HPV-16 E6 and E7 genes, like SV40 early region genes, are insufficient for immortalization of human mesothelial and bronchial epithelial cells

Exp Cell Res. 1994 Aug;213(2):418-27. doi: 10.1006/excr.1994.1218.


Simian virus 40 (SV40)-transformed human cells usually have a period of increased proliferative potential that terminates in culture crisis, after which immortalization may or may not occur. This study addresses the question of whether human papillomavirus (HPV)-transformed cells may also undergo crisis. Two types of human epithelial cells were transfected with either HPV-16 E6 and E7 genes or SV40 early region genes, and all transfectants underwent at least 20 more population doublings than the normal cells from which they were derived. Mesothelial cells expressing SV40 or HPV-16 genes mostly entered crisis (4/4 SV40- and 3/4 HPV-transfected clones). Similarly, 1/3 SV40- and 2/3 HPV-transfected bronchial epithelial cell cultures entered crisis. For these two types of epithelial cells, we therefore conclude that HPV-16 E6 and E7 genes, like the SV40 T proteins, are insufficient for immortalization.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Bronchi / cytology
  • Cell Division
  • Cell Line
  • Cell Survival
  • Cell Transformation, Viral / genetics*
  • Epithelial Cells
  • Genes, Viral
  • Humans
  • Immediate-Early Proteins / genetics*
  • Immunohistochemistry
  • Oncogene Proteins, Viral / genetics*
  • Papillomaviridae / genetics*
  • Papillomavirus E7 Proteins
  • Repressor Proteins*
  • Simian virus 40 / genetics*
  • Transfection


  • E6 protein, Human papillomavirus type 16
  • Immediate-Early Proteins
  • Oncogene Proteins, Viral
  • Papillomavirus E7 Proteins
  • Repressor Proteins
  • oncogene protein E7, Human papillomavirus type 16