Expression of desmosomal and extracellular matrix proteins in human and experimental oral squamous cell carcinomas visualized by desmoglein-1 and 2 and stromelysin-3

ABSTRACT

Desmosomal and extracellular matrix [ECM] proteins in human oral squamous cell carcinoma from different sites were compared with those of DMBA-induced hamster cheek pouch carcinoma. Immunohistochemical staining utilizing monoclonal antibodies against desmoglein-l and 2 [Dsg-l and 2] and stromelysin-3 [ST-3] as markers for desmosomal and ECM alterations, respectively, on paraffin sections was performed. The results showed that the expression of Dsg-l and 2 was found to be correlated with the state of differentiation of carcinoma cells in both human oral squamous cell carcinoma and hamster cheek pouch carcinoma. The expression of Dsg-l and 2 was remarkably reduced in the poorly differentiated squamous cell carcinoma type compared to the well differentiated form. The expression pattern of ST-3 was, in contrast to Dsg-l and 2, shown to be correlated with tumor invasiveness rather than the differentiation state. Qverexpression of ST-3 was seen in stromal fibroblasts surrounding invasive nests and, also, in cancer cells themselves in both human and hamster cheek pouch squamous cell carcinomas with wide distribution in hamster carcinoma compared to human oral carcinoma. Interestingly, in carcinoma cells, overexpression of ST-3 was constantly associated with infiltrating edges of the tumor cells. This finding suggests that ST-3 expression depends on the interactions of epithelial and stromal cells. The results suggest that Dsg-1 and 2 and ST-3 are useful as tumor markers in human oral squamous cell carcinoma as well as in DMBA-induced cheek pouch squamous cell carcinoma. DMBA-induced hamster cheek pouch squamous cell carcinoma is a reliable model, immunohistochemically, for human oral squamous cell carcinoma