NSUN2 is a glucose sensor suppressing cGAS/STING to maintain tumorigenesis and immunotherapy resistance.

Glucose metabolism is known to orchestrate oncogenesis. Whether glucose serves as a signaling molecule directly regulating oncoprotein activity for tumorigenesis remains elusive. Here, we report that glucose is a cofactor binding to methyltransferase NSUN2 at amino acid 1–28 to promote NSUN2 oligomerization and activation. NSUN2 activation maintains global m⁵C RNA methylation, including TREX2 , and stabilizes TREX2 to restrict cytosolic dsDNA accumulation and cGAS/STING activation for promoting tumorigenesis and anti-PD-L1 immunotherapy resistance. An NSUN2 mutant defective in glucose binding or disrupting glucose/NSUN2 interaction abolishes NSUN2 activity and TREX2 induction leading to cGAS/STING activation for oncogenic suppression. Strikingly, genetic deletion of the glucose/NSUN2/TREX2 axis suppresses tumorigenesis and overcomes anti-PD-L1 immunotherapy resistance in those cold tumors through cGAS/STING activation to facilitate apoptosis and CD8⁺ T cell infiltration. Our study identifies NSUN2 as a direct glucose sensor whose activation by glucose drives tumorigenesis and immunotherapy resistance by maintaining TREX2 expression for cGAS/STING inactivation. [Display omitted] • Glucose promotes oligomerization and activation of NSUN2 by its direct binding to NSUN2 • The glucose/NSUN2 axis maintains TREX2 expression to execute its oncogenic activity • The axis represses cGAS/STING activation to maintain oncogenic activity of cancer cells • The axis drives anti-PD-L1 immunotherapy resistance by restricting cGAS/STING signaling Whether glucose is a signaling molecule directly regulating oncoproteins for tumorigenesis remains elusive. Chen et al. identify NSUN2 as a direct glucose sensor driving tumorigenesis and immunotherapy resistance by maintaining TREX2 expression for cGAS/STING inactivation, thus opening a new avenue for studying novel glucose's actions in regulating diverse biological processes. [ABSTRACT FROM AUTHOR]