CEA
Carcinoembryonic antigen (CEA) describes a set of highly related glycoproteins involved in cell adhesion. CEA is normally produced in gastrointestinal tissue during fetal development, but the production stops before birth. Therefore, CEA is usually present only at very low levels in the blood of healthy adults. However, the serum levels are raised in some types of cancer, which means that it can be used as a tumor marker in clinical tests.
CEA are glycosyl phosphatidyl inositol (GPI) cell surface anchored glycoproteins whose specialized sialofucosylated glycoforms serve as functional colon carcinoma L-selectin and E-selectin ligands, which may be critical to the metastatic dissemination of colon carcinoma cells. Immunologically they are characterized as members of the CD66 cluster of differentiation.
References
- Boehm, M. K.; Perkins, S. J. (2000). “Structural models for carcinoembryonic antigen and its complex with the single-chain Fv antibody molecule MFE23”. FEBS Letters 475 (1): 11–16. doi:10.1016/S0014-5793(00)01612-4. PMID 10854848.
- Thomas SN, Zhu F, Schnaar RL, Alves CS, Konstantopoulos K (Jun 2008). “Carcinoembryonic antigen and CD44 variant isoforms cooperate to mediate colon carcinoma cell adhesion to E- and L-selectin in shear flow”. J Biol Chem 283 (23): 15647–55. doi:10.1074/jbc.M800543200. PMC 2414264. PMID 18375392.