Long Noncoding RNA TINCR-Mediated Regulation of Acetyl-CoA Metabolism Promotes Nasopharyngeal Carcinoma Progression and Chemoresistance.

Frontier evidence suggests that dysregulation of long noncoding RNAs (lncRNA) is ubiquitous in all human tumors, indicating that lncRNAs might have essential roles in tumorigenesis. Therefore, an in-depth study of the roles of lncRNA in nasopharyngeal carcinoma (NPC) carcinogenesis might be helpful to provide novel therapeutic targets. Here we report that lncRNA TINCR was significantly upregulated in NPC and was associated positively with poor survival. Silencing TINCR inhibited NPC progression and cisplatin resistance. Mechanistically, TINCR bound ACLY and protected it from ubiquitin degradation to maintain total cellular acetyl-CoA levels. Accumulation of cellular acetyl-CoA promoted de novo lipid biosynthesis and histone H3K27 acetylation, which ultimately regulated the peptidyl arginine deiminase 1 (PADI1)-MAPK-MMP2/9 pathway. In addition, insulin-like growth factor 2 mRNA-binding protein 3 interacted with TINCR and slowed its decay, which partially accounted for TINCR upregulation in NPC. These findings demonstrate that TINCR acts as a crucial driver of NPC progression and chemoresistance and highlights the newly identified TINCR-ACLY-PADI1-MAPK-MMP2/9 axis as a potential therapeutic target in NPC. SIGNIFICANCE: TINCR-mediated regulation of a PADI1-MAPK-MMP2/9 signaling pathway plays a critical role in NPC progression and chemoresistance, marking TINCR as a viable therapeutic target in this disease. ©2020 American Association for Cancer Research.