Differential effects of human papillomavirus type 6, 16, and 18 DNAs on immortalization and transformation of human cervical epithelial cells

The human papillomaviruses (HPVs) are associated with specific benign and malignant lesions of the skin and mucosal epithelia. Cloned viral DNAs from HPV types 6b, 16, and 18 associated with different pathological manifestations of genital neoplasia in vivo were introduced into primary human cervical epithelial cells by electroporation. Cells transfected with HPV16 or HPV18 DNA acquired indefinite lifespans, distinct morphological alterations, and anchorage-independent growth (HPV18), and contain integrated transcriptionally active viral genomes. HPV6b or plasmid electroporated cells senesced at low passage. The alterations in growth and differentiation of the cells appear to reflect the progressive oncogenic processes that result in cervical carcinoma in vivo