Immunolocalization of desmoglein and intermediate filaments in human oral squamous cell carcinomas

Background. Information is limited as to how to predict the malignant behavior of the oral squamous cell carcinomas. The invasive and metastatic phenotype of the carcinoma cells may be related to changes in the expression of desmosomal and cytoskeletal proteins. Methods. To investigate the expression of desmoglein, cytokeratins, and vimentin, 22 biopsy specimens of oral squamous cell carcinomas were examined by immunohistochemistry. The data were analyzed by morphometry with reference to the cell differentiation, mode of invasion, and cervical lymph node metastasis. Results. The expression of desmoglein, a major desmosomal glycoprotein, was remarkably reduced in the poorly differentiated, highly invasive, and metastatic carcinomas. Although the immunohistochemical expression of cytokeratins in the carcinoma cells was a good marker for the differentiation status of the carcinomas, the level of expression demonstrated no correlation with tumor invasiveness or lymph node metastasis. On the other hand, the vimentin expression was inversely correlated to the differentiation and mode of invasion, and carcinomas in the metastatic group had significantly higher levels of vimentin expression than the nonmetastatic group. Conclusion. The results suggest that immunohistochemical examination of desmoglein and vimentin in oral squamous cell carcinomas is valuable in evaluating the malignant behavior of tumors.