E6 Protein

  • Felix Hoppe-Seyler
  • Martin Scheffner


HPV DNA is found integrated into the host genome in a high percentage of cervical carcinomas. While integration appears to be random with respect to the host genome, there appears to be some specificity with respect to the viral genome in that integration frequently occurs within the El or E2 ORFs (see also chapter 2). As a consequence of this integration the only viral genes that are regularly expressed in cervical cancers are E6 and E7. This observation implies that the E6 and the E7 ORF encode for the major viral oncoproteins. This hypothesis has been corroborated by several lines of evidence. Most importantly, both E6 and E7 have oncogenic properties in various in vitro cell culture systems as well as in transgenic animal models, and inhibition of E6/E7 expression results in growth arrest and reversion of the malignant phenotype of cell lines derived form cervical cancers. To understand why expression of these viral proteins can contribute to, or can induce, immortalization/transformation of infected cells, it is important to identify and characterize both the properties of E6 and E7 involved in immortalization/transformation and the properties that are necessary for the viral life cycle. However, due to the lack of an appropriate cell culture system for HPV propagation, studies so far have mostly been limited to the characterization of the oncogenic properties of E6 and E7.


Cervical Cancer Human Papilloma Virus Human Papilloma Virus Infection Cervical Cancer Cell Line Human Papilloma Virus Type 
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Copyright information

© Springer-Verlag Berlin Heidelberg 1997

Authors and Affiliations

  • Felix Hoppe-Seyler
  • Martin Scheffner

There are no affiliations available

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