Human immunodeficiency virus type 1 tat gene enhances human papillomavirus early gene expression

Intervirology. 1993;36(2):57-64. doi: 10.1159/000150322.


To investigate the possible direct/indirect role of Human immunodeficiency virus (HIV) as a cofactor in human papillomavirus (HPV) oncogenesis, cotransfection experiments were carried out in which a recombinant plasmid containing the HPV16 long control region (LCR) linked to the chloramphenicol acetyltransferase (CAT) gene was cotransfected into cultured cells with a plasmid expressing HIV-1 Tat protein. Tat expression efficiency and transactivation activity were evaluated in different cell lines by cotransfecting plasmids containing the HIV tat gene and HIV LTR-driven CAT-coding sequences. HeLa and CaSki cell lines represented the most appropriate recipient cells for Tat-directed transactivation of both the HIV LTR and the HPV LCR promoters. Furthermore, HIV tat was transfected into HeLa cells (containing 10-20 copies per cell of HPV18), and HPV18 E7 protein expression was evaluated by a radioimmunoprecipitation assay using polyclonal antibodies against the E7 protein. Our results show that the Tat protein can transactivate the HPV LCR and increase HPV18 E7 expression in HeLa cells.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Gene Expression Regulation, Viral / genetics
  • Gene Expression Regulation, Viral / physiology*
  • Gene Products, tat / genetics
  • Gene Products, tat / physiology*
  • Genes, tat / physiology*
  • HeLa Cells
  • Humans
  • Oncogene Proteins, Viral / genetics
  • Papillomaviridae / genetics*
  • Papillomavirus E7 Proteins
  • Repressor Proteins*
  • Transcriptional Activation / genetics
  • Transcriptional Activation / physiology*
  • Transfection
  • Tumor Cells, Cultured


  • E6 protein, Human papillomavirus type 16
  • Gene Products, tat
  • Oncogene Proteins, Viral
  • Papillomavirus E7 Proteins
  • Repressor Proteins
  • oncogene protein E7, Human papillomavirus type 16