Project description:Glioblastoma (GBM) is an incurable brain tumor carrying a dismal prognosis, which displays considerable heterogeneity. We have recently identified recurrent H3F3A mutations affecting two critical positions of histone H3.3 (K27, G34) in one-third of pediatric GBM. Here we show that each of these H3F3A mutations defines an epigenetic subgroup of GBM with a distinct global methylation pattern, and are mutually exclusive with IDH1 mutation (characterizing a CpG-Island Methylator Phenotype (CIMP) subgroup). Three further epigenetic subgroups were enriched for hallmark genetic events of adult GBM (EGFR amplification, CDKN2A/B deletion) and/or known transcriptomic signatures. We also demonstrate that the two H3F3A mutations give rise to GBMs in separate anatomic compartments, with differential regulation of OLIG1/2 and FOXG1, possibly reflecting different cellular origins. To further dissect the biological differences between epigenetic glioblastoma subgroups, we looked at the transcriptomic profiles of glioblastoma samples. 46 glioblastoma samples from patients of various ages were selected for RNA extraction and hybridization on Affymetrix Affymetrix Human Genome U133 Plus 2.0 Arrays.
Project description:Glioblastoma (GBM) is an incurable brain tumor carrying a dismal prognosis, which displays considerable heterogeneity. We have recently identified recurrent H3F3A mutations affecting two critical positions of histone H3.3 (K27, G34) in one-third of pediatric GBM. Here we show that each of these H3F3A mutations defines an epigenetic subgroup of GBM with a distinct global methylation pattern, and are mutually exclusive with IDH1 mutation (characterizing a CpG-Island Methylator Phenotype (CIMP) subgroup). Three further epigenetic subgroups were enriched for hallmark genetic events of adult GBM (EGFR amplification, CDKN2A/B deletion) and/or known transcriptomic signatures. We also demonstrate that the two H3F3A mutations give rise to GBMs in separate anatomic compartments, with differential regulation of OLIG1/2 and FOXG1, possibly reflecting different cellular origins. To further dissect the biological differences between epigenetic glioblastoma subgroups, we looked at the transcriptomic profiles of glioblastoma samples.
Project description:Glioblastoma (GBM) is an incurable brain tumor carrying a dismal prognosis, which displays considerable heterogeneity. We have recently identified recurrent H3F3A mutations affecting two critical positions of histone H3.3 (K27, G34) in one-third of pediatric GBM. Here we show that each of these H3F3A mutations defines an epigenetic subgroup of GBM with a distinct global methylation pattern, and are mutually exclusive with IDH1 mutations (characterizing a CpG-Island Methylator Phenotype (CIMP) subgroup). Three further epigenetic subgroups were enriched for hallmark genetic events of adult GBM (EGFR amplification, CDKN2A/B deletion) and/or known transcriptomic signatures. We also demonstrate that the two H3F3A mutations give rise to GBMs in separate anatomic compartments, with differential regulation of OLIG1/2 and FOXG1, possibly reflecting different cellular origins. We identified six epigenetic and biological GBM subgroups displaying distinct global DNA methylation patterns, which harbor unique hotspot mutations, DNA copy-number alterations, and transcriptomic patterns. We investigated a subset of childhood (n=59) and adult GBMs (n=77) using the Illumina 450k methylation array. Six non-neoplastic brain tissue samples are included as controls.
Project description:Glioblastoma (GBM) is an incurable brain tumor carrying a dismal prognosis, which displays considerable heterogeneity. We have recently identified recurrent H3F3A mutations affecting two critical positions of histone H3.3 (K27, G34) in one-third of pediatric GBM. Here we show that each of these H3F3A mutations defines an epigenetic subgroup of GBM with a distinct global methylation pattern, and are mutually exclusive with IDH1 mutations (characterizing a CpG-Island Methylator Phenotype (CIMP) subgroup). Three further epigenetic subgroups were enriched for hallmark genetic events of adult GBM (EGFR amplification, CDKN2A/B deletion) and/or known transcriptomic signatures. We also demonstrate that the two H3F3A mutations give rise to GBMs in separate anatomic compartments, with differential regulation of OLIG1/2 and FOXG1, possibly reflecting different cellular origins. We identified six epigenetic and biological GBM subgroups displaying distinct global DNA methylation patterns, which harbor unique hotspot mutations, DNA copy-number alterations, and transcriptomic patterns.
Project description:Ependymoma (EPN) is the third most common central nervous system (CNS) tumor in childhood and, recently, has been classified in nine robust molecular subgroups (Pajtler et al., 2015). However, molecular and clinical features of pediatric EPNs from Brazilian cohorts remain unexplored. Herein, we aimed to analyze the gene expression profile among three different molecular subgroups: ST-EPN-RELA, ST-EPN-YAP1 and PF-EPN-A.
Project description:Pediatric high-grade gliomas (pHGGs) harboring the K27M mutation of H3F3A (histone H3.3) are characterized by global reduction of the repressive histone mark H3K27me3 and DNA hypomethylation. Analysis of K27M-induced changes on H3K27me3 occupancy and DNA methylation at differentially expresed genes (K27M vs. wild-type H3.3) in primary pHGG tumor samples. 22 glioblastoma samples from pHGG patients were selected for RNA extraction and hybridization on Affymetrix Affymetrix Human Genome U133 Plus 2.0 Arrays. Expression profiling data of 17 pHHGs are part of our previous study (GSE36245 or GSE34824).
Project description:Glioblastoma (GBM) is an incurable brain tumor carrying a dismal prognosis, which displays considerable heterogeneity. We have recently identified recurrent H3F3A mutations affecting two critical positions of histone H3.3 (K27, G34) in one-third of pediatric GBM. Here we show that each of these H3F3A mutations defines an epigenetic subgroup of GBM with a distinct global methylation pattern, and are mutually exclusive with IDH1 mutation (characterizing a CpG-Island Methylator Phenotype (CIMP) subgroup). Three further epigenetic subgroups were enriched for hallmark genetic events of adult GBM (EGFR amplification, CDKN2A/B deletion) and/or known transcriptomic signatures. We also demonstrate that the two H3F3A mutations give rise to GBMs in separate anatomic compartments, with differential regulation of OLIG1/2 and FOXG1, possibly reflecting different cellular origins. To further dissect the biological differences between epigenetic glioblastoma subgroups, we looked at the transcriptomic profiles of glioblastoma samples. 46 glioblastoma samples from patients of various ages were selected for RNA extraction and hybridization on Affymetrix Affymetrix Human Genome U133 Plus 2.0 Arrays.
Project description:The neural behavior of glioblastoma, including the formation of tumor microtubes and synaptic circuitry, is increasingly understood to be pivotal for disease manifestation (Osswald et al. 2015; Venkatesh et al. 2015; Weil et al. 2017; Venkataramani et al. 2019; Venkatesh et al. 2019; Alcantara Llaguno et al. 2019; Venkataramani et al. 2022). Nonetheless, the few approved treatments for glioblastoma target its oncological nature, while its neural vulnerabilities remain incompletely mapped and clinically unexploited. Here, we systematically survey the neural molecular dependencies and cellular heterogeneity across 27 glioblastoma patients and diverse model systems. In patient tumor samples taken directly after surgery, we identify a spectrum of neural stem cell morphologies indicative of poor prognosis, and discover a set of repurposable neuroactive drugs with unexpected and consistent anti-glioma efficacy. Glioblastoma cells exhibit functional dependencies on highly expressed drug targets including neurological ion channels and receptors, while interpretable molecular machine learning reveals downstream convergence on secondary drug targets (COSTAR) involving AP-1-driven tumor suppression. COSTAR enables in silico drug screening on >1 million compounds that are validated with high accuracy. Multi-omic profiling of drug-treated glioblastoma cells confirms rapid Ca2+-driven AP-1 pathway induction to represent a tumor-intrinsic vulnerability at the intersection of oncogenesis and neural activity-dependent signaling. Finally, the consistent anti-glioma activity across patients and model systems is epitomized by the antidepressant Vortioxetine, which synergizes in vivo with approved glioblastoma chemotherapies. In all, our global analysis reveals that the neural vulnerabilities of glioblastoma converge on an AP-1 mediated gene regulatory network with direct translatable potential.