Perinuclear and cytoplasmic distribution of desmoglein in esophageal squamous cell carcinomas

The desmosomal glycoproteins desmoglein (Dsg) and desmocollin (Dsc) are mem bers of the cadherin family of cell adhesion molecules. They play an import ant role in epithelial adhesion. To observe the distribution pattern of Dsg in esophageal squamous cell carcinomas (SCC), immunohistochemical and immu noelectron microscopic analyses were performed. Immunohistochemically, norm al esophageal squamous cells strongly expressed Dsg at the cell-cell bounda ries, while moderately differentiated esophageal SCC cells showed a perinuc lear distribution in addition to the cell boundary staining. At the ultrast ructural level, the reaction product was concentrated at the desmosomes in the cell membrane region of normal epithelial cells, but was reduced at the membrane and found throughout the cytoplasm as well as in the surrounding outer nuclear envelope in SCC cells. These results demonstrate an aberrant distribution of Dsg in SCC cells. This may have important consequences for invasion and metastasis, as it may indicate loosened intercellular adhesion .