Cell plasticity in epithelial homeostasis and tumorigenesis.

The adult organism is characterized by remarkable plasticity, which enables efficient regeneration and restoration of homeostasis after damage. When aberrantly activated, this plasticity contributes to tumour initiation and progression. Here we review recent advances in this field with a focus on cell fate changes and the epithelial-mesenchymal transition-two distinct, yet closely related, forms of plasticity with fundamental roles in homeostasis and cancer.