Targeting FUT1-mediated EGFR fucosylation and COX-2 reverses gemcitabine resistance by activating immunogenic cell death in hepatocellular carcinoma.

Gemcitabine resistance and its deficiencies in initiating ICD (Immunogenic Cell Death) reveal the need for novel therapeutic strategies. EGFR (Epidermal Growth Factor Receptor) is a heavily glycosylated protein aberrantly expressed in cancer cells and promotes tumorigenesis via an unknown mechanism. Here, we identify aberrant fucosylation mediated by FUT1 as a key driver of malignant development in hepatocellular carcinoma (HCC), through which gemcitabine promotes HCC resistance and tumor recurrence via the FUT1/EGFR/pSTAT3 pathway. A synergistic strategy was explored to dismantle the immunosuppressive tumor microenvironment by activating COX-2 (Cyclooxygenase-2)-mediated ICD initiation of gemcitabine and reversing FUT1-mediated tumor progression induced by gemcitabine treatment. Mechanistically, we demonstrated that PGE2 (Prostaglandin E2), generated by COX2, acts as an iDAMP (Damage-Associated Molecular Pattern) that inhibits gemcitabine- elicited ICD development and suppresses immune activation. And gemcitabine treatment stress enhances the expression of FUT1 to mediate drug resistance. By exploring a novel naphthalimide-GlcNAc conjugate, named FGNA, we developed a synergistic effect to specifically sensitize HCC to gemcitabine by inhibition of FUT1-mediated aberrant N-glycosylation of EGFR and COX2 in a macrophage-dependent manner. Additionally, further research found tumor-associated macrophages were polarized by FGNAvia decreasing COX-2 expression. Taken together, this study highlights the importance of regulating FUT1 expression to alleviate gemcitabine chemotherapy stress and inhibiting COX2 to activate gemcitabine's ICD initiation and enhance antitumor immunity, suggesting that co-targeting FUT1 and COX-2 is a promising therapeutic approach.