TENASCIN - A MODULATOR OF DEVELOPMENT AND TUMORIGENESIS IN HUMAN SALIVARY-GLANDS

Tenascin (TN) is an extracellular matrix (ECM)protein which is associa ted with embryonal and fetal development, It is expressed at epithelia l-mesenchymal interfaces in normal growth, proliferative disorders, an d neoplasms. Human salivary gland tumors contain mucous material of ep ithelial origin and ECM proteins, including TN, originating from non-e pithelial tumor cells. In fact, many cells in salivary gland tumors, i n particular in pleomorphic adenoma (mixed tumors), produce ECM protei ns, These are modified or neoplastic myoepithelial cells and non-lumin al cell which synthesize fibronectin, TN and other ECM proteins, Cells presenting chondroid changes are derived from these ECM protein-produ cing cells, The present review addresses TN expression in these cells.