Ptc1 heterozygous knockout mice as a model of multi-organ tumorigenesis.

Mutations in the Ptc1 gene are responsible for basal cell nevus (BCN) syndrome, and are commonly found in sporadic basal cell carcinomas (BCC) and in medulloblastoma (MB). Ptc1 hemizygosity in mice underlies this model's susceptibility to multi-organ tumorigenesis. Similar to BCN syndrome patients, the Ptc1 mouse model is characterized by tumor predisposition and radiation hypersensitivity. Ptc1(+/-) mice develop spontaneous rhabdomyosarcoma (RMS) and medulloblastoma (MB), as well as BCC following radiation exposure. The close phenotypic resemblance to the human disease makes these mice a unique preclinical model to test chemopreventive and therapeutic interventions.