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CA125

Basics

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

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Description…

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.

Attributes

QA State: Accepted
Type: Protein
Short Name:
HGNC Name: MUC16

Organs

The following organs have data associated with this biomarker…

Ovary

Attributes

Phase: Three
QA State: Accepted

Overview

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…

PLCO Ovarian Phase III Validation Study

Our preliminary data indicate that the performance of CA 125 as a screening test for ovarian cancer can be improved upon by additional biomarkers. With completion of one additional validation step, we will be ready to test the performance of a consensus marker panel in a phase III validation study. Given the original aims of the PLCO trial, we believe that the PLCO represents an ideal longitudinal cohort offering specimens for phase III validation of ovarian cancer biomarkers.

View more about this study
Biomarker Characteristics Summary
Notes Sensitivity Specificity Prevalence NPV PPV Specific Assay Type
The dataset contains the original values and the log transformed values for CA125, CA15.3, CA19.9, CA72.4, KLK6 (aka HK6), HE4, and OV110 (aka B7-H4). Created by Allison Vitonis. Partners used plate-based assay for B7-H4(Diadexus), HE4, and Kallikrein 6 (as described in (Diamandis EP, Scorilas A, Fracchioli S, Van Gramberen M, De Bruijn H, Henrik A, Soosaipillai A, Grass L, Yousef GM, Stenman UH, Massobrio M, Van Der Zee AG, Vergote I, and Katsaros D, Human kallikrein 6 (hK6): a new potential serum biomarker for diagnosis and prognosis of ovarian carcinoma. J Clin Oncol, 2003. 21(6): p. 1035-43)). Platform-based assays (Roche) were used for CA125, CA15.3, CA72.4 and CA19.9. Unless the volume was insufficient assays were run in duplicate and averaged. These seven markers were chosen based on their performance in the phase II (pre-PLCO) data. This data us available in the file entitle "Harvard_markers_11132008.xls" which is linked to this record on the MUC16 Basics Tab. N/A N/A N/A N/A N/A
Cases chosen with diagnosis of ovarian cancer (on average) 9 months prior. Controls were matched to cases by age and timing of specimen collection including general population controls (50%), false positive CA125 (25%), and family history of breast cancer (25%). All cases (n=60). 41.0 95.0 N/A N/A N/A
Cases diagnosed <= 6 months after draw (n=25) 79.0 95.0 N/A N/A N/A
Cases diagnosed > 6 months after draw (n=35) 15.0 95.0 N/A N/A N/A
Decision Rule

PMID:21372037

Additional Study-Specific Protocols
Study-Specific Publications

No study-specific publications defined.

Study-Specific Resources

No study-specific resources defined.

SPORE/EDRN/PRE-PLCO Ovarian Phase II Validation Study

Create a new set of phase II specimens (160 cases with pre-operative bloods representing major histologic types and including 80 early-staged and 80 late-staged cases, 160 controls with benign disease, 480 general population controls, and a small set of serial Samples collected either at least 3 months apart, but not more than 6 months apart OR between 10 months apart and no more than 14 months apart in 40 healthy controls) will be used to evaluate markers identified in preliminary work. The top 5-10 markers, plus an expanded panel of Luminex markers, will comprise a “working consensus panel” for subsequent analysis in PLCO specimens.

View more about this study
Biomarker Characteristics Summary
Notes Sensitivity Specificity Prevalence NPV PPV Specific Assay Type
The dataset contains the original values and the log transformed values for CA125, CA15.3, CA19.9, CA72.4, KLK6 (aka HK6), HE4, and OV110 (aka B7-H4). Created by Allison Vitonis. Partners used plate-based assay for B7-H4(Diadexus), HE4, and Kallikrein 6 (as described in (Diamandis EP, Scorilas A, Fracchioli S, Van Gramberen M, De Bruijn H, Henrik A, Soosaipillai A, Grass L, Yousef GM, Stenman UH, Massobrio M, Van Der Zee AG, Vergote I, and Katsaros D, Human kallikrein 6 (hK6): a new potential serum biomarker for diagnosis and prognosis of ovarian carcinoma. J Clin Oncol, 2003. 21(6): p. 1035-43)). Platform-based assays (Roche) were used for CA125, CA15.3, CA72.4 and CA19.9. Unless the volume was insufficient assays were run in duplicate and averaged. These seven markers were chosen based on their performance in the phase II (pre-PLCO) data. This data us available in the file entitle "Harvard_markers_11132008.xls" which is linked to this record on the MUC16 Basics Tab. N/A N/A N/A N/A N/A
For early stage (more than 12 months prior to diagnosis), using all controls. Results from preliminary analysis, 50% of 114 sample set. Daniel Cramer laboratory. 50.0 95.0 N/A N/A N/A
For late stage (within 12 months of diagnosis), using all controls. Results from preliminary analysis, 50% of 114 sample set. Daniel Cramer laboratory. N/A 95.0 N/A N/A N/A
Cases chosen with diagnosis of ovarian cancer (on average) 9 months prior. Controls were matched to cases by age and timing of specimen collection including general population controls (50%), false positive CA125 (25%), and family history of breast cancer (25%). All cases (n=60). 41.0 95.0 N/A N/A N/A
Cases diagnosed <= 6 months after draw (n=25) 79.0 95.0 N/A N/A N/A
Cases diagnosed > 6 months after draw (n=35) 15.0 95.0 N/A N/A N/A
Decision Rule

PMID:21372037

Additional Study-Specific Protocols
Study-Specific Publications

No study-specific publications defined.

Study-Specific Resources

Organ-Specific Protocols

No organ-specific protocols defined.

Organ-Specific Publications

No organ-specific publications defined.

Organ-Specific Resources

No organ-specific resources defined.

Publications

No associated publications found.

2015 EDRN PI Orientation

The New and Continuing EDRN Principal Investigator Orientation will take place October 15–16, 2015 in Bethesda, Maryland.

Announcement 04/08/2015

Thank you to everyone who made the 29th EDRN Steering Committee Meeting a success. The orientation for new and continuing EDRN PIs will be held October 15-16, 2015 on the NCI campus. More information will be available later this summer.

Announcement