title: Increased expression of 70 kD heat shock protein in cultured primary human keratinocytes induced by human papillomavirus 16 E6/E7 gene.
abstract: BACKGROUND
  Heat shock protein 70 (HSP70) is expressed highly in epithelial tumours associated closely with human papillomavirus 16 (HPV16) infections. However, evidence about the direct relationship between HSP70 expression and HPVs infections are still lacking. In the present study, we examined the expression of HSP70 in keratinocytes introduced with HPV16 E6/E7 oncogenes.
  
  
  METHODS
  Stable transfected cells were established by transfection of the plasmids pLXSN16E6/E7 into cultured primary keratinocytes and subsequently selected by plasmid specific selection antibiotic (G418) at the required concentration. The expression of HSP70 in pLXSN16E6/E7 transfected keratinocytes was determined by Western blot. The correlation of HSP70 expression and E6/E7 transfection was further confirmed by doubly labelled immunofluorescent staining.
  
  
  RESULTS
  Compared to non-transfected keratinocytes, there was a significant trend for higher levels of HSP70 in pLXSN16E6/E7 transfected keratinocytes. Doubly labelled immunofluorescent staining experiment showed that the co-localization of HPV16 E6/E7 and HSP70 in transfected keratinocytes was observed and increased expression of HSP70 was strongly associated with the transfection of HPV16 E6/E7.
  
  
  CONCLUSIONS
  Our studies demonstrated increased levels of HSP70 proteins in keratinocytes stably transfected by HPV16 E6/E7 oncogenes. It suggests that the expression of HSP70 is modulated by HPV16 E6/E7 proteins, which may be involved in HPV16 E6/E7 induced immortalization.
authors.affiliation: Department of Dermatology, Xijing Hospital, Fourth Military Medical University, Xi'an 710032, China. liaowenjun@263.net
authors.forename: Wen-jun
authors.initials: WJ
authors.lastname: Liao
authors.forename: Ping-shen
authors.initials: PS
authors.lastname: Fan
authors.forename: Meng
authors.initials: M
authors.lastname: Fu
authors.forename: Xue-li
authors.initials: XL
authors.lastname: Fan
authors.forename: Yu-feng
authors.initials: YF
authors.lastname: Liu
mesh_terms: D002478:Cells, Cultured; D050884:HSP72 Heat-Shock Proteins / Q000096:biosynthesis*; D006801:Humans; D015603:Keratinocytes / Q000378:metabolism*; D009856:Oncogene Proteins, Viral / Q000235:genetics*; D050725:Papillomavirus E7 Proteins; D012097:Repressor Proteins / Q000235:genetics*; D014162:Transfection
chemical_list: C068651:E6 protein, Human papillomavirus type 16; D050884:HSP72 Heat-Shock Proteins; D009856:Oncogene Proteins, Viral; D050725:Papillomavirus E7 Proteins; D012097:Repressor Proteins; C059731:oncogene protein E7, Human papillomavirus type 16