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GSE26616
Mus musculus
6 Downloadable Samples
Affymetrix Mouse Genome 430 2.0 Array (mouse4302)
Description
Polycomb protein group (PcG)-dependent trimethylation on H3-K27(H3K27me3) regulates identity of embryonic stem cells (SCs). How H3K27me3 governs adult SCs and tissue development is unclear. Here, we conditionally target H3-K27-methyltransferases Ezh2 and Ezh1 to address their roles in mouse skin homeostasis. Postnatal phenotypes appear only in doubly-targeted skin, where H3K27me3 is abolished, revealing functional redundancy in EZH1/2 proteins. Surprisingly, while Ezh1/2-null hair follicles (HFs) arrest morphogenesis and degenerate due to defective proliferation and increased apoptosis, epidermis hyperproliferates and survives engraftment. mRNA-microarray studies reveal that despite these striking phenotypic differences, similar genes are upregulated in HF and epidermal Ezh1/2-null progenitors. Featured prominently are a) PcG-controlled non-skin lineage genes, whose expression is still significantly lower than in native tissues, and b) the PcG-regulated Ink4a/Inkb/Arf locus. Interestingly, even though Ink4a/Arf/Ink4b genes are fully activated in HF cells, they only partially so in epidermal-progenitors. Importantly, transduction of Ink4b/Ink4a/Arf shRNAs restores proliferation/survival of Ezh1/2-null HF progenitors in vitro, pointing towards the relevance of this locus to the observed HF phenotypes. Our findings reveal new insights into Polycomb-dependent tissue control and provide a new twist to how different progenitors within one tissue respond to loss of H3K27me3.
Publication Title
EZH1 and EZH2 cogovern histone H3K27 trimethylation and are essential for hair follicle homeostasis and wound repair.
Sample Metadata Fields
Sex, Age, Specimen part
View Samples- Mus musculus
- 4 Downloadable Samples
- Affymetrix Mouse Genome 430 2.0 Array (mouse4302)
Description
Although in vitro studies of embryonic stem cells have identified Polycomb repressor complexes (PRCs) as key regulators of differentiation, it remains unclear as to how PRC-mediated mechanisms control fates of multipotent progenitors in developing tissues. Here, we show that an essential PRC component, Ezh2, is expressed in epidermal progenitors, but diminishes concomitant with embryonic differentiation and with postnatal decline in proliferative activity. We show that Ezh2 controls proliferative potential of basal progenitors by repressing the Ink4A-Ink4B locus, and tempers the developmental rate of differentiation by preventing premature recruitment of AP1 transcriptional activator to the structural genes that are required for epidermal differentiation. Together, our studies reveal that PRCs control epigenetic modifications temporally and spatially in tissue-restricted stem cells by maintaining their proliferative potential and globally repressing undesirable differentiation programs, while selectively establishing a specific terminal differentiation program in a step-wise fashion.
Publication Title
Ezh2 orchestrates gene expression for the stepwise differentiation of tissue-specific stem cells.
Sample Metadata Fields
No sample metadata fields
View Samples- Homo sapiens
- 5 Downloadable Samples
- Affymetrix Human Transcriptome Array 2.0 (hta20)
Description
We demonstrate that the catalytic subunit of Polycomb Repressive Complex 2, EZH2, is targeted by the MELK-FOXM1 complex, which in turn promotes resistance to radiation in GSCs. Clinically, EZH2 and MELK are co-expressed in GBM and significantly induced in post-irradiation recurrent tumors whose expression inversely correlated with patient prognosis. Through gain-and loss-of-function study, our data show that MELK or FOXM1 contributes on GSC radioresistance by regulation of EZH2.
Publication Title
EZH2 protects glioma stem cells from radiation-induced cell death in a MELK/FOXM1-dependent manner.
Sample Metadata Fields
Specimen part, Cell line
View Samples- Homo sapiens
- 32 Downloadable Samples
IlluminaHiSeq3000
Description
We assessed global gene expression changes in 32 human glioblastoma specimens Overall design: Human mRNA profiles of 32 glioblastoma specimens, were obtained by sequencing on Illumina HiSeq 3000
Publication Title
Glioblastoma-infiltrated innate immune cells resemble M0 macrophage phenotype.
Sample Metadata Fields
No sample metadata fields
View Samples- Homo sapiens
- 19 Downloadable Samples
Affymetrix Human Genome U133A 2.0 Array (hgu133a2)
Description
This SuperSeries is composed of the SubSeries listed below.
Publication Title
Mesenchymal differentiation mediated by NF-κB promotes radiation resistance in glioblastoma.
Sample Metadata Fields
Specimen part, Treatment
View Samples- Homo sapiens
- 15 Downloadable Samples
- Affymetrix Human Genome U133A 2.0 Array (hgu133a2)
Description
SUMMARY Despite numerous genome-wide association studies involving glioblastoma (GBM), few therapeutic targets have been identified for this disease. Using patient derived glioma sphere cultures (GSCs), we have found that a subset of the proneural (PN) GSCs undergo transition to a mesenchymal (MES) state in a TNFa/NFkB dependent manner with an associated enrichment of CD44 sub-populations and radio-resistant phenotypes. To the contrary, MES GSCs exhibit constitutive NFkB activation, CD44 enrichment and radio-resistance. Patients whose tumors exhibit a higher MES metagene, increased expression of CD44, or activated NFkB were associated with poor radiation response and shorter survival. Our results indicate that NFkB activation mediated MES differentiation and radiation resistance presents an attractive therapeutic target for GBM.
Publication Title
Mesenchymal differentiation mediated by NF-κB promotes radiation resistance in glioblastoma.
Sample Metadata Fields
Specimen part
View Samples- Homo sapiens
- 4 Downloadable Samples
- Affymetrix Human Genome U133A 2.0 Array (hgu133a2)
Description
SUMMARY Despite numerous genome-wide association studies involving glioblastoma (GBM), few therapeutic targets have been identified for this disease. Using patient derived glioma sphere cultures (GSCs), we have found that a subset of the proneural (PN) GSCs undergo transition to a mesenchymal (MES) state in a TNFa/NFkB dependent manner with an associated enrichment of CD44 sub-populations and radio-resistant phenotypes. To the contrary, MES GSCs exhibit constitutive NFkB activation, CD44 enrichment and radio-resistance. Patients whose tumors exhibit a higher MES metagene, increased expression of CD44, or activated NFkB were associated with poor radiation response and shorter survival. Our results indicate that NFkB activation mediated MES differentiation and radiation resistance presents an attractive therapeutic target for GBM.
Publication Title
Mesenchymal differentiation mediated by NF-κB promotes radiation resistance in glioblastoma.
Sample Metadata Fields
Specimen part, Treatment
View Samples