The NSUN2-YBX1 axis enhances 5-Methylcytosine modification to facilitate NPM1-mediated nuclear translocation of PKM2, augmenting the Warburg effect and promoting nasopharyngeal carcinoma progression in a mouse model.

BACKGROUND: Nasopharyngeal carcinoma (NPC) is notable not only for its distinct geographic and ethnic distribution but also for its metabolic alterations. A key feature of NPC is its reliance on aerobic glycolysis for energy production. This shift from oxidative phosphorylation to glycolysis provides cancer cells with a metabolic advantage, supporting rapid growth and survival. Targeting aerobic glycolysis has therefore emerged as a promising therapeutic strategy. METHODS: RT-qPCR, Western blot, IHC, and IF staining were used to examine gene and protein expression levels. Cell viability, proliferation, migration, and invasion were measured using the CCK-8 assay, colony formation assay, and transwell assay, respectively. Interactions among NPM1, PKM2, NSUN2, and YBX1 were examined using RIP, Co-IP, MeRIP, RNA pulldown, and dual-luciferase reporter assays. Aerobic glycolysis and oxidative phosphorylation (OXPHOS) levels were analyzed using the XF96 metabolic analyzer. Additionally, an in vivo mouse model of NPC was established for further validation. RESULTS: NPM1 was abnormally elevated in NPC tissues and cells. Silencing of NPM1 inhibited aerobic glycolysis, suppressed NPC progression and metastasis, and reduced PKM2 nuclear translocation. Mechanistically, NPM1 physically interacted with PKM2 to promote its nuclear localization, while the NSUN2/YBX1 axis upregulated NPM1 expression through m5C modification, stabilizing NPM1 mRNA. CONCLUSION: The NSUN2-YBX1 axis induces m5C modification of NPM1, leading to increased NPM1 stability and its expression. This upregulation facilitates the nuclear translocation of PKM2, which promotes aerobic glycolysis and drives the proliferation and metastasis of NPC. These findings highlight the potential of targeting NPM1 as a novel therapeutic approach for NPC.