The human papillomavirus type 16 E7 oncoprotein activates the Fanconi anemia (FA) pathway and causes accelerated chromosomal instability in FA cells

J Virol. 2007 Dec;81(23):13265-70. doi: 10.1128/JVI.01121-07. Epub 2007 Sep 26.

Abstract

Fanconi anemia (FA) patients have an increased risk for squamous cell carcinomas (SCCs) at sites of predilection for infection with high-risk human papillomavirus (HPV) types, including the oral cavity and the anogenital tract. We show here that activation of the FA pathway is a frequent event in cervical SCCs. We found that FA pathway activation is triggered mainly by the HPV type 16 (HPV-16) E7 oncoprotein and is associated with an enhanced formation of large FANCD2 foci and recruitment of FANCD2 as well as FANCD1/BRCA2 to chromatin. Episomal expression of HPV-16 oncoproteins was sufficient to activate the FA pathway. Importantly, the expression of HPV-16 E7 in FA-deficient cells led to accelerated chromosomal instability. Taken together, our findings establish the FA pathway as an early host cell response to high-risk HPV infection and may help to explain the greatly enhanced susceptibility of FA patients to squamous cell carcinogenesis at anatomic sites that are frequently infected by high-risk HPVs.

Publication types

  • Research Support, N.I.H., Extramural

MeSH terms

  • Apoptosis Regulatory Proteins
  • BRCA2 Protein / metabolism*
  • Cell Line
  • Chromatin / metabolism
  • Chromosomal Instability*
  • Fanconi Anemia Complementation Group D2 Protein / metabolism*
  • Human papillomavirus 16 / metabolism*
  • Humans
  • Oncogene Proteins, Viral / metabolism*
  • Papillomavirus E7 Proteins
  • Protein Binding

Substances

  • Apoptosis Regulatory Proteins
  • BLID protein, human
  • BRCA2 Protein
  • BRCA2 protein, human
  • Chromatin
  • FANCD2 protein, human
  • Fanconi Anemia Complementation Group D2 Protein
  • Oncogene Proteins, Viral
  • Papillomavirus E7 Proteins
  • oncogene protein E7, Human papillomavirus type 16