CA125 (MUC16) is an antigen recognized by the monoclonal antibody (named OC125) obtained by immunizing mice with ovarian serous cystadenocarcinoma cell line OVCA433. The relative molecular mass of CA125 ranges from 200,000 to 1,000,000. It is a macromolecular glycoprotein and a glycoprotein complex similar to mucin.
CA125 is most commonly found in the serum of patients with epithelial ovarian tumors (serous tumors) and is absent in mucinous ovarian tumors. Serum CA125 is elevated in 80% of patients with epithelial ovarian tumors, and serum CA125 is associated with disease progression in 90% of patients. The level of CA125 in 95% of healthy adult women is less than or equal to 40U/ml, and attention should be paid to if it rises to more than 2 times the normal value.
In addition, ovarian epithelial cancer, cervical cancer, uterine cancer, endometrial cancer, pancreatic cancer, lung cancer, gastric cancer, colorectal cancer, breast cancer also have a certain positive rate of CA125.