Project description:Treatment-resistance of lethal high-grade brain tumors including H3K27M diffuse midline gliomas is thought to arise in part from transcriptional and electrophysiological heterogeneity. These phenotypes are readily studied in isolation using single-cell RNA-seq and whole-cell patch clamping, respectively, but their simultaneous capture is now possible by aspirating a cell's contents into a patch pipet after electrophysiology recordings using a method called 'patch-seq'. Here, we adapt this method to characterize the gene expression programs and functional responses of patient-derived glioma xenografts to neuronal firing at single-cell resolution.
Project description:We used MHC-I immunopeptidomics to study how MTX-241F, a selective EGFR/PI3K inhibitor, alters antigen presentation in diffuse midline glioma (H3K27M) and glioblastoma xenografts. MHC-I–bound peptides from vehicle- and drug-treated tumors were profiled by LC–MS/MS to identify tumor- and treatment-specific peptides, including candidate brain-enriched biomarkers and immunotherapy targets.
Project description:PDGFRA is commonly altered in pediatric high grade gliomas including in histone 3 lysine 27-mutated diffuse midline gliomas (H3K27M DMG), a disease with almost no long-term survivors. We describe effective CNS penetration of a PDGFRA inhibitor with pharmacologically relevant concentrations in brain tumor tissue resulting in dramatic clinical effect and minimal side effects in a cohort of 9 pediatric high grade glioma cases.
Project description:Mutations in the gene encoding histone H3, p.K28M(K27M) and p.G35R/V(G34R/V), are the major driver gene mutations in gliomas. H3 p.K28M(K27M) mutations are frequently found in gliomas arising in midline structures, so called H3K27M-diffuse midline glioma (DMG), while H3 p.G35R/V(G34R/V) mutations are frequently found in pediatric hemispheric gliomas, so called H3G34R/V-diffuse hemispheric glioma (DHG). In contrast, hemispheric glioma with H3 p.K28M(K27M) mutation, known as H3K27M-DHG, is a rare entity and its clinical and molecular characteristics remain to be fully elucidated. We describe a 41-year-old female patient with the right parietal lobe tumor. Following a gross total resection, the pathology showed a high-grade astrocytoma. Sanger sequencing revealed an H3K27M mutation and an IDH1/2-wildtype, leading to the integrated diagnosis of H3K27M-DHG. She underwent chemoradiotherapy with temozolomide and suffered recurrences twice until her death 55 months after the initial diagnosis. The deoxyribonucleic acid methylation profiling classified the tumor as DMG, H3K27-altered, suggesting that it molecularly belonged to the variant of DMG despite a non-median location. Next-generation sequencing on the recurrent tumor detected fibroblast growth factor receptor (FGFR)1 mutation, a favorable prognostic factor in H3K27M-DMG. A relatively prolonged survival of our patient suggests that FGFR1 mutations may also contribute to a better prognosis in H3K27M-DHG.
Project description:H3K27-mutant diffuse hemispheric glioma presenting typical molecular features of diffuse midline glioma: A case report and literature review.