Epithelial cell adhesion molecule

The epithelial cell adhesion molecule (English epithelial cell adhesion molecule, EpCAM ) is a surface protein and cell adhesion molecule, which is found on the cell surface of various epithelial cells and mediates among other cell-cell contacts. EpCAM is a target molecule in cancer antibody treatment of malignancies of epithelial cells.

Properties

EpCAM is found at the basolateral cell surface of high or isoprismatic epithelial cells such as the cells of the gastric mucosa, the bile ducts, the mucosa of the urinary bladder, bronchi, but also in the follicular epithelium of the thyroid gland. In squamous epithelia such as the skin or the mucous membrane of the mouth, it is not to be found.

In rapidly dividing cells, its synthesis is increased. This is done partly physiologically as in embryonic development, but also with usually rapidly multiplying tumor cells. EpCAM on tumor cells may be formed on the cell types and are found on the cell surface, which normally form no EpCAM such as squamous. Thus represents EpCAM is a tumor-associated antigen, for some tumors, which is used for the accurate diagnosis of these tumors as well as for a specific therapy. In tumor cells a reduced gene expression of EpCAM is associated with a higher metastatic rate. For the monoclonal antibody Catumaxomab EpCAM is the target molecule.

Function

EpCAM molecules are transmembrane molecules. The extracellular portion of a molecule goes with the extracellular portion of another molecule RpCAM a bond. Therefore, EpCAM is also called homophilic ( same binding ) cell adhesion molecule. Here, the bond held with molecules of the same cell and a neighboring cell. The intracellular share an EpCAM binds to proteins of the cytoskeleton.

Mutation of the EpCAM responsible for the clinical picture of Intestinal epithelial dysplasia ( tufting enteropathy synonymous ). In this rare disease, it comes a few days after birth to intractable watery diarrhea by the altered intestinal mucosa cells with the need for parenteral nutrition.