title: Adaptive responses to dasatinib-treated lung squamous cell cancer cells harboring DDR2 mutations.
abstract: DDR2 mutations occur in approximately 4% of lung squamous cell cancer (SCC) where the tyrosine kinase inhibitor dasatinib has emerged as a new therapeutic option. We found that ERK and AKT phosphorylation was weakly inhibited by dasatinib in DDR2-mutant lung SCC cells, suggesting that dasatinib inhibits survival signals distinct from other oncogenic receptor tyrosine kinases (RTK) and/or compensatory signals exist that dampen dasatinib activity. To gain better insight into dasatinib's action in these cells, we assessed altered global tyrosine phosphorylation (pY) after dasatinib exposure using a mass spectrometry-based quantitative phosphoproteomics approach. Overlaying protein-protein interaction relationships upon this dasatinib-regulated pY network revealed decreased phosphorylation of Src family kinases and their targets. Conversely, dasatinib enhanced tyrosine phosphorylation in a panel of RTK and their signaling adaptor complexes, including EGFR, MET/GAB1, and IGF1R/IRS2, implicating a RTK-driven adaptive response associated with dasatinib. To address the significance of this observation, these results were further integrated with results from a small-molecule chemical library screen. We found that dasatinib combined with MET and insulin-like growth factor receptor (IGF1R) inhibitors had a synergistic effect, and ligand stimulation of EGFR and MET rescued DDR2-mutant lung SCC cells from dasatinib-induced loss of cell viability. Importantly, we observed high levels of tyrosine-phosphorylated EGFR and MET in a panel of human lung SCC tissues harboring DDR2 mutations. Our results highlight potential RTK-driven adaptive-resistant mechanisms upon DDR2 targeting, and they suggest new, rationale cotargeting strategies for DDR2-mutant lung SCC.
authors.affiliation: Department of Thoracic Oncology, H. Lee Moffitt Cancer Center and Research Institute, Tampa, FL 33612.
authors.forename: Yun
authors.initials: Y
authors.lastname: Bai
authors.affiliation: Department of Thoracic Oncology, H. Lee Moffitt Cancer Center and Research Institute, Tampa, FL 33612.
authors.forename: Jae-Young
authors.initials: JY
authors.lastname: Kim
authors.affiliation: Department of Drug Discovery, H. Lee Moffitt Cancer Center and Research Institute, Tampa, FL 33612.
authors.forename: January M
authors.initials: JM
authors.lastname: Watters
authors.affiliation: Proteomics Core Facility, H. Lee Moffitt Cancer Center and Research Institute, Tampa, FL 33612.
authors.forename: Bin
authors.initials: B
authors.lastname: Fang
authors.affiliation: Department of Thoracic Oncology, H. Lee Moffitt Cancer Center and Research Institute, Tampa, FL 33612.
authors.forename: Fumi
authors.initials: F
authors.lastname: Kinose
authors.affiliation: Department of Thoracic Oncology, H. Lee Moffitt Cancer Center and Research Institute, Tampa, FL 33612.
authors.forename: Lanxi
authors.initials: L
authors.lastname: Song
authors.affiliation: Department of Molecular Oncology, H. Lee Moffitt Cancer Center and Research Institute, Tampa, FL 33612.
authors.forename: John M
authors.initials: JM
authors.lastname: Koomen
authors.affiliation: Department of Biostatistics and Bioinformatics, H. Lee Moffitt Cancer Center and Research Institute, Tampa, FL 33612.
authors.forename: Jamie K
authors.initials: JK
authors.lastname: Teer
authors.affiliation: Department of Biostatistics and Bioinformatics, H. Lee Moffitt Cancer Center and Research Institute, Tampa, FL 33612.
authors.forename: Kate
authors.initials: K
authors.lastname: Fisher
authors.affiliation: Department of Biostatistics and Bioinformatics, H. Lee Moffitt Cancer Center and Research Institute, Tampa, FL 33612.
authors.forename: Yian Ann
authors.initials: YA
authors.lastname: Chen
authors.affiliation: Department of Drug Discovery, H. Lee Moffitt Cancer Center and Research Institute, Tampa, FL 33612.
authors.forename: Uwe
authors.initials: U
authors.lastname: Rix
authors.affiliation: Department of Thoracic Oncology, H. Lee Moffitt Cancer Center and Research Institute, Tampa, FL 33612.
authors.forename: Eric B
authors.initials: EB
authors.lastname: Haura
mesh_terms: D056704:Adaptive Immunity / Q000187:drug effects; D017209:Apoptosis / Q000187:drug effects; D045744:Cell Line, Tumor; D000069439:Dasatinib; D000070818:Discoidin Domain Receptors; D019008:Drug Resistance, Neoplasm / Q000235:genetics / Q000276:immunology; D004357:Drug Synergism; D006801:Humans; D008175:Lung Neoplasms / Q000188:drug therapy* / Q000276:immunology / Q000473:pathology; D009154:Mutation; D018307:Neoplasms, Squamous Cell / Q000188:drug therapy* / Q000276:immunology / Q000473:pathology; D051096:Proto-Oncogene Proteins c-ret / Q000378:metabolism; D011743:Pyrimidines / Q000008:administration & dosage*; D020794:Receptor Protein-Tyrosine Kinases / Q000235:genetics* / Q000378:metabolism; D011975:Receptors, Mitogen / Q000235:genetics* / Q000378:metabolism; D017451:Receptors, Somatomedin / Q000037:antagonists & inhibitors; D015398:Signal Transduction / Q000235:genetics; D013844:Thiazoles / Q000008:administration & dosage*
chemical_list: D011743:Pyrimidines; D011975:Receptors, Mitogen; D017451:Receptors, Somatomedin; D013844:Thiazoles; D000070818:Discoidin Domain Receptors; D051096:Proto-Oncogene Proteins c-ret; D020794:Receptor Protein-Tyrosine Kinases; D000069439:Dasatinib