Abstract
BACKGROUND: Protein glycosylation is the enzymatic addition of sugar chains to specific protein sites and part of this process has a crucial functional modification associated with carcinogenesis and cancer progression. This study aimed to profile and confirm aberrant immunoglobulin G (IgG) protein glycosylation in sera obtained from individuals with breast cancer (BC), with emphasis on breadth of lectin panel and subtype-specific patterns. METHODS: A total of 185 sera underwent lectin microarray analysis with 56 lectins. Validation was performed on sera from an additional 20 BC patients and 6 healthy controls. RESULTS: Differential binding intensities of IgG glycans to Agaricus bisporus lectins (ABA) and Salvia sclarea (SSA) were observed between BC patients and healthy controls (P<0.05). In hormone receptor-positive (HR(+)) vs. HR(-) BC, lectins Hippeastrum hybrid lectin (HHL), Morniga M (MNA-M), datura stramonium lectin (DSL), and iris hybrid lectin (IRA) showed significantly lower glycan levels (P<0.05). human epidermal growth factor receptor-2-positive (HER2(+)) vs. HER2-negative (HER2(-)) BC exhibited significantly higher glycan levels for lectins Jacalin, Artocarpus integrifolia (AIA), MNA-M, HHL, narcissus pseudonarcissus lectin (NPL), Galanthus nivalis lectin (GNL), and soybean agglutinin (SBA) (P<0.05). Verification confirmed increased ABA and SSA in BC sera (P<0.05). SSA, HHL, and NPL recognized glycans in serum IgG from BC subtypes, as confirmed by lectin microarray (P<0.05). This study utilized lectin microarray analysis to profile changes in serum IgG glycosylation patterns in BC. CONCLUSIONS: By employing a broad 56-lectin microarray and subtype analysis, our results reveal distinct serum IgG glycosylation profiles associated with different BC molecular markers. These findings offer a novel framework for investigating disease pathogenesis and identifying candidate biomarkers for BC.