The biology of the 17-1A antigen (Ep-CAM).

Department of Pathology, Leiden University Medical Center, The Netherlands.
Journal of Molecular Medicine (Impact Factor: 4.77). 11/1999; 77(10):699-712. DOI: 10.1007/s001099900038
Source: PubMed

ABSTRACT The glycoprotein recognized by the monoclonal antibody (mAb) 17-1A is present on most carcinomas, which makes it an attractive target for immunotherapy. Indeed, adjuvant treatment with mAb 17-1A did successfully reduce the 5 years mortality among colorectal cancer patients with minimal residual disease. Currently the antibody is approved for clinical use in Germany, and is on its way to approval in a number of other countries. New immunotherapeutic strategies targeting the 17-1A antigen are in development or even in early-phase clinical trials. Therefore, a better understanding of the biology of the 17-1A antigen may result in improved strategies for the treatment and diagnosis of human carcinomas. In this review the properties of the 17-1A antigen are discussed concerning tumor biology and the function of the molecule. This 40-kDa glycoprotein functions as an Epithelial Cell Adhesion Molecule, therefore the name Ep-CAM was suggested. Ep-CAM mediates Ca2+-independent homotypic cell-cell adhesions. Formation of Ep-CAM-mediated adhesions has a negative regulatory effect on adhesions mediated by classic cadherins, which may have strong effects on the differentiation and growth of epithelial cells. Indeed, in vivo expression of Ep-CAM is related to increased epithelial proliferation and negatively correlates with cell differentiation. A regulatory function of Ep-CAM in the morphogenesis of epithelial tissue has been demonstrated for a number of tissues, in particular pancreas and mammary gland. The function of Ep-CAM should be taken into consideration when developing new therapeutic approaches targeting this molecule.

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