[Skin cancer and virus].

Human papillomaviruses (HPV) generally associated with benign skin and anogenital warts. Because several of skin cancers were found to contain HPV-DNA, it has been speculated that certain types of HPV could be specifically associated with cancers. Although HPV-DNAs are not isolated from most of skin cancers, they are often isolated from penile cancers, vulval cancers and anogenital Bowen's diseases. Patients with epidermodysplasia verruciformis start to suffer from disseminated incurable warts during their childhood, and some of these benign lesions often convert to skin cancer in adulthood. Although the disease is very rare, HPV may also play a role in malignant transformation in epidermodysplasia verruciformis. More than 60 types of HPVs distinguished by molecular hybridization techniques. The type of HPV determines the clinical picture of wart and natural fate of HPV-associated lesion. There are two groups of HPVs, which are benign types and malignant types. Viral DNA of malignant type of HPV transforms human keratinocytes in vitro, and the transforming activity has been mapped to the E6 and E7 genes.