BACKGROUND: Mucoepidermoid carcinomas (MECs) are the most common malignant tumor of the salivary glands; however, the histogenesis of MECs has been still controversial. This study was undertaken to investigate the histogenesis of MECs by the examination of their collagen gel-based coculture tissue and transplanted tumors. METHODS: Two cell lines from a primary and a metastatic MECs were established and characterized by the mutational analysis of the p53 gene and in vivo tumorigenicity in athymic nude mice. Collagen gel-based organotypic cocultures were performed, and the ultrastructural and immuncohistochemical findings were examined. RESULTS: Two cell lines demonstrated p53 point mutation at the same codon. A metastatic cell line of MEC showed in vivo tumorigenicity. Transplanted tumors and the collagen gel-based culture tissues showed poorly differentiated squamous cell carcinomas devoid of mucous cell differentiation; however, they disclosed the differentiation of myoepithelial cells. CONCLUSIONS: MECs appear to be centered on the squamous cell differentiation, and the specific differentiation of myoepithelial or mucous cells seems to be modulated by the property of microenvironment.
All Science Journal Classification (ASJC) codes
- Pathology and Forensic Medicine
- Oral Surgery
- Cancer Research