UPLC-MS/MS based diagnostics for epithelial ovarian cancer using fully sialylated C4-binding protein

Area of Science:

• Biochemistry
• Proteomics
• Clinical Diagnostics

Background:

• Serum levels of fully sialylated C4-binding protein (FS-C4BP) are significantly elevated in epithelial ovarian cancer (EOC) patients.
• FS-C4BP shows potential as a biomarker for differentiating ovarian clear cell carcinoma from endometrioma.

Purpose of the Study:

• To develop a stable, robust, and reliable liquid chromatography-hybrid mass spectrometry (UPLC-MS/MS) method for quantifying FS-C4BP.
• To validate FS-C4BP as a generalizable clinical biomarker for EOC.

Main Methods:

• Analysis of glycopeptides from 20 μL of trypsin-digested serum glycoprotein using UPLC-MS/MS.
• Optimization of UPLC-MS/MS method for FS-C4BP detection, focusing on the A1958 peptide marker.
• Validation using serum samples from 119 EOC patients and 127 healthy women.

Main Results:

• The UPLC-MS/MS method demonstrated improved performance and robustness for A1958 detection.
• An FS-C4BP index, utilizing the ratio of A1958 to A1813, achieved an 85% area under the curve.
• Combining the FS-C4BP index with carbohydrate antigen-125 levels enhanced diagnostic sensitivity and specificity.

Conclusions:

• The developed UPLC-MS/MS method provides a reliable approach for measuring FS-C4BP.
• FS-C4BP, particularly the A1958/A1813 ratio, shows significant potential as a non-invasive biomarker for EOC detection.
• Integration with CA-125 may further improve EOC diagnostic accuracy.