Abstract: Objective To evaluate the relationship between desmosome-related proteins and epidermal tumors. Methods Using anti-desmoglein 1 and 2 monoclonal antibodies, expression of desmoglein 1 and 2 was examined by an immunohistochemical staining method in various epidermal tumors such as squamous cell carcinoma (SCC), actinic keratosis(AK), keratoacanthoma(KA) and seborrhoeic keratosis(SK). Results Desmoglein 1 and 2 were strongly expressed in intercellular space of whole epidermis in normal human skin. Expression of desmoglein 1 and 2 was markedly reduced or absentin SCC cells. Compared with normal epidermal cells, expressi on of desmoglein 1 and 2 was equal to or reduced,with complete absence of staining in dysplastic areas in AK cells. Extensive pericellur staining of desmoglein 1 and 2 was found in KA and SK cells, similar to that observed in normal epidermis. Conclusion Expression of desmoglein 1 and 2 is markedly reduced or absent i n human malignant epidermal cancers, reduction of these molecules may contribute to invasiveness and metastasis of epidermal carcinomas.

Key words: Carcinoma, squamous cell, Keratosis, Keratoacanthoma, Keratosis, seborrhoeic, Desmoglein