Brain Tumor Research Research Articles

Caveolin-1, a driver of invasive phenotype in in-vitro 3D-spheroid assays comprised of high grade GBM cells association with an AKT-inhibited phenotype

INTRODUCTION Glioblastoma multiforme (GBM) cells display a highly invasive phenotype, a hallmark which counters effective surgical and radiotherapy strategies. Caveolin-1 (Cav-1) is the main structural and functional component of caveolae. The impact of the expression of Cav-1 within a range of tumour and tumour-associated stromal cells is variable with both oncogenic and tumour suppressive roles reported which appear to be both disease-specific and context-dependent. Our hypothesis is that Cav-1 serves as promoter of invasion of GBM cells. MATHERIALS AND METHODS To investigate our hypothesis we used a lentiviral shRNA approach to silence Cav-1 in three GBM cell lines (U87, UP007, UP029) derived from adult brain tumours. We employed an in-vitro 3D cell-sprouting invasion assay with GBM cell spheres embedded in Matrigel. Quantification of invasion was undertaken using a novel image analysis tool or 3D systems, INSIDIA (ImageJ Macro for High-throughput Spheroid Invasion Analysis). Parallel migration and invasion studies were performed using a Boyden Chamber approach, as well as cell-cell adhesion assays. Activation of signalling pathways in 2D and 3D cultures were performed by proteomic array and Western Blot analysis. RESULTS AND CONCLUSION GBM cells expressing Cav-1 (Cav-1 +ve) displayed a higher invasive capacity compared cells where Cav-1 had been silenced Cav-1 –ve), the latter also showing increased cell-cell adhesion. A significant finding from the signalling analysis was an inverse association between Cav-1 silencing and activation of AKT evidenced by increased phosphorylation at both Ser473 and Thr308 sites. Ongoing studies are exploring this signalling axis and its relationship to the invasive phenotype. CM and MG acknowledge Cancer Research Wales support. GP and HF acknowledge Brain Tumour Research support.

Expression and tumor-promoting effects of caprin-1 in human glioma

Background: Cytoplasmic activation/proliferation-associated protein-1 (caprin-1) is a newly discovered RNA-binding protein and is now recognized as one of the putative oncogenes. This study was performed to reveal its presence in human gliomas and its oncogenic functions in human glioblastoma-derived Denver brain tumor research group 05 (DBTRG-05MG) cells. Materials and Methods: Clinical glioma samples were cumulatively collected for the identification of caprin-1 using immunoblot analysis and immunofluorescence detection. DBTRG cells transfected with caprin-1-specific small interfering RNA (siRNA) were used to verify caprin-1's oncogenic function using a real-time cell analyzer (RTCA) and scratch assay. Results: Seven of eight collected glioma samples were identified as positive for caprin-1 expression. siRNA dose-responsive inhibition of cell proliferation was observed in DBTRG cells with RTCA, and cell migration rate was significantly reduced by siRNA transfection (P

Brain tumor research in the United Kingdom: current perspective and future challenges. A strategy document from the NCRI Brain Tumor CSG.

The National Cancer Research Institute (NCRI) is a partnership of charity and government research funders whose purpose is to improve health and quality of life by accelerating progress in cancer-related research through collaboration. Under this umbrella, the NCRI Brain Tumor Clinical Studies Group is focused on improving clinical outcomes for adult patients with brain and central nervous system tumors, including those with brain metastasis from other primary sites. This document discusses the current state of clinical brain tumor research in the United Kingdom and the challenges to increasing study and trial opportunities for patients. The clinical research priorities are defined along with a strategy to strengthen the existing brain tumor research network, improve access to tissue and imaging and to develop the future leadership for brain tumor research in the United Kingdom. This strategy document may serve as a framework for other organizations and countries.

Novel strategies of Raman imaging for brain tumor research.

Raman diagnostics and imaging have been shown to be an effective tool for the analysis and discrimination of human brain tumors from normal structures. Raman spectroscopic methods have potential to be applied in clinical practice as they allow for identification of tumor margins during surgery. In this study, we investigate medulloblastoma (grade IV WHO) (n= 5), low-grade astrocytoma (grades I-II WHO) (n =4), ependymoma (n=3) and metastatic brain tumors (n= 1) and the tissue from the negative margins used as normal controls. We compare a high grade medulloblastoma, low grade astrocytoma and non-tumor samples from human central nervous system (CNS) tissue. Based on the properties of the Raman vibrational features and Raman images we provide a real–time feedback method that is label-free to monitor tumor metabolism that reveals reprogramming of biosynthesis of lipids, proteins, DNA and RNA. Our results indicate marked metabolic differences between low and high grade brain tumors. We discuss molecular mechanisms causing these metabolic changes, particularly lipid alterations in malignant medulloblastoma and low grade gliomas that may shed light on the mechanisms driving tumor recurrence thereby revealing new approaches for the treatment of malignant glioma. We have found that the high-grade tumors of central nervous system (medulloblastoma) exhibit enhanced level of β-sheet conformation and down-regulated level of α-helix conformation when comparing against normal tissue. We have found that almost all tumors studied in the paper have increased Raman signals of nucleic acids. This increase can be interpreted as increased DNA/RNA turnover in brain tumors. We have shown that the ratio of Raman intensities I2930/I2845 at 2930 and 2845 cm-1 is a good source of information on the ratio of lipid and protein contents. We have found that the ratio reflects the different lipid and protein contents of cancerous brain tissue compared to the non-tumor tissue. We found that levels of the saturated fatty acids were significantly reduced in the high grade medulloblastoma samples compared with non-tumor brain samples and low grade astrocytoma. Differences were also noted in the n-6/n-3 polyunsaturated fatty acids (PUFA) content between medulloblastoma and non-tumor brain samples. The content of the oleic acid (OA) was significantly smaller in almost all brain high grade brain tumors than that observed in the control samples. It indicates that the fatty acid composition of human brain tumors differs from that found in non-tumor brain tissue. The iodine number NI for the normal brain tissue is 60. For comparison OA has 87, docosahexaenoic acid (DHA) 464, α-linolenic acid (ALA) 274. The high grade tumors have the iodine numbers between that for palmitic acid, stearic acid, arachidic acid (NI=0) and oleic acid (NI=87). Most low grade tumors have NI similar to that of OA. The iodine number for arachidonic acid (AA) (NI=334) is much higher than those observed for all studied samples.

Abstract 2593: Accelerating pediatric brain tumor research through team science solutions

Abstract Introduction: The Children’s Brain Tumor Tissue Consortium (CBTTC), an international repository of genomic and phenotypic data, has partnered with Blackfynn, Inc., to create a cloud-based data management platform to facilitate team-science across disciplines. Background: The CBTTC through the CHOP Department of Biomedical and Health Informatics (DBHi) has developed a network of informatics and data applications for researchers across the globe to work together and perform real-time analyses on existing clinical, phenotypic, and genomic data. Historically, rare disease datasets are siloed, locked in proprietary formats, segregated by data types, and hidden from the view of experts in the field. This has been a significant barrier to finding effective therapeutics for children with pediatric brain tumors. Blackfynn was founded by a group of multidisciplinary experts in neuroscience, neurology, medicine, software development, engineering, computer science and business with the goal to empower researchers to cure neurologic disease and provide solutions to these challenges. Description of Methods: The CBTTC and Blackfynn teamed up to provide a cloud-based, team-focused data management and analytics platform. The platform provides a commercial grade, scalable approach to upload, view, and integrate digital pathology images with relevant subject data such as MRIs, pathology reports and genomic information. Stakeholders can search integrated data without requiring users to change their current workflow or conform to imposed data standards. This platform is a simple, intuitive, end-to-end software platform for teams of scientists and pathologists to review, annotate and discuss cases, enabling rapid diagnostic consensus, quality control, and empowered discovery. Summary of Unpublished Results: The CBTTC/Blackfynn data platform enabled CBTTC members to engage in a cross-institutional collaboration to reach consensus on digital pathology data in ways that were previously not possible. We demonstrated that this solution removes existing barriers to collaborative efforts and provides a rich analytic and discovery platform bridging imaging with genomics and other data formats. The platform provides a new model for the scientific community to facilitate translation towards improved treatments for children diagnosed with brain tumors. Discussion and Future Direction: This pilot project will be scaled to other CBTTC sites for centralized review of pathology images to enable the research community to collaborative on specific projects. The next phase of platform development will include further integration CBTTC platforms fully integrating genomics data, and side-by-side viewing and analyses of MRI, pathology and clincal data to facilitate specific project work around large and complex research data types in a cloud environment. Citation Format: Amanda Christini, Angela J. Waanders, Joost B. Wagenaar, Alex S. Felmeister, Mariarita Santi, Nitin R. Wadhwani, Jennifer L. Mason, Mateusz P. Koptyra, Jena V. Lilly, Jeffrey W. Pennington, Rishi R. Lulla, Adam C. Resnick. Accelerating pediatric brain tumor research through team science solutions [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 2593. doi:10.1158/1538-7445.AM2017-2593

P.040 Moncton brain tumour tissue biorepository: diagnostic and therapeutic initiatives for glioma research in New Brunswick

Background: Improving diagnostic and therapeutic tools associated with glioblastoma multiforme (GBM), an aggressive brain tumour, is crucial as average patient survival remains slightly over a year. Challenges include early diagnosis and acquired drug resistance. Improving these challenges notably require a multidisciplinary team and a dedicated brain tumour specimen collection initiative. We hypothesize that implementing such an approach in Moncton would provide significant benefits to GBM patients and researchers in New Brunswick. Methods: A Brain Tumour Tissue Repository was instigated to collect and preserve primary tumour specimens. Storage of circulating samples from patients undergoing temozolomide (TMZ) therapy was also performed. In parallel, molecular leads were investigated in different GBM models to identify therapeutic targets. Results: Collection of 7 primary specimens was accomplished in 2016. Over 15 primary samples are housed in the tumour biorepository to date with circulating samples collected from 3 patients. Additionally, numerous deregulated non-coding RNAs were identified by qRT-PCR in GBM models and shown to be modulated following TMZ treatment warranting further investigation. Conclusions: Overall, these results provide novel therapeutic leads for GBMs and, most importantly, highlight the instigation of a New Brunswick-based brain tumor biorepository which will undoubtedly strengthen brain tumour research in the Maritimes.

Proliferations and Vulnerabilities: Hybridization of Professionalism in the Field of Cancer Medicine

In cancer medicine, particularly in drug research and development, structural changes in professionalism can be observed as examples. This field is characterized by a strong tension between social expectations concerning the control of existential risks to health, on the one hand, and strong commercial interests of a shareholder value-driven industry, on the other hand. Based on a qualitative empirical analysis, two subfields within the field of cancer medicine are reconstructed. One of these subfields—colon cancer therapy—could be interpreted as representing a renewal of the knowledge-power nexus. The pattern of the other subfield—brain tumour research—refers to a much more vulnerable professionalism. Both fields are characterized by development in professional work, which could be described with the hybridization concept. Therefore, the contrast between the two empirical examples presented still challenges the theoretical interpretation of contemporary professionalism.

Multimodal therapy for brain tumors ⁎

Ting Lei. M.D., Professor of Neurosurgery, Doctoral Supervisor, Director of the Neurosurgery Department, Tongji Hospital, Tongji Medical College of Huazhong University of Science and Technology, China. He obtained his bachelor’s and master’s degree from Tongji Medical University, China, and became a neurosurgeon afterward. Then, he successfully obtained a German Academic Exchange Service scholarship to undertake his doctorate in medicine at the University of Erlangen-Nuernberg in Germany. Under the supervision of Profs. R. Fahlbusch and M. Buchfelder, he completed his doctoral degree in the same university and returned to Tongji Hospital to become the first postdoctoral fellow in the Department of Neurosurgery. Since 1998, he has been Chief of the Neurosurgical Department. His scientific interest is basic research and clinical treatment of brain tumors, including pituitary adenoma and glioma. He introduced transsphenoidal surgery in the treatment of pituitary adenoma in Hubei Province, China. Currently, he performs more than 300 transsphenoidal surgeries annually. Over the past years, he also modified this surgical approach to make it less invasive and provide patients with fast postoperative recovery and better quality of life. He has been an active researcher in the brain tumor research community for over 30 years now. He received several grants from the National Natural Science Foundation and published more than 500 peer-reviewed papers in national and international journals, including the Journal of Neurosurgery, Epilepsy, European Journal of Cancer, and Cancer Letter. Meanwhile, he is also an academic editor of several journals. Prof. Lei serves as the chairman of the neurosurgery branch of the Wuhan Medical Association and is a committee member of several academic associations.

EPN-09KETOLYTIC AND GLYCOLYTIC ENZYMATIC EXPRESSION IN PAEDIATRIC EPENDYMOMAS: IMPLICATION FOR KETOGENIC DIET THERAPY

EPN-09. KETOLYTIC AND GLYCOLYTIC ENZYMATIC EXPRESSION IN PAEDIATRIC EPENDYMOMAS: IMPLICATION FOR KETOGENIC DIET THERAPY Lisa C.D. Storer1, Angeline Darren1, Simon M.L. Paine2, Jen Kearns3, Robert Layfield4, David A. Walker1, and Richard G. Grundy1; Children’s Brain Tumour Research Centre, School of Medicine, University of Nottingham, Nottingham, UK; Department of Neuropathology, Nottingham University Hospitals NHS Trust, Nottingham, UK; Division of Nutritional Sciences, University of Nottingham, Nottingham, UK; School of Life Sciences, University of Nottingham, Nottingham, UK Ependymoma is the second most common paediatric malignant brain tumour. Overall survival remains relatively poor, and at relapse is dismal. One potential strategy to improve outcome is exploiting the metabolic differences between normal and tumour cells. Under normal physiological conditions, brain cells metabolise glucose for energy. If “starved” of glucose, ketone bodies are metabolised. Mitochondrial defects in brain tumour cells obviate this metabolic flexibility resulting in a dependence on glycolytic energy (Warburg effect). Thus, a high fat, low carbohydrate ketogenic diet (KD) may control tumour growth. We evaluated the expression of ketolytic enzymes; succinyl-CoA:3-oxoacid CoA transferase 1 (OXCT1) and D-b-hydroxybutyrate dehydrogenase 1 (BDH1), both involved in ketone body utilization and the glycolytic enzyme; pyruvate kinase M2 (PKM2), essential for aerobic glycolysis, in 75 paediatric ependymomas by immunohistochemistry. Expression was assessed as low (,20%) or high (.20%).84%showed lowexpression of OXCT1 and 91% of BDH1. Lowexpression of either results in an inability to metabolise ketones. 82% showed high expression of PKM2, increasing the Warburg effect and when combined with low expression of BDH1 (69%) or OXCT1 (83%), the optimal immunohistochemistry profile, arrests ketone metabolism. Children aged ,36 months were 5 times less likely to show high expression of OXCT1 compared to ≥36 months (p 1⁄4 0.0321) and 7 times more likely to show high expression of PKM2 (p 1⁄4 0.0097). The KD therefore offers a potential addition to current therapies including at relapse. However, the KD would need to be carefully evaluated prior to acceptance as a useful additional therapy. Neuro-Oncology 18:iii30–iii39, 2016. doi:10.1093/neuonc/now070.8 #The Author(s) 2016. Published by Oxford University Press on behalf of the Society for Neuro-Oncology. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Creation of an NCI comparative brain tumor consortium: informing the translation of new knowledge from canine to human brain tumor patients.

On September 14-15, 2015, a meeting of clinicians and investigators in the fields of veterinary and human neuro-oncology, clinical trials, neuropathology, and drug development was convened at the National Institutes of Health campus in Bethesda, Maryland. This meeting served as the inaugural event launching a new consortium focused on improving the knowledge, development of, and access to naturally occurring canine brain cancer, specifically glioma, as a model for human disease. Within the meeting, a SWOT (strengths, weaknesses, opportunities, and threats) assessment was undertaken to critically evaluate the role that naturally occurring canine brain tumors could have in advancing this aspect of comparative oncology aimed at improving outcomes for dogs and human beings. A summary of this meeting and subsequent discussion are provided to inform the scientific and clinical community of the potential for this initiative. Canine and human comparisons represent an unprecedented opportunity to complement conventional brain tumor research paradigms, addressing a devastating disease for which innovative diagnostic and treatment strategies are clearly needed.

Report of the Jumpstarting Brain Tumor Drug Development Coalition and FDA clinical trials clinical outcome assessment endpoints workshop (October 15, 2014, Bethesda MD).

On October 15, 2014, a workshop was held on the use of clinical outcome assessments in clinical trials for high-grade glioma of the brain. This workshop was sponsored by the Jumpstarting Brain Tumor Drug Development Coalition, consisting of the National Brain Tumor Society, the Society for Neuro-Oncology, the Musella Foundation for Brain Tumor Research and Information, and Accelerate Brain Cancer Cure. It was planned and carried out with participation from the US Food and Drug Administration. The workshop also included stakeholders from all aspects of the brain tumor community, including clinicians, researchers, industry, clinical research organizations, patients and patient advocates, and the National Cancer Institute. This report summarizes the presentations and discussions of that workshop and the proposals that emerged to move the field forward and toward greater inclusion of these endpoints in future clinical trials for high-grade gliomas.

Neuro-oncology biotech industry progress report.

The Brain Tumor Biotech Center at the Feinstein Institute for Medical Research, in collaboration with Voices Against Brain Cancer hosted The Brain Tumor Biotech Summit at in New York City in June 2015. The focus was once again on fostering collaboration between neuro-oncologist, neurosurgeons, scientists, leaders from biotechnology and pharmaceutical industries, and members of the financial community. The summit highlighted the recent advances in the treatment of brain tumor, and specifically focused on targeting of stem cells and EGFR, use of prophage and immunostimulatory vaccines, retroviral vectors for drug delivery, biologic prodrug, Cesium brachytherapy, and use of electric field to disrupt tumor cell proliferation. This article summarizes the current progress in brain tumor research as presented at 2015 The Brain Tumor Biotech Summit.

The Molecular Era of Brain Tumour Research is upon us: But what now for our Patients?

The Molecular Era of Brain Tumour Research is upon us: But what now for our Patients?

Tailoring PLGA nanoparticle release profiles via centrifugal fractioning

Event Abstract Back to Event Tailoring PLGA nanoparticle release profiles via centrifugal fractioning Dipankar Dutta1*, Mariama Salifu1*, Rachael W. Sirianni1, 2* and Sarah E. Stabenfeldt1* 1 Arizona State University, School of Biological and Health Systems Engineering, United States 2 Barrow Neurological Institute, Barrow Brain Tumor Research Center, United States Introduction: Poly(D,L-lactic-co­-glycolic) acid (PLGA)-based nanoparticles (NP) are uniquely posed to overcome limitations of conventional drug delivery systems. However, tailoring cargo/payload release profiles from PLGA NPs typically requires the optimization of the multi-parameter NP formulation, where small changes may cause drastic shifts in the resulting release profiles[1],[2]. In this study, we aimed to establish whether refining the average diameter of NP populations through centrifugal fractioning after particle formulation represents a feasible tool to tailor PLGA NP release characteristics. We hypothesized that the average NP size would directly affect protein loading and subsequent release characteristics. Materials and Methods: PLGA NPs were produced via double-emulsion followed by solvent evaporation to encapsulate the model protein, bovine serum albumin (BSA). NPs were then subjected to centrifugal fractioning protocols varying in both spin time and force. After separation of supernatant and pellet, NP size distributions of initial and fractioned groups were determined using scanning electron microscopy. Release profiles were quantified by determining protein encapsulation efficiencies and in vitro release assays. Statistical analyses were performed using analysis of variance with Tukey’s post-hoc test. Results and Discussion: Centrifugal fractioning significantly modulated NP size distribution as a function of spin time and force without negatively affecting yield and NP morphology. Average diameters for all groups in the study ranged between 211.2–707.5nm relative to 340.9nm for the initial batch of NPs. Additionally, we found the average NP diameter was related to marked alterations in encapsulation efficiencies (range: 36.4-49.4%; Fig 1A), burst release (range: 15.8-49.1%; Fig 1B), protein release rate (Fig 1C), and time for total cargo release (range: 38-78 days; Fig 1D). Our data corroborated previous reports relating NP size with such release characteristics[3],[4]. However, this is the first study, to our knowledge, to directly compare NP population size and protein release profile while holding all formulation parameters constant. Conclusion: Previous studies have evaluated the influence of the fabrication parameters on the cargo loading and release from PLGA particles to provide general formulation trends on obtaining broad release profile characteristics. However, seemingly simple changes in the NP formulation may ultimately lead to a loss of desirable attribute(s). We report that protein encapsulation efficiency and several parameters of the release curve are correlated to t. Thus centrifugal fractioning represents a potential tool for tuning NP properties without modifying formulation parameters. Figure 1: Encapsulation efficiency and duration of release was directly proportional to the average particle diameter (A and D). Conversely, the magnitude of the burst release and the rate of protein release were inversely proportional to average particle diameter (B and C). Linear regression was used to empirically model trends (solid line) with 95% confidence interval (dotted lines). NIH (1DP2HD084067; SES); NSF (1454282; SES); ASU Start-up Funds (SES); Ben and Catherine Ivy Foundation (RWS); DoD (W81XWH-14-1-0311; RWS)

Probing the mechanism of targeted nanoparticle drug delivery to the brain using covalently linked, multispectral quantum dots

Event Abstract Back to Event Probing the mechanism of targeted nanoparticle drug delivery to the brain using covalently linked, multispectral quantum dots Kyle T. Householder1, 2, David X. Medina1, Ricki Ceton1, 2, Danielle M. Diperna1, Rebecca L. Cook1, 2 and Rachael W. Sirianni1, 2 1 Barrow Neurological Institute, Barrow Brain Tumor Research Center, United States 2 Arizona State University, United States Introduction: Effective treatment of brain disorders remains a major clinical challenge due to the blood-brain-barrier (BBB). Surface modification of nanoparticles (NPs) with targeting ligands has been shown to improve delivery and efficacy of encapsulated drugs in the brain. However, whether this improvement reflects transport of NPs across the BBB remains under active debate. We recently observed that delivery of a small molecule from brain-targeted NPs varied by as much as 80% across brain regions, which was driven by differences in regional blood flow for both control (CTR) and targeted NPs[1]. Here, we developed a multispectral labeling strategy to test the hypothesis that payload delivery from brain-targeted NPs occurs in absence of NP movement across the BBB. Methods: NPs were produced by single emulsion, and post-modified with rabies virus glycoprotein (RVG) or the transactivator of transcription of HIV (TAT). Nile red (NR) was encapsulated to measure payload delivery by fluorescence in brain homogenates of healthy mice. NH2-quantum dots (QD) were linked to carboxy-poly(lactide)-b-poly(ethylene glycol) by EDC chemistry and blended with parent polymer (QD-NP) for NP tracking by confocal microscopy. NP size and zeta potential were measured by dynamic light scattering. Cell viability was measured by Cell TiterGlo. Healthy or intracranial GL261 tumor bearing C57 mice were perfused by cardiac puncture 0.5, 2, 6, or 24 hrs after tail vein injection of NPs. Results: TAT and RVG increased NR delivery to the brain by 79% and 51% relative to CTR NPs at 2 hrs, demonstrating ligand functionality. QD-NPs were confirmed to be nontoxic in HEK cells (up to 5 mg/ml NP) after 24 hr incubation.NP size did not significantly change across formulations (p=0.96, 1-way ANOVA), and all formulations had zeta potentials between -2 and -7 mV. In vitro NR leached rapidly into cells, whereas punctate QD signal was only observed after several hours (Fig 1). Targeting increased NP uptake by HEK cells in vitro (Fig 2); however, exhaustive imaging analysis failed to reveal TAT or RVG QD-NPs in BBB cells or parenchyma of healthy mice at any time point (not shown). In contrast, QD-NPs were readily visualized in peripheral organs. For example, RVG and CTR QD-NPs co-administered to single mice could both be detected in spleen at 2 hrs but only RVG-QD-NPs were observed at 24 hrs (Fig 3A). QD-NPs administered to intracranial tumor bearing mice were also easily detected in the malformed vasculature of the tumor core at 2 hrs, presumably due to the enhanced permeation and retention effect (Fig 3B), but did not enter the parenchyma, even at later time points. Conclusions: QD-NPs are stable, nontoxic, have reproducible biophysical properties, and can be used to track NP distribution with subcellular resolution in vitro and in vivo. Our data confirm that ligand modification improves payload delivery to the brain, but we observed no evidence for NP transport across an intact BBB. NPs were, however, able to access the leaky core of intracranial tumors. These results demonstrate discordance between delivery of payload vs intact NPs and support a model for CNS-targeted delivery based on transfer of drug from NP to cells in absence of significant NP internalization.

PNIPAAm-based biohybrid injectable hydrogel for cardiac tissue engineering

Event Abstract Back to Event PNIPAAm-based biohybrid injectable hydrogel for cardiac tissue engineering Ali Navaei1, Danh Truong1, John Heffernan1, Josh Cutts1, David Brafman1, Rachael Sirianni1, 2, Brent Vernon1 and Mehdi Nikkhah1 1 Arizona State University, School of Biological and Health Systems Engineering, United States 2 Barrow Neurological Institute, Barrow Brain Tumor Research Center, United States Injectable biomaterials offer a non-invasive method to deliver cells into the myocardial infarct region to maintain an adequate level of cellular retention and viability and promote the regeneration process. However, conventional injectable matrices suffer from either low bioactivity or poor mechanical properties. To that extent, in this work we introduced a biohybrid temperature-responsive PNIPAAm-Gelatin-based injectable hydrogel, with excellent bioactivity and mechanical robustness for cardiac tissue engineering. A unique feature of our work was performing extensive in vitro biological analyses to assess the functionalities of cardiomyocytes (CMs) alone and in co-culture with cardiac fibroblasts (CFs) within the hydrogel matrix. The synthesized injectable hydrogel exhibited suitable viscoelastic behavior and adequate water content to properly accommodate the cardiac cells. The encapsulated cells demonstrated a high level of survival and spreading throughout the matrix in both culture groups. A dense network of F-actin fibers illustrated the formation of an intact and three dimensional (3D) cardiac tissue construct within the hydrogel matrix. Furthermore, immunostaining images revealed typical phenotypic characteristics in cardiac cells. Interestingly, the co-culture group exhibited significant improvements in structural organization, cell-cell coupling, genes expression, as well as beating behavior. This study opens a new avenue for extensive in vitro characterizations of injectable matrices, using mono- and co-culture of cardiac cells, prior to in vivo experiments. Keywords: Hydrogel, Regenerative Medicine, MYOCARDIAL TISSUE, Cell functionality Conference: 10th World Biomaterials Congress, Montréal, Canada, 17 May - 22 May, 2016. Presentation Type: New Frontier Oral Topic: Biomaterials in constructing tissue substitutes Citation: Navaei A, Truong D, Heffernan J, Cutts J, Brafman D, Sirianni R, Vernon B and Nikkhah M (2016). PNIPAAm-based biohybrid injectable hydrogel for cardiac tissue engineering. Front. Bioeng. Biotechnol. Conference Abstract: 10th World Biomaterials Congress. doi: 10.3389/conf.FBIOE.2016.01.02417 Copyright: The abstracts in this collection have not been subject to any Frontiers peer review or checks, and are not endorsed by Frontiers. They are made available through the Frontiers publishing platform as a service to conference organizers and presenters. The copyright in the individual abstracts is owned by the author of each abstract or his/her employer unless otherwise stated. Each abstract, as well as the collection of abstracts, are published under a Creative Commons CC-BY 4.0 (attribution) licence (https://creativecommons.org/licenses/by/4.0/) and may thus be reproduced, translated, adapted and be the subject of derivative works provided the authors and Frontiers are attributed. For Frontiers’ terms and conditions please see https://www.frontiersin.org/legal/terms-and-conditions. Received: 27 Mar 2016; Published Online: 30 Mar 2016. Login Required This action requires you to be registered with Frontiers and logged in. To register or login click here. Abstract Info Abstract The Authors in Frontiers Ali Navaei Danh Truong John Heffernan Josh Cutts David Brafman Rachael Sirianni Brent Vernon Mehdi Nikkhah Google Ali Navaei Danh Truong John Heffernan Josh Cutts David Brafman Rachael Sirianni Brent Vernon Mehdi Nikkhah Google Scholar Ali Navaei Danh Truong John Heffernan Josh Cutts David Brafman Rachael Sirianni Brent Vernon Mehdi Nikkhah PubMed Ali Navaei Danh Truong John Heffernan Josh Cutts David Brafman Rachael Sirianni Brent Vernon Mehdi Nikkhah Related Article in Frontiers Google Scholar PubMed Abstract Close Back to top Javascript is disabled. Please enable Javascript in your browser settings in order to see all the content on this page.

Improving Brain Tumor Research in Resource-Limited Countries: A Review of the Literature Focusing on West Africa.

Neoplasms of the brain are often overlooked in resource-limited countries. Our literature search via AJOL and PubMed demonstrated that brain tumor research is still a rarity in these regions. We highlight the current status, importance, challenges, and methods of improving brain tumor research in West Africa. We suggest that more attention be given to basic, clinical, and epidemiological brain tumor research by national governments, private organizations, international organizations, non-governmental organizations (NGOs), and individuals in this region.

TMIC-06GLIOMA-MEDIATED MICROGLIAL ACTIVATION PROMOTES GLIOMA PROLIFERATION AND MIGRATION: ROLES OF NA + /H+ EXCHANGER 1

Glioma-associated microglia and macrophages (GAMs) comprise up to 30% of the brain tumor mass, making them substantial contributors to the tumor environment. Once within the tumor niche, infiltrating GAMs are quickly converted to pro-tumorigenic phenotypes that enhance glioma growth and migration. Here we have characterized the role of Na + /H+ exchanger isoform-1 (NHE1) in the bidirectional communication between glioma cells and microglia. NHE1 protein expression was increased in tumor xenographs in both microglia and glioma cells. We found that microglia cells exposed to glioma-conditioned medium increased their NHE1 expression, as well as expression of the M1 marker iNOS and the M2 marker Arg1. This is in accordance with the mixed activation profile observed with GAMs. The levels of a panel of other candidates were also evaluated, revealing a large increase in expression of the cytokines IL6, IL10, and TGFβ as well as membrane type 1-matrix metalloproteinase (MT1-MMP) and matrix metalloproteinase 9. Regulation of all these proteins was abolished when NHE1 protein in microglia was inhibited with the selective NHE1 inhibitor HOE642. We next looked at the communication from glioma-stimulated microglia back to glioma cells. Glioma cells were exposed to conditioned medium from glioma-stimulated microglia grown with or without the NHE1 inhibitor HOE642. Glioma cells treated with glioma/microglia conditioned medium showed increased levels of phosphylated-Akt, increased proliferation, and enhanced migration, but not if microglial NHE1 function had been blocked by HOE 642. Our results show that NHE1 plays important roles in both the activation of microglia in response to tumor-secreted signals as well as microglial production of secreted signals which stimulate tumor progression. Thus, NHE1 is a promising therapeutic target for the treatment of glioma. Funding sources include NIH grants R01NS075995 and R01NS048216, the HEADRUSH Brain Tumor Research Professorship, the Roger Loff Memorial GBM Research Fund, and Department of Neurological Surgery.

DDEL-03INTRAVENOUS NANOPARTICLE DELIVERY TO GLIOBLASTOMA

A major obstacle in the treatment of glioblastoma (GBM) is the blood brain barrier (BBB), which restricts drug molecules in the bloodstream from reaching the tumor. The BBB may be disrupted at or near the GBM tumor core, but it is intact at the growing edge of the tumor, where invasive cells reside and can cause disease recurrence. To combat GBM more effectively, novel drug transport technology that crosses intact BBB is urgently needed. Brain microvascular endothelial cells (BMEC) found in the BBB are lined with low-density lipoprotein receptors (LDLr) and LDL-like receptor proteins (LRP), which are essential to the endocytosis/ transcytosis processes of BMEC. GBM cells are known to express higher levels of LDLr and LRP than normal brain cells. The objective of our research is to develop a novel lipid nanoparticle (NP) that targets LDLr and LRP to facilitate BMEC endocytosis/ transcytosis and GBM uptake. We focused on developing antisense oligonucleotides (oligos) as the drug cargo for our NP. Less than 20% of disease-associated genes are targetable by conventional drug molecules; however, we hypothesize that disease-associated genes, like EZH2 and ZEB1 transcriptional repressors, are amendable to antisense oligo inhibition. We engineered a novel NP which is composed of neutral lipids: phosphatidylcholine (PC), cholesterol (Chol) and a polymer called poloxamer (PXR). Toxicology studies indicated that NP composed of PC/Chol/PXR did not have adverse effects on mice. Flow cytometry and fluorescent microscopy revealed that PC/Chol/PXR NP was avidly taken up by BMEC, and that PC/Chol/PXR efficiently delivered antisense oligos to GBM cells. Additionally, intravenous injection of PC/Chol/PXR led to deposition of antisense oligos in intracranial GBM xenografts. Future studies will determine the efficacy of the innovative PC/Chol/PXR NP in suppressing target gene expression in intracranial GBM. (Supported by Florida Center for Brain Tumor Research and Accelerate Brain Cancer Cure).

Integrating radiation therapy with emerging systemic therapies: Lessons from a patient with cerebral radionecrosis, spinal cord myelopathy, and radiation pneumonitis

Medical Oncology, Christie NHS Foundation Trust, Manchester, UK University of Manchester, Manchester Cancer Research Centre, Manchester Academic Health Science Centre, Christie NHS Foundation Trust, Manchester, UK The Children's Brain Tumour Research Network, University of Manchester, UK Cancer Research UK Manchester Institute, University of Manchester, the Christie NHS Foundation Trust, Manchester, UK School of Medicine, University of Queensland, Brisbane, Australia