Background：CD326 is also known as Ep-CAM, tumor associated calcium signal transducer 1, epithelial cell surface antigen, epithelial glycoprotein 2, EGP2, adenocarcinoma associated antigen, and TROP1. CD326 is a type I transmembrane protein containing six disulfide bridges and one THYRO domain. This cell surface glycosylated 40 kD protein is highly expressed in bone marrow, colon, lung, and most normal epithelial cells and is expressed on carcinomas of gastrointestinal origin. Recently, it has been reported that CD326 expression occurs during the early steps of erythrogenesis. CD326 functions as a homotypic calcium-independent cell adhesion molecule and is believed to be involved in carcinogenesis by its ability to induce genes involved in cellular metabolism and proliferation. CD326 antigen is an immunotherapeutic target for the treatment of human carcinomas.
