1
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Bagchi A, Stayrook SE, Xenaki KT, Starbird CA, Doulkeridou S, El Khoulati R, Roovers RC, Schmitz KR, van Bergen En Henegouwen PMP, Ferguson KM. Structural insights into the role and targeting of EGFRvIII. Structure 2024:S0969-2126(24)00195-3. [PMID: 38908376 DOI: 10.1016/j.str.2024.05.018] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2023] [Revised: 04/06/2024] [Accepted: 05/28/2024] [Indexed: 06/24/2024]
Abstract
The epidermal growth factor receptor (EGFR) is a well-known oncogenic driver in lung and other cancers. In glioblastoma multiforme (GBM), the EGFR deletion variant III (EGFRvIII) is frequently found alongside EGFR amplification. Agents targeting the EGFR axis have shown limited clinical benefits in GBM and the role of EGFRvIII in GBM is poorly understood. To shed light on the role of EGFRvIII and its potential as a therapeutic target, we determined X-ray crystal structures of a monomeric EGFRvIII extracellular region (ECR). The EGFRvIII ECR resembles the unliganded conformation of EGFR, including the orientation of the C-terminal region of domain II. Domain II is mostly disordered, but the ECR structure is compact. We selected a nanobody with preferential binding to EGFRvIII relative to EGFR and structurally defined an epitope on domain IV that is occluded in the unliganded intact EGFR. These findings suggest new avenues for EGFRvIII targeting in GBM.
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Affiliation(s)
- Atrish Bagchi
- Graduate Group in Biochemistry and Molecular Biophysics, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Steven E Stayrook
- Department of Pharmacology, Yale University School of Medicine, New Haven, CT 06520, USA; Yale Cancer Biology Institute, Yale University West Campus, West Haven, CT 06516, USA
| | - Katerina T Xenaki
- Division of Cell Biology, Neurobiology and Biophysics, Department of Biology, Science Faculty, Utrecht University, Utrecht 3584CH, the Netherlands
| | - Chrystal A Starbird
- Department of Pharmacology, Yale University School of Medicine, New Haven, CT 06520, USA; Yale Cancer Biology Institute, Yale University West Campus, West Haven, CT 06516, USA
| | - Sofia Doulkeridou
- Division of Cell Biology, Neurobiology and Biophysics, Department of Biology, Science Faculty, Utrecht University, Utrecht 3584CH, the Netherlands
| | - Rachid El Khoulati
- Division of Cell Biology, Neurobiology and Biophysics, Department of Biology, Science Faculty, Utrecht University, Utrecht 3584CH, the Netherlands
| | - Rob C Roovers
- Division of Cell Biology, Neurobiology and Biophysics, Department of Biology, Science Faculty, Utrecht University, Utrecht 3584CH, the Netherlands
| | - Karl R Schmitz
- Department of Biological Sciences, University of Delaware, Newark, DE, USA
| | - Paul M P van Bergen En Henegouwen
- Division of Cell Biology, Neurobiology and Biophysics, Department of Biology, Science Faculty, Utrecht University, Utrecht 3584CH, the Netherlands
| | - Kathryn M Ferguson
- Department of Pharmacology, Yale University School of Medicine, New Haven, CT 06520, USA; Yale Cancer Biology Institute, Yale University West Campus, West Haven, CT 06516, USA.
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2
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Yan T, Boatner LM, Cui L, Tontonoz PJ, Backus KM. Defining the Cell Surface Cysteinome Using Two-Step Enrichment Proteomics. JACS AU 2023; 3:3506-3523. [PMID: 38155636 PMCID: PMC10751780 DOI: 10.1021/jacsau.3c00707] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/13/2023] [Revised: 11/17/2023] [Accepted: 11/20/2023] [Indexed: 12/30/2023]
Abstract
The plasma membrane proteome is a rich resource of functionally important and therapeutically relevant protein targets. Distinguished by high hydrophobicity, heavy glycosylation, disulfide-rich sequences, and low overall abundance, the cell surface proteome remains undersampled in established proteomic pipelines, including our own cysteine chemoproteomics platforms. Here, we paired cell surface glycoprotein capture with cysteine chemoproteomics to establish a two-stage enrichment method that enables chemoproteomic profiling of cell Surface Cysteinome. Our "Cys-Surf" platform captures >2,800 total membrane protein cysteines in 1,046 proteins, including 1,907 residues not previously captured by bulk proteomic analysis. By pairing Cys-Surf with an isotopic chemoproteomic readout, we uncovered 821 total ligandable cysteines, including known and novel sites. Cys-Surf also robustly delineates redox-sensitive cysteines, including cysteines prone to activation-dependent changes to cysteine oxidation state and residues sensitive to addition of exogenous reductants. Exemplifying the capacity of Cys-Surf to delineate functionally important cysteines, we identified a redox sensitive cysteine in the low-density lipoprotein receptor (LDLR) that impacts both the protein localization and uptake of low-density lipoprotein (LDL) particles. Taken together, the Cys-Surf platform, distinguished by its two-stage enrichment paradigm, represents a tailored approach to delineate the functional and therapeutic potential of the plasma membrane cysteinome.
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Affiliation(s)
- Tianyang Yan
- Department
of Biological Chemistry, David Geffen School of Medicine, UCLA, Los Angeles, California 90095, United States
- Department
of Chemistry and Biochemistry, UCLA, Los Angeles, California 90095, United States
| | - Lisa M. Boatner
- Department
of Biological Chemistry, David Geffen School of Medicine, UCLA, Los Angeles, California 90095, United States
- Department
of Chemistry and Biochemistry, UCLA, Los Angeles, California 90095, United States
| | - Liujuan Cui
- Department
of Biological Chemistry, David Geffen School of Medicine, UCLA, Los Angeles, California 90095, United States
- Department
of Pathology and Laboratory Medicine, David Geffen School of Medicine, UCLA, Los Angeles, Los Angeles, California 90095, United States
| | - Peter J. Tontonoz
- Department
of Biological Chemistry, David Geffen School of Medicine, UCLA, Los Angeles, California 90095, United States
- Department
of Pathology and Laboratory Medicine, David Geffen School of Medicine, UCLA, Los Angeles, Los Angeles, California 90095, United States
| | - Keriann M. Backus
- Department
of Biological Chemistry, David Geffen School of Medicine, UCLA, Los Angeles, California 90095, United States
- Department
of Chemistry and Biochemistry, UCLA, Los Angeles, California 90095, United States
- DOE
Institute for Genomics and Proteomics, UCLA, Los Angeles, California 90095, United States
- Jonsson
Comprehensive Cancer Center, UCLA, Los Angeles, California 90095, United States
- Eli
and Edythe
Broad Center of Regenerative Medicine and Stem Cell Research, UCLA, Los Angeles, California 90095, United States
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3
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Dewdney B, Jenkins MR, Best SA, Freytag S, Prasad K, Holst J, Endersby R, Johns TG. From signalling pathways to targeted therapies: unravelling glioblastoma's secrets and harnessing two decades of progress. Signal Transduct Target Ther 2023; 8:400. [PMID: 37857607 PMCID: PMC10587102 DOI: 10.1038/s41392-023-01637-8] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2022] [Revised: 08/29/2023] [Accepted: 09/07/2023] [Indexed: 10/21/2023] Open
Abstract
Glioblastoma, a rare, and highly lethal form of brain cancer, poses significant challenges in terms of therapeutic resistance, and poor survival rates for both adult and paediatric patients alike. Despite advancements in brain cancer research driven by a technological revolution, translating our understanding of glioblastoma pathogenesis into improved clinical outcomes remains a critical unmet need. This review emphasises the intricate role of receptor tyrosine kinase signalling pathways, epigenetic mechanisms, and metabolic functions in glioblastoma tumourigenesis and therapeutic resistance. We also discuss the extensive efforts over the past two decades that have explored targeted therapies against these pathways. Emerging therapeutic approaches, such as antibody-toxin conjugates or CAR T cell therapies, offer potential by specifically targeting proteins on the glioblastoma cell surface. Combination strategies incorporating protein-targeted therapy and immune-based therapies demonstrate great promise for future clinical research. Moreover, gaining insights into the role of cell-of-origin in glioblastoma treatment response holds the potential to advance precision medicine approaches. Addressing these challenges is crucial to improving outcomes for glioblastoma patients and moving towards more effective precision therapies.
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Affiliation(s)
- Brittany Dewdney
- Cancer Centre, Telethon Kids Institute, Nedlands, WA, 6009, Australia.
- Centre For Child Health Research, University of Western Australia, Perth, WA, 6009, Australia.
| | - Misty R Jenkins
- Immunology Division, The Walter and Eliza Hall Institute of Medical Research, Melbourne, 3052, Australia
- Department of Medical Biology, University of Melbourne, Melbourne, 3010, Australia
| | - Sarah A Best
- Department of Medical Biology, University of Melbourne, Melbourne, 3010, Australia
- Personalised Oncology Division, The Walter and Eliza Hall Institute of Medical Research, Melbourne, 3052, Australia
| | - Saskia Freytag
- Department of Medical Biology, University of Melbourne, Melbourne, 3010, Australia
- Personalised Oncology Division, The Walter and Eliza Hall Institute of Medical Research, Melbourne, 3052, Australia
| | - Krishneel Prasad
- Immunology Division, The Walter and Eliza Hall Institute of Medical Research, Melbourne, 3052, Australia
- Department of Medical Biology, University of Melbourne, Melbourne, 3010, Australia
| | - Jeff Holst
- School of Biomedical Sciences, University of New South Wales, Sydney, 2052, Australia
| | - Raelene Endersby
- Cancer Centre, Telethon Kids Institute, Nedlands, WA, 6009, Australia
- Centre For Child Health Research, University of Western Australia, Perth, WA, 6009, Australia
| | - Terrance G Johns
- Cancer Centre, Telethon Kids Institute, Nedlands, WA, 6009, Australia
- Centre For Child Health Research, University of Western Australia, Perth, WA, 6009, Australia
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4
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Yan T, Boatner LM, Cui L, Tontonoz P, Backus KM. Defining the Cell Surface Cysteinome using Two-step Enrichment Proteomics. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.10.17.562832. [PMID: 37904933 PMCID: PMC10614875 DOI: 10.1101/2023.10.17.562832] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/01/2023]
Abstract
The plasma membrane proteome is a rich resource of functional and therapeutically relevant protein targets. Distinguished by high hydrophobicity, heavy glycosylation, disulfide-rich sequences, and low overall abundance, the cell surface proteome remains undersampled in established proteomic pipelines, including our own cysteine chemoproteomics platforms. Here we paired cell surface glycoprotein capture with cysteine chemoproteomics to establish a two-stage enrichment method that enables chemoproteomic profiling of cell Surface Cysteinome. Our "Cys-Surf" platform captures >2,800 total membrane protein cysteines in 1,046 proteins, including 1,907 residues not previously captured by bulk proteomic analysis. By pairing Cys-Surf with an isotopic chemoproteomic readout, we uncovered 821 total ligandable cysteines, including known and novel sites. Cys-Surf also robustly delineates redox-sensitive cysteines, including cysteines prone to activation-dependent changes to cysteine oxidation state and residues sensitive to addition of exogenous reductants. Exemplifying the capacity of Cys-Surf to delineate functionally important cysteines, we identified a redox sensitive cysteine in the low-density lipoprotein receptor (LDLR) that impacts both the protein localization and uptake of LDL particles. Taken together, the Cys-Surf platform, distinguished by its two-stage enrichment paradigm, represents a tailored approach to delineate the functional and therapeutic potential of the plasma membrane cysteinome.
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Affiliation(s)
- Tianyang Yan
- Department of Biological Chemistry, David Geffen School of Medicine, UCLA, Los Angeles, CA 90095 (USA)
- Department of Chemistry and Biochemistry, UCLA, Los Angeles, CA 90095 (USA)
| | - Lisa M. Boatner
- Department of Biological Chemistry, David Geffen School of Medicine, UCLA, Los Angeles, CA 90095 (USA)
- Department of Chemistry and Biochemistry, UCLA, Los Angeles, CA 90095 (USA)
| | - Liujuan Cui
- Department of Biological Chemistry, David Geffen School of Medicine, UCLA, Los Angeles, CA 90095 (USA)
- Department of Pathology and Laboratory Medicine, David Geffen School of Medicine, UCLA, Los Angeles; Los Angeles, CA 90095, USA
| | - Peter Tontonoz
- Department of Biological Chemistry, David Geffen School of Medicine, UCLA, Los Angeles, CA 90095 (USA)
- Department of Pathology and Laboratory Medicine, David Geffen School of Medicine, UCLA, Los Angeles; Los Angeles, CA 90095, USA
| | - Keriann M. Backus
- Department of Biological Chemistry, David Geffen School of Medicine, UCLA, Los Angeles, CA 90095 (USA)
- Department of Chemistry and Biochemistry, UCLA, Los Angeles, CA 90095 (USA)
- DOE Institute for Genomics and Proteomics, UCLA, Los Angeles, CA 90095 (USA)
- Jonsson Comprehensive Cancer Center, UCLA, Los Angeles, CA 90095 (USA)
- Eli and Edythe Broad Center of Regenerative Medicine and Stem Cell Research, UCLA, Los Angeles, CA 90095 (USA)
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5
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Li J, Wang S, He Q, Lin F, Tao C, Ding Y, Wang J, Zhao J, Wang W. High ECM2 Expression Predicts Poor Clinical Outcome and Promotes the Proliferation, Migration, and Invasiveness of Glioma. Brain Sci 2023; 13:851. [PMID: 37371331 DOI: 10.3390/brainsci13060851] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2023] [Revised: 05/04/2023] [Accepted: 05/22/2023] [Indexed: 06/29/2023] Open
Abstract
OBJECTIVE Glioma is the most prevalent and fatal intracranial malignant tumor. Extracellular matrix protein 2 (ECM2) has rarely been studied in gliomas. Therefore, we explored the role of ECM2 in lower-grade gliomas (LGGs). METHODS The RNA-seq and clinicopathology data were obtained from the TCGA database. The immunohistochemical (IHC) staining was used to verify the expression of ECM2. Functional enrichment analyses, immune-related analyses, drug sensitivity, and mutation profile analyses were further conducted. Cox regression and Kaplan-Meier curves were utilized for survival analyses, while four external datasets were used to validate the prognostic role of ECM2. Furthermore, qRT-PCR, CCK-8, wound healing, and transwell assays were performed to confirm the function of ECM2 in gliomas. RESULTS The study found a significant upregulation of ECM2 expression with increasing glioma grades and a significant association between ECM2 expression and tumor immune infiltration. Cox regression verified the prognostic role of ECM2 in LGG patients (HR = 1.656, 95%CI = 1.055-2.600, p = 0.028). High ECM2 expression was significantly associated with poor outcome (p < 0.001). Four external datasets validated its prognostic value. After the knockdown of ECM2, the functional experiments showed a significant decrease in proliferation, migration, and invasion in glioma cell lines. CONCLUSION The study suggested the potential of ECM2 as a novel immune-associated prognostic biomarker and therapeutic target for glioma patients.
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Affiliation(s)
- Junsheng Li
- Department of Neurosurgery, Beijing Tiantan Hospital, Capital Medical University, Beijing 100070, China
- China National Clinical Research Center for Neurological Diseases, Beijing 100070, China
- Center of Stroke, Beijing Institute for Brain Disorders, Beijing 100070, China
- Beijing Key Laboratory of Translational Medicine for Cerebrovascular Disease, Beijing 100070, China
- Beijing Translational Engineering Center for 3D Printer in Clinical Neuroscience, Beijing 100070, China
| | - Siyu Wang
- Department of Neurosurgery, Beijing Tiantan Hospital, Capital Medical University, Beijing 100070, China
| | - Qiheng He
- Department of Neurosurgery, Beijing Tiantan Hospital, Capital Medical University, Beijing 100070, China
- China National Clinical Research Center for Neurological Diseases, Beijing 100070, China
- Center of Stroke, Beijing Institute for Brain Disorders, Beijing 100070, China
- Beijing Key Laboratory of Translational Medicine for Cerebrovascular Disease, Beijing 100070, China
- Beijing Translational Engineering Center for 3D Printer in Clinical Neuroscience, Beijing 100070, China
| | - Fa Lin
- Department of Neurosurgery, Beijing Tiantan Hospital, Capital Medical University, Beijing 100070, China
- China National Clinical Research Center for Neurological Diseases, Beijing 100070, China
- Center of Stroke, Beijing Institute for Brain Disorders, Beijing 100070, China
- Beijing Key Laboratory of Translational Medicine for Cerebrovascular Disease, Beijing 100070, China
- Beijing Translational Engineering Center for 3D Printer in Clinical Neuroscience, Beijing 100070, China
| | - Chuming Tao
- Department of Neurosurgery, Second Affiliated Hospital of Soochow University, Suzhou 215004, China
| | - Yaowei Ding
- Department of Clinical Diagnosis, Laboratory of Beijing Tiantan Hospital, Capital Medical University, Beijing 100070, China
| | - Jia Wang
- Department of Neurosurgery, Beijing Tiantan Hospital, Capital Medical University, Beijing 100070, China
- China National Clinical Research Center for Neurological Diseases, Beijing 100070, China
- Center of Stroke, Beijing Institute for Brain Disorders, Beijing 100070, China
- Beijing Key Laboratory of Translational Medicine for Cerebrovascular Disease, Beijing 100070, China
- Beijing Translational Engineering Center for 3D Printer in Clinical Neuroscience, Beijing 100070, China
| | - Jizong Zhao
- Department of Neurosurgery, Beijing Tiantan Hospital, Capital Medical University, Beijing 100070, China
- China National Clinical Research Center for Neurological Diseases, Beijing 100070, China
- Center of Stroke, Beijing Institute for Brain Disorders, Beijing 100070, China
- Beijing Key Laboratory of Translational Medicine for Cerebrovascular Disease, Beijing 100070, China
- Beijing Translational Engineering Center for 3D Printer in Clinical Neuroscience, Beijing 100070, China
- Savaid Medical School, University of the Chinese Academy of Sciences, Beijing 101408, China
| | - Wen Wang
- Department of Neurosurgery, Beijing Tiantan Hospital, Capital Medical University, Beijing 100070, China
- China National Clinical Research Center for Neurological Diseases, Beijing 100070, China
- Center of Stroke, Beijing Institute for Brain Disorders, Beijing 100070, China
- Beijing Key Laboratory of Translational Medicine for Cerebrovascular Disease, Beijing 100070, China
- Beijing Translational Engineering Center for 3D Printer in Clinical Neuroscience, Beijing 100070, China
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6
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Increased EGFRvIII Epitope Accessibility after Tyrosine Kinase Inhibitor Treatment of Glioblastoma Cells Creates More Opportunities for Immunotherapy. Int J Mol Sci 2023; 24:ijms24054350. [PMID: 36901782 PMCID: PMC10001577 DOI: 10.3390/ijms24054350] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2022] [Revised: 02/10/2023] [Accepted: 02/17/2023] [Indexed: 02/24/2023] Open
Abstract
The number of glioblastoma (GB) cases is increasing every year, and the currently available therapies remain ineffective. A prospective antigen for GB therapy is EGFRvIII, an EGFR deletion mutant containing a unique epitope that is recognized by the L8A4 antibody used in CAR-T (chimeric antigen receptor T cell) therapy. In this study, we observed that the concomitant use of L8A4 with particular tyrosine kinase inhibitors (TKIs) does not impede the interaction between L8A4 and EGFRvIII; moreover, in this case, the stabilization of formed dimers results in increased epitope display. Unlike in wild-type EGFR, a free cysteine at position 16 (C16) is exposed in the extracellular structure of EGFRvIII monomers, leading to covalent dimer formation in the region of L8A4-EGFRvIII mutual interaction. Following in silico analysis of cysteines possibly involved in covalent homodimerization, we prepared constructs containing cysteine-serine substitutions of EGFRvIII in adjacent regions. We found that the extracellular part of EGFRvIII possesses plasticity in the formation of disulfide bridges within EGFRvIII monomers and dimers due to the engagement of cysteines other than C16. Our results suggest that the EGFRvIII-specific L8A4 antibody recognizes both EGFRvIII monomers and covalent dimers, regardless of the cysteine bridging structure. To summarize, immunotherapy based on the L8A4 antibody, including CAR-T combined with TKIs, can potentially increase the chances of success in anti-GB therapy.
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7
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Vaquero J, Pavy A, Gonzalez-Sanchez E, Meredith M, Arbelaiz A, Fouassier L. Genetic alterations shaping tumor response to anti-EGFR therapies. Drug Resist Updat 2022; 64:100863. [DOI: 10.1016/j.drup.2022.100863] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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8
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Greenall SA, McKenzie M, Seminova E, Dolezal O, Pearce L, Bentley J, Kuchibhotla M, Chen SC, McDonald KL, Kornblum HI, Endersby R, Adams TE, Johns TG. Most clinical anti-EGFR antibodies do not neutralize both wtEGFR and EGFRvIII activation in glioma. Neuro Oncol 2021; 21:1016-1027. [PMID: 31002307 DOI: 10.1093/neuonc/noz073] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
BACKGROUND Although epidermal growth factor receptor (EGFR) and its truncated, autoactive mutant EGFR variant (v)III are bona fide drivers of tumorigenesis in some gliomas, therapeutic antibodies developed to neutralize this axis have not improved patient survival in a limited number of trials. Previous studies using cells transduced to exogenously express EGFRvIII may have compromised mechanistic studies of anti-EGFR therapeutics. Therefore, we re-assessed the activity of clinical EGFR antibodies in patient-derived gliomaspheres that endogenously express EGFRvIII. METHODS The antitumor efficacy of antibodies was assessed using in vitro proliferation assays and intracranial orthografts. Receptor activation status, antibody engagement, oncogenic signaling, and mechanism of action after antibody treatment were analyzed by immunoprecipitation and western blotting. Tracking of antibody receptor complexes was conducted using immunofluorescence. RESULTS The EGFR domain III-targeting antibodies cetuximab, necitumumab, nimotuzumab, and matuzumab did not neutralize EGFRvIII activation. Chimeric monoclonal antibody 806 (ch806) neutralized EGFRvIII, but not wild-type (wt)EGFR activation. Panitumumab was the only antibody that neutralized both EGFRvIII and wtEGFR, leading to reduction of p-S6 signaling and superior in vitro and in vivo antitumor activity. Mechanistically, panitumumab induced recycling of receptor but not degradation as previously described. Panitumumab, via its unique avidity, stably cross-linked EGFRvIII to prevent its activation, while ch806 induced a marked reduction in the active EGFRvIII disulphide-bonded dimer. CONCLUSIONS We discovered a previously unknown major resistance mechanism in glioma in that most EGFR domain III-targeting antibodies do not neutralize EGFRvIII. The superior in vitro and in vivo antitumor activity of panitumumab supports further clinical testing of this antibody against EGFRvIII-stratified glioma.
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Affiliation(s)
- Sameer A Greenall
- Department of Oncology, Monash University and Monash Health, Clayton, Victoria, Australia.,Centre for Cancer Research, Hudson Institute of Medical Research, Clayton, Victoria, Australia.,Brain Cancer Discovery Collaborative, New South Wales, Australia
| | - Mathew McKenzie
- School of Life and Environmental Sciences, Deakin University, Geelong, Victoria, Australia.,Centre for Innate Immunity and Infectious Diseases, Hudson Institute of Medical Research, Clayton, Victoria, Australia.,Department of Molecular and Translational Science, Monash University, Clayton, Victoria, Australia
| | | | - Olan Dolezal
- CSIRO Manufacturing, Parkville, Victoria, Australia
| | | | - John Bentley
- CSIRO Manufacturing, Parkville, Victoria, Australia
| | - Mani Kuchibhotla
- Cancer Centre, Telethon Kids Institute, Nedlands, Western Australia, Australia
| | - Shengnan C Chen
- Centre for Cancer Research, Hudson Institute of Medical Research, Clayton, Victoria, Australia.,Department of Molecular and Translational Science, Monash University, Clayton, Victoria, Australia
| | - Kerrie L McDonald
- Brain Cancer Discovery Collaborative, New South Wales, Australia.,Cure Brain Cancer Biomarkers and Translational Research Group, Prince of Wales Clinical School, University of New South Wales, New South Wales, Australia
| | - Harley I Kornblum
- The Intellectual and Developmental Disabilities Research Center, University of California, Los Angeles, California, USA
| | - Raelene Endersby
- Brain Cancer Discovery Collaborative, New South Wales, Australia.,Cancer Centre, Telethon Kids Institute, Nedlands, Western Australia, Australia
| | | | - Terrance G Johns
- Brain Cancer Discovery Collaborative, New South Wales, Australia.,Cancer Centre, Telethon Kids Institute, Nedlands, Western Australia, Australia
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9
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EGFRvIII tumorigenicity requires PDGFRA co-signaling and reveals therapeutic vulnerabilities in glioblastoma. Oncogene 2021; 40:2682-2696. [PMID: 33707748 PMCID: PMC9159289 DOI: 10.1038/s41388-021-01721-9] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2020] [Revised: 02/15/2021] [Accepted: 02/18/2021] [Indexed: 01/31/2023]
Abstract
Focal amplification of epidermal growth factor receptor (EGFR) and its ligand-independent, constitutively active EGFRvIII mutant form are prominent oncogenic drivers in glioblastoma (GBM). The EGFRvIII gene rearrangement is considered to be an initiating event in the etiology of GBM, however, the mechanistic details of how EGFRvIII drives cellular transformation and tumor maintenance remain unclear. Here, we report that EGFRvIII demonstrates a reliance on PDGFRA co-stimulatory signaling during the tumorigenic process in a genetically engineered autochthonous GBM model. This dependency exposes liabilities that were leveraged using kinase inhibitors treatments in EGFRvIII-expressing GBM patient-derived xenografts (PDXs), where simultaneous pharmacological inhibition of EGFRvIII and PDGFRA kinase activities is necessary for anti-tumor efficacy. Our work establishes that EGFRvIII-positive tumors have unexplored vulnerabilities to targeted agents concomitant to the EGFR kinase inhibitor repertoire.
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10
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Mozumdar D, Doerner A, Zhang JY, Rafizadeh DN, Schepartz A. Discrete Coiled Coil Rotamers Form within the EGFRvIII Juxtamembrane Domain. Biochemistry 2020; 59:3965-3972. [PMID: 32941004 DOI: 10.1021/acs.biochem.0c00641] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Mutations in the epidermal growth factor receptor (EGFR) extracellular domain (ECD) are implicated in the development of glioblastoma multiforme (GBM), which is a highly aggressive form of brain cancer. Of particular interest to GBM is the EGFR variant known as EGFRvIII, which is distinguished by an in-frame deletion of exons 2-7, which encode ECD residues 6-273. Included within the deleted region is an autoinhibitory tether, whose absence, alongside unique disulfide interactions within the truncated ECD, supports assembly of a constitutively active asymmetric kinase dimer. Previous studies have shown that the binding of growth factors to the ECD of wild-type EGFR leads to the formation of two distinct coiled coil dimers in the cytoplasmic juxtamembrane (JM) segment, whose identities correlate with the downstream phenotype. One coiled coil contains leucine residues at the interhelix interface (EGF-type), whereas the other contains charged and polar side chains (TGF-α-type). It has been proposed that growth-factor-dependent structural changes in the ECD and adjacent transmembrane helix are transduced into distinct JM coiled coils. Here, we show that, in the absence of this growth-factor-induced signal, the JM of EGFRvIII adopts both EGF-type and TGF-α-type structures, providing direct evidence for this hypothesis. These studies confirm that the signals that define JM coiled coil identity begin within the ECD, and support a model in which growth-factor-induced conformational changes are transmitted from the ECD through the transmembrane helix to favor different coiled coil isomers within the JM.
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Affiliation(s)
- Deepto Mozumdar
- Department of Chemistry, Yale University, New Haven, Connecticut 06520, United States.,Department of Chemistry, University of California, Berkeley, California 94705, United States
| | - Amy Doerner
- Department of Chemistry, Yale University, New Haven, Connecticut 06520, United States
| | - Justin Y Zhang
- Department of Chemistry, Yale University, New Haven, Connecticut 06520, United States
| | - Diane N Rafizadeh
- Department of Chemistry, Yale University, New Haven, Connecticut 06520, United States
| | - Alanna Schepartz
- Department of Chemistry, University of California, Berkeley, California 94705, United States
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11
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Kopylov AM, Zavyalova EG, Pavlova GV, Pronin IN. [Theranostics for glioblastoma with monoclonal antibodies to the epidermal growth factor receptor]. ZHURNAL VOPROSY NEIROKHIRURGII IMENI N. N. BURDENKO 2020; 84:113-118. [PMID: 32649821 DOI: 10.17116/neiro202084031113] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
A review is devoted to analysis of the prospects of theranostics for multiform glioblastoma with monoclonal antibodies to the epidermal growth factor receptor (EGFR). Treatment of various malignancies demonstrated high potential of the use of EGFR. However, in case of glioblastoma, the effectiveness of monoclonal antibodies to EGFR is constrained by the absence of informative criteria for assessing the effectiveness of diagnosis and treatment of disease.
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Affiliation(s)
- A M Kopylov
- Lomonosov Moscow State University, Moscow, Russia.,Apto-Pharm LLC, Moscow, Russia
| | - E G Zavyalova
- Lomonosov Moscow State University, Moscow, Russia.,Apto-Pharm LLC, Moscow, Russia
| | - G V Pavlova
- Apto-Pharm LLC, Moscow, Russia.,Institute of Gene Biology of RAS, Moscow, Russia.,Burdenko Neurosurgical Center, Moscow, Russia
| | - I N Pronin
- Burdenko Neurosurgical Center, Moscow, Russia
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12
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EGFR vIII: An Oncogene with Ambiguous Role. JOURNAL OF ONCOLOGY 2019; 2019:1092587. [PMID: 32089685 PMCID: PMC7024087 DOI: 10.1155/2019/1092587] [Citation(s) in RCA: 35] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/19/2019] [Accepted: 11/22/2019] [Indexed: 12/21/2022]
Abstract
Epidermal growth factor receptor variant III (EGFRvIII) seems to constitute the perfect therapeutic target for glioblastoma (GB), as it is specifically present on up to 28–30% of GB cells. In case of other tumor types, expression and possible role of this oncogene still remain controversial. In spite of EGFRvIII mechanism of action being crucial for the design of small active anticancer molecules and immunotherapies, i.e., CAR-T technology, it is yet to be precisely defined. EGFRvIII is known to be resistant to degradation, but it is still unclear whether it heterodimerizes with EGF-activated wild-type EGFR (EGFRWT) or homodimerizes (including covalent homodimerization). Constitutive kinase activity of this mutated receptor is relatively low, and some researchers even claim that a nuclear, but not a membrane function, is crucial for its activity. Based on the analyses of recurrent tumors that are often lacking EGFRvIII expression despite its initial presence in corresponding primary foci, this oncogene is suggested to play a marginal role during later stages of carcinogenesis, while even in primary tumors EGFRvIII expression is detected only in a small percentage of tumor cells, undermining the rationality of EGFRvIII-targeting therapies. On the other hand, EGFRvIII-positive cells are resistant to apoptosis, more invasive, and characterized with enhanced proliferation rate. Moreover, expression of this oncogenic receptor was also postulated to be a marker of cancer stem cells. Opinions regarding the role that EGFRvIII plays in tumorigenesis and for tumor aggressiveness are clearly contradictory and, therefore, it is crucial not only to determine its mechanism of action, but also to unambiguously define its role at early and advanced cancer stages.
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13
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Karches CH, Benmebarek MR, Schmidbauer ML, Kurzay M, Klaus R, Geiger M, Rataj F, Cadilha BL, Lesch S, Heise C, Murr R, Vom Berg J, Jastroch M, Lamp D, Ding J, Duewell P, Niederfellner G, Sustmann C, Endres S, Klein C, Kobold S. Bispecific Antibodies Enable Synthetic Agonistic Receptor-Transduced T Cells for Tumor Immunotherapy. Clin Cancer Res 2019; 25:5890-5900. [PMID: 31285373 DOI: 10.1158/1078-0432.ccr-18-3927] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2018] [Revised: 04/25/2019] [Accepted: 06/25/2019] [Indexed: 12/22/2022]
Abstract
PURPOSE Genetically engineered T cells are powerful anticancer treatments but are limited by safety and specificity issues. We herein describe an MHC-unrestricted modular platform combining autologous T cells, transduced with a targetable synthetic agonistic receptor (SAR), with bispecific antibodies (BiAb) that specifically recruit and activate T cells for tumor killing. EXPERIMENTAL DESIGN BiAbs of different formats were generated by recombinant expression. T cells were retrovirally transduced with SARs. T-cell activation, proliferation, differentiation, and T-cell-induced lysis were characterized in three murine and human tumor models in vitro and in vivo. RESULTS Murine T cells transduced with SAR composed of an extracellular domain EGFRvIII fused to CD28 and CD3ζ signaling domains could be specifically recruited toward murine tumor cells expressing EpCAM by anti-EGFRvIII × anti-EpCAM BiAb. BiAb induced selective antigen-dependent activation, proliferation of SAR T cells, and redirected tumor cell lysis. Selectivity was dependent on the monovalency of the antibody for EGFRvIII. We identified FAS ligand as a major mediator of killing utilized by the T cells. Similarly, human SAR T cells could be specifically redirected toward mesothelin-expressing human pancreatic cancer cells. In vivo, treatment with SAR T cells and BiAb mediated antitumoral activity in three human pancreatic cancer cell xenograft models. Importantly, SAR activity, unlike CAR activity, was reversible in vitro and in vivo. CONCLUSIONS We describe a novel ACT platform with antitumor activity in murine and human tumor models with a distinct mode of action that combines adoptive T-cell therapy with bispecific antibodies.
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Affiliation(s)
- Clara H Karches
- Center of Integrated Protein Science Munich (CIPS-M) and Division of Clinical Pharmacology, Department of Medicine IV, Klinikum der Universität München, LMU Munich, Germany, Member of the German Center for Lung Research (DZL)
| | - Mohamed-Reda Benmebarek
- Center of Integrated Protein Science Munich (CIPS-M) and Division of Clinical Pharmacology, Department of Medicine IV, Klinikum der Universität München, LMU Munich, Germany, Member of the German Center for Lung Research (DZL)
| | - Moritz L Schmidbauer
- Center of Integrated Protein Science Munich (CIPS-M) and Division of Clinical Pharmacology, Department of Medicine IV, Klinikum der Universität München, LMU Munich, Germany, Member of the German Center for Lung Research (DZL)
| | - Mathias Kurzay
- Center of Integrated Protein Science Munich (CIPS-M) and Division of Clinical Pharmacology, Department of Medicine IV, Klinikum der Universität München, LMU Munich, Germany, Member of the German Center for Lung Research (DZL)
| | - Richard Klaus
- Center of Integrated Protein Science Munich (CIPS-M) and Division of Clinical Pharmacology, Department of Medicine IV, Klinikum der Universität München, LMU Munich, Germany, Member of the German Center for Lung Research (DZL)
| | | | - Felicitas Rataj
- Center of Integrated Protein Science Munich (CIPS-M) and Division of Clinical Pharmacology, Department of Medicine IV, Klinikum der Universität München, LMU Munich, Germany, Member of the German Center for Lung Research (DZL)
| | - Bruno L Cadilha
- Center of Integrated Protein Science Munich (CIPS-M) and Division of Clinical Pharmacology, Department of Medicine IV, Klinikum der Universität München, LMU Munich, Germany, Member of the German Center for Lung Research (DZL)
| | - Stefanie Lesch
- Center of Integrated Protein Science Munich (CIPS-M) and Division of Clinical Pharmacology, Department of Medicine IV, Klinikum der Universität München, LMU Munich, Germany, Member of the German Center for Lung Research (DZL)
| | - Constanze Heise
- Center of Integrated Protein Science Munich (CIPS-M) and Division of Clinical Pharmacology, Department of Medicine IV, Klinikum der Universität München, LMU Munich, Germany, Member of the German Center for Lung Research (DZL)
| | - Ramona Murr
- Roche Innovation Center Zurich, Schlieren, Switzerland
| | - Johannes Vom Berg
- Institute of Laboratory Animal Science, University of Zurich, Zurich, Switzerland
| | - Martin Jastroch
- Helmholtz Diabetes Center and German Diabetes Center (DZD), Helmholtz Zentrum München, Neuherberg, Germany
| | - Daniel Lamp
- Helmholtz Diabetes Center and German Diabetes Center (DZD), Helmholtz Zentrum München, Neuherberg, Germany
| | - Jian Ding
- TCR Therapeutics, Cambridge, Massachusetts
| | - Peter Duewell
- Center of Integrated Protein Science Munich (CIPS-M) and Division of Clinical Pharmacology, Department of Medicine IV, Klinikum der Universität München, LMU Munich, Germany, Member of the German Center for Lung Research (DZL)
| | | | | | - Stefan Endres
- Center of Integrated Protein Science Munich (CIPS-M) and Division of Clinical Pharmacology, Department of Medicine IV, Klinikum der Universität München, LMU Munich, Germany, Member of the German Center for Lung Research (DZL)
| | | | - Sebastian Kobold
- Center of Integrated Protein Science Munich (CIPS-M) and Division of Clinical Pharmacology, Department of Medicine IV, Klinikum der Universität München, LMU Munich, Germany, Member of the German Center for Lung Research (DZL).
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Floss DM, Scheller J. Naturally occurring and synthetic constitutive-active cytokine receptors in disease and therapy. Cytokine Growth Factor Rev 2019; 47:1-20. [PMID: 31147158 DOI: 10.1016/j.cytogfr.2019.05.007] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2019] [Accepted: 05/15/2019] [Indexed: 02/07/2023]
Abstract
Cytokines control immune related events and are critically involved in a plethora of patho-physiological processes including autoimmunity and cancer development. Mutations which cause ligand-independent, constitutive activation of cytokine receptors are quite frequently found in diseases. Many constitutive-active cytokine receptor variants have been directly connected to disease development and mechanistically analyzed. Nature's solutions to generate constitutive cytokine receptors has been recently adopted by synthetic cytokine receptor biology, with the goal to optimize immune therapeutics. Here, CAR T cell immmunotherapy represents the first example to combine synthetic biology with genetic engineering during therapy. Hence, constitutive-active cytokine receptors are therapeutic targets, but also emerging tools to improve or modulate immunotherapeutic strategies. This review gives a comprehensive insight into the field of naturally occurring and synthetic constitutive-active cytokine receptors.
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Affiliation(s)
- Doreen M Floss
- Institute of Biochemistry and Molecular Biology II, Medical Faculty, Heinrich-Heine-University, Düsseldorf, Germany.
| | - Jürgen Scheller
- Institute of Biochemistry and Molecular Biology II, Medical Faculty, Heinrich-Heine-University, Düsseldorf, Germany
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15
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Oncogenic mutations at the EGFR ectodomain structurally converge to remove a steric hindrance on a kinase-coupled cryptic epitope. Proc Natl Acad Sci U S A 2019; 116:10009-10018. [PMID: 31028138 DOI: 10.1073/pnas.1821442116] [Citation(s) in RCA: 37] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
Epidermal growth factor receptor (EGFR) signaling is initiated by a large ligand-favored conformational change of the extracellular domain (ECD) from a closed, self-inhibited tethered monomer, to an open untethered state, which exposes a loop required for strong dimerization and activation. In glioblastomas (GBMs), structurally heterogeneous missense and deletion mutations concentrate at the ECD for unclear reasons. We explore the conformational impact of GBM missense mutations, combining elastic network models (ENMs) with multiple molecular dynamics (MD) trajectories. Our simulations reveal that the main missense class, located at the I-II interface away from the self-inhibitory tether, can unexpectedly favor spontaneous untethering to a compact intermediate state, here validated by small-angle X-ray scattering (SAXS). Significantly, such intermediate is characterized by the rotation of a large ECD fragment (N-TR1), deleted in the most common GBM mutation, EGFRvIII, and that makes accessible a cryptic epitope characteristic of cancer cells. This observation suggested potential structural equivalence of missense and deletion ECD changes in GBMs. Corroborating this hypothesis, our FACS, in vitro, and in vivo data demonstrate that entirely different ECD variants all converge to remove N-TR1 steric hindrance from the 806-epitope, which we show is allosterically coupled to an intermediate kinase and hallmarks increased oncogenicity. Finally, the detected extraintracellular coupling allows for synergistic cotargeting of the intermediate with mAb806 and inhibitors, which is proved herein.
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16
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Stec W, Rosiak K, Treda C, Smolarz M, Peciak J, Pacholczyk M, Lenart A, Grzela D, Stoczynska-Fidelus E, Rieske P. Cyclic trans-phosphorylation in a homodimer as the predominant mechanism of EGFRvIII action and regulation. Oncotarget 2018; 9:8560-8572. [PMID: 29492217 PMCID: PMC5823601 DOI: 10.18632/oncotarget.24058] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2017] [Accepted: 12/29/2017] [Indexed: 11/25/2022] Open
Abstract
Despite intensive research no therapies targeted against the oncogenic EGFRvIII are present in the clinic. One of the reasons is the elusive nature of the molecular structure and activity of the truncated receptor. The recent publications indicate the EGF-bound wild-type EGFR to trans-phosphorylate the EGFRvIII initiating aberrant signaling cascade. The elevated stability of the mutant receptor contributes towards oncogenic potential, preventing termination of signaling by receptor degradation. Here, we show that inhibition of phosphatases leads to a marked increase in phosphorylation of wild-type EGFR and EGFRvIII, indicating that both undergo cyclic rounds of phosphorylation and dephosphorylation on all investigated tyrosine residues, including Tyr1045. Still, we observe elevated stability of the mutant receptor, suggesting phosphorylation as insufficient to cause degradation. Hyperphosphorylation of EGFRvIII was hindered only by EGFR tyrosine kinase inhibitors. Co-immunoprecipitation as well as semi-native Western blotting structural analyses together with functional investigation of EGFRvIII's phosphorylation following depletion of wild-type EGFR by shRNA or EGF-mediated degradation indicated homodimerization as the predominant quaternary structure of the mutant receptor. Dimers were observed only under non-reducing conditions, suggesting that homodimerization is mediated by covalent bonds. Previous reports indicated cysteine at position 16 to mediate covalent homodimerization. Upon its substitution to serine, we have observed impaired formation of dimers and lower phosphorylation levels of the mutated oncogene. Based on the obtained results we propose that EGFRvIII is predominantly regulated dynamically by phosphatases that counteract the process of trans-phosphorylation occurring within the homodimers.
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Affiliation(s)
- Wojciech Stec
- Research and Development Unit, Celther Polska Ltd., Lodz, Poland
| | - Kamila Rosiak
- Research and Development Unit, Celther Polska Ltd., Lodz, Poland.,Department of Tumor Biology, Medical University of Lodz, Lodz, Poland
| | - Cezary Treda
- Research and Development Unit, Celther Polska Ltd., Lodz, Poland.,Department of Tumor Biology, Medical University of Lodz, Lodz, Poland
| | - Maciej Smolarz
- Research and Development Unit, Celther Polska Ltd., Lodz, Poland
| | - Joanna Peciak
- Research and Development Unit, Celther Polska Ltd., Lodz, Poland.,Department of Tumor Biology, Medical University of Lodz, Lodz, Poland
| | - Marcin Pacholczyk
- Research and Development Unit, Celther Polska Ltd., Lodz, Poland.,Institute of Automatic Control, Silesian University of Technology, Gliwice, Poland
| | - Anna Lenart
- Research and Development Unit, Celther Polska Ltd., Lodz, Poland
| | - Dawid Grzela
- Research and Development Unit, Celther Polska Ltd., Lodz, Poland
| | - Ewelina Stoczynska-Fidelus
- Research and Development Unit, Celther Polska Ltd., Lodz, Poland.,Department of Tumor Biology, Medical University of Lodz, Lodz, Poland
| | - Piotr Rieske
- Research and Development Unit, Celther Polska Ltd., Lodz, Poland.,Department of Tumor Biology, Medical University of Lodz, Lodz, Poland.,Research and Development Unit, Personather Ltd., Lodz, Poland
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17
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Yu S, Zhang Y, Pan Y, Cheng C, Sun Y, Chen H. The non-small cell lung cancer EGFR extracellular domain mutation, M277E, is oncogenic and drug-sensitive. Onco Targets Ther 2017; 10:4507-4515. [PMID: 28979142 PMCID: PMC5602469 DOI: 10.2147/ott.s131999] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
PURPOSE To identify novel oncogenic mutations in non-small cell lung cancer patient specimens that lack mutations in known targetable genes ("pan-negative" patients). METHODS Comprehensive mutational analyses were performed on 1,356 lung adenocarcinoma specimens. In this cohort of patients, common lung cancer oncogenic driver mutations were detected in the epidermal growth factor receptor (EGFR) kinase domain, the human epidermal growth factor receptor 2 kinase domain, as well as the KRAS, BRAF, ALK, ROS1 and RET genes. A sub-cohort of pan-negative patient specimens was assayed for mutations in the EGFR extracellular domain (ECD). Additionally, EGFR mutant NIH-3T3 stable cell lines were constructed and assessed for protein content, anchorage-independent growth, and tumor formation in xenograft models to identify oncogenic mutations. BaF3 lymphocytes were also used to test sensitivities of the mutations to tyrosine kinase inhibitors. RESULTS In pan-negative lung adenocarcinoma cases, a novel oncogenic EGFR ECD mutation was identified (M277E). EGFR M277E mutations encoded oncoproteins that transformed NIH-3T3 cells to grow in the absence of exogenous epidermal growth factor. Transformation was further evidenced by anchorage-independent growth and tumor formation in immunocompromised xenograft mouse models. Finally, as seen in the canonical EGFR L858R mutation, the M277E mutation conferred sensitivity to both erlotinib and cetuximab in BaF3 cell lines and to erlotinib in xenograft models. CONCLUSION Here, a new EGFR driver mutation, M277E, was identified in the ECD of a lung adenocarcinoma specimen. For patients with M277E-mutant lung adenocarcinoma who experienced disease recurrence, treatment with an EGFR tyrosine kinase inhibitor may predict good prognosis.
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Affiliation(s)
- Su Yu
- Department of Thoracic Surgery, Fudan University Shanghai Cancer Center, Shanghai, China.,Cancer Research Center, Fudan University Shanghai Cancer Center, Shanghai, China
| | - Yang Zhang
- Department of Thoracic Surgery, Fudan University Shanghai Cancer Center, Shanghai, China
| | - Yunjian Pan
- Department of Thoracic Surgery, Fudan University Shanghai Cancer Center, Shanghai, China
| | - Chao Cheng
- Department of Thoracic Surgery, Fudan University Shanghai Cancer Center, Shanghai, China.,Department of Oncology, Shanghai Medical College, Fudan University, Shanghai, China
| | - Yihua Sun
- Department of Thoracic Surgery, Fudan University Shanghai Cancer Center, Shanghai, China.,Department of Oncology, Shanghai Medical College, Fudan University, Shanghai, China
| | - Haiquan Chen
- Department of Thoracic Surgery, Fudan University Shanghai Cancer Center, Shanghai, China.,Cancer Research Center, Fudan University Shanghai Cancer Center, Shanghai, China.,Department of Oncology, Shanghai Medical College, Fudan University, Shanghai, China.,Institutes of Biomedical Sciences, Fudan University, Shanghai, China
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18
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Chistiakov DA, Chekhonin IV, Chekhonin VP. The EGFR variant III mutant as a target for immunotherapy of glioblastoma multiforme. Eur J Pharmacol 2017; 810:70-82. [DOI: 10.1016/j.ejphar.2017.05.064] [Citation(s) in RCA: 39] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2017] [Revised: 05/15/2017] [Accepted: 05/31/2017] [Indexed: 12/26/2022]
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19
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A novel, somatic, transforming mutation in the extracellular domain of Epidermal Growth Factor Receptor identified in myeloproliferative neoplasm. Sci Rep 2017; 7:2467. [PMID: 28550306 PMCID: PMC5446393 DOI: 10.1038/s41598-017-02655-7] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2016] [Accepted: 04/18/2017] [Indexed: 11/08/2022] Open
Abstract
We describe a novel ERBB1/EGFR somatic mutation (p. C329R; c.985 T > C) identified in a patient with JAK2V617F Polycythaemia Vera (PV). This substitution affects a conserved cysteine residue in EGFR domain 2 and leads to the formation of a ligand-independent covalent receptor dimer, associated with increased transforming potential. Aberrant signalling from the EGFRC329R receptor is cell type-dependent and in the TF1.8 erythroid cell line expression of this mutant suppresses EPO-induced differentiation. Clonal analysis shows that the dominant JAK2V617F-positive clone in this PV patient harbors EGFRC329R, thus this mutation may contribute to clonal expansion. Somatic mutations affecting other ERBB and related receptor tyrosine kinases are observed in myeloproliferative neoplasms (MPN), and we show elevated EGFR levels in MPN samples, consistent with previous reports. Thus activation of this group of receptors, via multiple mechanisms, may contribute to clonal growth and survival of the JAK2V617F disease clone in MPN.
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20
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Xu H, Zong H, Ma C, Ming X, Shang M, Li K, He X, Du H, Cao L. Epidermal growth factor receptor in glioblastoma. Oncol Lett 2017; 14:512-516. [PMID: 28693199 PMCID: PMC5494611 DOI: 10.3892/ol.2017.6221] [Citation(s) in RCA: 84] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2016] [Accepted: 03/21/2017] [Indexed: 12/11/2022] Open
Abstract
Mutations in the epidermal growth factor receptor (EGFR) are commonly occurring in glioblastoma. Enhanced activation of EGFR can occur through a variety of different mechanisms, both ligand-dependent and ligand-independent. Numerous evidence has suggested that EGFR is overexpressed in most of primary glioblastomas and some of the secondary glioblastomas and is characteristic of more aggressive glioblastoma phenotypes. Additionally, recent studies have revealed that wild-type EGFR, and to a greater extent hyper-activating EGFR mutants induced a substantial upregulation of Fyn expression. Furthermore, it was determined that Fyn expression is upregulated across a panel of patient-derived glioblastoma stem cells (GSCs) relative to normal progenitor controls. Moreover, researchers are continuously involved in elucidation of novel mechanism linking EGFR EGFR-expressing glioblastoma. The present review highlights current aspects of EGFR receptor in glioblastoma and concludes that the concept of EGFR signaling and related receptors and associated factors is evolving, however, it needs detailed evaluation for future clinical applications in cancer patients.
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Affiliation(s)
- Hongsheng Xu
- Department of Neurosurgery, Central Hospital of Xuzhou, Affiliated Hospital of Southeast University, Xuzhou, Jiangsu 221009, P.R. China
| | - Hailiang Zong
- Department of Neurosurgery, Central Hospital of Xuzhou, Affiliated Hospital of Southeast University, Xuzhou, Jiangsu 221009, P.R. China
| | - Chong Ma
- Department of Neurosurgery, Central Hospital of Xuzhou, Affiliated Hospital of Southeast University, Xuzhou, Jiangsu 221009, P.R. China
| | - Xing Ming
- Department of Neurosurgery, Central Hospital of Xuzhou, Affiliated Hospital of Southeast University, Xuzhou, Jiangsu 221009, P.R. China
| | - Ming Shang
- Department of Neurosurgery, Central Hospital of Xuzhou, Affiliated Hospital of Southeast University, Xuzhou, Jiangsu 221009, P.R. China
| | - Kai Li
- Department of Neurosurgery, Central Hospital of Xuzhou, Affiliated Hospital of Southeast University, Xuzhou, Jiangsu 221009, P.R. China
| | - Xiaoguang He
- Department of Neurosurgery, Central Hospital of Xuzhou, Affiliated Hospital of Southeast University, Xuzhou, Jiangsu 221009, P.R. China
| | - Hai Du
- Department of Neurosurgery, Central Hospital of Xuzhou, Affiliated Hospital of Southeast University, Xuzhou, Jiangsu 221009, P.R. China
| | - Lei Cao
- Department of Neurosurgery, Central Hospital of Xuzhou, Affiliated Hospital of Southeast University, Xuzhou, Jiangsu 221009, P.R. China
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Cyclin-dependent kinase 7 is a therapeutic target in high-grade glioma. Oncogenesis 2017; 6:e336. [PMID: 28504693 PMCID: PMC5523066 DOI: 10.1038/oncsis.2017.33] [Citation(s) in RCA: 43] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2016] [Revised: 02/16/2017] [Accepted: 03/27/2017] [Indexed: 12/12/2022] Open
Abstract
High-grade glioma (HGG) is an incurable brain cancer. The transcriptomes of cells within HGG tumors are highly heterogeneous. This renders the tumors unresponsive or able to adapt to therapeutics targeted at single pathways, thereby causing treatment failure. To overcome this, we focused on cyclin-dependent kinase 7 (CDK7), a ubiquitously expressed molecule involved in two major drivers of HGG pathogenesis: cell cycle progression and RNA polymerase-II-based transcription. We tested the activity of THZ1, an irreversible CDK7 inhibitor, on patient-derived primary HGG cell lines and ex vivo HGG patient tissue slices, using proliferation assays, microarray analysis, high-resolution respirometry, cell cycle analysis and in vivo tumor orthografts. The cellular processes affected by CDK7 inhibition were analyzed by reverse transcriptase–quantitative PCR, western blot, flow cytometry and immunofluorescence. THZ1 perturbed the transcriptome and disabled CDK activation, leading to cell cycle arrest at G2 and DNA damage. THZ1 halted transcription of the nuclear-encoded mitochondrial ribosomal genes, reducing mitochondrial translation and oxidative respiration. It also inhibited the expression of receptor tyrosine kinases such as epidermal growth factor receptor (EGFR) and platelet-derived growth factor receptor-α (PDGFR-α), reducing signaling flux through the AKT, extracellular-signal-regulated kinase 1/2 (ERK1/2) and signal transducer and activator of transcription 3 (STAT3) downstream pathways. Finally, THZ1 disrupted nucleolar, Cajal body and nuclear speckle formation, resulting in reduced cytosolic translation and malfunction of the spliceosome and thus leading to aberrant mRNA processing. These findings indicate that CDK7 is crucial for gliomagenesis, validate CDK7 as a therapeutic target and provide new insight into the cellular processes that are affected by THZ1 and induce antitumor activity.
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Greenall SA, Adams TE, Johns TG. Incomplete target neutralization by the anti-cancer antibody rilotumumab. MAbs 2016; 8:246-52. [PMID: 26750997 DOI: 10.1080/19420862.2015.1122149] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
The antibody rilotumumab, which has been tested in multiple Phase 2 and Phase 3 trials, has been reported to neutralize hepatocyte growth factor (HGF), the ligand for the oncogene MET. However, we report that rilotumumab does not prevent HGF from directly binding to MET on conventional and primary patient-derived human gliomasphere lines, a trait driven by the HGF α-chain, which remains free to engage cell-surface glycosaminoglycans and the receptor MET. This binding induces MET phosphorylation, initiates robust AKT and ERK signaling and potentiates biological effects such as cell scattering. This partial antagonism was highly exacerbated in the presence of activated epidermal growth factor receptor, which is common in several cancers. Hence, we confirm that rilotumumab is only a partial antagonist of HGF activity, a finding that has considerable implications for the therapeutic use of rilotumumab.
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Affiliation(s)
- Sameer A Greenall
- a Oncogenic Signalling Laboratory and Brain Cancer Discovery Collaborative, Centre for Cancer Research, Hudson Institute of Medical Research , 27-31 Wright Street, Clayton , VIC 3168 , Australia.,b Monash University, Wellington Parade , Clayton , VIC 3800 , Australia.,c Biomedical Manufacturing Program, Commonwealth Scientific and Industrial Research Organisation , 343 Royal Parade, Parkville , VIC 3052 , Australia
| | - Timothy E Adams
- c Biomedical Manufacturing Program, Commonwealth Scientific and Industrial Research Organisation , 343 Royal Parade, Parkville , VIC 3052 , Australia
| | - Terrance G Johns
- a Oncogenic Signalling Laboratory and Brain Cancer Discovery Collaborative, Centre for Cancer Research, Hudson Institute of Medical Research , 27-31 Wright Street, Clayton , VIC 3168 , Australia.,b Monash University, Wellington Parade , Clayton , VIC 3800 , Australia
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Aptamer targeting EGFRvIII mutant hampers its constitutive autophosphorylation and affects migration, invasion and proliferation of glioblastoma cells. Oncotarget 2016; 6:37570-87. [PMID: 26461476 PMCID: PMC4741949 DOI: 10.18632/oncotarget.6066] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2015] [Accepted: 09/23/2015] [Indexed: 12/21/2022] Open
Abstract
Glioblastoma Multiforme (GBM) is the most common and aggressive human brain tumor, associated with very poor survival despite surgery, radiotherapy and chemotherapy.The epidermal growth factor receptor (EGFR) and the platelet-derived growth factor receptor β (PDGFRβ) are hallmarks in GBM with driving roles in tumor progression. In approximately half of the tumors with amplified EGFR, the EGFRvIII truncated extracellular mutant is detected. EGFRvIII does not bind ligands, is highly oncogenic and its expression confers resistance to EGFR tyrosine kinase inhibitors (TKIs). It has been demonstrated that EGFRvIII-dependent cancers may escape targeted therapy by developing dependence on PDGFRβ signaling, thus providing a strong rationale for combination therapy aimed at blocking both EGFRvIII and PDGFRβsignaling.We have recently generated two nuclease resistant RNA aptamers, CL4 and Gint4.T, as high affinity ligands and inhibitors of the human wild-type EGFR (EGFRwt) and PDGFRβ, respectively.Herein, by different approaches, we demonstrate that CL4 aptamer binds to the EGFRvIII mutant even though it lacks most of the extracellular domain. As a consequence of binding, the aptamer inhibits EGFRvIII autophosphorylation and downstream signaling pathways, thus affecting migration, invasion and proliferation of EGFRvIII-expressing GBM cell lines.Further, we show that targeting EGFRvIII by CL4, as well as by EGFR-TKIs, erlotinib and gefitinib, causes upregulation of PDGFRβ. Importantly, CL4 and gefitinib cooperate with the anti-PDGFRβ Gint4.T aptamer in inhibiting cell proliferation.The proposed aptamer-based strategy could have impact on targeted molecular cancer therapies and may result in progresses against GBMs.
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A NOX2/Egr-1/Fyn pathway delineates new targets for TKI-resistant malignancies. Oncotarget 2016; 6:23631-46. [PMID: 26136341 PMCID: PMC4695141 DOI: 10.18632/oncotarget.4604] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2015] [Accepted: 06/12/2015] [Indexed: 12/13/2022] Open
Abstract
Tyrosine kinase inhibitors (TKI) have improved CML response rates, and some are effective against resistance-promoting point mutations in BCR-ABL1. However, in the absence of point mutations, resistance still occurs. Here, we identify a novel pathway mediating resistance which connects p47phox, the organizer subunit of NADPH oxidase-2 (NOX2), with early growth response-1 (Egr-1) and the Src family kinase Fyn. We found up-regulation of p47phox, Egr-1, and Fyn mRNA and protein using paired isogenic CML cell lines and mined data. Isolation of CD34+ cells and tissue microarray staining from blast crisis CML patients confirmed in vivo over-expression of components of this pathway. Knockdown studies revealed that p47phox modulated reactive oxygen species and Egr-1 expression, which, in turn, controlled Fyn expression. Interestingly, Fyn knockdown sensitized TKI-resistant cells to dasatinib, a dual BCR-ABL1/Src inhibitor. Egr-1 knockdown had similar effects, indicating the utility of targeting Fyn expression over activation. Pointedly, p47phox knockdown also restored TKI-sensitivity, indicating that targeting the NOX2 complex can overcome resistance. The NOX2/Egr-1/Fyn pathway was also conserved within TKI-resistant EGFRΔIII-expressing glioblastoma and patient-derived glioblastoma stem cells. Thus, our findings suggest that targeting the NOX2/Egr-1/Fyn pathway may have clinical implications within multiple cancer types; particularly where efficacy of TKI is compromised.
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Higginbotham JN, Zhang Q, Jeppesen DK, Scott AM, Manning HC, Ochieng J, Franklin JL, Coffey RJ. Identification and characterization of EGF receptor in individual exosomes by fluorescence-activated vesicle sorting. J Extracell Vesicles 2016; 5:29254. [PMID: 27345057 PMCID: PMC4921784 DOI: 10.3402/jev.v5.29254] [Citation(s) in RCA: 88] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2015] [Revised: 04/22/2016] [Accepted: 04/27/2016] [Indexed: 01/05/2023] Open
Abstract
Exosomes are small, 40–130 nm secreted extracellular vesicles that recently have become the subject of intense focus as agents of intercellular communication, disease biomarkers and potential vehicles for drug delivery. It is currently unknown whether a cell produces different populations of exosomes with distinct cargo and separable functions. To address this question, high-resolution methods are needed. Using a commercial flow cytometer and directly labelled fluorescent antibodies, we show the feasibility of using fluorescence-activated vesicle sorting (FAVS) to analyse and sort individual exosomes isolated by sequential ultracentrifugation from the conditioned medium of DiFi cells, a human colorectal cancer cell line. EGFR and the exosomal marker, CD9, were detected on individual DiFi exosomes by FAVS; moreover, both markers were identified by high-resolution stochastic optical reconstruction microscopy on individual, approximately 100 nm vesicles from flow-sorted EGFR/CD9 double-positive exosomes. We present evidence that the activation state of EGFR can be assessed in DiFi-derived exosomes using a monoclonal antibody (mAb) that recognizes “conformationally active” EGFR (mAb 806). Using human antigen-specific antibodies, FAVS was able to detect human EGFR and CD9 on exosomes isolated from the plasma of athymic nude mice bearing DiFi tumour xenografts. Multicolour FAVS was used to simultaneously identify CD9, EGFR and an EGFR ligand, amphiregulin (AREG), on human plasma-derived exosomes from 3 normal individuals. These studies demonstrate the feasibility of FAVS to both analyse and sort individual exosomes based on specific cell-surface markers. We propose that FAVS may be a useful tool to monitor EGFR and AREG in circulating exosomes from individuals with colorectal cancer and possibly other solid tumours.
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Affiliation(s)
- James N Higginbotham
- Department of Medicine, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Qin Zhang
- Department of Medicine, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Dennis K Jeppesen
- Department of Medicine, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Andrew M Scott
- Tumour Targeting Laboratory, Olivia Newton-John Cancer Research Institute, Heidelberg, VIC, Australia.,Department of Molecular Imaging and Therapy, Austin Health, Heidelberg, VIC, Australia.,School of Cancer Medicine, La Trobe University, Melbourne, VIC, Australia
| | - H Charles Manning
- Center for Molecular Probes, Vanderbilt University Institute of Imaging Science, Nashville, TN, USA.,Department of Radiology and Radiological Sciences, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Josiah Ochieng
- Departments of Biochemistry and Cancer Biology, Meharry Medical College, Nashville, TN, USA
| | - Jeffrey L Franklin
- Department of Medicine, Vanderbilt University Medical Center, Nashville, TN, USA.,Department of Cell and Developmental Biology, Nashville, TN, USA.,Department of Veterans Affairs Medical Center, Nashville, TN, USA
| | - Robert J Coffey
- Department of Medicine, Vanderbilt University Medical Center, Nashville, TN, USA.,Department of Cell and Developmental Biology, Nashville, TN, USA.,Department of Veterans Affairs Medical Center, Nashville, TN, USA;
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26
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Treda C, Popeda M, Ksiazkiewicz M, Grzela DP, Walczak MP, Banaszczyk M, Peciak J, Stoczynska-Fidelus E, Rieske P. EGFR Activation Leads to Cell Death Independent of PI3K/AKT/mTOR in an AD293 Cell Line. PLoS One 2016; 11:e0155230. [PMID: 27153109 PMCID: PMC4859505 DOI: 10.1371/journal.pone.0155230] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2015] [Accepted: 04/26/2016] [Indexed: 12/14/2022] Open
Abstract
The Epidermal Growth Factor Receptor (EGFR) and its mutations contribute in various ways to tumorigenesis and biology of human cancers. They are associated with tumor proliferation, progression, drug resistance and the process of apoptosis. There are also reports that overexpression and activation of wild-type EGFR may lead to cell apoptosis. To study this phenomenon, we overexpressed in an AD293 cell line two most frequently observed forms of the EGFR receptor: wild-type and the constitutively active mutant–EGFR variant III (EGFRvIII). Then, we compared the effect of EGF stimulation on cell viability and downstream EGFR signaling. AD293 cells overexpressing wild-type EGFR, despite a significant proliferation increase in serum supplemented medium, underwent apoptosis after EGF stimulation in serum free conditions. EGFRvIII expressing cells, however, were unaffected by either serum starvation or EGF treatment. The effect of EGF was completely neutralized by tyrosine kinase inhibitors (TKIs), indicating the specificity of this observation. Moreover, apoptosis was not prevented by inhibiting EGFR downstream proteins (PI3K, AKT and mTOR). Here we showed another EGFR function, dependent on environmental factors, which could be employed in therapy and drug design. We also proposed a new tool for EGFR inhibitor analysis.
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Affiliation(s)
- Cezary Treda
- Department of Research and Development, Celther Polska Ltd., Lodz, Poland
- * E-mail:
| | - Marta Popeda
- Department of Research and Development, Celther Polska Ltd., Lodz, Poland
| | | | - Dawid P. Grzela
- Department of Research and Development, Celther Polska Ltd., Lodz, Poland
| | - Maciej P. Walczak
- Department of Research and Development, Celther Polska Ltd., Lodz, Poland
| | - Mateusz Banaszczyk
- Department of Research and Development, Celther Polska Ltd., Lodz, Poland
- Department of Tumor Biology, Medical University of Lodz, Lodz, Poland
| | - Joanna Peciak
- Department of Research and Development, Celther Polska Ltd., Lodz, Poland
- Department of Tumor Biology, Medical University of Lodz, Lodz, Poland
| | - Ewelina Stoczynska-Fidelus
- Department of Research and Development, Celther Polska Ltd., Lodz, Poland
- Department of Tumor Biology, Medical University of Lodz, Lodz, Poland
| | - Piotr Rieske
- Department of Research and Development, Celther Polska Ltd., Lodz, Poland
- Department of Tumor Biology, Medical University of Lodz, Lodz, Poland
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27
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Epstein DM, Buck E. Old dog, new tricks: extracellular domain arginine methylation regulates EGFR function. J Clin Invest 2015; 125:4320-2. [PMID: 26571394 DOI: 10.1172/jci85001] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023] Open
Abstract
Conventional wisdom holds that methylation of RTKs should be restricted to intracellular sites. Alterations--such as deletion, mutation, and proteolytic cleavage events--to the extracellular ligand binding and dimer interface domains of the EGFR can induce EGFR dimer formation, leading to aberrant receptor activation and oncogenic activity. Recently, the extracellular domain of EGFR was also shown to be methylated, suggesting that posttranslational protein methylation events directed to the extracellular dimer interface provide another mechanism to regulate the EGFR activation state by modulating receptor dimerization. Critically, these methylation events abrogate response to conformation-specific therapeutic antibodies such as cetuximab. In this issue of the JCI, Liao et al. investigate the role of protein arginine methyltransferase I (PRMT1) in regulating EGFR function in colorectal cancer. The authors provide evidence that methylation of R198 and R200 within the dimer interface enhances growth factor ligand binding and cetuximab resistance through induction and stabilization of the active EGFR dimer conformation. Delineation of these and other subtleties involved in oncogenic RTK activation and their response to targeted therapies should facilitate the development of improved antibody-based treatments.
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28
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Guo G, Gong K, Wohlfeld B, Hatanpaa KJ, Zhao D, Habib AA. Ligand-Independent EGFR Signaling. Cancer Res 2015; 75:3436-41. [PMID: 26282175 DOI: 10.1158/0008-5472.can-15-0989] [Citation(s) in RCA: 127] [Impact Index Per Article: 14.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2015] [Accepted: 05/06/2015] [Indexed: 12/31/2022]
Abstract
Constitutive activation of the EGFR is common in cancer due to EGFR wild-type (EGFRwt) overexpression or the presence of mutant EGFR. Signaling by constitutively active NSCLC EGFR mutants or the EGFRvIII mutant in glioblastoma has been studied intensively and the downstream signals are known. Normally, the EGFRwt is activated when it is exposed to ligand, resulting in activation of canonical signals such as ERK and Akt. The EGFRwt also becomes tyrosine phosphorylated and constitutively activated without ligand when it is overexpressed, but downstream signals are unclear. Recent studies have identified a noncanonical form of signaling triggered by EGFRwt exclusively in the absence of ligand that does not involve ERK or Akt activation but, instead, results in activation of the transcription factor IRF3. The addition of ligand turns off IRF3-dependent transcription and activates ERK and Akt. Thus, the EGFR triggers distinct and mutually exclusive signaling networks, depending on the presence of ligand. Furthermore, noncanonical EGFRwt signaling may influence response to treatment in cancer. Also, there are reports of both synergistic and antagonistic interactions between ligand-dependent EGFRwt and EGFRvIII signaling. Here, we discuss ligand-independent EGFR signal transduction by oncogenic EGFR mutants and EGFRwt, and review the interplay between EGFRwt and EGFRvIII.
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Affiliation(s)
- Gao Guo
- Department of Neurology and Neurotherapeutics, The University of Texas Southwestern Medical Center, Dallas, Texas
| | - Ke Gong
- Department of Neurology and Neurotherapeutics, The University of Texas Southwestern Medical Center, Dallas, Texas
| | - Bryan Wohlfeld
- Department of Neurosurgery, The University of Texas Southwestern Medical Center, Dallas, Texas. VA North Texas Health Care System, Dallas, Texas
| | - Kimmo J Hatanpaa
- Department of Pathology, The University of Texas Southwestern Medical Center, Dallas, Texas
| | - Dawen Zhao
- Department of Radiology, The University of Texas Southwestern Medical Center, Dallas, Texas
| | - Amyn A Habib
- Department of Neurology and Neurotherapeutics, The University of Texas Southwestern Medical Center, Dallas, Texas. VA North Texas Health Care System, Dallas, Texas.
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29
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Greenall SA, Donoghue JF, Van Sinderen M, Dubljevic V, Budiman S, Devlin M, Street I, Adams TE, Johns TG. EGFRvIII-mediated transactivation of receptor tyrosine kinases in glioma: mechanism and therapeutic implications. Oncogene 2015; 34:5277-87. [PMID: 25659577 DOI: 10.1038/onc.2014.448] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2014] [Revised: 10/19/2014] [Accepted: 11/08/2014] [Indexed: 12/20/2022]
Abstract
A truncation mutant of the epidermal growth factor receptor, EGFRvIII, is commonly expressed in glioma, an incurable brain cancer. EGFRvIII is tumorigenic, in part, through its transactivation of other receptor tyrosine kinases (RTKs). Preventing the effects of this transactivation could form part of an effective therapy for glioma; however, the mechanism by which the transactivation occurs is unknown. Focusing on the RTK MET, we show that MET transactivation in U87MG human glioma cells in vitro is proportional to EGFRvIII activity and involves MET heterodimerization associated with a focal adhesion kinase (FAK) scaffold. The transactivation of certain other RTKs was, however, independent of FAK. Simultaneously targeting EGFRvIII (with panitumumab) and the transactivated RTKs themselves (with motesanib) in an intracranial mouse model of glioma resulted in significantly greater survival than with either agent alone, indicating that cotargeting these RTKs has potent antitumor efficacy and providing a strategy for treating EGFRvIII-expressing gliomas, which are usually refractory to treatment.
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Affiliation(s)
- S A Greenall
- Oncogenic Signalling Laboratory and Brain Cancer Discovery Collaborative, Centre for Cancer Research, MIMR-PHI Institute of Medical Research, Clayton, VIC, Australia.,Monash University, Clayton, VIC, Australia.,Division of Materials Science and Engineering, Commonwealth Scientific and Industrial Research Organisation, Parkville, VIC, Australia
| | - J F Donoghue
- Oncogenic Signalling Laboratory and Brain Cancer Discovery Collaborative, Centre for Cancer Research, MIMR-PHI Institute of Medical Research, Clayton, VIC, Australia.,Monash University, Clayton, VIC, Australia
| | - M Van Sinderen
- Oncogenic Signalling Laboratory and Brain Cancer Discovery Collaborative, Centre for Cancer Research, MIMR-PHI Institute of Medical Research, Clayton, VIC, Australia.,Monash University, Clayton, VIC, Australia
| | - V Dubljevic
- Oncogenic Signalling Laboratory and Brain Cancer Discovery Collaborative, Centre for Cancer Research, MIMR-PHI Institute of Medical Research, Clayton, VIC, Australia.,Monash University, Clayton, VIC, Australia
| | - S Budiman
- Oncogenic Signalling Laboratory and Brain Cancer Discovery Collaborative, Centre for Cancer Research, MIMR-PHI Institute of Medical Research, Clayton, VIC, Australia.,Monash University, Clayton, VIC, Australia
| | - M Devlin
- Peter MacCallum Cancer Centre, St Andrews Place, East Melbourne, VIC, Australia
| | - I Street
- CRC for Cancer Therapeutics, Bundoora, VIC, Australia.,The Walter and Eliza Hall Institute of Medical Research, Parkville, VIC, Australia.,Department of Medical Biology, University of Melbourne, Parkville, VIC, Australia
| | - T E Adams
- Division of Materials Science and Engineering, Commonwealth Scientific and Industrial Research Organisation, Parkville, VIC, Australia
| | - T G Johns
- Oncogenic Signalling Laboratory and Brain Cancer Discovery Collaborative, Centre for Cancer Research, MIMR-PHI Institute of Medical Research, Clayton, VIC, Australia.,Monash University, Clayton, VIC, Australia
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30
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Greenall SA, Donoghue JF, Gottardo NG, Johns TG, Adams TE. Glioma-specific Domain IV EGFR cysteine mutations promote ligand-induced covalent receptor dimerization and display enhanced sensitivity to dacomitinib in vivo. Oncogene 2014; 34:1658-66. [PMID: 24747966 DOI: 10.1038/onc.2014.106] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2013] [Revised: 03/03/2014] [Accepted: 03/12/2014] [Indexed: 01/15/2023]
Abstract
A feature of many gliomas is the amplification of the epidermal growth factor receptor (EGFR), resulting in its overexpression. Missense mutations or deletions within the extracellular domain are associated with this amplification and can lead to constitutive activation of the receptor, with the Domain I/II deletion, EGFRvIII, being the most common. These changes have also been associated with increased sensitivity to EGFR inhibition using small molecule inhibitors. We have expressed, in human glioma cells, EGFR containing four glioma-specific EGFR missense mutations within Domain IV (C620Y, C624F, C628Y and C636Y) to analyze their biological properties and sensitivity to EGFR inhibition. One of these mutants, C620Y, exhibited an enhanced basal phosphorylation, which was partially dependent on an EGFR-ligand autocrine loop. All Domain IV mutants responded equally as well as wildtype EGFR (wtEGFR) to ligand stimulation. Biochemical analysis revealed that a pre-formed, disulfide-bonded dimer associated with these mutations was underglycosylated, inactive and cytoplasmically retained. Ligand stimulation resulted in the formation of a tyrosine-phosphorylated, disulfide-bonded dimer for all Domain IV mutants but not for wtEGFR. Following treatment with the next-generation, irreversible pan-ErbB inhibitor dacomitinib, the C620Y, C624F and EGFRvIII mutants were inactivated, covalently dimerized and were retained in the cytoplasm, resulting in cell-surface receptor loss and, for C620Y and C624F, decreased binding of EGF. Dacomitinib treatment significantly reduced the in vivo growth of human glioma xenografts bearing C620Y, but not wtEGFR. Collectively, these data indicate that the unique biochemical traits of Domain IV EGFR cysteine mutants can be exploited for enhanced sensitivity to EGFR small molecule inhibitors, with potential clinical applications.
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Affiliation(s)
- S A Greenall
- 160;CSIRO Division of Materials Science and Engineering, Parkville, VIC, Australia
| | - J F Donoghue
- Oncogenic Signaling Laboratory and Brain Cancer Discovery Collaborative, Monash Institute of Medical Research, Clayton, VIC, Australia
| | - N G Gottardo
- Telethon Institute for Child Health Research and Brain Cancer Discovery Collaborative, Centre for Child Health Research, Subiaco, WA, Australia
| | - T G Johns
- Oncogenic Signaling Laboratory and Brain Cancer Discovery Collaborative, Monash Institute of Medical Research, Clayton, VIC, Australia
| | - T E Adams
- 160;CSIRO Division of Materials Science and Engineering, Parkville, VIC, Australia
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31
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Regulation of HGF expression by ΔEGFR-mediated c-Met activation in glioblastoma cells. Neoplasia 2013; 15:73-84. [PMID: 23359207 DOI: 10.1593/neo.121536] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2012] [Revised: 11/28/2012] [Accepted: 11/29/2012] [Indexed: 11/18/2022]
Abstract
The hepatocyte growth factor receptor (c-Met) and a constitutively active mutant of the epidermal growth factor receptor (ΔEGFR/EGFRvIII) are frequently overexpressed in glioblastoma (GBM) and promote tumorigenesis. The mechanisms underlying elevated hepatocyte growth factor (HGF) production in GBM are not understood. We found higher, coordinated mRNA expression levels of HGF and c-Met in mesenchymal (Mes) GBMs, a subtype associated with poor treatment response and shorter overall survival. In an HGF/c-Met-dependent GBM cell line, HGF expression declined upon silencing of c-Met using RNAi or by inhibiting its activity with SU11274. Silencing c-Met decreased anchorage-independent colony formation and increased the survival of mice bearing intracranial GBM xenografts. Consistent with these findings, c-Met activation by ΔEGFR also elevated HGF expression, and the inhibition of ΔEGFR with AG1478 reduced HGF levels. Interestingly, c-Met expression was required for ΔEGFR-mediated HGF production, anchorage-independent growth, and in vivo tumorigenicity, suggesting that these pathways are coupled. Using an unbiased mass spectrometry-based screen, we show that signal transducer and activator of transcription 3 (STAT3) Y705 is a downstream target of c-Met signaling. Suppression of STAT3 phosphorylation with WP1193 reduced HGF expression in ΔEGFR-expressing GBM cells, whereas constitutively active STAT3 partially rescued HGF expression and colony formation in c-Met knockdown cells expressing ΔEGFR. These results suggest that the c-Met/HGF signaling axis is enhanced by ΔEGFR through increased STAT3-dependent HGF expression and that targeting c-Met in Mes GBMs may be an important strategy for therapy.
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32
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Gan HK, Cvrljevic AN, Johns TG. The epidermal growth factor receptor variant III (EGFRvIII): where wild things are altered. FEBS J 2013; 280:5350-70. [DOI: 10.1111/febs.12393] [Citation(s) in RCA: 219] [Impact Index Per Article: 19.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2013] [Revised: 06/10/2013] [Accepted: 06/13/2013] [Indexed: 11/27/2022]
Affiliation(s)
- Hui K. Gan
- Tumour Targeting Program; Ludwig Institute for Cancer Research; Heidelberg Victoria Australia
| | - Anna N. Cvrljevic
- Oncogenic Signaling Laboratory; Monash University; Clayton Victoria Australia
| | - Terrance G. Johns
- Oncogenic Signaling Laboratory; Monash University; Clayton Victoria Australia
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33
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Kancha RK, von Bubnoff N, Duyster J. Asymmetric kinase dimer formation is crucial for the activation of oncogenic EGFRvIII but not for ERBB3 phosphorylation. Cell Commun Signal 2013; 11:39. [PMID: 23758840 PMCID: PMC3726407 DOI: 10.1186/1478-811x-11-39] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2012] [Accepted: 05/27/2013] [Indexed: 11/17/2022] Open
Abstract
Background Formation of asymmetric kinase dimers is required for wt-EGFR activation upon ligand stimulation. The role of receptor dimerization in oncogenic EGFRvIII mutant activation is not completely understood and the molecular details of EGFRvIII interactions within homo-dimers and hetero-dimers are not elucidated yet. Findings By employing mutations that disrupt the asymmetric kinase dimer interface in EGFRvIII, we demonstrate that the mechanism of oncogenic EGFRvIII mutant activation is similar to that of the full-length wild-type EGFR. Surprisingly, the monomeric EGFRvIII lacks autophosphorylation and the formation of asymmetric kinase dimers is indispensable for oncogenic kinase activation. In addition, we show that ERBB3 can act as an activator of EGFRvIII by forming asymmetric kinase dimer in a ligand-independent manner. Interestingly, we found that the formation of asymmetric kinase dimer is dispensable for ERBB3 phosphorylation by the activated EGFR kinase as well as the ERBB2 kinase thus revealing a novel model for receptor function. Conclusions Lateral signaling is a novel mechanism of signal propagation via ERBB3 upon activation by EGFR/ERBB2 kinase even in the absence of their ability to form asymmetric kinase dimers.
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Affiliation(s)
- Rama Krishna Kancha
- Department Medicine I, University Medical Center Freiburg, Freiburg, Germany
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34
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Hwang Y, Chumbalkar V, Latha K, Bogler O. Forced dimerization increases the activity of ΔEGFR/EGFRvIII and enhances its oncogenicity. Mol Cancer Res 2011; 9:1199-208. [PMID: 21775422 DOI: 10.1158/1541-7786.mcr-11-0229] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Delta epidermal growth factor receptor (ΔEGFR), an in-frame deletion mutant of the extracellular ligand-binding domain, which occurs in about 30% of glioblastoma, is a potent oncogene that promotes tumor growth and progression. The signaling of ΔEGFR is ligand-independent and low intensity, allowing it to evade the normal mechanisms of internalization and degradation by the endocytic machinery and hence is persistent. The basis of the oncogenic potential of ΔEGFR remains incompletely understood, including whether dimerization plays an important role in its signal and whether its oncogenic potential is dependent on its relatively low intensity, when compared with the acutely activated wild-type receptor. To examine these two important questions, we have generated a chimeric ΔEGFR that allows forced dimerization via domains derived from variants of the FKBP12 protein that are brought together by FK506 derivatives. Forced dimerization of chimeric ΔEGFR significantly increased the intensity of its signal, as measured by receptor phosphorylation levels, suggesting that the naturally occurring ΔEGFR does not form strong or stable dimers as part of its low level signal. Interestingly, the increased activity of dimerized, chimeric ΔEGFR did not promote receptor internalization, implying that reduced rate of endocytic downregulation of ΔEGFR is an inherent characteristic. Significantly, forced dimerization enhanced the oncogenic signal of the receptor, implying that the ΔEGFR is a potent oncogene despite, not because of its low intensity.
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Affiliation(s)
- Yeohyeon Hwang
- Department of Neurosurgery, University of Texas MD Anderson Cancer Center, 1515 Holcombe Blvd., Houston, TX 77030, USA
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