Use

p63 is a homologue of the p53 gene and is necessary for normal breast and prostate development. Unlike other markers of myoepithelial cells and basal cells, p63 immunoreactivity is localized to the nucleus of the cells, which can offer distinct advantages over cytoplasmic labeling in certain types of cases. As a marker of myoepithelial and basal cells, p63 is extremely useful in diagnostic surgical pathology, particularly when examining difficult breast biopsies and prostate biopsies. p63 is also a marker of squamous cell and epithelial carcinomas.