CEA Gene Family
The carcinoembryonic antigen (CEA) gene family comprises 33 genes, 22 of which are expressed. All family members share similar structural features encompassing immunoglobulin (Ig) variable and/or constant domains and therefore constitute members of the large immunoglobulin superfamily. These proteins are either secreted or membrane bound. Several CEACAMs function as homophilic or heterophilic intercellular cell adhesion molecules. CEA, CEACAM1, CEACAM6, and CEACAM7 also play a significant role as regulators of tumor cell proliferation and differentiation and their overexpression (CEA and CEACAM6) or their downregulation (CEACAM1 and CEACAM7) contributes to progression of many epithelial cancers and immune dysfunctions.