Studies on the inhibition of feline EGFR in squamous cell carcinoma: enhancement of radiosensitivity and rescue of resistance to small molecule inhibitors

Cancer Biol Ther. 2011 Jun 1;11(11):927-37. doi: 10.4161/cbt.11.11.15525. Epub 2011 Jun 1.

Abstract

This study investigated different methods of EGFR (Epithelial Growth Factor Receptor) targeting in feline squamous cell carcinoma with the ultimate aim of establishing a large animal model of human head and neck cancer. Both small molecule receptor tyrosine kinase inhibitor (TKI) and RNA interference (RNAi) techniques were employed to target the feline EGFR. We demonstrated that the human drug gefitinib caused a reduction in cell proliferation and migration in a feline cell line. However, we also document the development of resistance that was not associated with mutation in the kinase domain. RNAi caused a potent reduction in EGFR activity and was able to overcome acquired gefitinib resistance. In addition, RNAi targeting of EGFR, but not gefitinib, caused an additive effect on cell killing when combined with radiation. These results support the use of feline SCC as a model of head and neck cancer in man in the search for novel and effective treatments for both tumors.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • Animals
  • Antineoplastic Agents / pharmacology*
  • Carcinoma, Squamous Cell / drug therapy*
  • Carcinoma, Squamous Cell / radiotherapy
  • Cats
  • Cell Line, Tumor
  • Cell Proliferation / drug effects
  • Combined Modality Therapy
  • Conserved Sequence
  • Disease Models, Animal
  • Drug Evaluation, Preclinical
  • Drug Resistance, Neoplasm / genetics*
  • ErbB Receptors / antagonists & inhibitors*
  • ErbB Receptors / genetics
  • Gefitinib
  • Head and Neck Neoplasms / drug therapy*
  • Head and Neck Neoplasms / radiotherapy
  • Humans
  • Quinazolines / pharmacology*
  • RNA Interference
  • Radiation Tolerance / genetics*
  • Signal Transduction

Substances

  • Antineoplastic Agents
  • Quinazolines
  • ErbB Receptors
  • Gefitinib