bluuebunny/crossref_metadata_2025_split huggingface dataset:
SCIDOT-20. ADAPTING ENGINEERED CELL THERAPIES TO UNDERSTAND AND OVERCOME GLIOBLASTOMA RESISTANCE USING INTEGRATED IN VIVO AND EX VIVO MODELS
Authors: Satterlee Andrew , Dunn Denise , Floyd Scott , Hingtgen Shawn 
Published: November 2019

Abstract
Genetically engineered neural stem cells (NSCs) are a promising therapy for the highly aggressive brain cancer glioblastoma (GBM), yet treatment durability remains a major challenge. We sought to define the events that contribute to dynamic adaption of GBM during NSC treatment and develop strategies to convert initial tumor kill into sustained GBM suppression. Using a unique hybrid tumor model treated with human skin-derived induced NSCs (iNSCs) releasing the pro-apoptotic agent TRAIL, we investigated how spatial distribution of tumor and iNSCs affects GBM adaption throughout recurrence. Serial bioluminescent imaging (BLI) was used to track tumor volumes in vivo, while a subset of mice were sacrificed 6, 13, and 20 days post-treatment to harvest brains and generate living ex vivo tissue slices. Live animal imaging showed iNSC-TRAIL treatment rapidly decreased tumor volumes when delivered into the primary tumor mass; however, minimal impact on tumor growth was observed when cells were delivered into distal regions of the brain. In contrast, high-resolution imaging of living brain sections showed extensive impacts of iNSC-TRAIL therapy that could not be visualized with BLI. The living slices showed iNSC-TRAIL treatment into the primary tumor decreased the solid, but not the invasive, tumor burden. Treatment into the lateral ventricles did impact tumor kill and was more effective at treating the invasive tumor burden and maintaining inhibition than treatment into the contralateral parenchyma. We next utilized the living tissue slices to explore the sensitivity of the recurrent tumors to TRAIL. When therapy was applied to slices harboring recurrent tumor, treatment again significantly reduced tumor volumes, suggesting tumors had not acquired TRAIL resistance. These results informed an additional in vivo survival study and subsequent PCR analysis of untreated and recurrent tumors, and combine the fidelity of in vivo studies with the speed and spatial resolution of living brain slice technology.
ANGI-05. ORIGIN OF MICROVASCULAR PROLIFERATION IN PILOCYTIC ASTROCYTOMA - MVP IN PILOCYTIC ASTROCYTOMA MIGHT PARTIALLY COMPRISE TUMOR-DERIVED CELLS
Authors: Yamashita Shinji , Takeshima Hideo , Watanabe Takashi , Yokogami Kiyotaka 
Published: November 2019

Abstract
Microvascular proliferation (MVP), an aberrant vascular structure containing multilayered mitotically active endothelial- and smooth-muscle cells/pericytes, is a histopathological hallmark of glioblastoma multiforme (GBM). Although MVP tends to be associated with high-grade glioma, it has also been detected in WHO grade I pilocytic astrocytoma (PA). However, little is known about the mechanism underlying its formation. Using TP53 point mutations as a marker for tumor-derived cells, we earlier reported that MVP was partially converted from tumor cells via mesenchymal transition. In the current study we used the KIAA1549-BRAF fusion gene as a marker to assess whether MVP in PA contained tumor-derived cells. cDNA synthesized from frozen tissue of six PA patients operated at our institute was analyzed to detect the KIAA1549-BRAF fusion gene by reverse transcription polymerase chain reaction (RT-PCR) assay. The breakpoint in the fusion gene was characterized by long and accurate PCR (LA-PCR) and Sanger sequencing of genomic DNA. Distinct tumor cells and cellular components of MVP were obtained by laser microdissection. For the qualitative and quantitative detection of the KIAA1549-BRAF fusion gene we performed genomic and digital PCR assays. Fluorescence in situ hybridization (FISH) was used to assess gene fusion in cellular components of MVP. Samples from three PA patients harbored the KIAA1549 exon 15, BRAF exon 9 fusion gene. In two patient samples with abundant MVP, RT-PCR assay detected strong bands arising from the KIAA1549-BRAF fusion gene in both tumor cells and cellular components of MVP. Digital PCR showed that vis-à-vis tumor tissue, its relative expression in cellular components of MVP was 42% in one- and 76% in another sample. FISH revealed amplified signals in both tumor cells and cellular components of MVP indicative of tandem duplication. Our findings suggest that in patients with PA, some cellular components of MVP may be tumor-derived.
SCIDOT-26. THE ROLE OF TUMOR-DERIVED GRANULOCYTE MACROPHAGE COLONY STIMULATING FACTOR (GM-CSF/CSF2) IN REGULATION OF MICROGLIA-DEPENDENT INVASION IN GLIOMAS
Authors: Poleszak Katarzyna , Pasierbinska Maria , Ellert-Miklaszewska Aleksandra , Wojtas Bartosz , Wojnicki Kamil , Kaminska Bozena 
Published: November 2019

Abstract
Brain resident immune cells (microglia) and peripheral macrophages accumulate in malignant gliomas and constitute for 30–50% of the tumor mass. These immune cells are polarized by factors released by glioma and become the pro-invasive, immunosuppressive cells that support tumor progression. We have previously found that tumor-derived granulocyte macrophage colony stimulating factor (GM-CSF/Csf-2) is a crucial factor controlling accumulation of microglia and macrophages in murine gliomas. The analysis of TCGA dataset revealed overexpression of the CSF2 gene (encoding GM-CSF) in a set of mesenchymal glioblastomas (most aggressive WHO grade IV gliomas) and its association with high immune gene expression. To study the role of GM-CSF in microglia-stimulated glioma invasion, we used a co-culture system, which mimics microglia interactions with tumor cells. We silenced the expression of CSF2 in glioma cells and found reduced microglia-dependent invasion of glioma cells. To translate those results into clinically relevant setting, we designed and tested humanized short peptides interfering with binding of GM-CSF to its receptor. Selected peptide effectively inhibited binding of GM-CSF to its receptor as demonstrated with different methods. We selected the non-cytotoxic peptides that potently blocked microglia-dependent glioma invasion in cell co-cultures. Blocking GM-CSF-receptor signaling pathway with a neutralizing antibody against a GM-CSF receptor also inhibited microglia-dependent invasion of glioma cells. Altogether, our results demonstrate that glioma-derived GM-CSF supports pro-tumorigenic polarization of microglia turning them into cells that facilitate glioma growth and shape the immune microenvironment. The study was supported by grant 2014/15/B/NZ3/04704 from The National Science Centre, Poland.
SCIDOT-32. NEUROSURGICAL DELIVERY OF THE POLY ADP RIBOSE POLYMERASE-1 INHIBITOR OLAPARIB FROM A THERMO-RESPONSIVE BIODEGRADABLE PASTE POTENTIATES RADIOTHERAPY AND PROLONGS SURVIVAL IN HIGH-GRADE GLIOMA
Authors: Smith Stuart , Serra Riccardo , Rowlinson Jonathan , Gorelick Noah , Veal Gareth , Shakesheff Kevin , Brem Henry , Grundy Richard , Tyler Betty , Rahman Ruman 
Published: November 2019

Abstract
There has been considerable interest in repurposing the poly ADP ribose polymerase inhibitor and purported radiosensitiser olaparib (Lynparza), with a recent dose escalation study of olaparib plus temozolomide in recurrent GBM showing good tolerance (Fulton et al 2018). Due to systemic therapy-associated caveats such as dose-limiting toxicities and blood-brain-barrier penetration, here we assess localised post-surgical delivery of olaparib from our previously developed poly(DL-lactic-co-glycolic acid) (PLGA) and poly(ethylene glycol) (PEG) (PLGA/PEG) thermo-sensitive biodegradable paste. Metabolic and clonogenic assays revealed impaired proliferation and clonal growth respectively, upon acute exposure of high-grade glioma cells to olaparib (3–5µM), an effect dramatically potentiated with 3Gy radiation. Flow cytometry of Annexin V+/Propidium iodide+ rodent and human high-grade glioma cells, revealed a significant cell proportion increase at late stage apoptosis when exposed to 2–3µM olaparib and 3Gy radiation (relative to untreated, olaparib alone or radiation alone). A high-grade glioma orthotopic allograft study is ongoing where we already observe a significant overall survival benefit of locally-delivered 10% and 20% w/w (drug:polymer ratio) olaparib via PLGA/PEG paste post-surgery with adjuvant radiotherapy, compared to surgery/oral temozolomide/radiotherapy (GBM standard-of-care) and surgery/systemic olaparib (120 days vs. 44 vs 30 respectively). A more pronounced survival benefit, as determined by the total number of long-term surviving animals, was observed with combined PLGA/PEG/olaparib/temozolomide/radiotherapy or PLGA/PEG/olaparib/etoposide/radiotherapy. RNAseq data from 10 GBM patients show significantly elevated levels of apoptosis-inducing factor-1 in 5-aminolevulinic acid (5ALA)+ fluorescence–activated cell sorted populations (i.e. purified tumour cells from the invasive margin), relative to 5ALA- cells, confirming PARP-1 activity in infiltrative tumour cells. Collectively our data supports a clinical rationale for localised olaparib delivery with adjuvant radiotherapy.
SCIDOT-34. BRAIN INJURY SIGNALS SYSTEMIC IMMUNOSUPPRESSION THROUGH THYMIC INVOLUTION
Authors: Ayasoufi Katayoun , K Pfaller Christian , H Khadka Roman , Jin Fang , Zheng Jiaying , R Schuelke Matthew , Evgin Laura , J Hansen Michael , T Himes Benjamin , E Fain Cori , P Tritz Zachariah , N Goddery Emma , T Yokanovich Lila , R Pease Larry , G Vile Richard , J Johnson Aaron 
Published: November 2019

Abstract
Systemic immunosuppression following neurological insults including stroke, traumatic brain injury, and glioblastoma (GBM) causes mortality and leads to failure of immune-modulating therapies. Exact immunological nature and the underlying mechanisms of this immunosuppression are unknown. Our goal was to define effects of neurological insults given exclusively to the brain on the thymus. The thymus is the primary immune organ responsible for T-cell development and maintenance both in children and in adults. We evaluated the brain-thymus communication using the following neurological insults: physical injury, CNS viral infection, sterile injury, tumor implantation, and seizures. All insults resulted in significant thymic involution that was reversible upon clearance of the insult. Thymic involution did not occur following similar peripheral insults. We next demonstrated that the GL261 model of GBM recapitulates hallmark features of peripheral immunosuppression observed in GBM patients including low CD4 T-cell counts. Thus, we aimed to further study the immunosuppression affecting the thymus in this clinically relevant model. Principle component analysis following RNA-sequencing of thymi from naïve and glioma-bearing mice revealed unbiased separation of the groups suggesting that the thymus is directly affected by a brain tumor. To determine the extent to which thymic involution was caused by a soluble factor we employed parabiosis. We demonstrated that thymic involution was transferable from glioma-bearing to non-tumor-bearing parabionts. Similarly, serum taken from GL261 glioma-bearing mice potently inhibited proliferation of T-cells in vitro. Together our data demonstrate that CNS-specific insults, regardless of nature, cause immunosuppression by prompting thymic involution through circulating factors. This accounts at least partially for immune deficiencies observed following neurological injuries. Identification of this suppressive factor is crucial in designing future therapeutics for GBM patients, and patients with other acute and chronic neurological trauma.
SCIDOT-36. PREDICTIVE CED INFUSION VOLUMES FOR SURGICAL PLANNING AND INFUSION REGIME STRATEGIES
Authors: Killick-Cole Clare , Woolley Max , Johnson David , Lewis Owen , Skinner Paul , Bienemann Alison , Gill Steven 
Published: November 2019

Abstract
Previous research and clinical trials have highlighted the utility of convection-enhanced delivery (CED) to directly administer therapeutics to the brain. This method bypasses the blood-brain barrier, which is a major obstacle in systemic drug delivery. The Renishaw Neuroinfuse™ recessed step catheter has been developed to utilise a mechanism we have termed “controlled reflux” to maximise distribution within brain targets, whereby the infusate tracks to a flow inhibiting feature. Once in contact with this feature, the flow pathway is initiated radially along the step region, facilitating a low-pressure infusion profile that minimises fast flow-rate tissue damage at the catheter tip whilst maximising coverage. This can be demonstrated through in vitro studies, in vivo preclinical work and humanitarian cases treating DIPG. The controlled reflux mechanism provides a level of infusion prediction, which can be used for catheter placement planning in order to optimize infusion distribution within a chosen target area. The Neuroinfuse™ catheter is delivered through an implantable guide tube whereby the guide tube and the catheter lengths are cut to provide bespoke features within the controlled reflux zone. By manipulating catheter step lengths this way, catheters can be designed to achieve target distribution volumes within an individual’s unique brain anatomy. Here we will present data demonstrating the utility of the acute catheter system, and its additional use as a modular component of the chronic drug delivery system. This modularisation strategy provides attributes for catheter placement and infusion distribution planning that spans across multiple indications for neuro-oncology and neurodegenerative diseases.
SCIDOT-41. NANOTHERAPEUTIC TARGETING OF TUMOR ENDOTHELIUM FOR ENHANCING DRUG DELIVERY PAST THE BLOOD-BRAIN BARRIER
Authors: Kiguchi Hiroto , Manzari Mandana , Vaynshteyn Jake , Gerwin Jeffrey , Tylawsky Daniel , Li Na , Shah Janki , Shamay Yosi , Greenblatt Matthew , Heller Daniel , Praveen Raju G 
Published: November 2019

Abstract

OBJECTIVE
The Sonic Hedgehog (SHH) medulloblastoma subgroup accounts for ~25% of all cases and has an intermediate prognosis. Current conventional therapies result in devastating morbidities including intellectual disability and secondary malignancies. Although molecularly targeted agents that inhibit the SHH pathway have demonstrated clinical efficacy, recent studies have shown on-target secondary toxicities on bone development suggesting new therapeutic approaches are needed.

METHODS
We investigated the efficacy of the SHH pathway inhibitor, Vismodegib packaged in a fucoidan-based nanoparticle (Fi-Vis) that targets P-selectin, a protein overexpressed on vascular endothelial cells and induced by low-dose ionizing radiation (XRT) in a time- and dose-dependent manner. This P-selectin targeting nanoparticle drug delivery system shows selectivity toward tumor vasculature and not normal brain vasculature in a genetic SHH medulloblastoma mouse model as assessed by ex vivo infrared imaging and two-photon intravital imaging.

RESULTS
Quantitative RT-PCR analysis of SHH medulloblastoma tissue following single dose XRT and Fi-Vis treatment (10mg/kg) showed a synergistic inhibition of Gli1 expression (>90% target inhibition). Furthermore, we demonstrate that very low dose XRT (0.25Gy) can induce P-selectin expression specifically within MB tumor vasculature and synergize with low dose Fi-Vis (10mg/kg) to significantly enhance mouse survival (p<0.01) when compared to radiation or Fi-Vis alone. Furthermore, assessment of bone toxicity using micro-CT and histological analysis following Fi-Vis administration in postnatal (P10) mice shows no bone toxicity when compared to free Vismodegib. Finally, in vitro studies using mouse brain endothelial cells suggest at least in part a caveolin-1 mediated transcytosis mechanism of crossing the endothelial blood-brain barrier.

CONCLUSIONS
These data suggest applicability of combined XRT and tumor vasculature-targeted nanotherapeutic dose de-escalation strategies for SHH medulloblastoma with implications for other pediatric and adult brain tumors.
SCIDOT-42. FT-2102 – A POTENT AND SELECTIVE BRAIN PENETRANT INHIBITOR OF MUTANT ISOCITRATE DEHYDROGENASE
Authors: Ribadeneira Maria , Guichard Sylvie , Yao Lili , Toms Angela , Forsyth Sanjeev , Thomson Blythe , Ehrlich Paul 
Published: November 2019

Abstract

BACKGROUND
Iocitrate dehydrogenase mutations (mIDH1) are present in >70% of patients with Grade II/III gliomas resulting in production and accumulation of (R)-2-hydroxyglutarate (2-HG) causing DNA hypermethylation and promoting tumorigenesis. This abstract summarizes the structure-based design of FT-2102, a potent and selective inhibitor of mutated IDH1-R132 with brain distribution (Kpuu) that is in context of minimal effective concentrations required in brain to modulate 2-HG.

METHODS
The crystal structure of mutated IDH1 in complex with FT-2102 and NADPH cofactor (2.1A resolution) was determined via sitting-drop vapour-diffusion set-ups. HCT116/IDH1 R132H were implanted in Balb/c nude mice and FT-2102 was administered orally twice daily. FT-2102 and 2-HG levels in plasma and xenografts were determined by LC/MS. In silico and in vitro models were used to determine the extent of brain distribution and ex-vivo rat data was generated to validate the projected distribution into brain tissue (Kpuu).

RESULTS
In tumor Xenograft (HCT116/IDH1-R132H), FT-2102 inhibits tumor 2-HG production with an IC50 of 24nM which is consistent with its in vitro IC50 of 18nM. FT-2102 unbound plasma concentrations of 256nM in xenografted mice were found to achieve 90% reduction of 2-HG in tumor. Rat data showed that FT-2102 partitions into brain with a Kpuu of 0.45. Based on these data, the concentration of FT-2102 in brain to significantly reduce 2HG is predicted to be 115nM. Recent publications (Natsume, et al, ASCO19) propose 90% reduction of 2-HG (90%) is associated with tumor reduction in the brain.

CONCLUSION
The structure-based design of FT-2102 has facilitated CNS penetration in animal models and is undergoing evaluation in ongoing clinical trials including patients with CNS based IDH1m tumors (NCT: 03684811).
ANGI-07. NOVEL FUSION GENE PTPRZ1-MET PROMOTES GLIOMAS ANGIOGENESIS BY UP-REGULATING EXOCRINE PROTEIN IGF2BP3
Authors: Liu Yanwei , Qiu Xiaoguang , Jiang Tao 
Published: November 2019

Abstract
We previously reported a novel fusion gene PTPRZ1-MET in 15% of secondary GBM (sGBM). Subsequent studies showed that ZM fusion indicates a significantly worse prognosis and promotes glioma progression by increasing MET activity. We have demonstrated hyper-activation of MAPK and STAT3 signaling and elevated angiogenesis activities in patients and subcutaneous tumors with ZM fusion. However, the angiogenesis mechanism regulated by ZM is still unclear. In this study, 66 up-regulated and 66 down-regulated genes were identified on 8 sGBMs with ZM fusion comparing gene expression with 135 negative sGBMs (fold-change >2.5 & p.value < 0.05). ZM-harboring U87 MG xenograft models were conducted and RNA sequencing was performed in 3 subcutaneous tumors with ZM-harboring U87 MG and 3 negative control. 384 up-regulated and 698 down-regulated genes were identified on 3 ZM-harboring samples comparing gene expression with 3 negative control samples (fold-change >2.5 & p.value < 0.05. Three subcutaneous tumors with ZM-harboring U87 MG were treated by a MET kinase inhibitor, PLB-1001. Finally, the expression of 13 up-regulated gene decreased and 10 down-regulated genes increased after treatment by PLB-1001. We overlapped the candidate genes between patient samples and subcutaneous tumors and 5 up-regulated and 4 down-regulated genes was appeared and most associated with ZM fusion. Prognostic analysis of 9 candidate genes on sGBM revealed that a higher expression of IGF2BP3 indicates a worse prognosis. In further study, we found that IGF2BP3 can be secreted out of the gliomas stem cells (GSCs) and promote proliferation of vascular endothelial cells and the expression of CD31. IGF2BP3 siRNA can block this pathway and inhibit the angiogenesis. Conclusion, our study demonstrated a new pathway promoting angiogenesis in gliomas. But the regulating mechanism between ZM fusion gene and IGF2BP3 deserves to do further research.
SCIDOT-44. CREATING CAUSAL CAPABILITIES IN FUNCTIONAL BRAIN MAPPING USING A CED APPROACH
Authors: Block Walter , Birns Rasmus , Olsen Miles , Hurley Samuel , Brodsky Ethan , Rajala Abigail , Filla Caitlynn , McMillan Alan , Alexander Andrew , Jenison Rick , Populin Luis 
Published: November 2019

Abstract

INTRODUCTION
The spatial and temporal resolution limits of functional MRI (fMRI) brain mapping provide primarily correlative information on brain connectivity. Determining how one region causally modulates and mediates activity in other regions remains difficult with fMRI. We demonstrate a simple means to add causality in resting state functional connectivity MRI (rs-fcMRI) using techniques developed first for convection-enhanced delivery (CED) of therapeutics. Here we use CED to guide and monitor pharmacologic alteration of a local brain region in anaesthetized Rhesus monkeys while monitoring rs-fcMRI signal changes.

METHODS
Pre-surgical MRI was used to determine skull locations for craniotomies for installation of NavigusTMbrain ports in two untrained monkeys slated for euthanasia. The ports were aligned in real–time to provide trajectories aimed at the central nucleus of the amygdala (CeA). Fused silica catheters were then inserted into the CeA where 24 mg of muscimol (inhibitory agent) was infused in 24 ml of buffered solution under pressure over 12 minutes, first on the right side and then on the left side. rs-fcMRI studies were done for 45 minutes before and after the unilateral infusion and then after the bilateral infusion.

RESULTS
Catheters were successfully aligned and inserted into the CeA targets with sub-mm accuracy. T2-weighted imaging detected the enhanced T2 from the infusion’s buffer. Pre-infusion rs-fcMRI provides results consistent with prior studies, which have shown that the CeA is most strongly connected to the contralateral CeA. This connectivity was significantly reduced following both unilateral and bilateral injections of muscimol into the CeA, demonstrating the effectiveness of the muscimol infusions. Conditional Grainger Causality (CGC) analysis shows unexpected new connectivity after the unilateral infusion. Upon the bilateral infusion, global effective connectivity in the region is reduced.

CONCLUSION
Expected and unexpected changes in resting state functional connectivity resulted from unilateral and bilateral infusions of inhibitory agents.