Dataset Information

The tumor microenvironment strongly impacts master transcriptional regulators and gene expression class of glioblastoma.

ABSTRACT: The Cancer Genome Atlas (TCGA) project has generated gene expression data that divides glioblastoma (GBM) into four transcriptional classes: proneural, neural, classical, and mesenchymal. Because transcriptional class is only partially explained by underlying genomic alterations, we hypothesize that the tumor microenvironment may also have an impact. In this study, we focused on necrosis and angiogenesis because their presence is both prognostically and biologically significant. These features were quantified in digitized histological images of TCGA GBM frozen section slides that were immediately adjacent to samples used for molecular analysis. Correlating these features with transcriptional data, we found that the mesenchymal transcriptional class was significantly enriched with GBM samples that contained a high degree of necrosis. Furthermore, among 2422 genes that correlated with the degree of necrosis in GBMs, transcription factors known to drive the mesenchymal expression class were most closely related, including C/EBP-?, C/EBP-?, STAT3, FOSL2, bHLHE40, and RUNX1. Non-mesenchymal GBMs in the TCGA data set were found to become more transcriptionally similar to the mesenchymal class with increasing levels of necrosis. In addition, high expression levels of the master mesenchymal factors C/EBP-?, C/EBP-?, and STAT3 were associated with a poor prognosis. Strong, specific expression of C/EBP-? and C/EBP-? by hypoxic, perinecrotic cells in GBM likely account for their tight association with necrosis and may be related to their poor prognosis.

SUBMITTER: Cooper LA

PROVIDER: S-EPMC3354586 | biostudies-literature | 2012 May

REPOSITORIES: biostudies-literature

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The tumor microenvironment strongly impacts master transcriptional regulators and gene expression class of glioblastoma.

Cooper Lee A D LA Gutman David A DA Chisolm Candace C Appin Christina C Kong Jun J Rong Yuan Y Kurc Tahsin T Van Meir Erwin G EG Saltz Joel H JH Moreno Carlos S CS Brat Daniel J DJ

The American journal of pathology 20120320 5

The Cancer Genome Atlas (TCGA) project has generated gene expression data that divides glioblastoma (GBM) into four transcriptional classes: proneural, neural, classical, and mesenchymal. Because transcriptional class is only partially explained by underlying genomic alterations, we hypothesize that the tumor microenvironment may also have an impact. In this study, we focused on necrosis and angiogenesis because their presence is both prognostically and biologically significant. These features w ...[more]

PMID: 22440258

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Dataset Information

The tumor microenvironment strongly impacts master transcriptional regulators and gene expression class of glioblastoma.

Publications

The tumor microenvironment strongly impacts master transcriptional regulators and gene expression class of glioblastoma.

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