Delineation of Two Clinically and Molecularly Distinct Subgroups of Posterior Fossa Ependymoma
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ABSTRACT:
ORGANISM(S): Homo sapiens
SUBMITTER: Christopher Stephen
PROVIDER: S-ECPF-GEOD-27279 | biostudies-other |
REPOSITORIES: biostudies-other
Similar Datasets
Project description:Despite the histological similarity of ependymomas from throughout the neuroaxis, the disease likely comprises multiple independent entities, each with a distinct molecular pathogenesis. Transcriptional profiling of two large independent cohorts of ependymoma reveals the existence of two demographically, transcriptionally, genetically, and clinically distinct groups of posterior fossa (PF) ependymomas. Group A patients are younger, have laterally located tumors with a balanced genome, and are much more likely to exhibit recurrence, metastasis at recurrence, and death compared with Group B patients. Identification and optimization of immunohistochemical (IHC) markers for PF ependymoma subgroups allowed validation of our findings on a third independent cohort, using a human ependymoma tissue microarray, and provides a tool for prospective prognostication and stratification of PF ependymoma patients.
| S-EPMC4154494 | biostudies-literature
Project description:Despite histological similarity of ependymomas from throughout the neuraxis, the disease likely comprises multiple independent entities, each with a distinct molecular pathogenesis. Transcriptional profiling of two large independent cohorts of ependymomas reveals the existence of two demographically, transcriptionally, genetically and clinically distinct groups of posterior fossa (PF) ependymoma. Group A patients are younger, have laterally located tumors with a balanced genome, and are much more likely to exhibit recurrence, metastasis, and death as compared to Group B patients. Identification and optimization of immunohistochemical markers for PF ependymoma subgroups allowed validation of our findings on a third group of independent ependymomas using a human ependymoma tissue microarray, and provides a tool for prospective prognostication and stratification of PF ependymoma patients. This SuperSeries is composed of the following subset Series: GSE27283: Human ependymoma samples [expression] GSE27286: Human ependymoma samples, Subgrouping [aCGH - German Cancer Research Center human 33K BAC array] Refer to individual Series
2011-08-14 | E-GEOD-27287 | biostudies-arrayexpress
Project description:Gene expression (mRNA) profiling of human ependymomas Despite the histological similarity of ependymomas from throughout the neuraxis, the disease likely comprises multiple independent entities, each with a distinct molecular pathogenesis. Transcriptional profiling of two large independent cohorts of ependymoma reveals the existence of two demographically, transcriptionally, genetically, and clinically distinct groups of posterior fossa (PF) ependymoma. Group-A patients are younger, have laterally located tumors with a balanced genome, and are much more likely to exhibit recurrence, secondary metastasis, and death as compared to Group-B patients. Identification and optimization of immunohistochemical markers for PF ependymoma subgroups allowed validation of our findings on a third independent group of tumors using a human ependymoma tissue microarray, and provides a tool for prospective prognostication and stratification of PF ependymoma patients. We analyzed 102 primary ependymomas on the Affymetrix Exon 1.0ST platform (Gene Level).
2011-08-14 | E-GEOD-27279 | biostudies-arrayexpress
Project description:Despite histological similarity of ependymomas from throughout the neuraxis, the disease likely comprises multiple independent entities, each with a distinct molecular pathogenesis. Transcriptional profiling of two large independent cohorts of ependymomas reveals the existence of two demographically, transcriptionally, genetically and clinically distinct groups of posterior fossa (PF) ependymoma. Group A patients are younger, have laterally located tumors with a balanced genome, and are much more likely to exhibit recurrence, metastasis, and death as compared to Group B patients. Identification and optimization of immunohistochemical markers for PF ependymoma subgroups allowed validation of our findings on a third group of independent ependymomas using a human ependymoma tissue microarray, and provides a tool for prospective prognostication and stratification of PF ependymoma patients. This SuperSeries is composed of the SubSeries listed below.
2011-08-15 | GSE27287 | GEO
Project description:Gene expression (mRNA) profiling of human ependymomas Despite the histological similarity of ependymomas from throughout the neuraxis, the disease likely comprises multiple independent entities, each with a distinct molecular pathogenesis. Transcriptional profiling of two large independent cohorts of ependymoma reveals the existence of two demographically, transcriptionally, genetically, and clinically distinct groups of posterior fossa (PF) ependymoma. Group-A patients are younger, have laterally located tumors with a balanced genome, and are much more likely to exhibit recurrence, secondary metastasis, and death as compared to Group-B patients. Identification and optimization of immunohistochemical markers for PF ependymoma subgroups allowed validation of our findings on a third independent group of tumors using a human ependymoma tissue microarray, and provides a tool for prospective prognostication and stratification of PF ependymoma patients.
2011-08-15 | GSE27279 | GEO
Project description:BackgroundPosterior fossa ependymoma (PFE) comprises 2 groups, PF group A (PFA) and PF group B (PFB), with stark differences in outcome. However, to the authors' knowledge, the long-term outcomes of PFA ependymoma have not been described fully. The objective of the current study was to identify predictors of survival and neurocognitive outcome in a large consecutive cohort of subgrouped patients with PFE over 30 years.MethodsDemographic, survival, and neurocognitive data were collected from consecutive patients diagnosed with PFE from 1985 through 2014 at the Hospital for Sick Children in Toronto, Ontario, Canada. Subgroup was assigned using genome-wide methylation array and/or immunoreactivity to histone H3 K27 trimethylation (H3K27me3).ResultsA total of 72 PFE cases were identified, 89% of which were PFA. There were no disease recurrences noted among patients with PFB. The 10-year progression-free survival rate for all patients with PFA was poor at 37.1% (95% confidence interval, 25.9%-53.1%). Analysis of consecutive 10-year epochs revealed significant improvements in progression-free survival and/or overall survival over time. This pertains to the increase in the rate of gross (macroscopic) total resection from 35% to 77% and the use of upfront radiotherapy increasing from 65% to 96% over the observed period and confirmed in a multivariable model. Using a mixed linear model, analysis of longitudinal neuropsychological outcomes restricted to patients with PFA who were treated with focal irradiation demonstrated significant continuous declines in the full-scale intelligence quotient over time with upfront conformal radiotherapy, even when correcting for hydrocephalus, number of surgeries, and age at diagnosis (-1.33 ± 0.42 points/year; P = .0042).ConclusionsData from a molecularly informed large cohort of patients with PFE clearly indicate improved survival over time, related to more aggressive surgery and upfront radiotherapy. However, to the best of the authors' knowledge, the current study is the first, in a subgrouped cohort, to demonstrate that this approach results in reduced neurocognitive outcomes over time.
| S-EPMC6508980 | biostudies-literature
Project description:Genomewide DNA methylation array profiling of nine posterior fossa ependymomas harboring activating mutations in ACVR1. Two samples clustered with the PFA subtype and demonstrated H3K27me3 loss by immunohistochemistry, while the remaining 7 showed retained H3K27me3 and formed a methylation cluster distinct from other ependymal tumors. For these previsouly unpublished cases, the Illumina Infinium EPIC 850k Human DNA Methylation Beadchip was used to obtain DNA methylation profiles across approximately 850,000 CpG sites of genomic DNA extracted from formalin-fixed, paraffin-embedded tumor tissue.
2022-05-01 | GSE196013 | GEO
Project description:Ependymomas are neuroepithelial tumors of the central nervous system (CNS), presenting in both adults and children but accounting for almost 10% of all pediatric CNS tumors and up to 30% of CNS tumors in children under 3 years (Bouffet et al., 2009; McGuire et al., 2009; Rodriguez et al., 2009). In children, most ependymomas arise in the posterior fossa, while most adult ependymomas present around the lower spinal cord and spinal nerve roots. Ependymomas display a wide range of morphological features, and several variants are listed in the World Health Organization (WHO) classification (Ellison et al., 2016). These variants are assigned to three WHO grades (I-III), but the clinical utility of this classification is acknowledged to be limited (Ellison et al., 2011). An increasing understanding of the genomic landscape of ependymoma and the discovery of distinct molecular groups by DNA methylation or gene expression profiling have begun to refine approaches to disease classification and prognostication, but have yet to be translated into clinical routine (Hoffman et al., 2014; Mack et al., 2014; Pajtler et al., 2017; Pajtler et al., 2015; Parker et al., 2014; Wani et al., 2012; Witt et al., 2011). Our comprehensive study of DNA methylation profiling across the entire disease demonstrated three molecular groups for each major anatomic compartment: supratentorial (ST), posterior fossa (PF), and spinal (SP) (Pajtler et al., 2015). In the ST compartment, two molecular groups (ST-EPN-RELA and ST-EPN-YAP1) align with tumors harboring specific genetic alterations, RELA and YAP1 fusion genes, which were initially discovered in a whole genome sequencing study (Parker et al., 2014). Among PF ependymomas, two of three molecular groups, PFA (PF-EPN-A) and PFB (PF-EPN-B), account for nearly all tumors; PF-SE tumors are rare, generally showing the morphology of a subependymoma (Pajtler et al., 2015). PFA tumors are found mainly in infants and young children (median age ≈ 3yrs) and have a relatively poor outcome, while PFB tumors are generally found in young adults (median age ≈ 30yrs) and are associated with a better prognosis (Pajtler et al., 2015; Witt et al., 2011). PFA tumors show few copy number alterations (CNAs), while PFB tumors harbor multiple CNAs that tend to affect entire chromosomes. While recurrent structural variants (SVs) are found in ST ependymomas, recurrent SVs or other mutations, such as single nucleotide variants (SNVs) and insertions or deletions (indels), have not been identified in PF ependymomas to date (Mack et al., 2014; Parker et al., 2014).
2018-06-26 | GSE104210 | GEO
Project description:Imaging descriptions of posterior fossa ependymoma in children have focused on magnetic resonance imaging (MRI) signal and local anatomic relationships with imaging location only recently used to classify these neoplasms. We developed a quantitative method for analyzing the location of ependymoma in the posterior fossa, tested its effectiveness in distinguishing groups of tumors, and examined potential associations of distinct tumor groups with treatment and prognostic factors.Pre-operative MRI examinations of the brain for 38 children with histopathologically proven posterior fossa ependymoma were analyzed. Tumor margin contours and anatomic landmarks were manually marked and used to calculate the centroid of each tumor. Landmarks were used to calculate a transformation to align, scale, and rotate each patient's image coordinates to a common coordinate space. Hierarchical cluster analysis of the location and morphological variables was performed to detect multivariate patterns in tumor characteristics. The ependymomas were also characterized as "central" or "lateral" based on published radiological criteria. Therapeutic details and demographic, recurrence, and survival information were obtained from medical records and analyzed with the tumor location and morphology to identify prognostic tumor characteristics.Cluster analysis yielded two distinct tumor groups based on centroid location The cluster groups were associated with differences in PFS (p = .044), "central" vs. "lateral" radiological designation (p = .035), and marginally associated with multiple operative interventions (p = .064).Posterior fossa ependymoma can be objectively classified based on quantitative analysis of tumor location, and these classifications are associated with prognostic and treatment factors.
| S-EPMC4967400 | biostudies-literature
Project description:BACKGROUND:5-Hydroxymethylcytosine (5hmC) is a novel epigenetic mark and may be involved in the mechanisms of tumorigenesis and malignant transformation. However, the role of 5hmC in ependymoma, the third most common brain tumor in children, remains unclear. The aim of this study sought to identify the characterization of 5hmC levels in pediatric posterior fossa ependymoma and to evaluate whether 5hmC levels could be a potential factor to predict clinical outcomes. RESULTS:Our results showed that 5hmC levels were globally decreased in posterior fossa ependymoma compared with normal cerebellum tissues (P < 0.001). Group A posterior fossa ependymomas had higher 5hmC levels than group B tumors (P = 0.007). Moreover, 5hmC levels positively correlated with Ki-67 index in posterior fossa ependymoma (r = 0.428, P = 0.003). Multivariate Cox hazards model revealed that patients with high 5hmC levels (>?0.102%) had worse PFS and OS than patients with lower 5hmC levels (<?0.102%) (PFS: HR = 3.014; 95% CI, 1.040-8.738; P = 0.042; OS: HR = 2.788; 95% CI, 0.974-7.982; P = 0.047). CONCLUSIONS:Our findings suggest that loss of 5hmC is an epigenetic hallmark for pediatric posterior fossa ependymoma. 5hmC levels may represent a potential biomarker to predict prognosis in children with posterior fossa ependymoma.
| S-EPMC6988368 | biostudies-literature