Long Noncoding RNA NEAT1, Regulated by the EGFR Pathway, Contributes to Glioblastoma Progression Through the WNT/β-Catenin Pathway by Scaffolding EZH2

Purpose: Long noncoding RNAs have been implicated in gliomagenesis, but theirmechanisms of action are mainly undocumented. Through public glioma mRNA expression data sets, we found that NEAT1 was a potential oncogene. We systematically analyzed the clinical significance and mechanism of NEAT1 in glioblastoma. Experimental Design: Initially, we evaluated whether NEAT1 expression levels could be regulated by EGFR pathway activity. We subsequently evaluated the effect of NEAT1 on the WNT/beta-catenin pathway and its target binding gene. The animal model supported the experimental findings. Results: We found that NEAT1 levels were regulated by EGFR pathway activity, which was mediated by STAT3 and NF kappa B (p65) downstream of the EGFR pathway. Moreover, we found that NEAT1 was critical for glioma cell growth and invasion by increasing beta-catenin nuclear transport and down-regulating ICAT, GSK3B, and Axin2. Taken together, we found that NEAT1 could bind to EZH2 and mediate the trimethylation of H3K27 in their promoters. NEAT1 depletion also inhibited GBM cell growth and invasion in the intracranial animal model. Conclusions: The EGFR/NEAT1/EZH2/beta-catenin axis serves as a critical effector of tumorigenesis and progression, suggesting new therapeutic directions in glioblastoma. (C) 2017 AACR.