Cellular control of human papillomavirus oncogene transcription.

Specific types of human papillomaviruses (HPVs) are closely associated with the development of cervical cancer. The transforming ability of these high-risk HPV types depends on the expression of the viral E6 and E7 oncogenes. It is therefore of particular interest to elucidate the molecular mechanisms that result in the activation of E6/E7 expression during HPV-associated tumorigenesis. Recently, much progress has been made in characterizing the proteins involved in the regulation of HPV oncogene transcription. This review describes the functional significance of cellular factors involved in the transcriptional control of the E6/E7 promoter for the two most common HPV types associated with cervical cancer, HPV16 and HPV18. In addition, we discuss regulatory pathways that may contribute to the epithelial cells specificity of E6/E7 transcription. The definition of the factors that regulate HPV oncogene transcription could provide new insights into the molecular mechanisms activating viral oncogene expression during cervical carcinogenesis and forms an experimental basis for investigating the specific biochemical pathways that contribute to HPV-associated malignant cell transformation.