RRC ID 6791
Author Bachleitner-Hofmann T, Sun MY, Chen CT, Tang L, Song L, Zeng Z, Shah M, Christensen JG, Rosen N, Solit DB, Weiser MR.
Title HER kinase activation confers resistance to MET tyrosine kinase inhibition in MET oncogene-addicted gastric cancer cells.
Journal Mol Cancer Ther
Abstract Tumor cells with genomic amplification of MET display constitutive activation of the MET tyrosine kinase, which renders them highly sensitive to MET inhibition. Several MET inhibitors have recently entered clinical trials; however, as with other molecularly targeted agents, resistance is likely to develop. Therefore, elucidating possible mechanisms of resistance is of clinical interest. We hypothesized that collateral growth factor receptor pathway activation can overcome the effects of MET inhibition in MET-amplified cancer cells by reactivating key survival pathways. Treatment of MET-amplified GTL-16 and MKN-45 gastric cancer cells with the highly selective MET inhibitor PHA-665752 abrogated MEK/mitogen-activated protein kinase (MAPK) and phosphoinositide 3-kinase (PI3K)/AKT signaling, resulting in cyclin D1 loss and G(1) arrest. PHA-665752 also inhibited baseline phosphorylation of epidermal growth factor receptor (EGFR) and HER-3, which are transactivated via MET-driven receptor cross-talk in these cells. However, MET-independent HER kinase activation using EGF (which binds to and activates EGFR) or heregulin-beta1 (which binds to and activates HER-3) was able to overcome the growth-inhibitory effects of MET inhibition by restimulating MEK/MAPK and/or PI3K/AKT signaling, suggesting a possible escape mechanism. Importantly, dual inhibition of MET and HER kinase signaling using PHA-665752 in combination with the EGFR inhibitor gefitinib or in combination with inhibitors of MEK and AKT prevented the above rescue effects. Our results illustrate that highly targeted MET tyrosine kinase inhibition leaves MET oncogene-"addicted" cancer cells vulnerable to HER kinase-mediated reactivation of the MEK/MAPK and PI3K/AKT pathways, providing a rationale for combined inhibition of MET and HER kinase signaling in MET-amplified tumors that coexpress EGFR and/or HER-3.
Volume 7(11)
Pages 3499-508
Published 2008-11-1
DOI 10.1158/1535-7163.MCT-08-0374
PII 1535-7163.MCT-08-0374
PMID 18974395
MeSH Antineoplastic Agents / pharmacology* Antineoplastic Agents / therapeutic use Cell Line, Tumor Cell Proliferation Cyclin D1 / metabolism Drug Resistance, Neoplasm / drug effects Enzyme Activation ErbB Receptors / metabolism* Humans Indoles / pharmacology Indoles / therapeutic use Mitogen-Activated Protein Kinase Kinases / metabolism Phosphatidylinositol 3-Kinases / metabolism Phosphorylation Protein Kinase Inhibitors / pharmacology* Protein Kinase Inhibitors / therapeutic use Proto-Oncogene Proteins c-met / antagonists & inhibitors* Proto-Oncogene Proteins c-met / genetics Proto-Oncogene Proteins c-met / metabolism Receptor, ErbB-3 / metabolism* Signal Transduction Stomach Neoplasms / drug therapy* Stomach Neoplasms / enzymology* Sulfones / pharmacology Sulfones / therapeutic use Transfection
IF 5.615
Times Cited 93
Human and Animal Cells MKN45(RCB1001)