Specificity: Cytokeratin 5,6 is expressed in many non-keratinizing stratified squamous epithelia including: basal epithelia, hair follicles, trachea, tongue mucosa, as well as basal cells in prostate glands and myoepithelial cells in mammary glands. Cytokeratin 5,6 protein is also found in most epithelial and bispasic mesotheliomas, large cell carcinoma and pulmonary squamous cell carcinomas.