Project description:Diagnosis of glioma into the hierarchy of human brain development would greatly facilitate mechanistic studies and clinical services in combating glioma. By analysing the multi-dimension big data of glioma genome and clinical manifestations, we have recently developed an EM/PM classification scheme anchored in the brain development and glioma pathogenesis (Sun et al., PNAS 111:3538-3543, 2014). To translate the EM/PM classification into a clinical diagnostic tool, we here designed and validated a TaqMan low-density RT-PCR array (TLDA) and a support vector machine (SVM) based prediction model that enables individual diagnosis of gliomas into the EM/PM subtype with high accuracy and precision. Results of 153 individually diagnosed adult diffuse gliomas of WHO grades II-IV derived from Chinese or Swedish patients confirmed our previous data base investigations: EM and PM gliomas show distinct prognosis, occur at different ages, and harbor mutually exclusive patterns of genomic alterations detected by Sanger sequencing and shallow-coverage whole genome sequencing (WGS). Further, we show that shallow-coverage WGS enabled a systematic identification of clonal and subclonal copy number variations (CNV) in glioma genomes, and the extent and the pattern of CNV can serve as an objective marker of tumor progression in the PM gliomas harboring IDH mutations.
Project description:Diagnosis of glioma into the hierarchy of human brain development would greatly facilitate mechanistic studies and clinical services in combating glioma. By analysing the multi-dimension big data of glioma genome and clinical manifestations, we have recently developed an EM/PM classification scheme anchored in the brain development and glioma pathogenesis (Sun et al., PNAS 111:3538-3543, 2014). To translate the EM/PM classification into a clinical diagnostic tool, we here designed and validated a TaqMan low-density RT-PCR array (TLDA) and a support vector machine (SVM) based prediction model that enables individual diagnosis of gliomas into the EM/PM subtype with high accuracy and precision. Results of 153 individually diagnosed adult diffuse gliomas of WHO grades II-IV derived from Chinese or Swedish patients confirmed our previous data base investigations: EM and PM gliomas show distinct prognosis, occur at different ages, and harbor mutually exclusive patterns of genomic alterations detected by Sanger sequencing and shallow-coverage whole genome sequencing (WGS). Further, we show that shallow-coverage WGS enabled a systematic identification of clonal and subclonal copy number variations (CNV) in glioma genomes, and the extent and the pattern of CNV can serve as an objective marker of tumor progression in the PM gliomas harboring IDH mutations.
Project description:Individual Assignment of Adult Diffuse Gliomas into the EM/PM Molecular Subtypes Using a TaqMan Low-Density Array [Human Clariom D array]
Project description:Individual Assignment of Adult Diffuse Gliomas into the EM/PM Molecular Subtypes Using a TaqMan Low-Density Array [Taqman Low Density Array]
Project description:This phase I trial studies the side effects and best dose of pembrolizumab and to see how well it works in treating younger patients with high-grade gliomas (brain tumors that are generally expected to be fast growing and aggressive), diffuse intrinsic pontine gliomas (brain stem tumors), brain tumors with a high number of genetic mutations, ependymoma or medulloblastoma that have come back (recurrent), progressed, or have not responded to previous treatment (refractory). Immunotherapy with monoclonal antibodies, such as pembrolizumab, may induce changes in the body’s immune system, and may interfere with the ability of tumor cells to grow and spread.
Project description:Purpose: More than 90% of children with diffuse intrinsic pontine glioma (DIPG) die within 2 years of diagnosis. There is a dire need to identify therapeutic targets, however lack of patient material for research has limited progress. We evaluated a large cohort of diffuse intrinsic pontine gliomas (DIPGs) to identify recurrent genomic abnormalities and gene expression signatures underlying DIPG. Patients and Methods: We used single nucleotide polymorphism arrays to evaluate genomic copy number imbalances in 43 DIPGs from 40 patients and in 8 low-grade exophytic brainstem gliomas. Gene expression arrays were used to evaluate expression signatures from 27 DIPGs, 6 low-grade exophytic brainstem gliomas and 66 low-grade gliomas arising outside the brainstem. Results: Frequencies of specific large-scale and focal imbalances varied significantly between DIPGs and pediatric glioblastomas outside the brainstem. Focal amplifications of genes within the receptor tyrosine kinase-Ras-PI3-kinase signaling pathway were found in 47% of DIPG, with PDGFRA and MET showing the highest frequency. 30% of DIPG contained focal amplifications of cell-cycle regulatory genes controlling RB phosphorylation, and 21% had concurrent amplification of genes from both pathways. Some tumors showed heterogeneity in amplification patterns. DIPGs showed distinct gene expression signatures relating to developmental processes compared to pediatric glioblastomas arising outside the brainstem, while expression signatures of low-grade exophytic brainstem gliomas were similar to low-grade gliomas outside the brainstem. Copy number analaysis: 43 DIPG samples, 8 Low Grade Gliomas using SNP6.0. Available matched normals are also profiled with SNP6.0. Expression analysis: 29 DIPG samples, 6 Low grade samples Please contact Suzanne Baker at Suzanne.Baker@stjude.org for CEL files and genotype calls.
Project description:We have used Illumina Infinium HumanMethylation450 BeadChip array profiling to profile paediatric high grade gliomas and diffuse intrinsic pontine gliomas. The 450K methylation array is being used to separate brain tumour samples on the basis of their methylation profiles which represent the cell of origin the time and place in which tumours arise. Methylation arrays provide data for an integrated molecular diagnosis of brain tumours and define specific molecular subgroups and subtypes of high grade gliomas carrying distinct driver mutations and patterns of somatic alterations. These data form part of an integrated meta-analysis of high grade gliomas in children combining DNA copy number, methylation and high throughput sequencing datasets.
Project description:Genome-wide DNA methylation profiling of 10 pediatric bithalamic diffuse gliomas. The Illumina Infiunium 450k Human DNA Methylation Beadchip (n=4) or the Infinium EPIC 850k Human DNA Methylation Beadchip (n=6) was used to obtain DNA methylation profiles across approximately 450,000 or 850,000 CpG sites of genomic DNA extracted from formalin-fixed, paraffin-embedded tumor tissue of 10 pediatric bithalamic diffuse gliomas.
Project description:Purpose: More than 90% of children with diffuse intrinsic pontine glioma (DIPG) die within 2 years of diagnosis. There is a dire need to identify therapeutic targets, however lack of patient material for research has limited progress. We evaluated a large cohort of diffuse intrinsic pontine gliomas (DIPGs) to identify recurrent genomic abnormalities and gene expression signatures underlying DIPG. Patients and Methods: We used single nucleotide polymorphism arrays to evaluate genomic copy number imbalances in 43 DIPGs from 40 patients and in 8 low-grade exophytic brainstem gliomas. Gene expression arrays were used to evaluate expression signatures from 27 DIPGs, 6 low-grade exophytic brainstem gliomas and 66 low-grade gliomas arising outside the brainstem. Results: Frequencies of specific large-scale and focal imbalances varied significantly between DIPGs and pediatric glioblastomas outside the brainstem. Focal amplifications of genes within the receptor tyrosine kinase-Ras-PI3-kinase signaling pathway were found in 47% of DIPG, with PDGFRA and MET showing the highest frequency. 30% of DIPG contained focal amplifications of cell-cycle regulatory genes controlling RB phosphorylation, and 21% had concurrent amplification of genes from both pathways. Some tumors showed heterogeneity in amplification patterns. DIPGs showed distinct gene expression signatures relating to developmental processes compared to pediatric glioblastomas arising outside the brainstem, while expression signatures of low-grade exophytic brainstem gliomas were similar to low-grade gliomas outside the brainstem.