a type I transmembrane protein present on epithelia and thymocytes that facilitates adhesion of cells to the extracellular matrix; expressed in squamous cell carcinoma.
ITGB4A gene on chromosome 17q25 that encodes an integrin beta chain protein (integrins are noncovalently associated transmembrane glycoprotein receptors, composed of alpha and beta chains). The beta chain encoded by ITGB4 usually associates with alpha 6, serving as a laminin receptor. It plays a key structural role in the hemidesmosomes, regulates keratinocyte polarity and motility and is a central player in the biology of invasive cancer.
ITGB4 mutations are associated with epidermolysis bullosa with pyloric atresia.