UBR5 metabolically reprograms nasopharyngeal carcinoma cells to promote glycolysis and M2 polarization via SPLUNC1 signaling

Nasopharyngeal carcinoma (NPC) is the most common cancer originating in nasopharynx. Metabolic reprogramming plays a critical role in tumor progression. Exploring mechanisms underlying metabolic reprogramming contributes to deeper understanding of NPC pathogenesis. Here, we found downregulation of RORA and SPLUNC1 in NPC, and RORA downregulation indicates poor prognosis. RORA binds to SPLUNC1 promoter to induce its transcription, and RORA overexpression inhibits cell proliferation and glycolysis by directly upregulating SPLUNC1. UBR5 inhibits RORA via promoting RORA ubiquitination and degradation, and UBR5 silencing represses proliferation and glycolysis in NPC. Additionally, METTL14, which is highly expressed in NPC, facilitates UBR5 mRNA stability by promoting its m6A modification through IGF2BP2. UBR5/RORA/SPLUNC1 axis facilitates M2 polarization by activating the GPR132 signaling. UBR5 silencing inhibits tumor growth, glycolysis and M2 polarization through RORA/SPLUNC1 signaling in mice. In conclusion, UBR5 promotes proliferation, glycolysis and M2 polarization by metabolically reprograming NPC cells through suppression of the RORA/SPLUNC1 signaling.