Glycosylation in Dermatology: Unveiling the Sugar Coating of Skin Disease

ABSTRACT Glycosylation is a common and complex post‐translational modification (PTM) of proteins, involving the attachment of glycans under the regulation of various enzymes such as glycosyltransferases. Glycosylation facilitates the correct folding of peptide chains, modifies protein conformation and activity, enhances protein stability and influences inter‐protein interactions. N‐glycosylation and O‐glycosylation are two prevalent forms, encompassing a wide range of modifications, including sialylation, fucosylation and galactosylation. In skin tumours, abnormal glycosylation promotes tumour cell proliferation, migration, invasion and metastasis, enhances anti‐tumour immunity, and potentially affects immune checkpoint therapy. In inflammatory and autoimmune skin diseases, abnormal glycosylation in T and B lymphocyte subpopulations regulates antigen recognition, signal transduction, inflammatory factor secretion and immunoglobulin function, disrupting immune system homeostasis and impacting biologic therapy efficacy. Glycosylation correlates with the severity and activity of skin diseases, serving as a potential biomarker for diagnosis, condition assessment and prognosis determination. This review provides an overview of the role of protein glycosylation in melanoma, basal cell carcinoma, squamous cell carcinoma, psoriasis, systemic lupus erythematosus, dermatomyositis and skin aging. It analyses the biosynthetic process of glycosylation, elucidates functional changes in glycoproteins and their metabolism, and offers a theoretical basis for developing new targeted therapies.