HPV16E6-dependent c-fos expression contributes to AP-1 complex formation in SiHa cells

Mediators Inflamm. 2011:2011:263216. doi: 10.1155/2011/263216. Epub 2011 Jul 31.

Abstract

To date, the major role of HPV16E6 in cancer has been considered to be its ability to inhibit the p53 tumor-suppressor protein, thereby thwarting p53-mediated cytotoxic responses to cellular stress signals. Here, we show that HPV16E6-dependent c-fos oncogenic protein expression contributes to AP-1 complex formation under oxidative stress in SiHa cells (HPV16-positive squamous cell carcinoma of the cervix). In addition, we examined the role of HPV16E6 in TGF-α-induced c-fos expression and found that the c-fos protein expression induced by TGF-α is HPV16E6 dependent. Thus, our results provide the first evidence that HPV16E6 contributes to AP-1 complex formation after both ligand-dependent and independent EGFR activation, suggesting a new therapeutic approach to the treatment of HPV-associated tumors.

MeSH terms

  • Cell Line, Tumor
  • Female
  • Gene Expression Regulation, Neoplastic
  • Humans
  • Oncogene Proteins, Viral / genetics
  • Oncogene Proteins, Viral / metabolism*
  • Proto-Oncogene Proteins c-fos / genetics
  • Proto-Oncogene Proteins c-fos / metabolism*
  • RNA, Small Interfering / genetics
  • RNA, Small Interfering / metabolism
  • Repressor Proteins / genetics
  • Repressor Proteins / metabolism*
  • Transcription Factor AP-1 / genetics
  • Transcription Factor AP-1 / metabolism*
  • Transforming Growth Factor alpha / metabolism
  • Uterine Cervical Neoplasms / metabolism
  • Uterine Cervical Neoplasms / pathology
  • Uterine Cervical Neoplasms / virology

Substances

  • E6 protein, Human papillomavirus type 16
  • Oncogene Proteins, Viral
  • Proto-Oncogene Proteins c-fos
  • RNA, Small Interfering
  • Repressor Proteins
  • Transcription Factor AP-1
  • Transforming Growth Factor alpha