{"type":"root","children":[{"type":"paragraph","children":[{"type":"text","value":"p63 is a transcription factor belonging to the p53 family of proteins, which are involved in the regulation of cell proliferation, differentiation, and apoptosis. There are 6 isoforms of p63 (TAp63α, TAp63β, TAp63γ, ΔNp63α, ΔNp63β, ΔNp63γ), all share a common central region containing a DNA-binding domain and an oligomerization domain. p63 regulates the activity of a multitude of genes involved in growth and development of the ectoderm-derived structures and stratified epithelial tissues.\np63 is involved in the regulation of stem cell populations and in some contexts functions as a tumor suppressor, but may contribute to tumor development and progression. Various epithelial lesions and tumors including squamous and basal cell carcinomas may demonstrate positive staining for p63. p63 is typically observed in basal and myoepithelial cells of stratified epithelia, such as the skin, oral cavity, mammary gland, prostate, and urogenital tract, and has been observed in subtypes of carcinomas which may be morphologically difficult to classify."}]}]}