Aneuploid human colonic epithelial cells are sensitive to AICAR-induced growth inhibition through EGFR degradation

Oncogene. 2013 Jun 27;32(26):3139-46. doi: 10.1038/onc.2012.339. Epub 2012 Aug 13.


Trisomy for chromosome 7 is frequently observed as an initiating event in sporadic colorectal cancer. Although unstable chromosome numbers and recurrent aneuploidies drive a large fraction of human cancers, targeted therapies selective to pre-neoplastic trisomic cells are non-existent. We have previously characterized a trisomy 7 cell line (1CT+7) spontaneously derived from normal diploid human colonic epithelial cells that aberrantly expresses the epidermal growth factor receptor (EGFR, chromosome 7p11). Recent studies identified AICAR (5-aminoimidazole-4-carboxamide-1-β-D-ribofuranoside) as a pharmacological inhibitor of aneuploid murine fibroblast proliferation. Here, we report that AICAR induces profound cytostatic and metabolic effects on 1CT+7 cells, but not on their isogenic diploid counterpart. Dose-response experiments indicate that 1CT+7 cells are fourfold preferentially sensitive to AICAR compared to diploid cells. Unexpectedly, treatment of 1CT+7 cells with AICAR led to a reversible 3.5-fold reduction (P=0.0025) in EGFR overexpression. AICAR-induced depletion of EGFR protein can be abrogated through inhibition of the proteasome with MG132. AICAR also heavily promoted EGFR ubiquitination in cell-based immunoprecipitation assays, suggesting enhanced degradation of EGFR protein mediated by the proteasome. Moreover, treatment with AICAR reduced EGFR protein levels in a panel of human colorectal cancer cells in vitro and in xenograft tumors in vivo. Our data collectively support the pharmacological compound AICAR as a novel inhibitor of EGFR protein abundance and as a potential anticancer agent for aneuploidy-driven colorectal cancer.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Aminoimidazole Carboxamide / analogs & derivatives*
  • Aminoimidazole Carboxamide / pharmacology
  • Aneuploidy
  • Animals
  • Antineoplastic Agents / pharmacology
  • Cell Line, Tumor
  • Cell Proliferation / drug effects
  • Colon / drug effects
  • Colon / metabolism
  • Colorectal Neoplasms / drug therapy*
  • Epithelial Cells / drug effects*
  • Epithelial Cells / metabolism
  • ErbB Receptors / metabolism*
  • Humans
  • Hypoglycemic Agents / pharmacology
  • Intestinal Mucosa / drug effects*
  • Intestinal Mucosa / metabolism
  • Leupeptins / pharmacology
  • Mice
  • Neoplasm Transplantation
  • Proteasome Endopeptidase Complex / metabolism
  • Ribonucleotides / pharmacology*
  • Transplantation, Heterologous
  • Trisomy
  • Ubiquitination


  • Antineoplastic Agents
  • Hypoglycemic Agents
  • Leupeptins
  • Ribonucleotides
  • Aminoimidazole Carboxamide
  • EGFR protein, human
  • ErbB Receptors
  • Proteasome Endopeptidase Complex
  • AICA ribonucleotide
  • benzyloxycarbonylleucyl-leucyl-leucine aldehyde