The E6-E7 region of human papillomavirus type 18 is sufficient for transformation of NIH 3T3 and rat-1 cells.

Plasmids containing the E6 and E7 open reading frames of human papillomavirus type 18 expressed from an autologous transcriptional control region were sufficient for transformation of NIH 3T3 and Rat-1 cells. Transformation by these sequences did not always involve morphological alterations even though anchorage-independent growth occurred at a high frequency. In these cells, the efficiency of transformation by the E6 and E7 construct was equivalent to or, in most cases, better than that observed with the entire viral genome. These data indicate that a major human papillomavirus type 18 transforming function is localized in either the E6 or E7 gene products or both.