Long-lasting inhibition of EGFR autophosphorylation in A549 tumor cells by intracellular accumulation of non-covalent inhibitors

Bioorg Med Chem Lett. 2013 Oct 1;23(19):5290-4. doi: 10.1016/j.bmcl.2013.08.008. Epub 2013 Aug 11.

Abstract

In the present study, a small set of reversible or irreversible 4-anilinoquinazoline EGFR inhibitors was tested in A549 cells at early (1h) and late (8h) time points after inhibitor removal from culture medium. A combination of assays was employed to explain the observed long-lasting inhibition of EGFR autophosphorylation. We found that EGFR inhibition at 8h can be due, besides to the covalent interaction of the inhibitor with Cys797, as for PD168393 (2) and its prodrug 4, to the intracellular accumulation of non-covalent inhibitors by means of an active cell uptake, as for 5 and 6. Compounds 5-6 showed similar potency and duration of inhibition of EGFR autophosphorylation as the covalent inhibitor 2, while being devoid of reactive groups forming covalent bonds with protein thiols.

Keywords: A549 cell line; Active transport; EGFR; HPLC–MS/MS; Irreversible inhibitors.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Aniline Compounds / chemistry
  • Aniline Compounds / pharmacokinetics
  • Aniline Compounds / pharmacology
  • Cell Cycle Checkpoints / drug effects
  • Cell Line, Tumor
  • Chemistry, Pharmaceutical
  • ErbB Receptors / antagonists & inhibitors*
  • Humans
  • Inhibitory Concentration 50
  • Molecular Structure
  • Phosphorylation / drug effects
  • Quinazolines* / chemistry
  • Quinazolines* / pharmacokinetics
  • Quinazolines* / pharmacology
  • Time Factors

Substances

  • 6-hydroxypropynyl-4-anilinoquinazoline
  • Aniline Compounds
  • PD168393
  • Quinazolines
  • ErbB Receptors