- Myoepithelial cells
Myoepithelial cells (sometimes referred to as Myoepithelium) are cells usually found in
glandular epithelium as a thin layer above thebasement membrane but generally beneath the lumenal cells. These may be positive for alpha smooth muscleactin and can contract and expel thesecretions ofexocrine glands . They are found in thesweat gland ,mammary gland ,lacrimal gland , andsalivary gland . Myoepithelial cells in these cases constitute thebasal cell layer of anepithelium that harbors the epithelial progenitor/stem cells . In the case ofwound healing , myoepithelial cells reactivelyproliferate . Presence of myoepithelial cells in a hyperplastic tissue proves thebenign ity of the gland and, when absent, indicatescancer . Only rare cancers likeadenoid cystic carcinoma s containsmyofibroblast s as one of themalignant components.Markers
Myoepithelial cells are true
epithelial cell s positive forkeratin s, not to be confused with myofibroblasts which are truemesenchymal cell s positive forvimentin . These cells are generally positive foralpha smooth muscle actin (αSMA),cytokeratin 5/6 and other highmolecular weight cytokeratins, p63 andcaldesmon .External links
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* - "Axillary Sweat Gland: Myoepithelium"
* - "thick skin"
* "Simple Tubular Coiled"
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