Award Number: W81XWH-10-1-0712 TITLE: Characterization of the Discoidin Domain Receptor 2 Kinase as a Novel Therapeutic Target for Squamous Cell Lung Cancer

authors’ affiliations: 1 Departments of Medical Oncology and 5 Biological Chemistry and Molecular Pharmacology, 18 Center for Cancer Genome Discovery, and Ludwig Center, Dana-Farber Cancer Institute, Boston; 4 Broad Institute, Cambridge, Massachusetts; 2 Max Planck Institute for Neurological Research, Klaus-Joachim-Zülch Laboratories of the Max Planck Society, and University of Köln Medical Faculty; 3 Department I of Internal Medicine and Laboratory of Translational Cancer Genomics, Center for Integrated Oncology Köln-Bonn, University of Köln; 9 Department I of Internal Medicine, Center for Integrated Oncology Köln-Bonn, University Hospital of Cologne; 15 Kliniken der Stadt Köln gGmbH, Cologne; 6 Chemical Genomics Center of the Max Planck Society and 19 Technical University Dortmund, Dortmund; 13 Department of Hematology/ Oncology, Jena University Hospital, Jena, Germany; 7 Department of Obstetrics and Gynecology, Haukeland University Hospital, and 8 Department of Clinical Medicine, University of Bergen, Bergen; 12 Division of Surgery and Cancer, Oslo University Hospital Radiumhospitalet, Oslo, Norway; 10 University Hospital Zurich, Zurich, Switzerland; 11 Institut Albert Bonniot, INSERM U823, Université Joseph Fourier, Grenoble, France; 14 Departments of Pulmonology and Pathology, University Medical Center Groningen and University of Groningen, Groningen, The Netherlands; 16 Section of Thoracic Surgery, Department of Surgery, University of Michigan Medical School, Ann Arbor, Michigan; 17 Ontario Cancer Institute and Princess Margaret Hospital, Toronto, Ontario, Canada; and 20 Departments of Thoracic Oncology and Experimental Therapeutics, H. Lee Moffitt Cancer Center and Research Institute, Tampa, Florida Although genomically targeted therapies have improved outcomes for patients with lung adenocarcinoma, little is known about the genomic alterations that drive squamous cell cancer (SCC) of the lung. Sanger sequencing of the tyrosine kinome identified mutations in the DDR2 kinase gene in 3.8% of lung SCCs and cell lines. Lung SCC cell lines harboring DDR2 mutations were selectively killed by knockdown of DDR2 by RNA interference or by treatment with the multitargeted kinase inhibitor dasatinib. Tumors established from a DDR2 mutant cell line were sensitive to dasatinib in xenograft models. Expression of mutated DDR2 led to cellular transformation that was blocked by dasatinib. A patient with lung SCC that responded to dasatinib and erlotinib treatment harbored a DDR2 kinase domain mutation. These data suggest that gain-of-function mutations in DDR2 are important oncogenic events and are amenable to therapy with dasatinib. Because dasatinib is already approved for use, these findings could be used to rapidly generate clinical trials. siGNificaNce: DDR2 mutations are present in 4% of lung SCCs, and DDR2 mutations are associated with sensitivity to dasatinib. These findings provide a rationale for designing clinical trials with the FDA-approved drug dasatinib in patients with lung SCCs. Cancer Discovery; 1(1). ©2011 AACR. cases and carries a grim prognosis; 70% of patients present with advanced and often incurable disease at the time of diagnosis ( 2 ). Despite these statistics, a great deal of progress has been made in the targeted treatment of patients with NSCLC, largely owing to the development of small-molecule inhibitors of the epidermal growth factor receptor (EGFR) tyrosine kinase ( 3–5 ). Patients who respond to EGFR kinase inhibitors are much more likely to have the adenocarcinoma subtype of NSCLC ( 6 ). Patients with the other principal subtype of NSCLC, lung squamous cell cancer (SCC), very rarely respond to these agents; few advances have been made in the treatment of this type of lung cancer, which accounts for 25% of NSCLC. In addition to EGFR, several other promising therapeutic targets have been identified in the laboratory, including EML4-ALK, KRAS, and MET; drugs directed against these proteins are being tested in clinical trials ( 7–10 ). However, it appears that these targets are likely limited to adenocarcinomas as well. A recent report has suggested that targeting FGFR1 amplifications in SCC of the lung may be a promising therapeutic strategy, although fibroblast growth factor receptor inhibitors are not currently in clinical use for the treatment of lung cancer ( 11 ). Given the burden of disease from lung SCC, we sought to identify new therapeutic targets by examining the tyrosine kinome of lung SCCs for novel mutated kinases. In this article, we report the identification of novel somatic mutations in the discoidin domain receptor 2 ( DDR2 ) tyrosine kinase gene at a frequency of 3.8% ( n = 11) in a sample set of 290 lung SCC samples. DDR2, a receptor tyrosine kinase that binds collagen as its endogenous ligand, has been previously shown to promote cell migration, proliferation, and survival when activated by ligand binding and phosphorylation ( 12–18 ). DDR1 and DDR2 mutations have been noted in several cancer specimens, including 4 DDR1 mutations (W385C, A496S, F866Y, and F824W) and 2 DDR2 mutations in lung cancer (R105S and N456S); these reports, however, have not been confirmed doi: 10.1158/2159-8274.CD-11-0005 *These authors contributed equally to this article. A. Dutt is currently affiliated with the Advanced Centre for Treatment, Research and Education in Cancer, Kharghar, Navi Mumbai, India Note: Supplementary data for this article are available at Cancer Discovery Online ( http://www.aacrjournals.org ). corresponding authors: Matthew Meyerson, Dana-Farber Cancer Institute, 450 Brookline Avenue, Boston, MA 02215. Phone: 617-632-4768; Fax: 617-582-7880; E-mail: Matthew_meyerson@dfci.harvard. edu; Roman Thomas, Max Planck Institute of Neurobiology, Gleueler Strasse 50, 50931 Cologne, Germany. E-mail: nini@nf.mpg. de; and Eric Haura, H. Lee Moffitt Cancer Center, 12902 Magnolia Drive, Tampa, FL 33612. E-mail: Eric.Haura@moffitt.org ©2011 American Association for Cancer Research. CANCER DISCOVERY. 2011; 1(1) doi: 10.1158/2159-8274.CD-11-0005 | OF77 INTRODUCTION Lung cancer is the leading cause of cancer-related mortality in the United States, with >157,000 deaths projected in 2010 ( 1 ). The more common type of lung cancer, non–small-cell lung cancer (NSCLC), accounts for 85% of