Colony-Forming Assay of Human Salivary Gland Tumors: Applications for Chemosensitivity and Histogenetic Studies

Abstract

Eight malignant and nine benign salivary gland neoplasms were cultured using a soft agar technique. Eleven of these tumors were successfully grown, two were contaminated, and only four demonstrated no growth. Cloning efficiency varied from 0.004% to 0.225%. These efficiencies and the 65% successful growth rate are much higher than those reported for head and neck squamous cell carcinomas. Single cell disaggregation with resultant clonal growth can be accomplished with salivary gland neoplasms. Ultrastructural study of colonies from three mixed tumors did not demonstrate distinct epithelial and mesenchymal populations of cells, the expected finding if mixed tumors were composed of two independent cell lines. Rather, mixed tumors invariably consisted of a monoclonal population of cells with evidence of ambivalent, mesenchymal, and epithelial differentiation. Myoepithelial cells were not present. (Arch Otolaryngol 1983;109:709-714) In 1977, Hamburger and Salmon1 described a soft agar colony-form¬ ing assay to measure in vitro the number of clonogenic cells in a given tumor cell population. Further, they described a method to measure the in vitro effects of cytotoxic agents on tumor colony formation. Their early reports and the reports of other inves¬ tigators generated enthusiasm for this assay as a measure of chemotherapeutic sensitivity.

ALDH1 immunohistochemical expression and its significance in salivary adenoid cystic carcinoma

“…One explanation is that adenoid cystic carcinoma stems from stromal cells under appropriate conditions. A study using a colony-forming assay 18 and electron microscopy found that pleomorphic adenomas were monoclonal neoplasms with multidirectional differentiation. It is possible that the stromal cells in adenoid cystic carcinoma can differentiate into epithelial and myoepithelial cells.…”

Histogenesis of salivary gland neoplasms: a postulate with prognostic implications

“…It has an extremely low proliferative rate, even to the consideration that it is probably amitotic (Walker, 1988). The failure of Johns et al, (1983) to find 'acceptable' myoepithelial cells in their clones of pleomorphic adenomas rests in their definition of the cells. They defined the mature myoepithelial cell (Fig.…”

Localization of salivary amylase and epithelial membrane antigen in salivary gland tumours by means of imunoperoxidase and immunogold-silver techniques

“…Although the histopathological features of salivary gland neoplasms are believed to be derived from myoepithelial cells and transformed epithelial ducts, there is a considerable degree of controversy concerning the degree of epithelial and myoepithelial differentiation in some salivary gland tumours (Dardick et al, 1982;Erlandsonef al, 1984;Hubner etal, 1971;Johns et al, 1983;Shirasuna et al, 1980;Welsh and Meyer, 1968).…”