Cookies on this website
We use cookies to ensure that we give you the best experience on our website. If you click 'Continue' we'll assume that you are happy to receive all cookies and you won't see this message again. Click 'Find out more' for information on how to change your cookie settings.

PURPOSE: Conventional therapies for patients with lung cancer have reached a therapeutic plateau. We therefore evaluated the feasibility of combined vascular endothelial growth factor (VEGF) receptor 2 (VEGFR2) and epidermal growth factor (EGF) receptor (EGFR) targeting with radiation therapy in an orthotopic model that closely recapitulates the clinical presentation of human lung cancer. METHODS AND MATERIALS: Effects of irradiation and/or ZD6474, a small-molecule inhibitor of VEGFR2 and EGFR tyrosine kinases, were studied in vitro for human lung adenocarcinoma cells by using proliferation and clonogenic assays. The feasibility of combining ZD6474 with radiation therapy was then evaluated in an orthotopic model of human lung adenocarcinoma. Lung tumor burden and spread within the thorax were assessed, and tumor and adjacent tissues were analyzed by means of immunohistochemical staining for multiple parameters, including CD31, VEGF, VEGFR2, EGF, EGFR, matrix metalloproteinase-2 and -9, and basic fibroblast growth factor. RESULTS: ZD6474 enhanced the radioresponse of NCI-H441 human lung adenocarcinoma cells by a factor of 1.37 and markedly inhibited sublethal damage repair. In vivo, the combined blockade of VEGFR2 and EGFR by ZD6474 blocked pleural effusion formation and angiogenesis and enhanced the antivascular and antitumor effects of radiation therapy in the orthotopic human lung cancer model and was superior to chemoradiotherapy. CONCLUSIONS: When radiation therapy is combined with VEGFR2 and EGFR blockade, significant enhancement of antiangiogenic, antivascular, and antitumor effects are seen in an orthotopic model of lung cancer. These data provide support for clinical trials of biologically targeted and conventional therapies for human lung cancer.

Original publication

DOI

10.1016/j.ijrobp.2007.07.2350

Type

Journal article

Journal

Int J Radiat Oncol Biol Phys

Publication Date

01/12/2007

Volume

69

Pages

1534 - 1543

Keywords

Animals, Cell Line, Tumor, Cell Proliferation, Combined Modality Therapy, DNA Repair, Epidermal Growth Factor, ErbB Receptors, Feasibility Studies, Humans, Lung Neoplasms, Male, Mice, Mice, Nude, Neovascularization, Pathologic, Piperidines, Pleural Effusion, Quinazolines, Radiation Tolerance, Radiation-Sensitizing Agents, Receptors, Vascular Endothelial Growth Factor, Vascular Endothelial Growth Factor A, Vascular Endothelial Growth Factor Receptor-2, Xenograft Model Antitumor Assays