Cigarette smoke induces genetic instability in airway epithelial cells by suppressing FANCD2 expression

Br J Cancer. 2008 May 20;98(10):1653-61. doi: 10.1038/sj.bjc.6604362. Epub 2008 May 13.

Abstract

Chromosomal abnormalities are commonly found in bronchogenic carcinoma cells, but the molecular causes of chromosomal instability (CIN) and their relationship to cigarette smoke has not been defined. Because the Fanconi anaemia (FA)/BRCA pathway is essential for maintenance of chromosomal stability, we tested the hypothesis that cigarette smoke suppresses that activity of this pathway. Here, we show that cigarette smoke condensate (CSC) inhibited translation of FANCD2 mRNA (but not FANCC or FANCG) in normal airway epithelial cells and that this suppression of FANCD2 expression was sufficient to induce both genetic instability and programmed cell death in the exposed cell population. Cigarette smoke condensate also suppressed FANCD2 function and induced CIN in bronchogenic carcinoma cells, but these cells were resistant to CSC-induced apoptosis relative to normal airway epithelial cells. We, therefore, suggest that CSC exerts pressure on airway epithelial cells that results in selection and emergence of genetically unstable somatic mutant clones that may have lost the capacity to effectively execute an apoptotic programme. Carcinogen-mediated suppression of FANCD2 gene expression provides a plausible molecular mechanism for CIN in bronchogenic carcinogenesis.

Publication types

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

MeSH terms

  • Apoptosis
  • Biomarkers, Tumor / genetics
  • Biomarkers, Tumor / metabolism*
  • Bronchial Neoplasms / genetics
  • Bronchial Neoplasms / metabolism*
  • Cell Survival
  • Chromosomal Instability*
  • Down-Regulation
  • Fanconi Anemia Complementation Group D2 Protein / genetics
  • Fanconi Anemia Complementation Group D2 Protein / metabolism*
  • Gene Expression Regulation, Neoplastic
  • Humans
  • Immunoblotting
  • RNA / metabolism
  • Respiratory Mucosa* / metabolism
  • Respiratory Mucosa* / pathology
  • Smoking / adverse effects*
  • Tobacco Smoke Pollution / adverse effects*

Substances

  • Biomarkers, Tumor
  • FANCD2 protein, human
  • Fanconi Anemia Complementation Group D2 Protein
  • Tobacco Smoke Pollution
  • RNA