FUT8 (fucosyltransferase 8) is the sole enzyme responsible for catalyzing the addition of α1,6-fucose to the innermost GlcNAc residue of N-linked glycans, a modification known as core fucosylation 1. This glycosylation process is essential for protein stability and function across multiple physiological contexts. FUT8-mediated core fucosylation regulates critical cellular processes including immune responses, where it modulates checkpoint proteins like B7H3 and PD-L2, contributing to immune evasion in cancers 23. The enzyme also controls EGFR signaling through core fucosylation, affecting downstream pathways including JAK1-STAT3 activation 4. In reproductive biology, FUT8 is indispensable for follicular development by regulating FSH receptor function and granulosa cell-oocyte interactions 5. FUT8 is frequently upregulated in various cancers and plays roles in tumor progression, metastasis, and therapeutic resistance 1. Clinically, FUT8 deficiency causes congenital disorder of glycosylation with defective fucosylation, while its overexpression is associated with poor prognosis in multiple cancer types. Therapeutic targeting of FUT8 shows promise in combination therapies, particularly in enhancing anti-tumor immune responses and improving treatment efficacy.