Glycoprotein carbohydrates

Glycoprotein carbohydrates, also known as glycans, are complex oligosaccharide chains covalently attached to proteins, playing a fundamental role in defining the structural and functional identity of the proteome (Varki, 2017). These carbohydrates are involved in a vast array of biological processes, including protein folding, stability, and the mediation of cell-cell and cell-matrix interactions through recognition by lectins and other receptors (Moremen et al., 2012). In various diseases, particularly cancer, the glycosylation patterns of proteins are frequently altered, leading to the expression of tumor-associated carbohydrate antigens (TACAs) that facilitate metastasis and allow tumors to evade the immune system (Pinho & Reis, 2015). Therapeutic strategies targeting these glycans include the use of monoclonal antibodies, glycan-mimetic inhibitors that block adhesion molecules like selectins, and drugs that inhibit glycan-processing enzymes such as neuraminidase (Fuster & Esko, 2005). For example, neuraminidase inhibitors prevent viral release by blocking the cleavage of sialic acid from cell surface glycoproteins, while selectin antagonists disrupt leukocyte recruitment in inflammatory conditions (Ohtsubo & Marth, 2006). Given their ubiquity and functional diversity, glycoprotein carbohydrates represent a critical frontier for the development of novel diagnostics and targeted therapies across oncology, immunology, and infectious diseases. However, the structural complexity and heterogeneity of glycans present significant challenges for drug design and standardization.

Other names

GlycansOligosaccharidesPolysaccharidesSugar chainsGlycosyl moietiesN-linked glycansO-linked glycans

Drugs targeting glycoprotein carbohydrates typically function by inhibiting glycan-binding receptors (e.g., selectin antagonists), blocking glycan-processing enzymes (e.g., neuraminidase inhibitors), or directly binding to specific carbohydrate motifs using monoclonal antibodies or lectin-mimetics (Varki, 2017; Pinho & Reis, 2015).