Browsing by Subject "Brain Stem Neoplasms"

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Open Access
A high-throughput in vitro drug screen in a genetically engineered mouse model of diffuse intrinsic pontine glioma identifies BMS-754807 as a promising therapeutic agent.
(PLoS One, 2015) Halvorson, Kyle G; Barton, Kelly L; Schroeder, Kristin; Misuraca, Katherine L; Hoeman, Christine; Chung, Alex; Crabtree, Donna M; Cordero, Francisco J; Singh, Raj; Spasojevic, Ivan; Berlow, Noah; Pal, Ranadip; Becher, Oren J
Diffuse intrinsic pontine gliomas (DIPGs) represent a particularly lethal type of pediatric brain cancer with no effective therapeutic options. Our laboratory has previously reported the development of genetically engineered DIPG mouse models using the RCAS/tv-a system, including a model driven by PDGF-B, H3.3K27M, and p53 loss. These models can serve as a platform in which to test novel therapeutics prior to the initiation of human clinical trials. In this study, an in vitro high-throughput drug screen as part of the DIPG preclinical consortium using cell-lines derived from our DIPG models identified BMS-754807 as a drug of interest in DIPG. BMS-754807 is a potent and reversible small molecule multi-kinase inhibitor with many targets including IGF-1R, IR, MET, TRKA, TRKB, AURKA, AURKB. In vitro evaluation showed significant cytotoxic effects with an IC50 of 0.13 μM, significant inhibition of proliferation at a concentration of 1.5 μM, as well as inhibition of AKT activation. Interestingly, IGF-1R signaling was absent in serum-free cultures from the PDGF-B; H3.3K27M; p53 deficient model suggesting that the antitumor activity of BMS-754807 in this model is independent of IGF-1R. In vivo, systemic administration of BMS-754807 to DIPG-bearing mice did not prolong survival. Pharmacokinetic analysis demonstrated that tumor tissue drug concentrations of BMS-754807 were well below the identified IC50, suggesting that inadequate drug delivery may limit in vivo efficacy. In summary, an unbiased in vitro drug screen identified BMS-754807 as a potential therapeutic agent in DIPG, but BMS-754807 treatment in vivo by systemic delivery did not significantly prolong survival of DIPG-bearing mice.
Open Access
A Novel Mouse Model of Diffuse Intrinsic Pontine Glioma Initiated in Pax3-Expressing Cells.
(Neoplasia, 2016-01) Misuraca, Katherine L; Hu, Guo; Barton, Kelly L; Chung, Alexander; Becher, Oren J
Diffuse intrinsic pontine glioma (DIPG) is a rare and incurable brain tumor that arises predominately in children and involves the pons, a structure that along with the midbrain and medulla makes up the brainstem. We have previously developed genetically engineered mouse models of brainstem glioma using the RCAS/Tv-a system by targeting PDGF-B overexpression, p53 loss, and H3.3K27M mutation to Nestin-expressing brainstem progenitor cells of the neonatal mouse. Here we describe a novel mouse model targeting these same genetic alterations to Pax3-expressing cells, which in the neonatal mouse pons consist of a Pax3+/Nestin+/Sox2+ population lining the fourth ventricle and a Pax3+/NeuN+ parenchymal population. Injection of RCAS-PDGF-B into the brainstem of Pax3-Tv-a mice at postnatal day 3 results in 40% of mice developing asymptomatic low-grade glioma. A mixture of low- and high-grade glioma results from injection of Pax3-Tv-a;p53(fl/fl) mice with RCAS-PDGF-B and RCAS-Cre, with or without RCAS-H3.3K27M. These tumors are Ki67+, Nestin+, Olig2+, and largely GFAP- and can arise anywhere within the brainstem, including the classic DIPG location of the ventral pons. Expression of the H3.3K27M mutation reduces overall H3K27me3 as compared with tumors without the mutation, similar to what has been previously shown in human and mouse tumors. Thus, we have generated a novel genetically engineered mouse model of DIPG, which faithfully recapitulates the human disease and represents a novel platform with which to study the biology and treatment of this deadly disease.
Open Access
GD2-CAR T cell therapy for H3K27M-mutated diffuse midline gliomas.
(Nature, 2022-03) Majzner, Robbie G; Ramakrishna, Sneha; Yeom, Kristen W; Patel, Shabnum; Chinnasamy, Harshini; Schultz, Liora M; Richards, Rebecca M; Jiang, Li; Barsan, Valentin; Mancusi, Rebecca; Geraghty, Anna C; Good, Zinaida; Mochizuki, Aaron Y; Gillespie, Shawn M; Toland, Angus Martin Shaw; Mahdi, Jasia; Reschke, Agnes; Nie, Esther H; Chau, Isabelle J; Rotiroti, Maria Caterina; Mount, Christopher W; Baggott, Christina; Mavroukakis, Sharon; Egeler, Emily; Moon, Jennifer; Erickson, Courtney; Green, Sean; Kunicki, Michael; Fujimoto, Michelle; Ehlinger, Zach; Reynolds, Warren; Kurra, Sreevidya; Warren, Katherine E; Prabhu, Snehit; Vogel, Hannes; Rasmussen, Lindsey; Cornell, Timothy T; Partap, Sonia; Fisher, Paul G; Campen, Cynthia J; Filbin, Mariella G; Grant, Gerald; Sahaf, Bita; Davis, Kara L; Feldman, Steven A; Mackall, Crystal L; Monje, Michelle
Diffuse intrinsic pontine glioma (DIPG) and other H3K27M-mutated diffuse midline gliomas (DMGs) are universally lethal paediatric tumours of the central nervous system¹. We have previously shown that the disialoganglioside GD2 is highly expressed on H3K27M-mutated glioma cells and have demonstrated promising preclinical efficacy of GD2-directed chimeric antigen receptor (CAR) T cells², providing the rationale for a first-in-human phase I clinical trial (NCT04196413). Because CAR T cell-induced brainstem inflammation can result in obstructive hydrocephalus, increased intracranial pressure and dangerous tissue shifts, neurocritical care precautions were incorporated. Here we present the clinical experience from the first four patients with H3K27M-mutated DIPG or spinal cord DMG treated with GD2-CAR T cells at dose level 1 (1 × 10⁶ GD2-CAR T cells per kg administered intravenously). Patients who exhibited clinical benefit were eligible for subsequent GD2-CAR T cell infusions administered intracerebroventricularly³. Toxicity was largely related to the location of the tumour and was reversible with intensive supportive care. On-target, off-tumour toxicity was not observed. Three of four patients exhibited clinical and radiographic improvement. Pro-inflammatory cytokine levels were increased in the plasma and cerebrospinal fluid. Transcriptomic analyses of 65,598 single cells from CAR T cell products and cerebrospinal fluid elucidate heterogeneity in response between participants and administration routes. These early results underscore the promise of this therapeutic approach for patients with H3K27M-mutated DIPG or spinal cord DMG.
Open Access
Genomic analysis of diffuse intrinsic pontine gliomas identifies three molecular subgroups and recurrent activating ACVR1 mutations.
(Nat Genet, 2014-05) Buczkowicz, Pawel; Hoeman, Christine; Rakopoulos, Patricia; Pajovic, Sanja; Letourneau, Louis; Dzamba, Misko; Morrison, Andrew; Lewis, Peter; Bouffet, Eric; Bartels, Ute; Zuccaro, Jennifer; Agnihotri, Sameer; Ryall, Scott; Barszczyk, Mark; Chornenkyy, Yevgen; Bourgey, Mathieu; Bourque, Guillaume; Montpetit, Alexandre; Cordero, Francisco; Castelo-Branco, Pedro; Mangerel, Joshua; Tabori, Uri; Ho, King Ching; Huang, Annie; Taylor, Kathryn R; Mackay, Alan; Bendel, Anne E; Nazarian, Javad; Fangusaro, Jason R; Karajannis, Matthias A; Zagzag, David; Foreman, Nicholas K; Donson, Andrew; Hegert, Julia V; Smith, Amy; Chan, Jennifer; Lafay-Cousin, Lucy; Dunn, Sandra; Hukin, Juliette; Dunham, Chris; Scheinemann, Katrin; Michaud, Jean; Zelcer, Shayna; Ramsay, David; Cain, Jason; Brennan, Cameron; Souweidane, Mark M; Jones, Chris; Allis, C David; Brudno, Michael; Becher, Oren; Hawkins, Cynthia
Diffuse intrinsic pontine glioma (DIPG) is a fatal brain cancer that arises in the brainstem of children, with no effective treatment and near 100% fatality. The failure of most therapies can be attributed to the delicate location of these tumors and to the selection of therapies on the basis of assumptions that DIPGs are molecularly similar to adult disease. Recent studies have unraveled the unique genetic makeup of this brain cancer, with nearly 80% found to harbor a p.Lys27Met histone H3.3 or p.Lys27Met histone H3.1 alteration. However, DIPGs are still thought of as one disease, with limited understanding of the genetic drivers of these tumors. To understand what drives DIPGs, we integrated whole-genome sequencing with methylation, expression and copy number profiling, discovering that DIPGs comprise three molecularly distinct subgroups (H3-K27M, silent and MYCN) and uncovering a new recurrent activating mutation affecting the activin receptor gene ACVR1 in 20% of DIPGs. Mutations in ACVR1 were constitutively activating, leading to SMAD phosphorylation and increased expression of the downstream activin signaling targets ID1 and ID2. Our results highlight distinct molecular subgroups and novel therapeutic targets for this incurable pediatric cancer.
Open Access
Pax3 expression enhances PDGF-B-induced brainstem gliomagenesis and characterizes a subset of brainstem glioma.
(Acta Neuropathol Commun, 2014-10-21) Misuraca, Katherine L; Barton, Kelly L; Chung, Alexander; Diaz, Alexander K; Conway, Simon J; Corcoran, David L; Baker, Suzanne J; Becher, Oren J
High-grade Brainstem Glioma (BSG), also known as Diffuse Intrinsic Pontine Glioma (DIPG), is an incurable pediatric brain cancer. Increasing evidence supports the existence of regional differences in gliomagenesis such that BSG is considered a distinct disease from glioma of the cerebral cortex (CG). In an effort to elucidate unique characteristics of BSG, we conducted expression analysis of mouse PDGF-B-driven BSG and CG initiated in Nestin progenitor cells and identified a short list of expression changes specific to the brainstem gliomagenesis process, including abnormal upregulation of paired box 3 (Pax3). In the neonatal mouse brain, Pax3 expression marks a subset of brainstem progenitor cells, while it is absent from the cerebral cortex, mirroring its regional expression in glioma. Ectopic expression of Pax3 in normal brainstem progenitors in vitro shows that Pax3 inhibits apoptosis. Pax3-induced inhibition of apoptosis is p53-dependent, however, and in the absence of p53, Pax3 promotes proliferation of brainstem progenitors. In vivo, Pax3 enhances PDGF-B-driven gliomagenesis by shortening tumor latency and increasing tumor penetrance and grade, in a region-specific manner, while loss of Pax3 function extends survival of PDGF-B-driven;p53-deficient BSG-bearing mice by 33%. Importantly, Pax3 is regionally expressed in human glioma as well, with high PAX3 mRNA characterizing 40% of human BSG, revealing a subset of tumors that significantly associates with PDGFRA alterations, amplifications of cell cycle regulatory genes, and is exclusive of ACVR1 mutations. Collectively, these data suggest that regional Pax3 expression not only marks a novel subset of BSG but also contributes to PDGF-B-induced brainstem gliomagenesis.