Complete disruption of Notch signaling during development of the squamous epithelium of transgenic mice by either tissue specific Notch deletion [90, 91], epithelial deletion of the RPB/j -binding subunit of the Notch transcription complex [92, 93], or expression of a dominant negative MAML1 [94] all result in loss of squamous differentiation and squamous cell carcinomas. This evidence concerns the gene MAML1 and squamous cell carcinoma.