A myoepithelial cell line established from a human pleomorphic adenoma arising in minor salivary gland

Transformed cells were isolated by using tissue culture techniques from a human pleomorphic adenoma. They revealed ultrastructurally myoepithelial and intercalated ductal cells as the neoplastic cell components that arose in the minor salivary gland of the palate. All transformed clones were demonstrated by electron microscopic examination to be only one type of cells having fine structures similar to myoepithelial cells with typical myofibrils in the cytoplasm. Of five clones isolated, one clone with stable growth was inoculated into nude mice, resulting in a production of myoepithelioma with mucinous substance. In addition, these cloned cells and myoepithelioma cells derived from one clone were found to express viral particles in the intercellular spaces. These findings indicate that a human myoepithelial cell line carrying tumorigenicity is established from the pleomorphic adenoma.