Mannose antibody levels in gastric cancer patients (literature review and clinical and experimental study)

Introduction. Glycans play an important role in the pathogenesis of malignant neoplasms, including stomach cancer. In recent years, the attention of many researchers has been drawn to mannose (Man) – hexose, which is an indispensable component of all N-chains of glycoproteins involved in both normal physiological and pathological processes.

Aim. To investigate the role of innate immunity factors and ways to influence them through mannose and mannose-containing glycans in gastric cancer patients.

Materials and methods. Data on the role of mannose – one of the key monosaccharides in the formation of glycoprotein N-chains – and its binding receptors (mannose receptor, mannose-binding lectin, antibodies) in gastric cancer since 2006 are presented. Levels of anti-glycan antibodies in blood serum samples of 235 gastric cancer patients and 76 healthy donors were evaluated using a glycochip.

Results. It has been shown that the level of IgM-class antibodies to Manβ – the core part of N-glycans – in gastric cancer patients is significantly lower compared to the donor group, regardless of age (p = 0.0001). To assess the effect of age on the levels of antiglycan antibodies, patients were divided into two subgroups – before and after 45 years. In the group under 45 years of age, significant differences in the levels of antiglycan antibodies to Manβ persisted, while significant differences in the levels of antiglycan antibodies to Manβ1-4GlcNAcβ were not observed. when comparing groups of patients and donors older than 45 years, the levels of antibodies to Manβ and Manβ1-4GlcNAcβ were significantly higher only in donors.

Conclusion. Deficiency of humoral immunity may be one of the key factors in the initiation and progression of carcinogenesis in humans. In our work, in patients with stomach cancer, we revealed a deficiency of antiglycan antibodies to Manβ and to Manβ1-4GlcNAcβ – core fragments of N-chains of glycoproteins, and the deficiency increased with age. The results of the study are a promising platform for further research aimed not only at studying the role of anti-mannose antibodies, but also at developing approaches to adoptive immunoprophylaxis.