Immunoelectron microscopic studies on cytokeratins in human basal cell carcinoma.

Ultrastructural investigations into the location and the expression of the cytokeratins 7, 8, 10 and 19 were undertaken on ultrathin cryosections of 8 basal cell carcinomas (BCC) using a high resolution immunogold labeling method and five different monoclonal antibodies against specific cytokeratins. The results showed that cytokeratin 10 was expressed only in the differentiated keratinocytes. In contrast to the previously reported biochemical and immunohistochemical studies, in this study cytokeratin 19 was expressed not only in the tumor cells of BCC but also in the normal epidermal keratinocytes. The expression of cytokeratin 7 in BCC could not be confirmed but the lack of expression of cytokeratin 8 was confirmed, excluding its potential role as a specific histopathological marker for BCC.