bluuebunny/crossref_metadata_2025_split huggingface dataset:
TMIC-28. LONG NON-CODING RNA EXPRESSION DIFFERS BETWEEN GLIOBLASTOMA PATIENT IMMUNE CELLS AND HEALTHY VOLUNTEERS
Authors: Nwankwo Anthony , Sanchez Victoria , Lynes John , Wang Xiang , Dominah Gifty , Obungu Arnold , Edwards Nancy , Sarpong Kwadwo , Ariyo Oluwatobi , Johnson Kory , K Nduom Edjah 
Published: November 2019

Abstract
To improve glioblastoma treatment, improved characterization of the tumor’s immune microenvironment is critical. Aberrant long non-coding RNA (LncRNA) expression has been implicated in the pathogenesis of many cancers, including glioblastoma. Other studies have discovered long non-coding RNAs which regulate immunity. However, lncRNA expression has not been systematically investigated glioblastoma patient immune cells. We aimed to investigate the differential expression of LncRNA and mRNs in the T lymphocytes and monocytes of glioblastoma patients when compared to healthy controls in an unbiased fashion. CD3 and CD14 cells were sorted from PBMC samples from 3 newly diagnosed glioblastoma patients and 3 normal donors, and RNA was extracted from them. These RNA samples were run on the Arraystar Human LncRNA microarray. We found 309 LncRNAs differentially expressed in glioblastoma patient T cells, and 316 in patient monocytes (fold change >2 or £0.5, P£0.05). A preliminary review of this data has revealed upregulation of lncRNAs that have previously been reported to play a role in tumorigenesis, such as MIF12-AS1, VIM-AS1, and WEE2-AS1. Additionally, lncRNAs such as CCDC26 and Hoxa10 that have been implicated in immune cell differentiation and hyperactivity also show differential expression between the two groups. We also found differential expression of 203 mRNA in T cells and 467 in monocytes (fold change ³2 or £0.5, P£0.05). An analysis based on the Kyoto Encyclopedia of Genes and Genomes identified 42 biological pathways that have enrichment of these differentially expressed mRNAs (P£0.05), including the RIG-I-like receptor pathway and toll-like receptor pathway, both implicated in innate immunity in T-cells. This array data will form the template for future single-cell RNA sequencing of tumor-infiltrating immune cells; peripheral immune cells from glioblastoma patients; and immune cells from non-tumorous brain (epilepsy tissue) and blood samples to investigate these differences in greater detail.
TMIC-30. MICROGLIA/BRAIN MACROPHAGES PROMOTE GLIOMA GROWTH BY EXPRESSING GLYCOPROTEIN NMB
Authors: Yalcin Fatih , Buonfiglioli Alice , Efecan Efe Ibrahim , Haneke Hannah , Kuhrt Leonard D , Synowitz Michael , Nickl Bernadette , Bader Michael , Kettenmann Helmut , Dzaye Omar 
Published: November 2019

Abstract

BACKGROUND
Glioma-associated microglia and blood-derived macrophages (GAMs) promote tumor growth in experimental mouse glioma models. Using microarray and RNA sequencing, we have previously shown that GAMs upregulate the expression of Glycoprotein NMB/Osteoactivin (GPNMB) when compared to naïve microglia. GPNMB is a type 1 transmembrane glycoprotein expressed intracellularly under healthy conditions. Malignancies such as glioma induce a translocation into the plasma membrane where the extracellular domain can be cleaved and released.

METHODS
We used qRT-PCR, immunocytochemistry, Western Blot and flow cytometry to determine the cellular localization of GPNMB expression in human and mouse glioblastoma. To test the impact of microenvironment-derived GPNMB on glioma growth, we inoculated GL261 and RCAS-PDGFb glioblastoma cells into organotypic brain slices obtained from wildtype and GPNMB-/- mice. In addition, we quantified glioma growth after injection of RCAS-PDGFb cells into wildtype and GPNMB-/- mice. The soluble extracellular domain of GPNMB was used to stimulate primary human glioblastoma and RCAS-PDGFb cells in vitro. SRB assays were performed to assess proliferation.

RESULTS
Our data indicate that GAMs are the predominant source of GPNMB in both human and mouse glioblastoma and that the levels of expression in GAMs in the tumor microenvironment is higher than in naïve microglia. In the organotypic brain slice model we found that tumors were significantly smaller in slices derived from GPNMB-/- mice as compared to wildtype. The tumor growth in vivo was nearly completely blocked in the absence of GPNMB. Stimulation of glioma cells with the extracellular domain of GPNMB did not increase proliferation.

CONCLUSION
Our results show that GPNMB is predominantly expressed in GAMs of human and murine samples. Loss of GPNMB impaired tumor growth ex vivo and glioblastoma progression in vivo. GPNMB seems to play a crucial role in the pro-tumorigenic activity of microglia and blood-derived macrophages in the tumor microenvironment.
ACTR-66. A PHASE 1, OPEN-LABEL, PERIOPERATIVE STUDY OF IVOSIDENIB (AG-120) AND VORASIDENIB (AG-881) IN RECURRENT IDH1 MUTANT, LOW-GRADE GLIOMA: UPDATED RESULTS
Authors: Mellinghoff Ingo , Cloughesy Timothy , Wen Patrick , Taylor Jennie , Maher Elizabeth , Arrillaga-Romany Isabel , Peters Katherine , Choi Changho , Ellingson Benjamin , Lin Alexander , Thakur Sunitha , Nicolay Brandon , Lu Min , Le Kha , Yin Feng , Tai Feng , Schoenfeld Steven , S Pandya Shuchi , Hassan Islam , Steelman Lori , Clarke Jennifer 
Published: November 2019

Abstract

BACKGROUND
Ivosidenib (AG-120, IVO) is a first-in-class oral inhibitor of mutant isocitrate dehydrogenase 1 (mIDH1), and vorasidenib (AG-881, VOR) is an oral, potent, brain-penetrant inhibitor of mIDH1/2. Both have been evaluated in glioma patients in ongoing phase 1 studies. In orthotopic glioma models, IVO and VOR reduced 2-hydroxyglutarate (2-HG) levels by 85% and 98%, respectively, despite different brain-to-plasma ratios (< 0.04 vs 1.33).

METHODS
Patients with recurrent, nonenhancing, WHO-2016 grade 2/3, mIDH1-R132H oligodendroglioma or astrocytoma undergoing craniotomy were randomized 2:2:1 to IVO 500mg QD, VOR 50mg QD, or no treatment (cohort 1), or 1:1 to IVO 250mg BID or VOR 10mg QD (cohort 2), for 4 weeks preoperatively. Postoperatively, patients continued receiving IVO or VOR (control patients were randomized 1:1 to IVO or VOR). Tumors were assessed for mIDH1 status, cellularity, and 2-HG and drug concentrations. Treated subjects were compared with controls and mIDH1/wild-type banked reference samples. Primary endpoint: tumor 2-HG concentration following IVO or VOR.

RESULTS
As of March 1, 2019, 27 patients (18 men; 25/2 grade 2/3) were randomized preoperatively in cohort 1 (IVO 10, VOR 12, untreated 5): 27 received drug (IVO 13, VOR 14); 1 discontinued VOR postoperatively due to disease progression. Of 26 tumors analyzed, 22 were evaluable. Mean brain-to-plasma ratios: 0.13 IVO, 1.59 VOR. Relative to untreated samples, IVO and VOR reduced tumor 2-HG by 92.0% (95% CI 73.2, 97.4) and 92.5% (95% CI 78.1, 97.7), respectively. Common (≥ 4 patients) TEAEs (all cohort 1 patients, all grades): diarrhea (37.0%), constipation, hypocalcemia, and nausea (each 18.5%), anemia, hyperglycemia, pruritus, headache, and fatigue (each 14.8%). Cohort 2 has completed accrual, with analyses ongoing.

CONCLUSIONS
In cohort 1 of this phase 1 perioperative study, IVO and VOR demonstrated brain penetrance and lowered 2-HG compared with controls. Updated data from both cohorts will be presented.
TMIC-39. DEVELOPMENT OF CD11b TRACER FOR THE IMMUNE PET IMAGING IN GLIOBLASTOMA MODEL - COULD BE A GAME CHANGER FOR IMMUNOTHERAPY APPROACHES
Authors: Nigam Shubhanchi , McCarl Lauren , Kumar Rajeev , Anderson Carolyn , Edwards Barry , Kohanbash Gary 
Published: November 2019

Abstract
Glioblastoma is a lethal brain tumor, heavily infiltrated by tumor-associated myeloid cells (TAMCs). As up to 30% of a glioma cellular mass may be attributed to immunosuppressive myeloid cells, including myeloid-derived suppressor cells (MDSCs) and tumor-associated macrophages (TAMs). TAMCs impede natural and immunotherapy-driven anti-tumor responses, they are a high-priority and promising therapeutic target currently being evaluated in clinical trials. Multiple preclinical and clinical trials have attempted to target these cells, however monitoring of biologic responses to therapy remains a challenge. Quantifying real time status of MDSCs and TAMs at the tumor site using non-invasive immunoPET could improve therapeutic response and allow for better patient stratification and monitoring of targeted treatment responses. TAMCs highly expressed the cell surface marker, integrin CD11b (Mac-1, αMβ2) and may be a highly effective imaging target for immunoPET strategies. The human/mouse cross-reactive anti-CD11b antibody (clone M1/70) was radiolabeled with 89Zr for PET imaging. PET/CT imaging, with or without a blocking dose of anti-CD11b Ab, was performed in mice bearing established orthotopic syngeneic GL261 gliomas. Flow cytometry and histology in tissues collected from post-imaging biodistribution validated targeting of CD11b+ MDSCs and TAMs. There was significant Zr-89-anti-CD11b Ab uptake in the tumor ipsilateral right brain (SUVmean = 2.6 ± 0.24) compared to contralateral left brain (SUVmean = 0.6 ± 0.11). Blocking with 10-fold lower specific activity 89Zr-anti-CD11b Ab reduced the SUV in right brain with (SUVmean = 0.11 ± 0.06). Immune rich organs spleen and lymph nodes showed high uptake. These results correlated with biodistribution analysis. CD11b expression in the right and left brain were validated using flow cytometry, H&E and IHC, showing high CD11b expression in the right brain. Imaging TAMs and MDSCs with 89Zr-labeled anti-CD11b Ab targeting was validated in a mouse model of malignant gliomas, demonstrating the feasibility of monitoring immune response during immunotherapy.
TMIC-50. 3D QUANTIFICATION OF DYNAMIC CYTOKINE GRADIENTS PRODUCED BY PRIMARY TUMOR MODELS
Authors: McGhee Eric , Uruena Juan , McGhee Alex , Mitchell Duane , Flores Catherine , Gregory Sawyer W 
Published: November 2019

Abstract

BACKGROUND & SIGNIFICANCE
The immune response is a coordinated effort directed by cytokine gradients and concentrations. High sensitivity and spatial resolution are necessary to resolve cytokine gradients in 3-dimensions. This system uses in situ confocal fluorescent microscopy with printed bead-based immunoassays. The combination of 3D printing of the beads and biofabrication of patient derived tumors allows for direct imaging, quantification, and movies of tumor cytokine secretion in response to challenges from immune cells, tumor associated fibroblasts, and chemotherapeutic agents. HYPOTHESIS: Cytokine dynamics can be measured in real-time by balancing concentrations of detection antibodies in solution with stationary immunoassay beads with measured capture and release rates. Favorable balancing of assay kinetics can facilitate measurements of concentrations of cytokines between 50 pg/mL to over 2,000 pg/mL.

METHODS
In situ confocal fluorescent microscopy identifies position, fluorescence, and type of bead relative to the in vitro tumor. Cytokines including IL2, IL6, IL8, IL11, and IFNg and growth factors such as VEGF and TGFb have been measured for a wide range of solid tumors (brain, sarcoma, and epithelial) under different stresses.

RESULTS
Dynamic gradients of IL8 were found across multiple tumor models showing local concentrations in excess of 2,000 pg/mL. Production rates were estimated to be over 1 protein per second for each cell, and inclusion of cancer associated support cells showed 10x increases in some cytokines. CD4+ cell production of IL2 was confirmed and quantified and showed strong sensitivity to tumor activity and antigen presentation. Multiplexed beads of CCL2, CCL5, CXCL8, CXCL9, and CXCL10 allow for simultaneous measurement of multiple chemokines. Uncertainties associated with fluorescence measurement and quantification of concentrations will be discussed.

CONCLUSIONS
This integrated system of 3D assay printing, biofabrication of tumors and immune cell constructs, and in situ confocal microscopy provides the first direct measurements of 3D cytokine gradients in response to tumor stress.
TMIC-59. INVESTIGATING PHYSIOLOGY OF THERAPY RESISTANT, TUMOR-INITIATING GBM CELLS IN HYPOXIC NICHES USING SPATIALLY-SENSITIVE HYPOXIA REPORTER SYSTEM AND SINGLE-CELL RNA SEQUENCING
Authors: Sattiraju Anirudh , Marallano Valerie , Friedel Roland , Zou Hongyan 
Published: November 2019

Abstract
Glioblastoma (GBM) is the most common and lethal brain cancer that invariably recurs after therapy due to presence of resistant GBM cells within hypoxic and peri-necrotic regions. Eradicating such GBM cells, which constitute a major source of tumor recurrence, is important to curb disease relapse. An endogenously expressed, spatially sensitive hypoxia reporter would therefore be a valuable tool to evaluate hypoxic zones in GBM in detail, and to measure the efficacy of hypoxia-activated drugs. For this purpose, we engineered a lentiviral vector that carries a hypoxia reporter, consisting of HIF response elements (HRE) that drive expression of UnaG fluorescent protein, which fluoresces independent of oxidative maturation. We validated the sensitivity of our reporter in vitro using U87MG, GBM2, and patient-derived GBM stem cell lines, and we performed intracranial transplantations of GBM cells in SCID mice to identify cells undergoing hypoxic stress in in vivo microenvironment. In addition, GL261 murine GBM cells with hypoxia reporter were intracranially implanted in C57BL/6 mice as syngeneic model for studies on immune responses. Brains from our transplant studies were dissociated and single-cell RNA sequencing (Drop-Seq) was performed to investigate heterogeneity in response to hypoxia within GBM cells and the cellular composition of microenvironment. We will also apply a hypoxia-activated prodrug, Evofosfamide (Evo), in our ongoing studies that can potentially eradicate hypoxic tumor cells and increase T cell infiltration and reverse immune suppression. As hypoxic niches are thought to confer resistance to radiation therapy (XRT), combining XRT with Evo could thus improve therapy efficacy. Our hypoxia gene reporter, combined with single-cell transcriptomics, could therefore serve as an effective tool to enable fundamental investigation of GBM microenvironment and could be used to evaluate therapies targeting tumor microenvironment to enhance GBM patient survival.
TMOD-13. MODELING THE GENETIC, TRANSCRIPTOMIC, AND CELLULAR HETEROGENEITY OF GLIOBLASTOMA USING TUMOR ORGANOIDS
Authors: Zhang Daniel , Jacob Fadi , Salinas Ryan , Nguyen Phuong , Ming Guo-li , Song Hongjun 
Published: November 2019

Abstract
Glioblastoma exhibits enormous genetic, transcriptional, and cellular heterogeneity at the macroscopic level across regions of the tumor as well as at the microscopic level between neighboring cells, all of which present significant challenges towards creating a definitive treatment for this devastating disease. We have developed a method of generating glioblastoma organoids (GBOs) from fresh tissue obtained directly from surgical resection and maintaining them in a defined medium without bFGF/EGF. Whole exome sequencing revealed that GBOs maintain the genomic landscape of their parent tumors. Somatic and copy number variants are present in the GBOs at similar allele frequencies or copy ratios as in the parent tumor, suggesting that the relative proportions of clonal populations are largely maintained in the organoids. Bulk transcriptomic analysis demonstrated strong gene expression correlations between the parent tumor and corresponding GBOs through 12 weeks of culture. Some tumors were sampled at multiple different anatomic regions, and the corresponding GBOs maintained region-specific gene expression signatures and genomic variants. EGFRvIII, a tumor-specific variant targeted in a number of emerging therapies, also remains present in the GBOs at similar transcript frequencies, reflecting the native heterogeneity of the parent tumor. Finally, we used single cell transcriptomics to examine cellular heterogeneity and find that GBOs contain many different cell types that exhibit similar gene expression profiles as the matching cell type in the corresponding parent tumor. Notably, these GBOs retain neoplastic as well as non-neoplastic cells, such as tumor associated macrophages / microglia, T-cells, endothelial cells, stromal cells, and oligodendrocytes. These GBOs preserve complex tumor heterogeneity an in vitro environment, creating opportunities for extended manipulation, characterization, and functional study for mechanistic investigation and therapeutic testing.
TMOD-22. LOSS OF PTEN AND TRP53 IN OLIGODENDROCYTE PROGENITORS LEADS TO GLIOMA FORMATION
Authors: Verma Ravinder , Lu Richard 
Published: November 2019

Abstract
Tumor suppressors PTEN and TP53 are the most commonly mutated anti-oncogenes in human gliomas after TERT mutation. 38% and 17% of total 4023 samples of gliomas in TCGA show TP53 and PTEN mutations respectively. TP53 signaling pathway plays an important role in the suppression of tumor progression PTEN negatively regulates PI3 triphosphate levels and suppresses AKT/PKB pathways. In-frame and missense mutations in PTEN constitutively activates the proliferative pathway and give a survival advantage. Mice with conditional mutation of PTEN and TP53 in neural stem cells directed by hGFAP-Cre develop high-grade gliomas. Our recent study indicates that primitive oligodendrocyte-progenitor intermediates (Pri-OPC) are abundant and hyperproliferative cells and can be progressively reprogrammed towards a stem-like state susceptible to malignant transformation. We hypothesize that mutations in PTEN and TP53 in pri-OPC lineage cells can lead to glioma formation. OPCs distribute across the whole adult brain and exhibit a much higher number than NSCs that are restricted to very small niche areas. Olig1 and Olig2 mark pri-OPC and oligodendrocyte lineage cells. In this study, we inactivated the PTEN/TP53 gene in mouse pri-OPCs using Olig1-Cre or Olig2tva-Cre. The incidence of glioma formation was 100%. Both the tumor formed in these models display multifocal, high-grade, diffuse and infiltrating gliomas. Though tumors are derived from similar cell sources, they vary in the expression and extent of oncogenic pathways. Our transcriptomics profiling at different stages of tumorigenesis reveals that progressive activation of oncogenic signaling pathways establishes a tumorigenic state to promote malignant transformation, suggesting a dynamic process of tumorigenesis caused by the cooperative action of the PTEN and TP53 loss in the pri-OPC lineage.
TMOD-34. A RADIOMIC SIGNATURE OF INFILTRATION IN PERITUMORAL EDEMA PREDICTS SUBSEQUENT RECURRENCE IN GLIOBLASTOMA
Authors: Rathore Saima , Shukla Gaurav , Akbari Hamed , Sako Chiharu , Bilello Michel , Mohan Suyash , Badve Chaitra , Barnholtz-Sloan Jill , Sloan Andrew , Lustig Robert , Davatzikos Christos 
Published: November 2019

Abstract

BACKGROUND
The malignant parenchyma in glioblastoma extends beyond the enhancing borders of tumor on postcontrast T1-weighted magnetic resonance imaging (MRI), which is the primary target of treatment. Such non-enhancing tumor invasion into the peri-tumoral edema (PED) is, however, not usually distinguishable on conventional MRI. The aim of this study was to evaluate pre-operative MRI in the PED to assess whether areas of tumor infiltration and early recurrence can be detected.

METHODS
A cohort of 90 de novo glioblastoma patients from a single institution (Penn) was selected. All included patients had preoperative multi-parametric MRI (mpMRI;T1,T1Gd,T2,T2-FLAIR,ADC), underwent initial gross-total-resection followed by standard chemoradiation, and had pathologically-confirmed recurrence. An extensive panel of handcrafted features, including shape, volume, intensity distributions, texture, was extracted from mpMRI scans. Predictive modeling for estimation of PED infiltration was performed using sequential feature selection approach designed with a support vector machine classifier and through a Leave-one-out cross-validation approach in the Penn cohort. Generalizability of the model was evaluated by applying it on a cohort of 20 patients from a second institution (Case), and predicted probability distributions in PED were compared in both the cohorts.

RESULTS
Spatial probability maps, representing the likelihood of tumor infiltration and eventual recurrence, were binarized at 50% cutoff, and compared with actual recurrence on post-recurrence scans. The cross-validated accuracy of our model within Penn cohort was 81.35% (odds-ratio=3.62, sensitivity/specificity=78.26/81.35). The model trained on the Penn cohort, when applied on the Case cohort, produced almost similar intensity distribution in the PED, suggesting that the method has potential for robust performance across institutions. The comparison of intensity distributions revealed higher ADC and T2-FLAIR in non-recurrent regions compared to recurrent ones.

CONCLUSION
Multi-parametric pattern analysis of mpMRI across multiple institutions generates similar, accurate estimates of spatial extent and patterns of recurrence in PED, which may guide strategies for treatment intensification in glioblastoma.
SCIDOT-17. UNDERSTANDING THE EFFECTS OF MOLECULAR SIZE ON VOLUME OF DISTRIBUTION IN CONVECTION-ENHANCED DELIVERY
Authors: Rechberger Julian S , Power Erica A , Zhang Liang , Olson Ian , Lu Victor M , Daniels David J 
Published: November 2019

Abstract
Diffuse midline gliomas harboring the H3K27M mutation, previously known as diffuse intrinsic pontine gliomas (DIPG), are rare and aggressive pediatric brain tumors without cure. One of the major challenge sin DIPG treatment is the effective delivery of therapeutic agents across the blood-brain barrier (BBB) to the tumor and surrounding infiltrating cells. Therefore, strategies that enhance drug delivery to the brain are of great interest. Convection-enhanced delivery (CED) is a technique that bypasses the BBB and increases drug distribution by applying hydraulic pressure to deliver compounds directly and evenly into a target region. However, knowledge in CED pharmacology and convective kinetics is still lacking. In an effort to characterize the feasibility, safety, and distribution in the brain based on molecular size of the delivered agent, we performed infusions of FITC-dextran (range 3,000 Da–150,000 Da) comparing CED and osmotic pump-based delivery into the brainstem of rodents. We calculated the area and volume of distribution (Vd) of the FITC-dextran throughout the brain. Our data showed that the Vd decreased exponentially with increased molecular weight of the FITC-dextran. Interestingly, the Vdcan maintain linearity at lower molecular weights. Maximal cross-sectional area and craniocaudal extension of fluorescence also decreased when lowering the infusate size. In addition, we developed a patient-derived DIPG orthotopic xenograft model and performed an image-guided CED cannula installation in the tumor bed. Using 3D bioluminescence imaging and computed tomography, we determined the tumor volume and the positioning of the cannula in the bulk tumor. The summation of these results supports CED as a promising technique for treating DIPG tumors. A better understanding of how drugs distribute by convection will allow us to optimize treatment regimens and, ultimately, offers hope to patients and families with this devastating disease.