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Pergu R, Shoba VM, Chaudhary SK, Munkanatta Godage DNP, Deb A, Singha S, Dhawa U, Singh P, Anokhina V, Singh S, Siriwardena SU, Choudhary A. Development and Applications of Chimera Platforms for Tyrosine Phosphorylation. ACS CENTRAL SCIENCE 2023; 9:1558-1566. [PMID: 37637727 PMCID: PMC10450875 DOI: 10.1021/acscentsci.3c00200] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/14/2023] [Indexed: 08/29/2023]
Abstract
Chimeric small molecules that induce post-translational modification (PTM) on a target protein by bringing it into proximity to a PTM-inducing enzyme are furnishing novel modalities to perturb protein function. Despite recent advances, such molecules are unavailable for a critical PTM, tyrosine phosphorylation. Furthermore, the contemporary design paradigm of chimeric molecules, formed by joining a noninhibitory binder of the PTM-inducing enzyme with the binder of the target protein, prohibits the recruitment of most PTM-inducing enzymes as their noninhibitory binders are unavailable. Here, we report two platforms to generate phosphorylation-inducing chimeric small molecules (PHICS) for tyrosine phosphorylation. We generate PHICS from both noninhibitory binders (scantily available, platform 1) and kinase inhibitors (abundantly available, platform 2) using cysteine-based group transfer chemistry. PHICS triggered phosphorylation on tyrosine residues in diverse sequence contexts and target proteins (e.g., membrane-associated, cytosolic) and displayed multiple bioactivities, including the initiation of a growth receptor signaling cascade and the death of drug-resistant cancer cells. These studies provide an approach to induce biologically relevant PTM and lay the foundation for pharmacologic PTM editing (i.e., induction or removal) of target proteins using abundantly available inhibitors of PTM-inducing or -erasing enzymes.
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Affiliation(s)
- Rajaiah Pergu
- Chemical
Biology and Therapeutics Science, Broad
Institute of MIT and Harvard, Cambridge, Massachusetts 02142, United States
| | - Veronika M. Shoba
- Chemical
Biology and Therapeutics Science, Broad
Institute of MIT and Harvard, Cambridge, Massachusetts 02142, United States
| | - Santosh K. Chaudhary
- Chemical
Biology and Therapeutics Science, Broad
Institute of MIT and Harvard, Cambridge, Massachusetts 02142, United States
| | | | - Arghya Deb
- Chemical
Biology and Therapeutics Science, Broad
Institute of MIT and Harvard, Cambridge, Massachusetts 02142, United States
| | - Santanu Singha
- Chemical
Biology and Therapeutics Science, Broad
Institute of MIT and Harvard, Cambridge, Massachusetts 02142, United States
| | - Uttam Dhawa
- Chemical
Biology and Therapeutics Science, Broad
Institute of MIT and Harvard, Cambridge, Massachusetts 02142, United States
| | - Prashant Singh
- Chemical
Biology and Therapeutics Science, Broad
Institute of MIT and Harvard, Cambridge, Massachusetts 02142, United States
| | - Viktoriya Anokhina
- Chemical
Biology and Therapeutics Science, Broad
Institute of MIT and Harvard, Cambridge, Massachusetts 02142, United States
| | - Sameek Singh
- Chemical
Biology and Therapeutics Science, Broad
Institute of MIT and Harvard, Cambridge, Massachusetts 02142, United States
| | - Sachini U. Siriwardena
- Chemical
Biology and Therapeutics Science, Broad
Institute of MIT and Harvard, Cambridge, Massachusetts 02142, United States
| | - Amit Choudhary
- Chemical
Biology and Therapeutics Science, Broad
Institute of MIT and Harvard, Cambridge, Massachusetts 02142, United States
- Department
of Medicine, Harvard Medical School, Boston, Massachusetts 02115, United States
- Divisions
of Renal Medicine and Engineering, Brigham
and Women’s Hospital, Boston, Massachusetts 02115, United States
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2
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Gerritsen JS, Faraguna JS, Bonavia R, Furnari FB, White FM. Predictive data-driven modeling of C-terminal tyrosine function in the EGFR signaling network. Life Sci Alliance 2023; 6:e202201466. [PMID: 37169593 PMCID: PMC10176108 DOI: 10.26508/lsa.202201466] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2022] [Revised: 04/30/2023] [Accepted: 05/01/2023] [Indexed: 05/13/2023] Open
Abstract
The epidermal growth factor receptor (EGFR) has been studied extensively because of its critical role in cellular signaling and association with disease. Previous models have elucidated interactions between EGFR and downstream adaptor proteins or showed phenotypes affected by EGFR. However, the link between specific EGFR phosphorylation sites and phenotypic outcomes is still poorly understood. Here, we employed a suite of isogenic cell lines expressing site-specific mutations at each of the EGFR C-terminal phosphorylation sites to interrogate their role in the signaling network and cell biological response to stimulation. Our results demonstrate the resilience of the EGFR network, which was largely similar even in the context of multiple Y-to-F mutations in the EGFR C-terminal tail, while also revealing nodes in the network that have not previously been linked to EGFR signaling. Our data-driven model highlights the signaling network nodes associated with distinct EGF-driven cell responses, including migration, proliferation, and receptor trafficking. Application of this same approach to less-studied RTKs should provide a plethora of novel associations that should lead to an improved understanding of these signaling networks.
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Affiliation(s)
- Jacqueline S Gerritsen
- Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA, USA
- Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, MA, USA
- Center for Precision Cancer Medicine, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Joseph S Faraguna
- Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Rudy Bonavia
- Ludwig Institute for Cancer Research, La Jolla, CA, USA
| | - Frank B Furnari
- Ludwig Institute for Cancer Research, La Jolla, CA, USA
- Moores Cancer Center, University of California at San Diego, La Jolla, CA, USA
- Department of Medicine, University of California at San Diego, La Jolla, CA, USA
| | - Forest M White
- Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA, USA
- Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, MA, USA
- Center for Precision Cancer Medicine, Massachusetts Institute of Technology, Cambridge, MA, USA
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3
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Sun Z, Li Y, Tan X, Liu W, He X, Pan D, Li E, Xu L, Long L. Friend or Foe: Regulation, Downstream Effectors of RRAD in Cancer. Biomolecules 2023; 13:biom13030477. [PMID: 36979412 PMCID: PMC10046484 DOI: 10.3390/biom13030477] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2023] [Revised: 02/28/2023] [Accepted: 03/01/2023] [Indexed: 03/08/2023] Open
Abstract
Ras-related associated with diabetes (RRAD), a member of the Ras-related GTPase superfamily, is primarily a cytosolic protein that actives in the plasma membrane. RRAD is highly expressed in type 2 diabetes patients and as a biomarker of congestive heart failure. Mounting evidence showed that RRAD is important for the progression and metastasis of tumor cells, which play opposite roles as an oncogene or tumor suppressor gene depending on cancer and cell type. These findings are of great significance, especially given that relevant molecular mechanisms are being discovered. Being regulated in various pathways, RRAD plays wide spectrum cellular activity including tumor cell division, motility, apoptosis, and energy metabolism by modulating tumor-related gene expression and interacting with multiple downstream effectors. Additionally, RRAD in senescence may contribute to its role in cancer. Despite the twofold characters of RRAD, targeted therapies are becoming a potential therapeutic strategy to combat cancers. This review will discuss the dual identity of RRAD in specific cancer type, provides an overview of the regulation and downstream effectors of RRAD to offer valuable insights for readers, explore the intracellular role of RRAD in cancer, and give a reference for future mechanistic studies.
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Affiliation(s)
- Zhangyue Sun
- Department of Biochemistry and Molecular Biology, Shantou University Medical College, Shantou 515041, China
- Cancer Research Center, Institute of Basic Medical Science, Shantou University Medical College, Shantou 515041, China
| | - Yongkang Li
- Department of Biochemistry and Molecular Biology, Shantou University Medical College, Shantou 515041, China
- Cancer Research Center, Institute of Basic Medical Science, Shantou University Medical College, Shantou 515041, China
| | - Xiaolu Tan
- Department of Biochemistry and Molecular Biology, Shantou University Medical College, Shantou 515041, China
- Cancer Research Center, Institute of Basic Medical Science, Shantou University Medical College, Shantou 515041, China
| | - Wanyi Liu
- Department of Biochemistry and Molecular Biology, Shantou University Medical College, Shantou 515041, China
- Cancer Research Center, Institute of Basic Medical Science, Shantou University Medical College, Shantou 515041, China
| | - Xinglin He
- Department of Biochemistry and Molecular Biology, Shantou University Medical College, Shantou 515041, China
- Cancer Research Center, Institute of Basic Medical Science, Shantou University Medical College, Shantou 515041, China
| | - Deyuan Pan
- Department of Biochemistry and Molecular Biology, Shantou University Medical College, Shantou 515041, China
- Cancer Research Center, Institute of Basic Medical Science, Shantou University Medical College, Shantou 515041, China
- Guangdong Provincial Key Laboratory of Infectious Diseases and Molecular Immunopathology, Shantou University Medical College, Shantou 515041, China
- The Key Laboratory of Molecular Biology for High Cancer Incidence Coastal Chaoshan Area, Shantou University Medical College, Shantou 515041, China
- Institute of Oncologic Pathology, Shantou University Medical College, Shantou 515041, China
| | - Enmin Li
- Department of Biochemistry and Molecular Biology, Shantou University Medical College, Shantou 515041, China
- Cancer Research Center, Institute of Basic Medical Science, Shantou University Medical College, Shantou 515041, China
- Guangdong Provincial Key Laboratory of Infectious Diseases and Molecular Immunopathology, Shantou University Medical College, Shantou 515041, China
- The Key Laboratory of Molecular Biology for High Cancer Incidence Coastal Chaoshan Area, Shantou University Medical College, Shantou 515041, China
- Institute of Oncologic Pathology, Shantou University Medical College, Shantou 515041, China
| | - Liyan Xu
- Department of Biochemistry and Molecular Biology, Shantou University Medical College, Shantou 515041, China
- Cancer Research Center, Institute of Basic Medical Science, Shantou University Medical College, Shantou 515041, China
- Guangdong Provincial Key Laboratory of Infectious Diseases and Molecular Immunopathology, Shantou University Medical College, Shantou 515041, China
- The Key Laboratory of Molecular Biology for High Cancer Incidence Coastal Chaoshan Area, Shantou University Medical College, Shantou 515041, China
- Institute of Oncologic Pathology, Shantou University Medical College, Shantou 515041, China
| | - Lin Long
- Department of Biochemistry and Molecular Biology, Shantou University Medical College, Shantou 515041, China
- Cancer Research Center, Institute of Basic Medical Science, Shantou University Medical College, Shantou 515041, China
- Guangdong Provincial Key Laboratory of Infectious Diseases and Molecular Immunopathology, Shantou University Medical College, Shantou 515041, China
- The Key Laboratory of Molecular Biology for High Cancer Incidence Coastal Chaoshan Area, Shantou University Medical College, Shantou 515041, China
- Institute of Oncologic Pathology, Shantou University Medical College, Shantou 515041, China
- Correspondence: ; Tel.: +86-754-88900460; Fax: +86-754-88900847
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4
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Paris A, Tardif N, Baietti FM, Berra C, Leclair HM, Leucci E, Galibert M, Corre S. The AhR-SRC axis as a therapeutic vulnerability in BRAFi-resistant melanoma. EMBO Mol Med 2022; 14:e15677. [PMID: 36305167 PMCID: PMC9728058 DOI: 10.15252/emmm.202215677] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2022] [Revised: 09/30/2022] [Accepted: 09/30/2022] [Indexed: 12/14/2022] Open
Abstract
The nongenetic mechanisms required to control tumor phenotypic plasticity and shape drug-resistance remain unclear. We show here that the Aryl hydrocarbon Receptor (AhR) transcription factor directly regulates the gene expression program associated with the acquisition of resistance to BRAF inhibitor (BRAFi) in melanoma. In addition, we show in melanoma cells that canonical activation of AhR mediates the activation of the SRC pathway and promotes the acquisition of an invasive and aggressive resistant phenotype to front-line BRAFi treatment in melanoma. This nongenetic reprogramming identifies a clinically compatible approach to reverse BRAFi resistance in melanoma. Using a preclinical BRAFi-resistant PDX melanoma model, we demonstrate that SRC inhibition with dasatinib significantly re-sensitizes melanoma cells to BRAFi. Together we identify the AhR/SRC axis as a new therapeutic vulnerability to trigger resistance and warrant the introduction of SRC inhibitors during the course of the treatment in combination with front-line therapeutics to delay BRAFi resistance.
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Affiliation(s)
- Anaïs Paris
- Univ Rennes, CNRS, INSERM, IGDR (Institut de Génétique et Développement de Rennes) – UMR6290, ERL U1305RennesFrance
| | - Nina Tardif
- Univ Rennes, CNRS, INSERM, IGDR (Institut de Génétique et Développement de Rennes) – UMR6290, ERL U1305RennesFrance
| | - Francesca M Baietti
- Laboratory for RNA Cancer Biology, Department of OncologyLKI, KU LeuvenLeuvenBelgium,Trace PDX Platform, Department of OncologyLKI, KU LeuvenLeuvenBelgium
| | - Cyrille Berra
- Univ Rennes, CNRS, INSERM, IGDR (Institut de Génétique et Développement de Rennes) – UMR6290, ERL U1305RennesFrance,Department of Molecular Genetics and GenomicsHospital University of Rennes (CHU Rennes)RennesFrance
| | - Héloïse M Leclair
- Univ Rennes, CNRS, INSERM, IGDR (Institut de Génétique et Développement de Rennes) – UMR6290, ERL U1305RennesFrance
| | - Eleonora Leucci
- Laboratory for RNA Cancer Biology, Department of OncologyLKI, KU LeuvenLeuvenBelgium,Trace PDX Platform, Department of OncologyLKI, KU LeuvenLeuvenBelgium
| | - Marie‐Dominique Galibert
- Univ Rennes, CNRS, INSERM, IGDR (Institut de Génétique et Développement de Rennes) – UMR6290, ERL U1305RennesFrance,Department of Molecular Genetics and GenomicsHospital University of Rennes (CHU Rennes)RennesFrance
| | - Sébastien Corre
- Univ Rennes, CNRS, INSERM, IGDR (Institut de Génétique et Développement de Rennes) – UMR6290, ERL U1305RennesFrance
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5
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Nikou SA, Zhou C, Griffiths JS, Kotowicz NK, Coleman BM, Green MJ, Moyes DL, Gaffen SL, Naglik JR, Parker PJ. The Candida albicans toxin candidalysin mediates distinct epithelial inflammatory responses through p38 and EGFR-ERK pathways. Sci Signal 2022; 15:eabj6915. [PMID: 35380879 PMCID: PMC7612652 DOI: 10.1126/scisignal.abj6915] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
The fungal pathogen Candida albicans secretes the peptide toxin candidalysin, which damages epithelial cells and drives an innate inflammatory response mediated by the epidermal growth factor receptor (EGFR) and mitogen-activated protein kinase (MAPK) pathways and the transcription factor c-Fos. In cultured oral epithelial cells (OECs), candidalysin activated the p38 MAPK signaling pathway, which resulted in heat shock protein 27 (Hsp27) activation, IL-6 release, and EGFR phosphorylation without influencing the induction of c-Fos. p38 activation was not triggered by EGFR but by two non-redundant pathways involving MAPK kinases (MKKs) and the kinase Src, which differentially controlled p38 signaling outputs. Whereas MKKs mainly promoted p38-dependent release of IL-6, Src promoted p38-mediated phosphorylation of EGFR in a ligand-independent fashion. In parallel, candidalysin also activated the EGFR-ERK pathway in a manner that depended on EGFR ligands, resulting in c-Fos activation and release of the neutrophil-activating chemokines G-CSF and GM-CSF. In mice, p38 was important for the early clearance events of oral C. albicans infection, but c-Fos was not. These findings delineate how candidalysin activates the p38 and ERK MAPK pathways that differentially contribute to immune activation during C. albicans infection.
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Affiliation(s)
- Spyridoula-Angeliki Nikou
- Protein Phosphorylation Laboratory, Francis Crick Institute, London, UK.,Centre for Host-Microbiome Interactions, Faculty of Dentistry, Oral and Craniofacial Sciences, King's College London, London, UK
| | - Chunsheng Zhou
- Division of Rheumatology and Clinical Immunology, University of Pittsburgh, Pittsburgh, PA, USA
| | - James S Griffiths
- Centre for Host-Microbiome Interactions, Faculty of Dentistry, Oral and Craniofacial Sciences, King's College London, London, UK
| | - Natalia K Kotowicz
- Centre for Host-Microbiome Interactions, Faculty of Dentistry, Oral and Craniofacial Sciences, King's College London, London, UK
| | - Bianca M Coleman
- Division of Rheumatology and Clinical Immunology, University of Pittsburgh, Pittsburgh, PA, USA
| | - Mary J Green
- Experimental Histopathology Laboratory, Francis Crick Institute, London, UK
| | - David L Moyes
- Centre for Host-Microbiome Interactions, Faculty of Dentistry, Oral and Craniofacial Sciences, King's College London, London, UK
| | - Sarah L Gaffen
- Division of Rheumatology and Clinical Immunology, University of Pittsburgh, Pittsburgh, PA, USA
| | - Julian R Naglik
- Centre for Host-Microbiome Interactions, Faculty of Dentistry, Oral and Craniofacial Sciences, King's College London, London, UK
| | - Peter J Parker
- Protein Phosphorylation Laboratory, Francis Crick Institute, London, UK.,School of Cancer and Pharmaceutical Sciences, New Hunt's House, King's College London, London, UK
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6
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Rao TC, Ma VPY, Blanchard A, Urner TM, Grandhi S, Salaita K, Mattheyses AL. EGFR activation attenuates the mechanical threshold for integrin tension and focal adhesion formation. J Cell Sci 2020; 133:jcs238840. [PMID: 32546532 PMCID: PMC7358133 DOI: 10.1242/jcs.238840] [Citation(s) in RCA: 32] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2019] [Accepted: 06/04/2020] [Indexed: 02/06/2023] Open
Abstract
Mechanical forces, growth factors and the extracellular matrix all play crucial roles in cell adhesion. To understand how epidermal growth factor receptor (EGFR) impacts the mechanics of adhesion, we employed tension gauge tether (TGT) probes displaying the integrin ligand cRGDfK and quantified integrin tension. EGF exposure significantly increased spread area, cell circularity, integrated integrin tension, mechanical rupture density, radial organization and size of focal adhesions in Cos-7 cells on TGT surfaces. These findings suggest that EGFR regulates integrin tension and the spatial organization of focal adhesions. Additionally, we found that the mechanical tension threshold for outside-in integrin activation is tunable by EGFR. Parallel genetic and pharmacologic strategies demonstrated that these phenotypes are driven by ligand-dependent EGFR signaling. Our results establish a novel mechanism whereby EGFR regulates integrin activation and cell adhesion, providing control over cellular responses to the environment.This article has an associated First Person interview with the first author of the paper.
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Affiliation(s)
- Tejeshwar C Rao
- Department of Cell, Developmental, and Integrative Biology, University of Alabama at Birmingham, Birmingham, AL 35294, USA
| | | | - Aaron Blanchard
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, Atlanta, GA 30322, USA
| | - Tara M Urner
- Department of Cell, Developmental, and Integrative Biology, University of Alabama at Birmingham, Birmingham, AL 35294, USA
| | - Shreya Grandhi
- Department of Cell, Developmental, and Integrative Biology, University of Alabama at Birmingham, Birmingham, AL 35294, USA
| | - Khalid Salaita
- Department of Chemistry, Emory University, Atlanta, GA 30322, USA
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, Atlanta, GA 30322, USA
| | - Alexa L Mattheyses
- Department of Cell, Developmental, and Integrative Biology, University of Alabama at Birmingham, Birmingham, AL 35294, USA
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7
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Belli S, Esposito D, Servetto A, Pesapane A, Formisano L, Bianco R. c-Src and EGFR Inhibition in Molecular Cancer Therapy: What Else Can We Improve? Cancers (Basel) 2020; 12:E1489. [PMID: 32517369 PMCID: PMC7352780 DOI: 10.3390/cancers12061489] [Citation(s) in RCA: 33] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2020] [Revised: 06/02/2020] [Accepted: 06/04/2020] [Indexed: 02/06/2023] Open
Abstract
The proto-oncogene c-Src is a non-receptor tyrosine kinase playing a key role in many cellular pathways, including cell survival, migration and proliferation. c-Src de-regulation has been observed in several cancer types, making it an appealing target for drug discovery efforts. Recent evidence emphasizes its crucial role not only in promoting oncogenic traits, but also in the acquisition and maintenance of cancer resistance to various chemotherapeutic or molecular target drugs. c-Src modulates epidermal growth factor receptor (EGFR) activation and amplifies its downstream oncogenic signals. In this review, we report several studies supporting c-Src kinase role in the intricate mechanisms of resistance to EGFR tyrosine kinase inhibitors (TKIs). We further highlighted pre- and clinical progresses of combined treatment strategies made in recent years. Several pre-clinical data have encouraged the use of c-Src inhibitors in combination with EGFR inhibitors. However, clinical trials provided controversial outcomes in some cancer types. Despite c-Src inhibitors showed good tolerability in cancer patients, no incontrovertible and consistent clinical responses were recorded, supporting the idea that a better selection of patients is needed to improve clinical outcome. Currently, the identification of biological markers predictive of therapy response and the accurate molecular screening of cancer patients aimed to gain most clinical benefits become decisive and mandatory.
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Affiliation(s)
| | | | | | | | - Luigi Formisano
- Department of Clinical Medicine and Surgery, University of Naples “Federico II”, 80131 Naples, Italy; (S.B.); (D.E.); (A.S.); (A.P.)
| | - Roberto Bianco
- Department of Clinical Medicine and Surgery, University of Naples “Federico II”, 80131 Naples, Italy; (S.B.); (D.E.); (A.S.); (A.P.)
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8
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Akula SM, Candido S, Abrams SL, Steelman LS, Lertpiriyapong K, Cocco L, Ramazzotti G, Ratti S, Follo MY, Martelli AM, Murata RM, Rosalen PL, Bueno-Silva B, Matias de Alencar S, Falasca M, Montalto G, Cervello M, Notarbartolo M, Gizak A, Rakus D, Libra M, McCubrey JA. Abilities of β-Estradiol to interact with chemotherapeutic drugs, signal transduction inhibitors and nutraceuticals and alter the proliferation of pancreatic cancer cells. Adv Biol Regul 2020; 75:100672. [PMID: 31685431 DOI: 10.1016/j.jbior.2019.100672] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2019] [Revised: 10/12/2019] [Accepted: 10/15/2019] [Indexed: 06/10/2023]
Abstract
Improving the effects of chemotherapy and reducing the side effects are important goals in cancer research. Various approaches have been examined to enhance the effectiveness of chemotherapy. For example, signal transduction inhibitors or hormonal based approaches have been included with chemo- or radio-therapy. MIA-PaCa-2 and BxPC-3 pancreatic ductal adenocarcinoma (PDAC) cells both express the estrogen receptor (ER). The effects of β-estradiol on the growth of PDAC cells has not been examined yet the ER is expressed in PDAC cells. We have examined the effects of combining β-estradiol with chemotherapeutic drugs, signal transcription inhibitors, natural products and nutraceuticals on PDAC. In most cases, inclusion of β-estradiol with chemotherapeutic drugs increased chemosensitivity. These results indicate some approaches involving β-estradiol which may be used to increase the effectiveness of chemotherapeutic and other drugs on the growth of PDAC.
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Affiliation(s)
- Shaw M Akula
- Department of Microbiology and Immunology, Brody School of Medicine at East Carolina University, Greenville, NC, 27858, USA
| | - Saverio Candido
- Department of Biomedical and Biotechnological Sciences, Oncological, Clinical and General Pathology Section, University of Catania, Catania, Italy; Research Center for Prevention, Diagnosis and Treatment of Cancer (PreDiCT), University of Catania, Catania, Italy
| | - Stephen L Abrams
- Department of Microbiology and Immunology, Brody School of Medicine at East Carolina University, Greenville, NC, 27858, USA
| | - Linda S Steelman
- Department of Microbiology and Immunology, Brody School of Medicine at East Carolina University, Greenville, NC, 27858, USA
| | - Kvin Lertpiriyapong
- Center of Comparative Medicine and Pathology, Memorial Sloan-Kettering Cancer Center, Weill Cornell Medicine and the Hospital for Special Surgery, New York City, New York, USA
| | - Lucio Cocco
- Dipartimento di Scienze Biomediche e Neuromotorie, Università di Bologna, Bologna, Italy
| | - Giulia Ramazzotti
- Dipartimento di Scienze Biomediche e Neuromotorie, Università di Bologna, Bologna, Italy
| | - Stefano Ratti
- Dipartimento di Scienze Biomediche e Neuromotorie, Università di Bologna, Bologna, Italy
| | - Matilde Y Follo
- Dipartimento di Scienze Biomediche e Neuromotorie, Università di Bologna, Bologna, Italy
| | - Alberto M Martelli
- Dipartimento di Scienze Biomediche e Neuromotorie, Università di Bologna, Bologna, Italy
| | - Ramiro M Murata
- Department of Microbiology and Immunology, Brody School of Medicine at East Carolina University, Greenville, NC, 27858, USA; Department of Foundational Sciences, School of Dental Medicine, East Carolina University, USA
| | - Pedro L Rosalen
- Department of Physiological Sciences, Piracicaba Dental School, State University of Campinas, Piracicaba, Brazil
| | - Bruno Bueno-Silva
- Department of Physiological Sciences, Piracicaba Dental School, State University of Campinas, Piracicaba, Brazil; Dental Research Division, Guarulhos University, Guarulhos, Brazil
| | | | - Marco Falasca
- Metabolic Signalling Group, School of Pharmacy & Biomedical Sciences, Curtin Health Innovation Research Institute, Faculty of Health Sciences, Curtin University, Perth, Western Australia, 6102, Australia
| | - Giuseppe Montalto
- Dipartimento di Promozione Della Salute, Materno-Infantile, Medicina Interna e Specialistica di Eccellenza (PROMISE), University of Palermo, Palermo, Italy; Institute for Biomedical Research and Innovation, National Research Council (CNR), Palermo, Italy
| | - Melchiorre Cervello
- Institute for Biomedical Research and Innovation, National Research Council (CNR), Palermo, Italy
| | - Monica Notarbartolo
- Department of Biological, Chemical and Pharmaceutical Science and Technology (STEBICEF), University of Palermo, Palermo, Italy
| | - Agnieszka Gizak
- Department of Molecular Physiology and Neurobiology, Wroclaw University, Wroclaw, Poland
| | - Dariusz Rakus
- Department of Molecular Physiology and Neurobiology, Wroclaw University, Wroclaw, Poland
| | - Massimo Libra
- Department of Biomedical and Biotechnological Sciences, Oncological, Clinical and General Pathology Section, University of Catania, Catania, Italy; Research Center for Prevention, Diagnosis and Treatment of Cancer (PreDiCT), University of Catania, Catania, Italy
| | - James A McCubrey
- Department of Microbiology and Immunology, Brody School of Medicine at East Carolina University, Greenville, NC, 27858, USA.
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9
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Lopez Corcino Y, Gonzalez Ferrer S, Mantilla LE, Trikeriotis S, Yu JS, Kim S, Hansen S, Portillo JAC, Subauste CS. Toxoplasma gondii induces prolonged host epidermal growth factor receptor signalling to prevent parasite elimination by autophagy: Perspectives for in vivo control of the parasite. Cell Microbiol 2019; 21:e13084. [PMID: 31290228 PMCID: PMC6771541 DOI: 10.1111/cmi.13084] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2019] [Revised: 07/03/2019] [Accepted: 07/07/2019] [Indexed: 12/23/2022]
Abstract
Toxoplasma gondii causes retinitis and encephalitis. Avoiding targeting by autophagosomes is key for its survival because T. gondii cannot withstand lysosomal degradation. During invasion of host cells, T. gondii triggers epidermal growth factor receptor (EGFR) signalling enabling the parasite to avoid initial autophagic targeting. However, autophagy is a constitutive process indicating that the parasite may also use a strategy operative beyond invasion to maintain blockade of autophagic targeting. Finding that such a strategy exists would be important because it could lead to inhibition of host cell signalling as a novel approach to kill the parasite in previously infected cells and treat toxoplasmosis. We report that T. gondii induced prolonged EGFR autophosphorylation. This effect was mediated by PKCα/PKCβ ➔ Src because T. gondii caused prolonged activation of these molecules and their knockdown or incubation with inhibitors of PKCα/PKCβ or Src after host cell invasion impaired sustained EGFR autophosphorylation. Addition of EGFR tyrosine kinase inhibitor (TKI) to previously infected cells led to parasite entrapment by LC3 and LAMP-1 and pathogen killing dependent on the autophagy proteins ULK1 and Beclin 1 as well as lysosomal enzymes. Administration of gefitinib (EGFR TKI) to mice with ocular and cerebral toxoplasmosis resulted in disease control that was dependent on Beclin 1. Thus, T. gondii promotes its survival through sustained EGFR signalling driven by PKCα/β ➔ Src, and inhibition of EGFR controls pre-established toxoplasmosis.
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Affiliation(s)
| | - Shekina Gonzalez Ferrer
- Division of Infectious Diseases and HIV Medicine, Department of Medicine, Case Western Reserve University, Cleveland, Ohio, USA
| | | | - Sophia Trikeriotis
- Division of Infectious Diseases and HIV Medicine, Department of Medicine, Case Western Reserve University, Cleveland, Ohio, USA
| | - Jin-Sang Yu
- Division of Infectious Diseases and HIV Medicine, Department of Medicine, Case Western Reserve University, Cleveland, Ohio, USA
| | - Steven Kim
- Division of Infectious Diseases and HIV Medicine, Department of Medicine, Case Western Reserve University, Cleveland, Ohio, USA
| | - Samuel Hansen
- Division of Infectious Diseases and HIV Medicine, Department of Medicine, Case Western Reserve University, Cleveland, Ohio, USA
| | - Jose-Andres C Portillo
- Division of Infectious Diseases and HIV Medicine, Department of Medicine, Case Western Reserve University, Cleveland, Ohio, USA
| | - Carlos S Subauste
- Department of Pathology, Case Western Reserve University, Cleveland, Ohio, USA.,Division of Infectious Diseases and HIV Medicine, Department of Medicine, Case Western Reserve University, Cleveland, Ohio, USA
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10
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Ungewiß H, Rötzer V, Meir M, Fey C, Diefenbacher M, Schlegel N, Waschke J. Dsg2 via Src-mediated transactivation shapes EGFR signaling towards cell adhesion. Cell Mol Life Sci 2018; 75:4251-4268. [PMID: 29980799 PMCID: PMC11105603 DOI: 10.1007/s00018-018-2869-x] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2018] [Revised: 06/19/2018] [Accepted: 07/03/2018] [Indexed: 12/31/2022]
Abstract
Rapidly renewing epithelial tissues such as the intestinal epithelium require precise tuning of intercellular adhesion and proliferation to preserve barrier integrity. Here, we provide evidence that desmoglein 2 (Dsg2), an adhesion molecule of desmosomes, controls cell adhesion and proliferation via epidermal growth factor receptor (EGFR) signaling. Dsg2 is required for EGFR localization at intercellular junctions as well as for Src-mediated EGFR activation. Src binds to EGFR and is required for localization of EGFR and Dsg2 to cell-cell contacts. EGFR is critical for cell adhesion and barrier recovery. In line with this, Dsg2-deficient enterocytes display impaired barrier properties and increased cell proliferation. Mechanistically, Dsg2 directly interacts with EGFR and undergoes heterotypic-binding events on the surface of living enterocytes via its extracellular domain as revealed by atomic force microscopy. Thus, our study reveals a new mechanism by which Dsg2 via Src shapes EGFR function towards cell adhesion.
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Affiliation(s)
- Hanna Ungewiß
- Department I, Institute of Anatomy and Cell Biology, Ludwig Maximilians University Munich, Pettenkoferstr. 11, 80336, Munich, Germany
| | - Vera Rötzer
- Department I, Institute of Anatomy and Cell Biology, Ludwig Maximilians University Munich, Pettenkoferstr. 11, 80336, Munich, Germany
| | - Michael Meir
- Department of General, Visceral, Vascular and Paediatric Surgery, Julius-Maximilians-Universität, Oberdürrbacher Str. 6, 97080, Würzburg, Germany
| | - Christina Fey
- Department for Tissue Engineering and Regenerative Medicine, University Hospital Würzburg, Röntgenring 11, 97070, Würzburg, Germany
| | - Markus Diefenbacher
- Department of Biochemistry and Molecular Biochemistry, University of Würzburg, Am Hubland, 97074, Würzburg, Germany
| | - Nicolas Schlegel
- Department of General, Visceral, Vascular and Paediatric Surgery, Julius-Maximilians-Universität, Oberdürrbacher Str. 6, 97080, Würzburg, Germany
| | - Jens Waschke
- Department I, Institute of Anatomy and Cell Biology, Ludwig Maximilians University Munich, Pettenkoferstr. 11, 80336, Munich, Germany.
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Some Biological Consequences of the Inhibition of Na,K-ATPase by Translationally Controlled Tumor Protein (TCTP). Int J Mol Sci 2018; 19:ijms19061657. [PMID: 29867020 PMCID: PMC6032315 DOI: 10.3390/ijms19061657] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2018] [Revised: 05/29/2018] [Accepted: 05/30/2018] [Indexed: 12/17/2022] Open
Abstract
Na,K-ATPase is an ionic pump that regulates the osmotic equilibrium and membrane potential of cells and also functions as a signal transducer. The interaction of Na,K-ATPase with translationally controlled tumor protein (TCTP) results, among others, in the inhibition of the former's pump activity and in the initiation of manifold biological and pathological phenomena. These phenomena include hypertension and cataract development in TCTP-overexpressing transgenic mice, as well as the induction of tumorigenesis signaling pathways and the activation of Src that ultimately leads to cell proliferation and migration. This review attempts to collate the biological effects of Na,K-ATPase and TCTP interaction and suggests that this interaction has the potential to serve as a possible therapeutic target for selected diseases.
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Chen Z, Oh D, Dubey AK, Yao M, Yang B, Groves JT, Sheetz M. EGFR family and Src family kinase interactions: mechanics matters? Curr Opin Cell Biol 2018; 51:97-102. [DOI: 10.1016/j.ceb.2017.12.003] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2017] [Accepted: 12/11/2017] [Indexed: 01/23/2023]
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13
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Wang J, Tan M, Ge J, Zhang P, Zhong J, Tao L, Wang Q, Tong X, Qiu J. Lysosomal acid lipase promotes cholesterol ester metabolism and drives clear cell renal cell carcinoma progression. Cell Prolif 2018; 51:e12452. [PMID: 29569766 DOI: 10.1111/cpr.12452] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2017] [Accepted: 01/22/2018] [Indexed: 12/28/2022] Open
Abstract
OBJECTIVES Clear cell renal cell carcinoma (ccRCC) is characterized histologically by accumulation of cholesterol esters, cholesterol and other neutral lipids. Lysosomal acid lipase (LAL) is a critical enzyme involved in the cholesterol ester metabolism. Here, we sought to determine whether LAL could orchestrate metabolism of cholesterol esters in order to promote ccRCC progression. MATERIALS AND METHODS Quantitative reverse-transcription PCR and western blots were conducted to assess the expression of LAL in human ccRCC tissues. We analysed the relationship between LAL levels and patient survival using tissue microarrays. We used cell proliferation assays, colony formation assays, cell death assays, metabolic assays and xenograft tumour models to evaluate the biological function and underlying mechanisms. RESULTS LAL was up-regulated in ccRCC tissue. Tissue microarray analysis revealed higher levels of LAL in advanced grades of ccRCC, and high LAL expression indicated lower patient survival. Suppressing LAL expression not only blocked the utilization of cholesterol esters but also impaired proliferation and cellular survival. Furthermore, immunohistochemistry staining showed that LAL expression was correlated with Akt phosphorylation. Suppressing LAL expression decreased the phosphorylation level of Akt and Src and reduced the level of 14,15-epoxyeicosatrienoic acids in ccRCC cells. Supplement of 14,15-epoxyeicosatrienoic acids rescued proliferation in vitro and in vivo. CONCLUSIONS LAL promoted cell proliferation and survival via metabolism of epoxyeicosatrienoic acids and activation of the Src/Akt pathway.
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Affiliation(s)
- Jun Wang
- Department of Urology, School of Medicine, Shanghai General Hospital, Shanghai Jiao Tong University, Shanghai, China
| | - Mingyue Tan
- Department of Urology, School of Medicine, Shanghai General Hospital, Shanghai Jiao Tong University, Shanghai, China
| | - Jifu Ge
- Department of Urology, School of Medicine, Shanghai General Hospital, Shanghai Jiao Tong University, Shanghai, China
| | - Ping Zhang
- Shanghai Key Laboratory for Tumor Microenvironment and Inflammation, Key Laboratory of Cell Differentiation and Apoptosis of Chinese Ministry of Education, Department of Biochemistry and Molecular Cell Biology, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Jie Zhong
- Shanghai Key Laboratory for Tumor Microenvironment and Inflammation, Key Laboratory of Cell Differentiation and Apoptosis of Chinese Ministry of Education, Department of Biochemistry and Molecular Cell Biology, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Le Tao
- Department of Urology, School of Medicine, Shanghai General Hospital, Shanghai Jiao Tong University, Shanghai, China
| | - Qiong Wang
- Department of Clinical Laboratory, Wuxi People's Hospital Affiliated to Nanjing Medical University, Wuxi, Jiangsu, China
| | - Xuemei Tong
- Shanghai Key Laboratory for Tumor Microenvironment and Inflammation, Key Laboratory of Cell Differentiation and Apoptosis of Chinese Ministry of Education, Department of Biochemistry and Molecular Cell Biology, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Jianxin Qiu
- Department of Urology, School of Medicine, Shanghai General Hospital, Shanghai Jiao Tong University, Shanghai, China
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14
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Wang D, Liu C, Wang J, Jia Y, Hu X, Jiang H, Shao ZM, Zeng YA. Protein C receptor stimulates multiple signaling pathways in breast cancer cells. J Biol Chem 2017; 293:1413-1424. [PMID: 29217770 DOI: 10.1074/jbc.m117.814046] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2017] [Revised: 11/30/2017] [Indexed: 11/06/2022] Open
Abstract
The protein C receptor (PROCR) has emerged as a stem cell marker in several normal tissues and has also been implicated in tumor progression. However, the functional role of PROCR and the signaling mechanisms downstream of PROCR remain poorly understood. Here, we dissected the PROCR signaling pathways in breast cancer cells. Combining protein array, knockdown, and overexpression methods, we found that PROCR concomitantly activates multiple pathways. We also noted that PROCR-dependent ERK and PI3k-Akt-mTOR signaling pathways proceed through Src kinase and transactivation of insulin-like growth factor 1 receptor (IGF-1R). These pathway activities led to the accumulation of c-Myc and cyclin D1. On the other hand, PROCR-dependent RhoA-ROCK-p38 signaling relied on coagulation factor II thrombin receptor (F2R). We confirmed these findings in primary cells isolated from triple-negative breast cancer-derived xenografts (PDX) that have high expression of PROCR. To the best our knowledge, this is the first comprehensive study of PROCR signaling in breast cancer cells, and its findings also shed light on the molecular mechanisms of PROCR in stem cells in normal tissue.
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Affiliation(s)
- Daisong Wang
- From the State Key Laboratory of Cell Biology, CAS Center for Excellence in Molecular Cell Science, Institute of Biochemistry and Cell Biology, Chinese Academy of Sciences, Shanghai 200031, China
| | - Chunye Liu
- From the State Key Laboratory of Cell Biology, CAS Center for Excellence in Molecular Cell Science, Institute of Biochemistry and Cell Biology, Chinese Academy of Sciences, Shanghai 200031, China
| | - Jingqiang Wang
- From the State Key Laboratory of Cell Biology, CAS Center for Excellence in Molecular Cell Science, Institute of Biochemistry and Cell Biology, Chinese Academy of Sciences, Shanghai 200031, China
| | - Yingying Jia
- From the State Key Laboratory of Cell Biology, CAS Center for Excellence in Molecular Cell Science, Institute of Biochemistry and Cell Biology, Chinese Academy of Sciences, Shanghai 200031, China
| | - Xin Hu
- Key Laboratory of Breast Cancer in Shanghai, Department of Breast Surgery, Fudan University Shanghai Cancer Center, Department of Oncology, Shanghai Medical College, Fudan University, Shanghai 200032, China, and
| | - Hai Jiang
- Key Laboratory of Systems Biology, Innovation Center for Cell Signaling Network, Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200031, China
| | - Zhi-Ming Shao
- Key Laboratory of Breast Cancer in Shanghai, Department of Breast Surgery, Fudan University Shanghai Cancer Center, Department of Oncology, Shanghai Medical College, Fudan University, Shanghai 200032, China, and
| | - Yi Arial Zeng
- From the State Key Laboratory of Cell Biology, CAS Center for Excellence in Molecular Cell Science, Institute of Biochemistry and Cell Biology, Chinese Academy of Sciences, Shanghai 200031, China,
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Mohanty SK, Yagiz K, Pradhan D, Luthringer DJ, Amin MB, Alkan S, Cinar B. STAT3 and STAT5A are potential therapeutic targets in castration-resistant prostate cancer. Oncotarget 2017; 8:85997-86010. [PMID: 29156772 PMCID: PMC5689662 DOI: 10.18632/oncotarget.20844] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2017] [Accepted: 08/03/2017] [Indexed: 11/25/2022] Open
Abstract
Mechanisms of castration-resistant prostate cancer (CRPC) are not well understood, thus hindering rational-based drug design. Activation of STAT3/5A, key components of the JAK/STAT pathway, is implicated in aggressive PC, yet their clinical relevance in CRPC remains elusive. Here, we evaluated the possible role of STAT3/5A in CRPC using immunological, quantitative mRNA expression profiling, and pharmacological methods. We observed a strong nuclear immunoreactivity for STAT3 and STAT5A in 93% (n=14/15) and 80% (n=12/15) of CRPC cases, respectively, compared with benign prostatic hyperplasia (BPH). We demonstrated that PC cells express varying levels of STAT3 and STAT5A transcripts. In addition, we demonstrate that pimozide, a psychotropic drug and an indirect inhibitor of STAT5, attenuated PC cells growth, and induced apoptosis in a dose-dependent manner. Furthermore, our analysis of the PC public data revealed that the STAT3/5A genes were frequently amplified in metastatic CRPC. These findings suggest that STAT3/5A potentially serves as a predictive biomarker to evaluate the therapeutic efficacy of a cancer drug targeting the JAK/STAT pathway. Since the JAK/STAT and AR pathways are suggested to be functionally synergistic, inhibition of the JAK/STAT signaling alone or together with AR may lead to a novel treatment modality for patients with advanced PC.
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Affiliation(s)
- Sambit K. Mohanty
- Department of Pathology and Laboratory Medicine, Cedars-Sinai Medical Center, Los Angeles, CA 90048, USA
| | - Kader Yagiz
- Department of Hematology and Oncology, Cedars-Sinai Medical Center, Los Angeles, CA 90048, USA
| | - Dinesh Pradhan
- University of Pittsburgh Medical Center, Pittsburgh, PA 15238, USA
| | - Daniel J. Luthringer
- Department of Pathology and Laboratory Medicine, Cedars-Sinai Medical Center, Los Angeles, CA 90048, USA
| | - Mahul B. Amin
- Department of Pathology and Laboratory Medicine, University of Tennessee Health Sciences Center, Memphis, TN 38163, USA
| | - Serhan Alkan
- Department of Pathology and Laboratory Medicine, Cedars-Sinai Medical Center, Los Angeles, CA 90048, USA
| | - Bekir Cinar
- Department of Biological Sciences, The Center for Cancer Research and Therapeutic Development, Clark Atlanta University, Atlanta, GA 30314, USA
- Winship Cancer Institute, Emory University, Atlanta, GA 30322, USA
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16
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Portillo JAC, Muniz-Feliciano L, Lopez Corcino Y, Lee SJ, Van Grol J, Parsons SJ, Schiemman WP, Subauste CS. Toxoplasma gondii induces FAK-Src-STAT3 signaling during infection of host cells that prevents parasite targeting by autophagy. PLoS Pathog 2017; 13:e1006671. [PMID: 29036202 PMCID: PMC5658194 DOI: 10.1371/journal.ppat.1006671] [Citation(s) in RCA: 42] [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: 02/10/2017] [Revised: 10/26/2017] [Accepted: 09/26/2017] [Indexed: 02/01/2023] Open
Abstract
Targeting of Toxoplasma gondii by autophagy is an effective mechanism by which host cells kill the protozoan. Thus, the parasite must avoid autophagic targeting to survive. Here we show that the mammalian cytoplasmic molecule Focal Adhesion Kinase (FAK) becomes activated during invasion of host cells. Activated FAK appears to accompany the formation of the moving junction (as assessed by expression the parasite protein RON4). FAK activation was inhibited by approaches that impaired β1 and β3 integrin signaling. FAK caused activation of Src that in turn mediated Epidermal Growth Factor Receptor (EGFR) phosphorylation at the unique Y845 residue. Expression of Src-resistant Y845F EGFR mutant markedly inhibited ROP16-independent activation of STAT3 in host cells. Activation of FAK, Y845 EGFR or STAT3 prevented activation of PKR and eIF2α, key stimulators of autophagy. Genetic or pharmacologic inhibition of FAK, Src, EGFR phosphorylation at Y845, or STAT3 caused accumulation of the autophagy protein LC3 and LAMP-1 around the parasite and parasite killing dependent on autophagy proteins (ULK1 and Beclin 1) and lysosomal enzymes. Parasite killing was inhibited by expression of dominant negative PKR. Thus, T. gondii activates a FAK→Src→Y845-EGFR→STAT3 signaling axis within mammalian cells, thereby enabling the parasite to survive by avoiding autophagic targeting through a mechanism likely dependent on preventing activation of PKR and eIF2α.
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Affiliation(s)
- Jose-Andres C. Portillo
- Department of Medicine, Division of Infectious Disease and HIV Medicine, Case Western Reserve University School of Medicine, Cleveland, OH, United States of America
| | - Luis Muniz-Feliciano
- Department of Medicine, Division of Infectious Disease and HIV Medicine, Case Western Reserve University School of Medicine, Cleveland, OH, United States of America
- Department of Pathology, Case Western Reserve University School of Medicine, Cleveland, OH, United States of America
| | - Yalitza Lopez Corcino
- Department of Medicine, Division of Infectious Disease and HIV Medicine, Case Western Reserve University School of Medicine, Cleveland, OH, United States of America
- Department of Pathology, Case Western Reserve University School of Medicine, Cleveland, OH, United States of America
| | - So Jung Lee
- Department of Medicine, Division of Infectious Disease and HIV Medicine, Case Western Reserve University School of Medicine, Cleveland, OH, United States of America
| | - Jennifer Van Grol
- Department of Medicine, Division of Infectious Disease and HIV Medicine, Case Western Reserve University School of Medicine, Cleveland, OH, United States of America
- Department of Pathology, Case Western Reserve University School of Medicine, Cleveland, OH, United States of America
| | - Sarah J. Parsons
- Department of Microbiology and Cancer Center, University of Virginia, Charlottesville, VA, United States of America
| | - William P. Schiemman
- Case Comprehensive Cancer Center, Case Western Reserve University, Cleveland, OH, United States of America
| | - Carlos S. Subauste
- Department of Medicine, Division of Infectious Disease and HIV Medicine, Case Western Reserve University School of Medicine, Cleveland, OH, United States of America
- Department of Pathology, Case Western Reserve University School of Medicine, Cleveland, OH, United States of America
- * E-mail:
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17
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Chen YJ, Lin KN, Jhang LM, Huang CH, Lee YC, Chang LS. Gallic acid abolishes the EGFR/Src/Akt/Erk-mediated expression of matrix metalloproteinase-9 in MCF-7 breast cancer cells. Chem Biol Interact 2016; 252:131-40. [DOI: 10.1016/j.cbi.2016.04.025] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2016] [Revised: 03/27/2016] [Accepted: 04/13/2016] [Indexed: 11/26/2022]
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18
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Jiang H, Wu L, Chen J, Mishra M, Chawsheen HA, Zhu H, Wei Q. Sulfiredoxin Promotes Colorectal Cancer Cell Invasion and Metastasis through a Novel Mechanism of Enhancing EGFR Signaling. Mol Cancer Res 2015; 13:1554-66. [PMID: 26290602 DOI: 10.1158/1541-7786.mcr-15-0240] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2015] [Accepted: 08/11/2015] [Indexed: 01/07/2023]
Abstract
UNLABELLED Sulfiredoxin (SRXN1/Srx) is a multifunction enzyme with a primary antioxidant role of reducing the overoxidized inactive form of peroxiredoxins (Prxs). The function and mechanisms of Srx in cancer development are not well understood. Here, Srx is preferentially expressed in human colorectal cancer cells but not in normal colon epithelial cells. Loss-of-function studies demonstrate that knockdown of Srx in poorly differentiated colorectal cancer cells not only leads to the inhibition of colony formation and cell invasion in vitro, but also reduces tumor xenograft growth and represses metastasis to distal organs in a mouse orthotopic implantation model. Notably, exactly opposite effects were observed in gain-of-function experiments when Srx was ectopically expressed in well-differentiated colorectal cancer cells. Mechanistically, expression of Srx enhances the activation of MAPK signaling through increasing the C-terminal tyrosine phosphorylation levels of EGFR. This function of Srx is mediated through its inhibition of EGFR acetylation at K1037, a novel posttranslational modification of EGFR in human colorectal cancer cells identified by liquid chromatography-electrospray ionization-tandem mass spectrometry (LC/ESI/MS-MS) proteomic analysis. Furthermore, abolishment of K1037 acetylation in human colorectal cancer cells by site-specific mutagenesis leads to sustained activation of EGFR-MAPK signaling. Combined, these data reveal that Srx promotes colorectal cancer cell invasion and metastasis through a novel mechanism of enhancing EGFR signaling. IMPLICATIONS Sulfiredoxin is a critical oncogenic protein that can be used as a molecular target to develop therapeutics for patients with metastatic colorectal cancer.
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Affiliation(s)
- Hong Jiang
- Department of Toxicology and Cancer Biology, University of Kentucky College of Medicine, Lexington, Kentucky. The Markey Cancer Center, University of Kentucky College of Medicine, Lexington, Kentucky
| | - Lisha Wu
- Department of Toxicology and Cancer Biology, University of Kentucky College of Medicine, Lexington, Kentucky. The Markey Cancer Center, University of Kentucky College of Medicine, Lexington, Kentucky
| | - Jing Chen
- Molecular and Cellular Biochemistry, University of Kentucky College of Medicine, Lexington, Kentucky
| | - Murli Mishra
- Department of Toxicology and Cancer Biology, University of Kentucky College of Medicine, Lexington, Kentucky. The Markey Cancer Center, University of Kentucky College of Medicine, Lexington, Kentucky
| | - Hedy A Chawsheen
- Department of Toxicology and Cancer Biology, University of Kentucky College of Medicine, Lexington, Kentucky. The Markey Cancer Center, University of Kentucky College of Medicine, Lexington, Kentucky
| | - Haining Zhu
- Molecular and Cellular Biochemistry, University of Kentucky College of Medicine, Lexington, Kentucky
| | - Qiou Wei
- Department of Toxicology and Cancer Biology, University of Kentucky College of Medicine, Lexington, Kentucky. The Markey Cancer Center, University of Kentucky College of Medicine, Lexington, Kentucky.
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19
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Yeom SY, Nam DH, Park C. RRAD promotes EGFR-mediated STAT3 activation and induces temozolomide resistance of malignant glioblastoma. Mol Cancer Ther 2014; 13:3049-61. [PMID: 25313011 DOI: 10.1158/1535-7163.mct-14-0244] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Glioblastoma multiforme (GBM) is an extremely aggressive brain cancer with a median survival of less than 2 years. GBM is characterized by abnormal activation of receptor tyrosine kinase and constitutively activated STAT3. Although EGFR phosphorylation and STAT3 activation are essential for the maintenance of GBM cancer stem cells, the molecular mechanism underlying endosome-mediated STAT3 activation is not fully understood. In the current study, we showed that GTP-binding protein RRAD (RAS associated with diabetes, RAD) physically associates with EGFR, and EEA1, enhancing the stability and endosome-associated nuclear translocation of EGFR. Functionally, RRAD contributes to the activation of STAT3 and expression of the stem cell factors OCT4, NANOG, and SOX2, thereby enhancing self-renewing ability, tumor sphere formation, EMT, and in vivo tumorigenesis. Most importantly, RRAD contributes to poor survival in patients with GBM. RRAD expression is correlated with temozolomide resistance, and, conversely, depletion of RRAD leads to sensitization of highly temozolomide-resistant GBM cells. Our data collectively support a novel function of RRAD in STAT3 activation and provide evidence that RRAD acts as a positive regulator in the EGFR signaling pathway. These results demonstrate a critical role for RRAD in GBM tumorigenesis and provide a rationale for the development of pharmacologic inhibitors of RRAD in GBM.
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Affiliation(s)
- Seon-Yong Yeom
- Research Institute for Future Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea
| | - Do-Hyun Nam
- Department of Neurosurgery, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea
| | - Chaehwa Park
- Research Institute for Future Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.
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Baro M, de Llobet LI, Figueras A, Skvortsova I, Mesia R, Balart J. Dasatinib worsens the effect of cetuximab in combination with fractionated radiotherapy in FaDu- and A431-derived xenografted tumours. Br J Cancer 2014; 111:1310-8. [PMID: 25077442 PMCID: PMC4183853 DOI: 10.1038/bjc.2014.432] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Revised: 06/02/2014] [Accepted: 07/09/2014] [Indexed: 12/24/2022] Open
Abstract
Background: Cetuximab is often combined with radiotherapy in advanced SCCHN. Alternative routes bypassing inhibition of EGFR with cetuximab may overshadow the efficacy of this combination. We undertook this study to investigate a possible role of dasatinib in this scenario. Methods: The SCC5, SCC25, SCC29, FaDu and A431 cell lines were assessed in vitro for cell proliferation under cetuximab and dasatinib treatments. In FaDu and A431 cells, dasatinib plus cetuximab resulted in higher proliferation than cetuximab alone. Then, FaDu and A431 cells were implanted into subcutaneous tissue of athymic mice that were irradiated with 30 Gy in 10 fractions over 2 weeks, and treated with cetuximab and dasatinib. Tumour growth, DNA synthesis and angiogenesis were determined. The EGFR, RAS-GTP activity, phosphorylated AKT, ERK1/2, SRC protein levels and VEGF secretion were determined in vitro. Results: The addition of dasatinib to cetuximab and radiotherapy increased tumour growth, DNA synthesis and angiogenesis that were associated with RAS, AKT and ERK1/2 activation, and SRC inhibition in FaDu and A431 cells. Conclusions: In xenografts derived from these two cell lines, dasatinib did not improve the efficacy of cetuximab combined with radiotherapy. On the contrary, it worsened tumour control achieved by the combination of these two treatments.
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Affiliation(s)
- M Baro
- Laboratory of Translational Research, Catalan Institute of Oncology, Avda. Gran de L'Hospitalet 199-203, 08907 L'Hospitalet de Llobregat, Spain
| | - L I de Llobet
- Laboratory of Translational Research, Catalan Institute of Oncology, Avda. Gran de L'Hospitalet 199-203, 08907 L'Hospitalet de Llobregat, Spain
| | - A Figueras
- Laboratory of Translational Research, Catalan Institute of Oncology, Avda. Gran de L'Hospitalet 199-203, 08907 L'Hospitalet de Llobregat, Spain
| | - I Skvortsova
- Department of Therapeutic Radiology and Oncology, Innsbruck Medical University, Anichstrasse 35, 6020 Innsbruck, Austria
| | - R Mesia
- Department of Medical Oncology, Catalan Institute of Oncology, Avda. Gran de L'Hospitalet 199-203, 08907 L'Hospitalet de Llobregat, Spain
| | - J Balart
- 1] Laboratory of Translational Research, Catalan Institute of Oncology, Avda. Gran de L'Hospitalet 199-203, 08907 L'Hospitalet de Llobregat, Spain [2] Department of Radiation Oncology, Hospital de la Santa Creu i Sant Pau, Sant Antoni Maria Claret 167, 08025 Barcelona, Spain
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Williams KC, Coppolino MG. SNARE-dependent interaction of Src, EGFR and β1 integrin regulates invadopodia formation and tumor cell invasion. J Cell Sci 2014; 127:1712-25. [PMID: 24496451 DOI: 10.1242/jcs.134734] [Citation(s) in RCA: 55] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
Acquisition of an invasive phenotype is prerequisite for tumor metastasis. Degradation of the extracellular matrix (ECM), and subsequent invasion by tumor cells, is mediated, in part, through subcellular structures called invadopodia. Src-dependent cytoskeletal rearrangements are required to form invadopodia, and here we identify an association between Src, epidermal growth factor receptor (EGFR), and β1 integrin that facilitates invadopodia formation. The association of Src, EGFR and β1 integrin is dependent upon membrane traffic that is mediated by syntaxin13 (officially known as STX12) and SNAP23; a similar dependence on these two SNARE proteins was observed for invadopodium-based matrix degradation and cell invasion. Inhibition of SNARE function impaired the delivery of Src and EGFR to developing invadopodia, as well as the β1-integrin-dependent activation of Src and phosphorylation of EGFR on Tyr residue 845. We also identified an association between SNAP23 and β1 integrin, and inhibition of β1 integrin increased this association, whereas the interaction between syntaxin13 and SNAP23 was reduced. The results suggest that SNARE-dependent trafficking is regulated, in part, by β1 integrin and is required for the delivery of Src and EGFR to sites of invadopodia formation in order to support tumor cell invasion.
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Affiliation(s)
- Karla C Williams
- Department of Molecular and Cellular Biology, University of Guelph, Guelph, ON N1G 2W1, Canada
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Cellular functions regulated by phosphorylation of EGFR on Tyr845. Int J Mol Sci 2013; 14:10761-90. [PMID: 23702846 PMCID: PMC3709701 DOI: 10.3390/ijms140610761] [Citation(s) in RCA: 72] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2013] [Revised: 05/06/2013] [Accepted: 05/13/2013] [Indexed: 11/17/2022] Open
Abstract
The Src gene product (Src) and the epidermal growth factor receptor (EGFR) are prototypes of oncogene products and function primarily as a cytoplasmic non-receptor tyrosine kinase and a transmembrane receptor tyrosine kinase, respectively. The identification of Src and EGFR, and the subsequent extensive investigations of these proteins have long provided cutting edge research in cancer and other molecular and cellular biological studies. In 1995, we reported that the human epidermoid carcinoma cells, A431, contain a small fraction of Src and EGFR in which these two kinase were in physical association with each other, and that Src phosphorylates EGFR on tyrosine 845 (Y845) in the Src-EGFR complex. Y845 of EGFR is located in the activation segment of the kinase domain, where many protein kinases contain kinase-activating autophosphorylation sites (e.g., cAMP-dependent protein kinase, Src family kinases, transmembrane receptor type tyrosine kinases) or trans-phosphorylation sites (e.g., cyclin-dependent protein kinase, mitogen-activated protein kinase, Akt protein kinase). A number of studies have demonstrated that Y845 phosphorylation serves an important role in cancer as well as normal cells. Here we compile the experimental facts involving Src phosphorylation of EGFR on Y845, by which cell proliferation, cell cycle control, mitochondrial regulation of cell metabolism, gamete activation and other cellular functions are regulated. We also discuss the physiological relevance, as well as structural insights of the Y845 phosphorylation.
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Intercellular contact augments epidermal growth factor receptor (EGFR) and signal transducer and activator of transcription 3 (STAT3)-activation which increases podoplanin-expression in order to promote squamous cell carcinoma motility. Cell Signal 2013; 25:760-5. [DOI: 10.1016/j.cellsig.2012.12.004] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2012] [Accepted: 12/18/2012] [Indexed: 01/13/2023]
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Zhang X, Meng J, Wang ZY. A switch role of Src in the biphasic EGF signaling of ER-negative breast cancer cells. PLoS One 2012; 7:e41613. [PMID: 22927910 PMCID: PMC3424221 DOI: 10.1371/journal.pone.0041613] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2012] [Accepted: 06/22/2012] [Indexed: 11/18/2022] Open
Abstract
It is well established that epidermal growth factor (EGF) is a potent mitogen in cells expressing EGF receptor (EGFR). However, a body of evidence indicated that the effects of mitogenic EGF signaling exhibit a non-monotonic, or biphasic dose response curve; EGF at low concentrations elicits a mitogenic signaling pathway to stimulate cell proliferation while at high concentrations, EGF inhibits cell growth. However, the molecular mechanism underlying this paradoxical effect of EGF on cell proliferation remains largely unknown. Here, we investigated the molecular mechanisms underlying the biphasic EGF signaling in ER-negative breast cancer MDA-MB-231 and MDA-MB-436 cells, both of which express endogenous EGFR. We found that EGF at low concentrations induced the phosphorylation of the Src-Y416 residue, an event to activate Src, while at high concentrations allowed Src-Y527 phosphorylation that inactivates Src. EGF at 10 ng/ml also induced phosphorylation of the MAPK/ERK and activated cyclin D1 promoter activity through the Src/EGFR/STAT5 pathways but not at a higher concentration (500 ng/ml). Our results thus demonstrated that Src functions as a switch of EGF signaling depending on concentrations of EGF.
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Affiliation(s)
- XinTian Zhang
- Department of Medical Microbiology and Immunology, Creighton University Medical School, Omaha, Nebraska, United States of America
| | - Jun Meng
- Department of Medical Microbiology and Immunology, Creighton University Medical School, Omaha, Nebraska, United States of America
| | - Zhao-Yi Wang
- Department of Medical Microbiology and Immunology, Creighton University Medical School, Omaha, Nebraska, United States of America
- * E-mail:
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Klein R, Stiller S, Gashaw I. Epidermal growth factor upregulates endometrial CYR61 expression via activation of the JAK2/STAT3 pathway. Reprod Fertil Dev 2012; 24:482-9. [PMID: 22401280 DOI: 10.1071/rd10335] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2010] [Accepted: 08/09/2011] [Indexed: 01/22/2023] Open
Abstract
Endometrial cysteine-rich protein 61 (CYR61, CCN1) is a growth factor-inducible gene whose expression is elevated during the proliferative phase of the menstrual cycle and which has been implicated in the pathogenesis of endometriosis. This study aimed to define the mediators of epidermal growth factor (EGF) signalling on CYR61 expression in spontaneously immortalised human endometrial epithelial cells (HES) as a model system. After 30 min of EGF treatment, the receptor was phosphorylated and internalised as well as mRNA CYR61 increased in HES cells. However, neither inhibition of C-terminal EGF receptor (EGFR)-phosphorylation nor blockage of the mitogen-activated proteinkinase/extracellular signal-regulated kinase (MAPK/ERK) pathway was able to reduce CYR61 levels. Surprisingly, the HES cells showed upregulation of CYR61 mRNA expression after inhibition of the MAPK/ERK pathway when treated with EGF. Specific inhibitor studies identified the contribution of Janus kinase 2 (JAK2) and the signal transducer and activator of transcription protein STAT3 to the regulation of CYR61 expression. The JAK2/STAT3 interaction contributed to the basal expression of CYR61 and mediated EGF-driven regulation of CYR61 after 30 and 120 min of treatment. In summary, EGF-mediated CYR61 upregulation in HES cells involves STAT3 and is counter-regulated by the EGFR/MAPK/ERK pathway.
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Affiliation(s)
- Rebecca Klein
- University of Duisburg-Essen, Institute of Anatomy II, Hufelandstraße 55, 45122 Essen, Germany
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Yates TJ, Knapp J, Gosalbez M, Lokeshwar SD, Gomez CS, Benitez A, Ekwenna OO, Young EE, Manoharan M, Lokeshwar VB. C-X-C chemokine receptor 7: a functionally associated molecular marker for bladder cancer. Cancer 2012; 119:61-71. [PMID: 22736438 DOI: 10.1002/cncr.27661] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2011] [Revised: 04/11/2012] [Accepted: 04/16/2012] [Indexed: 11/06/2022]
Abstract
BACKGROUND C-X-C chemokine receptor 4 (CXCR4) and CXCR7 are 7-transmembrane chemokine receptors of the stroma-derived factor (SDF-1). CXCR4, but not CXCR7, has been examined in bladder cancer (BCa). This study examined the functional and clinical significance of CXCR7 in BCa. METHODS CXCR4 and CXCR7 levels were measured in BCa cell lines, tissues (normal = 25; BCa = 44), and urine specimens (n = 186) by quantitative polymerase chain reaction and/or immunohistochemistry. CXCR7 function in BCa cells were examined by transient transfections using a CXCR7 expression vector or small interfering RNA. RESULTS In BCa cell lines, CXCR7 messenger RNA levels were 5- to 37-fold higher than those for CXCR4. Transient overexpression of CXCR7 in BCa cell lines promoted growth and chemotactic motility. CXCR7 colocalized and formed a functional complex with epidermal growth factor receptor, phosphoinositide 3-kinase/Akt, Erk, and src and induced their phosphorylation. CXCR7 also induced up-regulation of cyclin-D1 and bcl-2. Suppression of CXCR7 expression reversed these effects and induced apoptosis. CXCR7 messenger RNA levels and CXCR7 staining scores were significantly (5- to 10-fold) higher in BCa tissues than in normal tissues (P < .001). CXCR7 expression independently associated with metastasis (P = .019) and disease-specific mortality (P = .03). CXCR7 was highly expressed in endothelial cells in high-grade BCa tissues when compared to low-grade BCa and normal bladder. CXCR7 levels were elevated in exfoliated urothelial cells from high-grade BCa patients (P = .0001; 90% sensitivity; 75% specificity); CXCR4 levels were unaltered. CONCLUSIONS CXCR7 promotes BCa cell proliferation and motility plausibly through epidermal growth factor receptor receptor and Akt signaling. CXCR7 expression is elevated in BCa tissues and exfoliated cells and is associated with high-grade and metastasis.
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Affiliation(s)
- Travis J Yates
- Sheila and David Fuente Graduate Program in Cancer Biology, Sylvester Comprehensive Cancer Center, University of Miami School of Medicine, Florida, USA
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27
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Tseng HY, Liu ZM, Huang HS. NADPH oxidase-produced superoxide mediates EGFR transactivation by c-Src in arsenic trioxide-stimulated human keratinocytes. Arch Toxicol 2012; 86:935-45. [PMID: 22532027 DOI: 10.1007/s00204-012-0856-9] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2011] [Accepted: 04/11/2012] [Indexed: 01/08/2023]
Abstract
Arsenic is a well-known poison and carcinogen in humans. However, it also has been used to effectively treat some human cancers and non-carcinogenic ailments. Previously, we demonstrated in keratinocytes that arsenic trioxide (ATO)-induced p21(WAF1/CIP1) (p21) expression leading to cellular cytotoxicity through the c-Src/EGFR/ERK pathway and generation of reactive oxygen species (ROS). In this study, we found that EGFR-Y845 and EGFR-Y1173 could be phosphorylated by ATO. Using confocal microscopy and flow cytometry, we found that pretreatment with apocynin, DPI, and tiron could remove ATO-induced ROS production. Furthermore, to increase NADPH oxidase activity, ATO could induce cytosolic p67(phox) expression and translocation to membrane. In addition, knockdown of p67(phox) could abolish ATO-induced ROS production. Therefore, we suggest that NADPH oxidase-produced superoxide was a major source of ATO-induced ROS production. Conversely, ATO-induced NADPH oxidase activation and superoxide generation could be inhibited by the c-Src inhibitor PP1, but not by the EGFR inhibitor PD153035. In addition, overexpression of c-Src as well as treatment with ATO could stimulate EGFR-Y845/ERK phosphorylation, p21 expression, and cellular arrest/apoptosis, which could be attenuated by pretreatment with apocynin or knockdown of p67(phox). Collectively, we suggest that NADPH oxidase was involved in the ATO-induced arrest/apoptosis of keratinocytes, which was regulated by c-Src activation.
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Affiliation(s)
- Hong-Yu Tseng
- Department of Medical Laboratory Science and Biotechnology, College of Medicine, National Cheng Kung University, Tainan 701, Taiwan
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Marschall ALJ, Frenzel A, Schirrmann T, Schüngel M, Dübel S. Targeting antibodies to the cytoplasm. MAbs 2011; 3:3-16. [PMID: 21099369 DOI: 10.4161/mabs.3.1.14110] [Citation(s) in RCA: 87] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
A growing number of research consortia are now focused on generating antibodies and recombinant antibody fragments that target the human proteome. A particularly valuable application for these binding molecules would be their use inside a living cell, e.g., for imaging or functional intervention. Animal-derived antibodies must be brought into the cell through the membrane, whereas the availability of the antibody genes from phage display systems allows intracellular expression. Here, the various technologies to target intracellular proteins with antibodies are reviewed.
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Affiliation(s)
- Andrea L J Marschall
- Technische Universität Braunschweig; Institute of Biochemistry and Biotechnology; Braunschweig, Germany
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Kong L, Deng Z, Shen H, Zhang Y. Src family kinase inhibitor PP2 efficiently inhibits cervical cancer cell proliferation through down-regulating phospho-Src-Y416 and phospho-EGFR-Y1173. Mol Cell Biochem 2010; 348:11-9. [PMID: 21052789 DOI: 10.1007/s11010-010-0632-1] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2010] [Accepted: 10/18/2010] [Indexed: 11/26/2022]
Abstract
Tyrosine (Y) kinases inhibitors have been approved for targeted treatment of cancer. However, their clinical use is limited to some cancers and the mechanism of their action remains unclear. Previous study has indicated that PP2, a selective inhibitor of the Src family of non-receptor tyrosine kinases (nRTK), efficiently repressed cervical cancer growth in vitro and in vivo. In this regard, our aims are to explore the mechanism of PP2 on cervical cancer cell growth inhibition by investigating the suppressive divergence among PP1, PP2, and a negative control compound PP3. MTT results showed that three compounds had different inhibitory effects on proliferation of two cervical cancer cells, HeLa and SiHa, and PP2 was most efficient in a time- and dose-dependent manner. Moreover, we found 10 μM PP2 down-regulated pSrc-Y416 (P < 0.05), pEGFR-Y845 (P < 0.05), and -Y1173 (P < 0.05) expression levels, while 10 μM PP1 down-regulated pSrc-Y416 (P < 0.05) and pEGFR-Y845 (P < 0.05), but not pEGFR-Y1173; 10 μM PP3 down-regulated only pEGFR-Y1173 (P < 0.05). PP2 could modulate cell cycle arrest by up-regulating p21(Cip1) and p27(Kip1) in both HeLa and SiHa cells and down-regulating expression of cyclin A, and cyclin dependent kinase-2, -4 (Cdk-2, -4) in HeLa and of cyclin B and Cdk-2 in SiHa. Our results indicate that Src pathway and EGFR pathway play different roles in the proliferation of cervical cancer cells and PP2 efficiently reduces cervical cancer cell proliferation by reduction of both Src and EGFR activity.
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Affiliation(s)
- Lu Kong
- Department of Biochemistry and Molecular Biology, Cancer Institute, Capital Medical University, Beijing, China
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30
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Taiwan cobra cardiotoxin III inhibits Src kinase leading to apoptosis and cell cycle arrest of oral squamous cell carcinoma Ca9-22 cells. Toxicon 2010; 56:508-20. [DOI: 10.1016/j.toxicon.2010.05.007] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2010] [Revised: 05/05/2010] [Accepted: 05/07/2010] [Indexed: 11/22/2022]
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31
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Dewaele B, Floris G, Finalet-Ferreiro J, Fletcher CD, Coindre JM, Guillou L, Hogendoorn PCW, Wozniak A, Vanspauwen V, Schöffski P, Marynen P, Vandenberghe P, Sciot R, Debiec-Rychter M. Coactivated platelet-derived growth factor receptor {alpha} and epidermal growth factor receptor are potential therapeutic targets in intimal sarcoma. Cancer Res 2010; 70:7304-14. [PMID: 20685895 DOI: 10.1158/0008-5472.can-10-1543] [Citation(s) in RCA: 66] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Intimal sarcoma (IS) is a rare, malignant, and aggressive tumor that shows a relentless course with a concomitant low survival rate and for which no effective treatment is available. In this study, 21 cases of large arterial blood vessel IS were analyzed by immunohistochemistry and fluorescence in situ hybridization and selectively by karyotyping, array comparative genomic hybridization, sequencing, phospho-kinase antibody arrays, and Western immunoblotting in search for novel diagnostic markers and potential molecular therapeutic targets. Ex vivo immunoassays were applied to test the sensitivity of IS primary tumor cells to the receptor tyrosine kinase (RTK) inhibitors imatinib and dasatinib. We showed that amplification of platelet-derived growth factor receptor α (PDGFRA) is a common finding in IS, which should be considered as a molecular hallmark of this entity. This amplification is consistently associated with PDGFRA activation. Furthermore, the tumors reveal persistent activation of the epidermal growth factor receptor (EGFR), concurrent to PDGFRA activation. Activated PDGFRA and EGFR frequently coexist with amplification and overexpression of the MDM2 oncogene. Ex vivo immunoassays on primary IS cells from one case showed the potency of dasatinib to inhibit PDGFRA and downstream signaling pathways. Our findings provide a rationale for investigating therapies that target PDGFRA, EGFR, or MDM2 in IS. Given the clonal heterogeneity of this tumor type and the potential cross-talk between the PDGFRA and EGFR signaling pathways, targeting multiple RTKs and aberrant downstream effectors might be required to improve the therapeutic outcome for patients with this disease.
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Affiliation(s)
- Barbara Dewaele
- Department of Human Genetics, University of Leuven, Herestraat 49, B-3000 Leuven, Belgium
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Maruko A, Ohtake Y, Kawaguchi M, Kobayashi T, Baba T, Kuwahara Y, Nakagawa H, Shimura T, Fukumoto M, Ohkubo Y. X-radiation-induced down-regulation of the EGF receptor in primary cultured rat hepatocytes. Radiat Res 2010; 173:620-8. [PMID: 20426661 DOI: 10.1667/rr1793.1] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
Exposure to X radiation is associated with a decline in the proliferative activity of the liver, but the molecular mechanism(s) is not well understood. We investigated whether exposure to X radiation is involved in functional changes in the epidermal growth factor (EGF) receptor (EGFR), thereby causing a reduction of EGF-induced DNA synthesis using periportal hepatocytes (PPH) and perivenous hepatocytes (PVH), which differ in their proliferative activity. X radiation dose-dependently decreased DNA synthesis in both subpopulations. The rate of decline in the DNA synthesis was greater in PPH than in PVH, but the zonal difference disappeared after exposure to 10 Gy X radiation. [(125)I]EGF binding studies indicated that high-affinity EGFRs in both subpopulations were down-regulated after X irradiation. Furthermore, EGF-induced EGFR dimerization and phosphorylation at Y1173 in both subpopulations were down-regulated after X irradiation, and the rate of decline was greater in PPH than in PVH. In contrast, phosphorylation at Y845 after EGF treatment was dose-dependently up-regulated after X irradiation in both subpopulations. These results suggest that the X-radiation-related decline in EGF-induced DNA synthesis is caused at least partly by the modification of EGFR function.
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Affiliation(s)
- Akiko Maruko
- Department of Radiopharmacy, Tohoku Pharmaceutical University, 4-4-1, Komatsushima, Aoba-ku, Sendai, Miyagi 981-8558, Japan
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33
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An in vitro analysis of mechanical wounding-induced ligand-independent KGFR activation. J Dermatol Sci 2009; 53:182-91. [DOI: 10.1016/j.jdermsci.2008.10.008] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2008] [Revised: 10/01/2008] [Accepted: 10/14/2008] [Indexed: 11/20/2022]
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Molli PR, Adam L, Kumar R. Therapeutic IMC-C225 antibody inhibits breast cancer cell invasiveness via Vav2-dependent activation of RhoA GTPase. Clin Cancer Res 2008; 14:6161-70. [PMID: 18829495 DOI: 10.1158/1078-0432.ccr-07-5288] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
PURPOSE Abnormalities in the expression and signaling pathways downstream of epidermal growth factor receptor (EGFR) contribute to progression, invasion, and maintenance of the malignant phenotype in human cancers. Accordingly, biological agents, such as the EGFR-blocking antibody IMC-C225 have promising anticancer potential and are currently in various stages of clinical development. Because use of IMC-C225 is limited, at present, only for treatment of cancer with high EGFR expression, the goal of the present study was to determine the effect of IMC-C225 on the invasiveness of breast cancer cells with high and low levels of EGFR expression. EXPERIMENTAL DESIGN The effect of IMC-C225 on invasion was studied using breast cancer cell lines with high and low levels of EGFR expression. RESULTS The addition of EGF led to progressive stress fiber dissolution. In contrast, cells treated with IMC-C225 showed reduced invasiveness and increased stress-fiber formation. Interestingly, IMC-C225 pretreatment was accompanied by EGFR phosphorylation, as detected using an anti-phosphorylated tyrosine antibody (PY99), which correlated with phosphorylation of Vav2 guanine nucleotide exchange factor and activation of RhoA GTPase irrespective of EGFR level, and Vav2 interacted with EGFR only in IMC-C225-treated cells. The underlying mechanism involved an enhanced interaction between beta1 integrins and EGFR upon IMC-C225 treatment. CONCLUSION Here, we defined a new mechanism for IMC-C225 that cross-links integrins with EGFR, leading to activation of RhoA and inhibition of breast cancer cell invasion irrespective of the level of EGFR in the cells, thus providing a rationale for using IMC-C225 in the metastatic setting independent of the levels of EGFR.
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Affiliation(s)
- Poonam R Molli
- Department of Molecular and Cellular Oncology, University of Texas M. D. Anderson Cancer Center, 1515 Holcombe Boulevard, Houston, TX 77030, USA
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Morgan MA, Parsels LA, Kollar LE, Normolle DP, Maybaum J, Lawrence TS. The combination of epidermal growth factor receptor inhibitors with gemcitabine and radiation in pancreatic cancer. Clin Cancer Res 2008; 14:5142-9. [PMID: 18698032 DOI: 10.1158/1078-0432.ccr-07-4072] [Citation(s) in RCA: 105] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
PURPOSE Gemcitabine-radiotherapy is a standard treatment for locally advanced pancreatic cancer. Clinical data have shown that gemcitabine plus erlotinib is superior to gemcitabine alone for advanced pancreatic cancer. Therefore, we investigated the effects of the combination of epidermal growth factor receptor inhibitors with gemcitabine and radiation on a pancreatic cancer model. EXPERIMENTAL DESIGN EGFR signaling was analyzed by measuring phosphorylated EGFR (pEGFR(Y845, (Y1173)) and AKT (pAKT(S473)) protein levels in pancreatic cancer cell lines and tumors. The effects of scheduling on gemcitabine-mediated cytotoxicity and radiosensitization combined with erlotinib were determined by clonogenic survival. In vivo, the effects of cetuximab or erlotinib in combination with gemcitabine-radiation on the growth of BxPC-3 tumor xenografts were measured. RESULTS We found in vitro that gemcitabine induced phosphorylation of EGFR at Y845 and Y1173 that was blocked by erlotinib. Treatment of BxPC-3 cells with gemcitabine before erlotinib enhanced gemcitabine-mediated cytotoxicity without abrogating radiosensitization. In vivo, cetuximab or erlotinib in combination with gemcitabine-radiation inhibited growth compared with gemcitabine-radiation (time to tumor doubling: gemcitabine + radiation, 19 +/- 3 days; cetuximab + gemcitabine + radiation, 30 +/- 3 days; P < 0.05, erlotinib + gemcitabine + radiation 28 +/- 3 days; P < 0.1). Cetuximab or erlotinib in combination with gemcitabine-radiation resulted in significant inhibition of pEGFR(Y1173) and pAKT(S473) early in treatment, and pEGFR(Y845), pEGFR(Y1173), and pAKT(S473) by the end of treatment. This study shows a novel difference pEGFR(Y845) and pEGFR(Y1173) in response to EGFR inhibition. CONCLUSIONS These results show that the EGFR inhibitors cetuximab and erlotinib increase the efficacy of gemcitabine-radiation. This work supports the integration of EGFR inhibitors with gemcitabine-radiation in clinical trials for pancreatic cancer.
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Affiliation(s)
- Meredith A Morgan
- Department of Radiation Oncology, University of Michigan, Ann Arbor, Michigan 48109-5637, USA.
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Durmuş Tekir S, Yalçin Arga K, Ulgen KO. Drug targets for tumorigenesis: insights from structural analysis of EGFR signaling network. J Biomed Inform 2008; 42:228-36. [PMID: 18790083 DOI: 10.1016/j.jbi.2008.08.008] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2007] [Revised: 07/15/2008] [Accepted: 08/17/2008] [Indexed: 02/01/2023]
Abstract
Deciphering the complex network structure is crucial in drug target identification. This study presents a framework incorporating graph theoretic and network decomposition methods to analyze system-level properties of the comprehensive map of the epidermal growth factor receptor (EGFR) signaling, which is a good candidate model system to study the general mechanisms of signal transduction. The graph theoretic analysis of the EGFR network indicates that it has small-world characteristics with scale-free topology. The employment of network decomposition analysis enlightened the system-level properties, such as network cross-talk, specific molecules in each pathway and participation of molecules in the network. Participating in a significant fraction of the fundamental paths connecting the ligands to the phenotypes, cofactor GTP and complex Gbeta/Ggamma were identified as "housekeeping" molecules, through which all pathways of EGFR network are cross-talking. c-Src-Shc complex is identified as important due to its role in all fundamental paths through tumorigenesis and being specific to this phenotype. Inhibitors of this complex may be good anti-cancer agents having very little or no effect on other phenotypes.
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Affiliation(s)
- Saliha Durmuş Tekir
- Department of Chemical Engineering, Boğaziçi University, 34342 Bebek-Istanbul, Turkey.
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Superoxide dismutase 1 (SOD1) is essential for H2O2-mediated oxidation and inactivation of phosphatases in growth factor signaling. Proc Natl Acad Sci U S A 2008; 105:7147-52. [PMID: 18480265 DOI: 10.1073/pnas.0709451105] [Citation(s) in RCA: 183] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Superoxide dismutase 1 (SOD1) is an abundant copper/zinc enzyme found in the cytoplasm that converts superoxide into hydrogen peroxide and molecular oxygen. Tetrathiomolybdate (ATN-224) has been recently identified as an inhibitor of SOD1 that attenuates FGF-2- and VEGF-mediated phosphorylation of ERK1/2 in endothelial cells. However, the mechanism for this inhibition was not elucidated. Growth factor (GF) signaling elicits an increase in reactive oxygen species (ROS), which inactivates protein tyrosine phosphatases (PTP) by oxidizing an essential cysteine residue in the active site. ATN-224-mediated inhibition of SOD1 in tumor and endothelial cells prevents the formation of sufficiently high levels of H(2)O(2), resulting in the protection of PTPs from H(2)O(2)-mediated oxidation. This, in turn, leads to the inhibition of EGF-, IGF-1-, and FGF-2-mediated phosphorylation of ERK1/2. Pretreatment with exogenous H(2)O(2) or with the phosphatase inhibitor vanadate abrogates the inhibition of ERK1/2 phosphorylation induced by ATN-224 or SOD1 siRNA treatments. Furthermore, ATN-224-mediated SOD1 inhibition causes the down-regulation of the PDGF receptor. SOD1 inhibition also increases the steady-state levels of superoxide, which induces protein oxidation in A431 cells but, surprisingly, does not oxidize phosphatases. Thus, SOD1 inhibition in A431 tumor cells results in both prooxidant effects caused by the increase in the levels of superoxide and antioxidant effects caused by lowering the levels of H(2)O(2). These results identify SOD1 as a master regulator of GF signaling and as a therapeutic target for the inhibition of angiogenesis and tumor growth.
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An essential role for SRC-activated STAT-3 in 14,15-EET-induced VEGF expression and angiogenesis. Blood 2008; 111:5581-91. [PMID: 18408167 DOI: 10.1182/blood-2007-11-126680] [Citation(s) in RCA: 104] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
To understand the molecular mechanisms underlying 14,15-epoxyeicosatrienoic acid (14,15-EET)-induced angiogenesis, here we have studied the role of signal transducer and activator of transcription-3 (STAT-3). 14,15-EET stimulated the tyrosine phosphorylation of STAT-3 and its translocation from the cytoplasm to the nucleus in human dermal microvascular endothelial cells (HDMVECs). Adenovirus-mediated delivery of dominant negative STAT-3 substantially inhibited 14,15-EET-induced HDMVEC migration, and tube formation and Matrigel plug angiogenesis. 14,15-EET activated Src, as measured by its tyrosine phosphorylation and blockade of its activation by adenovirus-mediated expression of its dominant negative mutant, significantly attenuated 14,15-EET-induced STAT-3 phosphorylation in HDMVECs and the migration and tube formation of these cells and Matrigel plug angiogenesis. 14,15-EET induced the expression of vascular endothelial cell growth factor (VEGF) in a time- and Src-STAT-3-dependent manner in HDMVECs. Transfac analysis of VEGF promoter revealed the presence of STAT-binding elements and 14,15-EET induced STAT-3 binding to this promoter in vivo, and this interaction was inhibited by suppression of Src-STAT-3 signaling. Neutralizing anti-VEGF antibodies completely blocked 14,15-EET-induced HDMVEC migration and tube formation and Matrigel plug angiogenesis. These results reveal that Src-dependent STAT-3-mediated VEGF expression is a major mechanism of 14,15-EET-induced angiogenesis.
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Hexachlorobenzene triggers AhR translocation to the nucleus, c-Src activation and EGFR transactivation in rat liver. Toxicol Lett 2008; 177:116-22. [PMID: 18295415 DOI: 10.1016/j.toxlet.2008.01.003] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2007] [Revised: 01/03/2008] [Accepted: 01/03/2008] [Indexed: 11/20/2022]
Abstract
Hexachlorobenzene (HCB) is a widespread environmental pollutant. It has some properties that are typical for dioxin-like compounds that act mainly through the aryl hydrocarbon receptor (AhR) protein. Upon dioxin binding, the AhR translocates to the nucleus and modulates gene expression. At the same time, c-Src kinase frees from the AhR complex and thereby activates its own kinase activity, which acts as a trigger for the growth factor receptor signal transduction pathway. HCB is a weak agonist of the AhR, and the evidence that HCB toxicity is mediated via the AhR complex is limited and inconclusive. In the present study, female Wistar rats were administered HCB (1, 10 and 100mg/kg) for 30 days. Liver cytosolic AhR was translocated to the nucleus. The activity of liver microsomal c-Src increased at all assayed doses. HCB induced the association of the EGFR with c-Src and increased the phosphorylation of EGFR at tyrosine 845 (Tyr845), a known c-Src phosphorylation site. c-Src from WB-F344 cells treated with HCB exhibited increased protein levels and c-Src-pTyr416 phosphorylation than the control cells. Again HCB induced EGFR phosphorylation at Tyr845. Such an effect of HCB could not be detected when c-Src activity was blocked by PP2. All together, our data demonstrates that HCB may induce EGFR transactivation through an c-Src-dependent pathway.
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Lu Y, Li X, Liang K, Luwor R, Siddik ZH, Mills GB, Mendelsohn J, Fan Z. Epidermal growth factor receptor (EGFR) ubiquitination as a mechanism of acquired resistance escaping treatment by the anti-EGFR monoclonal antibody cetuximab. Cancer Res 2007; 67:8240-7. [PMID: 17804738 DOI: 10.1158/0008-5472.can-07-0589] [Citation(s) in RCA: 126] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Cetuximab is an epidermal growth factor receptor (EGFR)-blocking antibody that has been approved for treatment of patients with metastatic colorectal cancer. In this study, we investigated biochemical changes in signaling pathways of a cetuximab-resistant subline of DiFi colorectal cancer cells (DiFi5) that was developed by exposing the parental sensitive cells to subeffective doses of cetuximab over an extended period of time. Compared with parental DiFi cells that express high levels of EGFR and in which cetuximab induces apoptosis, the cetuximab-resistant DiFi5 cells showed markedly lower protein levels of EGFR, an increased association of EGFR with Cbl, and an increased ubiquitination of EGFR. DiFi5 cells also had a markedly higher level of Src-Y416 phosphorylation both at baseline and on EGF stimulation. Although EGFR levels were low, DiFi5 cells responded to EGF stimulation with robust phosphorylation of EGFR on Y845 and strong phosphorylation of Akt and extracellular signal-regulated kinase, comparable to those of parental cells. Most importantly, inhibition of Src kinase activity with PP2 reversed the resistance of DiFi5 cells to cetuximab-induced apoptosis without affecting the levels of EGFR in the cells. Our results indicate that colorectal cancer cells may develop acquired resistance to cetuximab via altering EGFR levels through promotion of EGFR ubiquitination and degradation and using Src kinase-mediated cell signaling to bypass their dependency on EGFR for cell growth and survival.
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Affiliation(s)
- Yang Lu
- Department of Experimental Therapeutics, The University of Texas M D Anderson Cancer Center, Houston, TX 77030, USA
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Yang S, Park K, Turkson J, Arteaga CL. Ligand-independent phosphorylation of Y869 (Y845) links mutant EGFR signaling to stat-mediated gene expression. Exp Cell Res 2007; 314:413-9. [PMID: 17927978 DOI: 10.1016/j.yexcr.2007.09.002] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2007] [Revised: 09/05/2007] [Accepted: 09/05/2007] [Indexed: 12/31/2022]
Abstract
Activating mutants of EGFR have been identified in a subset of non-small-cell lung cancers. To investigate mutant-driven signaling, we focused on Y869, a residue in the same activation loop where the L858R and L861Q mutations are located. We observed ligand-independent phosphorylation of Y869 in 32D cells EGFR(L858R) and EGFR(L861Q). The EGFR tyrosine kinase inhibitor (TKI) erlotinib inhibited Y869 P-EGFR in intact cells as well as in a cell-free kinase reaction. Expression of kinase domain of EGFR(L858R) and EGFR(L861Q) exhibited auto-phosphorylation of Y869; this was inhibited by EGFR TKIs but not by Src kinase inhibitor. P-Y859 of EGFR-mediated downstream component, STAT5, was also analyzed. Y694 P-STAT5 was eliminated by erlotinib treatment. Analysis of immune-complexes showed constitutive association of mutant EGFRs with STAT5 and Src which was unaffected by erlotinib or PP1. On the other hand, 32D-EGFR(WT) exhibited constitutive STAT5 phosphorylation and association of EGFR with JAK2. In these cells, a JAK2 inhibitor abrogated P-STAT5 whereas mutant EGFRs did not associate with JAK2. Expression of c-myc was regulated by EGFR/STAT5 signaling in cells expressing EGFR(L858R) and EGFR(L861Q). Our results suggest that ligand-independent and Src activity-independent phosphorylation of Y869 in mutant EGFR regulates STAT5 activation and c-myc expression.
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Affiliation(s)
- Seungchan Yang
- Department of Medicine, Vanderbilt-Ingram Comprehensive Cancer Center, Vanderbilt University School of Medicine, Nashville, TN, USA
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Na II, Rho JK, Choi YJ, Kim CH, Park JH, Koh JS, Ryoo BY, Yang SH, Lee JC. The survival outcomes of patients with resected non-small cell lung cancer differ according to EGFR mutations and the P21 expression. Lung Cancer 2007; 57:96-102. [PMID: 17337084 DOI: 10.1016/j.lungcan.2007.01.027] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2006] [Revised: 12/07/2006] [Accepted: 01/30/2007] [Indexed: 10/23/2022]
Abstract
The aims of this study were to evaluate the prognostic implications of patients with epidermal growth factor receptor (EGFR) mutations and a p21 expression, and to determine their associations in resected non-small cell lung cancer (NSCLC) patients. We sequenced exons 18-21 of the EGFR tyrosine kinase domain by performing mutation analysis of tissues from patients that suffered with NSCLC and who also had undergone surgical resection. The expressions of p21 and p53 were analyzed using immunohistochemistry. We detected EGFR mutations in 24 of 97 patients (25%). EGFR mutations were more frequent in the people who had never smoked than in the smokers (33% versus 14%, respectively; P=.028). The presence of EGFR mutations had no effect on survival. The expression of p21 in the patients with wild-type EGFR tended to be associated with better survival. However, the expression of p21 in the patients with EGFR mutations was associated with poor overall survival (P=.006). The five-year survival rates were 17% for the patients with EGFR mutations and p21 positivity (Group I), 44% for the patients with wild type EGFR (Group II), and 75% for the patients with EGFR mutation and no p21 positivity (Group III) (P=.036). Multivariate analysis that was corrected for age, gender and cancer stage revealed different overall survival outcomes according to the three groups (P=.004). There was no significant correlation between the expressions of p21 and p53. Survival outcomes in the patients with resected NSCLC may be correlated with the presence of a p21 expression and EGFR mutations.
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Affiliation(s)
- Im Il Na
- Department of Internal Medicine, Korea Cancer Center Hospital, Korea Institute of Radiological & Medical Sciences, Nowon-gu, Seoul, South Korea
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Valkova C, Maerz S, Imhof D, Liebmann C. Protein kinase Cepsilon may act as EGF-inducible scaffold protein for phospholipase Cgamma1. Cell Signal 2007; 19:1830-43. [PMID: 17561374 DOI: 10.1016/j.cellsig.2007.04.004] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2007] [Accepted: 04/07/2007] [Indexed: 11/30/2022]
Abstract
Phospholipase Cgamma1 (PLCgamma1) represents a major downstream signalling component of the epidermal growth factor (EGF) receptor (EGFR) and is activated by tyrosine phosphorylation. Here we show for the first time that cellular knockdown of protein kinase Cepsilon (PKCepsilon) leads to decreased activation of PLCgamma1 by EGF and that EGF induces tyrosine phosphorylation of PKCepsilon as well as association of PKCepsilon with both EGFR and PLCgamma1. Using several mutants, co-immunoprecipitation and phosphopeptide-based pull-down experiments we found that in dependency on c-Src and EGF-stimulation PKCepsilon may bind to the c-Src-specific phosphorylation site pY845-EGFR. Furthermore, we identified a single tyrosine residue, PKCepsilon-Y573, within a consensus binding sequence of the C-terminal SH2 domain of PLCgamma1 which is critical for both tyrosine phosphorylation of PKCepsilon and its association with PLCgamma1. Thus, in particular cells and independent of the kinase activity PKCepsilon may form a signalling module with EGFR and PLCgamma1. Thereby the tyrosine phosphorylation of PLCgamma1 via the EGFR may be facilitated. This is a novel function of PKCepsilon upstream of PLCgamma1 and a novel paradigm for the EGF-induced formation of multi-protein complexes.
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Affiliation(s)
- Christina Valkova
- Institut für Biochemie und Biophysik, Biologisch-Pharmazeutische Fakultät, Friedrich-Schiller-Universität Jena, Philosophenweg 12, D-07743 Jena, Germany
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Burova E, Vassilenko K, Dorosh V, Gonchar I, Nikolsky N. Interferon gamma-dependent transactivation of epidermal growth factor receptor. FEBS Lett 2007; 581:1475-80. [PMID: 17362940 DOI: 10.1016/j.febslet.2007.03.002] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2007] [Accepted: 03/01/2007] [Indexed: 11/16/2022]
Abstract
The present report provides evidence that, in A431 cells, interferon gamma (IFNgamma) induces the rapid (within 5 min), and reversible, tyrosine phosphorylation of the epidermal growth factor receptor (EGFR). IFNgamma-induced EGFR transactivation requires EGFR kinase activity, as well as activity of the Src-family tyrosine kinases and JAK2. Here, we show that IFNgamma-induced STAT1 activation in A431 and HeLa cells partially depends on the kinase activity of both EGFR and Src. Furthermore, in these cells, EGFR kinase activity is essential for IFNgamma-induced ERK1,2 activation. This study is the first to demonstrate that EGFR is implicated in IFNgamma-dependent signaling pathways.
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Affiliation(s)
- Elena Burova
- Department of Intracellular Signaling and Transport, Institute of Cytology of Russian Academy of Sciences, St.-Petersburg 194064, Russia.
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45
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Moiseeva EP, Heukers R, Manson MM. EGFR and Src are involved in indole-3-carbinol-induced death and cell cycle arrest of human breast cancer cells. Carcinogenesis 2007; 28:435-45. [PMID: 16956907 DOI: 10.1093/carcin/bgl171] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
Indole-3-carbinol (I3C), a dietary chemopreventive compound, induced marked reduction in epidermal growth factor receptor (EGFR) prior to cell death in cells representing three breast cancer subtypes. Signalling pathways, linking these events were investigated in detail. I3C modulated tyrosine phosphorylation from 30 min in four cell lines. In MDA-MB-468 and HBL100 cells, it induced Src activation after 5 h. In MDA-MB-468 cells, I3C induced signalling between 4.5 and 7 h, which involved sequential activation of Src, EGFR, STAT-1 and STAT-3, followed by EGFR degradation. It also induced physical association between activated Src and EGFR. In MCF7 and MDA-MB-231 cells, I3C modulated expression of cell cycle-related proteins, p21Cip1, p27Kip1, cyclin E, cyclin D1 and CDK6, with upregulation of p21Cip1 and cyclin E being dependent on Src. Inhibition of EGFR by specific inhibitors PD153035 or ZD1839 increased susceptibility to I3C-induced apoptosis of MCF7, MDA-MB-468 and MDA-MB-231 cells. Inhibition of Src sensitized MDA-MB-468 and MDA-MB-231 cells to I3C, whereas overexpression of c-Src increased resistance to I3C in MDA-MB-468 and HBL100 cells. Modulation of Src in MDA-MB-468 cells influenced the basal level of EGFR expression and cell viability; the latter being positively correlated with EGFR activation levels. Therefore, EGFR and Src activities are essential for I3C-induced cell cycle arrest and death; however, I3C-induced pathways depend on specific features of breast cancer cells. The cancer types, which rely on 'EGFR addiction' or Src deregulation, are likely to be susceptible to I3C.
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Affiliation(s)
- Elena P Moiseeva
- Cancer Biomarkers and Prevention Group, Department of Biochemistry, University of Leicester, Leicester LE1 7RH, UK.
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Yamamoto N, Mammadova G, Song RXD, Fukami Y, Sato KI. Tyrosine phosphorylation of p145met mediated by EGFR and Src is required for serum-independent survival of human bladder carcinoma cells. J Cell Sci 2006; 119:4623-33. [PMID: 17062641 DOI: 10.1242/jcs.03236] [Citation(s) in RCA: 52] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Here we address the molecular mechanism of serum-independent survival and growth of human bladder carcinoma cell line 5637. Serum starvation promoted tyrosine phosphorylation of a 145-kDa protein and activation of the tyrosine kinase Src and the receptor for epidermal growth factor (EGFR) over a slow time course (>8 hours). The phosphorylated 145-kDa protein was identified as the beta-subunit of c-Met/hepatocyte growth factor (HGF) receptor, p145(met), in which tyrosine residues 1003, 1234, and 1235 were phosphorylated. Inhibitors of Src (PP2, SU6656) or EGFR (AG99), but not p145(met) (K252a), effectively blocked tyrosine phosphorylation of p145(met) and promoted cell death accompanied by activation of caspase-like proteases. Conditioned medium from the serum-starved 5637 cells or purified EGF readily promoted the activation of Src and EGFR, and tyrosine phosphorylation of p145(met) in normally grown 5637 cells, suggesting that autocrine signaling of EGFR ligands is responsible for signal transduction events in serum-starved cells. Consistent with this idea, a monoclonal antibody against EGFR that would interfere with the ligand binding to EGFR blocked tyrosine phosphorylation events and promoted the caspase activation and cell death in serum-free conditions. Such apoptotic cell death was also induced by pretreatment of cells with a high concentration of HGF that downregulated endogenous p145(met). Nevertheless, Cu2+ ions, competitive inhibitors for HGF-binding to p145(met), did not show any effect on cellular functions in serum-free conditions. These results suggest that the serum-independent growth of 5637 cells involves the transmembrane signaling cascade via EGFR ligand(s) (but not HGF), EGFR, Src and p145(met).
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Affiliation(s)
- Natsumi Yamamoto
- Graduate School of Science and Technology, Kobe University, Nada, Kobe, Japan
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Yacoub A, Hawkins W, Hanna D, Young H, Park MA, Grant M, Roberts JD, Curiel DT, Fisher PB, Valerie K, Grant S, Hagan MP, Dent P. Human chorionic gonadotropin modulates prostate cancer cell survival after irradiation or HMG CoA reductase inhibitor treatment. Mol Pharmacol 2006; 71:259-75. [PMID: 17050804 DOI: 10.1124/mol.106.031153] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The impact of human chorionic gonadotropin (hCG) on prostate carcinoma viability was investigated. Treatment of LNCaP and PC-3 cells with hCG modestly reduced cell viability within 96 h. Treatment of cells with hCG followed by exposure to ionizing radiation enhanced radiosensitivity. Exposure of LNCaP cells to hCG promoted activation of epidermal growth factor receptor (ERBB1) via a Galpha(i)-, mitogen-activated protein kinase kinase (MEK)1/2-, and metalloprotease-dependent paracrine mechanism, effects that were further enhanced after radiation exposure, and that were causal in prolonged intense activation of poly(ADP-ribose) polymerase (PARP). Inhibition of ERBB1, MEK1, or PARP1 function suppressed the radiosensitizing properties of hCG. Radiosensitization was also, in part, dependent upon c-Jun NH2-terminal kinase 1/2 signaling. PARP1-dependent radiosensitization was suppressed by a pan-caspase inhibitor and by knockdown of apoptosis-inducing factor expression. Inhibition of phosphatidylinositol 3-kinase, expression of dominant-negative AKT, or treatment with the HMG CoA reductase inhibitor lovastatin suppressed AKT phosphorylation and enhanced the cytotoxic effects of hCG. The enhancing effect of lovastatin was reproduced by incubation with a geranylgeranyl transferase inhibitor and blocked by coexposure to geranylgeranyl pyrophosphate. Treatment with hCG and lovastatin decreased expression of BCL-(XL) and XIAP, and increased expression of IkappaB. The cytotoxic effects of hCG were enhanced by expression of dominant-negative IkappaB, and they were abolished by coexpression of activated AKT. Expression of activated AKT maintained BCL-(XL) levels in cells expressing dominant-negative IkappaB. The promotion of hCG lethality by lovastatin was abolished by overexpression of BCL-(XL), and was dependent upon activation of caspase-9. Thus, hCG, in combination with radiation and lovastatin, may represent a novel approach to kill prostate cancer cells.
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Affiliation(s)
- Adly Yacoub
- Department of Biochemistry, 401 College St., Massey Cancer Center, Room 2-108, Box 980035, Virginia Commonwealth University, Richmond VA 23298-0035, USA
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Zhao Y, He D, Saatian B, Watkins T, Spannhake EW, Pyne NJ, Natarajan V. Regulation of lysophosphatidic acid-induced epidermal growth factor receptor transactivation and interleukin-8 secretion in human bronchial epithelial cells by protein kinase Cdelta, Lyn kinase, and matrix metalloproteinases. J Biol Chem 2006; 281:19501-11. [PMID: 16687414 PMCID: PMC2760938 DOI: 10.1074/jbc.m511224200] [Citation(s) in RCA: 89] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
We have demonstrated earlier that lysophosphatidic acid (LPA)-induced interleukin-8 (IL-8) secretion is regulated by protein kinase Cdelta (PKCdelta)-dependent NF-kappaB activation in human bronchial epithelial cells (HBEpCs). Here we provide evidence for signaling pathways that regulate LPA-mediated transactivation of epidermal growth factor receptor (EGFR) and the role of cross-talk between G-protein-coupled receptors and receptor-tyrosine kinases in IL-8 secretion in HBEpCs. Treatment of HBEpCs with LPA stimulated tyrosine phosphorylation of EGFR, which was attenuated by matrix metalloproteinase (MMP) inhibitor (GM6001), heparin binding (HB)-EGF inhibitor (CRM 197), and HB-EGF neutralizing antibody. Overexpression of dominant negative PKCdelta or pretreatment with a PKCdelta inhibitor (rottlerin) or Src kinase family inhibitor (PP2) partially blocked LPA-induced MMP activation, proHB-EGF shedding, and EGFR tyrosine phosphorylation. Down-regulation of Lyn kinase, but not Src kinase, by specific small interfering RNA mitigated LPA-induced MMP activation, proHB-EGF shedding, and EGFR phosphorylation. In addition, overexpression of dominant negative PKCdelta blocked LPA-induced phosphorylation and translocation of Lyn kinase to the plasma membrane. Furthermore, down-regulation of EGFR by EGFR small interfering RNA or pretreatment of cells with EGFR inhibitors AG1478 and PD158780 almost completely blocked LPA-dependent EGFR phosphorylation and partially attenuated IL-8 secretion, respectively. These results demonstrate that LPA-induced IL-8 secretion is partly dependent on EGFR transactivation regulated by PKCdelta-dependent activation of Lyn kinase and MMPs and proHB-EGF shedding, suggesting a novel mechanism of cross-talk and interaction between G-protein-coupled receptors and receptor-tyrosine kinases in HBEpCs.
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Affiliation(s)
- Yutong Zhao
- Section of Pulmonary and Critical Care Medicine, Department of Medicine, University of Chicago, Chicago, Illinois 60637, USA
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Nakasato M, Shirakura Y, Ooga M, Iwatsuki M, Ito M, Kageyama SI, Sakai S, Nagata M, Aoki F. Involvement of the STAT5 signaling pathway in the regulation of mouse preimplantation development. Biol Reprod 2006; 75:508-17. [PMID: 16775227 DOI: 10.1095/biolreprod.105.047860] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022] Open
Abstract
The signal transducer and activator of transcription 5 (STAT5) is an essential factor in the signal transduction pathways for a number of cytokines that regulate the growth and differentiation of mammalian cells. In this study, we investigated the STAT5 signaling pathway in mouse embryos, to elucidate the mechanism of cytokine signal transduction that regulates preimplantation development. The results of the RT-PCR analysis showed that both STAT5A and B were expressed throughout preimplantation development. Immunocytochemistry revealed that the STAT5A/B proteins were located in the nucleus from the early 1-cell stage to the blastocyst stage. STAT5 activation appeared to be regulated by Janus kinases (JAKs) and SRC family kinases (SFKs), since inhibitors of these kinases inhibited the localization of STAT5 proteins to the nucleus. The JAK inhibitor Ag490 reduced both the developmental rate of the embryos and the expression levels of the downstream genes of the JAK-STAT5 signaling pathway. These findings suggest that STAT5 proteins function in preimplantation development by mediating the signals from cytokines.
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Affiliation(s)
- Makoto Nakasato
- Department of Integrated Biosciences, Graduate School of Frontier Sciences, University of Tokyo, Chiba 277-8562, Japan
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50
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Abstract
Multifocal angiostatic therapy (MAT) is a strategy that seeks to impede cancer-induced angiogenesis by addressing multiple targets that regulate the angiogenic capacity of a cancer and/or the angiogenic responsiveness of endothelial cells, using measures that are preferentially, but not exclusively, nutraceutical. A prototype of such a regimen has been proposed previously, composed of green tea polyphenols, fish oil, selenium, and high-dose glycine, complementing a low-fat vegan diet, exercise training, and the copper-sequestering drug tetrathiomolybdate (TM). A review of more recent evidence suggests additional agents that could appropriately be included in this regimen and clarifies to some extent the mechanisms of action of its constituents. Diindolylmethane, a widely available crucifera-derived nutraceutical, has inhibited cancer growth in several mouse xenograft models; this effect may be largely attributable to an angiostatic action, as concentrations as low as 5 to 10 muM inhibit proliferation, migration, and tube-forming capacity of human endothelial cells in vitro, and a parenteral dose of 5 mg/kg markedly impairs matrigel angiogenesis in mice. Silymarin/silbinin, which has slowed the growth of human xenografts in a number of studies, suppresses the proliferation, migration, and tube-forming capacity of endothelial cells and inhibits vascular endothelial growth factor (VEGF) secretion by a range of human cancer cell lines, in concentrations that should be clinically feasible. The angiostatic activity of orally administered green tea now appears likely to reflect inhibition of the kinase activity of VEGFR-2. Glycine's angiostatic activity may be attributable to a hyperpolarizing effect on endothelial cells that decreases the activity of NADPH oxidase, now known to promote tyrosine kinase signaling in endothelial cells. The ability of TM to suppress cancer cell production of a range of angiogenic factors results at least in part from a down regulation of NF-kappaB activation. Dual-purpose molecular targets, whose inhibition could be expected to decrease the aggressiveness and chemoresistance of cancer cells while simultaneously impeding angiogenesis, include NF-kappaB, cox-2, c-Src, Stat3, and hsp90; drugs that can address these targets are now in development, and salicylates are notable for the fact that they can simultaneously inhibit NF-kappaB and cox-2. The potential complementary of the components of MAT should be assessed in nude mouse xenograft models.
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Affiliation(s)
- Mark F McCarty
- Block Center for Integrative Cancer Care, Evanston, Illinois 60201, USA.
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