Inhibition of epidermal growth factor receptor kinase induces protease-dependent apoptosis in human colon cancer cells

Gastroenterology. 1998 May;114(5):930-9. doi: 10.1016/s0016-5085(98)70312-9.


Background & aims: The epidermal growth factor receptor (EGFR) is under investigation as a therapeutic target for cancers. Colon cancer cell lines are variably dependent on autocrine stimulation of EGFR. We therefore examined the effects of a selective EGFR tyrosine kinase inhibitor, PD 153035, on proliferation and survival of five colon cancer cell lines whose autonomous proliferation is either EGFR ligand dependent or EGFR ligand independent.

Methods: Effects of inhibitors were screened by MTS growth assays, [3H]thymidine incorporation, terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick-end labeling assay, fluorescence microscopy, immunoblotting, and in vitro protease assays.

Results: PD 153035 caused dose-dependent cytostasis (200 nmol/L to 1 micromol/L) and apoptosis (>10 micromol/L) in ligand-dependent cell lines and caused variable apoptosis (>10 micromol/L) but no cytostasis in ligand-independent cell lines. Apoptosis induced by 10 micromol/L PD 153035 was not associated with induction of p53 protein expression but was accompanied by activation of caspases that cleave poly(ADP-ribose) polymerase, lamin B1, and Bcl-2. Inhibition of caspase 3-like protease activity by DEVD-fluoromethylketone significantly delayed the onset of PD 153035-induced apoptosis.

Conclusions: The EGFR tyrosine kinase inhibitor PD 153035 induces cytostasis and caspase-dependent apoptosis in EGFR ligand-dependent colon cancer cell lines. These observations encourage further investigation of EGFR tyrosine kinase inhibitors for treatment of colorectal neoplasms.

Publication types

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

MeSH terms

  • Apoptosis / drug effects
  • Apoptosis / physiology*
  • Colonic Neoplasms / pathology
  • Colonic Neoplasms / physiopathology*
  • Endopeptidases / physiology*
  • Enzyme Inhibitors / pharmacology
  • ErbB Receptors / metabolism*
  • Humans
  • Ligands
  • Protease Inhibitors / pharmacology
  • Protein-Tyrosine Kinases / antagonists & inhibitors*
  • Proto-Oncogene Proteins c-bcl-2 / metabolism
  • Quinazolines / pharmacology
  • Tumor Cells, Cultured / drug effects
  • Tumor Suppressor Protein p53 / metabolism


  • Enzyme Inhibitors
  • Ligands
  • Protease Inhibitors
  • Proto-Oncogene Proteins c-bcl-2
  • Quinazolines
  • Tumor Suppressor Protein p53
  • ErbB Receptors
  • Protein-Tyrosine Kinases
  • Endopeptidases
  • 4-((3-bromophenyl)amino)-6,7-dimethoxyquinazoline