MET amplification occurs with or without T790M mutations in EGFR mutant lung tumors with acquired resistance to gefitinib or erlotinib Academic Article uri icon

Overview

MeSH Major

  • Drug Resistance, Neoplasm
  • Gene Expression Regulation, Neoplastic
  • Lung Neoplasms
  • Mutation
  • Protein Kinase Inhibitors
  • Proto-Oncogene Proteins c-met
  • Quinazolines
  • Receptor, Epidermal Growth Factor

abstract

  • In human lung adenocarcinomas harboring EGFR mutations, a second-site point mutation that substitutes methionine for threonine at position 790 (T790M) is associated with approximately half of cases of acquired resistance to the EGFR kinase inhibitors, gefitinib and erlotinib. To identify other potential mechanisms that contribute to disease progression, we used array-based comparative genomic hybridization (aCGH) to compare genomic profiles of EGFR mutant tumors from untreated patients with those from patients with acquired resistance. Among three loci demonstrating recurrent copy number alterations (CNAs) specific to the acquired resistance set, one contained the MET proto-oncogene. Collectively, analysis of tumor samples from multiple independent patient cohorts revealed that MET was amplified in tumors from 9 of 43 (21%) patients with acquired resistance but in only two tumors from 62 untreated patients (3%) (P = 0.007, Fisher's Exact test). Among 10 resistant tumors from the nine patients with MET amplification, 4 also harbored the EGFR(T790M) mutation. We also found that an existing EGFR mutant lung adenocarcinoma cell line, NCI-H820, harbors MET amplification in addition to a drug-sensitive EGFR mutation and the T790M change. Growth inhibition studies demonstrate that these cells are resistant to both erlotinib and an irreversible EGFR inhibitor (CL-387,785) but sensitive to a multikinase inhibitor (XL880) with potent activity against MET. Taken together, these data suggest that MET amplification occurs independently of EGFR(T790M) mutations and that MET may be a clinically relevant therapeutic target for some patients with acquired resistance to gefitinib or erlotinib.

publication date

  • December 26, 2007

Research

keywords

  • Academic Article

Identity

Language

  • eng

PubMed Central ID

  • PMC2409244

Digital Object Identifier (DOI)

  • 10.1073/pnas.0710370104

PubMed ID

  • 18093943

Additional Document Info

start page

  • 20932

end page

  • 7

volume

  • 104

number

  • 52