Spatio-temporal evolution of the primary glioblastoma genome (aCGH)
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ABSTRACT:
ORGANISM(S): Homo sapiens
PROVIDER: GSE63035 | GEO | 2015/10/06
SECONDARY ACCESSION(S): PRJNA266484
REPOSITORIES: GEO
Similar Datasets
Project description:Tumor recurrence following treatment is the major cause of mortality for glioblastoma multiforme (GBM) patients. Thus, insights on the evolutionary process at recurrence are critical for improved patient care. Here, we describe our genomic analyses of 38 GBM patients with the initial and recurrent tumor specimens for each individual. A substantial divergence in the landscape of driver alterations was associated with distant appearance of a recurrent tumor from the initial tumor, suggesting that the genomic profile of the initial tumor can mislead targeted therapies for the distally recurred tumor. In addition, in contrast to IDH1-mutated gliomas, IDH1-wild-type primary GBMs rarely developed hypermutation following temozolomide (TMZ) treatment, indicating low risk of TMZ-induced hypermutation for these patients under the standard regimen.
| EGAS00001001041 | EGA
Project description:In this study, we developed an extensive dataset for a GBM case via the generation of polyclonal and monoclonal glioma stem cell lines from initial diagnosis, as well as from multiple sections of distant tumor locations of the deceased patient’s brain following tumor recurrence. Our analyses revealed the tissue-wide expansion of a new clone in the recurrent tumor as well as chromosome 7 gain and chromosome 10 loss as repeated genomic events in primary and recurrent disease. Moreover, chromosome 7 gain and chromosome 10 loss produced similar alterations in mRNA expression profiles in primary and recurrent tumors despite possessing other highly heterogeneous and divergent genomic alterations between the tumors. We identified ETV1 and CDK6 as putative candidate genes, and NFKB (complex), IL1B, IL6, Akt and VEGF as potential signaling regulators, as potentially central downstream effectors of chr7 gain and chr10 loss. Finally, the differences caused by the transcriptomic shift following gain of chromosome 7 and loss of chromosome 10 were consistent with those generally seen in GBM samples compared to normal brain in large-scale patient-tumor data sets.
2017-10-01 | GSE101113 | GEO
Project description:In this study, we developed an extensive dataset for a GBM case via the generation of polyclonal and monoclonal glioma stem cell lines from initial diagnosis, as well as from multiple sections of distant tumor locations of the deceased patient’s brain following tumor recurrence. Our analyses revealed the tissue-wide expansion of a new clone in the recurrent tumor as well as chromosome 7 gain and chromosome 10 loss as repeated genomic events in primary and recurrent disease. Moreover, chromosome 7 gain and chromosome 10 loss produced similar alterations in mRNA expression profiles in primary and recurrent tumors despite possessing other highly heterogeneous and divergent genomic alterations between the tumors. We identified ETV1 and CDK6 as putative candidate genes, and NFKB (complex), IL1B, IL6, Akt and VEGF as potential signaling regulators, as potentially central downstream effectors of chr7 gain and chr10 loss. Finally, the differences caused by the transcriptomic shift following gain of chromosome 7 and loss of chromosome 10 were consistent with those generally seen in GBM samples compared to normal brain in large-scale patient-tumor data sets.
2017-10-01 | GSE101110 | GEO
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.
2012-10-16 | E-GEOD-36245 | biostudies-arrayexpress
Project description:Recurrent glioblastoma (GBM) has a grim prognosis, though MGMT promoter methylation and IDH mutation provide a significant survival advantage. The product of IDH mutation, 2-hydroxyglutarate, increases global DNA methylation by inhibiting demethylases. While lower-grade IDH-mutant gliomas demonstrate increased methylation as a result of this process, DNA becomes relatively hypomethylated during progression from low-grade glioma to secondary (IDH-mutant) GBM. Here we show that global DNA hypomethylation also occurs during primary (IDH-wild type) GBM recurrence. Moreover, in a phase I trial of 14 patients with recurrent (IDH-wild type) GBM, we targeted DNA hypomethylation using a methyl donor treatment. In autopsied tumors from patients treated, we observed a global increase in DNA methylation compared to initial tumor. These results suggest that hypomethylation is a marker for recurrence, and its reprogramming represents a potential therapeutic vulnerability.
2021-12-31 | GSE111627 | GEO
Project description:Introduction: Glioblastoma (GBM) is a lethal brain tumor without effective treatment options. Here, we sought to characterize longitudinal tumor immune microenvironment (iTME) changes in order to find potential actionable targets to prevent GBM-induced immune evasion mechanisms. This study included 15 patient-matched treatment-naïve (primary, pGBM, WHO grade 4) and recurrent (rGBM) IDH1 wild type tumors. Methods:Extracted RNA and proteins from fresh frozen tumor samples from matched pGBM and rGBM were profiled via transcriptomics and proteomics, respectively. Paired formalin-fixed paraffin-embedded tumor samples were processed for spatial transcriptomics analysis.Results: Differentially expressed genes and proteins between pGBM and rGBM were involved in pathways responsible for synapse development and myelination which have been shown to play a role in GBM recurrence. By categorizing patients into short and long time-to-relapse (STTR vs LTTR), and by correlating TTR with gene expression, we detected genes positively or negatively associated with tumor relapse. Expression of FCG receptor and complement system genes such as FCGR1A (CD64), FCGR3A (CD16a) and the complement C3 were negatively correlated with STTR, whereas high expression of DNMT1/3A, and SMARCA4, involved in DNA methylation, were positively correlated with LTTR. Spatial transcriptomic analysis of the tumor cells compartment defined by GFAP expression showed enrichment in the proportion of oligodendrocytes in recurrent tumors in rGBM, whereas CD64-positive myeloid cell compartment showed a switch of quiescent to activated microglia, appearance of B cells and a reduction in macrophage proportion in recurrent tumors with STTR. Conclusion: Our results uncover a role of CD64-expressing myeloid cells, mostly activated microglia, in GBM recurrence and suggest that interfering with these cells may represent a new therapeutic option for preventing GBM relapse.
2024-11-18 | GSE254145 | GEO
Project description:Background Despite maximal therapy with surgery, chemotherapy and radiotherapy, glioblastoma multiforme (GBM) patients have a median survival of only 15 months. Almost all patients inevitably experience symptomatic tumor recurrence. A hallmark of this tumor type is the large heterogeneity between patients and within tumors itself which relate to failure of standardized tumor treatment. In this study, tissue samples of paired primary and recurrent GBM tumors were investigated to identify individual factors related to tumor progression. Methods Paired primary and recurrent GBM tumor tissues from 8 patients were investigated with a multi-omics approach using transcriptomics, proteomics and phosphoproteomics. Results In the studied patient cohort, large variations between and within patients are observed for all omics analyses. A few pathways affected at the different omics levels partly overlapped if patients are analyzed at the individual level, such as synaptogenesis (containing the SNARE complex) and cholesterol metabolism. Phosphoproteomics revealed increased STMN1(S38) phosphorylation that relates to ERBB4 signaling. A pathway tool has been developed to visualize and compare the different omics datasets per patient and showed potential therapeutic drugs, such as abobotulinumtoxina and afatinib, that target these affected pathways. Afatinib targeting ERBB4 signaling is currently in clinical trials for GBM. Conclusions Large variation on all omics levels exist between and within GBM patients. Therefore, it will be rather unlikely to find a drug treatment that would fit all patients. Instead a multi-omics approach can be used to identify affected pathways on the individual patient level and select potential treatment options.
2020-11-17 | PXD017952 | Pride
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.
2012-10-16 | E-GEOD-36278 | biostudies-arrayexpress
Project description:Background: Glioblastoma (GBM) is the most aggressive and currently incurable brain tumor with a median survival of one year in adult patients. Elucidating novel transcriptomic and epigenetic contributors to the molecular heterogeneity underlying its aggressiveness may lead to improved clinical outcomes. Methods: To identify GBM-associated 5-hydroxymethylcytosine (5hmC) and transcriptomic features as well as their cross-talks, genome-wide 5hmC and transcriptomic profiles of tissue samples from 61 patients with GBM and 9 normal controls were obtained for differential and co-regulation/co-modification analyses. Prognostic models on overall survival (OS) based on transcriptomic features and the 5hmC modifications summarized over genic regions (promoters, gene bodies) and brain-derived histone marks were developed using machine learning algorithms. Results: Despite global reduction, the majority of differential 5hmC features showed higher modification levels in GBM tumors as compared to normal controls. In addition, the bi-directional correlations between 5hmC modifications over promoter regions or gene bodies and gene expression were greatly disturbed in GBM tumors regardless of IDH1 mutation status. Phenotype-associated co-regulated 5hmC-5hmC modules and 5hmC-mRNA modules not only are enriched with different molecular pathways that are indicative of the pathogenesis of GBM, but also are of prognostic significance comparable to IDH1 mutation status. Lastly, the best-performing 5hmC model can predict patient survival at a much higher accuracy (c-index = 74%) when compared to conventional prognostic factor IDH1 (c-index = 57%), capturing the molecular characteristics of tumors that are independent of IDH1 mutation status and gene expression-based molecular subtypes. Conclusions: The 5hmC-based prognostic model offers a robust tool to predict survival in GBM patients, outperforming existing prognostic factors such as IDH1 mutations. The crosstalk between 5hmC and gene expression revealed another layer of complexity underlying the molecular heterogeneity in GBM, offering opportunities for identifying novel therapeutic targets.
2023-08-23 | GSE196533 | GEO
Project description:Introduction: Glioblastoma (GBM) is a lethal brain tumor without effective treatment options. Here, we sought to characterize longitudinal tumor immune microenvironment (iTME) changes in order to find potential actionable targets to prevent GBM-induced immune evasion mechanisms. This study included 15 patient-matched treatment-naïve (primary, pGBM, WHO grade 4) and recurrent (rGBM) IDH1 wild type tumors. Methods: Extracted RNA and proteins from fresh frozen tumor samples from matched pGBM and rGBM were profiled via transcriptomics and proteomics, respectively. Paired formalin-fixed paraffin-embedded tumor samples were processed for spatial transcriptomics analysis. Results: Differentially expressed genes and proteins between pGBM and rGBM were involved in pathways responsible for synapse development and myelination which have been shown to play a role in GBM recurrence. By categorizing patients into short and long time-to-relapse (STTR vs LTTR), and by correlating TTR with gene expression, we detected genes positively or negatively associated with tumor relapse. Expression of FCG receptor and complement system genes such as FCGR1A (CD64), FCGR3A (CD16a) and the complement C3 were negatively correlated with STTR, whereas high expression of DNMT1/3A, and SMARCA4, involved in DNA methylation, were positively correlated with LTTR. Spatial transcriptomic analysis of the tumor cells compartment defined by GFAP expression showed enrichment in the proportion of oligodendrocytes in recurrent tumors in rGBM, whereas CD64-positive myeloid cell compartment showed a switch of quiescent to activated microglia, appearance of B cells and a reduction in macrophage proportion in recurrent tumors with STTR. Conclusion: Our results uncover a role of CD64-expressing myeloid cells, mostly activated microglia, in GBM recurrence and suggest that interfering with these cells may represent a new therapeutic option for preventing GBM relapse.
2024-11-18 | GSE254874 | GEO