Homo sapiens
Ontology highlight
ABSTRACT:
PROVIDER: PRJNA290069 | ENA |
REPOSITORIES: ENA
Similar Datasets
Project description:Gain-of-function IDH mutations define major clinical and prognostic classes of gliomas. Mutant IDH protein produces a novel onco-metabolite, 2-hydroxyglutarate (2-HG), that interferes with iron-dependent hydroxylase enzymes, including the TET family of 5'-methylcytosine hydroxylases. TET enzymes are critical for the dynamic regulation of DNA methylation. IDH mutant gliomas thus manifest a CpG island methylator phenotype (G-CIMP), though the functional significance of this altered epigenetic state remains unclear. Here we show that IDH1 mutant gliomas exhibit hyper-methylation at CTCF binding sites, leading to reduced binding of this methylation-sensitive insulator protein. Loss of CTCF binding is associated with a loss of insulation between topological domains and aberrant gene activation. We specifically demonstrate that loss of CTCF at a domain boundary permits a constitutive enhancer to aberrantly interact with the receptor tyrosine kinase gene PDGFRA, a prominent glioma oncogene. Treatment of IDH mutant gliomaspheres with demethylating agent partially restores insulator function and reduces PDGFRA expression. Conversely, CRISPR-mediated disruption of the CTCF binding sequence in IDH wildtype gliomaspheres induces PDGFRA expression and increases proliferation. Our study suggests that IDH mutations promote gliomagenesis by disrupting chromosomal topology and allowing aberrant regulatory interactions that induce oncogene expression. CTCF occupancy characterization and histone H3K27 acetylation profiling in IDH1 mutant and wild-type glioma patient specimens and culture models. ChIP-seq raw data is to be made available through dbGaP (controlled access) due to patient privacy concerns.
2015-12-23 | E-GEOD-70991 | biostudies-arrayexpress
Project description:Gain-of-function IDH mutations define major clinical and prognostic classes of gliomas. Mutant IDH protein produces a novel onco-metabolite, 2-hydroxyglutarate (2-HG), that interferes with iron-dependent hydroxylase enzymes, including the TET family of 5'-methylcytosine hydroxylases. TET enzymes are critical for the dynamic regulation of DNA methylation. IDH mutant gliomas thus manifest a CpG island methylator phenotype (G-CIMP), though the functional significance of this altered epigenetic state remains unclear. Here we show that IDH1 mutant gliomas exhibit hyper-methylation at CTCF binding sites, leading to reduced binding of this methylation-sensitive insulator protein. Loss of CTCF binding is associated with a loss of insulation between topological domains and aberrant gene activation. We specifically demonstrate that loss of CTCF at a domain boundary permits a constitutive enhancer to aberrantly interact with the receptor tyrosine kinase gene PDGFRA, a prominent glioma oncogene. Treatment of IDH mutant gliomaspheres with demethylating agent partially restores insulator function and reduces PDGFRA expression. Conversely, CRISPR-mediated disruption of the CTCF binding sequence in IDH wildtype gliomaspheres induces PDGFRA expression and increases proliferation. Our study suggests that IDH mutations promote gliomagenesis by disrupting chromosomal topology and allowing aberrant regulatory interactions that induce oncogene expression.
2015-12-23 | GSE70991 | GEO
Project description:Isocitrate dehydrogenase (IDH)-mutant gliomas have distinctive metabolic and biological traits that may render them susceptible to targeted treatments. Here, by conducting a high-throughput drug screen, we pinpointed a specific susceptibility of IDH-mutant gliomas to zotiraciclib (ZTR). ZTR exhibited selective growth inhibition across multiple IDH-mutant glioma in vitro and in vivo models. Mechanistically, ZTR at low doses suppressed CDK9 and RNA Pol II phosphorylation in IDH-mutant cells, disrupting mitochondrial function and NAD+ production, causing oxidative stress.,. Integrated biochemical profiling of ZTR kinase targets and transcriptomics unveiled that ZTR-induced bioenergetic failure was linked to the suppression of PIM kinase activity. We posit that the combination of mitochondrial dysfunction and an inability to adapt to oxidative stress resulted in significant cell death upon ZTR treatment, ultimately increasing the therapeutic vulnerability of IDH-mutant gliomas. These findings prompted a clinical trial evaluating ZTR in IDH-mutant gliomas towards precision medicine (NCT05588141).
2024-12-31 | GSE252245 | GEO
Project description:Affymetrix OncoScan data for IDH and TP53 mutant gliomas
| PRJNA371737 | ENA
Project description:Background: Isocitrate dehydrogenase mutant (IDH-mut) glioma represents a distinct subtype of adult glioma. Although IDH-mut glioma displays slightly better prognosis among adult gliomas, these tumors are still incurable largely due to the lack of effective treatments. Targeting SHP2 has been shown to be a promising therapeutic approach in various types of malignancies, and our previous research demonstrated its efficacy against IDH wildtype (WT) glioblastoma (GBM). However, whether IDH-mutant gliomas are responsive to SHP2 inhibition remains unknown. Methods: Bioinformatic and biological analyses revealed increased expression and activation of PDGFRα-SHP2-ERK pathway in clinical IDH-mutant gliomas and patient-derived IDH-mut glioma stem-like cells (GSCs). Therapeutic effects of a SHP2 inhibitor on inhibition of the PDGFRα-SHP2-ERK signaling and tumorigenicity of IDH-mut GSCs, individually or in combination with radiation therapy (RT) were assessed by cell growth, glioma sphere formation, cell differentiation, flow cytometry, immunoblotting, orthotopic brain tumor xenograft, bioluminescent tracking, and immunohistochemistry. Results: We found a marked increase in PDGFRα expression in clinical IDH-mutant gliomas and IDH-mut GSCs, leading to the activation of the downstream SHP2-ERK pathway. Treatment with a blood-brain barrier-penetrable SHP2 inhibitor, SHP099 significantly inhibited GSC tumorigenic properties in vitro and in vivo by impeding SHP2-ERK axis and inducing cellular differentiation. Additionally, SHP099 treatment synergistically enhanced cytotoxicity of RT on IDH-mut GSCs in vitro and in orthotopic glioma xenografts, the standard treatment for IDH-mut glioma. Mechanistically, the PDGFRα -SHP2-ERK axis is activated in IDH-mut gliomas while radiation activates the SHP2-ERK pathway. Targeting SHP2 suppressed the activated ERK signaling thereby enhancing cytotoxicity of RT against IDH-mut gliomas. Conclusion: Targeting SHP2 in combination with RT for treating IDH-mut glioma displays promising therapeutic efficacy through suppressing a preferentially activated SHP2-ERK axis in IDH-mut gliomas.
2025-09-19 | GSE277548 | GEO
Project description:Adult diffuse gliomas are the deadliest brain tumours including IDH-wildtype glioblastomas of worst prognosis and diffuse low grade IDH-mutant astrocytomas and oligodendrogliomas. These glial tumours display distinct tumoral cell population defeating current therapies. Our group has previously unveiled the role of NOTCH signalling in glioblastoma cell plasticity and in the conversion of oligodendrocytic-like to astrocytic-like tumoral cells in IDH-mutant low-grade gliomas which escalate inevitably to higher grade malignant gliomas. To gain insight into signalling pathways regulating glioma cell plasticity and malignancy, we focused our work on endothelin signalling including endothelin peptide ligands (ET-1, ET-2, ET-3) binding to G-protein coupled endothelin receptors A and B (EDNRA, EDNRB). Here, using glioma patient samples and glioma patient-derived cell lines, we showed that endothelin reduces glioma cell proliferation while increasing migration initiating a proneural to mesenchymal transition. Mechanistically, EDNRB activation led to IP3-dependent calcium mobilization, apamin-sensitive KCNN2/KCNN3 potassium currents and phosphorylation of ERK1/2 and STAT3 in glioma cells. Finally, we studied endothelin receptor regulation by tumoral microenvironment stimuli highlighting a role for EDNRA induced by NOTCH1 and hypoxia in perivascular hypoxic area in glioblastoma. Altogether, this study demonstrates endothelin signalling as a key player in mesenchymal transformation of diffuse IDH-mutant gliomas and glioblastomas.
2026-03-11 | PXD065902 | Pride
Project description:Recent single-cell transcriptomic studies report that IDH-mutant gliomas share a common hierarchy of cellular phenotypes, independent of genetic subtype. However, the genetic differences between IDH-mutant glioma subtypes are prognostic, predictive of response to chemotherapy, and correlate with distinct tumor microenvironments. To reconcile these findings, we profiled 22 human IDH-mutant gliomas via single-cell assay for transposase-accessible chromatin (scATAC-seq). We determined the cell-type specific differences in transcription-factor expression and associated regulatory grammars between IDH-mutant glioma subtypes. We find that while IDH-mutant gliomas do share a common distribution of cell types, there are significant differences in the expression and targeting of transcription factors that regulate glial identity and cytokine elaboration. We knocked out the chromatin-remodeler ATRX, which suffers loss-of-function alterations in most IDH-mutant astrocytomas, in an IDH-mutant immunocompetent intracranial murine model. We find that both human ATRX-mutant gliomas and murine ATRX-knockout gliomas are more heavily infiltrated by immunosuppressive monocytic-lineage cells derived from circulation than ATRX-intact gliomas, in an IDH-mutant background. ATRX knockout in murine glioma recapitulates gene expression and open-chromatin signatures that are specific to human ATRX-mutant astrocytomas, including drivers of astrocytic lineage and immune-cell chemotaxis. ATRX knockout in murine glioma recapitulates gene expression and open chromatin signatures that are specific to human ATRX-mutant astrocytomas, including drivers of astrocytic lineage and immune-cell chemotaxis. Through single-cell cleavage under targets and tagmentation assays and meta-analysis of public data, we show that ATRX loss leads to a global depletion in CCCTC-binding factor association with DNA, gene dysregulation along associated chromatin loops, and protection from therapy-induced senescence.
2021-10-20 | GSE155430 | GEO
Project description:Epigenetic lesions that disrupt gene regulatory elements and expression are increasingly recognized as pervasive drivers of human cancers. However, we currently lack the in vitro and in vivo models required to functionally validate such lesions and their tumorigenic impact. Here we model aberrations that arise in Isocitrate Dehydrogenase mutant (IDHmut) lower-grade gliomas, which exhibit profound DNA hypermethylation. We initially focus on a CTCF insulator downstream of the PDGFRA oncogene that is recurrently disrupted in IDHmut gliomas. We demonstrate that disruption of the syntenic insulator in mouse oligodendrocyte-progenitor cells (OPCs) allows an OPC-specific enhancer to contact and induce PDGFRA, thereby increasing proliferation. In contrast, insulator disruption did not affect PDGFRA expression in neural progenitor cells (NPCs), which lack the enhancer. We also model a second recurrent epigenetic lesion in IDHmut gliomas, the methylation-dependent silencing of the CDKN2A tumor suppressor. We show that inactivation of CDKN2A/p19ARF by de novo promoter methylation or mutation drives OPC proliferation and synergizes with PDGFRA insulator loss. Finally, we use lentiviruses to coordinately inactivate the PDGFRA insulator and CDKN2A in mouse corpus callosum, resulting in low-grade gliomagenesis in vivo. Our study recapitulates recurrent epigenetic lesions in mouse models and demonstrates that combination of PDGFRA activation and CDKN2A silencing can transform OPCs in vitro and drive gliomagenesis in vivo.
2023-07-25 | GSE225732 | GEO
Project description:Adult-type diffuse gliomas comprise IDH-mutant astrocytomas, IDH-mutant 1p/19q codeleted oligodendrogliomas (ODG), and IDH-wildtype glioblastomas (GBM). GBM display genome instability, which may result from two genetic events leading to massive chromosome alterations: chromothripsis (CT) and whole-genome duplication (WGD). The better prognosis of the latter may be related to their genome stability compared to GBM. Pangenomic profiles of 297 adult diffuse gliomas were analyzed at initial diagnosis using SNP arrays, including 192 GBM and 105 IDH-mutant gliomas (61 astrocytomas and 44 ODG). Tumor ploidy was assessed with Genome Alteration Print and CT events with CTLPScanner and through manual screening.
2024-12-24 | E-MTAB-13542 | biostudies-arrayexpress
Project description:IDH and TP53 mutant gliomas are high recurrent tumor, and thus we aimed to detect malignant and recurent factors in this genetic type of gliomas
2017-09-01 | GSE94652 | GEO