Polyoma virus, as a model for viral skin carcinogenesis.

Polyoma virus is presented as the simplest model of transformation by a DNA virus. The three possible ways of virus/cell interaction are recalled: lytic infection, abortive infection and malignant transformation. Nuclear and surface antigenic modifications are also recalled as well as their possible correlation with the transformation mechanism. Lastly, in "in vivo" systems, we have tried to schematize the interactions of host and virus-induced tumour.