CA-125 Cancer Antigen-125 Discovered in l981 The 125th antibody produced against the ovarian cancer cell line that was being studied

CA-125 (cancer antigen 125 or carbohydrate antigen 125) also known as mucin 16 or MUC16 encoded by the MUC16 gene MUC16 is a member of the mucin family glycoproteins a tumor marker or biomarker that may be elevated in the blood of some patients with specific types of cancers or other benign conditions

22,000 amino acids largest membrane associated mucin

Function creates a hydrophilic environment that acts as a lubricating barrier against foreign particles and infectious agents on the apical membrane of epithelial cells the cytoplasmic tail of MUC16 has been shown to interact with cytoskeleton

Biomarker most frequently used biomarker for ovarian cancer detection CA-125 has limited specificity for ovarian cancer may also be elevated in other cancers, including endometrial cancer, fallopian tube cancer, lung cancer, breast cancer and gastrointestinal cancer may also be elevated in a number of relatively benign conditions, such as endometriosis several diseases of the ovary, menstruation and pregnancy.

suppressing the response of natural killer cells can protect tumor cells from the immune system

Tests First test was radioimmunoassay Commercial ELISA is now available Monitoring levels in postmenopausal women appears significant to diagnose ovarian cancer early.