1
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Malnassy G, Keating CR, Gad S, Bridgeman B, Perera A, Hou W, Cotler SJ, Ding X, Choudhry M, Sun Z, Koleske AJ, Qiu W. Inhibition of Abelson Tyrosine-Protein Kinase 2 Suppresses the Development of Alcohol-Associated Liver Disease by Decreasing PPARgamma Expression. Cell Mol Gastroenterol Hepatol 2023; 16:685-709. [PMID: 37460041 PMCID: PMC10520367 DOI: 10.1016/j.jcmgh.2023.07.006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/23/2023] [Revised: 07/11/2023] [Accepted: 07/12/2023] [Indexed: 08/07/2023]
Abstract
BACKGROUND & AIMS Alcohol-associated liver disease (ALD) represents a spectrum of alcohol use-related liver diseases. Outside of alcohol abstinence, there are currently no Food and Drug Administration-approved treatments for advanced ALD, necessitating a greater understanding of ALD pathogenesis and potential molecular targets for therapeutic intervention. The ABL-family proteins, including ABL1 and ABL2, are non-receptor tyrosine kinases that participate in a diverse set of cellular functions. We investigated the role of the ABL kinases in alcohol-associated liver disease. METHODS We used samples from patients with ALD compared with healthy controls to elucidate a clinical phenotype. We established strains of liver-specific Abl1 and Abl2 knockout mice and subjected them to the National Institute on Alcohol Abuse and Alcoholism acute-on-chronic alcohol feeding regimen. Murine samples were subjected to RNA sequencing, AST, Oil Red O staining, H&E staining, Western blotting, and quantitative polymerase chain reaction to assess phenotypic changes after alcohol feeding. In vitro modeling in HepG2 cells as well as primary hepatocytes from C57BL6/J mice was used to establish this mechanistic link of ALD pathogenesis. RESULTS We demonstrate that the ABL kinases are highly activated in ALD patient liver samples as well as in liver tissues from mice subjected to an alcohol feeding regimen. We found that the liver-specific knockout of Abl2, but not Abl1, attenuated alcohol-induced steatosis, liver injury, and inflammation. Subsequent RNA sequencing and gene set enrichment analyses of mouse liver tissues revealed that relative to wild-type alcohol-fed mice, Abl2 knockout alcohol-fed mice exhibited numerous pathway changes, including significantly decreased peroxisome proliferator activated receptor (PPAR) signaling. Further examination revealed that PPARγ, a previously identified regulator of ALD pathogenesis, was induced upon alcohol feeding in wild-type mice, but not in Abl2 knockout mice. In vitro analyses revealed that shRNA-mediated knockdown of ABL2 abolished the alcohol-induced accumulation of PPARγ as well as subsequent lipid accumulation. Conversely, forced overexpression of ABL2 resulted in increased PPARγ protein expression. Furthermore, we demonstrated that the regulation of hypoxia inducible factor 1 subunit alpha (HIF1α) by ABL2 is required for alcohol-induced PPARγ expression. Furthermore, treatment with ABL kinase inhibitors attenuated alcohol-induced PPARγ expression, lipid droplet formation, and liver injury. CONCLUSIONS On the basis of our current evidence, we propose that alcohol-induced ABL2 activation promotes ALD through increasing HIF1α and the subsequent PPARγ expression, and ABL2 inhibition may serve as a promising target for the treatment of ALD.
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Affiliation(s)
- Greg Malnassy
- Department of Surgery, Loyola University Chicago Stritch School of Medicine, Maywood, Illinois; Department of Cancer Biology, Loyola University Chicago Stritch School of Medicine, Maywood, Illinois
| | - Claudia R Keating
- Department of Surgery, Loyola University Chicago Stritch School of Medicine, Maywood, Illinois; Department of Cancer Biology, Loyola University Chicago Stritch School of Medicine, Maywood, Illinois
| | - Shaimaa Gad
- Department of Surgery, Loyola University Chicago Stritch School of Medicine, Maywood, Illinois; Department of Cancer Biology, Loyola University Chicago Stritch School of Medicine, Maywood, Illinois; Department of Pharmacology, Medical Research and Clinical Studies Institute, National Research Centre, Cairo, Egypt
| | - Bryan Bridgeman
- Department of Surgery, Loyola University Chicago Stritch School of Medicine, Maywood, Illinois; Department of Cancer Biology, Loyola University Chicago Stritch School of Medicine, Maywood, Illinois
| | - Aldeb Perera
- Department of Surgery, Loyola University Chicago Stritch School of Medicine, Maywood, Illinois; Department of Cancer Biology, Loyola University Chicago Stritch School of Medicine, Maywood, Illinois
| | - Wei Hou
- Department of Surgery, Loyola University Chicago Stritch School of Medicine, Maywood, Illinois; Department of Cancer Biology, Loyola University Chicago Stritch School of Medicine, Maywood, Illinois
| | - Scott J Cotler
- Department of Medicine, Loyola University Chicago Stritch School of Medicine, Maywood, Illinois
| | - Xianzhong Ding
- Department of Pathology, Loyola University Chicago Stritch School of Medicine, Maywood, Illinois
| | - Mashkoor Choudhry
- Department of Surgery, Loyola University Chicago Stritch School of Medicine, Maywood, Illinois
| | - Zhaoli Sun
- Department of Surgery, Johns Hopkins University School of Medicine, Baltimore, Maryland
| | - Anthony J Koleske
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, Connecticut
| | - Wei Qiu
- Department of Surgery, Loyola University Chicago Stritch School of Medicine, Maywood, Illinois; Department of Cancer Biology, Loyola University Chicago Stritch School of Medicine, Maywood, Illinois.
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Lyon A, Tripathi R, Meeks C, He D, Wu Y, Liu J, Wang C, Chen J, Zhu H, Mukherjee S, Ganguly S, Plattner R. ABL1/2 and DDR1 Drive MEKi Resistance in NRAS-Mutant Melanomas by Stabilizing RAF/MYC/ETS1 and Promoting RAF Homodimerization. Cancers (Basel) 2023; 15:954. [PMID: 36765910 PMCID: PMC9913232 DOI: 10.3390/cancers15030954] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2022] [Revised: 01/06/2023] [Accepted: 01/11/2023] [Indexed: 02/05/2023] Open
Abstract
Melanomas harboring NRAS mutations are a particularly aggressive and deadly subtype. If patients cannot tolerate or the melanomas are insensitive to immune checkpoint blockade, there are no effective 2nd-line treatment options. Drugs targeting the RAF/MEK/ERK pathway, which are used for BRAF-mutant melanomas, do little to increase progression-free survival (PFS). Here, using both loss-of-function and gain-of-function approaches, we show that ABL1/2 and DDR1 are critical nodes during NRAS-mutant melanoma intrinsic and acquired MEK inhibitor (MEKi) resistance. In some acquired resistance cells, ABL1/2 and DDR1 cooperate to stabilize RAF proteins, activate ERK cytoplasmic and nuclear signaling, repress p27/KIP1 expression, and drive RAF homodimerization. In contrast, other acquired resistance cells depend solely on ABL1/2 for their survival, and are sensitive to highly specific allosteric ABL1/2 inhibitors, which prevent β-catenin nuclear localization and destabilize MYC and ETS1 in an ERK-independent manner. Significantly, targeting ABL1/2 and DDR1 with an FDA-approved anti-leukemic drug, reverses intrinsic MEKi resistance, delays acquisition of acquired resistance, and doubles the survival time in a NRAS-mutant mouse model. These data indicate that repurposing FDA-approved drugs targeting ABL1/2 and DDR1 may be a novel and effective strategy for treating patients with treatment-refractory NRAS-driven melanomas.
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Affiliation(s)
- Anastasia Lyon
- Department of Pharmacology and Nutritional Sciences, College of Medicine, University of Kentucky, Lexington, KY 40536, USA
| | - Rakshamani Tripathi
- Department of Pharmacology and Nutritional Sciences, College of Medicine, University of Kentucky, Lexington, KY 40536, USA
| | - Christina Meeks
- Department of Pharmacology and Nutritional Sciences, College of Medicine, University of Kentucky, Lexington, KY 40536, USA
| | - Daheng He
- Biostatistics and Bioinformatics Shared Resource Facility, College of Medicine, Markey Cancer Center, University of Kentucky, Lexington, KY 40508, USA
| | - Yuanyuan Wu
- Biostatistics and Bioinformatics Shared Resource Facility, College of Medicine, Markey Cancer Center, University of Kentucky, Lexington, KY 40508, USA
| | - Jinpeng Liu
- Biostatistics and Bioinformatics Shared Resource Facility, College of Medicine, Markey Cancer Center, University of Kentucky, Lexington, KY 40508, USA
| | - Chi Wang
- Biostatistics and Bioinformatics Shared Resource Facility, College of Medicine, Markey Cancer Center, University of Kentucky, Lexington, KY 40508, USA
| | - Jing Chen
- Department of Molecular and Cellular Biochemistry, University of Kentucky, Lexington, KY 40536, USA
| | - Haining Zhu
- Department of Molecular and Cellular Biochemistry, University of Kentucky, Lexington, KY 40536, USA
| | - Sujata Mukherjee
- Department of Pharmacology and Nutritional Sciences, College of Medicine, University of Kentucky, Lexington, KY 40536, USA
| | - Saptadwipa Ganguly
- Department of Pharmacology and Nutritional Sciences, College of Medicine, University of Kentucky, Lexington, KY 40536, USA
| | - Rina Plattner
- Department of Pharmacology and Nutritional Sciences, College of Medicine, University of Kentucky, Lexington, KY 40536, USA
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3
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McKernan CM, Khatri A, Hannigan M, Child J, Chen Q, Mayro B, Snyder D, Nicchitta CV, Pendergast AM. ABL kinases regulate translation in HER2+ cells through Y-box-binding protein 1 to facilitate colonization of the brain. Cell Rep 2022; 40:111268. [PMID: 36044842 PMCID: PMC9472557 DOI: 10.1016/j.celrep.2022.111268] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2021] [Revised: 06/20/2022] [Accepted: 08/04/2022] [Indexed: 11/27/2022] Open
Abstract
Patients with human epidermal growth factor receptor 2-positive (HER2+/ERBB2) breast cancer often present with brain metastasis. HER2-targeted therapies have not been successful to treat brain metastases in part due to poor blood-brain barrier (BBB) penetrance and emergence of resistance. Here, we report that Abelson (ABL) kinase allosteric inhibitors improve overall survival and impair HER2+ brain metastatic outgrowth in vivo. Mechanistically, ABL kinases phosphorylate the RNA-binding protein Y-box-binding protein 1 (YB-1). ABL kinase inhibition disrupts binding of YB-1 to the ERBB2 mRNA and impairs translation, leading to a profound decrease in HER2 protein levels. ABL-dependent tyrosine phosphorylation of YB-1 promotes HER2 translation. Notably, loss of YB-1 inhibits brain metastatic outgrowth and impairs expression of a subset of ABL-dependent brain metastatic targets. These data support a role for ABL kinases in the translational regulation of brain metastatic targets through YB-1 and offer a therapeutic target for HER2+ brain metastasis patients.
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Affiliation(s)
- Courtney M McKernan
- Department of Pharmacology and Cancer Biology, Duke University School of Medicine, Durham, NC 27710, USA
| | - Aaditya Khatri
- Department of Pharmacology and Cancer Biology, Duke University School of Medicine, Durham, NC 27710, USA; Department of Medicine, Duke University School of Medicine, Durham, NC 27710, USA
| | - Molly Hannigan
- Department of Cell Biology, Duke University School of Medicine, Durham, NC 27710, USA
| | - Jessica Child
- Department of Cell Biology, Duke University School of Medicine, Durham, NC 27710, USA
| | - Qiang Chen
- Department of Cell Biology, Duke University School of Medicine, Durham, NC 27710, USA
| | - Benjamin Mayro
- Department of Pharmacology and Cancer Biology, Duke University School of Medicine, Durham, NC 27710, USA
| | - David Snyder
- Department of Surgery, Duke University School of Medicine, Durham, NC 27710, USA
| | | | - Ann Marie Pendergast
- Department of Pharmacology and Cancer Biology, Duke University School of Medicine, Durham, NC 27710, USA.
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4
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Montecchini O, Braidotti S, Franca R, Zudeh G, Boni C, Sorio C, Toffoletti E, Rabusin M, Tommasini A, Decorti G, Stocco G. A Novel ELISA-Based Peptide Biosensor Assay for Screening ABL1 Activity in vitro: A Challenge for Precision Therapy in BCR-ABL1 and BCR-ABL1 Like Leukemias. Front Pharmacol 2021; 12:749361. [PMID: 34867354 PMCID: PMC8640483 DOI: 10.3389/fphar.2021.749361] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2021] [Accepted: 10/08/2021] [Indexed: 11/13/2022] Open
Abstract
The pathogenic role of the overactivated ABL1 tyrosine kinase (TK) pathway is well recognized in some forms of BCR-ABL1 like acute lymphoblastic leukemia (ALL); TK inhibitors represent a useful therapeutic choice in these patients who respond poorly to conventional chemotherapy. Here we report a novel peptide biosensor (PABL)-ELISA assay to investigate ABL1 activity in four immortalized leukemic cell lines with different genetic background. The PABL sequence comprises an ABL1 tyrosine (Y) phosphorylation site and a targeting sequence that increases the specificity for ABL1; additional peptides (Y-site-mutated (PABL-F) and fully-phosphorylated (PPHOSPHO-ABL) biosensors) were included in the assay. After incubation with whole cell lysates, average PABL phosphorylation was significantly increased (basal vs. PABL phosphorylation: 6.84 ± 1.46% vs. 32.44 ± 3.25%, p-value < 0.0001, two-way ANOVA, Bonferroni post-test, percentages relative to PPHOSPHO-ABL in each cell line). Cell lines expressing ABL1-chimeric proteins (K562, ALL-SIL) presented the higher TK activity on PABL; a lower signal was instead observed for NALM6 and REH (p < 0.001 and p < 0.05 vs. K562, respectively). Phosphorylation was ABL1-mediated, as demonstrated by the specific inhibition of imatinib (p < 0.001 for K562, NALM6, ALL-SIL and p < 0.01 for REH) in contrast to ruxolitinib (JAK2-inhibitor), and occurred on the ABL1 Y-site, as demonstrated by PABL-F whose phosphorylation was comparable to basal levels. In order to validate this novel PABL-ELISA assay on leukemic cells isolated from patient’s bone marrow aspirates, preliminary analysis on blasts derived from an adult affected by chronic myeloid leukaemia (BCR-ABL1 positive) and a child affected by ALL (BCR-ABL1 negative) were performed. Phosphorylation of PABL was specifically inhibited after the incubation of BCR-ABL1 positive cell lysates with imatinib, but not with ruxolitinib. While requiring further optimization and validation in leukemic blasts to be of clinical interest, the PABL-based ELISA assay provides a novel in vitro tool for screening both the aberrant ABL1 activity in BCR-ABL1 like ALL leukemic cells and their potential response to TK inhibitors.
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Affiliation(s)
- Oksana Montecchini
- Department of Medical, Surgical and Health Sciences, University of Trieste, Trieste, Italy
| | - Stefania Braidotti
- Department of Medical, Surgical and Health Sciences, University of Trieste, Trieste, Italy
| | - Raffaella Franca
- Department of Medical, Surgical and Health Sciences, University of Trieste, Trieste, Italy
| | - Giulia Zudeh
- Department of Life Sciences, University of Trieste, Trieste, Italy
| | - Christian Boni
- Department of Medicine, University of Verona, Verona, Italy
| | - Claudio Sorio
- Department of Medicine, University of Verona, Verona, Italy
| | - Eleonora Toffoletti
- Division of Hematology and Bone Marrow Transplantation, Azienda Ospedaliero-Universitaria, Udine, Italy
| | - Marco Rabusin
- Institute for Maternal and Child Health (I.R.C.C.S) Burlo Garofolo, Trieste, Italy
| | - Alberto Tommasini
- Department of Medical, Surgical and Health Sciences, University of Trieste, Trieste, Italy.,Institute for Maternal and Child Health (I.R.C.C.S) Burlo Garofolo, Trieste, Italy
| | - Giuliana Decorti
- Department of Medical, Surgical and Health Sciences, University of Trieste, Trieste, Italy.,Institute for Maternal and Child Health (I.R.C.C.S) Burlo Garofolo, Trieste, Italy
| | - Gabriele Stocco
- Department of Life Sciences, University of Trieste, Trieste, Italy
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5
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Wu K, Wu H, Lyu W, Kim Y, Furdui CM, Anderson KS, Koleske AJ. Platelet-derived growth factor receptor beta activates Abl2 via direct binding and phosphorylation. J Biol Chem 2021; 297:100883. [PMID: 34144039 PMCID: PMC8259415 DOI: 10.1016/j.jbc.2021.100883] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2021] [Revised: 06/07/2021] [Accepted: 06/14/2021] [Indexed: 11/27/2022] Open
Abstract
Abl family kinases are nonreceptor tyrosine kinases activated by diverse cellular stimuli that regulate cytoskeleton organization, morphogenesis, and adhesion. The catalytic activity of Abl family kinases is tightly regulated in cells by a complex set of intramolecular and intermolecular interactions and post-translational modifications. For example, the platelet-derived growth factor receptor beta (PDGFRβ), important for cell proliferation and chemotaxis, is a potent activator of Abl family kinases. However, the molecular mechanism by which PDGFRβ engages and activates Abl family kinases is not known. We show here that the Abl2 Src homology 2 domain directly binds to phosphotyrosine Y771 in the PDGFRβ cytoplasmic domain. PDGFRβ directly phosphorylates multiple novel sites on the N-terminal half of Abl2, including Y116, Y139, and Y161 within the Src homology 3 domain, and Y299, Y303, and Y310 on the kinase domain. Y116, Y161, Y272, and Y310 are all located at or near the Src homology 3/Src homology 2-kinase linker interface, which helps maintain Abl family kinases in an autoinhibited conformation. We also found that PDGFRβ-mediated phosphorylation of Abl2 in vitro activates Abl2 kinase activity, but mutation of these four tyrosines (Y116, Y161, Y272, and Y310) to phenylalanine abrogated PDGFRβ-mediated activation of Abl2. These findings reveal how PDGFRβ engages and phosphorylates Abl2 leading to activation of the kinase, providing a framework to understand how growth factor receptors engage and activate Abl family kinases.
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Affiliation(s)
- Kuanlin Wu
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, Connecticut, USA
| | - Hanzhi Wu
- Department of Internal Medicine, Section on Molecular Medicine, Wake Forest School of Medicine, Winston-Salem, North Carolina, USA
| | - Wanqing Lyu
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, Connecticut, USA
| | - Youngjoo Kim
- Department of Pharmacology, Yale University, New Haven, Connecticut, USA
| | - Cristina M Furdui
- Department of Internal Medicine, Section on Molecular Medicine, Wake Forest School of Medicine, Winston-Salem, North Carolina, USA
| | - Karen S Anderson
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, Connecticut, USA; Department of Pharmacology, Yale University, New Haven, Connecticut, USA
| | - Anthony J Koleske
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, Connecticut, USA; Department of Neuroscience, Yale University, New Haven, Connecticut, USA.
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6
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Luttman JH, Colemon A, Mayro B, Pendergast AM. Role of the ABL tyrosine kinases in the epithelial-mesenchymal transition and the metastatic cascade. Cell Commun Signal 2021; 19:59. [PMID: 34022881 PMCID: PMC8140471 DOI: 10.1186/s12964-021-00739-6] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2021] [Accepted: 04/16/2021] [Indexed: 12/20/2022] Open
Abstract
The ABL kinases, ABL1 and ABL2, promote tumor progression and metastasis in various solid tumors. Recent reports have shown that ABL kinases have increased expression and/or activity in solid tumors and that ABL inactivation impairs metastasis. The therapeutic effects of ABL inactivation are due in part to ABL-dependent regulation of diverse cellular processes related to the epithelial to mesenchymal transition and subsequent steps in the metastatic cascade. ABL kinases target multiple signaling pathways required for promoting one or more steps in the metastatic cascade. These findings highlight the potential utility of specific ABL kinase inhibitors as a novel treatment paradigm for patients with advanced metastatic disease. Video abstract.
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Affiliation(s)
- Jillian Hattaway Luttman
- Department of Pharmacology and Cancer Biology, Duke University School of Medicine, 308 Research Drive, C-233A LSRC Bldg., P.O. Box 3813, Durham, NC 27710 USA
| | - Ashley Colemon
- Department of Pharmacology and Cancer Biology, Duke University School of Medicine, 308 Research Drive, C-233A LSRC Bldg., P.O. Box 3813, Durham, NC 27710 USA
| | - Benjamin Mayro
- Department of Pharmacology and Cancer Biology, Duke University School of Medicine, 308 Research Drive, C-233A LSRC Bldg., P.O. Box 3813, Durham, NC 27710 USA
| | - Ann Marie Pendergast
- Department of Pharmacology and Cancer Biology, Duke University School of Medicine, 308 Research Drive, C-233A LSRC Bldg., P.O. Box 3813, Durham, NC 27710 USA
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7
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Gu JJ, Hoj J, Rouse C, Pendergast AM. Mesenchymal stem cells promote metastasis through activation of an ABL-MMP9 signaling axis in lung cancer cells. PLoS One 2020; 15:e0241423. [PMID: 33119681 PMCID: PMC7595271 DOI: 10.1371/journal.pone.0241423] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2020] [Accepted: 10/14/2020] [Indexed: 12/26/2022] Open
Abstract
Mesenchymal stem cells (MSCs) are recruited and activated by solid tumors and play a role in tumor progression and metastasis. Here we show that MSCs promote metastasis in a panel of non-small cell lung cancer (NSCLC) cells. MSCs elicit transcriptional alterations in lung cancer cells leading to increased expression of factors implicated in the epithelial-to-mesenchymal transition (EMT) and secreted proteins including matrix metalloproteinase-9 (MMP9). MSCs enhance secretion of enzymatically active MMP9 in a panel of lung adenocarcinoma cells. High expression of MMP9 is linked to low survival rates in lung adenocarcinoma patients. Notably, we found that ABL tyrosine kinases are activated in MSC-primed lung cancer cells and functional ABL kinases are required for MSC-induced MMP9 expression, secretion and proteolytic activity. Importantly, ABL kinases are required for MSC-induced NSCLC metastasis. These data reveal an actionable target for inhibiting MSC-induced metastatic activity of lung adenocarcinoma cells through disruption of an ABL kinase-MMP9 signaling axis activated in MSC-primed lung cancer cells.
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Affiliation(s)
- Jing Jin Gu
- Department of Pharmacology and Cancer Biology, Duke University School of Medicine, Durham, North Carolina, United States of America
| | - Jacob Hoj
- Department of Pharmacology and Cancer Biology, Duke University School of Medicine, Durham, North Carolina, United States of America
| | - Clay Rouse
- Division of Laboratory Animal Resources, Duke University School of Medicine, Durham, North Carolina, United States of America
| | - Ann Marie Pendergast
- Department of Pharmacology and Cancer Biology, Duke University School of Medicine, Durham, North Carolina, United States of America
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8
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Tripathi R, Liu Z, Jain A, Lyon A, Meeks C, Richards D, Liu J, He D, Wang C, Nespi M, Rymar A, Wang P, Wilson M, Plattner R. Combating acquired resistance to MAPK inhibitors in melanoma by targeting Abl1/2-mediated reactivation of MEK/ERK/MYC signaling. Nat Commun 2020; 11:5463. [PMID: 33122628 PMCID: PMC7596241 DOI: 10.1038/s41467-020-19075-3] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2019] [Accepted: 09/29/2020] [Indexed: 12/20/2022] Open
Abstract
Metastatic melanoma remains an incurable disease for many patients due to the limited success of targeted and immunotherapies. BRAF and MEK inhibitors reduce metastatic burden for patients with melanomas harboring BRAF mutations; however, most eventually relapse due to acquired resistance. Here, we demonstrate that ABL1/2 kinase activities and/or expression are potentiated in cell lines and patient samples following resistance, and ABL1/2 drive BRAF and BRAF/MEK inhibitor resistance by inducing reactivation of MEK/ERK/MYC signaling. Silencing/inhibiting ABL1/2 blocks pathway reactivation, and resensitizes resistant cells to BRAF/MEK inhibitors, whereas expression of constitutively active ABL1/2 is sufficient to promote resistance. Significantly, nilotinib (2nd generation ABL1/2 inhibitor) reverses resistance, in vivo, causing prolonged regression of resistant tumors, and also, prevents BRAFi/MEKi resistance from developing in the first place. These data indicate that repurposing the FDA-approved leukemia drug, nilotinib, may be effective for prolonging survival for patients harboring BRAF-mutant melanomas.
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Affiliation(s)
- Rakshamani Tripathi
- Department of Pharmacology and Nutritional Sciences, University of Kentucky College of Medicine, Lexington, KY, 40536, USA
| | - Zulong Liu
- Department of Pharmacology and Nutritional Sciences, University of Kentucky College of Medicine, Lexington, KY, 40536, USA
| | - Aditi Jain
- Department of Pharmacology and Nutritional Sciences, University of Kentucky College of Medicine, Lexington, KY, 40536, USA.,The Jefferson Pancreas, Biliary and Related Cancer Center, Department of Surgery, Sidney Kimmel Cancer Center, Thomas Jefferson University, Philadelphia, PA, USA
| | - Anastasia Lyon
- Department of Pharmacology and Nutritional Sciences, University of Kentucky College of Medicine, Lexington, KY, 40536, USA
| | - Christina Meeks
- Department of Pharmacology and Nutritional Sciences, University of Kentucky College of Medicine, Lexington, KY, 40536, USA
| | - Dana Richards
- Department of Pathology, University of Kentucky College of Medicine, Lexington, KY, 40536, USA
| | - Jinpeng Liu
- Biostatistics and Bioinformatics Shared Resource Facility, Markey Cancer Center, University of Kentucky College of Medicine, Lexington, KY, 40536, USA
| | - Daheng He
- Biostatistics and Bioinformatics Shared Resource Facility, Markey Cancer Center, University of Kentucky College of Medicine, Lexington, KY, 40536, USA
| | - Chi Wang
- Biostatistics and Bioinformatics Shared Resource Facility, Markey Cancer Center, University of Kentucky College of Medicine, Lexington, KY, 40536, USA
| | | | | | - Peng Wang
- Department of Internal Medicine, University of Kentucky, College of Medicine, Lexington, KY, USA
| | - Melissa Wilson
- Department of Medical Oncology, Sidney Kimmel Cancer Center, Thomas Jefferson University, Philadelphia, PA, USA
| | - Rina Plattner
- Department of Pharmacology and Nutritional Sciences, University of Kentucky College of Medicine, Lexington, KY, 40536, USA.
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9
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Hu Y, Lyu W, Lowery LA, Koleske AJ. Regulation of MT dynamics via direct binding of an Abl family kinase. J Cell Biol 2019; 218:3986-3997. [PMID: 31699690 PMCID: PMC6891085 DOI: 10.1083/jcb.201812144] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2019] [Revised: 08/02/2019] [Accepted: 09/30/2019] [Indexed: 12/20/2022] Open
Abstract
Genetic studies revealed that Abl family kinases interact functionally with microtubules, but the mechanism by which Abl kinases regulate microtubules remains unclear. Hu et al. provide the first evidence that the Abl family kinase Abl2 directly binds microtubules to regulate microtubule dynamics. Abl family kinases are essential regulators of cell shape and movement. Genetic studies revealed functional interactions between Abl kinases and microtubules (MTs), but the mechanism by which Abl family kinases regulate MTs remains unclear. Here, we report that Abl2 directly binds to MTs and regulates MT behaviors. Abl2 uses its C-terminal half to bind MTs, an interaction mediated in part through electrostatic binding to tubulin C-terminal tails. Using purified proteins, we found that Abl2 binds growing MTs and promotes MT polymerization and stability. In cells, knockout of Abl2 significantly impairs MT growth, and this defect can be rescued via reexpression of Abl2. Stable reexpression of an Abl2 fragment containing the MT-binding domain alone was sufficient to restore MT growth at the cell edge. These results show Abl2 uses its C-terminal half to bind MTs and directly regulate MT dynamics.
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Affiliation(s)
- Yuhan Hu
- Department of Cell Biology, Yale University, New Haven, CT
| | - Wanqing Lyu
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT
| | | | - Anthony J Koleske
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT .,Department of Neuroscience, Yale University, New Haven, CT
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10
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Tripathi R, Liu Z, Plattner R. EnABLing Tumor Growth and Progression: Recent progress in unraveling the functions of ABL kinases in solid tumor cells. CURRENT PHARMACOLOGY REPORTS 2018; 4:367-379. [PMID: 30746323 PMCID: PMC6368175 DOI: 10.1007/s40495-018-0149-y] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
PURPOSE OF REVIEW The goal of this review is to summarize our current knowledge regarding how ABL family kinases are activated in solid tumors and impact on solid tumor development/progression, with a focus on recent advances in the field. RECENT FINDINGS Although ABL kinases are known drivers of human leukemia, emerging data also implicates the kinases in a large number of solid tumor types where they promote diverse processes such as proliferation, survival, cytoskeletal reorganization, cellular polarity, EMT (epithelial-mesenchymal-transition), metabolic reprogramming, migration, invasion and metastasis via unique signaling pathways. ABL1 and ABL2 appear to have overlapping but also unique roles in driving these processes. In some tumor types, the kinases may act to integrate pro- and anti-proliferative and -invasive signals, and also may serve as a switch during EMT/MET (mesenchymal-epithelial) transitions. CONCLUSIONS Most data indicate that targeting ABL kinases may be effective for reducing tumor growth and preventing metastasis; however, ABL kinases also may have a tumor suppressive role in some tumor types and in some cellular contexts. Understanding the functions of ABL kinases in solid tumors is critical for developing successful clinical trials aimed at targeting ABL kinases for the treatment of solid tumors.
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Affiliation(s)
- Rakshamani Tripathi
- Department of Pharmacology and Nutritional Sciences, University of Kentucky School of Medicine, Lexington, Kentucky 40536
| | - Zulong Liu
- Department of Pharmacology and Nutritional Sciences, University of Kentucky School of Medicine, Lexington, Kentucky 40536
| | - Rina Plattner
- Department of Pharmacology and Nutritional Sciences, University of Kentucky School of Medicine, Lexington, Kentucky 40536
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11
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Tripathi R, Fiore LS, Richards DL, Yang Y, Liu J, Wang C, Plattner R. Abl and Arg mediate cysteine cathepsin secretion to facilitate melanoma invasion and metastasis. Sci Signal 2018; 11:11/518/eaao0422. [PMID: 29463776 DOI: 10.1126/scisignal.aao0422] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
The incidence of melanoma is increasing, particularly in young women, and the disease remains incurable for many because of its aggressive, metastatic nature and its high rate of resistance to conventional, targeted, and immunological agents. Cathepsins are proteases that are critical for melanoma progression and therapeutic resistance. Intracellular cathepsins cleave or degrade proteins that restrict cancer progression, whereas extracellular cathepsins directly cleave the extracellular matrix and activate proinvasive proteases in the tumor microenvironment. Cathepsin secretion is markedly increased in cancer cells. We investigated the signaling pathways leading to increased cathepsin secretion in melanoma cells. We found that the nonreceptor tyrosine kinases Abl and Arg (Abl/Arg) promoted the secretion of cathepsin B and cathepsin L by activating transcription factors (namely, Ets1, Sp1, and NF-κB/p65) that have key roles in the epithelial-mesenchymal transition (EMT), invasion, and therapeutic resistance. In some melanoma cell lines, Abl/Arg promoted the Ets1/p65-induced secretion of cathepsin B and cathepsin L in a kinase-independent manner, whereas in other melanoma lines, Abl/Arg promoted the kinase-dependent, Sp1/Ets1/p65-mediated induction of cathepsin L secretion and the Sp1/p65-mediated induction of cathepsin B secretion. As an indication of clinical relevance, the abundance of mRNAs encoding Abl/Arg, Sp1, Ets1, and cathepsins was positively correlated in primary melanomas, and Abl/Arg-driven invasion in culture and metastasis in vivo required cathepsin secretion. These data suggest that drugs targeting Abl kinases, many of which are FDA-approved, might inhibit cathepsin secretion in some melanomas and potentially other aggressive cancers harboring activated Abl kinases.
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Affiliation(s)
- Rakshamani Tripathi
- Department of Pharmacology and Nutritional Sciences, College of Medicine, University of Kentucky, Lexington, KY 40536, USA
| | - Leann S Fiore
- Department of Pharmacology and Nutritional Sciences, College of Medicine, University of Kentucky, Lexington, KY 40536, USA
| | - Dana L Richards
- Department of Pathology, College of Medicine, University of Kentucky, Lexington, KY 40536, USA
| | - Yuchen Yang
- Department of Statistics, University of Kentucky, Lexington, KY 40536, USA
| | - Jinpeng Liu
- Department of Biostatistics and Markey Cancer Center, University of Kentucky, Lexington, KY 40536, USA
| | - Chi Wang
- Department of Biostatistics and Markey Cancer Center, University of Kentucky, Lexington, KY 40536, USA
| | - Rina Plattner
- Department of Pharmacology and Nutritional Sciences, College of Medicine, University of Kentucky, Lexington, KY 40536, USA.
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12
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Phosphorylation of SOS1 on tyrosine 1196 promotes its RAC GEF activity and contributes to BCR-ABL leukemogenesis. Leukemia 2017; 32:820-827. [PMID: 28819285 PMCID: PMC5739283 DOI: 10.1038/leu.2017.267] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2017] [Revised: 08/07/2017] [Accepted: 08/11/2017] [Indexed: 02/01/2023]
Abstract
Son of Sevenless 1 (SOS1) is a dual guanine nucleotide exchange factor (GEF) that activates the small GTPases RAC and RAS. Although the molecular mechanisms of RAS GEF catalysis have been unveiled, how SOS1 acquires RAC GEF activity and what is the physio-pathological relevance of this activity is much less understood. Here we show that SOS1 is tyrosine phosphorylated on Y1196 by ABL. Phosphorylation of Y1196 controls SOS1 inter-molecular interaction, is required to promote the exchange of nucleotides on RAC in vitro and for platelet-derived growth factor (PDGF) activation of RAC- and RAC-dependent actin remodeling and cell migration. SOS1 is also phosphorylated on Y1196 by BCR-ABL in chronic myelogenous leukemic cells. Importantly, in these cells, SOS1 is required for BCR-ABL-mediated activation of RAC, cell proliferation and transformation in vitro and in a xenograft mouse model. Finally, genetic removal of Sos1 in the bone marrow-derived cells (BMDCs) from Sos1fl/fl mice and infected with BCR-ABL causes a significant delay in the onset of leukemogenesis once BMDCs are injected into recipient, lethally irradiated mice. Thus, SOS1 is required for full transformation and critically contribute to the leukemogenic potential of BCR-ABL.
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13
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Abl kinase regulation by BRAF/ERK and cooperation with Akt in melanoma. Oncogene 2017; 36:4585-4596. [PMID: 28368422 PMCID: PMC5552414 DOI: 10.1038/onc.2017.76] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2016] [Revised: 02/08/2017] [Accepted: 02/22/2017] [Indexed: 12/18/2022]
Abstract
The melanoma incidence continues to increase, and the disease remains incurable for many due to its metastatic nature and high rate of therapeutic resistance. In particular, melanomas harboring BRAFV600E and PTEN mutations often are resistant to current therapies, including BRAF inhibitors (BRAFi) and immune checkpoint inhibitors. Abl kinases (Abl/Arg) are activated in melanomas and drive progression; however, their mechanism of activation has not been established. Here we elucidate a novel link between BRAFV600E/ERK signaling and Abl kinases. We demonstrate that BRAFV600E/ERK play a critical role in binding, phosphorylating and regulating Abl localization and Abl/Arg activation by Src family kinases. Importantly, Abl/Arg activation downstream of BRAFV600E has functional and biological significance, driving proliferation, invasion, as well as switch in epithelial-mesenchymal-transition transcription factor expression, which is known to be critical for melanoma cells to shift between differentiated and invasive states. Finally, we describe findings of high translational significance by demonstrating that Abl/Arg cooperate with PI3K/Akt/PTEN, a parallel pathway that is associated with intrinsic resistance to BRAFi and immunotherapy, as Abl/Arg and Akt inhibitors cooperate to prevent viability, cell cycle progression and in vivo growth of melanomas harboring mutant BRAF/PTEN. Thus, these data not only provide mechanistic insight into Abl/Arg regulation during melanoma development, but also pave the way for the development of new strategies for treating patients with melanomas harboring mutant BRAF/PTEN, which often are refractory to current therapies.
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14
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Gu JJ, Rouse C, Xu X, Wang J, Onaitis MW, Pendergast AM. Inactivation of ABL kinases suppresses non-small cell lung cancer metastasis. JCI Insight 2016; 1:e89647. [PMID: 28018973 DOI: 10.1172/jci.insight.89647] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Current therapies to treat non-small cell lung carcinoma (NSCLC) have proven ineffective owing to transient, variable, and incomplete responses. Here we show that ABL kinases, ABL1 and ABL2, promote metastasis of lung cancer cells harboring EGFR or KRAS mutations. Inactivation of ABL kinases suppresses NSCLC metastasis to brain and bone, and other organs. ABL kinases are required for expression of prometastasis genes. Notably, ABL1 and ABL2 depletion impairs extravasation of lung adenocarcinoma cells into the lung parenchyma. We found that ABL-mediated activation of the TAZ and β-catenin transcriptional coactivators is required for NSCLC metastasis. ABL kinases activate TAZ and β-catenin by decreasing their interaction with the β-TrCP ubiquitin ligase, leading to increased protein stability. High-level expression of ABL1, ABL2, and a subset of ABL-dependent TAZ- and β-catenin-target genes correlates with shortened survival of lung adenocarcinoma patients. Thus, ABL-specific allosteric inhibitors might be effective to treat metastatic lung cancer with an activated ABL pathway signature.
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Affiliation(s)
- Jing Jin Gu
- Department of Pharmacology and Cancer Biology
| | | | - Xia Xu
- Department of Pharmacology and Cancer Biology
| | - Jun Wang
- Department of Pharmacology and Cancer Biology
| | - Mark W Onaitis
- Department of Surgery, Duke University School of Medicine, Durham, North Carolina, USA.,Department of Surgery, University of California, San Diego, San Diego, California, USA
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15
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Wetzel DM, Rhodes EL, Li S, McMahon-Pratt D, Koleske AJ. The Src kinases Hck, Fgr and Lyn activate Arg to facilitate IgG-mediated phagocytosis and Leishmania infection. J Cell Sci 2016; 129:3130-43. [PMID: 27358479 DOI: 10.1242/jcs.185595] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2016] [Accepted: 06/23/2016] [Indexed: 12/19/2022] Open
Abstract
Leishmaniasis is a devastating disease that disfigures or kills nearly two million people each year. Establishment and persistence of infection by the obligate intracellular parasite Leishmania requires repeated uptake by macrophages and other phagocytes. Therefore, preventing uptake could be a novel therapeutic strategy for leishmaniasis. Amastigotes, the life cycle stage found in the human host, bind Fc receptors and enter macrophages primarily through immunoglobulin-mediated phagocytosis. However, the host machinery that mediates amastigote uptake is poorly understood. We have previously shown that the Arg (also known as Abl2) non-receptor tyrosine kinase facilitates L. amazonensis amastigote uptake by macrophages. Using small-molecule inhibitors and primary macrophages lacking specific Src family kinases, we now demonstrate that the Hck, Fgr and Lyn kinases are also necessary for amastigote uptake by macrophages. Src-mediated Arg activation is required for efficient uptake. Interestingly, the dual Arg and Src kinase inhibitor bosutinib, which is approved to treat cancer, not only decreases amastigote uptake, but also significantly reduces disease severity and parasite burden in Leishmania-infected mice. Our results suggest that leishmaniasis could potentially be treated with host-cell-active agents such as kinase inhibitors.
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Affiliation(s)
- Dawn M Wetzel
- Department of Pediatrics, Yale University, New Haven, CT 06520, USA
| | - Emma L Rhodes
- Department of Pediatrics, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Shaoguang Li
- Department of Medicine, University of Massachusetts Medical School, Worcester, MA 01605, USA
| | - Diane McMahon-Pratt
- Department of Epidemiology of Microbial Disease, Yale School of Public Health, New Haven, CT 06520, USA
| | - Anthony J Koleske
- Department of Molecular Biochemistry and Biophysics, Yale University, CT 06520, USA Department of Neuroscience, Yale University, New Haven, CT 06520, USA
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16
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Li R, Knight JF, Park M, Pendergast AM. Abl Kinases Regulate HGF/Met Signaling Required for Epithelial Cell Scattering, Tubulogenesis and Motility. PLoS One 2015; 10:e0124960. [PMID: 25946048 PMCID: PMC4422589 DOI: 10.1371/journal.pone.0124960] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2015] [Accepted: 03/19/2015] [Indexed: 12/16/2022] Open
Abstract
Tight regulation of receptor tyrosine kinases (RTKs) is crucial for normal development and homeostasis. Dysregulation of RTKs signaling is associated with diverse pathological conditions including cancer. The Met RTK is the receptor for hepatocyte growth factor (HGF) and is dysregulated in numerous human tumors. Here we show that Abl family of non-receptor tyrosine kinases, comprised of Abl (ABL1) and Arg (ABL2), are activated downstream of the Met receptor, and that inhibition of Abl kinases dramatically suppresses HGF-induced cell scattering and tubulogenesis. We uncover a critical role for Abl kinases in the regulation of HGF/Met-dependent RhoA activation and RhoA-mediated actomyosin contractility and actin cytoskeleton remodeling in epithelial cells. Moreover, treatment of breast cancer cells with Abl inhibitors markedly decreases Met-driven cell migration and invasion. Notably, expression of a transforming mutant of the Met receptor in the mouse mammary epithelium results in hyper-activation of both Abl and Arg kinases. Together these data demonstrate that Abl kinases link Met activation to Rho signaling and Abl kinases are required for Met-dependent cell scattering, tubulogenesis, migration, and invasion. Thus, inhibition of Abl kinases might be exploited for the treatment of cancers driven by hyperactivation of HGF/Met signaling.
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Affiliation(s)
- Ran Li
- Department of Pharmacology and Cancer Biology, Duke University School of Medicine, Durham, North Carolina, United States of America
| | | | - Morag Park
- Goodman Cancer Research Centre, McGill University, Montreal, QC, Canada
- Departments of Biochemistry and Oncology, McGill University, Montreal, QC, Canada
| | - Ann Marie Pendergast
- Department of Pharmacology and Cancer Biology, Duke University School of Medicine, Durham, North Carolina, United States of America
- * E-mail:
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17
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de Oliveira GAP, Rangel LP, Costa DC, Silva JL. Misfolding, Aggregation, and Disordered Segments in c-Abl and p53 in Human Cancer. Front Oncol 2015; 5:97. [PMID: 25973395 PMCID: PMC4413674 DOI: 10.3389/fonc.2015.00097] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2015] [Accepted: 04/10/2015] [Indexed: 01/31/2023] Open
Abstract
The current understanding of the molecular mechanisms that lead to cancer is not sufficient to explain the loss or gain of function in proteins related to tumorigenic processes. Among them, more than 100 oncogenes, 20-30 tumor-suppressor genes, and hundreds of genes participating in DNA repair and replication have been found to play a role in the origins of cancer over the last 25 years. The phosphorylation of serine, threonine, or tyrosine residues is a critical step in cellular growth and development and is achieved through the tight regulation of protein kinases. Phosphorylation plays a major role in eukaryotic signaling as kinase domains are found in 2% of our genes. The deregulation of kinase control mechanisms has disastrous consequences, often leading to gains of function, cell transformation, and cancer. The c-Abl kinase protein is one of the most studied targets in the fight against cancer and is a hotspot for drug development because it participates in several solid tumors and is the hallmark of chronic myelogenous leukemia. Tumor suppressors have the opposite effects. Their fundamental role in the maintenance of genomic integrity has awarded them a role as the guardians of DNA. Among the tumor suppressors, p53 is the most studied. The p53 protein has been shown to be a transcription factor that recognizes and binds to specific DNA response elements and activates gene transcription. Stress triggered by ionizing radiation or other mutagenic events leads to p53 phosphorylation and cell-cycle arrest, senescence, or programed cell death. The p53 gene is the most frequently mutated gene in cancer. Mutations in the DNA-binding domain are classified as class I or class II depending on whether substitutions occur in the DNA contact sites or in the protein core, respectively. Tumor-associated p53 mutations often lead to the loss of protein function, but recent investigations have also indicated gain-of-function mutations. The prion-like aggregation of mutant p53 is associated with loss-of-function, dominant-negative, and gain-of-function effects. In the current review, we focused on the most recent insights into the protein structure and function of the c-Abl and p53 proteins that will provide us guidance to understand the loss and gain of function of these misfolded tumor-associated proteins.
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Affiliation(s)
- Guilherme A. P. de Oliveira
- Programa de Biologia Estrutural, Instituto de Bioquímica Médica Leopoldo de Meis, Instituto Nacional de Biologia Estrutural e Bioimagem, Centro Nacional de Ressonância Magnética Nuclear Jiri Jonas, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Luciana P. Rangel
- Programa de Biologia Estrutural, Instituto de Bioquímica Médica Leopoldo de Meis, Instituto Nacional de Biologia Estrutural e Bioimagem, Centro Nacional de Ressonância Magnética Nuclear Jiri Jonas, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
- Faculdade de Farmácia, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Danielly C. Costa
- Programa de Biologia Estrutural, Instituto de Bioquímica Médica Leopoldo de Meis, Instituto Nacional de Biologia Estrutural e Bioimagem, Centro Nacional de Ressonância Magnética Nuclear Jiri Jonas, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Jerson L. Silva
- Programa de Biologia Estrutural, Instituto de Bioquímica Médica Leopoldo de Meis, Instituto Nacional de Biologia Estrutural e Bioimagem, Centro Nacional de Ressonância Magnética Nuclear Jiri Jonas, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
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18
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Tao W, Leng X, Chakraborty SN, Ma H, Arlinghaus RB. c-Abl activates janus kinase 2 in normal hematopoietic cells. J Biol Chem 2014; 289:21463-72. [PMID: 24923444 DOI: 10.1074/jbc.m114.554501] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Jak2 is involved in cytokine growth factor-stimulated signal transduction, but the mechanism of its activation is largely unknown. Here, we investigated Jak2 activation in a normal hematopoietic cell line, 32D mouse myeloid cells. The bimolecular fluorescence complementation studies showed that c-Abl formed a stable complex with Jak2 in live cells. Co-immunoprecipitation results showed that c-Abl bound to the βc chain of IL-3/IL-5/GM-CSF receptors. The kinase activities of both c-Abl and Jak2 were stimulated by IL-3 in 32D cells. Decreasing c-Abl protein expression in 32D cells by inducible shRNA decreased Jak2 activity and resulted in the failure of Jak2 activation in response to IL-3. Treatment of IL-3 and serum-starved 32D cells with 1 μM imatinib mysylate inhibited IL-3 stimulated kinase activities of both c-Abl and Jak2. In addition, the kinase-deficient Bcr-Abl mutant (p210K1172R) was defective for activation of Jak2 in 32D cells and impaired IL-3 independent growth, which was rescued by overexpression of c-Abl (+Abl). IL-3 efficiently inhibited apoptosis of 32Dp210K/R+Abl cells induced by imatinib mysylate but not Jak2 kinase inhibitor TG101209. In summary, our findings provide evidence that the kinase function of c-Abl and its C-terminal CT4 region is crucial for its interaction with Jak2 and its activation. c-Abl kinase activity induced by IL-3 is required for IL-3-stimulated Jak2 and Jak1 activation. Our findings reveal a novel regulatory role of c-Abl in Jak2 activation induced by IL-3 cytokine growth factor in 32D hematopoietic cells.
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Affiliation(s)
- Wenjing Tao
- From the Department of Translational Molecular Pathology, University of Texas M.D. Anderson Cancer Center, Houston, Texas 77030
| | - Xiaohong Leng
- From the Department of Translational Molecular Pathology, University of Texas M.D. Anderson Cancer Center, Houston, Texas 77030
| | - Sandip N Chakraborty
- From the Department of Translational Molecular Pathology, University of Texas M.D. Anderson Cancer Center, Houston, Texas 77030
| | - Helen Ma
- From the Department of Translational Molecular Pathology, University of Texas M.D. Anderson Cancer Center, Houston, Texas 77030
| | - Ralph B Arlinghaus
- From the Department of Translational Molecular Pathology, University of Texas M.D. Anderson Cancer Center, Houston, Texas 77030
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19
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Demoulin JB, Essaghir A. PDGF receptor signaling networks in normal and cancer cells. Cytokine Growth Factor Rev 2014; 25:273-83. [DOI: 10.1016/j.cytogfr.2014.03.003] [Citation(s) in RCA: 165] [Impact Index Per Article: 16.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2014] [Accepted: 03/10/2014] [Indexed: 01/05/2023]
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20
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Nicolay NH, Sommer E, Perez RL, Wirkner U, Bostel T, Ho AD, Lahn M, Debus J, Saffrich R, Huber PE. Mesenchymal stem cells are sensitive to treatment with kinase inhibitors and ionizing radiation. Strahlenther Onkol 2014; 190:1037-45. [DOI: 10.1007/s00066-014-0686-1] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2014] [Accepted: 04/28/2014] [Indexed: 10/25/2022]
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21
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Stephens RS, Servinsky LE, Rentsendorj O, Kolb TM, Pfeifer A, Pearse DB. Protein kinase G increases antioxidant function in lung microvascular endothelial cells by inhibiting the c-Abl tyrosine kinase. Am J Physiol Cell Physiol 2014; 306:C559-69. [PMID: 24401847 DOI: 10.1152/ajpcell.00375.2012] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Oxidant injury contributes to acute lung injury (ALI). We previously reported that activation of protein kinase GI (PKGI) posttranscriptionally increased the key antioxidant enzymes catalase and glutathione peroxidase 1 (Gpx-1) and attenuated oxidant-induced cytotoxicity in mouse lung microvascular endothelial cells (MLMVEC). The present studies tested the hypothesis that the antioxidant effect of PKGI is mediated via inhibition of the c-Abl tyrosine kinase. We found that activation of PKGI with the cGMP analog 8pCPT-cGMP inhibited c-Abl activity and decreased c-Abl expression in wild-type but not PKGI(-/-) MLMVEC. Treatment of wild-type MLMVEC with atrial natriuretic peptide also inhibited c-Abl activation. Moreover, treatment of MLMVEC with the c-Abl inhibitor imatinib increased catalase and GPx-1 protein in a posttranscriptional fashion. In imatinib-treated MLMVEC, there was no additional effect of 8pCPT-cGMP on catalase or GPx-1. The imatinib-induced increase in antioxidant proteins was associated with an increase in extracellular H2O2 scavenging by MLMVEC, attenuation of oxidant-induced endothelial barrier dysfunction, and prevention of oxidant-induced endothelial cell death. Finally, in the isolated perfused lung, imatinib prevented oxidant-induced endothelial toxicity. We conclude that cGMP, through activation of PKGI, inhibits c-Abl, leading to increased key antioxidant enzymes and resistance to lung endothelial oxidant injury. Inhibition of c-Abl by active PKGI may be the downstream mechanism underlying PKGI-mediated antioxidant signaling. Tyrosine kinase inhibitors may represent a novel therapeutic approach in oxidant-induced ALI.
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Affiliation(s)
- R Scott Stephens
- Division of Pulmonary and Critical Care Medicine, Department of Medicine, Johns Hopkins University, Baltimore, Maryland, and
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22
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Chislock EM, Pendergast AM. Abl family kinases regulate endothelial barrier function in vitro and in mice. PLoS One 2013; 8:e85231. [PMID: 24367707 PMCID: PMC3868616 DOI: 10.1371/journal.pone.0085231] [Citation(s) in RCA: 66] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2013] [Accepted: 11/25/2013] [Indexed: 12/22/2022] Open
Abstract
The maintenance of endothelial barrier function is essential for normal physiology, and increased vascular permeability is a feature of a wide variety of pathological conditions, leading to complications including edema and tissue damage. Use of the pharmacological inhibitor imatinib, which targets the Abl family of non-receptor tyrosine kinases (Abl and Arg), as well as other tyrosine kinases including the platelet-derived growth factor receptor (PDGFR), Kit, colony stimulating factor 1 receptor (CSF1R), and discoidin domain receptors, has shown protective effects in animal models of inflammation, sepsis, and other pathologies characterized by enhanced vascular permeability. However, the imatinib targets involved in modulation of vascular permeability have not been well-characterized, as imatinib inhibits multiple tyrosine kinases not only in endothelial cells and pericytes but also immune cells important for disorders associated with pathological inflammation and abnormal vascular permeability. In this work we employ endothelial Abl knockout mice to show for the first time a direct role for Abl in the regulation of vascular permeability in vivo. Using both Abl/Arg-specific pharmacological inhibition and endothelial Abl knockout mice, we demonstrate a requirement for Abl kinase activity in the induction of endothelial permeability by vascular endothelial growth factor both in vitro and in vivo. Notably, Abl kinase inhibition also impaired endothelial permeability in response to the inflammatory mediators thrombin and histamine. Mechanistically, we show that loss of Abl kinase activity was accompanied by activation of the barrier-stabilizing GTPases Rac1 and Rap1, as well as inhibition of agonist-induced Ca2+ mobilization and generation of acto-myosin contractility. In all, these findings suggest that pharmacological targeting of the Abl kinases may be capable of inhibiting endothelial permeability induced by a broad range of agonists and that use of Abl kinase inhibitors may have potential for the treatment of disorders involving pathological vascular leakage.
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Affiliation(s)
- Elizabeth M. Chislock
- Department of Pharmacology and Cancer Biology, Duke University School of Medicine, Durham, North Carolina, United States of America
| | - Ann Marie Pendergast
- Department of Pharmacology and Cancer Biology, Duke University School of Medicine, Durham, North Carolina, United States of America
- * E-mail:
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Hayes KE, Walk EL, Ammer AG, Kelley LC, Martin KH, Weed SA. Ableson kinases negatively regulate invadopodia function and invasion in head and neck squamous cell carcinoma by inhibiting an HB-EGF autocrine loop. Oncogene 2013; 32:4766-77. [PMID: 23146907 PMCID: PMC3896120 DOI: 10.1038/onc.2012.513] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2012] [Revised: 09/24/2012] [Accepted: 09/24/2012] [Indexed: 01/24/2023]
Abstract
Head and neck squamous cell carcinoma (HNSCC) has a proclivity for locoregional invasion. HNSCC mediates invasion in part through invadopodia-based proteolysis of the extracellular matrix (ECM). Activation of Src, Erk1/2, Abl and Arg downstream of epidermal growth factor receptor (EGFR) modulates invadopodia activity through phosphorylation of the actin regulatory protein cortactin. In MDA-MB-231 breast cancer cells, Abl and Arg function downstream of Src to phosphorylate cortactin, promoting invadopodia ECM degradation activity and thus assigning a pro-invasive role for Ableson kinases. We report that Abl kinases have an opposite, negative regulatory role in HNSCC where they suppress invadopodia and tumor invasion. Impairment of Abl expression or Abl kinase activity with imatinib mesylate enhanced HNSCC matrix degradation and 3D collagen invasion, functions that were impaired in MDA-MB-231. HNSCC lines with elevated EGFR and Src activation did not contain increased Abl or Arg kinase activity, suggesting that Src could bypass Abl/Arg to phosphorylate cortactin and promote invadopodia ECM degradation. Src-transformed Abl(-/-)/Arg(-/-) fibroblasts produced ECM degrading invadopodia containing pY421 cortactin, indicating that Abl/Arg are dispensable for invadopodia function in this system. Imatinib-treated HNSCC cells had increased EGFR, Erk1/2 and Src activation, enhancing cortactin pY421 and pS405/418 required for invadopodia function. Imatinib stimulated shedding of the EGFR ligand heparin-binding EGF-like growth factor (HB-EGF) from HNSCC cells, where soluble HB-EGF enhanced invadopodia ECM degradation in HNSCC but not in MDA-MB-231. HNSCC cells treated with inhibitors of the EGFR-invadopodia pathway indicated that EGFR and Src are required for invadopodia function. Collectively, our results indicate that Abl kinases negatively regulate HNSCC invasive processes through suppression of an HB-EGF autocrine loop responsible for activating a EGFR-Src-cortactin cascade, in contrast to the invasion promoting functions of Abl kinases in breast and other cancer types. Our results provide mechanistic support for recent failed HNSCC clinical trials utilizing imatinib.
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Affiliation(s)
- Karen E. Hayes
- Department of Neurobiology and Anatomy, Program in Cancer Cell Biology, Mary Babb Randolph Cancer Center, West Virginia University, Morgantown, West Virginia, 26506-9300, United States of America
| | - Elyse L. Walk
- Department of Neurobiology and Anatomy, Program in Cancer Cell Biology, Mary Babb Randolph Cancer Center, West Virginia University, Morgantown, West Virginia, 26506-9300, United States of America
| | - Amanda Gatesman Ammer
- Department of Neurobiology and Anatomy, Program in Cancer Cell Biology, Mary Babb Randolph Cancer Center, West Virginia University, Morgantown, West Virginia, 26506-9300, United States of America
| | | | - Karen H. Martin
- Department of Neurobiology and Anatomy, Program in Cancer Cell Biology, Mary Babb Randolph Cancer Center, West Virginia University, Morgantown, West Virginia, 26506-9300, United States of America
| | - Scott A. Weed
- Department of Neurobiology and Anatomy, Program in Cancer Cell Biology, Mary Babb Randolph Cancer Center, West Virginia University, Morgantown, West Virginia, 26506-9300, United States of America
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24
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Ghosh-Choudhury N, Mandal CC, Das F, Ganapathy S, Ahuja S, Ghosh Choudhury G. c-Abl-dependent molecular circuitry involving Smad5 and phosphatidylinositol 3-kinase regulates bone morphogenetic protein-2-induced osteogenesis. J Biol Chem 2013; 288:24503-17. [PMID: 23821550 DOI: 10.1074/jbc.m113.455733] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023] Open
Abstract
Skeletal remodeling consists of timely formation and resorption of bone by osteoblasts and osteoclasts in a quantitative manner. Patients with chronic myeloid leukemia receiving inhibitors of c-Abl tyrosine kinase often show reduced bone remodeling due to impaired osteoblast and osteoclast function. BMP-2 plays a significant role in bone generation and resorption by contributing to the formation of mature osteoblasts and osteoclasts. The effects of c-Abl on BMP-2-induced bone remodeling and the underlying mechanisms are not well studied. Using a pharmacological inhibitor and expression of a dominant negative mutant of c-Abl, we show an essential role of this tyrosine kinase in the development of bone nodules containing mature osteoblasts and formation of multinucleated osteoclasts in response to BMP-2. Calvarial osteoblasts prepared from c-Abl null mice showed the absolute requirement of this tyrosine kinase in maturation of osteoblasts and osteoclasts. Activation of phosphatidylinositol 3-kinase (PI 3-kinase)/Akt signaling by BMP-2 leads to osteoblast differentiation. Remarkably, inhibition of c-Abl significantly suppressed BMP-2-stimulated PI 3-kinase activity and its downstream Akt phosphorylation. Interestingly, c-Abl regulated BMP-2-induced osteoclastogenic CSF-1 expression. More importantly, we identified the requirements of c-Abl in BMP-2 autoregulation and the expressions of alkaline phosphatase and osterix that are necessary for osteoblast differentiation. c-Abl contributed to BMP receptor-specific Smad-dependent transcription of CSF-1, osterix, and BMP-2. Finally, c-Abl associates with BMP receptor IA and regulates phosphorylation of Smad in response to BMP-2. We propose that activation of c-Abl is an important step, which induces into two signaling pathways involving noncanonical PI 3-kinase and canonical Smads to integrate BMP-2-induced osteogenesis.
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Affiliation(s)
- Nandini Ghosh-Choudhury
- Veterans Affairs Research, South Texas Veterans Health Care System, San Antonio, Texas 78229, USA.
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25
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Hutterer C, Wandinger SK, Wagner S, Müller R, Stamminger T, Zeitträger I, Godl K, Baumgartner R, Strobl S, Marschall M. Profiling of the kinome of cytomegalovirus-infected cells reveals the functional importance of host kinases Aurora A, ABL and AMPK. Antiviral Res 2013; 99:139-48. [PMID: 23648710 DOI: 10.1016/j.antiviral.2013.04.017] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2012] [Revised: 04/19/2013] [Accepted: 04/24/2013] [Indexed: 12/20/2022]
Abstract
Human cytomegalovirus infection can lead to life-threatening clinical manifestations particularly in the immunocompromised host. Current therapy options face severe limitations leading to a continued search for alternative drug candidates. Viral replication is dependent on a balanced interaction between viral and cellular proteins. Especially protein kinases are important regulators of virus-host interaction indicated by remarkable kinome alterations induced upon HCMV infection. Here we report a novel approach of kinome profiling with an outcome that suggests an important role of specific cellular protein kinases, such as AMPK, ABL2 and Aurora A. Inhibition of AMPK and ABL kinases showed a significant reduction, whereas inhibition of Aurora A kinase led to a slight activation of HCMV replication, as measured in a GFP reporter-based replication assay. Furthermore, analysis of the mode of antiviral action suggested a substantial benefit for the efficiency of viral replication at the immediate early (AMPK) or early-late (ABL) phases of HCMV gene expression. In contrast, inhibition of Aurora A kinase promoted an enhancement of viral early-late gene expression, suggesting a putative role of Aurora A signaling in host defense. Thus, the combined data provide new information on host cell kinases involved in viral replication and uncovered potential targets for future antiviral strategies.
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Affiliation(s)
- Corina Hutterer
- Institute for Clinical and Molecular Virology, University of Erlangen-Nuremberg, Erlangen, Germany.
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26
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Zhao H, Chen MS, Lo YH, Waltz SE, Wang J, Ho PC, Vasiliauskas J, Plattner R, Wang YL, Wang SC. The Ron receptor tyrosine kinase activates c-Abl to promote cell proliferation through tyrosine phosphorylation of PCNA in breast cancer. Oncogene 2013; 33:1429-37. [PMID: 23542172 DOI: 10.1038/onc.2013.84] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2012] [Revised: 12/12/2012] [Accepted: 01/11/2013] [Indexed: 12/14/2022]
Abstract
Multiple growth pathways lead to enhanced proliferation in malignant cells. However, how the core machinery of DNA replication is regulated by growth signaling remains largely unclear. The sliding clamp proliferating cell nuclear antigen (PCNA) is an indispensable component of the DNA machinery responsible for replicating the genome and maintaining genomic integrity. We previously reported that epidermal growth factor receptor (EGFR) triggered tyrosine 211 (Y211) phosphorylation of PCNA, which in turn stabilized PCNA on chromatin to promote cell proliferation. Here we show that the phosphorylation can also be catalyzed by the non-receptor tyrosine kinase c-Abl. We further demonstrate that, in the absence of EGFR, signaling to PCNA can be attained through the activation of the Ron receptor tyrosine kinase and the downstream non-receptor tyrosine kinase c-Abl. We show that Ron and c-Abl form a complex, and that activation of Ron by its ligand, hepatocyte growth factor-like protein (HGFL), stimulates c-Abl kinase activity, which in turn directly phosphorylates PCNA at Y211 and leads to an increased level of chromatin-associated PCNA. Correspondingly, HGFL-induced Ron activation resulted in Y211 phosphorylation of PCNA while silencing of c-Abl blocked this effect. We show that c-Abl and Y211 phosphorylation of PCNA is an important axis downstream of Ron, which is required for cell proliferation. Treatment with a specific peptide that inhibits Y211 phosphorylation of PCNA or with the c-Abl pharmacological inhibitor imatinib suppressed HGFL-induced cell proliferation. Our findings identify the pathway of Ron-c-Abl-PCNA as a mechanism of oncogene-induced cell proliferation, with potentially important implications for development of combination therapy of breast cancer.
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Affiliation(s)
- H Zhao
- Department of Cancer Biology, University of Cincinnati College of Medicine, Cincinnati, OH, USA
| | - M-S Chen
- Department of Cancer Biology, University of Cincinnati College of Medicine, Cincinnati, OH, USA
| | - Y-H Lo
- Department of Cancer Biology, University of Cincinnati College of Medicine, Cincinnati, OH, USA
| | - S E Waltz
- 1] Department of Cancer Biology, University of Cincinnati College of Medicine, Cincinnati, OH, USA [2] Cincinnati Veterans Affairs Medical Center, Cincinnati, OH, USA
| | - J Wang
- Department of Pathology and Laboratory Medicine, University of Cincinnati Medical Center, Cincinnati, OH, USA
| | - P-C Ho
- Department of Cancer Biology, University of Cincinnati College of Medicine, Cincinnati, OH, USA
| | - J Vasiliauskas
- Department of Cancer Biology, University of Cincinnati College of Medicine, Cincinnati, OH, USA
| | - R Plattner
- Department of Molecular and Biomedical Pharmacology, University of Kentucky School of Medicine, Lexington, KY, USA
| | - Y-L Wang
- Department of Cancer Biology, University of Cincinnati College of Medicine, Cincinnati, OH, USA
| | - S-C Wang
- Department of Cancer Biology, University of Cincinnati College of Medicine, Cincinnati, OH, USA
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27
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Hossain S, Dubielecka PM, Sikorski AF, Birge RB, Kotula L. Crk and ABI1: binary molecular switches that regulate abl tyrosine kinase and signaling to the cytoskeleton. Genes Cancer 2012; 3:402-13. [PMID: 23226578 DOI: 10.1177/1947601912460051] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
The nonreceptor tyrosine kinases Abl and Arg are among the most well-characterized tyrosine kinases in the human genome. The activation of Abl by N-terminal fusions with Bcr (Bcr-Abl) or Gag (v-Abl) is responsible for chronic myeloid leukemia or Ph+ acute lymphoblastic leukemia and mouse leukemia virus, respectively. In addition, aberrant Abl and Arg activation downstream of several oncogenic growth factor receptors contributes to the development and progression of a variety of human cancers, often associated with poor clinical outcome, drug resistance, and tumor invasion and metastasis. Abl activation can occur by a variety of mechanisms that include domain interactions involving structural remodeling of autoinhibited conformations as well as direct phosphorylation by upstream kinases and phosphatases. Constitutive activation of Abl plays a significant role in regulating the actin cytoskeleton by modulating cell adhesion, motility, and invadopodia. This review addresses the role of Abl and Arg in tumor progression with particular emphasis on the roles of Crk and Abi1 adapter proteins as distinct molecular switches for Abl transactivation. These insights, combined with new insights into the structure of these kinases, provide the rationale to envision that Crk and Abi1 fine-tune Abl regulation to control signaling to the cytoskeleton.
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Affiliation(s)
- Sajjad Hossain
- New York State Institute for Basic Research in Developmental Disabilities, Staten Island, NY, USA ; Current address: Stony Brook University, Stony Brook, NY, USA
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28
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Abstract
Although c-Abl and Arg non-receptor tyrosine kinases are well known for driving leukemia development, their role in solid tumors has not been appreciated until recently. Accumulating evidence now indicates that c-Abl and/or Arg are activated in some solid tumor cell lines via unique mechanisms that do not involve gene mutation/translocation, and c-Abl/Arg activation promotes matrix degradation, invasion, proliferation, tumorigenesis, and/or metastasis, depending on the tumor type. However, some data suggest that c-Abl also may suppress invasion, proliferation, and tumorigenesis in certain cell contexts. Thus, c-Abl/Arg may serve as molecular switches that suppress proliferation and invasion in response to some stimuli (e.g., ephrins) or when inactive/regulated, or as promote invasion and proliferation in response to other signals (e.g., activated growth factor receptors, loss of inhibitor expression), which induce sustained activation. Clearly, more data are required to determine the extent and prevalence of c-Abl/Arg activation in primary tumors and during progression, and additional animal studies are needed to substantiate in vitro findings. Furthermore, c-Abl/Arg inhibitors have been used in numerous solid tumor clinical trials; however, none of these trials were restricted to patients whose tumors expressed highly activated c-Abl/Arg (targeted trial). Targeted trials are critical for determining whether c-Abl/Arg inhibitors can be effective treatment options for patients whose tumors are driven by c-Abl/Arg.
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29
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Ball SG, Shuttleworth A, Kielty CM. Inhibition of platelet-derived growth factor receptor signaling regulates Oct4 and Nanog expression, cell shape, and mesenchymal stem cell potency. Stem Cells 2012; 30:548-60. [PMID: 22213560 PMCID: PMC3537888 DOI: 10.1002/stem.1015] [Citation(s) in RCA: 59] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Defining the signaling mechanisms that regulate the fate of adult stem cells is an essential step toward their use in regenerative medicine. Platelet-derived growth factor receptor (PDGFR) signaling plays a crucial role in specifying mesenchymal stem cell (MSC) commitment to mesenchymal lineages. Based on the hypothesis that selective inhibition of signaling pathways involved in differentiation may increase stem cell potency, we examined the role of PDGFR signaling in controlling the fate of human MSCs. Using a small molecular PDGFR inhibitor that induced MSCs toward a more rounded shape, expression of Oct4 and Nanog were markedly upregulated. In these PDGFR inhibitor-treated MSCs, Oct4 and Nanog expression and cell shape were regulated by janus kinase (JAK), MAPK kinase (MEK), and epidermal growth factor receptor (EGFR) signaling. Under defined differentiation conditions, these PDGFR-inhibited MSCs expressed definitive endodermal, ectodermal, and mesodermal markers. We also confirmed that depletion of individual PDGF receptors upregulated expression of Oct4A and Nanog. This study identifies PDGFR signaling as a key regulator of Oct4 and Nanog expression and of MSC potency. Thus, inhibiting these specific receptor tyrosine kinases, which play essential roles in tissue formation, offers a novel approach to unlock the therapeutic capacity of MSCs. STEM CELLS 2012;30:548–560
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Affiliation(s)
- Stephen G Ball
- Wellcome Trust Centre for Cell-Matrix Research, Faculty of Life Sciences, University of Manchester, Manchester, UK
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30
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Bonacci G, Fletcher J, Devani M, Dwivedi H, Keller R, Chang C. The cytoplasmic tyrosine kinase Arg regulates gastrulation via control of actin organization. Dev Biol 2012; 364:42-55. [PMID: 22305799 DOI: 10.1016/j.ydbio.2012.01.008] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2011] [Accepted: 01/11/2012] [Indexed: 10/14/2022]
Abstract
Coordinated cell movements are crucial for vertebrate gastrulation and are controlled by multiple signals. Although many factors are shown to mediate non-canonical Wnt pathways to regulate cell polarity and intercalation during gastrulation, signaling molecules acting in other pathways are less investigated and the connections between various signals and cytoskeleton are not well understood. In this study, we show that the cytoplasmic tyrosine kinase Arg modulates gastrulation movements through control of actin remodeling. Arg is expressed in the dorsal mesoderm at the onset of gastrulation, and both gain- and loss-of-function of Arg disrupted axial development in Xenopus embryos. Arg controlled migration of anterior mesendoderm, influenced cell decision on individual versus collective migration, and modulated spreading and protrusive activities of anterior mesendodermal cells. Arg also regulated convergent extension of the trunk mesoderm by influencing cell intercalation behaviors. Arg modulated actin organization to control dynamic F-actin distribution at the cell-cell contact or in membrane protrusions. The functions of Arg required an intact tyrosine kinase domain but not the actin-binding motifs in its carboxyl terminus. Arg acted downstream of receptor tyrosine kinases to regulate phosphorylation of endogenous CrkII and paxillin, adaptor proteins involved in activation of Rho family GTPases and actin reorganization. Our data demonstrate that Arg is a crucial cytoplasmic signaling molecule that controls dynamic actin remodeling and mesodermal cell behaviors during Xenopus gastrulation.
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Affiliation(s)
- Gustavo Bonacci
- Department of Cell Biology, University of Alabama at Birmingham, AL 35294, USA
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31
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Huang CW, Chen HY, Yen MH, Chen JJW, Young TH, Cheng JY. Gene expression of human lung cancer cell line CL1-5 in response to a direct current electric field. PLoS One 2011; 6:e25928. [PMID: 21998723 PMCID: PMC3187831 DOI: 10.1371/journal.pone.0025928] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2011] [Accepted: 09/13/2011] [Indexed: 12/21/2022] Open
Abstract
Background Electrotaxis is the movement of adherent living cells in response to a direct current (dc) electric field (EF) of physiological strength. Highly metastatic human lung cancer cells, CL1–5, exhibit directional migration and orientation under dcEFs. To understand the transcriptional response of CL1–5 cells to a dcEF, microarray analysis was performed in this study. Methodology/Principal Findings A large electric-field chip (LEFC) was designed, fabricated, and used in this study. CL1–5 cells were treated with the EF strength of 0mV/mm (the control group) and 300mV/mm (the EF-treated group) for two hours. Signaling pathways involving the genes that expressed differently between the two groups were revealed. It was shown that the EF-regulated genes highly correlated to adherens junction, telomerase RNA component gene regulation, and tight junction. Some up-regulated genes such as ACVR1B and CTTN, and some down-regulated genes such as PTEN, are known to be positively and negatively correlated to cell migration, respectively. The protein-protein interactions of adherens junction-associated EF-regulated genes suggested that platelet-derived growth factor (PDGF) receptors and ephrin receptors may participate in sensing extracellular electrical stimuli. We further observed a high percentage of significantly regulated genes which encode cell membrane proteins, suggesting that dcEF may directly influence the activity of cell membrane proteins in signal transduction. Conclusions/Significance In this study, some of the EF-regulated genes have been reported to be essential whereas others are novel for electrotaxis. Our result confirms that the regulation of gene expression is involved in the mechanism of electrotactic response.
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Affiliation(s)
- Ching-Wen Huang
- Institute of Biomedical Engineering, National Taiwan University, Taipei, Taiwan
- Research Center for Applied Sciences, Academia Sinica, Taipei, Taiwan
| | - Huai-Yi Chen
- Research Center for Applied Sciences, Academia Sinica, Taipei, Taiwan
- Department of Engineering and System Science, National Tsing-Hua University, Hsinchu, Taiwan
- Nano Science and Technology Program, Taiwan International Graduate Program (TIGP), Academia Sinica, Taipei, Taiwan
| | - Meng-Hua Yen
- Institute of Biomedical Engineering, National Taiwan University, Taipei, Taiwan
- Research Center for Applied Sciences, Academia Sinica, Taipei, Taiwan
| | - Jeremy J. W. Chen
- Institutes of Biomedical Sciences and Molecular Biology, National Chung-Hsing University, Taichung, Taiwan
| | - Tai-Horng Young
- Institute of Biomedical Engineering, National Taiwan University, Taipei, Taiwan
| | - Ji-Yen Cheng
- Research Center for Applied Sciences, Academia Sinica, Taipei, Taiwan
- Department of Mechanical and Mechantronic Engineering, National Taiwan Ocean University, Keelung, Taiwan
- Institute of Biophotonics, National Yang-Ming University, Taipei, Taiwan
- * E-mail:
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32
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Liu Y, Wang Z, Kwong SQ, Lui ELH, Friedman SL, Li FR, Lam RWC, Zhang GC, Zhang H, Ye T. Inhibition of PDGF, TGF-β, and Abl signaling and reduction of liver fibrosis by the small molecule Bcr-Abl tyrosine kinase antagonist Nilotinib. J Hepatol 2011; 55:612-625. [PMID: 21251937 DOI: 10.1016/j.jhep.2010.11.035] [Citation(s) in RCA: 136] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/15/2010] [Revised: 10/31/2010] [Accepted: 11/25/2010] [Indexed: 01/18/2023]
Abstract
BACKGROUND & AIMS Nilotinib is a novel tyrosine kinase inhibitor of Bcr-Abl and other kinases. In this study, we have examined its activity as an anti-fibrotic agent. METHODS The in vitro effect of Nilotinib on rat and human HSCs was assessed using proliferation assays and Western blotting. The in vivo antifibrotic efficacy of Nilotinib was assessed in mice with liver fibrosis induced by CCl(4) and bile duct ligation (BDL). RESULTS Nilotinib inhibited proliferation, migration, and actin filament formation, as well as the expression of α-SMA and collagen in activated HSCs. Nilotinib induced apoptosis of HSCs, which was correlated with reduced bcl-2 expression, increased p53 expression, cleavage of PARP, as well as increased expression of PPARγ and TRAIL-R. Nilotinib also induced cell cycle arrest, accompanied by increased expression of p27 and downregulation of cyclin D1. Interestingly, Nilotinib not only inhibited activation of PDGFR, but also TGFRII through Src. Nilotinib significantly inhibited PDGF and TGFβ-simulated phosphorylation of ERK and Akt. Furthermore, PDGF- and TGFβ-activated phosphorylated form(s) of Abl in human HSCs were inhibited by Nilotinib. In vivo, Nilotinib reduced collagen deposition and α-SMA expression in CCl(4) and BDL-induced fibrosis. These beneficial effects were associated with suppressed expression of procollagen-(I), TIMP-1, CD31, CD34, VEGF, and VEGFR. Nilotinib could induce HSC undergoing apoptosis in vivo, which was correlated with downregulation of bcl-2. We also observed reduced expression of phosphorylated ERK, Akt, and Abl in the Nilotinib-treated CCl(4) and BDL livers. In addition to its antifibrotic activity, the drug was hepatoprotective and reduced the elevations of ALT and AST after CCl(4) and BDL. CONCLUSIONS These studies uncover a novel role of Bcr-Abl activity in treatment of liver fibrosis through multiple mechanisms and indicate that Nilotinib represents a potentially effective antifibrotic agent.
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Affiliation(s)
- Yuqing Liu
- Department of Applied Biology & Chemical Technology, The Hong Kong Polytechnic University, Hong Kong, China; Laboratory of Chemical Genomics, School of Chemical Biology and Biotechnology, The Shenzhen Graduate School of Peking University, Shenzhen 518055, China.
| | - Zhuo Wang
- Department of Applied Biology & Chemical Technology, The Hong Kong Polytechnic University, Hong Kong, China
| | - Shu Qin Kwong
- Department of Applied Biology & Chemical Technology, The Hong Kong Polytechnic University, Hong Kong, China
| | - Eric Lik Hang Lui
- Department of Biochemistry, The University of Hong Kong, Hong Kong, China
| | - Scott L Friedman
- Division of Liver Diseases, Mount Sinai School of Medicine, New York, NY, USA
| | - Fu Rong Li
- Clinical Medical Research Center, The Second Clinic Medicine College, Shenzhen People's Hospital, Jinan University, Shenzhen 518020, China
| | - Reni Wing Chi Lam
- Department of Applied Biology & Chemical Technology, The Hong Kong Polytechnic University, Hong Kong, China
| | - Guo Chao Zhang
- Clinical Medical Research Center, The Second Clinic Medicine College, Shenzhen People's Hospital, Jinan University, Shenzhen 518020, China
| | - Hui Zhang
- Laboratory of Chemical Genomics, School of Chemical Biology and Biotechnology, The Shenzhen Graduate School of Peking University, Shenzhen 518055, China
| | - Tao Ye
- Department of Applied Biology & Chemical Technology, The Hong Kong Polytechnic University, Hong Kong, China; Laboratory of Chemical Genomics, School of Chemical Biology and Biotechnology, The Shenzhen Graduate School of Peking University, Shenzhen 518055, China.
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33
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Huang CW, Chen HY, Yen MH, Chen JJW, Young TH, Cheng JY. Gene expression of human lung cancer cell line CL1-5 in response to a direct current electric field. PLoS One 2011. [PMID: 21998723 DOI: 10.1371/journal.pone.0025928.g001] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/15/2023] Open
Abstract
BACKGROUND Electrotaxis is the movement of adherent living cells in response to a direct current (dc) electric field (EF) of physiological strength. Highly metastatic human lung cancer cells, CL1-5, exhibit directional migration and orientation under dcEFs. To understand the transcriptional response of CL1-5 cells to a dcEF, microarray analysis was performed in this study. METHODOLOGY/PRINCIPAL FINDINGS A large electric-field chip (LEFC) was designed, fabricated, and used in this study. CL1-5 cells were treated with the EF strength of 0 mV/mm (the control group) and 300 mV/mm (the EF-treated group) for two hours. Signaling pathways involving the genes that expressed differently between the two groups were revealed. It was shown that the EF-regulated genes highly correlated to adherens junction, telomerase RNA component gene regulation, and tight junction. Some up-regulated genes such as ACVR1B and CTTN, and some down-regulated genes such as PTEN, are known to be positively and negatively correlated to cell migration, respectively. The protein-protein interactions of adherens junction-associated EF-regulated genes suggested that platelet-derived growth factor (PDGF) receptors and ephrin receptors may participate in sensing extracellular electrical stimuli. We further observed a high percentage of significantly regulated genes which encode cell membrane proteins, suggesting that dcEF may directly influence the activity of cell membrane proteins in signal transduction. CONCLUSIONS/SIGNIFICANCE In this study, some of the EF-regulated genes have been reported to be essential whereas others are novel for electrotaxis. Our result confirms that the regulation of gene expression is involved in the mechanism of electrotactic response.
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Affiliation(s)
- Ching-Wen Huang
- Institute of Biomedical Engineering, National Taiwan University, Taipei, Taiwan
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34
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Smith-Pearson PS, Greuber EK, Yogalingam G, Pendergast AM. Abl kinases are required for invadopodia formation and chemokine-induced invasion. J Biol Chem 2010; 285:40201-11. [PMID: 20937825 DOI: 10.1074/jbc.m110.147330] [Citation(s) in RCA: 66] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
The Abl tyrosine kinases, Abl and Arg, play a role in the regulation of the actin cytoskeleton by modulating cell-cell adhesion and cell motility. Deregulation of both the actin cytoskeleton and Abl kinases have been implicated in cancers. Abl kinase activity is elevated in a number of metastatic cancers and these kinases are activated downstream of several oncogenic growth factor receptor signaling pathways. However, the role of Abl kinases in regulation of the actin cytoskeleton during tumor progression and invasion remains elusive. Here we identify the Abl kinases as essential regulators of invadopodia assembly and function. We show that Abl kinases are activated downstream of the chemokine receptor, CXCR4, and are required for cancer cell invasion and matrix degradation induced by SDF1α, serum growth factors, and activated Src kinase. Moreover, Abl kinases are readily detected at invadopodia assembly sites and their inhibition prevents the assembly of actin and cortactin into organized invadopodia structures. We show that active Abl kinases form complexes with membrane type-1 matrix metalloproteinase (MT1-MMP), a critical invadopodia component required for matrix degradation. Further, loss of Abl kinase signaling induces internalization of MT1-MMP from the cell surface, promotes its accumulation in the perinuclear compartment and inhibits MT1-MMP tyrosine phosphorylation. Our findings reveal that Abl kinase signaling plays a critical role in invadopodia formation and function, and have far-reaching implications for the treatment of metastatic carcinomas.
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Affiliation(s)
- Pameeka S Smith-Pearson
- Department of Pharmacology and Cancer Biology, Duke University Medical Center, Durham, North Carolina 27710, USA
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35
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Abstract
ABL-family proteins comprise one of the best conserved branches of the tyrosine kinases. Each ABL protein contains an SH3-SH2-TK (Src homology 3-Src homology 2-tyrosine kinase) domain cassette, which confers autoregulated kinase activity and is common among nonreceptor tyrosine kinases. This cassette is coupled to an actin-binding and -bundling domain, which makes ABL proteins capable of connecting phosphoregulation with actin-filament reorganization. Two vertebrate paralogs, ABL1 and ABL2, have evolved to perform specialized functions. ABL1 includes nuclear localization signals and a DNA binding domain through which it mediates DNA damage-repair functions, whereas ABL2 has additional binding capacity for actin and for microtubules to enhance its cytoskeletal remodeling functions. Several types of posttranslational modifications control ABL catalytic activity, subcellular localization, and stability, with consequences for both cytoplasmic and nuclear ABL functions. Binding partners provide additional regulation of ABL catalytic activity, substrate specificity, and downstream signaling. Information on ABL regulatory mechanisms is being mined to provide new therapeutic strategies against hematopoietic malignancies caused by BCR-ABL1 and related leukemogenic proteins.
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Affiliation(s)
- John Colicelli
- Department of Biological Chemistry, Molecular Biology Institute and Jonsson Comprehensive Cancer Center, David Geffen School of Medicine at UCLA, Los Angeles, CA 90095, USA.
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36
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Paniagua RT, Fiorentino DF, Chung L, Robinson WH. Tyrosine kinases in inflammatory dermatologic disease. J Am Acad Dermatol 2010; 65:389-403. [PMID: 20584561 DOI: 10.1016/j.jaad.2010.04.026] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2010] [Revised: 04/07/2010] [Accepted: 04/12/2010] [Indexed: 02/07/2023]
Abstract
Tyrosine kinases (TKs) are enzymes that catalyze the phosphorylation of tyrosine residues on protein substrates. They are key components of signaling pathways that drive an array of cellular responses including proliferation, differentiation, migration, and survival. Specific TKs have recently been identified as critical to the pathogenesis of several autoimmune and inflammatory diseases. Small-molecule inhibitors of TKs are emerging as a novel class of therapy that may provide benefit in certain patient subsets. In this review, we highlight TK signaling implicated in inflammatory dermatologic diseases, evaluate strategies aimed at inhibiting these aberrant signaling pathways, and discuss prospects for future drug development.
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Affiliation(s)
- Ricardo T Paniagua
- Division of Immunology and Rheumatology, Department of Medicine, Stanford University School of Medicine, Stanford, California; Geriatric Research Education and Clinical Center, Palo Alto Department of Veterans Affairs Health Care System, Palo Alto, California
| | - David F Fiorentino
- Department of Dermatology, Stanford University School of Medicine, Stanford, California
| | - Lorinda Chung
- Division of Immunology and Rheumatology, Department of Medicine, Stanford University School of Medicine, Stanford, California; Geriatric Research Education and Clinical Center, Palo Alto Department of Veterans Affairs Health Care System, Palo Alto, California
| | - William H Robinson
- Division of Immunology and Rheumatology, Department of Medicine, Stanford University School of Medicine, Stanford, California; Geriatric Research Education and Clinical Center, Palo Alto Department of Veterans Affairs Health Care System, Palo Alto, California.
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Miller MM, Lapetina S, MacGrath SM, Sfakianos MK, Pollard TD, Koleske AJ. Regulation of actin polymerization and adhesion-dependent cell edge protrusion by the Abl-related gene (Arg) tyrosine kinase and N-WASp. Biochemistry 2010; 49:2227-34. [PMID: 20146487 PMCID: PMC2836179 DOI: 10.1021/bi901721u] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Extracellular cues stimulate the Abl family nonreceptor tyrosine kinase Arg to promote actin-based cell edge protrusions. Several Arg-interacting proteins are potential links to the actin cytoskeleton, but exactly how Arg stimulates actin polymerization and cellular protrusion has not yet been fully elucidated. We used affinity purification to identify N-WASp as a novel binding partner of Arg. N-WASp activates the Arp2/3 complex and is an effector of Abl. We find that the Arg SH3 domain binds directly to N-WASp. Arg phosphorylates N-WASp on Y256, modestly increasing the affinity of Arg for N-WASp, an interaction that does not require the Arg SH2 domain. The Arg SH3 domain stimulates N-WASp-dependent actin polymerization in vitro, and Arg phosphorylation of N-WASp weakly stimulates this effect. Arg and N-WASp colocalize to adhesion-dependent cell edge protrusions in vivo. The cell edge protrusion defects of arg-/- fibroblasts can be complemented by re-expression of an Arg-yellow fluorescent protein (YFP) fusion, but not by an N-WASp binding-deficient Arg SH3 domain point mutant. These results suggest that Arg promotes actin-based protrusions in response to extracellular stimuli through phosphorylation of and physical interactions with N-WASp.
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Affiliation(s)
- Matthew M Miller
- Department of Cell Biology, Yale University, New Haven, Connecticut 06520, USA
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Bradley WD, Koleske AJ. Regulation of cell migration and morphogenesis by Abl-family kinases: emerging mechanisms and physiological contexts. J Cell Sci 2009; 122:3441-54. [PMID: 19759284 DOI: 10.1242/jcs.039859] [Citation(s) in RCA: 139] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
The Abl-family non-receptor tyrosine kinases are essential regulators of the cytoskeleton. They transduce diverse extracellular cues into cytoskeletal rearrangements that have dramatic effects on cell motility and morphogenesis. Recent biochemical and genetic studies have revealed several mechanisms that Abl-family kinases use to mediate these effects. Abl-family kinases stimulate actin polymerization through the activation of cortactin, hematopoietic lineage cell-specific protein (HS1), WASp- and WAVE-family proteins, and Rac1. They also attenuate cell contractility by inhibiting RhoA and altering adhesion dynamics. These pathways impinge on several physiological processes, including development and maintenance of the nervous and immune systems, and epithelial morphogenesis. Elucidating how Abl-family kinases are regulated, and where and when they coordinate cytoskeletal changes, is essential for garnering a better understanding of these complex processes.
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Affiliation(s)
- William D Bradley
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT 06520, USA.
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Chow KU, Nowak D, Trepohl B, Hochmuth S, Schneider B, Hoelzer D, Mitrou PS, Bergmann L, Ottmann OG, Boehrer S. The tyrosine kinase inhibitor AMN107 (Nilotinib) exhibits off-target effects in lymphoblastic cell lines. Leuk Lymphoma 2009; 48:1379-88. [PMID: 17613767 DOI: 10.1080/10428190701385181] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
The aminopyrimidine inhibitor AMN107 (Nilotinib) was rationally designed to antagonize the aberrant tyrosine kinase activity of Bcr-Abl-positive cells. We here evaluated, whether AMN107 is also able to induce apoptosis in Bcr-Abl-negative cells of lymphatic origin. The B-cell lines DOHH-2 and WSU-NHL and the T-cell lines Jurkat and HUT78 were incubated with increasing amounts of AMN107 corresponding to clinically achievable dosages. Subsequently, induced molecular changes were assessed by FACS analysis, Western blot, and enzyme activity assays. Although AMN107 exhibited only a minor apoptosis-inducing effect in the T-cell lines, it exerted a considerable, dose-dependent cytotoxicity in the B-cell lines. Using selective caspase-inhibitors, we show that apoptosis in responder cell lines critically relies on activation of caspase-6 and caspase-9. Cell lines sensitive and resistant towards AMN107 can be discriminated by their differential expression of Src-kinases. Although the AMN107-sensitive cell lines DOHH-2 and WSU-NHL exhibited low or no expression of the Src-kinases Lck, phosphorylated Lck, and Yes with a concomitant high expression of Hck, Lyn, and phosphorylated Lyn, the expression pattern of these kinases was inverse in the AMN107-resistant T-cell lines. In conclusion, this is the first report providing evidence that activity of AMN107 is not restricted to Bcr-Abl, c-Kit, or PDGFR-positive cells, but also extends to lymphatic cell lines of B-cell origin.
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Affiliation(s)
- Kai Uwe Chow
- Department of Medicine II, Hematology and Oncology, Johann Wolfgang Goethe-University Hospital. Frankfurt am Main, Germany
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Lapetina S, Mader CC, Machida K, Mayer BJ, Koleske AJ. Arg interacts with cortactin to promote adhesion-dependent cell edge protrusion. ACTA ACUST UNITED AC 2009; 185:503-19. [PMID: 19414610 PMCID: PMC2700396 DOI: 10.1083/jcb.200809085] [Citation(s) in RCA: 83] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
The molecular mechanisms by which the Abelson (Abl) or Abl-related gene (Arg) kinases interface with the actin polymerization machinery to promote cell edge protrusions during cell–matrix adhesion are unclear. In this study, we show that interactions between Arg and the Arp2/3 complex regulator cortactin are essential to mediate actin-based cell edge protrusion during fibroblast adhesion to fibronectin. Arg-deficient and cortactin knockdown fibroblasts exhibit similar defects in adhesion-dependent cell edge protrusion, which can be restored via reexpression of Arg and cortactin. Arg interacts with cortactin via both binding and catalytic events. The cortactin Src homology (SH) 3 domain binds to a Pro-rich motif in the Arg C terminus. Arg mediates adhesion-dependent phosphorylation of cortactin, creating an additional binding site for the Arg SH2 domain. Mutation of residues that mediate Arg–cortactin interactions abrogate the abilities of both proteins to support protrusions, and the Nck adapter, which binds phosphocortactin, is also required. These results demonstrate that interactions between Arg, cortactin, and Nck1 are critical to promote adhesion-dependent cell edge protrusions.
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Affiliation(s)
- Stefanie Lapetina
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT 06520, USA
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Abstract
Stimulation of the T-cell antigen receptor (TCR) leads to the activation of signaling pathways that are essential for T-cell development and the response of mature T cells to antigens. The TCR has no intrinsic catalytic activity, but TCR engagement results in tyrosine phosphorylation of downstream targets by non-receptor tyrosine kinases. Three families of tyrosine kinases have long been recognized to play critical roles in TCR-dependent signaling. They are the Src, zeta-associated protein of 70 kDa, and Tec families of kinases. More recently, the Abelson (Abl) tyrosine kinases have been shown to be activated by TCR engagement and to be required for maximal TCR signaling. Using T-cell conditional knockout mice deficient for Abl family kinases, Abl (Abl1) and Abl-related gene (Arg) (Abl2), it was recently shown that loss of Abl kinases results in defective T-cell development and a partial block in the transition to the CD4(+)CD8(+) stage. Abl/Arg double null T cells exhibit impaired TCR-induced signaling, proliferation, and cytokine production. Moreover, conditional knockout mice lacking Abl and Arg in T cells exhibit impaired CD8(+) T-cell expansion in vivo upon Listeria monocytogenes infection. Thus, Abl kinase signaling is required for both T-cell development and mature T-cell function.
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Affiliation(s)
- Jing Jin Gu
- Department of Pharmacology and Cancer Biology, Duke University Medical Center, Durham, NC 27710, USA
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Srinivasan D, Kaetzel DM, Plattner R. Reciprocal regulation of Abl and receptor tyrosine kinases. Cell Signal 2009; 21:1143-50. [PMID: 19275932 DOI: 10.1016/j.cellsig.2009.03.003] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2009] [Accepted: 03/02/2009] [Indexed: 01/27/2023]
Abstract
Previously, we showed that Abl kinases (c-Abl, Arg) are activated downstream of PDGF in a manner dependent on Src kinases and PLC-gamma1, and promote PDGF-mediated proliferation and migration of fibroblasts. We additionally demonstrated that Abl kinases bind directly to PDGFR-beta via their SH2 domains.In this study, we extend these findings by demonstrating that Abl kinases also are activated downstream of aPDGF autocrine growth loop in glioblastoma cells, indicating that the PDGFR-Abl signaling pathway also is likely to be important in glioblastoma development and/or progression.We recently showed that Abl kinases are highly active in many breast cancer cell lines, and the Her-2 receptor tyrosine kinase contributes to c-Abl and Arg kinase activation. In this study, we show that Abl kinase SH2 domains bind directly to Her-2, and like PDGFR-beta , Her-2 directly phosphorylates c-Abl. Previously, we demonstrated that PDGFR-beta directly phosphorylates Abl kinases in vitro, and Abl kinases reciprocally phosphorylate PDGFR-beta . Here, we show that PDGFR-beta-phosphorylation of Abl kinases has functional consequences as PDGFR-beta phosphorylates Abl kinases on Y245 and Y412, sites known to be required for activation of Abl kinases. Moreover, PDGFR-beta phosphorylates Arg on two additional unique sites whose function is unknown. Importantly, we also show that Abl-dependent phosphorylation of PDGFR-beta has functional and biological significances. c-Abl phosphorylates three tyrosine residues on PDGFR-beta (Y686, Y934, Y970), while Arg only phosphorylatesY686. Y686 and Y934 reside in PDGFR-beta catalytic domains, while Y970 is in the C-terminal tail. Using site-directed mutagenesis, we show that Abl-dependent phosphorylation of PDGFR-beta activates PDGFR-beta activity, in vitro, but serves to downregulate PDGFR-mediated chemotaxis. These data are exciting as they indicate that Abl kinases not only are activated by PDGFR and promote PDGFR-mediated proliferation and migration,but also act in an intricate negative feedback loop to turn-off PDGFR-mediated chemotaxis.
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Affiliation(s)
- Divyamani Srinivasan
- Department of Molecular and Biomedical Pharmacology, University of Kentucky School of Medicine, 800 Rose Street, Lexington, KY 40346, USA
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Beazely MA, Weerapura M, MacDonald JF. Abelson tyrosine kinase links PDGFbeta receptor activation to cytoskeletal regulation of NMDA receptors in CA1 hippocampal neurons. Mol Brain 2008; 1:20. [PMID: 19077273 PMCID: PMC2651131 DOI: 10.1186/1756-6606-1-20] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2008] [Accepted: 12/12/2008] [Indexed: 01/12/2023] Open
Abstract
Background We have previously demonstrated that PDGF receptor activation indirectly inhibits N-methyl-D-aspartate (NMDA) currents by modifying the cytoskeleton. PDGF receptor ligand is also neuroprotective in hippocampal slices and cultured neurons. PDGF receptors are tyrosine kinases that control a variety of signal transduction pathways including those mediated by PLCγ. In fibroblasts Src and another non-receptor tyrosine kinase, Abelson kinase (Abl), control PDGF receptor regulation of cytoskeletal dynamics. The mechanism whereby PDGF receptor regulates cytoskeletal dynamics in central neurons remains poorly understood. Results Intracellular applications of active Abl, but not heat-inactivated Abl, decreased NMDA-evoked currents in isolated hippocampal neurons. This mimics the effects of PDGF receptor activation in these neurons. The Abl kinase inhibitor, STI571, blocked the inhibition of NMDA currents by Abl. We demonstrate that PDGF receptors can activate Abl kinase in hippocampal neurons via mechanisms similar to those observed previously in fibroblasts. Furthermore, PDGFβ receptor activation alters the subcellular localization of Abl. Abl kinase is linked to actin cytoskeletal dynamics in many systems. We show that the inhibition of NMDA receptor currents by Abl kinase is blocked by the inclusion of the Rho kinase inhibitor, Y-27632, and that activation of Abl correlates with an increase in ROCK tyrosine phosphorylation. Conclusion This study demonstrates that PDGFβ receptors act via an interaction with Abl kinase and Rho kinase to regulated cytoskeletal regulation of NMDA receptor channels in CA1 pyramidal neurons.
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Abstract
c-Abl is a non-receptor tyrosine kinase which is localized both in the nucleus and cytoplasm, and is involved in the regulation of cell growth, survival and morphogenesis. Although c-Abl nuclear function has been extensively studied, recent data also indicate an important role in cytoplasmic signalling through mitogenic and adhesive receptors. Here, we review the mechanisms by which growth factors promote cytoplasmic c-Abl activation and signalling and its function in the induction of DNA synthesis, changes in cell morphology and receptor endocytosis. The importance of de-regulated c-Abl cytoplasmic signalling in solid tumours is also discussed.
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Mitra S, Beach C, Feng GS, Plattner R. SHP-2 is a novel target of Abl kinases during cell proliferation. J Cell Sci 2008; 121:3335-46. [PMID: 18827006 DOI: 10.1242/jcs.035691] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Abstract
Previously, we showed that Abl family tyrosine kinases are activated by growth factors, and Abl is required for transition from G1 to S phase during PDGF-mediated proliferation. Here, we show that the SHP-2 tyrosine phosphatase, which acts to promote proliferation in response to cytokines and growth factors, is a novel substrate of endogenous Abl kinases during growth factor-mediated cellular proliferation. Using a pharmacological inhibitor and RNAi, we show that endogenous Abl kinases phosphorylate SHP-2 on Y580, and induce sustained activation of ERK kinases in response to growth factor stimulation in fibroblasts. Consistent with these data, SHP-2 is required for Abl-dependent PDGF-mediated proliferation since expression of an activated form of SHP-2 rescues the ability of Abl-Arg null fibroblasts to transit from G1 to S phase, whereas inhibition of SHP-2 signaling reduces the ability of Abl kinases to rescue the proliferation defect. Abl kinases also indirectly mediate phosphorylation of SHP-2 on Y63 and Y279, which are frequent sites of germline mutation in two cancer susceptibility syndromes. Significantly, we demonstrate that phosphorylation of SHP-2 on Y279 downregulates growth factor-induced sustained ERK activation and proliferation, supporting a role for Abl kinases not only in potentiating growth factor-mediated SHP-2 signaling, but also in negative-feedback regulation.
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Affiliation(s)
- Sayan Mitra
- Department of Molecular and Biomedical Pharmacology, University of Kentucky, Lexington, KY 40536, USA
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Elwell CA, Ceesay A, Kim JH, Kalman D, Engel JN. RNA interference screen identifies Abl kinase and PDGFR signaling in Chlamydia trachomatis entry. PLoS Pathog 2008; 4:e1000021. [PMID: 18369471 PMCID: PMC2267011 DOI: 10.1371/journal.ppat.1000021] [Citation(s) in RCA: 123] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2007] [Accepted: 02/01/2008] [Indexed: 11/19/2022] Open
Abstract
To elucidate the mechanisms involved in early events in Chlamydia trachomatis infection, we conducted a large scale unbiased RNA interference screen in Drosophila melanogaster S2 cells. This allowed identification of candidate host factors in a simple non-redundant, genetically tractable system. From a library of 7,216 double stranded RNAs (dsRNA), we identified ∼226 host genes, including two tyrosine kinases, Abelson (Abl) kinase and PDGF- and VEGF-receptor related (Pvr), a homolog of the Platelet-derived growth factor receptor (PDGFR). We further examined the role of these two kinases in C. trachomatis binding and internalization into mammalian cells. Both kinases are phosphorylated upon infection and recruited to the site of bacterial attachment, but their roles in the infectious process are distinct. We provide evidence that PDGFRβ may function as a receptor, as inhibition of PDGFRβ by RNA interference or by PDGFRβ neutralizing antibodies significantly reduces bacterial binding, whereas depletion of Abl kinase has no effect on binding. Bacterial internalization can occur through activation of PDGFRβ or through independent activation of Abl kinase, culminating in phosphorylation of the Rac guanine nucleotide exchange factor (GEF), Vav2, and two actin nucleators, WAVE2 and Cortactin. Finally, we show that TARP, a bacterial type III secreted actin nucleator implicated in entry, is a target of Abl kinase. Together, our results demonstrate that PDGFRβ and Abl kinases function redundantly to promote efficient uptake of this obligate intracellular parasite. Chlamydia trachomatis infections are a worldwide problem; they are the leading cause of preventable blindness in developing nations and the most common cause of sexually transmitted disease in the Western world. Binding and entry into host cells are critical steps to the pathogenesis of this obligate intracellular parasite; however little is known regarding the mechanism of these processes. In this work, we describe a large scale RNA interference screen to identify host factors essential for early steps in C. trachomatis infection. We discover that the Platelet Derived Growth Factor Receptor β (PDGFRβ) can function as a receptor for C. trachomatis, and that activation of both PDGFRβ and Abl kinase signaling pathways by C. trachomatis leads to phosphorylation of a Rac guanine nucleotide exchange factor, Vav2, and several actin nucleators, including WAVE2, Cortactin, and TARP, a Chlamydia type III secreted effector. Our work suggests a model of redundant activation of PDGFRβ and Abl kinase upon C. trachomatis binding that culminates in cytoskeletal rearrangements that modulate efficient uptake of this obligate intracellular parasite.
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Affiliation(s)
- Cherilyn A. Elwell
- Department of Medicine, University of California San Francisco, San Francisco, California, United States of America
| | - Alhaji Ceesay
- Department of Medicine, University of California San Francisco, San Francisco, California, United States of America
| | - Jung Hwa Kim
- Department of Medicine, University of California San Francisco, San Francisco, California, United States of America
| | - Daniel Kalman
- Department of Pathology and Laboratory of Medicine, Emory University, Atlanta, Georgia, United States of America
| | - Joanne N. Engel
- Department of Medicine, University of California San Francisco, San Francisco, California, United States of America
- Department of Microbiology and Immunology, University of California San Francisco, San Francisco, California, United States of America
- * E-mail:
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Abstract
Imatinib inhibits tyrosine kinases important in osteoclast (c-Fms) and osteoblast (platelet-derived growth factor receptor [PDGF-R], c-Abl) function, suggesting that long-term therapy may alter bone homeostasis. To investigate this question, we measured the trabecular bone volume (TBV) in iliac crest bone biopsies taken from chronic myeloid leukemia (CML) patients at diagnosis and again after 2 to 4 years of imatinib therapy. Half the patients (8 of 17) showed a substantive increase in TBV (> 2-fold), after imatinib therapy, with the TBV in the posttreatment biopsy typically surpassing the normal upper limit for the patient's age group. Imatinib-treated patients exhibited reduced serum calcium and phosphate levels with hypophosphatemia evident in 53% (9 of 17) of patients. In vitro, imatinib suppressed osteoblast proliferation and stimulated osteogenic gene expression and mineralized-matrix production by inhibiting PDGF receptor function. In PDGF-stimulated cultures, imatinib dose-dependently inhibited activation of Akt and Crk-L. Using pharmacologic inhibitors, inhibition of PI3-kinase/Akt activation promoted mineral formation, suggesting a possible molecular mechanism for the imatinib-mediated increase in TBV in vivo. Further investigation is required to determine whether the increase in TBV associated with imatinib therapy may represent a novel therapeutic avenue for the treatment of diseases that are characterized by generalized bone loss.
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Abl tyrosine kinases regulate cell-cell adhesion through Rho GTPases. Proc Natl Acad Sci U S A 2007; 104:17686-91. [PMID: 17965237 DOI: 10.1073/pnas.0703077104] [Citation(s) in RCA: 102] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Adherens junctions are calcium-dependent cell-cell contacts that link neighboring cells through cadherin receptors. Coordinated regulation of the actin cytoskeleton by the Rho GTPases is required for the formation and dissolution of adherens junctions. However, the pathways that link cadherin signaling to cytoskeletal regulation remain poorly defined. Here we identify the Abl family kinases as critical mediators of cadherin-mediated adhesion. Endogenous Abl family kinases, Abl and Arg, are activated and required for Rac activation after cadherin engagement and regulate the formation and maintenance of adherens junctions in mammalian cells. Significantly, we show that Abl-dependent regulation of the Rho-ROCK-myosin signaling pathway is critical for the maintenance of adherens junctions. Inhibition of the Abl kinases in epithelial sheets results in the activation of Rho and its downstream target ROCK, leading to enhanced phosphorylation of the myosin regulatory light chain. These signaling events result in enhanced stress fiber formation and increased actomyosin contractility, thereby disrupting adherens junctions. Conversely, Arg gain of function promotes adherens junction formation through a Crk-dependent pathway in cells with weak junctions. These data identify the Abl kinases as a regulatory link between the cadherin-catenin adhesion complex and the actin cytoskeleton through regulation of Rac and Rho during adherens junction formation, and also reveal a functional link between Abl and Rho that is essential for adherens junction stability.
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Stevens TL, Rogers EM, Koontz LM, Fox DT, Homem CCF, Nowotarski SH, Artabazon NB, Peifer M. Using Bcr-Abl to examine mechanisms by which abl kinase regulates morphogenesis in Drosophila. Mol Biol Cell 2007; 19:378-93. [PMID: 17959833 DOI: 10.1091/mbc.e07-01-0008] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
Abstract
Signaling by the nonreceptor tyrosine kinase Abelson (Abl) plays key roles in normal development, whereas its inappropriate activation helps trigger the development of several forms of leukemia. Abl is best known for its roles in axon guidance, but Abl and its relatives also help regulate embryonic morphogenesis in epithelial tissues. Here, we explore the role of regulation of Abl kinase activity during development. We first compare the subcellular localization of Abl protein and of active Abl, by using a phosphospecific antibody, providing a catalog of places where Abl is activated. Next, we explore the consequences for morphogenesis of overexpressing wild-type Abl or expressing the activated form found in leukemia, Bcr-Abl. We find dose-dependent effects of elevating Abl activity on morphogenetic movements such as head involution and dorsal closure, on cell shape changes, on cell protrusive behavior, and on the organization of the actin cytoskeleton. Most of the effects of Abl activation parallel those caused by reduction in function of its target Enabled. Abl activation leads to changes in Enabled phosphorylation and localization, suggesting a mechanism of action. These data provide new insight into how regulated Abl activity helps direct normal development and into possible biological functions of Bcr-Abl.
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Affiliation(s)
- Traci L Stevens
- Department of Biology and Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599-3280, USA
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50
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Peacock JG, Miller AL, Bradley WD, Rodriguez OC, Webb DJ, Koleske AJ. The Abl-related gene tyrosine kinase acts through p190RhoGAP to inhibit actomyosin contractility and regulate focal adhesion dynamics upon adhesion to fibronectin. Mol Biol Cell 2007; 18:3860-72. [PMID: 17652459 PMCID: PMC1995720 DOI: 10.1091/mbc.e07-01-0075] [Citation(s) in RCA: 67] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023] Open
Abstract
In migrating cells, actin polymerization promotes protrusion of the leading edge, whereas actomyosin contractility powers net cell body translocation. Although they promote F-actin-dependent protrusions of the cell periphery upon adhesion to fibronectin (FN), Abl family kinases inhibit cell migration on FN. We provide evidence here that the Abl-related gene (Arg/Abl2) kinase inhibits fibroblast migration by attenuating actomyosin contractility and regulating focal adhesion dynamics. arg-/- fibroblasts migrate at faster average speeds than wild-type (wt) cells, whereas Arg re-expression in these cells slows migration. Surprisingly, the faster migrating arg-/- fibroblasts have more prominent F-actin stress fibers and focal adhesions and exhibit increased actomyosin contractility relative to wt cells. Interestingly, Arg requires distinct functional domains to inhibit focal adhesions and actomyosin contractility. The kinase domain-containing Arg N-terminal half can act through the RhoA inhibitor p190RhoGAP to attenuate stress fiber formation and cell contractility. However, Arg requires both its kinase activity and its cytoskeleton-binding C-terminal half to fully inhibit focal adhesions. Although focal adhesions do not turn over efficiently in the trailing edge of arg-/- cells, the increased contractility of arg-/- cells tears the adhesions from the substrate, allowing for the faster migration observed in these cells. Together, our data strongly suggest that Arg inhibits cell migration by restricting actomyosin contractility and regulating its coupling to the substrate through focal adhesions.
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Affiliation(s)
| | - Ann L. Miller
- *Department of Molecular Biophysics and Biochemistry
| | | | - Olga C. Rodriguez
- Department of Cell Biology, The Scripps Research Institute, La Jolla, CA 92037; and
| | - Donna J. Webb
- Department of Biological Sciences, Vanderbilt University, Nashville, TN 37235
| | - Anthony J. Koleske
- *Department of Molecular Biophysics and Biochemistry
- Department of Neurobiology, and
- Interdepartmental Neuroscience Program, Yale University, New Haven, CT 06511
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