Glioblastoma is the most common primary brain tumour in adults. Despite the aggressive standard of care currently used, median patient survival following treatment is only 14 months. Innovative treatment options are needed for these patients. Recently, oncolytic viruses have emerged as promising immunotherapies for the treatment of solid tumours. Preliminary work in our lab has demonstrated that Farmington virus, a novel brain-safe oncolytic rhabdovirus, can be engineered to encode a tumour-associated antigen (TAA) to prime and boost antigen-specific adaptive immune responses. Since other rhabdoviruses share this boosting capacity, a heterologous rhabdovirus prime/boost regimen can be designed to combine two powerful oncolytics and a robust anti-TAA adaptive immune response. We evaluated Farmington’s ability to vaccinate against a self- glioblastoma antigen and two foreign glioblastoma-associated antigens. Farmington was able to vaccinate against the foreign antigens, leading to efficacy in prophylactic and therapeutic glioblastoma models. Additionally, treatment with heterologous rhabdoviruses demonstrated efficacy in an aggressive murine mammary carcinoma model. Herein, we demonstrate promising preliminary results for a novel glioblastoma therapeutic approach. Le glioblastome est la tumeur primaire la plus fréquente chez l’adulte. La survie moyenne des patients n’excède pas 14 mois malgré une prise en charge thérapeutique agressive. Par conséquent, la mise au point de traitements innovants et efficaces est une nécessité pour ces patients. Des avancées récentes ont mise en évidence l’intérêt des virus oncolytiques dans le traitement des tumeurs solides. Des travaux préliminaires réalisés au sein de notre laboratoire ont, en effet, démontré que le virus Farmington pouvait être modifié afin d’exprimer un antigène associé aux tumeurs (AAT), pour initier et potentialiser une réponse immunitaire adaptative spécifique. D’autres rhabdovirus possèdent des capacités de potentialisation immunitaire similaires et peuvent être utilisés en association avec le virus Farmington modifié pour amorcer et amplifier la réponse immunitaire oncolytique de l’hôte. Le but de ce projet était d’évaluer le potentiel du virus Farmington comme vaccin contre des antigènes tumoraux d’origine endogène ou exogène associés au glioblastome. Nos résultats ont montré que le virus Farmington a la capacité d’induire une réponse immunitaire prophylactique et thérapeutique contre les antigènes tumoraux exogènes dans des modèles de glioblastome. De plus, l’utilisation de rhabdovirus hétérologues s’est aussi révélée efficace pour le traitement de carcinome mammaire agressif chez la souris. Cette étude préliminaire apporte des résultats prometteurs pour le développement de nouvelles approches thérapeutiques efficaces dans le traitement du glioblastome.

Made available in DSpace on 2014-06-12T23:03:12Z (GMT). No. of bitstreams: 2 arquivo8791_1.pdf: 2283735 bytes, checksum: 1046687aa31d4b605b161ab475c9b576 (MD5) license.txt: 1748 bytes, checksum: 8a4605be74aa9ea9d79846c1fba20a33 (MD5) Previous issue date: 2005 / O Glioblastoma Multiforme (GBM) é o tumor glial com maior grau de malignidade. Acomete principalmente os hemisférios cerebrais apresentando sintomas e sinais focais ou gerais, relacionados ao tamanho, localização e taxa de crescimento tumoral. Objetivo: Analisar a relação do déficit motor com a topografia do GBM. Método: Foram estudados 43 casos de GBM, referidos quanto à idade, sexo, localização e a síndrome motora. Resultados: o tumor predominou em adultos (média de 55 anos), sexo masculino (55,82%), localização frontal (aproximadamente 40%). A hemiparesia prevaleceu como distúrbio motor, somente não ocorrendo em 2 casos de lesão frontal, 2 temporais, 1 parietal, 1 occipital e 1 fronto-temporal. Conclusão: Os achados clínico-topográficos favorecem os efeitos infiltrativos (lesões extensas) como responsáveis pela síndrome motora em detrimento aos efeitos compressivos (lesões localizadas)

Glioblastoma (GBM) is an aggressive brain cancer with devastating outcomes and few effective treatments. Although immunotherapy has shown promise in treating a variety of cancers, it is still unclear if and how it can be effectively used in GBM. Elucidating this will require a better understanding of the mechanistic role of immune cells and their interactions in the GBM tumor microenvironment. This thesis utilizes recent technological developments in cancer genomics and imaging to study the mechanisms underlying immunotherapy and the tumor microenvironment. First, we will provide background on our current understanding of GBM, its immune microenvironment, as well as modern sequencing and imaging methods. Second, we will present a longitudinal study of GBM patients before and after treatment with PD-1 immunotherapy. Only a small fraction of GBM patients respond to this type of therapy, so we perform genomic, transcriptomic, and spatial analyses to compare the molecular features of these rare responders versus non-responders. We show that clinical response to PD-1 immunotherapy in GBM is associated with specific molecular alterations and immune infiltration profiles that reflect the tumor’s clonal evolution during treatment. The most common infiltrating immune cells in GBM are macrophages, which are implicated in a wide variety of pro-tumor and anti-tumor roles. We then focus on this specific immune population by analyzing single-cell expression data from GBM tumors. We identify a novel macrophage subpopulation characterized by expression of the scavenger receptor MARCO, which drives tumor progression in GBM and is altered over the course of PD-1 immunotherapy. Next, we demonstrate that the methods we have developed for GBM are applicable to understanding the tumor microenvironments of other cancers as well. We analyze a cohort of melanoma cases to show that transcriptomic and imaging features can be combined to create a biomarker that stratifies patients into different risk groups. Finally, while most of the image analysis described so far has utilized histopathology, we include two appendices where we demonstrate new ways to process and analyze Magnetic Resonance Imaging (MRI) in GBM.

The clinical manifestations, including variations, of the Stevens-Johnson syndrome (SJS) are reviewed. Lesions of the skin, eye, and mucous membranes are described and discussed. The potential complications and therapeutic approaches are outlined. Finally, the review discusses the controversy over the use of systemic corticosteroids in this syndrome.

No description available.

Yes / The cellular responses to two new temozolomide (TMZ) analogues, DP68 and DP86, acting against glioblastoma multiforme (GBM) cell lines and primary culture models are reported. Dose–response analysis of cultured GBM cells revealed that DP68 is more potent than DP86 and TMZ and that DP68 was effective even in cell lines resistant to TMZ. On the basis of a serial neurosphere assay, DP68 inhibits repopulation of these cultures at low concentrations. The efficacy of these compounds was independent of MGMT and MMR functions. DP68-induced interstrand DNA cross-links were demonstrated with H2O2-treated cells. Furthermore, DP68 induced a distinct cell–cycle arrest with accumulation of cells in S phase that is not observed for TMZ. Consistent with this biologic response, DP68 induces a strong DNA damage response, including phosphorylation of ATM, Chk1 and Chk2 kinases, KAP1, and histone variant H2AX. Suppression of FANCD2 expression or ATR expression/kinase activity enhanced antiglioblastoma effects of DP68. Initial pharmacokinetic analysis revealed rapid elimination of these drugs from serum. Collectively, these data demonstrate that DP68 is a novel and potent antiglioblastoma compound that circumvents TMZ resistance, likely as a result of its independence from MGMT and mismatch repair and its capacity to cross-link strands of DNA. / The full-text of this article was released for public view at the end of the publisher embargo on 2 Feb 2016.

O glioblastoma multiforme (GBM) é um dos gliomas mais comuns, classificado como um glioma de grau IV (Organização Mundial da Saúde - OMS) e notoriamente difícil de ser tratado. O tratamento recomendado consiste na ressecção cirúrgica seguida de radio e quimioterapia, e a sobrevida média dos pacientes é de apenas 12 meses após o diagnóstico. Portanto, novas terapias que focam a redução do volume do tumor e o aumento da morte das células tumorais são urgentemente necessárias. Estudos pré-clínicos sugerem que a inibição de COX-1 e 2 com Anti-inflamatórios não esteroidais (AINEs), como o Ibuprofeno (IBP), inibiram significantemente a proliferação e a migração celular em diferentes tumores. Assim, o presente estudo teve como objetivo avaliar in vitro o efeito da inibição de COX-1 e COX-2 através do tratamento com IBP, e também com inibidores específicos como SC-560 e NS-398 respectivamente, na migração e na proliferação da linhagem celular de glioma humano U251-MG. O presente estudo demonstrou através de diversos ensaios que a inibição de COX-1 e COX-2 através do IBP, do SC-560 e do NS-398 inibiu significativamente a migração e a proliferação celular da linhagem celular U251-MG. Dessa maneira, concluímos que a PGE2 está envolvida na migração e proliferação celular das células desta linhagem celular. / Glioblastoma Multiforme (GBM) is the most common glioma, classified as grade IV (World Health Organization WHO) and notoriously difficult to treat. The recommended treatment consists of surgery followed by radiotherapy and chemotherapy, and the median survival is ten to twelve months. Preclinical studies suggest that inhibiton of cyclooxygenase-2 by treatment with non-steroidal anti-inflammatory drugs, such as ibuprofen, significantly blocked the proliferation of different tumors including gliomas. Thus this study aimed to evaluate the migration of glioma cell line U251-MG after inhibition of cyclooxygenases 1 and 2 by treatment with ibuprofen (IBP), and specifics inhibitors such as SC-560 for COX-1 and NS-398 for COX-2. The present study demonstrated by various assays where inhibition of COX-1 and COX-2 by IBP, SC-560 and NS-398, significantly inhibited migration and cell proliferation of U251-MG cell line. Thus, we conclude that PGE2 is involved in this cell line migration and cell proliferation.

Les glioblastomes multiformes (GBM) comptent parmi les tumeurs au pronostic le plus sombre. L’extraordinaire capacité invasive des cellules tumorales rend toutes les interventions thérapeutiques actuelles totalement impuissantes. Une sous-population de Cellules Souches de Glioblastome (CSG) hautement invasive est responsable de la récurrence tumorale. Dans le cerveau, les GBM migrent principalement le long des vaisseaux sanguins au sein de l’espace périvasculaire riche en laminine, fibronectine et collagène ainsi qu’en suivant l’alignement des fibres myélinisées du corps calleux. La Matrice Extracellulaire (MEC) de ces régions joue un rôle important dans l’invasion des GBM, mais les mécanismes mis en jeu n’ont pas été complètement dévoilés. De plus, le développement de nouvelles thérapies anti-migratrices ciblant l’interaction des GBM avec la MEC reste encore limité. Dans le but de mimer la composition biochimique et les propriétés mécaniques de la MEC cérébrale et d’étudier leur rôle(s) dans la migration des CSG, nous avons développé un nouveau support de nanofibres (NF) alignées et fonctionnalisées avec de la laminine. Mes travaux de thèse ont montré que les NF génèrent un microenvironnement tridimensionnel (3D) favorisant l’adhésion et la migration des CSG. Cette adhésion est améliorée en comparaison avec les supports planaires (SP) conventionnels (2D) et récapitule mieux les mécanismes d’interaction des CSG avec la MEC au cours de l’invasion dans le modèle murin de tumeurs xénogreffées. Dans ces conditions physiologiques plus convenables générées par les NF, la variation des composantes biochimiques et mécaniques de la MEC affecte la migration des CSG. La présence ou l’absence de laminine régule le mode migratoire et l’orientation de fibres contrôle la direction de migration des CSG. D’un autre coté, l’altération de la glycosylation des protéines de la surface cellulaire module l’interaction des cellules tumorales du cerveau avec la MEC et augmente leur invasion. La deuxième partie de mes travaux de thèse a permis de démontrer que les glycomimétiques phostines « 3.1a » réorganisent le processus de la N-glycosylation des CSG diminuant leur invasivité in vitro et in vivo en inhibant les voies de signalisation de la kinase FAK et du récepteur de TGF-β impliqués dans l’interconnexion cellule-MEC. / Glioblastoma Multiforme (GBM) is a biologically aggressive tumor with an extremely poor prognosis. The highly invasive capacity of a subpopulation of Glioblastoma Initiating Cells (GIC) makes complete surgical resection impossible. GBM dissemination occurs along preexisting brain structures such as the perivascular space rich in laminin, fibronectine and collagen as well as the aligned myelinated fibers of the corpus callosum. The Extracellular Matrix (ECM) of these cerebral regions plays an important role during GBM invasion, but the underlying mechanisms remain largely unknown. Accordingly, the development of new anti-migratory therapies targeting the cell-ECM interactions is lacking. In order to mimic the compositional and physical properties of the cerebral ECM and to investigate their role(s) in GBM invasion, we have set up a new aligned nanofibers (NF)scaffold functionalized with laminin. My work demonstrated that the NFs constitute a tridimensional (3D) microenvironment supporting GIC adhesion and migration. The cell-ECM adhesion is improved on the NF in comparison to the conventional 2D planar surfaces (PS). Furthermore, the mechanisms of GIC interaction with the ECM on the NF are similar to those observed in the human GBM xenograft murine model. In this physiologically more relevant 3D microenvironment reproduced by the NF, the variation of the different biochemical and mechanical components of the ECM affects the migration of GIC. The presence or absence of laminin on the NF regulates the mode of migration and the orientation of the fibers dictates the direction of migration of GIC. On the other hand, the glycosylation that decorates cell surface proteins modulates the interaction of GBM tumor cells with the ECM and its alteration increases their invasion. The second part of my thesis demonstrated that the glycomimetics phostines « 3.1a » remodel the N-glycosylation of GIC and decrease their invasivity in vitro and in vivo via the inhibition of FAK and TGFβ-R signaling pathways known to be implicated in the cell-ECM intercommunication.

O glioblastoma multiforme (GBM) é um dos gliomas mais comuns, classificado como um glioma de grau IV (Organização Mundial da Saúde - OMS) e notoriamente difícil de ser tratado. O tratamento recomendado consiste na ressecção cirúrgica seguida de radio e quimioterapia, e a sobrevida média dos pacientes é de apenas 12 meses após o diagnóstico. Portanto, novas terapias que focam a redução do volume do tumor e o aumento da morte das células tumorais são urgentemente necessárias. Estudos pré-clínicos sugerem que a inibição de COX-1 e 2 com Anti-inflamatórios não esteroidais (AINEs), como o Ibuprofeno (IBP), inibiram significantemente a proliferação e a migração celular em diferentes tumores. Assim, o presente estudo teve como objetivo avaliar in vitro o efeito da inibição de COX-1 e COX-2 através do tratamento com IBP, e também com inibidores específicos como SC-560 e NS-398 respectivamente, na migração e na proliferação da linhagem celular de glioma humano U251-MG. O presente estudo demonstrou através de diversos ensaios que a inibição de COX-1 e COX-2 através do IBP, do SC-560 e do NS-398 inibiu significativamente a migração e a proliferação celular da linhagem celular U251-MG. Dessa maneira, concluímos que a PGE2 está envolvida na migração e proliferação celular das células desta linhagem celular. / Glioblastoma Multiforme (GBM) is the most common glioma, classified as grade IV (World Health Organization WHO) and notoriously difficult to treat. The recommended treatment consists of surgery followed by radiotherapy and chemotherapy, and the median survival is ten to twelve months. Preclinical studies suggest that inhibiton of cyclooxygenase-2 by treatment with non-steroidal anti-inflammatory drugs, such as ibuprofen, significantly blocked the proliferation of different tumors including gliomas. Thus this study aimed to evaluate the migration of glioma cell line U251-MG after inhibition of cyclooxygenases 1 and 2 by treatment with ibuprofen (IBP), and specifics inhibitors such as SC-560 for COX-1 and NS-398 for COX-2. The present study demonstrated by various assays where inhibition of COX-1 and COX-2 by IBP, SC-560 and NS-398, significantly inhibited migration and cell proliferation of U251-MG cell line. Thus, we conclude that PGE2 is involved in this cell line migration and cell proliferation.

Tyrimo metodai: Ląstelių sėjimo metodika; ląstelių tankio nustatymas; ląstelių gyvybingumo nustatymas MTT testu; neuronų žūties įvertinimas fluorescencinės mikroskopijos metodu; viduląstelinių RS kiekio įvertinimas; ekstraląstelinių RS kiekio įvertinimas; statistinė analizė. Tyrimo tikslas: Ištirti įvairių koncentracijų lektinų, išskirtų iš Phaseolus vulgaris L., antioksidacinį/ prooksidacinį poveikį ir įtaką C6 ląstelių gyvybingumui. Tyrimo uždaviniai: 1. Atlikti literatūros duomenų analizę apie lektinų, išskirtų iš Phaseolus vulgaris L., biologinį poveikį; 2. Nustatyti įvairių koncentracijų lektinų, išskirtų iš Phaseolus vulgaris L., antioksidacinį/prooksidacinį aktyvumą; 3. Nustatyti įvairių koncentracijų lektinų poveikį C6 ląstelių kultūros gyvybingumui. Tyrimų rezultatai: 1. Buvo matuojami vandenilio peroksido pokyčiai esant 1 - 10 µg lektino koncentracijoms ir nustatyta, kad skirtingų koncentracijų lektinas neveikia neutralizuojančiai vandenilio peroksido kiekio. 2. Atlikti vandenilio peroksido matavimai DMEM terpėje su 1 - 10 µg lektino koncentracijoms parodė, kad lektinas, priklausomai nuo jo koncentracijos, negeneruoja laisvųjų radikalų. 3. Buvo matuojamas glioblastomos C6 ląstelių gyvybingumas su MTT po 24 valandų ir nustatyta, kad didėjant lektino koncentracijai ląstelių gyvybingumas sparčiai mažėjo: 5 µg koncentracijos lektinas gyvybingumą sumažino beveik 2 kartus (iki 57,2111.16%), o 10 µg koncentracijos lektinas ląstelių gyvybingumą sumažino beveik 13... [toliau žr. visą tekstą] / Methods: The cell cultivation method; measurement of cell density; determination of cell viability with MTT assay; assessment of neuronal death with fluorescent microscopy; measurement of intracellular RS; measurement of extracellular RS; statistical analysis. The aim of research: To investigate antioxidative/prooxidative effects of different concentrations of the lectin, isolated from Phaseolus vulgaris L., and influence on the viability of the C6 cells. Goals of the study: 1. To perform an analysis of the literature on the biological effects of lectin, isolated from Phaseolus vulgaris L.; 2. To determine antioxidative/prooxidative activity of different concentrations of the lectin, isolated from Phaseolus vulgaris L.; 3. To determine effect on viability of the C6 cell culture using different concentrations. Results: 1. Concentrations of hydrogen peroxide were measured with 1 - 10 µg concentrations of lectin and it was found, that different concentrations of lectin did not neutralize hydrogen peroxide. 2. Measurements of hydrogen peroxide in DMEM medium with 1-10 mg concentrations of lectin showed, that the lectin, depending on it's concentration, did not generate free radicals. 3. Viability of cells was measured in C6 glioblastoma cells with MTT after 24 hours and it was found, that when concentration of lectin increased, viability of cells rapidly decreased: 5 µg concentration of lectin reduced the viability of almost 2 times ( up to 57.21% ± 11.16% ) and at 10 µg... [to full text]