Integrated Molecular Meta-Analysis of 1,000 Pediatric High-Grade and Diffuse Intrinsic Pontine Glioma.

We collated data from 157 unpublished cases of pediatric high-grade glioma and diffuse intrinsic pontine glioma and 20 publicly available datasets in an integrated analysis of >1,000 cases. We identified co-segregating mutations in histone-mutant subgroups including loss of FBXW7 in H3.3G34R/V, TOP3A rearrangements in H3.3K27M, and BCOR mutations in H3.1K27M. Histone wild-type subgroups are refined by the presence of key oncogenic events or methylation profiles more closely resembling lower-grade tumors. Genomic aberrations increase with age, highlighting the infant population as biologically and clinically distinct. Uncommon pathway dysregulation is seen in small subsets of tumors, further defining the molecular diversity of the disease, opening up avenues for biological study and providing a basis for functionally defined future treatment stratification

Surgical and oncological score to estimate the survival benefit of resection and chemoradiotherapy in elderly (≥70 years) glioblastoma patients: A preliminary analysis.

BACKGROUND: Elderly patients with glioblastoma are perceived to face a poor prognosis with perceptions surrounding older age and a relative lack of randomized data contributing. This study evaluated survival prognosticators in elderly glioblastoma patients to more accurately guide their treatment. METHODS: The records of 169 elderly (≥70 years) patients with a new diagnosis of glioblastoma who had undergone neurosurgical intervention were retrospectively examined for patient sex, age, performance status, comorbidities, MGMT promoter methylation, surgical intervention, and chemoradiation regime. The adjusted survival impact of these factors was determined using Cox proportional hazards model and used to devise a two-stage scoring system to estimate patient survival at the stage of surgical (Elderly Glioblastoma Surgical Score, EGSS) and oncological management (Elderly Glioblastoma Oncological Score, EGOS). RESULTS: The median overall survival (mOS) of the cohort was 28.8 weeks. Gross-total and subtotal resection were associated with improved survival compared to biopsy alone (respective mOS 65.3 and 28.1 vs 15.7 weeks, P < .001). Hypofractionated radiotherapy (40Gy in 15 fractions) with Temozolomide was noninferior to the Stupp protocol, P = .72. Exploratory subgroup analysis revealed a significant benefit of Temozolomide-based approaches in MGMT-methylated patients as well as a trend towards improved survival in MGMT-unmethylated patients. Our EGSS and EGOS scores successfully estimated survival in this retrospective cohort with 65% and 73% accuracy. CONCLUSIONS: Where appropriate and safe, elderly glioblastoma patients may benefit from surgical resection and combined chemoradiotherapy with Temozolomide. The proposed EGSS and EGOS scores take into account important prognostic factors to help guide which patients should receive such treatment

Histone H3.3 Mutations Drive Pediatric Glioblastoma through Upregulation of MYCN

UnlabelledChildren and young adults with glioblastoma (GBM) have a median survival rate of only 12 to 15 months, and these GBMs are clinically and biologically distinct from histologically similar cancers in older adults. They are defined by highly specific mutations in the gene encoding the histone H3.3 variant H3F3A , occurring either at or close to key residues marked by methylation for regulation of transcription—K27 and G34. Here, we show that the cerebral hemisphere-specific G34 mutation drives a distinct expression signature through differential genomic binding of the K36 trimethylation mark (H3K36me3). The transcriptional program induced recapitulates that of the developing forebrain, and involves numerous markers of stem-cell maintenance, cell-fate decisions, and self-renewal.Critically, H3F3A G34 mutations cause profound upregulation of MYCN , a potent oncogene that is causative of GBMs when expressed in the correct developmental context. This driving aberration is selectively targetable in this patient population through inhibiting kinases responsible for stabilization of the protein.SignificanceWe provide the mechanistic explanation for how the fi rst histone gene mutation inhuman disease biology acts to deliver MYCN, a potent tumorigenic initiator, into a stem-cell compartment of the developing forebrain, selectively giving rise to incurable cerebral hemispheric GBM. Using synthetic lethal approaches to these mutant tumor cells provides a rational way to develop novel and highly selective treatment strategie