Changes in serum IgG oligosaccharide chains with prostate cancer progression

Area of Science:

• Biochemistry
• Glycobiology
• Oncology

Background:

• Altered serum IgG oligosaccharide structures are observed in B cell tumors and autoimmune diseases.
• Current serum tumor markers include cancer-associated carbohydrate epitopes CA72-4 and CA15-3.
• Prostate cancer (PCa) diagnosis and monitoring rely on serum prostate-specific antigen (PSA) levels.

Purpose of the Study:

• To analyze serum IgG oligosaccharide chain structure in PCa patients using fluorophore-associated carbohydrate electrophoresis (FACE).
• To evaluate the relationship between IgG oligosaccharide structure changes and serum PSA concentration in PCa.
• To explore the potential of IgG glycosylation analysis as an auxiliary marker for PCa progression.

Main Methods:

• Serum IgG oligosaccharide chains from 12 PCa patients and 10 healthy controls were analyzed by FACE.
• Serum PSA levels were quantified using enzyme immunoassay.
• Specific oligosaccharide fractions (Fr 1, Fr 2, Fr 4) were quantified and ratios calculated.

Main Results:

• Fr 1 and Fr 2 (monogalactosyl and digalactosyl oligosaccharides) significantly decreased with PCa progression (p<0.05).
• Fr 4 (agalactosyl IgG oligosaccharide) significantly increased with PCa progression (p<0.05).
• A significant correlation (r=0.84, p<0.05) was found between serum PSA levels and the Fr 4/Fr 1+2 ratio in PCa patients.

Conclusions:

• Changes in serum IgG oligosaccharide structure during PCa progression are linked to aberrant glycosylation in metastatic disease.
• FACE analysis of serum IgG oligosaccharide structure shows potential as an auxiliary indicator for monitoring PCa progression alongside PSA.