Expression of a carbohydrate differentiation antigen, stage-specific embryonic antigen 1, in human colonic adenocarcinoma.

The expression of the carbohydrate structure defined by monoclonal antibody to murine stage-specific embryonic antigen 1 (SSEA-1) was examined, using immunofluorescence, in formalin-fixed, paraffin-embedded sections of normal fetal and adult human colon and human colonic adenocarcinoma. SSEA-1 was expressed in all human colonic adenocarcinoma tissues examined, although in some cases the staining was heterogeneous. In normal human colonic mucosa, under the conditions used, faint staining was seen in the lower crypts and in only 26% of the crypts examined. When human fetal colon was tested, SSEA-1 was expressed in much larger amounts and in over 50% of all crypts. Transitional mucosa, immediately adjacent to human colonic adenocarcinomas, was also tested, and in this case, increased SSEA-1 expression was seen not only in the lower crypts but also in the upper crypts and surface epithelium. These results show that the increased expression of SSEA-1 in human colonic adenocarcinoma is an oncodevelopmental marker for this cancer. In addition, the results suggest that increased expression of SSEA-1 may be a preneoplastic change in human colon.