title: Simultaneous β1 integrin-EGFR targeting and radiosensitization of human head and neck cancer.
abstract: BACKGROUND
  Signaling from integrins and receptor tyrosine kinases (RTKs) contributes substantially to therapy resistance of malignant tumors. We investigated simultaneous β1 integrin-epidermal growth factor receptor (EGFR) targeting plus radiotherapy in human head and neck squamous cell carcinomas (HNSCCs).
  
  
  METHODS
  Ten HNSCC cell lines were grown in three-dimensional laminin-rich extracellular matrix cell cultures and two of them as tumor xenografts in nude mice (n = 12-16 per group). Targeting of β1 integrin and EGFR with monoclonal inhibitory antibodies (AIIB2 and cetuximab, respectively) was combined with x-ray irradiation. Clonogenic survival, tumor growth, and tumor control (evaluated by Kaplan-Meier analysis), apoptosis, phosphoproteome (interactome, network betweeness centrality analysis), receptor expression (immunohistochemistry), and downstream signaling (western blotting) were assessed. Various mutants of the integrin signaling mediator focal adhesion kinase (FAK) were employed for mechanistic studies. All statistical tests were two-sided.
  
  
  RESULTS
  Compared with β1 integrin or EGFR single inhibition, combined β1 integrin-EGFR targeting resulted in enhanced cytotoxicity and radiosensitization in eight out of 10 tested HNSCC cell lines, which responded with an FAK dephosphorylation after β1 integrin inhibition. In vivo, simultaneous anti-β1 integrin/anti-EGFR treatment and radiotherapy of UTSCC15 responder xenografts enabled better tumor control compared with anti-EGFR monotherapy and irradiation (hazard ratio [HR] = 6.9, 95% confidence interval [CI] = 1.6 to 30.9, P = .01), in contrast to the SAS nonresponder tumor model (HR = 0.9, 95% CI = 0.4 to 2.3, P = .83). Mechanistically, a protein complex consisting of FAK- and Erk1-mediated prosurvival signals for radiation resistance, which was effectively compromised by β1 integrin and EGFR blocking.
  
  
  CONCLUSIONS
  Concomitant targeting of β1 integrin and EGFR seems a powerful and promising approach to overcome radioresistance of HNSCCs.
authors: OncoRay, National Center for Radiation Research in Oncology, Faculty of Medicine and University Hospital Carl Gustav Carus, Technische Universität Dresden, Dresden, Germany and Helmholtz-Zentrum Dresden, Rossendorf, Dresden, Germany (IE, KZ, ED, LH, EM, MK, NC); Department of Radiation Oncology, University Hospital Carl Gustav Carus, Technische Universität Dresden, Germany (IE, MK, NC); Institute of Radiopharmaceutical Cancer Research, Helmholtz-Zentrum Dresden, Rossendorf, Dresden, Germany (KZ); Research Unit Radiation Cytogenetics, Helmholtz-Zentrum München, German Research Center for Environmental Health, Neuherberg, Germany (KU); Clinical Cooperation Group "Personalized Radiotherapy in Head and Neck Cancer," Helmholtz-Zentrum München, Neuherberg, Germany (KU); German Cancer Consortium (DKTK), Dresden, Germany, and German Cancer Research Center (DKFZ), Heidelberg, Germany (MK, NC); Institute of Radiooncology, Helmholtz-Zentrum Dresden, Rossendorf, Dresden, Germany (MK, NC).
authors: Iris
authors: I
authors: Eke
authors: OncoRay, National Center for Radiation Research in Oncology, Faculty of Medicine and University Hospital Carl Gustav Carus, Technische Universität Dresden, Dresden, Germany and Helmholtz-Zentrum Dresden, Rossendorf, Dresden, Germany (IE, KZ, ED, LH, EM, MK, NC); Department of Radiation Oncology, University Hospital Carl Gustav Carus, Technische Universität Dresden, Germany (IE, MK, NC); Institute of Radiopharmaceutical Cancer Research, Helmholtz-Zentrum Dresden, Rossendorf, Dresden, Germany (KZ); Research Unit Radiation Cytogenetics, Helmholtz-Zentrum München, German Research Center for Environmental Health, Neuherberg, Germany (KU); Clinical Cooperation Group "Personalized Radiotherapy in Head and Neck Cancer," Helmholtz-Zentrum München, Neuherberg, Germany (KU); German Cancer Consortium (DKTK), Dresden, Germany, and German Cancer Research Center (DKFZ), Heidelberg, Germany (MK, NC); Institute of Radiooncology, Helmholtz-Zentrum Dresden, Rossendorf, Dresden, Germany (MK, NC).
authors: Katja
authors: K
authors: Zscheppang
authors: OncoRay, National Center for Radiation Research in Oncology, Faculty of Medicine and University Hospital Carl Gustav Carus, Technische Universität Dresden, Dresden, Germany and Helmholtz-Zentrum Dresden, Rossendorf, Dresden, Germany (IE, KZ, ED, LH, EM, MK, NC); Department of Radiation Oncology, University Hospital Carl Gustav Carus, Technische Universität Dresden, Germany (IE, MK, NC); Institute of Radiopharmaceutical Cancer Research, Helmholtz-Zentrum Dresden, Rossendorf, Dresden, Germany (KZ); Research Unit Radiation Cytogenetics, Helmholtz-Zentrum München, German Research Center for Environmental Health, Neuherberg, Germany (KU); Clinical Cooperation Group "Personalized Radiotherapy in Head and Neck Cancer," Helmholtz-Zentrum München, Neuherberg, Germany (KU); German Cancer Consortium (DKTK), Dresden, Germany, and German Cancer Research Center (DKFZ), Heidelberg, Germany (MK, NC); Institute of Radiooncology, Helmholtz-Zentrum Dresden, Rossendorf, Dresden, Germany (MK, NC).
authors: Ellen
authors: E
authors: Dickreuter
authors: OncoRay, National Center for Radiation Research in Oncology, Faculty of Medicine and University Hospital Carl Gustav Carus, Technische Universität Dresden, Dresden, Germany and Helmholtz-Zentrum Dresden, Rossendorf, Dresden, Germany (IE, KZ, ED, LH, EM, MK, NC); Department of Radiation Oncology, University Hospital Carl Gustav Carus, Technische Universität Dresden, Germany (IE, MK, NC); Institute of Radiopharmaceutical Cancer Research, Helmholtz-Zentrum Dresden, Rossendorf, Dresden, Germany (KZ); Research Unit Radiation Cytogenetics, Helmholtz-Zentrum München, German Research Center for Environmental Health, Neuherberg, Germany (KU); Clinical Cooperation Group "Personalized Radiotherapy in Head and Neck Cancer," Helmholtz-Zentrum München, Neuherberg, Germany (KU); German Cancer Consortium (DKTK), Dresden, Germany, and German Cancer Research Center (DKFZ), Heidelberg, Germany (MK, NC); Institute of Radiooncology, Helmholtz-Zentrum Dresden, Rossendorf, Dresden, Germany (MK, NC).
authors: Linda
authors: L
authors: Hickmann
authors: OncoRay, National Center for Radiation Research in Oncology, Faculty of Medicine and University Hospital Carl Gustav Carus, Technische Universität Dresden, Dresden, Germany and Helmholtz-Zentrum Dresden, Rossendorf, Dresden, Germany (IE, KZ, ED, LH, EM, MK, NC); Department of Radiation Oncology, University Hospital Carl Gustav Carus, Technische Universität Dresden, Germany (IE, MK, NC); Institute of Radiopharmaceutical Cancer Research, Helmholtz-Zentrum Dresden, Rossendorf, Dresden, Germany (KZ); Research Unit Radiation Cytogenetics, Helmholtz-Zentrum München, German Research Center for Environmental Health, Neuherberg, Germany (KU); Clinical Cooperation Group "Personalized Radiotherapy in Head and Neck Cancer," Helmholtz-Zentrum München, Neuherberg, Germany (KU); German Cancer Consortium (DKTK), Dresden, Germany, and German Cancer Research Center (DKFZ), Heidelberg, Germany (MK, NC); Institute of Radiooncology, Helmholtz-Zentrum Dresden, Rossendorf, Dresden, Germany (MK, NC).
authors: Ercole
authors: E
authors: Mazzeo
authors: OncoRay, National Center for Radiation Research in Oncology, Faculty of Medicine and University Hospital Carl Gustav Carus, Technische Universität Dresden, Dresden, Germany and Helmholtz-Zentrum Dresden, Rossendorf, Dresden, Germany (IE, KZ, ED, LH, EM, MK, NC); Department of Radiation Oncology, University Hospital Carl Gustav Carus, Technische Universität Dresden, Germany (IE, MK, NC); Institute of Radiopharmaceutical Cancer Research, Helmholtz-Zentrum Dresden, Rossendorf, Dresden, Germany (KZ); Research Unit Radiation Cytogenetics, Helmholtz-Zentrum München, German Research Center for Environmental Health, Neuherberg, Germany (KU); Clinical Cooperation Group "Personalized Radiotherapy in Head and Neck Cancer," Helmholtz-Zentrum München, Neuherberg, Germany (KU); German Cancer Consortium (DKTK), Dresden, Germany, and German Cancer Research Center (DKFZ), Heidelberg, Germany (MK, NC); Institute of Radiooncology, Helmholtz-Zentrum Dresden, Rossendorf, Dresden, Germany (MK, NC).
authors: Kristian
authors: K
authors: Unger
authors: OncoRay, National Center for Radiation Research in Oncology, Faculty of Medicine and University Hospital Carl Gustav Carus, Technische Universität Dresden, Dresden, Germany and Helmholtz-Zentrum Dresden, Rossendorf, Dresden, Germany (IE, KZ, ED, LH, EM, MK, NC); Department of Radiation Oncology, University Hospital Carl Gustav Carus, Technische Universität Dresden, Germany (IE, MK, NC); Institute of Radiopharmaceutical Cancer Research, Helmholtz-Zentrum Dresden, Rossendorf, Dresden, Germany (KZ); Research Unit Radiation Cytogenetics, Helmholtz-Zentrum München, German Research Center for Environmental Health, Neuherberg, Germany (KU); Clinical Cooperation Group "Personalized Radiotherapy in Head and Neck Cancer," Helmholtz-Zentrum München, Neuherberg, Germany (KU); German Cancer Consortium (DKTK), Dresden, Germany, and German Cancer Research Center (DKFZ), Heidelberg, Germany (MK, NC); Institute of Radiooncology, Helmholtz-Zentrum Dresden, Rossendorf, Dresden, Germany (MK, NC).
authors: Mechthild
authors: M
authors: Krause
authors: OncoRay, National Center for Radiation Research in Oncology, Faculty of Medicine and University Hospital Carl Gustav Carus, Technische Universität Dresden, Dresden, Germany and Helmholtz-Zentrum Dresden, Rossendorf, Dresden, Germany (IE, KZ, ED, LH, EM, MK, NC); Department of Radiation Oncology, University Hospital Carl Gustav Carus, Technische Universität Dresden, Germany (IE, MK, NC); Institute of Radiopharmaceutical Cancer Research, Helmholtz-Zentrum Dresden, Rossendorf, Dresden, Germany (KZ); Research Unit Radiation Cytogenetics, Helmholtz-Zentrum München, German Research Center for Environmental Health, Neuherberg, Germany (KU); Clinical Cooperation Group "Personalized Radiotherapy in Head and Neck Cancer," Helmholtz-Zentrum München, Neuherberg, Germany (KU); German Cancer Consortium (DKTK), Dresden, Germany, and German Cancer Research Center (DKFZ), Heidelberg, Germany (MK, NC); Institute of Radiooncology, Helmholtz-Zentrum Dresden, Rossendorf, Dresden, Germany (MK, NC). nils.cordes@oncoray.de.
authors: Nils
authors: N
authors: Cordes
mesh_terms: D000818:Animals; D000911:Antibodies, Monoclonal / Q000494:pharmacology* / Q000627:therapeutic use; D061067:Antibodies, Monoclonal, Humanized / Q000008:administration & dosage / Q000494:pharmacology; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000494:pharmacology* / Q000627:therapeutic use; D017209:Apoptosis; D015153:Blotting, Western; D002294:Carcinoma, Squamous Cell / Q000188:drug therapy / Q000532:radiotherapy / Q000628:therapy*; D045744:Cell Line, Tumor; D000068818:Cetuximab; D066246:ErbB Receptors / Q000037:antagonists & inhibitors*; D051417:Focal Adhesion Kinase 1 / Q000378:metabolism; D015972:Gene Expression Regulation, Neoplastic / Q000187:drug effects; D006258:Head and Neck Neoplasms / Q000188:drug therapy / Q000532:radiotherapy / Q000628:therapy*; D006801:Humans; D007150:Immunohistochemistry; D019012:Integrin beta1 / Q000187:drug effects*; D053208:Kaplan-Meier Estimate; D051379:Mice; D008819:Mice, Nude; D048052:Mitogen-Activated Protein Kinase 3 / Q000378:metabolism; D058990:Molecular Targeted Therapy / Q000379:methods*; D016017:Odds Ratio; D011838:Radiation-Sensitizing Agents / Q000627:therapeutic use; D015398:Signal Transduction; D000077195:Squamous Cell Carcinoma of Head and Neck; D023041:Xenograft Model Antitumor Assays
chemical_list: D000911:Antibodies, Monoclonal; D061067:Antibodies, Monoclonal, Humanized; D019012:Integrin beta1; D011838:Radiation-Sensitizing Agents; C512478:EGFR protein, human; D066246:ErbB Receptors; D051417:Focal Adhesion Kinase 1; C496050:PTK2 protein, human; D048052:Mitogen-Activated Protein Kinase 3; D000068818:Cetuximab