during both embryogenesis and the invasive growth of tumors, because HGF potently induces mesenchymal transition in epithelial-driven cells. Activation of MET signaling or co-overexpression of HGF and MET frequently represents aggressive growth and poor prognosis of various cancers, including GBM. Thus, efforts to treat cancers by inhibiting MET signaling using neutralizing antibodies or small molecule inhibitors have progressed during the last decade. In this review, we discuss HGF/MET signaling in the development of diseases, including cancers, as well as updates on MET inhibition therapy.
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Affiliation(s)
- Jin-Ku Lee
- Samsung Biomedical Research Institute, Sungkyunkwan University School of Medicine, Seoul, Korea ; Department of Neurosurgery, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea
| | - Kyeung Min Joo
- Department of Anatomy and Cell Biology, Sungkyunkwan University School of Medicine, Seoul, Korea
| | - Jeongwu Lee
- Department of Stem Cell Biology and Regenerative Medicine, Lerner Research Institute, Cleveland Clinic, Cleveland, OH, USA
| | - Yeup Yoon
- Samsung Advanced Institute for Health Sciences and Technology, Sungkyunkwan University School of Medicine, Seoul, Korea
| | - Do-Hyun Nam
- Department of Neurosurgery, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea ; Samsung Advanced Institute for Health Sciences and Technology, Sungkyunkwan University School of Medicine, Seoul, Korea
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16
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Fu CH, Lin RJ, Yu J, Chang WW, Liao GS, Chang WY, Tseng LM, Tsai YF, Yu JC, Yu AL. A Novel Oncogenic Role of Inositol Phosphatase SHIP2 in ER-Negative Breast Cancer Stem Cells: Involvement of JNK/Vimentin Activation. Stem Cells 2014; 32:2048-60. [DOI: 10.1002/stem.1735] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2013] [Revised: 03/19/2014] [Accepted: 04/09/2014] [Indexed: 12/26/2022]
Affiliation(s)
- Chiung-Hui Fu
- Graduate Institute of Life Sciences, National Defense Medical Center; Taipei Taiwan
- Genomics Research Center, Academia Sinica; Taipei Taiwan
- Institute of Stem Cell and Translational Cancer Research, Chang Gung Memorial Hospital at Linkou; Taoyuan Taiwan
| | - Ruey-Jen Lin
- Genomics Research Center, Academia Sinica; Taipei Taiwan
- Institute of Stem Cell and Translational Cancer Research, Chang Gung Memorial Hospital at Linkou; Taoyuan Taiwan
| | - John Yu
- Institute of Stem Cell and Translational Cancer Research, Chang Gung Memorial Hospital at Linkou; Taoyuan Taiwan
- Institute of Cellular and Organismic Biology, Academia Sinica; Taipei Taiwan
| | - Wen-Wei Chang
- Genomics Research Center, Academia Sinica; Taipei Taiwan
- School of Biomedical Sciences; Chung Shan Medical University; Taichung Taiwan
- Department of Medical Research; Chung Shan Medical University Hospital; Taichung Taiwan
| | - Guo-Shiou Liao
- Division of General Surgery, Department of Surgery; Tri-Service General Hospital; Taipei Taiwan
| | - Wen-Ying Chang
- Genomics Research Center, Academia Sinica; Taipei Taiwan
- Institute of Stem Cell and Translational Cancer Research, Chang Gung Memorial Hospital at Linkou; Taoyuan Taiwan
| | - Ling-Ming Tseng
- Division of General Surgery, Department of Surgery; Taipei-Veterans General Hospital; Taipei Taiwan
- National Yang Ming University; Taipei Taiwan
| | - Yi-Fang Tsai
- Division of General Surgery, Department of Surgery; Taipei-Veterans General Hospital; Taipei Taiwan
| | - Jyh-Cherng Yu
- Graduate Institute of Life Sciences, National Defense Medical Center; Taipei Taiwan
- Division of General Surgery, Department of Surgery; Tri-Service General Hospital; Taipei Taiwan
| | - Alice L. Yu
- Graduate Institute of Life Sciences, National Defense Medical Center; Taipei Taiwan
- Genomics Research Center, Academia Sinica; Taipei Taiwan
- Institute of Stem Cell and Translational Cancer Research, Chang Gung Memorial Hospital at Linkou; Taoyuan Taiwan
- Department of Pediatrics; University of California in San Diego; San Diego California USA
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17
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Li B, Krakow D, Nickerson DA, Bamshad MJ, Chang Y, Lachman RS, Yilmaz A, Kayserili H, Cohn DH. Opsismodysplasia resulting from an insertion mutation in the SH2 domain, which destabilizes INPPL1. Am J Med Genet A 2014; 164A:2407-11. [PMID: 24953221 DOI: 10.1002/ajmg.a.36640] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2014] [Accepted: 05/08/2014] [Indexed: 12/15/2022]
Affiliation(s)
- Bing Li
- Department of Molecular, Cell and Developmental Biology, University of California Los Angeles, Los Angeles, California
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18
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Trésaugues L, Silvander C, Flodin S, Welin M, Nyman T, Gräslund S, Hammarström M, Berglund H, Nordlund P. Structural basis for phosphoinositide substrate recognition, catalysis, and membrane interactions in human inositol polyphosphate 5-phosphatases. Structure 2014; 22:744-55. [PMID: 24704254 DOI: 10.1016/j.str.2014.01.013] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2013] [Revised: 01/24/2014] [Accepted: 01/24/2014] [Indexed: 11/15/2022]
Abstract
SHIP2, OCRL, and INPP5B belong to inositol polyphosphate 5-phophatase subfamilies involved in insulin regulation and Lowes syndrome. The structural basis for membrane recognition, substrate specificity, and regulation of inositol polyphosphate 5-phophatases is still poorly understood. We determined the crystal structures of human SHIP2, OCRL, and INPP5B, the latter in complex with phosphoinositide substrate analogs, which revealed a membrane interaction patch likely to assist in sequestering substrates from the lipid bilayer. Residues recognizing the 1-phosphate of the substrates are highly conserved among human family members, suggesting similar substrate binding modes. However, 3- and 4-phosphate recognition varies and determines individual substrate specificity profiles. The high conservation of the environment of the scissile 5-phosphate suggests a common reaction geometry for all members of the human 5-phosphatase family.
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Affiliation(s)
- Lionel Trésaugues
- Structural Genomics Consortium, Karolinska Institutet, 17177 Stockholm, Sweden
| | - Camilla Silvander
- Structural Genomics Consortium, Karolinska Institutet, 17177 Stockholm, Sweden.
| | - Susanne Flodin
- Structural Genomics Consortium, Karolinska Institutet, 17177 Stockholm, Sweden
| | - Martin Welin
- Structural Genomics Consortium, Karolinska Institutet, 17177 Stockholm, Sweden
| | - Tomas Nyman
- Structural Genomics Consortium, Karolinska Institutet, 17177 Stockholm, Sweden
| | - Susanne Gräslund
- Structural Genomics Consortium, Karolinska Institutet, 17177 Stockholm, Sweden
| | - Martin Hammarström
- Structural Genomics Consortium, Karolinska Institutet, 17177 Stockholm, Sweden
| | - Helena Berglund
- Structural Genomics Consortium, Karolinska Institutet, 17177 Stockholm, Sweden
| | - Pär Nordlund
- Structural Genomics Consortium, Karolinska Institutet, 17177 Stockholm, Sweden; Division of Biophysics, Department of Medical Biochemistry and Biophysics, Karolinska Institutet, 17177 Stockholm, Sweden; Centre for Biomedical Structural Biology, School of Biological Sciences, Nanyang Technological University, 637551, Singapore.
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Krawczyk J, Keane N, Swords R, O'Dwyer M, Freeman CL, Giles FJ. Perifosine--a new option in treatment of acute myeloid leukemia? Expert Opin Investig Drugs 2013; 22:1315-27. [PMID: 23931614 DOI: 10.1517/13543784.2013.826648] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
INTRODUCTION Perifosine is a novel targeted oral Akt inhibitor. In preclinical leukemia models, perifosine has an independent cytotoxic potential but also synergizes well with other rationally selected targeted agents. The evidence from clinical trials supporting the use of perifosine in the therapy of leukemias is limited. The optimal dose and schedule have yet to be defined. However, given its favorable toxicity profile and mechanism of action, the therapeutic potential of perifosine should be evaluated in well-designed clinical trials. AREAS COVERED The role of the phosphatidylinositol-3 kinase (PI3K)/Akt zpathway in normal cells, cancer and leukemias is discussed. The mechanism of action of perifosine and the basic information on the development and chemical properties are summarized. The evidence from in vivo and in vitro studies is presented. The efficacy and side effect profile are summarized. EXPERT OPINION The safety and tolerability profile of perifosine are satisfactory. The evidence from clinical trials in patients with leukemias is very limited. The preclinical data are encouraging. Perifosine has the potential to play a role in the treatment of leukemias in the future. Its role needs to be confirmed in clinical trials.
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20
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Xie J, Erneux C, Pirson I. How does SHIP1/2 balance PtdIns(3,4)P2 and does it signal independently of its phosphatase activity? Bioessays 2013; 35:733-43. [PMID: 23650141 DOI: 10.1002/bies.201200168] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
The number of cellular events identified as being directly or indirectly modulated by phosphoinositides dramatically increased in the recent years. Part of the complexity results from the fact that the seven phosphoinositides play second messenger functions in many different areas of growth factors and insulin signaling, cytoskeletal organization, membrane dynamics, trafficking, or nuclear signaling. PtdIns(3,4)P2 is commonly reported as a product of the SH2 domain-containing inositol 5-phosphatases 1/2 (SHIP1 and SHIP2) that dephosphorylate PtdIns(3,4,5)P3 at the 5-position. Here we discuss recent interest in PtdIns(3,4)P2 signaling highlighting its involvement in key cellular mechanisms such as cell adhesion, migration, and cytoskeletal regulation. We question and discuss the involvement of SHIP2 either as a PI 5-phosphatase or as a scaffold protein in insulin signaling, cytoskeletal dynamics, and endocytosis of growth factor receptors.
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Affiliation(s)
- Jingwei Xie
- Department of Pathophysiology, China Medical University, Heping District, Shenyang Liaoning Province, China
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21
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Abstract
Phosphoinositide signalling molecules interact with a plethora of effector proteins to regulate cell proliferation and survival, vesicular trafficking, metabolism, actin dynamics and many other cellular functions. The generation of specific phosphoinositide species is achieved by the activity of phosphoinositide kinases and phosphatases, which phosphorylate and dephosphorylate, respectively, the inositol headgroup of phosphoinositide molecules. The phosphoinositide phosphatases can be classified as 3-, 4- and 5-phosphatases based on their specificity for dephosphorylating phosphates from specific positions on the inositol head group. The SAC phosphatases show less specificity for the position of the phosphate on the inositol ring. The phosphoinositide phosphatases regulate PI3K/Akt signalling, insulin signalling, endocytosis, vesicle trafficking, cell migration, proliferation and apoptosis. Mouse knockout models of several of the phosphoinositide phosphatases have revealed significant physiological roles for these enzymes, including the regulation of embryonic development, fertility, neurological function, the immune system and insulin sensitivity. Importantly, several phosphoinositide phosphatases have been directly associated with a range of human diseases. Genetic mutations in the 5-phosphatase INPP5E are causative of the ciliopathy syndromes Joubert and MORM, and mutations in the 5-phosphatase OCRL result in Lowe's syndrome and Dent 2 disease. Additionally, polymorphisms in the 5-phosphatase SHIP2 confer diabetes susceptibility in specific populations, whereas reduced protein expression of SHIP1 is reported in several human leukaemias. The 4-phosphatase, INPP4B, has recently been identified as a tumour suppressor in human breast and prostate cancer. Mutations in one SAC phosphatase, SAC3/FIG4, results in the degenerative neuropathy, Charcot-Marie-Tooth disease. Indeed, an understanding of the precise functions of phosphoinositide phosphatases is not only important in the context of normal human physiology, but to reveal the mechanisms by which these enzyme families are implicated in an increasing repertoire of human diseases.
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22
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Shimizu K, Taniyama Y, Sanada F, Iwabayashi M, Azuma J, Iekushi K, Katsuragi N, Otsu R, Shibata K, Ishikawa Y, Rakugi H, Morishita R. Novel mechanism of hepatocyte growth factor against prevention of inflammation and oxidative stress. Inflamm Regen 2013. [DOI: 10.2492/inflammregen.33.136] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
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23
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Shimizu K, Taniyama Y, Sanada F, Azuma J, Iwabayashi M, Iekushi K, Rakugi H, Morishita R. Hepatocyte Growth Factor Inhibits Lipopolysaccharide-Induced Oxidative Stress via Epithelial Growth Factor Receptor Degradation. Arterioscler Thromb Vasc Biol 2012; 32:2687-93. [DOI: 10.1161/atvbaha.112.300041] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Objective—
Lipopolysaccharide (LPS) triggers sepsis and systemic inflammatory response syndrome, which results in multiple organ failure. Our recent reports demonstrated that hepatocyte growth factor (HGF) attenuated angiotensin II–induced oxidative stress via epithelial growth factor receptor (EGFR) degradation in vascular smooth muscle cells. Here, we examined whether HGF can protect against systemic inflammatory response syndrome induced by LPS and investigated the mechanism.
Methods and Results—
HGF inhibited the increase in the expression of vascular cell adhesion molecule-1 and EGFR by LPS in vitro. HGF inhibited colocalization of EGFR and Src homology domain 2–containing inositol 5′-phosphatase 2. Furthermore, HGF inhibited reactive oxygen species production. We also injected LPS into HGF transgenic mice with increased HGF serum concentration and their littermates. HGF transgenic mice reduced LPS-induced vascular cell adhesion molecule-1 and reactive oxygen species compared with control, accompanied by significant EGFR degradation. Furthermore, HGF transgenic mice significantly improved survival in the LPS injection model.
Conclusion—
The present study revealed inhibition of LPS-induced vascular cell adhesion molecule-1 expression by HGF via the degradation of EGFR. We demonstrated that HGF regulated Src homology domain 2–containing inositol 5′-phosphatase 2 recruitment to EGFR and inhibited LPS-induced inflammation via EGFR degradation. This effect of HGF may be useful for the treatment of inflammatory disease.
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Affiliation(s)
- Kazutaka Shimizu
- From the Departments of Clinical Gene Therapy (K.S., Y.T., F.S., J.A., M.I., K.I., R.M.) and Geriatric Medicine and Nephrology (Y.T., J.A., K.I., H.R.), Osaka University Graduate School of Medicine, Yamadaoka, Suita, Japan
| | - Yoshiaki Taniyama
- From the Departments of Clinical Gene Therapy (K.S., Y.T., F.S., J.A., M.I., K.I., R.M.) and Geriatric Medicine and Nephrology (Y.T., J.A., K.I., H.R.), Osaka University Graduate School of Medicine, Yamadaoka, Suita, Japan
| | - Fumihiro Sanada
- From the Departments of Clinical Gene Therapy (K.S., Y.T., F.S., J.A., M.I., K.I., R.M.) and Geriatric Medicine and Nephrology (Y.T., J.A., K.I., H.R.), Osaka University Graduate School of Medicine, Yamadaoka, Suita, Japan
| | - Junya Azuma
- From the Departments of Clinical Gene Therapy (K.S., Y.T., F.S., J.A., M.I., K.I., R.M.) and Geriatric Medicine and Nephrology (Y.T., J.A., K.I., H.R.), Osaka University Graduate School of Medicine, Yamadaoka, Suita, Japan
| | - Masaaki Iwabayashi
- From the Departments of Clinical Gene Therapy (K.S., Y.T., F.S., J.A., M.I., K.I., R.M.) and Geriatric Medicine and Nephrology (Y.T., J.A., K.I., H.R.), Osaka University Graduate School of Medicine, Yamadaoka, Suita, Japan
| | - Kazuma Iekushi
- From the Departments of Clinical Gene Therapy (K.S., Y.T., F.S., J.A., M.I., K.I., R.M.) and Geriatric Medicine and Nephrology (Y.T., J.A., K.I., H.R.), Osaka University Graduate School of Medicine, Yamadaoka, Suita, Japan
| | - Hiromi Rakugi
- From the Departments of Clinical Gene Therapy (K.S., Y.T., F.S., J.A., M.I., K.I., R.M.) and Geriatric Medicine and Nephrology (Y.T., J.A., K.I., H.R.), Osaka University Graduate School of Medicine, Yamadaoka, Suita, Japan
| | - Ryuichi Morishita
- From the Departments of Clinical Gene Therapy (K.S., Y.T., F.S., J.A., M.I., K.I., R.M.) and Geriatric Medicine and Nephrology (Y.T., J.A., K.I., H.R.), Osaka University Graduate School of Medicine, Yamadaoka, Suita, Japan
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24
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Lam PY, Yoo SK, Green JM, Huttenlocher A. The SH2-domain-containing inositol 5-phosphatase (SHIP) limits the motility of neutrophils and their recruitment to wounds in zebrafish. J Cell Sci 2012; 125:4973-8. [PMID: 22946052 DOI: 10.1242/jcs.106625] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
Neutrophil recruitment to sites of injury or infection is essential for host defense, but it needs to be tightly regulated to prevent tissue damage. Phosphoinositide 3-kinase (PI3K), which generates the phosphatidylinositol (3,4,5)-trisphosphate [PI(3,4,5)P(3)], is necessary for neutrophil motility in vivo; however, the role of SH2-domain-containing 5-inositol phosphatase (SHIP) enzymes, which hydrolyze PI(3,4,5)P(3) to phosphatidylinositol 3,4-bisphosphate [PI(3,4)P(2)], is not well understood. Here we show that SHIP phosphatases limit neutrophil motility in live zebrafish. Using real-time imaging of bioprobes specific for PI(3,4,5)P(3) and PI(3,4)P(2) in neutrophils, we found that PI(3,4,5)P(3) and PI(3,4)P(2) accumulate at the leading edge while PI(3,4)P(2) also localizes to the trailing edge of migrating neutrophils in vivo. Depletion of SHIP phosphatases using morpholino oligonucleotides led to increased neutrophil 3D motility and neutrophil infiltration into wounds. The increase in neutrophil wound recruitment in SHIP morphants was rescued by treatment with low dose PI3Kγ inhibitor, suggesting that SHIP limits neutrophil motility by modulating PI3K signaling. Moreover, overexpression of the SHIP phosphatase domain in neutrophils impaired neutrophil 3D migration. Taken together, our findings suggest that SHIP phosphatases control neutrophil inflammation by limiting neutrophil motility in vivo.
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Affiliation(s)
- Pui-ying Lam
- Department of Medical Microbiology and Immunology; University of Wisconsin-Madison, Madison, WI 53706, USA
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25
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Abstract
c-MET is a receptor tyrosine kinase that, after binding with its ligand, hepatocyte growth factor, activates a wide range of different cellular signaling pathways, including those involved in proliferation, motility, migration and invasion. Although c-MET is important in the control of tissue homeostasis under normal physiological conditions, it has also been found to be aberrantly activated in human cancers via mutation, amplification or protein overexpression. This paper provides an overview of the c-MET signaling pathway, including its role in the development of cancers, and provides a rationale for targeting the pathway as a possible treatment option.
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26
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Edimo WE, Janssens V, Waelkens E, Erneux C. Reversible Ser/Thr SHIP phosphorylation: a new paradigm in phosphoinositide signalling?: Targeting of SHIP1/2 phosphatases may be controlled by phosphorylation on Ser and Thr residues. Bioessays 2012; 34:634-42. [PMID: 22641604 DOI: 10.1002/bies.201100195] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
Phosphoinositide (PI) phosphatases such as the SH2 domain-containing inositol 5-phosphatases 1/2 (SHIP1 and 2) are important signalling enzymes in human physiopathology. SHIP1/2 interact with a large number of immune and growth factor receptors. Tyrosine phosphorylation of SHIP1/2 has been considered to be the determining regulatory modification. However, here we present a hypothesis, based on recent key publications, highlighting the determining role of Ser/Thr phosphorylation in regulating several key properties of SHIP1/2. Since a subunit of the Ser/Thr phosphatase PP2A has been shown to interact with SHIP2, a putative mechanism for reversing SHIP2 Ser/Thr phosphorylation can be anticipated. PI phosphatases are potential target molecules in human diseases, particularly, but not exclusively, in cancer and diabetes. Therefore, this novel regulatory mechanism deserves further attention in the hunt for discovering novel or complementary therapeutic strategies. This mechanism may be more broadly involved in regulating PI signalling in the case of synaptojanin1 or the phosphatase, tensin homolog, deleted on chromosome TEN.
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Affiliation(s)
- William's Elong Edimo
- Institut de Recherche Interdisciplinaire (IRIBHM), Université Libre de Bruxelles, Campus Erasme, Brussels, Belgium
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27
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Erneux C, Edimo WE, Deneubourg L, Pirson I. SHIP2 multiple functions: a balance between a negative control of PtdIns(3,4,5)P₃ level, a positive control of PtdIns(3,4)P₂ production, and intrinsic docking properties. J Cell Biochem 2011; 112:2203-9. [PMID: 21503961 DOI: 10.1002/jcb.23146] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
The SH2 domain containing inositol 5-phosphatase 2 (SHIP2) belongs to the family of the mammalian inositol polyphosphate 5-phosphatases. The two closely related isoenzymes SHIP1 (or SHIP) and SHIP2 contain a N-terminal SH2 domain, a catalytic domain, potential PTB domain-binding sites (NPXY), and C-terminal proline-rich regions with consensus sites for SH3 domain interactions. In addition, SHIP2 contains a unique sterile alpha motif (SAM) domain that could be involved in SAM-SAM domain interactions with other proteins or receptors. SHIP2 also shows the presence of an ubiquitin interacting motif at the C-terminal end. SHIP2 is essentially a PI(3,4,5)P(3) 5-phosphatase that negatively controls PI(3,4,5)P(3) levels in intact cells and produce PI(3,4)P(2) . Depending on the cells and stimuli, PI(3,4)P(2) could accumulate at important levels and be a "second messenger" by its own. It could interact with a very large number of target proteins such as PKB or TAPP1 and 2 that control insulin sensitivity. In addition to its catalytic activity, SHIP2 is also a docking protein for a large number of proteins: Cytoskeletal, focal adhesion proteins, scaffold proteins, adaptors, protein phosphatases, and tyrosine kinase associated receptors. These interactions could play a role in the control of cell adhesion, migration, or endocytosis of some receptors. SHIP2 could be acting independently of its phosphatase activity being part of a protein network of some receptors, e.g., the EGF receptor or BCR/ABL. These non-catalytic properties associated to a PI phosphatase have also been reported for other enzymes of the metabolism of myo-inositol such as Ins(1,4,5)P(3) 3-kinases, inositol phosphate multikinase (IPMK), or PTEN.
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Affiliation(s)
- Christophe Erneux
- Institut de Recherche Interdisciplinaire (IRIBHM), Université Libre de Bruxelles, Campus Erasme, Bldg. C, 808 Route de Lennik, 1070 Brussels, Belgium.
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28
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Mehta P, Wavreille AS, Justiniano SE, Marsh RL, Yu J, Burry RW, Jarjoura D, Eubank T, Caligiuri MA, Butchar JP, Tridandapani S. LyGDI, a novel SHIP-interacting protein, is a negative regulator of FcγR-mediated phagocytosis. PLoS One 2011; 6:e21175. [PMID: 21695085 PMCID: PMC3114867 DOI: 10.1371/journal.pone.0021175] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2010] [Accepted: 05/23/2011] [Indexed: 12/28/2022] Open
Abstract
SHIP and SHIP-2 are inositol phosphatases that regulate FcγR-mediated phagocytosis through catalytic as well as non-catalytic mechanisms. In this study we have used two-dimensional fluorescence difference gel electrophoresis (DIGE) analysis to identify downstream signaling proteins that uniquely associate with SHIP or SHIP-2 upon FcγR clustering in human monocytes. We identified LyGDI as a binding partner of SHIP, associating inducibly with the SHIP/Grb2/Shc complex. Immunodepletion and competition experiments with recombinant SHIP domains revealed that Grb2 and the proline-rich domain of SHIP were necessary for SHIP-LyGDI association. Functional studies in primary human monocytes showed that LyGDI sequesters Rac in the cytosol, preventing it from localizing to the membrane. Consistent with this, suppression of LyGDI expression resulted in significantly enhanced FcγR-mediated phagocytosis.
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Affiliation(s)
- Payal Mehta
- The Ohio State Biochemistry Program, The Ohio State University, Columbus, Ohio, United States of America
| | - Anne-Sophie Wavreille
- Department of Internal Medicine, The Ohio State University, Columbus, Ohio, United States of America
| | - Steven E. Justiniano
- Department of Internal Medicine, The Ohio State University, Columbus, Ohio, United States of America
| | - Rachel L. Marsh
- Department of Internal Medicine, The Ohio State University, Columbus, Ohio, United States of America
| | - Jianhua Yu
- Department of Molecular Virology, Immunology and Medical Genetics, The Ohio State University, Columbus, Ohio, United States of America
| | - Richard W. Burry
- Campus Microscopy and Imaging Facility, The Ohio State University, Columbus, Ohio, United States of America
| | - David Jarjoura
- Center for Biostatistics, The Ohio State University, Columbus, Ohio, United States of America
| | - Timothy Eubank
- Department of Internal Medicine, The Ohio State University, Columbus, Ohio, United States of America
- Comprehensive Cancer Center, The Ohio State University, Columbus, Ohio, United States of America
| | - Michael A. Caligiuri
- Department of Internal Medicine, The Ohio State University, Columbus, Ohio, United States of America
- Comprehensive Cancer Center, The Ohio State University, Columbus, Ohio, United States of America
| | - Jonathan P. Butchar
- Department of Internal Medicine, The Ohio State University, Columbus, Ohio, United States of America
- Comprehensive Cancer Center, The Ohio State University, Columbus, Ohio, United States of America
| | - Susheela Tridandapani
- The Ohio State Biochemistry Program, The Ohio State University, Columbus, Ohio, United States of America
- Department of Internal Medicine, The Ohio State University, Columbus, Ohio, United States of America
- Comprehensive Cancer Center, The Ohio State University, Columbus, Ohio, United States of America
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Abstract
IMPORTANCE OF THE FIELD Inositol polyphosphate 5-phosphatase (SHIP2) is an important negative regulator of intracellular phosphatidylinositol phosphate, a key second messenger of various intracellular signaling pathways. The functional upregulation of SHIP2 results in signaling blockade, leading to related disorders. AREAS COVERED IN THIS REVIEW We first summarize the role of SHIP2 in the regulation of insulin signaling and type 2 diabetes, including remarkable advances in pharmacological approaches. In addition, this review highlights new findings regarding the involvement of SHIP2 in a number of diseases, including cancer, neurodegenerative diseases, and atherosclerosis. WHAT THE READER WILL GAIN Recently identified small-molecule inhibitors of SHIP2 phosphatase activity emphasize the potential therapeutic value of SHIP2. In addition, currently available evidence demonstrates the importance of the scaffolding-type protein function of SHIP2. Understanding this interesting function will help clarify the complicated involvement of SHIP2 in various disorders. TAKE HOME MESSAGE Recent studies have demonstrated that SHIP2 is a promising therapeutic target for not only type 2 diabetes, but also cancer, neurodegenerative diseases, and atherosclerosis. Targeting SHIP2 through specific small-molecule inhibitors will have beneficial effects on these diseases.
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Affiliation(s)
- Akira Suwa
- Astellas Pharma, Inc., Pharmacology Research Labs, Drug Discovery Research, 21, Miyukigaoka, Tsukuba-shi, Ibaraki 305-8585, Japan.
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Jurynec MJ, Grunwald DJ. SHIP2, a factor associated with diet-induced obesity and insulin sensitivity, attenuates FGF signaling in vivo. Dis Model Mech 2010; 3:733-42. [PMID: 20616095 DOI: 10.1242/dmm.000703] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
SH2-domain-containing inositol phosphatase 2 (SHIP2) belongs to a small family of phosphoinositide 5-phosphatases that help terminate intracellular signaling initiated by activated receptor tyrosine kinases. Mammalian SHIP2 is viewed primarily as an attenuator of insulin signaling and has become a prominent candidate target for therapeutic agents that are designed to augment insulin signaling. Despite this view, no signaling pathway has yet been demonstrated as being affected directly by SHIP2 function in vivo, and in vitro studies indicate that the protein may function in multiple signaling pathways. Here, we analyze the role of a SHIP2 family member in the early zebrafish embryo where developmental and gene expression defects can be used to assay specific signaling pathways. The zebrafish ship2a transcript is maternally supplied, and inhibiting the expression of its protein product results in the expansion of dorsal tissue fates at the expense of ventral ones. We show that the developmental defects are the result of perturbation of fibroblast growth factor (FGF) signaling in the early embryo. Loss of Ship2a leads to an increased and expanded expression of outputs of FGF-mediated signaling, including FGF-dependent gene expression and activated mitogen-activated protein kinase (MAPK) signaling. Our findings demonstrate that Ship2a attenuates the FGF signaling pathway in vivo and functions in the establishment of normal tissue patterning in the early embryo. We suggest that modulation of FGF signaling may be a principal function of SHIP2 in mammals.
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Affiliation(s)
- Michael J Jurynec
- Department of Human Genetics, University of Utah, Salt Lake City, UT 84112, USA
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31
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Zwaenepoel K, Goris J, Erneux C, Parker PJ, Janssens V. Protein phosphatase 2A PR130/B''alpha1 subunit binds to the SH2 domain-containing inositol polyphosphate 5-phosphatase 2 and prevents epidermal growth factor (EGF)-induced EGF receptor degradation sustaining EGF-mediated signaling. FASEB J 2009; 24:538-47. [PMID: 19825976 DOI: 10.1096/fj.09-140228] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
To elucidate novel cell biological functions of specific protein phosphatase 2A (PP2A) holoenzymes, we identified and biochemically characterized a complex between the Src homology 2 (SH2) domain-containing inositol polyphosphate 5-phosphatase 2 (SHIP2) and a PP2A holoenzyme comprising PR130/B''alpha1 as a regulatory subunit (PP2A(T130)) in several mammalian cell lines. PR130/B''alpha1 and SHIP2 partially colocalize in untreated HeLa cells, and both translocate to the cell membrane on epidermal growth factor (EGF) stimulation. Concomitantly, a transient EGF-dependent interaction of PR130/B''alpha1 with the EGF receptor (EGFR) was observed, whereas the SHIP2-PR130 interaction remained constitutive. As previously reported for SHIP2, RNA interference-mediated knockdown of PR130 in COS-7 cells resulted in increased EGF-induced proteasome-dependent EGFR degradation, and an increased interaction of EGFR with the E3 ligase c-Cbl. In concordance with faster EGFR clearance or desensitization, intrinsic EGFR kinase activity (phospho-Tyr-1068) and downstream protein kinase B and extracellular signal-regulated kinase/mitogen-activated protein kinase pathways were more rapidly inactivated in PR130-knockdown cells. Notably, these effects could be rescued by reintroduction of RNA interference-resistant Myc-PR130, excluding any off-target effect. These data highlight a novel biological role of the PP2A(T130) holoenzyme in EGF signaling through interaction with EGFR and the phosphatidylinositol (3,4,5)-trisphosphate 5-phosphatase SHIP2. This interaction may be of clinical relevance as dysfunction of EGF-mediated signaling has been linked to various human cancers.
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Affiliation(s)
- Karen Zwaenepoel
- Protein Phosphorylation and Proteomics Laboratory, Dept. of Molecular Cell Biology, Faculty of Medicine, Katholieke Universiteit Leuven, B-3000 Leuven, Belgium
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32
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Sanada F, Taniyama Y, Iekushi K, Azuma J, Okayama K, Kusunoki H, Koibuchi N, Doi T, Aizawa Y, Morishita R. Negative action of hepatocyte growth factor/c-Met system on angiotensin II signaling via ligand-dependent epithelial growth factor receptor degradation mechanism in vascular smooth muscle cells. Circ Res 2009; 105:667-75, 13 p following 675. [PMID: 19713535 DOI: 10.1161/circresaha.109.202713] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
RATIONALE Neointimal hyperplasia contributes to atherosclerosis and restenosis after percutaneous coronary intervention. Vascular injury in each of these conditions results in the release of mitogenic growth factors and hormones that contribute to pathological vascular smooth muscle cell growth and inflammation. Hepatocyte growth factor (HGF) is known as an antiinflammatory growth factor, although it is downregulated in injured tissue. However, the precise mechanism how HGF reduces inflammation is unclear. OBJECTIVE To elucidate the mechanism how HGF and its receptor c-Met reduces angiotensin II (Ang II)-induced inflammation. METHODS AND RESULTS HGF reduced Ang II-induced vascular smooth muscle cell growth and inflammation by controlling translocation of SHIP2 (Src homology domain 2-containing inositol 5'-phosphatase 2), which led to Ang II-dependent degradation of epithelial growth factor receptor. Moreover, the present study also revealed a preventive effect of HGF on atherosclerotic change in an Ang II infusion and cuff HGF transgenic mouse model. CONCLUSIONS These data suggest that the HGF/c-Met system might regulate extrinsic factor signaling that maintains the homeostasis of organs.
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Affiliation(s)
- Fumihiro Sanada
- Department of Clinical Gene Therapy, Osaka University Graduate School of Medicine, Yamada-oka, Suita, Japan
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33
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Stella MC, Trusolino L, Comoglio PM. The Slit/Robo system suppresses hepatocyte growth factor-dependent invasion and morphogenesis. Mol Biol Cell 2009; 20:642-57. [PMID: 19005219 PMCID: PMC2626568 DOI: 10.1091/mbc.e08-03-0321] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2008] [Revised: 08/11/2008] [Accepted: 11/04/2008] [Indexed: 12/13/2022] Open
Abstract
The Slit protein acts through the Roundabout receptor as a paracrine chemorepellent in axon guidance and as an inhibitor in leukocyte chemotaxis, but its role in epithelial cell motility and morphogenesis remains largely unexplored. We report that nontransformed epithelial cells and cancerous cells empower the Slit-2/Robo1 signaling system to limit outward migration in response to motogenic attractants and to remain positionally confined within their primitive location. Short hairpin RNA-mediated depletion of SLIT-2 or ectopic expression of a soluble decoy Robo enhance hepatocyte growth factor (HGF)-induced migration, matrix invasion, and tubulogenesis, concomitantly with the up-regulation of Cdc-42 and the down-modulation of Rac-1 activities. Accordingly, autocrine overexpression or exogenous administration of Slit-2 prevent HGF-triggered motile responses, reduce Cdc-42 activation, and stimulate Rac-1. This antimigratory activity of Slit-2 derives from the inhibition of actin-based protrusive forces and from an increased adhesive strength of cadherin-mediated intercellular contacts. These results disclose a novel function for Slit and Robo in the inhibition of growth factor-mediated epithelial cell motility and morphogenesis, invoking a critical role for both molecules as natural antagonists of neoplastic invasive growth.
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Affiliation(s)
- Maria Cristina Stella
- Division of Molecular Oncology, Institute for Cancer Research and Treatment, University of Torino School of Medicine, 10060 Candiolo, Torino, Italy
| | - Livio Trusolino
- Division of Molecular Oncology, Institute for Cancer Research and Treatment, University of Torino School of Medicine, 10060 Candiolo, Torino, Italy
| | - Paolo M. Comoglio
- Division of Molecular Oncology, Institute for Cancer Research and Treatment, University of Torino School of Medicine, 10060 Candiolo, Torino, Italy
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MicroRNA-184 antagonizes microRNA-205 to maintain SHIP2 levels in epithelia. Proc Natl Acad Sci U S A 2008; 105:19300-5. [PMID: 19033458 DOI: 10.1073/pnas.0803992105] [Citation(s) in RCA: 225] [Impact Index Per Article: 14.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Despite their potential to regulate approximately one-third of the whole genome, relatively few microRNA (miRNA) targets have been experimentally validated, particularly in stratified squamous epithelia. Here we demonstrate not only that the lipid phosphatase SHIP2 is a target of miRNA-205 (miR-205) in epithelial cells, but, more importantly, that the corneal epithelial-specific miR-184 can interfere with the ability of miR-205 to suppress SHIP2 levels. This is the first example of a miRNA negatively regulating another to maintain levels of a target protein. Interfering with miR-205 function by using a synthetic antagomir, or by the ectopic expression of miR-184, leads to a coordinated damping of the Akt signaling pathway via SHIP2 induction. This was associated with a marked increase in keratinocyte apoptosis and cell death. Aggressive squamous cell carcinoma (SCC) cells exhibited elevated levels of miR-205. This was associated with a concomitant reduction in SHIP2 levels. Partial knockdown of endogenous miR-205 in SCCs markedly decreased phosphorylated Akt and phosphorylated BAD levels and increased apoptosis. We were able to increase SHIP2 levels in SCC cells after inhibition of miR-205. Therefore, miR-205 might have diagnostic value in determining the aggressivity of SCCs. Blockage of miR-205 activity with an antagomir or via ectopic expression of miR-184 could be novel therapeutic approaches for treating aggressive SCCs.
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35
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Koch A, Scherr M, Breyer B, Mancini A, Kardinal C, Battmer K, Eder M, Tamura T. Inhibition of Abl tyrosine kinase enhances nerve growth factor-mediated signaling in Bcr-Abl transformed cells via the alteration of signaling complex and the receptor turnover. Oncogene 2008; 27:4678-89. [PMID: 18427551 DOI: 10.1038/onc.2008.107] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Receptor tyrosine kinase-mediated signaling is tightly regulated by a number of cytoplasmic signaling molecules. In this report, we show that Bcr-Abl transformed chronic myelogenous leukemia (CML) cell lines, K562 and Meg-01, express the receptor for nerve growth factor (NGF), TrkA, on the cell surface; however, the NGF-mediated signal is not particularly strong. Treatment with imatinib, a potent inhibitor of Bcr-Abl tyrosine kinase, downmodulates phosphorylation of downstream molecules. Upon stimulation with NGF, Erk and Akt are phosphorylated to a much greater degree in imatinib-treated cells than in untreated cells. Knockdown of expression of Bcr-Abl using small interfering RNA technique also enhanced NGF-mediated Akt phosphorylation, indicating that Bcr-Abl kinase modifies NGF signaling directly. Imatinib treatment also enhanced NGF signaling in rat adrenal pheochromocytoma cell line PC12 that expresses TrkA and c-Abl, suggesting that it is not only restoration of responsiveness to NGF after blocking oncoprotein activity, but also c-Abl tyrosine kinase per se may be a negative regulator of growth factor signaling. Furthermore, inhibition of Abl tyrosine kinase enhanced clearance of surface TrkA after NGF treatment and simultaneously enhanced NGF-mediated signaling, suggesting that as in neuronal cells 'signaling endosomes' are formed in hematopoietic cells. To examine the role of TrkA in CML cells, we studied cell growth or colony formation in the presence or absence of imatinib with or without NGF. We found that NGF treatment induces cell survival in imatinib-treated CML cell lines, as well as colony formation of primary CD34+ CML cells, strongly suggesting that NGF/TrkA signaling contributes to aberrant signaling in CML.
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Affiliation(s)
- A Koch
- Institut für Biochemie, OE 4310, Medizinische Hochschule Hannover, Hannover, Germany
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36
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Xie J, Onnockx S, Vandenbroere I, Degraef C, Erneux C, Pirson I. The docking properties of SHIP2 influence both JIP1 tyrosine phosphorylation and JNK activity. Cell Signal 2008; 20:1432-41. [PMID: 18486448 DOI: 10.1016/j.cellsig.2008.03.010] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2008] [Revised: 03/14/2008] [Accepted: 03/19/2008] [Indexed: 12/30/2022]
Abstract
SHIP2 (SH2-containing inositol polyphosphate 5-phosphatase 2) is an ubiquitously expressed phosphatidylinositol (3,4,5)-trisphosphate (PtdIns(3,4,5)P(3)) 5-phosphatase which contains various motifs susceptible to mediate protein-protein interaction. In cell models, evidence has been provided that SHIP2 plays a role in insulin and growth factor signaling, cytoskeletal organization, cell adhesion and migration. Herein we describe the c-Jun NH2-terminal kinase (JNK)-interacting protein 1 (JIP1) as a new protein partner of SHIP2. The interaction between SHIP2 and JIP1 was confirmed in both overexpression systems and native cells. Without modifying the association of JIP1 with the MAPKs in the scaffold complex and with no apparent change of Akt phosphorylation, SHIP2 positively modulated the MLK3/JIP1-mediated JNK1 activation. Moreover, SHIP2 positively regulated the tyrosine phosphorylation of JIP1. This up-regulation was prevented by inhibitors of the Src family and Abl kinases, PP2 and Glivec. The effects of SHIP2 on JNK activity and JIP1 tyrosine phosphorylation were independent of the SHIP2 phosphoinositide 5-phosphatase activity, as similar results were obtained when using a SHIP2 catalytic inactive mutant instead of wild-type SHIP2. Together, these data suggest that by its docking properties, SHIP2 can modulate JIP1-mediated JNK pathway signaling.
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Affiliation(s)
- Jingwei Xie
- Institute of Interdisciplinary Research (IRIBHM), School of Medicine, Free University of Brussels, Campus Erasme, Building C, Route de Lennik 808, B-1070 Brussels, Belgium
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37
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Prasad NK, Tandon M, Badve S, Snyder PW, Nakshatri H. Phosphoinositol phosphatase SHIP2 promotes cancer development and metastasis coupled with alterations in EGF receptor turnover. Carcinogenesis 2007; 29:25-34. [PMID: 17893231 DOI: 10.1093/carcin/bgm213] [Citation(s) in RCA: 56] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
Phosphoinositol phosphatases are important regulators of signaling pathways relevant to both diabetes and cancer. A 3'-phosphoinositol phosphatase, phosphatase homologous to tensin (PTEN), is both a tumor suppressor and a negative regulator of insulin action. A 5'-phosphoinositol phosphatase, SH2-containing 5'-inositol phosphatase (SHIP2), regulates insulin signaling and its genetic knockout prevents high-fat diet-induced obesity in mice. SHIP2 also regulates cytoskeleton remodeling and receptor endocytosis. This and the fact that both PTEN and SHIP2 act on the same substrate suggest a potential role for SHIP2 in cancer. Here we report that, in direct contrast to PTEN, SHIP2 protein expression is elevated in a number of breast cancer cell lines. RNA interference-mediated silencing of SHIP2 in MDA-231 cells suppresses epidermal growth factor receptor (EGFR) levels by means of enhanced receptor degradation. Furthermore, endogenous SHIP2 in MDA-231 breast cancer cells supports in vitro cell proliferation, increases cellular sensitivity to drugs targeting the EGFR and supports cancer development and metastasis in nude mice. In addition, significantly high proportions (44%; P = 0.0001) of clinical specimens of breast cancer tissues in comparison with non-cancerous breast tissues contain elevated expression of SHIP2 protein. Taken together, our results demonstrate that SHIP2 is a clinically relevant novel anticancer target that links perturbed metabolism to cancer development.
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Affiliation(s)
- Nagendra K Prasad
- Department of Basic Medical Sciences and Purdue Cancer Center, Purdue University, LYNN Hall, 625 Harrison Street, West Lafayette, IN 47907, USA
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38
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Raaijmakers JH, Deneubourg L, Rehmann H, de Koning J, Zhang Z, Krugmann S, Erneux C, Bos JL. The PI3K effector Arap3 interacts with the PI(3,4,5)P3 phosphatase SHIP2 in a SAM domain-dependent manner. Cell Signal 2007; 19:1249-57. [PMID: 17314030 DOI: 10.1016/j.cellsig.2006.12.015] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2006] [Accepted: 12/27/2006] [Indexed: 10/23/2022]
Abstract
Arap3 is a phosphoinositide (PI) 3 kinase effector that serves as a GTPase activating protein (GAP) for both Arf and Rho G-proteins. The protein has multiple pleckstrin homology (PH) domains that bind preferentially phosphatidyl-inositol-3,4,5-trisphosphate (PI(3,4,5,)P3) to induce translocation of Arap3 to the plasma membrane upon PI3K activation. Arap3 also contains a Ras association (RA) domain that interacts with the small G-protein Rap1 and a sterile alpha motif (SAM) domain of unknown function. In a yeast two-hybrid screen for new interaction partners of Arap3, we identified the PI 5'-phosphatase SHIP2 as an interaction partner of Arap3. The interaction between Arap3 and SHIP2 was observed with endogenous proteins and shown to be mediated by the SAM domain of Arap3 and SHIP2. In vitro, these two domains show specificity for a heterodimeric interaction. Since it was shown previously that Arap3 has a higher affinity for PI(3,4,5,)P3 than for PI(3,4)P2, we propose that the SAM domain of Arap3 can function to recruit a negative regulator of PI3K signaling into the effector complex.
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Affiliation(s)
- Judith H Raaijmakers
- Department of Physiological Chemistry and Centre of Biomedical Genetics, UMC Utrecht, Universiteitsweg 100, 3584 CG Utrecht, The Netherlands
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39
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Mancini A, El Bounkari O, Norrenbrock AF, Scherr M, Schaefer D, Eder M, Banham AH, Pulford K, Lyne L, Whetton AD, Tamura T. FMIP controls the adipocyte lineage commitment of C2C12 cells by downmodulation of C/EBP alpha. Oncogene 2006; 26:1020-7. [PMID: 16909111 DOI: 10.1038/sj.onc.1209853] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Fms interacting protein (FMIP) is a substrate for Fms tyrosine kinase, and a nuclear/cytoplasm shuttling protein with a leucine zipper. As the phosphorylation of FMIP is observed in insulin-stimulated preadipocytes, we examined the role of FMIP in adipocyte differentiation, using the mesenchymal multipotent stem cells, C2C12 cells, that can differentiate into adipocytes, muscle cells and osteoblasts. Ectopic expression of FMIP in C2C12 impairs the adipocyte differentiation induced by treatment with insulin, dexamethasone and 3-isobutyl-1-methylxanthine. These cells exhibit muscle phenotype with multinuclear morphology. Furthermore, knockdown of endogenous FMIP expression by small interfering RNA improves adipocytic lineage commitment of C2C12 cells, while impairing muscle differentiation. Upon stimulation with insulin, CCAAT/enhancer binding protein (C/EBP)beta, but not C/EBPalpha, is upregulated in cells expressing ectopic FMIP, whereas in FMIP knockdown cells, C/EBPalpha is constitutively expressed. Ectopic expression of C/EBPalpha counteracts the effects of FMIP, whereas C/EBPalpha knockdown partially mimics the effects of FMIP in this system. Northern blot analysis and reverse transcriptase-polymerase chain reaction study reveal that ectopic FMIP-expressing cells do not contain the polyadenylated C/EBPalpha mRNA, but contain the C/EBPalpha pre-mRNA, suggesting that FMIP plays a role in RNA processing and/or export. Indeed, a member of the THO complex that plays a role in mRNA export, THOC1, is co-precipitated with FMIP. The data we have acquired on FMIP suggest that it is a target for tyrosine kinase receptors that potentiate mRNA export.
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Affiliation(s)
- A Mancini
- Institut fuer Biochemie, Medizinische Hochschule Hannover, Hannover, Germany
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40
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Chu S, Yuan X, Li Z, Jiang P, Zhang J. C-Met antisense oligodeoxynucleotide inhibits growth of glioma cells. ACTA ACUST UNITED AC 2006; 65:533-8; discussion 538. [PMID: 16720163 DOI: 10.1016/j.surneu.2005.11.024] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2005] [Accepted: 11/02/2005] [Indexed: 12/12/2022]
Abstract
BACKGROUND C-Met, a receptor tyrosine kinase, and its ligand, hepatocyte growth factor, are critical in cellular proliferation, motility, and invasion and are known to be overexpressed in gliomas. The aim of our study was therefore to investigate the effect of transfected caroboxyfluorescein-5-succimidyl ester (FAM)-labeled c-Met antisense oligonucleotide (ASODN) on growth of glioma cells. METHODS Conjugated FAM-labeled c-Met ASODN was encapsulated by LIPOFECTAMINE PLUS Reagent and then added into the human glioma cell line U251. Cultured cells were divided into 5 groups: control group, 500 nmol/L nonsense oligonucleotide (NSODN) group, 250 nmol/L ASODN group, 500 nmol/L ASODN group, and 750 nmol/L ASODN group. The intracellular distribution of c-Met ASODN was observed with fluorescence microscopy; cell growth was detected by methyl thiazole tetrazolium assay. The apoptosis of U251 cells was also examined with a flow cytometer. Semiquantitative reverse transcriptase polymerase chain reaction and Western blot examinations were carried for expression of c-Met messenger RNA (mRNA) and protein. RESULTS The blue fluorescence was seen in the cytoplast and nuclei of cells of FAM-labeled c-Met ASODN groups with fluorescence microscopy after the cells were treated with FAM-labeled c-Met ASODN-LIPOFECTAMINE PLUS Reagent complex for 3 hours. Antisense (AS) oligonucleotide caused a statistically significant reduction of cell viability (P < .05), whereas NSODN had no such changes. The cell growth was also significantly inhibited by ASODN (P < .05). After transfection, 250, 500, and 750 nmol/L ASODN induced significant apoptotic response, about 4.67% +/- 2.86%, 8.65% +/- 3.18%, and 12.76% +/- 3.15% for 24 hours (P < .05) and 7.79% +/- 1.92%, 11.43% +/- 1.54%, and 15.78% +/- 1.86% for 48 hours (P < .01), respectively. However, 500 nmol/L NSODN did not induce any significant apoptotic response until 48 hours after transfection (P > .05). A significant loss of c-Met mRNA was presented in ASODN-treated cells, and this was not seen in treatment with NSODN. Protein level was significantly decreased 48 hours after c-Met ASODN transfected. CONCLUSIONS Antisense oligonucleotide targeting c-Met can be identified as a most potent AS compound, which can inhibit cell growth and induce cell apoptosis. This provides evidence that c-Met plays a role in tumor progression of glioma by acting as an oncogene and suggests that c-Met ASODN may provide a novel approach to therapy for human glioma.
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Affiliation(s)
- Shenghua Chu
- Department of Neurosurgery, Zhongnan Hospital of Wuhan University, Wuhan 430071, China
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41
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Sharrard RM, Maitland NJ. Regulation of protein kinase B activity by PTEN and SHIP2 in human prostate-derived cell lines. Cell Signal 2006; 19:129-38. [PMID: 16842970 DOI: 10.1016/j.cellsig.2006.05.029] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2006] [Accepted: 05/29/2006] [Indexed: 10/24/2022]
Abstract
Protein Kinase B (PKB/Akt) is a key regulator of cell proliferation, motility and survival. The activation status of PKB is regulated by phosphatidylinositol 3-kinase (PI3K) via the synthesis of phosphatidylinositol-3,4,5-trisphosphate (PI(3,4,5)P3, PIP3). PTEN antagonises PI3K by degrading PIP3 to phosphatidylinositol-4,5-bisphosphate (PI(4,5)P2). Deregulation of PKB through loss of functional PTEN has frequently been implicated in the progression of tumours, including prostate cancer, and the PTEN-negative prostate cancer cell lines LNCaP and PC3 have been widely used as models for this mechanism of constitutive PKB activation. However, other enzymes in addition to PTEN can antagonise PI3K, including SHIP2, which degrades PIP3 to phosphatidylinositol-3,4-bisphosphate (PI(3,4)P2). We investigated the role of PTEN and SHIP2 in the regulation of PKB phosphorylation in a panel of human prostate-derived epithelial cell lines. In the PTEN-positive prostate-derived cell lines PNT2, PNT1a and P4E6, PI3K inhibition by LY294002 caused rapid dephosphorylation of PKB at ser473 (T(1/2)<2 min), leading to its inactivation. In the PTEN-null line LNCaP, LY294002-induced PKB dephosphorylation was much slower (T(1/2)>20 min), but in PC3 cells (also PTEN-null) it was only slightly slower than in PTEN-positive cells (T(1/2)=3 min). PKB dephosphorylation paralleled loss of plasma membrane PIP3. PNT1a, P4E6 and PC3, but not PNT2 or LNCaP, expressed SHIP2. SiRNA-mediated knockdown of SHIP2 expression markedly slowed PKB inactivation in response to LY294002 in PC3 but not in other SHIP2-positive cells, whereas knockdown of PTEN expression in PNT2, PNT1a and P4E6 resulted in higher steady-state levels of PKB phosphorylation and slowed, but did not prevent, LY294002-induced PKB inactivation. Thus SHIP2 substitutes for PTEN in the acute regulation of PKB in PC3 cells but not other prostate cell lines, where PTEN may share this role with further PIP3-degrading mechanisms.
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Affiliation(s)
- R Michael Sharrard
- YCR Cancer Research Unit, Department of Biology, University of York, Heslington, York YO10 5DD, UK.
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42
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Lazar DF, Saltiel AR. Lipid phosphatases as drug discovery targets for type 2 diabetes. Nat Rev Drug Discov 2006; 5:333-42. [PMID: 16582877 DOI: 10.1038/nrd2007] [Citation(s) in RCA: 85] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
The soaring incidence of type 2 diabetes has created pressure for new pharmaceutical strategies to treat this devastating disease. With much of the focus on overcoming insulin resistance, investigation has focused on finding ways to restore activation of the phosphatidylinositol 3'-kinase pathway, which is diminished in many patients with type 2 diabetes. Here we review the evidence that lipid phosphatases, specifically PTEN and SHIP2, attenuate this important insulin signalling pathway. Both in vivo and in vitro studies indicate their role in regulating whole-body energy metabolism, and possibly weight gain as well. The promise and challenges presented by this new class of drug discovery targets will also be discussed.
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Affiliation(s)
- Dan F Lazar
- Eli Lilly and Co., Endocrine Division, Lilly Research Laboratories, Indianapolis, Indianapolis 46285, USA.
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43
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Paternotte N, Zhang J, Vandenbroere I, Backers K, Blero D, Kioka N, Vanderwinden JM, Pirson I, Erneux C. SHIP2 interaction with the cytoskeletal protein Vinexin. FEBS J 2005; 272:6052-66. [PMID: 16302969 DOI: 10.1111/j.1742-4658.2005.04996.x] [Citation(s) in RCA: 51] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The src homology 2 (SH2) domain-containing inositol 5-phosphatase 2 (SHIP2) catalyses the dephosphorylation of phosphatidylinositol 3,4,5-trisphosphate [PtdIns(3,4,5)P3] to phosphatidylinositol 3,4-bisphosphate [PtdIns(3,4)P2]. We report the identification of the cytoskeletal protein Vinexin as a protein interacting with SHIP2. This was achieved by yeast two-hybrid screening using the C-terminal region of SHIP2 as bait. Vinexin has previously been identified as a vinculin-binding protein that plays a key role in cell spreading and cytoskeletal organization. The interaction between SHIP2 and Vinexin was confirmed in lysates of both COS-7 cells and mouse embryonic fibroblasts (MEF). The C-terminus was involved in the interaction, as shown by the transfection of a truncated C-terminus mutant of SHIP2. In addition, we showed the colocalization between Vinexin alpha and SHIP2 at the periphery of transfected COS-7 cells. When added in vitro to SHIP2, Vinexin did not affect the PtdIns(3,4,5)P3 5-phosphatase activity of SHIP2. Enhanced cell adhesion to collagen-I-coated dishes was shown upon transfection of either SHIP2 or Vinexin to COS-7 cells. This effect was no longer observed with either a catalytic mutant or the C-terminus mutant of SHIP2. It also appears SHIP2 specific; this was not seen with SHIP1. Adhesion to the same matrix was decreased in SHIP2-/- MEF cells compared with MEF+/+ cells. Our data suggest that SHIP2 interaction with Vinexin promotes the localization of SHIP2 at the periphery of the cells leaving its catalytic site intact. The complex formation between Vinexin and SHIP2 may increase cellular adhesion. The data reinforce the concept that SHIP2 is active both as a PtdIns(3,4,5)P3 5-phosphatase and as a modulator of focal contact formation.
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Affiliation(s)
- Nathalie Paternotte
- Interdisciplinary Research Institute (IRIBHM), Université Libre de Bruxelles, Brussels, Belgium
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