bluuebunny/crossref_metadata_2025_split huggingface dataset:
EXTH-49. BXQ-350 TARGETS TO THE LYSOSOME AND KILLS GLIOBLASTOMA (GBM) CELLS VIA ACTIVATION OF APOPTOTIC CASPASES IN VITRO
Authors: Wilkins Nikhil , Stephens Timothy , Felix Laura 
Published: December 2020

Abstract

BACKGROUND
Apoptosis is a programmed cell death mechanism where cells respond to internal or external stimuli by initiating a cascade of events and enzymes leading to cell death. One of the hallmarks of cancer is the ability to resist apoptotic stimuli. Removing resistances to apoptosis can result in the death of these tumor cells.

METHOD
The GBM cell line Gli36ΔEGFR was used to determine Caspase activity and BXQ-350 cytotoxicity. Cells were treated with 9uM to 30uM BXQ-350 in triplicate and incubated for 24 hours at 37oC. Promega’s Caspase-Glo 9 or Caspase-Glo 3/7 reagent was added to each well of a plate and was incubated at room temperature in the dark for 3 hours then luminescence was read. The parallel cytotoxic assay was run under the same conditions except Roche’s MTT labeling reagent was added to each well after 24 hours and the plate was incubated at 370C for 4 hours. Solubilization solution was added to each well, the plate was incubated overnight then absorbance was read. The GBM cell line U87 MG was used to determine lysosomal targeting by treating with 10uM BXQ-350 and incubated at 37oC overnight. They were stained with anti-SapC (RFP) and anti-LAMP1 (GFP) antibodies and images were taken.

RESULT
BXQ-350 mediated cell death is correlated with a rise in Caspase 3, Caspase 7 and Caspase 9 activity. The caspase activity levels did not rise until after BXQ-350 passed its IC50 and stayed elevated. Caspases 3/7 levels showed higher activity compared to untreated than Caspase 9. BXQ-350 was seen to colocalize to LAMP1, a lysosomal membrane protein.

CONCLUSION
BXQ-350 tracks to the lysosomal membrane where it initiates a cascade of enzymes necessary to cause apoptosis. Caspases 3/7 are the effector caspases that complete the apoptotic process removing a major barrier to fight cancer.
EXTH-56. DISRUPTION OF FUNCTIONAL NETWORKS IN GLIOBLASTOMA TO OVERCOME THERAPY RESISTANCE
Authors: Joseph Kevin , Vollmer Lea , Schneider Matthias , Beck Juergen , Hofmann Ulrich , Schnell Oliver , Heiland Dieter 
Published: December 2020

Abstract
Neurobeachin plays a crucial role when it comes to the formation, maturation, and differentiation of functional synapses, within the central nervous system (CNS). Glioblastoma has cellular compartments that have been shown to form functional synapses, integrating themselves to existing neuronal networks. We present evidence that GBM cells form electrophysiologically active networks, mediated by both electrical and chemical synapses during their growth. These networks carry information about changes in the tumor microenvironment, similar to those observed in neuronal networks. We present data about signature signaling patterns, dependent on stimuli, leading to transcriptional changes. These patterns are conducted through the network by means of electrical/chemical synapses, mediated by Neurobeachin. When the tumor network was acutely treated with a signaling inhibitor, Meclofenamate, functional synapses were altered, leading to an abolishment of electrical signaling, resulting in loss of biological organization. These results were validated in both extracellular electrophysiological recordings and Ca2+ imaging experiments. The formation of these functional networks plays a vital role in the resistance to alkylating agents or harsh metabolic imbalances, which was completely lost when the network was disrupted. Acute downregulation of Neurobeachin expression causes electrophysiological disruption of the GBM network, leading to loss of connectivity, terminally resulting in cell apoptosis/necrosis, transcriptionally validated by means of RNA-seq. This combined therapeutic approach could lead to potential alternative therapy, where the basic biological functionality of the GBM is targeted.
EXTH-58. ONCOSCILLATORS: INDUCTION OF THE MITOCHONDRIAL PERMEABILITY TRANSITION IN CANCER CELLS
Authors: Sharpe Martyn , Baskin David , Helekar Santosh 
Published: December 2020

Abstract
Magnetic fields in the mT range influence spin state pairing in redox-active radical pairs generating spin-forbidden quantum states which are kinetically inert. Studies examining the effects of static magnetic fields on mitochondrial electron transfer kinetics have demonstrated only modest effects. When neodymium super-magnets are securely attached to and precision-balanced on the shafts of electronically-controlled motors it is possible to generate rotating magnetic fields of desirable strengths and frequencies. Unlike a static magnetic field or an alternating field in a static electromagnetic coil, oscillating magnetic field (OMF) produced by rotating lines of force of a spinning permanent magnet can dynamically couple the electron spins of radical pairs within proteins whose orientations are ‘fixed’. The frequencies of rotation of magnets can also be tuned to appropriate electron cycling resonances within the proteins. Using OMF of appropriate field strength, frequency and on/off acceleration/deceleration profiles we can completely arrest electron transport in isolated respiring rat liver mitochondria. Parallel to this inhibition of electron flux, we also independently observe an increase in superoxide and hydrogen peroxide. Under certain OMF exposure regimes, we observe membrane permeability transition in these mitochondria when using succinate as substrate, and show that the mitochondrial membrane permeability transition effect can be blocked by bongkrekic acid. We have examined the effect of OMF on oxygen consumption in cultured primary cancer cells with a rotating magnet (oncoscillator) that is an integral component of a new anti-cancer Oncomagnetic device. We observe three main effects in addition to the inhibition of respiratory flux in cancer cells – damage to the respiratory complex, uncoupling and generation of superoxide/hydrogen peroxide. OMF generated by oncoscillators can induce mitochondrial permeability transition in primary cultured malignant meningioma, diffuse intrinsic pontine glioma and GBM cells. Parallel experiments with normal human astrocytes show only minor changes in cellular/mitochondrial function under these conditions.
EXTH-63. IN VITRO DRUG SCREENING BASED ON IN SILICO DATA IDENTIFIES NEW THERAPEUTIC AGENTS FOR AGGRESSIVE MENINGIOMA
Authors: Jungwirth Gerhard , Cao Junguo , Yu Tao , Warta Rolf , Unterberg Andreas , Herold-Mende Christel 
Published: December 2020

Abstract
The mainstay of treatment for progressive or recurrent meningiomas is surgery and/or radiotherapy. Patients with refractory cancer might benefit from systemic treatment options. However, to date, no effective chemotherapy is available for these patients. For this reason, novel inhibitors for the treatment of aggressive meningiomas are urgently needed. Therefore, we used our previously published Affymetrix microarray dataset (GSE74385) consisting of 62 meningiomas enriched with 28 WHO°III MGMs to screen substantially expressed genes that can be targeted by available inhibitors. For each targeted gene, three compounds were selected based on their clinical development. This filter process resulted in 107 drugs targeting 57 different genes. Most compounds were oncology-related (n = 94, 88%) with the remaining compounds being non-oncology agents (n = 13, 12%). Thereafter, a 2-stage screening strategy was employed. First, drugs were screened at a single dose (2.5 µM) in two malignant meningioma cell lines (NCH93 and IOMM-Lee) with CellTiter-Glo (Promega). Only drugs resulting in a cell viability of 50% or less of either cell line were considered for further validation. Remaining drug candidates (n = 33) exclusively belonged to the oncology-related group, consisting of 4 FDA-approved antineoplastic drugs (12%). The other drugs are currently tested in clinical trials (24% in phase III, 39% in phase II, and 24% in phase I). Drug candidates were further analyzed in a six-point dose-response scheme ranging from 0.1 nM to 10 µM in three meningioma cell lines (Ben-Men-1, NCH93, IOMM-Lee). The top 5 drugs were selected based on the lowest mean of z-transformed area under the curve. Resulting drugs and corresponding targets are: OTSSP167 (MELK), Panobinostat (HDAC), Picropodophyllin (IGF-1R), KPT-9274 (PAK4 and NAMPT), and BI-2536 (PLK1). Taken together, our drug screening approach utilized in silico data to identify potential inhibitors for the treatment of aggressive meningiomas warranting further preclinical investigation.
EXTH-66. NEO100 TRANSIENTLY OPENS UP THE BLOOD BRAIN BARRIER VIA TIGHT JUNCTION INHIBITION
Authors: Chen Thomas , Wang Weijun , Ramos Nagore Marin , Schonthal Axel 
Published: December 2020

Abstract
The blood brain barrier (BBB) prevents effective entry of nearly all therapeutics to the central nervous system (CNS), preventing effective treatment of brain-related malignancies. Intracarotid mannitol injection has been the main technique to transiently open up the BBB, with its attendant variability and complications. A more direct and better tolerated method is needed to open up the BBB. We present our discovery that intraarterial (IA) injection of NEO100, a cGMP-quality form of perillyl alcohol (POH), transiently opens up the BBB in a safe and reversible manner. We used in-vitro models of MDCK1 and patient derived brain endothelial cell (BEC) + astrocyte barriers to determine that NEO100 increased FITC-antibody diffusion across the in-vitro BBB model and decreased trans-epithelial/endothelial electrical resistance (TEER). NEO100 effects on transcellular and paracellular pathways were studied using western blot, flow cytometry, HPLC, fluorescent probes, microarray analysis, and transmission electron microscopy. In-vivo studies were performed using ultrasound-guided intracardiac administration of NEO100 in mice with subsequent intravenous delivery of non-BBB permeable therapeutic agents. We determined that NEO100 transiently disrupts the transcellular pathway by permeabilizing BEC membranes, and the paracellular pathway via delocalization of tight junction proteins. In vivo IA NEO100 administration caused an effective dose- and time-dependent BBB permeabilization, which was reversible and well tolerated by the mice. This was evidenced by the spreading of Evans blue dye, and of therapeutics with different molecular weights, ie methotrexate, anti-PD-1 antibody, and CAR-T cells in the brain. Our results demonstrate that IA NEO100 is able to open the BBB in a controlled and reversible manner, allowing it to facilitate drug delivery to the CNS.
EXTH-74. IND-ENABLING CHARACTERIZATION OF DUAL DRD2- AND ClpP-TARGETING AGENT ONC206 AS THE NEXT IMIPRIDONE FOR CLINICAL NEURO-ONCOLOGY
Authors: Prabhu Varun , Morrow Sara , Kawakibi Abed Rahman , Jitkova Yulia , Jung Jinkyu , Madhukar Neel , Garnett Mathew , McDermott Ultan , Benes Cyril , Wechsler-Reya Robert , Elemento Olivier , DeMorrow Sharon , Schimmer Aaron , Stogniew Martin , Theeler Brett , Gilbert Mark , Allen Joshua 
Published: December 2020

Abstract
ONC201 is the first bitopic antagonist of dopamine receptor D2 (DRD2) and allosteric mitochondrial protease ClpP agonist, that is well tolerated and induces durable tumor regressions in H3 K27M-mutant glioma patients. ONC206, a derivative of ONC201, is also a bitopic DRD2 antagonist that exhibits enhanced non-competitive effects, nanomolar potency, and disruption of DRD2 homodimers. In these studies, a FITC-casein degradation assay revealed that ONC206 also acts as an agonist of human ClpP and has a 3-fold improved potency. GEPIA database analysis showed ClpP mRNA was overexpressed in glioblastoma cells relative to normal cells. Broad nanomolar efficacy of ONC206 (GI50 &lt; 78-889nM, 72h) was observed in &gt;1,000 GDSC cancer cell lines with the highest sensitivity in cell lines exhibiting high ClpP and/or DRD2+/DRD5- RNA expression signatures. Among solid tumors, nervous system related cell lines were particularly sensitive. ONC206 reduced the viability of normal human fibroblasts at higher doses (GI50 &gt; 5µM), suggesting a wide therapeutic window. Antitumor efficacy without body weight loss was observed with 50 mg/kg weekly oral ONC206 in a subcutaneous xenograft model of DRD2-overexpressing, dopamine-secreting tumor cells. Oral ONC206 at 50mg/kg exhibited a ~12 µM plasma Cmax and ~6 hours terminal half-life in Sprague-Dawley rats. Additionally, 5–10 fold higher ONC206 concentrations were observed in adrenal gland, bile duct, brain and bone marrow relative to plasma. GLP toxicology studies with weekly oral ONC206 in Sprague-Dawley rats and beagle dogs revealed no dose-limiting toxicities. Mild and reversible body weight changes were observed at the highest evaluated dose in both species. The no-observed-adverse-effect level was ≥ 16.7 mg/kg in dogs and ≥ 50 mg/kg in rats that exceed efficacious doses. A 50 mg starting dose of ONC206 was selected for the first-in-human open label, dose escalation, and food effect Phase I study in biomarker-enriched adult recurrent primary CNS tumors.
EXTH-75. IN VITRO AND IN VIVO EFFICACY OF COMBINATORIAL INHIBITION OF LSD1 AND HDACS IN PATIENT DERIVED GLIOBLASTOMA STEM CELL MODELS
Authors: Gangadharan Achintyan , Grasse Leslie , Espejo Alexsandra , Ezhilarasan Ravesanker , Collier Tiara , Henry Verlene , Gumin Joy , Sulman Erik , Lang Frederick , Chandra Joya 
Published: December 2020

Abstract
Inhibitors of histone deacetylases (HDACi) have been tested in glioblastoma (GBM), however, single agent clinical efficacy has not been proven, prompting study of combinatorial approaches. A rational HDACi combination strategy is with inhibition of LSD1, lysine specific demethylase 1, a histone demethylase known to exist in complex with HDAC1/2. We previously showed in vivo efficacy of combining a brain permeant LSD1 inhibitor, tranylcypromine (TCP) together with vorinostat. More selective inhibitors of LSD1 have been developed and were tested in the current study together with the HDACi, vorinostat or panobinostat in a panel of patient derived glioblastoma stem cell (GSC) lines that have been characterized as radio-resistant or radiosensitive. To test in vitro sensitivity, dose response experiments were conducted in nine GSC cell lines using three LSD1 inhibitors or two HDACi as single agents or in combination. Two non-tumor lines were also tested to assess selective cytotoxicity for brain tumor lines. Cell viability and clonogenicity assays were performed. Several radio-resistant GSC lines showed sensitivity to single agent LSD1 inhibitors, whereas some radio-sensitive GSCs did not, indicating distinct molecular mechanisms of response. Intracranial orthotopic xenograft models were used to test in vivo efficacy using the radioresistant GSC20 line. Interestingly, LSD1 inhibition alone promoted tumor burden reduction and better survival rates than combination treatment. RNA-Seq guided biomarkers of sensitivity to the LSD1/HDAC inhibitor combination were assessed in vitro and in vivo. Both in vivo and in vitro data show that GSC20 treated with GSK LSD1 inhibitor had higher levels of HKDC1 gene with in vivo data also showing elevated levels of FTH1. In vivo mouse data for vorinostat and combination treatment groups showed that only the FTH1 gene level was elevated, providing a potential explanation for low in vivo efficacy. Collectively, our data suggests that LSD1 inhibition represents a viable strategy in GBM.
EXTH-76. THE INOVIVO SYSTEM: A NOVEL PRECLINICAL TOOL FOR IN VIVO DELIVERY OF TUMOR TREATING FIELDS (TTFIELDS)
Authors: Davidi Shiri , Blat Roni , Shteingauz Anna , Porat Yaara , Giladi Moshe , Weinberg Uri , Palti Yoram 
Published: December 2020

Abstract
Tumor Treating Fields (TTFields) are an antineoplastic treatment modality targeting dividing cancer cells, approved by the FDA for treatment of glioblastoma and malignant pleural mesothelioma. TTFields are delivered to the patient continuously, using a portable signal generator and 2 pairs of transducer arrays attached to the skin. While in vitro research tools for TTFields have been available, animal experiments were so far limited due to the lack of a dedicated TTFields in vivo delivery system. The main challenges associated with TTFields application to mice are the absolute requirement for adequate and continuous contact between array electrodes and animal skin throughout treatments; and the need to deliver the electric fields through multiple wired conductors connected to electrodes, which limit animal movement thus imposing stress. This work reports on development of an in vivo system to facilitate continuous delivery of TTFields to mice bearing cancer tumors in the torso or flank that addresses the aforementioned challenges. Three major developments were introduced to the system: 1) transducer array electrodes composed of delicate, flexible inner layer to improve skin adherence and a breathable, durable, outer layer to secure electrodes to the skin; 2) a novel electric swivel to prevent cable coiling; and 3) a cage constructed to house 2 mice separately while still allowing socializing. During a 1-week study, the new inovivo system demonstrated improvement compared to previous systems in the following areas: increased animal treatment compliance, less weight loss, and fewer number of array replacements. In conclusion, the new inovivo system is a comprehensive tool for continuous, 2 directional TTFields delivery to tumors in the torso or flank of mice for conducting TTFields experiments with minimal animal stress, thus allowing further elucidation of the effects of TTFields on the whole animal.
IMMU-02. THE SURVIVAL OUTCOMES ASSOCIATED WITH IMMUNE CHECKPOINT INHIBITORS FOR NON-SMALL CELL LUNG CARCINOMA PATIENTS WITH BRAIN METASTASES IN THE UNITED STATES
Authors: Lamba Nayan , Smith Timothy , Iorgulescu Bryan 
Published: December 2020

Abstract

BACKGROUND
Management of advanced NSCLC has been transformed by PD-1/PD-L1 immune checkpoint inhibitors (ICI), with FDA approvals in 2015 (second-line) and 2016 (first-line). Because patients with brain metastases (BMs) were disproportionately excluded from the pioneering trials, herein we evaluated the overall survival (OS) associated with ICI in NSCLC BMs nationally.

METHODS
Patients newly-diagnosed with stage 4 NSCLC, including BMs, from 2010–2016 were identified from the National Cancer Database (comprising &gt;70% of all newly-diagnosed cancers in the U.S.) Post-approval, median time from diagnosis to ICI was 58days, and this timepoint was selected for all landmark survival analyses (logrank test and multivariable Cox regression) and for multivariable logistic regression to identify predictors of ICI utilization.

RESULTS
50,858 patients presented with advanced NSCLC that involved the brain: representing 27.6% of all newly-diagnosed stage 4 cases. Following initial FDA approvals in 2015, ICI rates for BM patients rose from 7.2% in 2015 to 12.7% in 2016. OS for NSCLC BMs for patients diagnosed post-approval (median 6.3 months, 95%CI: 6.0–6.6) was substantially better than those diagnosed pre-approval (median 5.5 months, 95%CI: 5.4–5.7, p&lt; 0.001) and, in fact, than those diagnosed in 2014 (median 5.9 months, 95%CI: 5.6–6.1, p=0.002). Among patients diagnosed post-approval, ICI receipt demonstrated substantially improved OS in landmark survival analyses (median 13.8 months, 95%CI: 12.2–15.1; vs. 8.5 months, 95%CI: 8.3–8.9, p&lt; 0.001); benefits which persisted in multivariable landmark survival analyses (HR 0.83, 95%CI: 0.71–0.96, p=0.02), independent of patient characteristics, other therapies, and extracranial disease. For patients diagnosed post-approval, who reached the landmark timepoint, ICI receipt was independent of patient demographics, socioeconomic status, and hospital type—with the exception of Medicaid-insured patients, who were less likely than privately-insured patients to receive ICI (OR 0.77, 95%CI: 0.60–0.97, p=0.03).

CONCLUSIONS
Nationally, the dramatic OS benefits of ICIs for advanced NSCLC were also demonstrated for patients with BMs.
IMMU-07. TUMOR STROMA–TARGETING ANTIBODY-CYTOKINE CONJUGATES TO CONVERT THE IMMUNOLOGICALLY COLD GLIOMA MICROENVIRONMENT INTO A HOT ONE
Authors: Weiss Tobias , Puca Emanuele , Silginer Manuela , Hemmerle Teresa , Pazahr Shila , Bink Andrea , Weller Michael , Neri Dario , Roth Patrick 
Published: December 2020

Abstract
Glioblastoma is an immunological “desert”. The administration of pro-inflammatory cytokines could shift the balance between tumor-associated immune suppression and anti-tumor immunity but the systemic administration of therapeutically active doses of pro-inflammatory cytokines is hampered by toxic side effects. We investigated different antibody-cytokine fusion products that enable a targeted delivery of interleukin (IL-) 2, IL-12 or tumor-necrosis factor (TNF)α to the tumor site upon systemic administration by binding to a tumor-specific epitope of fibronectin. We confirmed the target antigen expression in ex vivo sections of orthotopic syngeneic glioma mouse models and human glioblastoma samples and characterized the distribution of these antibody-conjugates in glioma-bearing mice upon systemic administration using in vivo imaging. Subsequently, we demonstrated potent anti-tumor activity of these antibody-fusion proteins in fully immunocompetent orthotopic mouse glioma models and characterized their mode of action. We also translated this immunotherapeutic strategy to treat patients with recurrent glioblastoma systemically with an antibody-fusion protein that enables the targeted delivery of TNFα to the tumor site. This was well tolerated, led to a treatment-associated tumor necrosis and increased the number of tumor-infiltrating T cells. This work builds a basis for future studies with antibody-cytokine fusion proteins as a promising treatment strategy for central nervous system tumors.