N-acetyltransferase 10 promotes glioblastoma radioresistance by suppressing immunogenic ferroptosis through N4-acetylcytidine of SLC7A11 mRNA

Background Radiotherapy is the standard treatment for glioblastoma (GBM), but its efficacy is severely compromised by radioresistance. While aberrant RNA modifications contribute to radioresistance, specific epitranscriptomic vulnerabilities remain underexplored. Methods We integrated quantitative proteomics, N 4 -acetylcytidine RNA immunoprecipitation sequencing (acRIP-seq), and CRISPR dependency screens to identify radioresistance drivers in GBM. Mechanisms were investigated through patient cohorts, the use of a catalytically inactive mutant (NAT10-G641E), RNA stability assays, and polysome profiling. Immunological and clinical translational effects were assessed via orthotopic mouse models and computational drug repurposing. Results We identified N-acetyltransferase 10 (NAT10), the RNA N 4 -acetylcytidine (ac4C) writer, as a core driver of GBM radioresistance and poor patient survival. Mechanistically, NAT10 deposits ac4C onto SLC7A11 mRNA, stabilizing its transcript and enhancing translational efficiency, t hereby fortifying cellular antioxidant defenses and enabling GBM cells to evade radiation-induced ferroptosis. Furthermore, targeting NAT10 induced immunogenic cell death (ICD) and orchestrated a “cold-to-hot” tumor microenvironment transformation, characterized by robust CD8 + T cell infiltration. To circumvent the toxicity of existing NAT10 inhibitors, we repurposed pemetrexed as a safe and effective alternative. Pemetrexed disrupted the NAT10/ac4C/SLC7A11 axis, yielding profound synergistic survival benefits when combined with radiotherapy. Conclusions NAT10 promotes GBM radioresistance via ac4C-mediated stabilization of SLC7A11 and evasion of ferroptosis. Repurposing pemetrexed to inhibit NAT10 presents a promising strategy to sensitize refractory GBM to radiotherapy by simultaneously triggering ferroptosis and enhancing anti-tumor immunity.