Antitumour efficacy of MEK inhibitors in human lung cancer cells and their derivatives with acquired resistance to different tyrosine kinase inhibitors

Br J Cancer. 2011 Jul 26;105(3):382-92. doi: 10.1038/bjc.2011.244. Epub 2011 Jul 12.

Abstract

Background: To study the molecular mechanisms regulating cancer cell resistance to four different tyrosine kinase inhibitors (TKIs): erlotinib, gefitinib, vandetanib and sorafenib.

Methods: An in vitro model of acquired resistance to these TKIs was developed by continuously treating the human lung adenocarcinoma cell line CALU-3 with escalating doses of each drug. Transcriptional profiling was performed with Agilent whole genome microarrays. Western blot analysis, enzyme-linked immunosorbent (ELISA), 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) cell proliferation, migration, invasion and anchorage-independent colony growth assays were conducted in vitro and experiments with established xenografts in athymic nude mice were performed in vivo in parental (P) and TKI-resistant (R) CALU-3 cell lines.

Results: As compared with P-CALU-3 cells, in TKI-R CALU-3 cell lines a significant increase in the expression of activated, phosphorylated MET, IGF-1R, AKT, MEK, MAPK and of survivin was observed. Downregulation of E-cadherin and amphiregulin mRNAs and upregulation of vimentin, VE-cadherin, HIF-1α and vascular endothelial growth factor receptor-1 mRNAs were observed in all four TKI-R CALU-3 cell lines. All four TKI-R CALU-3 cells showed increased invasion, migration and anchorage-independent growth. Together, these data suggest epithelial to mesenchymal transition (EMT) in TKI-R CALU-3 cells. Treatment with several agents that target AKT, MET or IGF-1R did not affect TKI-R CALU-3 cell proliferation. In contrast, treatment with MSC19363669B and selumetinib, two selective MEK inhibitors, caused inhibition of cell proliferation, invasion, migration, anchorage-independent growth in vitro and of tumour growth in vivo of all four TKI-R CALU-3 cell lines.

Conclusion: These data suggest that resistance to four different TKIs is characterised by EMT, which is MEK-inhibitor sensitive in human CALU-3 lung adenocarcinoma.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adenocarcinoma / drug therapy*
  • Adenocarcinoma of Lung
  • Animals
  • Benzenesulfonates / pharmacology
  • Cell Line, Tumor
  • Cell Proliferation / drug effects
  • Drug Resistance, Neoplasm*
  • Epithelial-Mesenchymal Transition / drug effects
  • Erlotinib Hydrochloride
  • Gefitinib
  • Gene Expression Profiling
  • Humans
  • Lung Neoplasms / drug therapy*
  • MAP Kinase Kinase Kinases / antagonists & inhibitors*
  • Mice
  • Mice, Nude
  • Niacinamide / analogs & derivatives
  • Phenylurea Compounds
  • Piperidines / pharmacology
  • Protein Kinase Inhibitors / therapeutic use*
  • Pyridines / pharmacology
  • Quinazolines / pharmacology
  • Sorafenib
  • Xenograft Model Antitumor Assays

Substances

  • Benzenesulfonates
  • Phenylurea Compounds
  • Piperidines
  • Protein Kinase Inhibitors
  • Pyridines
  • Quinazolines
  • Niacinamide
  • Sorafenib
  • Erlotinib Hydrochloride
  • MAP Kinase Kinase Kinases
  • Gefitinib
  • N-(4-bromo-2-fluorophenyl)-6-methoxy-7-((1-methylpiperidin-4-yl)methoxy)quinazolin-4-amine