CEA

Carcinoembryonic antigen (CEA) is an acidic glycoprotein mainly produced by the liver, pancreas, and gastrointestinal tract during the fetal period, participating in cell adhesion, immune regulation, and embryonic development. CEA is extremely rare in normal adults, but can be abnormally expressed in cancer cells. So it can be used in the diagnosis of lung cancer, liver cancer, stomach cancer, colorectal cancer, breast cancer and other tumors. Moreover, some research found that the expression level of CEA is negatively correlated with the overall survival of patients, which may be because CEA can affect the cancer cell cycle by regulating Erk 1/2 pathway and promote tumor growth and metastasis by activating Src pathway. Among them, CEA is highly expressed in cervical adenocarcinoma but lowly expressed in endometrioid adenocarcinoma, which makes it useful for assisting in identification, speculated to be related to the malignancy of tumors and the degree of damage to normal tissues. In addition, CEA has good reference value in distinguishing extramammary Paget's disease (+) from Bowen's disease (-) and malignant melanoma (-).