Activation of estrogen receptor beta signaling reduces stemness of glioma stem cells

We examined the transcriptional changes altered by ERß agonist LY500307 treatment in glioma stem cells (GSCs) by performing global transcriptome analysis. Patient-derived GBM cells (GSC-111010) were subjected to CD133 sorting, and isolated GSCs were treated with either vehicle or LY500307 (5 µM) for 24 h. The RNA was isolated and utilized for RNA-seq analysis. Our results demonstrated that the top pathway altered by LY500307 was the glutamate receptor pathway. Other pathways altered by LY500307 treatment include unfolded protein response, CREB signaling, death receptor signaling, PCP pathway, p53 signaling, and NRF2-mediated oxidative stress response which are known to be involved in stemness and apoptosis. Further, Gene Ontology (GO) analysis revealed that differentially expressed genes were enriched in biological processes, such as regulation of programmed cell death, glutamate receptor signaling pathway, cell communication, and response to unfolded protein. In terms of molecular function, the differentially expressed genes were mainly enriched in glutamate receptor activity, glutamate-gated and transmitter-gated ion channel activity. Overall design: GSC11 cells were treated with either vehicle or LY500307 (5 µM) for 24 h. Total RNA was isolated using RNeasy mini kit according to the manufacturer's instructions (Qiagen, Valencia, CA). Illumina TruSeq RNA Sample Preparation was performed following the manufacturer's protocol. Samples were run on an Illumina HiSeq 2000 in duplicate. The combined raw reads were aligned to UCSC hg19, and genes were annotated by Tophat. Genes were annotated and quantified by the HTSeq-DESeq pipeline.