Increased Sialylation of Anti-Thomsen-Friedenreich Antigen (CD176)‎ Antibodies in Patients with Gastric Cancer: A Diagnostic and Prognostic Potential

Abstract EN

Aim.

To study whether alterations in the sialylation of antibodies (Ab) specific to the Thomsen-Friedenreich (TF) glycotope have a diagnostic and prognostic potential in gastric cancer.

Methods.

Serum samples were taken from patients with gastric carcinoma (n=142) and controls (n=61).

The level of TF-specific antibodies and their sialylation was detected using ELISA with synthetic TF-polyacrylamide conjugate as antigen and sialic acid-specific Sambucus nigra agglutinin (SNA).

Results.

The level of TF-specific IgM was significantly decreased in cancer compared with controls (P≤0.001).

Cancer patients showed a higher level of SNA binding to anti-TF IgM and IgA (P≤0.001) irrespective of disease stage, tumor morphology, and gender.

Changes in the SNA/Ab index demonstrated moderate sensitivity (66–71%) and specificity (60–73%) for stomach cancer.

The best diagnostic accuracy (100%) was achieved in 29% patients with high SNA binding and low anti-TF IgM level.

This subset of patients demonstrated the poorest survival.

Conclusion.

Our findings are the first evidence that the increased sialylation of TF-specific Abs combined with a low level of anti-TF IgM is strongly linked to gastric cancer and patients survival, which can be used as a novel biomarker for cancer detection and prognosis.