bluuebunny/crossref_metadata_2025_split huggingface dataset:
EXTH-13. POTENT ANTICANCER EFFECTS OF A NEW WEARABLE NONINVASIVE ONCOMAGNETIC DEVICE: CELLULAR MECHANISMS OF ACTION
Authors: Helekar Santosh , Hambarde Shashank , Baskin David , Sharpe Martyn 
Published: December 2020

Abstract
Oscillating magnetic fields (OMF) produced by a new device with rotating magnets produces rapid apoptosis of patient derived glioblastoma (GBM) cells in culture. We have proposed that this is due to a sequence of events triggered by the well-established mT-range magnetic influence on the radical electron pair mechanism in the mitochondrial respiratory electron transport chain (ETC). Here we present results of preclinical studies in support of this mitochondrial hypothesis, accounting for the oncolytic effects of OMF. We tested a range of in vitro treatment protocols, involving changes in frequency and timing of OMF, to arrive at an optimally effective set of parameters. After hours of exposure to this optimized intermittent pattern of OMF killed not only patient derived GBM cells, but cells of 4 other malignant tumors in a cell culture dish. This treatment was not lethal to normal human astrocytes, bronchial epithelial cells, and B lymphocytes. Exposure to static magnetic fields and continuous OMF did not produce any oncolysis. The oncolytic effect of OMF was potentiated by compounds that enhance mitochondrial metabolism, e.g. β-hydroxybutyrate. The underlying cellular mechanism of OMF action involved complete arrest of ETC-dependent consumption of oxygen, accelerated upregulation of the levels of reactive oxygen species, opening of the mitochondrial membrane permeability transition pore, and disruption of the mitochondrial network, leading to caspase-dependent apoptosis of cancer cells. Daily treatment in a late-stage mouse model consisting of human GBM xenografts implanted into the brains of immunocompromised mice produced significant survival benefit. These findings document the potent oncolytic effects of OMF and specific mechanisms of action that will likely provide a novel and powerful treatment against GBM and a wide range of other solid malignant tumors. Clinical trials of this therapy are underway at our institution.
EXTH-18. ENGINEERED EXOSOMES AS GENE DELIVERY TOOLS FOR THE TREATMENT OF GLIOBLASTOMA
Authors: McDonald Malcolm , Hossain Anwar , Momin Eric , Hasan Irtiza , Singh Sanjay , Adachi Satoshi , Gumin Joy , Ledbetter Daniel , Daou Marc , Gopakumar Sricharan , Phillips Lynette , Kerrigan Brittany Parker , Lang Frederick 
Published: December 2020

Abstract
Although we previously showed that exosomes are capable of delivering anti-glioma microRNAs (miRs) to brain tumors (Lang et al. 2018), our studies revealed significant opportunity to 1) improve packaging and delivery efficiency of exosomes and 2) expand the repertoire of anti-glioma miRs. We hypothesized that incorporation of viral proteins into exosomes would enhance miR packaging and cell entry. To test this hypothesis, we engineered exosomes that express retroviral Gag and VSVg proteins (eExos). Specifically, HEK293T cells were transfected with Gag, VSVg, and with Cre-recombinase containing plasmid (pCre) to generate eExos-pCre. After 48hrs eExos-pCre were isolated by differential ultracentrifugation. Western analyses verified Gag and VSVg in eExos-pCre, and PCR documented pCre in these exosomes. Next, U87 cells harboring a dsRed-eGFP-loxP reporter-gene were treated with eExos-pCre or control exosomes. Flow cytometry demonstrated that eExos-pCre resulted in 82% conversion of red cells to green, compared with controls (2% conversion), verifying the effectiveness of eExos to deliver plasmids containing anti-glioma agents. To identify effective anti-glioma miRs, we conducted a high-throughput screen of 539 miRs against 7 glioma stem cell lines (GSCs) and identified miR-124-2, miR-135-a-2, and Let7i as the most potent anti-glioma miRs. We then studied the ability of eExos to package and deliver plasmids of these miRs either singly (eExos-miR-124, eExos-miR-135, eExos-miRLet7i) or as a tri-cistronic plasmid (eExos-miR-124-135-Let7i). Although eExos-miR-124, eExos-miR-135, and eExos-miRLet7i significantly decreased in vitro proliferation in all three GSCs (p&lt; 0.01), eExos-miR-124-135-Let7i were most effective (p&lt; 0.001). In in vivo studies, mice harboring GSC231 gliomas were injected with each of the eExos-miRs. Most significant improvement in survival was seen with eExos-miR-124-135-Let7i (median 75 versus 32.5 days for controls, p&lt; 0.001). We conclude that eExos are a novel delivery strategy for human gliomas and that a tri-cistronic plasmid of miR-124-135-Let7i is highly effective against GBM and worthy of clinical translation.
EXTH-19. EVALUATING THE ANTI-TUMOR EFFECT OF A NOVEL THERAPEUTIC AGENT, MAGMAS INHIBITOR, IN MALIGNANT GLIOMA
Authors: Di Kaijun , Du Senjie , Lepe Javier , Nandwana Nitesh , Das Bhaskar , Bota Daniela 
Published: December 2020

Abstract

BACKGROUNDS
Glioblastoma (GBM) is an aggressive infiltrative brain tumor, and has an extremely poor prognosis despite the use of multiple treatment modalities, including surgery, radiation, and chemotherapy. Meanwhile, mitochondrial changes represent a significant part of cancer cell biology since cancer cells must survive and adapt to challenging microenvironments, specifically in conditions where tumor growth makes oxygen and glucose scarce. As GBM is characterized by extensive hypoxia-induced phenotypic changes such as abnormal vascular proliferation and necrosis, regulation of mitochondrial function could be a novel approach for treating GBM that currently lacks effective therapies. Magmas (mitochondria-associated protein involved in granulocyte-macrophage colony-stimulating factor signal transduction) is a nuclear gene that encodes for the mitochondrial import inner membrane translocase subunit Tim16. We previously demonstrated that a novel Magmas inhibitor, BT#9, significantly exerted anti-tumor effect in glioma in vitro, and may cross the blood brain barrier in vivo, indicating that Magmas inhibitor may be a new chemotherapeutic agent for the treatment of GBM.

METHODS
In this study, the antitumor effect of Magmas inhibitor BT#9 was tested in an orthotopic xenograft model of human GBM. The molecular mechanism of BT#9 was investigated using glioma cell lines.

RESULTS
The mice were tolerated to BT#9, and there was no statistical difference in the weight of animals between the control and MTD (Maximum-tolerated Dose, 50mg/kg) groups. The immunocompromised mice, intracranially implanted with human D-54 GBM xenografts, survived significantly longer than the controls (P&lt; 0.5) when treated with BT#9 at MTD. In vitro study showed that the MAP kinase pathways are involved in BT#9-induced tumor suppression.

DISCUSSION
This is the first study on the role of Magmas in glioma in vivo. Our findings suggested that Magmas plays a key role in glioma survival and targeting Magmas by Magmas inhibitor has the potential to become a therapeutic strategy in glioma patients.
EXTH-25. THE CSF PENETRATION OF THE PROCASPASE-ACTIVATING COMPOUND (PAC-1) IN COMBINATION WITH TEMOZOLOMIDE (TMZ) IN A NONHUMAN PRIMATE CSF ACCESS MODEL
Authors: Lester McCully Cynthia , Shankarappa Priya , Garcia Rafael Cruz , Peer Cody , Zakharov Alexander , Fischer James , Lyubimov Alexander , Hergenrother Paul , Thomas Marvin , Figg William , Warren Katherine 
Published: December 2020

Abstract

BACKGROUND
The synergistic activity of temozolomide (TMZ) administered in combination with procaspase-activating compound (PAC-1) has been reported in pre-clinical mouse models and canine patients, leading to clinical trials in adults with glioblastoma. To optimize pediatric clinical trial design, a translational pharmacokinetic CSF penetration study was conducted using a pre-clinical nonhuman primate non-tumor bearing CSF access model with TMZ and PAC-1 administered alone and in combination.

METHODS
Four male rhesus macaques with CSF lateral ventricular reservoirs received PAC-1, 15 mg/kg orally [Human Equivalent Dose (HED) 558 mg/m2/day] or TMZ, 1-hr IV infusion, 7.5 mg/kg (HED 150 mg/m2) as single and combination agent administration. Paired plasma and CSF samples were collected for 0–96 hours. PAC-1 and TMZ were quantified by LC-MS/MS. Pharmacokinetic parameters were calculated using noncompartmental methods. Statistics were determined via Mann-Whitney test.

RESULTS
(Mean ± Standard Deviation): For TMZ: Plasma AUC0-24 (hr*ng/ml) single agent (n=4): 28590 ± 4888 and in combination (n=4): 32736 ± 10147. CSF AUC0-24 (hr*ng/ml) single agent (n=4):14406 ± 1279 and in combination (n=4):15614 ± 1767. CSF penetration (% AUCCSF: AUCPLASMA) single agent: 50.9% ± 2.2 and in combination:49.6% ± 8.4. For PAC-1: Plasma PAC-1 AUC0-24 (hr*ng/ml) single agent (n=4): 2556 ± 2157 and in combination (n=4): 1947 ± 1311. CSF PAC-1 AUC0-24 (hr*ng/ml) single agent (n=2): 8.7 ± 1.1 and in combination (n=3):12.9 ± 10.2. CSF penetration single agent: 0.2% ± 0.03 and in combination: 0.4% ± 0.38. CSF PAC-1 tlag and Tmax pharmacokinetic parameters decreased with concurrent TMZ administration.

CONCLUSIONS
In this non-tumor bearing pre-clinical nonhuman primate model the CSF penetration of PAC-1 was low and not notably affected by the concurrent administration of TMZ. TMZ CSF penetration for single administration was within previously reported ranges and also appeared unaffected when administered in combination with PAC-1.
EXTH-26. SECONDARY STRUCTURE ANALYSIS OF THE EGFR PRE-mRNA TRANSCRIPT TO IDENTIFY TARGETABLE REGIONS AND OPTIMIZE RNA THERAPY
Authors: Hicks Martin , Fink Ryan , Gawargi Flobater 
Published: December 2020

Abstract
Individuals diagnosed with glioblastoma multiforme (GBM) have a short life expectancy of 12–15 months. Current strategies are often limited by the blood-brain barrier. This project is to develop therapies to bypass challenges to effective and continuous drug delivery to the brain, targeting cancer-driving genes. Epidermal growth factor receptor (EGFR) is dysregulated in 57% of all GBM. Our approach uses an adeno-associated virus gene transfer vector encoding RNA therapeutics targeting critical elements of the EGFR pre-mRNA transcript. The ‘pre-mRNA structurome’ can be used to uncover and determine the accessibility of targetable regions. Our approach has the potential to deliver one single dose of gene therapy directly to the GBM tumor environment and block the production of EGFR and activate the expression of a stable therapeutic isoform of EGFR. To advance our therapeutic strategy, we have analyzed the EGFR secondary structure using selective 2’ hydroxyl acylation and primer extension followed by mutational profiling (SHAPE-MaP). SHAPE-MaP reactivity profiles were generated revealing the structure of splicing and cryptic polyadenylation signal (PAS) elements within the targeted region. We identified enhancer binding motifs surrounding the 5’ splice site and hidden elements of the cryptic PAS. Based on these structural profiles, we generated RNA therapies to unravel the hidden PAS to activate expression of the short therapeutic isoform.
EXTH-48. BMP4 BINDING PEPTIDE AMPHIPHILE NANOFIBERS FOR THE TREATMENT OF PEDIATRIC HIGH-GRADE GLIOMAS
Authors: Smith Cara , Nayak Sonali , Mahenthiran Ashorne , Wang Yufen , Fyrner Timmy , McClendon Mark , Mania-Farnell Barbara , Kessler John , Tomita Tadanori , James Charles , Stupp Samuel , XI Guifa 
Published: December 2020

Abstract
Pediatric high-grade glioma (pHGG) is among the most formidable cancers occurring in childhood. Bone morphogenetic protein 4 (BMP4) reduces the number of glioma stem-like cells and induces apoptosis. Treating tumors with exogenous BMP4 could prove effective in treating gliomas. However, a short half-life limits its clinical application. Glycosylated peptide amphiphile (GlycoPA), with a design inspired by heparin’s natural ability to bind growth factors including BMP4 through non-covalent interactions, was previously characterized and found to form high-aspect ratio supramolecular nanofibers that present growth-factor binding sulfated monosaccharides on their surface. These supramolecular nanofibers could carry excessive amounts of growth factor and markedly enhance their biological function. In this study, we verified that GlycoPA is able to bind BMP4 and dramatically increase its half-life with an ELISA assay. We also show that GlycoPA-BMP4, in comparison to free BMP4, significantly decreases pHGG cells’ proliferation in vitro. Initial in vivo intracranial distribution experimental results showed that GlycoPA has a superior normal brain distribution in comparison to a control PA (E2 PA) that has the same base structure as GlycoPA except with no glycosylated group. Preliminary results show that GlycoPA-BMP4 markedly decreases pediatric glioma tumor growth in comparison to free BMP4. Our combined in vitro and in vivo results demonstrate PA supramolecular nanofibers as an innovative and promising BMP4 delivery platform for clinical application in the treatment of brain tumors. Our future directions will investigate the therapeutic efficacy of GlycoPA-BMP4 in pediatric HGG through testing large numbers of animals and introducing first-line clinical chemotherapy drugs in combination and in various consequence.
EXTH-51. ANTI-INVASIVE EFFICACY AND SURVIVAL BENEFIT OF THE YAP-TEAD INHIBITOR VERTEPORFIN IN PRECLINICAL GLIOBLASTOMA MODELS
Authors: Barrette Anne Marie , Bouras Alexandros , Nudelman German , Mussa Zarmeen , Zaslavsky Elena , Hadjipanayis Constantinos , Birtwistle Marc , Tsankova Nadejda 
Published: December 2020

Abstract
Glioblastoma (GBM) remains an incurable disease, in large part due to its malignant infiltrative spread, and current clinical therapy fails to target the invasive nature of tumor cells in disease progression and recurrence. Here, we use the YAP-TEAD inhibitor Verteporfin to target a convergence point for regulating tumor invasion/metastasis and establish the robust anti-invasive therapeutic efficacy of this FDA-approved drug and its survival benefit across several preclinical glioma models. Using patient-derived GBM cells and orthotopic xenograft models (PDX), we show that Verteporfin treatment disrupts YAP/TAZ-TEAD activity and processes related to cell adhesion, migration and epithelial-mesenchymal transition. In-vitro, Verteporfin impairs tumor migration, invasion and motility dynamics. In-vivo, intraperitoneal administration of Verteporfin in mice with orthotopic PDX tumors shows consistent drug accumulation within the brain and decreased infiltrative tumor burden, across three independent experiments. Interestingly, PDX tumors with impaired invasion after Verteporfin treatment downregulate CDH2 and ITGB1 adhesion protein levels within the tumor microenvironment. Finally, Verteporfin treatment confers survival benefit in two independent PDX models: as monotherapy in de-novo GBM and in combination with standard-of-care chemoradiation in recurrent GBM. These findings indicate potential therapeutic value of this FDA-approved drug if repurposed for GBM patients.
EXTH-59. POTENT, SELECTIVE, AND BRAIN PENETRANT INHIBITORS OF EXTRACELLULAR DOMAIN EGFR ONCOGENIC MUTANTS EXPRESSED IN GBM DEMONSTRATE EFFICACY IN AN INTRACRANIAL PATIENT DERIVED XENOGRAFT MODEL
Authors: O’Connor Matthew , Lucas Matt , Romashko Darlene , Rasmussen Sara , Fiorenza Raffaele , Lin Tai-An , Waters Nigel , Trainor George , Flohr Alexander , Ottaviani Giorgio , Roberts Christopher , Buck Elizabeth , Nicolaides Theodore , Raleigh David , Ozawa Tomoko , Arista Luca 
Published: December 2020

Abstract
EGFR mutations identified in glioblastomas (GBM) occur nearly exclusively at the allosteric extracellular domain (ECD) and constitutively activate oncogenic signaling. Despite wide success in treating tumors expressing EGFR catalytic site mutants, no drug has demonstrated clinical utility against tumors expressing the extracellular domain EGFR mutants. We demonstrate that the family of ECD mutations are not only co-expressed in GBM, but that they all activate the oncogene through a similar disulfide bond-mediated receptor dimerization mechanism. This dimerization occurs independent of ligands and renders the Locked-dimer (LoDi)-EGFR insensitive to agents that target the EGFR kinase domain mutants in NSCLC. The kinase conformation induced by these ECD mutations seen in glioblastomas is both oncogenic and altered from kinase domain mutations, thus necessitating a new approach to targeting. By screening against cells expressing LoDi-EGFR mutants, we have identified the first inhibitors that potently and selectively target LoDi-EGFR mutants versus both canonical active site oncogenic mutants and wild type EGFR. Through an optimization effort, we have identified a novel family of potent and selective LoDi-EGFR mutant inhibitors that effectively penetrate the blood brain barrier (BBB) following oral dosing in preclinical studies. A leading exemplar, BDTX-GBM-001, inhibits the 5 major LoDi-EGFR mutants expressed in GBM with antiproliferative potency of ~10 nM while showing favorable selectivity versus the human kinome. When dosed orally in the intracranial GBM6 patient derived xenograft model at 50, 30, and 15 mg/kg, a dose responsive decrease in tumor growth, as well as a statistically significant increase in survival, were observed. These data support the continued evaluation of rationally designed BBB penetrant inhibitors selectively targeting the common LoDi-EGFR mutants and enable the first chance to fully test the clinical hypothesis of EGFR driver mutants in GBM.
EXTH-61. COMBINATION OF DISULFIRAM AND COPPER INDUCES NPL4 AGGREGATION, TARGETS CD133-NESTIN CELLS AND EXTENDS SURVIVAL IN MEDULLOBLASTOMA GROUP 3 MODELS
Authors: Serra Riccardo , Zhao Tianna , Huq Sakibul , Gorelick Noah , Casaos Joshua , Cecia Arba , Mangraviti Antonella , Olivi Alessandro , Brem Henry , Jackson Eric M , Tyler Betty 
Published: December 2020

Abstract

BACKGROUND
Medulloblastoma (MB), the most common brain malignancy among children, is classified into four molecular subtypes, WNT-driven, Shh-driven, Group 3 and 4. The aim of this study was to assess the effects of the combination of Disulfiram, an inhibitor of Aldehyde Dehydrogenase, and Copper in Shh-driven and Group 3 MB, in vitro and in vivo.

METHODS
The mechanisms of action and anti-cancer stem-cell effects of disulfiram were evaluated with clonogenic assays, flow-cytometry (FC), western blotting (WB), and immunofluorescence (IF) using established MB cell-lines - ONS76, UW228, D425med, D341 and D283- representing the main molecular subtypes. Survival, tumor volume, nuclear protein localization protein-4-expression (NPL4) and markers of proliferation/apoptosis were assessed in multiple models of Group 3 MB in vivo and ex vivo with WB and immunohistochemistry (IHC).

RESULTS
Significant in vitro cytotoxicity was demonstrated at nanomolar concentrations of DSF in all lines. DSF/Cu++ induced cell death (increased AnnV/PI, cleaved-Poly(ADP-ribose)polymerase fraction, and Apoptosis Inducing Factor on WB/FC/IF, in vitro and ex vivo) through NPL4 accumulation in cell nucleus and intracellular buildup of poly-ubiquitylated proteins. DNA damage was also detected with WB and H2AX foci on immunofluorescence. Flow-cytometry analysis demonstrated a significant reduction in ALDH, Nestin- and CD133-positive cells in Group 3 lines, confirmed with WB in vitro and ex vivo. DSF/Cu++-toxicity was tested in vivo in multiple dose-escalating trials, and the combination significantly prolonged survival and reduced tumor volume in D425 and D341 xenografts. IHC showed lower Ki67 and increased Cleaved-Caspase-3 expression, higher NPL4-positive cells and no difference in NeuN and GFAP-positive cells after treatment.

CONCLUSIONS
DSF/Cu++ demonstrated a potent therapeutic effect on Shh-driven and Group 3 MB cell lines by determining apoptosis, targeting cancer stem cells and inducing DNA damage. Our data suggest that this combination may serve as a novel treatment, alone or with existing therapies, for pediatric MB.
EXTH-71. CYTOSTATIC HYPOTHERMIA FOR GLIOBLASTOMA
Authors: Faaiz Enam Syed , Huang Jianxi , Kilic Cem , Tribble Connor , Betancur Martha , Blocker Stephanie , Owen Steven , Bellamkonda Ravi 
Published: December 2020

Abstract
As a cancer therapy, hypothermia has been used at sub-zero temperatures to cryosurgically ablate tumors. However, these temperatures can indiscriminately damage both tumorous and healthy cells. Additionally, strategies designed to kill tumor typically accelerate their evolution and recurrence can be inevitable in cancers such as glioblastoma (GBM). To bypass these limitations, here we studied the use of hypothermia as a cytostatic tool against cancer and deployed it against an aggressive rodent model of GBM. To identify the minimal dosage of ‘cytostatic hypothermia’, we cultured at least 4 GBM lines at 4 continuous or intermittent degrees of hypothermia and evaluated their growth rates through a custom imaging-based assay. This revealed cell-specific sensitivities to hypothermia. Subsequently, we examined the effects of cytostatic hypothermia on these cells by a cursory study of their cell-cycle, energy metabolism, and protein synthesis. Next, we investigated the use of cytostatic hypothermia as an adjuvant to chemotherapy and CAR T immunotherapy. Our studies demonstrated that cytostatic hypothermia did not interfere with Temozolomide in vitro and may have been synergistic against at least 1 GBM line. Interestingly, we also demonstrated that CAR T immunotherapy can function under cytostatic hypothermia. To assess the efficacy of hypothermia in vivo, we report the design of an implantable device to focally administer cytostatic hypothermia in an aggressive rodent model of F98 GBM. Cytostatic hypothermia significantly doubled the median survival of tumor-bearing rats with no obvious signs of distress. The absence of gross behavioral alterations is in concurrence with literature suggesting the brain is naturally resilient to focal hypothermia. Based on these findings, we anticipate that focally administered cytostatic hypothermia alone has the potential to delay tumor recurrence or increase progression-free survival in patients. Additionally, it could also provide more time to evaluate concomitant, curative cytotoxic treatments.