bluuebunny/crossref_metadata_2025_split huggingface dataset:
CBMT-18. THE ROLE OF BIOMARKER CANDIDATE GELSOLIN AND ITS MICRORNAS IN GLIOBLASTOMA
Authors: Nakada Mitsutoshi , Zhang Jiakang , Furuta Taskuya , Jiapaer Shabierjiang , Tamai Sho , Sabit Hemragul , Uchida Yasuo , Ohtsuki Sumio , Terasaki Tetsuya 
Published: November 2019

Abstract

BACKGROUND
Among potential glioblastoma (GBM) blood biomarkers that we identified recently, we focused on gelsolin (GSN), a key regulator of actin filament disassembly. GSN was significantly lower in the blood of patients with GBM than in that of healthy controls. In this study, we analyzed the function of GSN and identified microRNAs (miRs) involved in GSN expression in GBM.

METHODS
QRT-PCR and western blot were introduced to evaluate the expression level of GSN in normal brain and GBM tissue. The localization of GSN was examined by immunohistochemistry and immunocytochemistry using human samples. The association between the expression level of GSN and progression free survival (PFS) /overall survival (OS) in GBM was assessed by Kaplan-Meier analysis. The function of GSN and its signal transduction in glioma cell lines were analyzed using small interfering RNA (siRNA) knockdown of GSN. Additionally, miRs controlling GSN expression were retrieved from databases of miRs, and miRs related to GSN expression were identified in GBM tissues.

RESULTS
The expression level of GSN was significantly lower in GBM tissues compared to normal brains. Normal astrocytes mainly expressed GSN. High expressor of GSN showed longer PFS and OS than low expressor. Proliferation and invasion in glioma cell lines were significantly promoted by siRNA for GSN accompanied with the activation of glycogen synthase kinase 3β. In GBM tissues, the expression levels of GSN and miR-654-5p, 450b-5p showed an inverse correlation. The inhibitor for miR-654-5p and miR-450b-5p accelerated GSN expression resulting reduction of proliferation.

CONCLUSION
GSN plays a role as suppressor of proliferation and invasion in GBM. miR-654-5p and miR-450b-5p which control GSN expression can be targets against GBM.
CBMT-20. SINGLE-CELL TRANSCRIPTOMICS RESOLVES CELLULAR HETEROGENEITY AND ONCOGENIC NETWORKS DURING MALIGNANT TRANSFORMATION OF PERIPHERAL NERVE SHEATH TUMORS
Authors: Man Natalie Wu Lai , Zhang Feng , Tian Weidong , Lu Richard 
Published: November 2019

Abstract
Malignant peripheral nerve sheath tumors (MPNSTs) are highly aggressive Schwann cell (SC)-derived sarcomas with strong metastatic proclivity and resistance to radiation and chemotherapy. Molecular events driving SC-to-MPNST transformation are incompletely understood. MPNST are heterogeneous tumors with a distinct microenvironment that contributes to the establishment of a tumor niche. Cancer behaviors including initiation, progression, metastasis and relapse cannot be fully defined by genetic mutations alone, but are critically dependent on intercellular communication between tumor cells and the microenvironment. However, currently, a comprehensive understanding of tumor cell lineage evolution, heterogeneity and cell-cell communication network in MPNST is lacking. A better understanding of cellular heterogeneity and tumor-initiating cells during tumorigenesis at a single-cell level will facilitate identifying molecular and cellular determinants underlying malignant transformation in MPNST. We have established a murine model of aggressive peripheral nerve malignancy with HIPPO-TAZ/YAP activation (Lats1/2-def mice), which provides a unique opportunity for dissecting mechanisms of SC malignant transformation. To identify potential PNST-driven progenitor populations, we compare single-cell transcriptome profiles of Lats1/2-def sciatic nerve tumors during pre-neoplastic and advanced stages. Our data reveal that early sciatic nerve tumors contain primarily mature SCs, whereas full-blown tumors harbor neoplastic SCs composed of different subsets: fast-proliferating, mesenchymal-like and neural crest stem cell-like cells, indicative of a developmental trajectory from differentiated SCs to tumor-like SCs with distinct molecular and transcriptional signatures. Interestingly, transformed SCs exhibit inflammation gene signature, which may suggest cell-autonomous inflammation-driven reprogramming that drives tumorigenesis. To characterize cellular heterogeneity in MPNST-like tumors, we further identify cell-cell communication networks between SC-derived tumor cells and cancer-associated stromal cells within the tumor microenvironment. In summary, our studies using single-cell transcriptomics in clinically relevant mouse models of PNST reveal tumor cellular heterogeneity and the microenvironment niche for driving SC tumorigenesis. It will provide principles for identifying potential targets or treatment strategies to cure MPNST.
CBMT-36. INITIAL EXPERIENCE WITH HYPERPOLARIZED [2-13C]PYRUVATE MR IMAGING IN PATIENTS WITH IDH-MUTANT GLIOMA
Authors: Autry Adam , Chung Brian , Chen Hsin-Yu , Gordon Jeremy , Lafontaine Marisa , Chang Susan , Villanueva-Meyer Javier , Larson Peder , Vigneron Daniel , Li Yan 
Published: November 2019

Abstract

INTRODUCTION
Hyperpolarized (HP) carbon-13 MR imaging allows for real-time non-invasive measurement of metabolism. Using HP [2-13C]pyruvate as a molecular probe enables the measurement of both aerobic glycolysis ([2-13C]lactate) and oxidative metabolism (such as [5-13C]glutamate and [5-13C]glutamine). This study presents the initial patient experience of acquiring HP [2-13C]pyruvate MR spectroscopic data.

METHODS
Two patients who presented with IDH-mutant gliomas (43 year-old male, grade II astrocytoma, RT/TMZ; 33 year-old female, grade III oligodendroglioma, no RT/TMZ) considered radiologically stable post resection were imaged using a 2D chemical shift imaging (CSI) sequence (15.6–18.8cm3 spatial resolution, 20s acquisition), following injection of 0.43mL/kg of 250mM HP [2-13C]pyruvate. HP [2-13C]pyruvate, [5-13C]glutamate, [5-13C]glutamine, and [2-13C]lactate resonances were quantified within a lesion voxel and contralateral normal-appearing voxel. The proton images were aligned to HP data enabled quantification of apparent diffusion coefficients (ADC), perfusion peak height (PH), and MR spectroscopy choline-to-N-acetyl-aspartate indices (CNI). ADC (nADC) and PH (nPH) values were normalized by the median value in normal-appearing white matter.

RESULTS
Proton exams revealed no Gd-enhancement lesions. For the T2-hyperintense lesion (T2L), volumeT2L=18.4/4.2cc (Patient#1/Patient#2); median ADCT2L =1.86/1.64; max CNIT2L=3.2/6.5; 90th percentile nPHT2L =1.09/2.11. HP data displayed maximum signal-to-noise ratios (SNR) for [2-13C]pyruvate, [5-13C]glutamate, [5-13C]glutamine, and [2-13C]lactate of 1360, 44, 27, and 400, respectively. The HP CSI data contained 15.9/13.7 %T2L; 15.1/4.1 %NAWM; 15.7/22.0 %GM (Patient#1/Patient#2) in selected lesion voxels, while contralateral voxels had %NAWM:%GM of Lesions demonstrated a reduced HP glutamate/pyruvate ratio [#1: 0.0089/0.0102 (lesion/normal voxel); #2: 0.0170/0.0269] and an elevated HP glutamate-to-glutamine ratio in both patients [#1: 0.81/0.66; #2: 0.84/0.66].

DISCUSSION
This first patient experience with HP [2-13C]pyruvate showed adequate SNR for quantifying HP [2-13C]pyruvate, [5-13C]glutamate, [5-13C]glutamine, and [2-13C]lactate resonances. Future studies will optimize imaging protocols and expand the patient cohort to evaluate aberrant metabolism related to IDH-mutant tumor.
CBMT-40. THE RELATIONSHIP BETWEEN GLIOMA AND THE GUT-BRAIN AXIS
Authors: Patrizz Anthony , Zorofchain Soheil , Hines Gabriella , Takayasu Takeshi , Otani Yoshihiro , Swanner Jessica , Honarpisheh Pedram , Tandon Nitin , Putluri Vasanta , Putluri Nagireddy , Priya Ganesh Bhanu , Kaur Balveen , McCullough Louise , Ballester Leomar Y , Esquenazi Yoshua 
Published: November 2019

Abstract
Recent studies demonstrate the potential role of the microbiome in immune-oncology, revealing specific microbial taxa can augment the effects of various therapeutic modalities against tumors. Gut dysbiosis, a disequilibrium in the host’s bacterial ecosystem, can potentially lead to overrepresentation of some bacteria and favor chronic inflammation and immunosuppression. However, the effects of microbial dysbiosis on non-gastrointestinal cancers in particular gliomas are unknown. Here, we explored the effects of glioma and Temozolomide (TMZ) on the fecal microbiome (FM) in mice (n=24) and FM and metabolome in humans (n=40). Aged C57/B6 mice were implanted with Gl261 tumor cells or vehicle and were assigned to one of the following treatment (oral) groups: vehicle, 5mg/kg TMZ or 25mg/kg TMZ beginning 14 days after surgery for 3-weeks following a 5 day on/2 day off treatment. Fecal samples were collected prior to surgery, at treatment initiation and weekly thereafter until sacrifice and sequenced for 16s RNA. Fecal samples were collected from humans with newly diagnosed glioma before resection, chemoradiation, and after chemoradiation (16s RNA, metabolomic, neurotransmitter analysis). In mice, FM beta diversity was significantly altered with glioma (p=0.003) while the alpha diversity remained unchanged. At a genus and family level analysis the relative abundance of Bacteroides (p=0.01) and Bacteroidaceae (p=0.02) was increased. Beta diversity of mice receiving 5mg/kg TMZ changed from baseline (p=0.02). Collectively, this suggests that glioma alters the FM, to what consequence remains to be explored. Alpha (Observed OTUs, p=0.029) and beta diversity (p=0.034) differences in mice correlated with survival (< 25 - >25 days). In humans, norepinephrine and 5-hydroxyindoleacetic acid were significantly lower in glioma patients at diagnosis compared to controls. Our findings demonstrate for the first time the relationship between glioma and the gut-brain axis. Understanding alterations in the FM in glioma patients may allow novel interventions and should be further investigated.
CBMT-48. TARGETING METABOLIC REPROGRAMMING WITH NANOCURCUMIN IN GLIOBLASTOMA MULTIFORME
Authors: Suhail Hamid , Ramandeep Rattan , Shailendra Giri , deCarvalho Ana , Kalkanis Steven , Ali Meser 
Published: November 2019

Abstract
Glioblastoma (GBM) is a highly glycolytic aggressive brain tumor characterized by increased proliferation and resistance to chemotherapy and radiotherapy. AMPK has been reported as tumor suppressor and reprograms the cellular metabolic pathways and produces a metabolic checkpoint on the cell cycle though mTORC1, p53 and other modulators involved in cell proliferation, growth, survival and autophagy. The AMPK activity is diminished in gastric, breast and ovarian tumor cells by activated PI3K-AKT pathways. Cancer cells are able to reprogram their energy metabolism to compensate their high bioenergetic demands needed for their aggressive growth and survival. Curcumin exhibits pleiotropic properties and activate MAPK and leads to suppress p53, Wnt/β-catenin, SHH and PI3K-AKT signaling pathways. Curcumin or diferuloylmethane is a yellow polyphenol extracted from the rhizome of turmeric (Curcuma longa). The absorption, biodistribution, metabolism, and elimination studies of curcumin have, unfortunately, shown only poor absorption, rapid metabolism, and elimination of curcumin as major reasons for poor bioavailability of this interesting polyphenolic compound. We have engineered a curcumin-based nanoparticle (Curc-NP) which demonstrates high water solubility. Curc-NP was effectively transported into the cells by nanoparticles through endocytosis and localized around the nuclei in the cytoplasms. In vitro studies proved that the cytotoxicity of Curc-NP is more effective against U-251 cell line in a dose-dependent manner. Systemic delivery of Curc-NP led to preferentially accumulation in an orthotopic preclinical glioma model minimizing systemic toxic effect. Multicolor microscopy images of the tumor tissue showed that Curc-NP particles were internalized inside tumor cells selectively and localized within nuclei. Curc-NP demonstrated to restore the dysregulated AMPK activity in glioma cells. Curc-NP-induced AMPK activation resulted in inhibition of oncogenic signalling pathways in glioma. Curc-NP-induced metabolic reprograming in glioma cells will be examined and the in vivo therapeutic efficacy of Curc-NP in an experimental rat model of GBM will also be evaluated.
CSIG-07. TARGETING CELL POLARITY PROTEINS FROM THE SCRIBBLE COMPLEX DISRUPTS GLIOBLASTOMA STEM CELL VIABILITY AND INVASION IN NEURAL TISSUE
Authors: Kundu Somanath , Nandhu Mohan , Longo Sharon , Longo John , Richardson Timothy , Chin Lawrence , Viapiano Mariano 
Published: November 2019

Abstract
Despite their molecular heterogeneity, glioblastomas (GBMs) retain a common phenotypical feature, which is their diffuse invasion through neural tissue that makes complete resection impossible. This invasive ability requires changes in cell polarity for the tumor cells to migrate following cues from their microenvironment. Cytoskeleton-associated proteins of the DLG family are part of the Scribble polarity complex that maintains stable cell-cell junctions; accordingly, these proteins are “tumor suppressors” usually downregulated in solid tumors. However, we have found that one family member, DLG5, is highly upregulated in GBM compared to other solid tumors. Results from Western blot, immunohistochemistry, and RNAseq confirmed that DLG5 is highly expressed in GBM compared to normal brain and is the predominant DLG family member in GBM stem cells (GSCs). DLG5 knockdown reduced cell viability after four days in culture, but had an immediate (24h) negative effect on cell invasion through Matrigel and brain tissue. At the molecular level DLG5 knockdown downregulated components of the Sonic-Hedgehog pathway, including PTCH1 and Gli1, as well as SHH-regulated downstream genes (CCND2, cMYC and CD44). Accordingly, DLG5-deficient GSCs showed reduced Gli1 phosphorylation in response to exogenous SHH and lacked increased invasiveness in presence of SHH compared to control GSCs. Ongoing experiments are evaluating the growth and invasion of DLG5-deficient GSCs in response to signals derived from oligodendrocyte progenitor cells, which are a major source of SHH in the postnatal brain. Taken together, our results describe for the first time the expression of DLG proteins in malignant gliomas and reveal an unexpected pro-tumoral function for the protein DLG5 that differs from its proposed tumor-suppressor role in other solid cancers. Targeting DLG5 could disrupt the ability of GSCs to respond to signals enriched in the neural microenvironment (SHH), contributing to the long-term control of residual tumor after surgical resection.
CSIG-08. EXTRACELLULAR DOMAIN MUTATIONS IN EGFR RESULT IN A HYPERSENSITIVE RECEPTOR
Authors: French Pim , de Wit Maurice , de Heer Iris , van Royen Martin , Vallentgoed Wies , Hoogstrate youri , Sillevis Smitt Peter 
Published: November 2019

Abstract

INTRODUCTION
The Epidermal Growth Factor Receptor (EGFR) is a driver gene that is amplified in more than half of all glioblastomas. After the initial high copy-number amplification, secondary missense mutations in the extracellular, ligand binding domain of EGFR can evolve. We here performed analysis on these mutations to better understand their function.

METHODS
Activation of EGFR-mutation constructs was measured by western blot and high-throughput quantitative image analysis using EGFR and phospho-EGFR specific antibodies.

RESULTS
Amphiregulin (AREG) is a low affinity EGFR ligand and was able to only marginally activate EGFRwt at high concentrations. In contrast however, AREG strongly activated all extracellular domain (ECD) mutation constructs (R108K, A289V and G598V). As expected, EGF-stimulation resulted in a strong activation in both EGFRwt and ECD mutation constructs. Further dose response analysis showed that in EGFRwt, all high affinity EGFR ligands (EGF, TGFa, HB-EGF and BTC) resulted in a strong activation and all low affinity ligands AREG, EREG and EPGN resulted in a markedly weaker activation. All ECD mutations however, showed strong activation towards all EGFR ligands, including the low affinity ligands (40%-80% of EGF stimulation). The constitutively active, ligand independent EGFRvIII mutation did not respond to any of the ligands and was mainly found to have an intracellular localization. Interestingly, the presence of ECD mutations and EGFRvIII are inversely correlated: in three large datasets (TCGA, Belob and Intellance 2), the majority of samples expressing EGFRvIII do not express additional ECD mutations and vice versa. ECD mutations likely affect stability of the tethered, inactive conformation thereby increasing exposure of the dimerization domain (II), resulting in increased ligand-sensitivity.

CONCLUSION
These experiments show that EGFR containing extracellular missense mutations render the receptor more sensitive to stimulation by low affinity ligands. Glioblastomas evolve to either become independent of ligand (EGFRvIII) or become ligand-hypersensitive (ECD mutations).
CSIG-12. PREX1 LINKS ABERRANT PI 3-KINASE PATHWAY SIGNALING TO MAINTENANCE OF THE NEURAL STEM CELL-LIKE PHENOTYPE OF GLIOBLASTOMA CELLS
Authors: Lorimer Ian , Lavictoire Sylvie , Jomaa Danny , Gont Alex , Jardine Karen 
Published: November 2019

Abstract
Virtually all primary glioblastomas have aberrant activation of the PI 3-kinase pathway through mutational inactivation of tumour suppressors such as PTEN and/or mutational activation of oncogenes. Most glioblastomas also overexpress the Rac guanine nucleotide exchange factor PREX1, which is activated by PI 3-kinase pathway signaling. To determine the role of PREX1 in mediating the effects of aberrant PI 3-kinase pathway signaling in glioblastoma, we used CRISPR/Cas9 to knockout PREX1 in patient-derived glioblastoma cells cultured under conditions that maintain their neural stem cell-like characteristics. Multiple PREX1-null glioblastoma cell clones showed reduced motility and an altered morphology, with a smaller cell body and multiple neurite-like extensions. They also had increased expression of doublecortin, a marker of committed neurogenic progenitor cells. Analysis of RNA-seq data for transcription factor usage was consistent with the acquisition of an intermediate progenitor-like phenotype in PREX1-null cells, with loss of neural stem cell-associated polycomb repressive complex 2 and DMRTA2 activity and the expression of an EOMES/TBR2 signature characteristic of intermediate progenitors. The reduced motility, altered morphology and increase in doublecortin protein levels could all be reversed by re-expression of PREX1. PREX1-null cells had a reduced ability to phosphorylate and inactivate Lgl1, which is required for the maintenance of neural stem cell-like glioblastoma cell populations in vivo. These data show that PREX1 links aberrant PI 3-kinase signaling to maintenance of the neural stem cell-like phenotype in glioblastoma cells.
CSIG-14. PROTEIN KINASE CK2 REGULATES THE EXPRESSION OF NERVE/GLIAL ANTIGEN (NG)2 IN GLIOBLASTOMA
Authors: Schmitt Beate , Sippl Christoph , Urbschat Steffi , Oertel Joachim , Laschke Matthias , Menger Michael , Ampofo Emmanuel 
Published: November 2019

Abstract
Nerve/glial antigen (NG)2 enhances cell proliferation, migration as well as chemoresistance and is associated with a poor clinical outcome in glioblastoma. Since regulatory mechanisms of NG2 expression are still largely unknown, we herein investigated the impact of protein kinase CK2 inhibition on NG2 expression in human glioblastoma cells. CK2 was inhibited in NG2-positive human glioblastoma cell lines (A1207, U87) and primary human glioblastoma cells by pharmacological treatment (CX-4945, TBB) or siRNA. NG2 expression was analyzed by flow cytometry, Western Blot and qRT-PCR. Cytotoxicity and viability were assessed by WST-1, LDH and BrdU assays. Scratch, sprouting and BrdU assays as well as growth curves were performed to examine cell migration and proliferation. Truncated fragments of the human NG2 promotor were generated and their transcriptional activity was assessed using reporter gene assays. The effect of CK2 inhibition on tumor growth was investigated in xenografts within the flanks of NOD/SCID mice. Finally, effects of CK2 inhibition were analyzed in primary human glioblastoma cells. We found that inhibition of CK2 significantly reduces NG2 protein levels in A1207 (19%±6.2; Mean±SD), U87 (35%±11.3) and primary human glioblastoma cells (41%) when compared to controls. Further analyses revealed that this is due to a decreased NG2 mRNA level. Of note, we identified a 200 base pair fragment, including a binding site for the CK2-dependent transcription factor SP-1. Functional assays showed no cytotoxic effects of the decreased NG2 expression after CK2 inhibition, whereas cell migration and proliferation were markedly reduced. Moreover, we found that CX-4945 treatment decreases tumor growth, which is associated with a diminished NG2 expression (56%±13.0) when compared to controls. In conclusion, we identified CK2 as a novel regulator of NG2 gene expression in human glioblastoma cells. Hence, pharmacological inhibition of CK2 may represent a novel strategy in the therapy of NG2-positive glioblastoma.
CSIG-17. SIGNALING PATHWAY-BASED CLUSTERING OF MASS CYTOMETRY DATA UNCOVERS CELLS ASSOCIATED WITH CLINICAL PROGRESSION IN GLIOBLASTOMA
Authors: Alvarado Alvaro , Alban Tyler , Nakano Ichiro , Lathia Justin , Goldman Steven , Kornblum Harley 
Published: November 2019

Abstract
Recent advances in single cell expression technology have allowed us to appreciate the complexity in tumoral heterogeneity of solid tumors such as glioblastoma (GBM), which remains uniformly fatal despite aggressive therapies. Currently, there is no knowledge about cell identities and functional characteristics of the different tumoral populations. To this end, we created a 28-marker mass cytometry panel composed of signaling markers, including phospho-proteins, and lineage markers that have been associated with GBM or are considered putative cancer stem cell markers. We evaluated lines established from core and edge (periphery) areas from the same patient and validated to be functionally different with RNA expression and in vivo experiments. We first clustered the cells from all samples using the signaling markers in order to establish differences based on pathway utilization, and then we evaluated the expression of all markers. We found clusters shared by cells from both regions as well as region-specific ones. In order to better characterize these, we used marker enrichment modeling (MEM) and generated machine-readable labels. These were compared to MEM labels generated after using the same signaling markers to cluster primary samples from newly diagnosed or recurrent patients. Similarly, MEM labels were obtained from patients in a clinical trial treated with capecitabine that had positive or negative responses. Clusters from edge cells were found in higher proportion in recurrent tumors and were correlated with negative responses to the chemotherapeutic agent. Initial analyses have also been done correlating immune clusters with tumor clusters in the same samples. We are currently conducting in vitro studies and analyzing additional lines from other patients in order to validate these findings. Our studies exploit single cell cytometry to underscore pathways that are preferentially use by different cell populations with the ultimate goal of establishing therapeutic efforts to extend patient survival.