Identification of papillomaviral DNA sequences in hairless mouse tumours induced by ultraviolet irradiation.

Papillomas, carcinomas in situ and squamous cell carcinomas were induced using ultraviolet irradiation in the hairless mouse strain Mus musculus HRA/Skh. DNA extracted from biopsies was examined using Mastomys natalensis papillomaviral DNA as a hybridization probe at reduced stringency. Sequences homologous to the probe were detected in 16 of 24 papillomas, five of five carcinomas in situ and six of 38 squamous cell carcinomas. A number of tumour DNAs (16/33) also hybridized with mixed DNAs of human papillomavirus types 11, 13, 16 and 18 at reduced stringency. This suggests a role for the hairless mouse as a laboratory model for the study of the involvement of papillomaviruses in malignant transformations.