Stearoyl-CoA desaturase activity modulates the activation of epidermal growth factor receptor in human lung cancer cells

Exp Biol Med (Maywood). 2012 Sep;237(9):1007-17. doi: 10.1258/ebm.2012.012126. Epub 2012 Sep 3.

Abstract

Stearoyl-CoA desaturase-1 (SCD1), the main enzyme that converts saturated fatty acids into monounsaturated fatty acids, is a key factor in the mechanisms of cancer cell proliferation, survival and tumorigenesis. Evidence indicates that SCD1 activity regulates these events in part by targeting the phosphatidylinositol-3 phosphate kinase/Akt and Ras/extracellular signal-regulated kinase (ERK) pathways, but the molecular mechanisms remain unknown. We now show that in H460 lung cancer cells, the suppression of SCD activity with CVT-11127, a specific small molecule SCD inhibitor, impairs the ligand-induced phosphorylation of epidermal growth factor (EGF) receptor, causing the inactivation of its downstream targets Akt, ERK and mammalian target of rapamycin. Importantly, the mitogenic response to EGF was markedly defective in SCD-depleted cancer cells. The inactivation of EGF receptor (EGFR) promoted by SCD inhibition may be caused by perturbations in the lipid microenvironment surrounding the receptor, since we detected significant alterations in the lateral mobility of plasma lipid microdomains. Finally, incubation of lung cancer cells with SCD blockers potentiated the antigrowth effect of gefitinib, an EGFR inhibitor employed in cancer treatment. Altogether, our data indicate that SCD activity may control cancer cell metabolism, proliferation and survival by modulating the EGFR→Akt/ERK signaling platforms. Our studies also suggest a value for SCD inhibitors as novel pharmacological agents in lung cancer, one of the most common and lethal forms of cancer for which therapeutic options remain very limited.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Antineoplastic Agents / pharmacology
  • Cell Line, Tumor
  • Cell Proliferation
  • Cell Survival
  • Cell Transformation, Neoplastic
  • ErbB Receptors / antagonists & inhibitors
  • ErbB Receptors / metabolism*
  • Extracellular Signal-Regulated MAP Kinases / antagonists & inhibitors
  • Extracellular Signal-Regulated MAP Kinases / metabolism
  • Gefitinib
  • Humans
  • Lung Neoplasms / enzymology
  • Lung Neoplasms / metabolism*
  • MAP Kinase Signaling System / drug effects
  • Phosphatidylinositol 3-Kinases / metabolism
  • Phosphoinositide-3 Kinase Inhibitors
  • Phosphorylation / drug effects
  • Proto-Oncogene Proteins c-akt / antagonists & inhibitors
  • Proto-Oncogene Proteins c-akt / metabolism
  • Quinazolines / pharmacology
  • Stearoyl-CoA Desaturase / antagonists & inhibitors
  • Stearoyl-CoA Desaturase / metabolism*
  • TOR Serine-Threonine Kinases / antagonists & inhibitors

Substances

  • Antineoplastic Agents
  • Phosphoinositide-3 Kinase Inhibitors
  • Quinazolines
  • Stearoyl-CoA Desaturase
  • MTOR protein, human
  • ErbB Receptors
  • Proto-Oncogene Proteins c-akt
  • TOR Serine-Threonine Kinases
  • Extracellular Signal-Regulated MAP Kinases
  • Gefitinib