Does CA125 binding to mesothelin impact the detection of malignant mesothelioma?
The biomarker mesothelin is a useful diagnostic tool in malignant mesothelioma (MM) patients. It has high specificity but a sensitivity of only 50%. As mesothelin binds CA125, and as CA125 is often elevated in MM, we asked whether this binding affected measurable mesothelin levels in a relevant clinical setting. Mesothelin and CA125 concentrations were measured in the serum of 41 patients with MM. An assay was developed to detect mesothelin bound to CA125. Mesothelin was demonstrated to be bound by CA125 in 9 of 41 MM patients. This binding could be broken by the addition of sodium dodecyl sulphate and diethylenetriaminepenta acetic acid (DTPA) to the samples, however this did not lead to any change in the mesothelin level measured. We therefore conclude that binding of mesothelin to CA125 does not alter the measurement of mesothelin for the detection of MM.
National Centre for Asbestos Related Diseases, School of Medicine and Pharmacology, University of Western Australia, Perth, Western Australia 6009, Australia. jenette.creaney@uwa.edu.au
Jenette
J
Creaney
Ian M
IM
Dick
Hanne
H
Dare
Yvonne
Y
Demelker
Anna K
AK
Nowak
Arthur William
AW
Musk
Bruce W S
BW
Robinson
D000368:Aged; D000369:Aged, 80 and over; D014408:Biomarkers, Tumor / Q000097:blood / Q000378:metabolism*; D018394:CA-125 Antigen / Q000097:blood / Q000378:metabolism*; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D058851:GPI-Linked Proteins / Q000097:blood / Q000378:metabolism*; D006801:Humans; D008297:Male; D000090204:Mesothelin; D008654:Mesothelioma / Q000097:blood / Q000175:diagnosis / Q000378:metabolism*; D008875:Middle Aged; D004369:Pentetic Acid / Q000494:pharmacology; D011485:Protein Binding / Q000187:drug effects; D012680:Sensitivity and Specificity; D012967:Sodium Dodecyl Sulfate / Q000494:pharmacology
D014408:Biomarkers, Tumor; D018394:CA-125 Antigen; D058851:GPI-Linked Proteins; D012967:Sodium Dodecyl Sulfate; D004369:Pentetic Acid; D000090204:Mesothelin