Exercise improves health-related quality of life sleep and fatigue domains in adult high- and low-grade glioma patients

PURPOSE

The impact of exercise on health-related quality of life (HRQOL) in patients with glioma remains unknown. We hypothesized that glioma patients with low exercise tolerance experience more distress in HRQOL sleep and fatigue domains than patients with high tolerance to exercise.

METHODS

Thirty-eight male and female patients with low- or high-grade glioma treated at a single tertiary care institution participated. Patients completed a validated telephone survey to determine their exercise habits before and following diagnosis. An unpaired t-test was run to measure the interaction between exercise tolerances on HRQOL functional and impairment domains.

RESULTS

Those with low pre-morbid physical activity levels had more distress in HRQOL sleep and fatigue domains. The effects were independent of plasma brain-derived neurotrophic factor (BDNF) levels and the degree of exercise did not appear to impact plasma BDNF in adult glioma patients.

CONCLUSIONS

The aim of this study was to examine the significance of exercise habits on perioperative functional outcomes in patients with low-grade or high-grade glioma. We found that glioma patients with low tolerance to exercise had more sleep disturbances and greater fatigue than glioma patients with high tolerance to exercise. Furthermore, exercise tolerance in the adult glioma population does not appear to impact plasma BDNF secretion.

ATRX loss in glioma results in dysregulation of cell-cycle phase transition and ATM inhibitor radio-sensitization

ATRX, a chromatin remodeler protein, is recurrently mutated in H3F3A-mutant pediatric glioblastoma (GBM) and isocitrate dehydrogenase (IDH)-mutant grade 2/3 adult glioma. Previous work has shown that ATRX-deficient GBM cells show enhanced sensitivity to irradiation, but the etiology remains unclear. We find that ATRX binds the regulatory elements of cell-cycle phase transition genes in GBM cells, and there is a marked reduction in Checkpoint Kinase 1 (CHEK1) expression with ATRX loss, leading to the early release of G2/M entry after irradiation. ATRX-deficient cells exhibit enhanced activation of master cell-cycle regulator ATM with irradiation. Addition of the ATM inhibitor AZD0156 doubles median survival in mice intracranially implanted with ATRX-deficient GBM cells, which is not seen in ATRX-wild-type controls. This study demonstrates that ATRX-deficient high-grade gliomas (HGGs) display Chk1-mediated dysregulation of cell-cycle phase transitions, which opens a window for therapies targeting this phenotype.

HGG-18. CLINICAL EFFICACY OF ONC201 IN THALAMIC H3 K27M-MUTANT GLIOMA

ONC201, a bitopic DRD2 antagonist and allosteric ClpP agonist, has shown encouraging efficacy in H3 K27M-mutant glioma. Given that the thalamus has the highest extra-striatal expression of DRD2, we performed an integrated preclinical and clinical analysis of ONC201 in thalamic H3 K27M-mutant glioma. ONC201 was effective in mouse intra-uterine electroporation (IUE)-generated H3 K27M-mutant gliomas, with an in vitro IC₅₀ of 500 nM and 50% prolongation of median survival in vivo (p=0.02, n=14). We analyzed thalamic H3 K27M-mutant glioma patients treated with ONC201 on active clinical trials as of 5/22/19 enrollment (n=19 recurrent and 10 post-radiation, non-recurrent; 5–70 years old). As of 12/18/2019, PFS6 and OS12 are 26.3% and 36.8%, respectively, in the recurrent group. For non-recurrent patients, with median follow up of 21.9 months (8.6–26.6) from diagnosis, median PFS or OS have not been reached. This surpasses historical OS of 13.5 months. Best response by RANO includes 1 CR, 3 PR, 4 SD, 8 PD for recurrent patients and 2 PR, 4 SD, 1 PD for non-recurrent patients (4 on-trial patients experienced regressions that are yet unconfirmed responses). Median duration of response for recurrent patients is 14.0 months (2.0–33.1). Furthermore, H3 K27M cell-free tumor DNA in plasma and CSF correlated with MRI response. In summary, single agent ONC201 administered at recurrence, or adjuvantly following radiation, demonstrates promising clinical efficacy in thalamic H3 K27M-mutant glioma patients who currently have no effective treatments following radiation. Investigations are ongoing to assess whether micro-environmental DRD2 expression explains the early exceptional responses in thalamic H3 K27M-mutant glioma.

DIPG-59. UPREGULATION OF PRENATAL PONTINE ID1 SIGNALING IN DIPG

BACKGROUND

Diffuse intrinsic pontine gliomas (DIPGs) are lethal pediatric brain tumors with no curative therapies. Inhibitor of DNA binding (ID) proteins are key regulators of gene differentiation during embryogenesis. Previous work has shown that H3F3A and ACVR1 mutations increase ID1 expression in cultured astrocytes, but this has not been validated in human DIPG, nor has the regulation and targetability of ID1 been explored in DIPG.

RESULTS

Analysis of post-mortem tissue and multiple human datasets showed ID1 to be elevated in DIPG, and to correlate with reduced survival. In a multi-focal autopsy of a DIPG case, we also found ID1 expression to be heterogeneous and to correlate with tumor invasion. Chromatin immunoprecipitation qPCR (ChIP-qPCR) revealed elevated H3K27ac and low H3K27me3 at ID1 regulatory regions (enhancers/promoters) in DIPG tissue compared to normal brain, regardless of H3 or ACVR1 mutation status. Analysis of publicly-available ISH and ChIP-sequencing data of developing murine brains revealed H3K27ac at ID1 enhancers to be elevated in the prenatal hindbrain compared to prenatal forebrain and midbrain, and all postnatal brain regions. ID1 shRNA-mediated knockdown of primary human H3K27M DIPG cells (DIPG007) significantly reduced invasion and migration. We also treated DIPG007 cells with cannabidiol (CBD) and found reduced viability at clinically relevant dosing (IC50=2.4 uM) with dose-dependent reduction in ID1 protein.

CONCLUSIONS

These findings indicate that a multifactorial (genetic and regionally-based) epigenetic upregulation of ID1 drives DIPG invasiveness and is targetable with CBD. ID1 knockdown and CBD treatment experiments in murine models of DIPG are ongoing.

TAMI-29. MULTIFACTORIAL UPREGULATION OF ID1 DRIVES DIPG INVASIVENESS AND IS THERAPEUTICALLY TARGETABLE

Diffuse intrinsic pontine gliomas (DIPGs) are lethal brain tumors with no effective therapies other than radiation. Inhibitor of DNA binding (ID) proteins, key regulators of lineage commitment during embryogenesis, are implicated in tumorigenesis in multiple human cancers. Prior work showed that recurrent H3F3A and ACVR1 mutations increase ID1 expression in cultured astrocytes. However, this has not been validated in human DIPG. The regulation and targetability of ID1 in DIPG has not been explored either. Exome and transcriptome sequencing analysis of multi-focal DIPG tumors and normal brain tissue from autopsy (n=52) revealed that ID1 expression is significantly elevated in DIPG tissues. Higher ID1 expression correlates with reduced survival in DIPG patients and increased regional invasion in multi-focal autopsy samples. Analyses of developing mouse brain RNA/ChiP-Seq data revealed high ID1 expression and H3K27ac promoter binding in prenatal hind brain compared to all other prenatal and postnatal brain regions. ChIP-qPCR for H3K27ac and H3K27me3 revealed that ID1 gene regulatory regions are epigenetically poised for upregulation in DIPG tissues compared to normal brain, regardless of H3/ACVR1 mutational status. These data support that the developing pons is regionally poised for ID1 activation. Genetic (shRNA) ID1 knockdown in primary human H3.3K27M-DIPG cells (DIPG007) resulted in significantly reduced invasion and migration in vitro. Additionally, DIPG-ID1-KO cells showed improved sensitivity to radiation therapy. Phospho-kinase array analysis of DIPG cells revealed that Akt and WNK1 activity were significantly downregulated upon ID1 knockdown, which was previously shown in lung tumors. Treatment of DIPG007 cells with cannabidiol (CBD) reduced ID1 expression levels and viability/proliferation of DIPG cells in vitro. ID1 knockdown and CBD treatment studies in vivo are ongoing. In summary, our findings indicate that multifactorial (genetic and regional) epigenetic upregulation of ID1 drives DIPG invasiveness and targeting ID1 using CBD may be a potential strategy for the treatment of DIPGs.

CTNI-17. CLINICAL EFFICACY AND PREDICTIVE BIOMARKERS OF ONC201 IN H3 K27M-MUTANT DIFFUSE MIDLINE GLIOMA

Patients with diffuse midline glioma (DMG) harboring H3 K27M mutation rarely survive longer than two years and have no proven therapies following first-line radiation. ONC201, a bitopic DRD2 antagonist and allosteric ClpP agonist, has shown encouraging efficacy in early phase studies in H3 K27M-mutant DMG. In order to define response rates in H3 K27M DMG patients and to clarify the genomic, anatomic and molecular predictors of response, we performed an integrated pre-clinical and clinical analysis of ONC201 treatment. ONC201 was effective in intra-uterine electroporation (IUE)-generated H3 K27M-mutant murine glioma models with excellent CNS penetration and survival benefit. Patients with H3 K27M-mutant DMG treated with ONC201 on active clinical trials (n=50, 27 thalamic, 23 brainstem) showed an overall survival (OS) of 28.1 (range: 5.9–105) months from diagnosis (enrollment by 4/29/19, data cut-off 12/28/19), compared to historical median OS of 12 months. Median OS for non-recurrent patients has not been reached (n=16, median follow-up: 16.8 from diagnosis). For non-recurrent thalamic patients (n=8), median PFS is 20.1 (range: 9.3–27.6) months from diagnosis (median time on drug: 14.5 months). Best response for thalamic patients by RANO: 1 CR, 5 PR, 7 SD, 8 PD, 6 not reported. Decreased H3 K27M cell-free tumor DNA in plasma and CSF at 6 months correlated with long-term response. Baseline tumor gene expression profiling in patients treated with ONC201 (n=14) identified EGFR and the cortical developmental transcription factor FOXG1 as the strongest biomarkers of radiographic response to ONC201. Analysis of 541 ONC201-treated human cancer cell lines from DepMap, provided evidence for an EGFR-dependent ONC201 resistance mechanism. Analysis of 38 glioma cell lines further supports FOXG1 as a glioma-specific predictive biomarker of ONC201 response. The unprecedented survival results and radiographic responses to ONC201 in H3K27M DMG make a compelling case for later phase and combinatorial studies.

CBIO-03. ATRX LOSS IN GLIOMA RESULTS IN EPIGENETIC DYSREGULATION OF CELL CYCLE PHASE TRANSITION

Gliomas are a leading cause of cancer mortality in children and adults, and new targeted therapies are desperately needed. ATRX is a chromatin remodeling protein that is recurrently mutated in H3F3A-mutant pediatric glioblastoma (GBM) and IDH-mutant grade 2/3 adult glioma. We previously showed that loss of ATRX in glioma results in tumor growth and additional tumor mutations. However, the mechanism driving these phenotypes has not been fully established. We found that in ChIP-Seq/ChIP-qPCR of mouse neuronal precursor cells (NPCs) and GBM cells with isogenic ATRX loss, ATRX binds regulatory elements for cell cycle phase transition gene sets, and ATRX loss subsequently results in reduced expression. Furthermore, human GBM cells with ATRX knock-out demonstrate higher rates of cells in S and G2/M phases, with clusters of cells demonstrating reduced expression of cell cycle regulatory gene sets by single-cell sequencing (scSeq) analysis. In human and mouse GBM in vitro models, ATRX-deficient cells exhibit a seven-fold increase in mitotic index at 16 hours after sub-lethal radiation and enhanced activation of the master cell cycle regulator ATM with radiation. Treatment of ATRX-deficient gliomas with ATM inhibitors results in a selective increase in dysfunctional cell cycling and increased radio-sensitization in ATRX-deficient glioma cells. Using an ATM-luciferase reporter in orthotopically-implanted human GBM cells, both AZD0156 and AZD1390 demonstrate in vivo pathway inhibition. Mice intra-cranially implanted with ATRX-deficient GBM cells demonstrate a doubling of median survival compared to radiated controls (p=0.0018) when treated with AZD0156 combined with radiation; this is not seen in ATRX-sufficient models. This study demonstrates that ATRX-deficient high-grade gliomas display epigenetic dysregulation of cell cycle phase transitions, which opens a new window for therapies targeting this unique phenotype.

Everolimus improves the efficacy of dasatinib in PDGFRα-driven glioma

Pediatric and adult high-grade gliomas (HGGs) frequently harbor PDGFRA alterations. We hypothesized that cotreatment with everolimus may improve the efficacy of dasatinib in PDGFRα-driven glioma through combinatorial synergism and increased tumor accumulation of dasatinib. We performed dose-response, synergism, P-glycoprotein inhibition, and pharmacokinetic studies in in vitro and in vivo human and mouse models of HGG. Six patients with recurrent PDGFRα-driven glioma were treated with dasatinib and everolimus. We found that dasatinib effectively inhibited the proliferation of mouse and human primary HGG cells with a variety of PDGFRA alterations. Dasatinib exhibited synergy with everolimus in the treatment of HGG cells at low nanomolar concentrations of both agents, with a reduction in mTOR signaling that persisted after dasatinib treatment alone. Prolonged exposure to everolimus significantly improved the CNS retention of dasatinib and extended the survival of PPK tumor-bearing mice (mutant TP53, mutant PDGFRA, H3K27M). Six pediatric patients with glioma tolerated this combination without significant adverse events, and 4 patients with recurrent disease (n = 4) had a median overall survival of 8.5 months. Our results show that the efficacy of dasatinib treatment of PDGFRα-driven HGG was enhanced with everolimus and suggest a promising route for improving targeted therapy for this patient population.

EXTH-47. THERAPEUTIC REVERSAL OF PRENATAL PONTINE ID1 SIGNALING IN DIPG

Diffuse intrinsic pontine gliomas (DIPGs) are lethal brain tumors with no effective therapies other than radiation. Inhibitor of DNA binding (ID) proteins are key regulators of tissue and lineage-specific gene differentiation during embryogenesis. Previous work has shown that H3F3A and ACVR1 mutations increase ID1 expression in cultured astrocytes, but this has not been validated in human DIPG, nor has the regulation and targetability of ID1 been explored in DIPG. Analysis of multi-focal post-mortem tumor and normal brain tissue (n=52) as well as multiple human datasets revealed ID1 to be elevated in DIPG. Elevated ID1 was found to correlate with reduced survival in DIPG. In a multi-focal autopsy DIPG case, we found ID1 expression to be heterogeneous and to correlate with tumor invasion. Chromatin immunoprecipitation-qPCR (ChIP-qPCR) was used to quantify H3K27ac and H3K27me3 at ID1 gene regulatory regions (promoters/enhancers) in multi-focal post-mortem tissue. The ID1 loci was found to be epigenetically poised for up-regulation (elevated H3K27ac and low H3K27me3) in DIPG tissue, regardless of H3 or ACVR1 mutation status, compared to normal brain. Analysis of publically-available ISH and ChIP-sequencing data revealed elevated ID1 expression and ID1-enhancer H3K27ac in prenatal mouse hindbrain compared to prenatal forebrain, prenatal midbrain, and all postnatal brain regions. ID1 shRNA-mediated knockdown of primary human H3K27M DIPG cells (DIPG007) resulted in significantly reduced invasion and migration. As cannabidiol (CBD) has successfully been used to therapeutically target ID1 in pre-clinical models of adult human cancers, we treated DIPG007 cells with CBD and found reduced viability at clinically relevant dosing (IC50=2.4 uM) with dose-dependent reduction in ID1 protein. ID1 knockdown and CBD treatment studies in murine models of DIPG are ongoing. These findings indicate that a multifactorial (genetic and regionally-based) epigenetic upregulation of ID1 drives DIPG invasiveness and is targetable with CBD.

PDCT-12. CLINICAL EFFICACY OF ONC201 IN THALAMIC H3 K27M-MUTANT GLIOMA

ONC201, the first bitopic DRD2 antagonist for clinical oncology, has shown efficacy in H3 K27M-mutant glioma. We performed an integrated preclinical and clinical analysis of ONC201 in thalamic H3 K27M-mutant glioma. ONC201 was effective in mouse intra-uterine electroporation (IUE)-generated H3 K27M-mutant gliomas, with an in vitro IC50 of 500 nM and 50% prolongation of median survival in vivo (p=0.02, n=14). Elevated DRD2 expression was found in the thalamus of non-malignant brain tissue, leading to the hypothesis that thalamic tumors may be a particularly ONC201-sensitive sub-group. We analyzed thalamic H3 K27M-mutant glioma patients treated with ONC201 as of the 05/22/2019 cutoff date, which included patients who had recurrent disease prior to initiating ONC201 (n=20; 15–73 years old) and post-radiation non-recurrent patients (n=11; 5–19 years old). As of 5/22/2019, 10 of 20 recurrent patients and 9 of 11 non-recurrent patients remain on-treatment. Median PFS has not been reached for either cohort: median follow-up of 2.2 months (range: 0.6–37.9) for recurrent patients and 10.6 months (range: 4.3–20.5) from diagnosis for non-recurrent patients. Best response so far by RANO includes 1 CR, 2 PR, 7 SD, 9 PD, 1 NE for recurrent patients and 1 PR, 7 SD, 3 PD for non-recurrent patients. Additionally, 3 recurrent (-66%, -47%, -34%) and 2 non-recurrent (-40%, -10%) patients experienced regressions but are not yet confirmed PRs. For recurrent patients, median onset of response is 3.5 months (range: 2.2–3.8) and median duration of response has not been reached with a median follow-up of 12.5 months (range: 8.1–32.8). Preliminary analyses demonstrated a strong correlation of cell-free tumor DNA in plasma and CSF with MRI response. In summary, ONC201 demonstrates promising clinical efficacy in thalamic H3 K27M-mutant glioma patients, regardless of age. Micro-environmental DRD2 expression may enhance the overall ONC201 response and extend its therapeutic utility beyond H3 K27M-mutant glioma.

BDNF, COMT, and DRD2 polymorphisms and ability to return to work in adult patients with low- and high-grade glioma

BACKGROUND

Cognitive and language dysfunction is common among patients with glioma and has a significant impact on survival and health-related quality of life (HRQOL). Little is known about the factors that make individual patients more or less susceptible to the cognitive sequelae of the disease. A better understanding of the individual and population characteristics related to cognitive function in glioma patients is required to appropriately stratify patients, prognosticate, and develop more efficacious treatment regimens. There is evidence that allelic variation among genes involved in neurotransmission and synaptic plasticity are related to neurocognitive performance in states of health and neurologic disease.

METHODS

We studied the association of single-nucleotide polymorphism variations in brain-derived neurotrophic factor (BDNF, rs6265), dopamine receptor 2 (DRD2, rs1076560), and catechol-O-methyltransferase (COMT, rs4680) with neurocognitive function and ability to return to work in glioma patients at diagnosis and at 3 months. We developed a functional score based on the number of high-performance alleles that correlates with the capacity for patients to return to work.

RESULTS

Patients with higher-performing alleles have better scores on neurocognitive testing with the Repeatable Battery for the Assessment of Neuropsychological Status and Stroop test, but not the Trail Making Test.

CONCLUSIONS

A better understanding of the genetic contributors to neurocognitive performance in glioma patients and capacity for functional recovery is necessary to develop improved treatment strategies based on patient-specific factors.

Molecular profiling and targeted therapy in pediatric gliomas: review and consensus recommendations

As the field of neuro-oncology makes headway in uncovering the key oncogenic drivers in pediatric glioma, the role of precision diagnostics and therapies continues to rapidly evolve with important implications for the standard of care for clinical management of these patients. Four studies at major academic centers were published in the last year outlining the clinically integrated molecular profiling and targeting of pediatric brain tumors; all 4 demonstrated the feasibility and utility of incorporating sequencing into the care of children with brain tumors, in particular for children and young adults with glioma. Based on synthesis of the data from these studies and others, we provide consensus recommendations for the integration of precision diagnostics and therapeutics into the practice of pediatric neuro-oncology. Our primary consensus recommendation is that next-generation sequencing should be routinely included in the workup of most pediatric gliomas.

The effect of everolimus on CNS penetration and efficacy of dasatinib in the treatment of PDGFRA-driven glioma

e13508

Background: Pediatric and adult high-grade glioma (HGG) frequently harbor PDGFRA alterations. The CNS penetration of PDGFRA inhibitors, such as dasatinib, is limited by the tumor-efflux protein P-glycoprotein (P-gp). We hypothesized that co-treatment with everolimus, which has been shown to block P-gp, will increase CNS penetration and efficacy of dasatinib in in vitro and in vivo models as well as in human PDGFRA-driven glioma. Methods: Tumors were generated in mice using an intra-uterine electroporation (IUE) model [introduction of TP53, PDGFRA and H3K27M mutations in pre-natal cortex]. Dose response, synergism studies, P-GP inhibition and pharmacodynamics/pharmacokinetic studies were then performed on in vitro and in vivo models employing this IUE system. A phase 2 trial employing dasatinib and everolimus was established for children with HGG and diffuse intrinsic pontine glioma (DIPG) that contain PDGFRA alterations (NCT03352427). Paired CSF/plasma samples (before and after addition of everolimus) were collected from enrolled patients. Results: Dasatinib effectively treated mouse HGG cells with an IC50 of 100 nM. Dose-dependent reduction in PDGFRA and pPDGFRA was found. P-gp inhibitor assay confirmed that everolimus strongly blocks P-gp activity at 1 uM (p = 0.0028 vs untreated). Mice treated with dasatinib and everolimus had extended survival as compared to control. Two-hour exposure to everolimus resulted in sub-IC50 dasatinib concentration in cortex (23 nM) and tumor (65 nM). 24-hour exposure to everolimus resulted in greater cortex (235 nM) and tumor (509 nM) concentrations. Two trial patients, recurrent HGG ( PDGFRA-amplified) and recurrent DIPG ( PDGFRA D842V) respectively, survived 6 months and 9 months (ongoing) after progression, which compares very favorably to historical controls. A paired CSF sample from the PDGFRA-amplified patient showed a 50% increase in CSF dasatinib level after addition of everolimus. Conclusions: Dasatinib treatment of PDGFRA-driven HGG is improved with everolimus blockade of P-gp and represents a novel route for improving CNS penetration and efficacy of therapies for HGG. Clinical trial information: NCT03352427.

Health Related Quality of Life in Adult Low and High-Grade Glioma Patients Using the National Institutes of Health Patient Reported Outcomes Measurement Information System (PROMIS) and Neuro-QOL Assessments

Health related quality of life (HRQOL) measures have become increasingly important in the management of glioma patients in both research and clinical practice settings. Functional impairment is common in low-grade and high-grade glioma patients as the disease has both oncological and neurological manifestations. Natural disease history as well as medical or surgical treatment can negatively influence HRQOL. There are no universal standards for HRQOL assessment in glioma patients. In this study, we examine patient perspectives on functional outcome domains and report the prevalence of impairments rates using the National Institutes of Health (NIH) Patient Reported Outcomes Measurement Information System (PROMIS) and Neuro-QOL item banks as measures of HRQOL. Retrospective analysis of a prospectively collected dataset involving 79 glioma patients reveals that quality of life concerns are the most important consideration behind making decisions about treatment in 80.7% of patients. The prevalence of functional impairment by PROMIS and NEURO-QOL assessment is high, ranging from 28.6% in the physical function domain to 43.9% in the cognitive function domain. Pain and anxiety related to physical decline is higher in LGG patients compared to HGG patients. Aphasia severity also impacts HRQOL. The results of this study suggest that the PROMIS and NEURO-QOL assessments may be important HRQOL metrics for future use in larger clinical research and clinical trial settings.