Early Detection Research Network


This biomarker is also known as:
  • MUC-16,
  • Ovarian carcinoma antigen CA125,
  • FLJ14303,
  • mucin 16, cell surface associated,
  • CA125 ovarian cancer antigen,
  • Ovarian cancer-related tumor marker CA125,
  • CA-125,
  • CA125,
  • Mucin-16,
  • MUC16,
  • Mucin 16,


MUC16 (CA125) is a highly glycosylated sialomucin that is expressed on epithelial cell surface, especially on ovarian cancer cells. MUC16 is anchored to the epithelium by a transmembrane domain and is released into the extracellular space by enzymatic cleavage. It is thought to provide a protective, lubricating barrier against particles and infectious agents at mucosal surfaces.


There are no datasets associated with this biomarker.

QA State: Accepted
Type: Protein
HGNC Name: MUC16

The following organs have data associated with this biomarker…


Phase: One
QA State: Curated
Organ-specific information for this biomarker is currently being annotated or is under review. You must be logged in or do not have permission to view any additional information. Contact the Informatics Center if you should have access to this biomarker.


Phase: Three
QA State: Accepted


The best known marker for late stage and to a lesser degree early stage ovarian carcinomas - especially of serous and endometrioid histology. Overexpressed in ovarian carcinomas and ovarian low malignant potential (LMP) tumors as compared to the expression in normal ovarian tissue and ovarian adenomas. CA125, an epithelial sialomucin also called MUC16, is a heavily glycosylated protein with relatively high molecular weight and is the only approved marker for monitoring ovarian cancer. Although sialomucins are transmembrane in location, they can be found in serum. Most of the markers in this category have been identified through approaches in which human cancer cells are used as an antigenic stimulus in animals to raise antibodies, which can then efficiently detect the antigen in human serum. CA125 is the best documented and best performing single marker among the epithelial sialomucins. CA125 can be elevated in early pregnancy and with endometriosis, fibroids or infections of the genital tract. These conditions would affect specificity of the test and the possibility of false positive results.

Performance Comment

Of the 28 ovarian cancer biomarkers tested in prediagnostic specimens, from the PLCO, CA125 remains the the single best biomarker for ovarian cancer and has its strongest signal within six months of diagnosis.

Supporting Study Data

The following studies/protocols provide evidence supporting CA125 indications for the Ovary…

No supporting studies or protocols found.

Organ-Specific Protocols

No organ-specific protocols defined.

Organ-Specific Publications

Organ-Specific Resources

No organ-specific resources defined.

Version 5.0.2