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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
331

The Role of Fire Disturbance in the Invasion of South Florida

Stevens, Jens 11 September 2008 (has links)
Abstract Exotic plant species may facilitate their invasion into native communities through the modification of ecosystem disturbances such as fire regimes. Where frequent fires are common, invasive plants that suppress fire may induce a positive feedback which further suppresses fire and promotes their continued invasion. In the pine rockland savanna ecosystem of south Florida, the frequent understory fire regime may be altered by the fire-resistant invasive shrub Brazilian pepper (Schinus terebinthifolius). In this thesis, I document the interaction of Brazilian pepper and fire in these savannas. I show that fire causes significant (30%-50%) mortality among low-density populations of Brazilian pepper. However, Brazilian pepper exhibits rapid growth and reproduces quickly following fire, and in the absence of fire it has a low mortality rate. Furthermore, Brazilian pepper can cause a reduction in fire temperature from 47° C at low densities, to almost 200° C at high densities, where it can completely impede fire spread. This creates the potential for Brazilian pepper to initiate a fire-suppressing feedback if it can reach a density threshold during extended fire-free intervals. At a landscape scale, I analyzed digital aerial photographs to show that fire frequency correlates with the extent of Brazilian pepper invasion into pine savanna fragments in southern Florida. In savannas where fire is frequent, Brazilian pepper does not heavily invade, but savannas that are heavily invaded tend to be unburned for more than 20 years. This supports both the regulation of low-density Brazilian pepper populations by fire, and the potential for high-density Brazilian pepper populations to suppress fire and facilitate further invasion.
332

FUNCTION AND REGULATION OF MATRIX METALLOPROTEINASE-1 IN GLIOBLASTOMA MULTIFORME

Anand, Monika 29 July 2010 (has links)
Glioblastoma Multiforme (GBM) is an aggressive and fatal cancer of the brain. It is characterized with augmented morbidity and elusion to therapies due in part to the incessant infiltration and spread of tumor cells in normal brain. We investigated the function of Matrix metalloproteinase-1, an important enzyme noted to be responsible for invasion in other cancers, in GBM and its regulation by epidermal growth factor receptor (EGFR) signaling. Previous studies from our laboratory demonstrated elevated levels of MMP-1 in GBM. Further studies indicated the involvement of MMP-1 in GBM invasion. The GBM cell lines T98G, U251MG and U87MG were used for this study. In T98G cell lines, inhibition of MMP-1 by siRNA significantly suppressed basal in vitro invasion without impacting cell viability. The over-expression of MMP-1 was accomplished in U251MG and U87MG using the mammalian expression vector, pIRES, encoding full length MMP-1 cDNA. The MMP-1 over-expressing U251MG and U87MG cells exhibited significantly enhanced invasion in vitro with no modification in the cell proliferation rates. A majority of GBM patients present defective EGFR signaling due to over-expression, amplification or mutation in the receptor. MMP-1 is known to be up-regulated by various stimulatory agents including growth factors. We examined the regulation of MMP-1 by EGFR activation and observed the induction of MMP-1 after EGF treatment. Inhibition of the receptor by pharmaceutic inhibitor treatment and genetic approaches led to reduction in MMP-1 levels. We also observed that this regulation is primarily mediated by the downstream MAPK pathway. Inhibition of MAPK and not PI3K pathway resulted in diminished MMP-1 protein levels even in the presence of EGF. These studies demonstrate the importance of the EGFR-MAPK signaling pathway in the induction of MMP-1 in glioma cell lines. In addition, MMP-1 plays a role in glioma cell invasion in vitro. These results along with the reports of MMP-1 over-expression in GBM warrant future studies examining the function of MMP-1 in vivo.
333

Anaplasma phagocytophilum remodels its host cell-derived vacuole into a protective niche by redecorating the vacuolar membrane with select Rab GTPases and bacterial proteins

Huang, Bernice 11 November 2011 (has links)
Anaplasma phagocytophilum is an obligate intracellular bacterium that infects neutrophils to cause the emerging tick-transmitted disease, human granulocytic anaplasmosis (HGA). Following entry, the pathogen replicates within a host cell-derived vacuole that fails to mature along the endocytic pathway, does not acidify, and does not fuse with lysosomes. Selective fusogenicity is prototypical of many vacuole-adapted pathogens and has been attributed, at least in part, to pathogen modification of the vacuolar inclusion membrane and/or to selective recruitment or exclusion of host trafficking regulators. As a result, the A. phagocytophilum-occupied vacuolar membrane (AVM) provides a unique interface to study the host-pathogen interactions critical to A. phagocytophilum intracellular survival. Diverse vacuole-adapted pathogens; including Chlamydia, Legionella, and Salmonella; selectively recruit host Rab GTPases to their vacuolar membranes to establish replicative permissive niches within their host cells. Rab GTPases coordinate many aspects of endocytic and exocytic cargo delivery. We determined that the A. phagocytophilum-occupied vacuole (ApV) selectively recruits a subset of fluorescently-tagged Rabs that are predominantly associated with recycling endosomes. Another emerging theme among vacuole-adapted pathogens is the ability to hijack ubiquitin machinery to modulate host cellular processes. Mono- and polyubiquitination differentially dictate the subcellular localization, activity, and fate of protein substrates. Monoubiquitination directs membrane traffic from the plasma membrane to the endosome and has been shown to promote autophagy. We show that monoubiquitinated proteins decorate the AVM during infection of promyelocytic HL-60 cells, endothelial RF/6A cells, and to a lesser extent, embryonic tick ISE6 cells. Importantly, tetracycline treatment concomitantly promotes loss of the recycling endosome-associated GFP-Rabs and ubiquitinated proteins and acquisition of the late endosomal marker, Rab7, and lysosomal marker, LAMP-1, implicating bacterial-derived proteins in the ApV's altered fusogenicity. Therefore, we rationalized that A. phagocytophilum-encoded proteins that associate with the AVM may establish interactions with the host cell that are important for intracellular survival. By focusing on A. phagocytophilum proteins that are induced during host infection, we identified the first two bacterial-encoded proteins -- APH_1387 and APH_0032 -- that modify the AVM. Although functional studies are hindered by the lack of a system to genetically manipulate Anaplasma, the pathobiological roles of APH_1387 and APH_0032 are likely unique, as both proteins exhibit very little or no homology with any previously described protein. APH_1387 and APH_0032 are present at the cytoplasmic face of the AVM, therefore they likely interact with host proteins. We demonstrate that ectopic expression of APH_1387 and APH_0032 inhibits the ApV development in A. phagocytophilum infected cells. The results presented in this dissertation contribute to our understanding of how A. phagocytophilum modifies the vacuolar membrane in which it resides to establish a safe haven and evade lysosomal degradation.
334

Caractérisation de lésions tumorales par imagerie spectrale infrarouge associée à la biométrie floue

Sebiskveradze, David 29 June 2011 (has links)
En oncologie, l’anatomopathologie est le « gold standard » pour le diagnostic et l’évaluationpronostique de lésions tumorales à l’échelle tissulaire. Depuis peu, les spectroscopiesvibrationnelles, notamment IR, représentent des axes de développement prometteurs pour cettespécialité en ouvrant la voie à l’histologie spectrale. Bien que « la preuve de concept » de cettedémarche soit maintenant réalisée, il reste encore de nombreux points à traiter avant un transfertvers la clinique. Dans ce travail, nous nous sommes intéressés à deux d’entre eux, impliqués dans lavitesse d’obtention, la qualité et le contenu informatif des images spectrales ; à savoir ledéparaffinage numérique des coupes tissulaires et la construction automatique et non supervisée deces images par biométrie floue. Afin de s’affranchir du déparaffinage chimique, nous avons montréque comparativement à l’ICA-NCLS, la méthode de prétraitement des spectres IR par EMSCs’avère la plus adaptée à l’élimination de la signature spectrale de la paraffine. Cette étape permetdonc l’utilisation directe de coupes tissulaires conventionnelles en histologie spectrale et rendpossible des études rétrospectives. La construction d’images spectrales capables de révéler les zonestumorales et les différentes structures tissulaires nécessite des méthodes performantes declassification des données IR. Basé sur la classification floue (FCM, Fuzzy C-Means), nous avonsmis au point un algorithme permettant d’optimiser le nombre de classes K et le paramètre de flou mde façon automatique et simultanée. L’algorithme a été testé au niveau de différents types decancers cutanés comme des carcinomes basocellulaires (BCC), spinocellulaires (SCC), maladies deBowen et mélanomes et comparé aux classifications « dures », comme le K-means (KM) etl’analyse par classification hiérarchique (ACH). Les images FCM révèlent une forte hétérogénéitéintra-tumorale pour les BCC, SCC et mélanomes et permettent de mieux caractériserl’interconnectivité entre les structures tissulaires saines et tumorales. De plus, pour certainestumeurs infiltrantes comme les SCC, un front d’invasion tumoral est mis en évidence ainsi que sesconnexions avec le tissu environnant. En conclusion, l’ensemble de ces résultats souligne le fortpotentiel de l’association microspectroscopie IR/biométrie floue pour la caractérisation de lésionstumorales / In oncology, anatomical pathology is the "gold standard" for diagnosis and prognostic evaluation of tumor lesions on a tissue scale. Since recently, vibrational spectroscopies, especially IR spectroscopy, represent promising guidelines of development for this specialty paving the way for spectral histology. Although "proof of concept" of this approach is now done, there are still many issues before its transfer into the clinic. In this study we focused on two important issues, namely digital dewaxing of the paraffin-embedded tissue sections, and automatic and unsupervised construction of spectral images by fuzzy biometric methods, which are rapid and provide high quality content spectral information.In order to overcome the chemical dewaxing, we have shown that compared to the ICA-NCLS, the IR spectra preprocessing method by EMSC is better for the elimination of paraffin spectral signature. This step thus allows the direct use of conventional tissue sections in spectral histology and enables retrospective studies. The construction of spectral images which reveal tumor areas and the different tissue structures requires efficient methods of IR data clustering. Based on the fuzzy clustering (FCM, Fuzzy C-Means), we developed an algorithm permitting to automatically and simultaneously optimize the number of clusters K and the fuzzy parameter m. This algorithm was applied to different types of skin cancers such as basal cell carcinomas (BCC), squamous cell carcinomas (SCC), Bowen's diseases and melanomas and compared with the "hard" clustering methods as K-means (KM) and Analysis by Hierarchical Clustering (AHC). The FCM images reveal strong intratumoral heterogeneity for BCC, SCC and melanomas and allow better characterization of the interconnectivity between the tumor and healthy tissue structures. In addition, for some invasive tumors such as SCC, a tumor invasive front is highlighted as well as its connections with the surrounding tissue. In conclusion, all these results highlight the potential of the IR microspectroscopy/fuzzy biometric methods association for characterization of tumor lesions.
335

Poslední vojenská diktatura v Argentině v letech 1976 - 1983 / The last military dictatorship in Argentina in the years 1976 - 1983

Rosenkrancová, Eva January 2014 (has links)
(in English) The thesis discusses the government of the most recent military dictatorship in Argentina in 1976-1983. The first chapter defines the basic concepts that are important for the proper interpretation of the work and provides a brief overview of the political developments and the situation in the country in the 20th century that preceded the last military coup. The main part of the thesis gives the characteristics of the period 1976-1983, that is rise to power, action and fall of the military dictatorship with a reflection of the development of relations with the USA and Argentina in this period of time. It also delivers a view of the Falklands War, which accelerated the transition from dictatorship to democracy in Argentina. The work also includes insight into the present in the context of the impact of the seven-year military junta to Argentine society as well as the question of the future of the islands, in the context of the continuing recognition of Argentina's claims to sovereignty over the islands.
336

Invasion potential and colonization dynamics of Fusarium proliferatum

Reyes Gaige, Andres Jose January 1900 (has links)
Doctor of Philosophy / Department of Plant Pathology / James Stack / The trade of food, plant, and animal products has increased the worldwide movement and establishment of exotic pathogens with dramatic negative impacts on plant systems. Fusarium proliferatum is a broad host-range pathogen and among the most common maize pathogens globally. It is often seed-borne and symptomless in maize, making it a high risk for introduction in maize and other grains. Considering the global distribution of maize and the wide host range and production of mycotoxins by F. proliferatum, a better understanding of its life history is needed. To provide markers for tracking F. proliferatum in laboratory experiments, strains of F. proliferatum were transformed to express a green fluorescent protein (GFP). Active dispersal (at least 1.5cm at 25°C and -50mb soil matric potential) and colonization of organic matter in nonsterile field soil was demonstrated in soil microcosms. Fusarium verticillioides is commonly isolated from maize seed also colonized by F. proliferatum. A red fluorescent (mRFP) F. verticillioides transformant was developed to study competition with F. proliferatum. For quantification in host tissues, a TaqMan multiplex qPCR protocol was developed using primer and probe sets targeting fragments of the green and red fluorescence genes to detect F. proliferatum and F. verticillioides, respectively. Prior colonization of maize tissues by F. verticillioides (p=0.6749) and other seed-borne microorganisms (p=0.1910) did not affect subsequent colonization by F. proliferatum. Genotyping-by-sequencing (GBS) was used to identify genetic markers in F. proliferatum. Primer sets based GBS markers were designed to allow detection of specific isolates in field experiments. F. proliferatum populations were characterized from maize seed prior to planting and again after harvest. End-point PCR identified F. proliferatum isolates containing the GBS marker. AFLP-fingerprinting indicated that 23 of the 817 F. proliferatum isolates contained the molecular marker and were genetically related to the original isolate. Based on the subclade and percentage similarity in UPGMA phylogenetic trees, and the population grouping observed in STRUCTURE and Principal Coordinate Analysis, these isolates could have a single origin and be clonal. Understanding the life cycle of F. proliferatum is critical for learning more about the risk of introducing seed-borne exotic isolates into new environments.
337

Prévention de la migration radio-induite des cellules cancéreuses du sein

Bouchard, Gina January 2016 (has links)
Le cancer du sein triple négatif (TNBC) représente entre 15-20% des cancers du sein et est l'un des types les plus agressifs. De plus, un sous-groupe de ces patientes est résistant à la radiothérapie (RT) et développe fréquemment une récidive hâtive de la maladie. Des études précédentes ont démontré que l’inflammation induite par la RT accélère la progression du cancer et le développement des métastases. Cette hypothèse a donc été validée dans un modèle pré-clinique de TNBC en implantant les cellules de carcinome de souris triple négatives D2A1 dans les glandes mammaires de la souris Balb/c. Premièrement, la tumeur primaire à été irradiée à une dose sous-curative une semaine post-implantation des cellules. En deuxième lieu, le tissu mammaire de la souris a été pré-irradié avant d'implanter les cellules cancéreuses afin de bien discerner l'effet du microenvironnement irradié sur celles-ci. Ces deux modèles ont mené à une augmentation significative des cellules tumorales circulantes ainsi que du nombre de métastases pulmonaires. Plusieurs molécules inflammatoires dont l'interleukine-1 bêta (IL-1β), l'interleukine-6 (IL-6) ou encore la cyclooxygénase 2 (COX-2) ont été identifiées comme facteurs clés impliqués dans la migration radio-induite des cellules cancéreuses du sein. Conséquemment, un inhibiteur large-spectre comme la chloroquine (CQ), entre autres utilisé comme traitement anti-malarien et anti-inflammatoire, a su prévenir ces effets secondaires associés à la RT. Étant donné que l'action de la CQ est peu sélective, une répression de l'expression de l'ARNm de la métalloprotéinase (MMP) de membrane de type 1 (MT1-MMP), une MMP de surface impliquée notamment dans la migration cellulaire, l'invasion tumorale et l'angiogenèse, a été réalisée afin d'éclaircir le mécanisme d'inhibition des métastases radio-induites. Cette répression de la MT1-MMP prévient la formation des métastases pulmonaires radio-induites, démontrant ainsi un des mécanisme important de l'invasion radio-induite. Ce résultat confirme donc l'importance de la MT1-MMP dans ce phénomène et son potentiel comme biomarqueur de prédiction de l'efficacité des traitements de RT, particulièrement chez les patientes atteintes de TNBC.
338

Privacy invasions and their association with poor parent-adolescent relationship

Adan, Farhiya, Schibort, Olivia January 2019 (has links)
In this study we examine whether privacy invasions are associatedwith poor parent-adolescent relationship. We also examined if therewere differences between mothers and fathers in the frequency oftheir invasions, as well as the intent of those invasions. Lastly, welooked at associations between privacy invasions and parentadolescentrelationships and if these were modified by parent oradolescent gender. We hypothesized that intentional and frequentprivacy invasions would have a stronger association with poorparent-adolescent relationship than accidental and infrequentinvasions of privacy. The data for this study was selected from alarger database. Participants consisted of 78 adolescents, 39 girlsand 39 boys. Data were collected through questionnaires that bothadolescent and parent answered separately. The adolescents filledout the questionnaires at school in different classrooms. Weconcluded that frequent privacy invasions had a significantassociation with poor parent-adolescent relationship for mothers,but not fathers. Furthermore, the interaction between the frequencyof privacy invasions and the intent was significant for mattering tomothers. However, no significant relations were found for fathers. / I den här studien undersöker vi huruvida integritets-inkräktande ärförknippade med dålig förälder-ungdom relation. Vi undersökteockså om det fanns skillnader mellan mammor och pappor ifrekvensen av deras invasioner, liksom avsikten med dessainvasioner. Slutligen såg vi på associationer mellan integritetsinkräktandeoch föräldra-ungdoms relationer och om dessamodifierades av föräldrar eller ungdomars kön. Vi förutsåg attavsiktligt och frekvent integritets-inkräktande skulle ha en starkareförknippning med dålig förälder-ungdom relationer än oavsiktligaoch sällsynta invasioner av integritet. Uppgifter för denna studievaldes från en större databas. Deltagarna i studien bestod av 78ungdomar, 39 flickor och 39 pojkar. Uppgifterna samlades ingenom flera frågeformulär som både ungdomar och föräldrarbesvarade separat. Ungdomarna fick besvara frågeformulären iskolan i olika klassrum. Slutsatsen var att mängden integritetsinskränkandefaktiskt hade en signifikant koppling med dåligförälder-ungdom relation för mödrar, men inte för fäder. Äveninteraktionen mellan mängden integritetskränkande och derasavsikt visade sig vara signifikant för mödrar. Dock fanns ingensignifikant relation för fäder.
339

Munícipes e escabinos: poder local e guerra de restauração no Brasil holandês (1630-1654) / Residents and escabinos: local and war restoration in Dutch Brazil

Luciani, Fernanda Trindade 24 January 2008 (has links)
Este trabalho investiga as formas de organização do poder local durante os 24 anos em que os neerlandeses dominaram as capitanias do Norte do Estado do Brasil (1630-1654). Como ao longo de tal período não se verifica uma continuidade na administração local, a investigação teve em vista a compreensão da estrutura e da dinâmica política das Câmaras Municipais da legislação portuguesa, que perduraram até o ano de 1637, assim como das Câmaras de Escabinos (Kamers van Schepenen), que foram criadas conforme previam as instruções da República das Províncias Unidas, contribuindo, assim, para o estudo das diferentes formas de administração local no Brasil Colônia. Nosso objetivo mais além, ao abordar como tal transformação no poder local foi sentida pela elite açucareira e pelos moradores das capitanias conquistadas, relacionando esse contexto ao da reação luso-brasileira contra os invasores a partir de 1645, destacando, então, o papel que as Câmaras Municipais exerceram nesse período de guerra de Restauração (1645-1654). Para tanto, nossa pesquisa insere-se em discussões mais amplas e críticas sobre, por um lado, administração e poder no Império Português, sobretudo no que se refere às relações entre os poderes locais coloniais e o poder central da metrópole, e, por outro, a expansão comercial e territorial dos Países Baixos por meio de suas companhias de comércio no século XVII. Partindo da análise do poder local no Brasil Holandês entendemos ser possível pensar os diferentes sistemas de dominação colonial, o português e o neerlandês, que se confrontaram nesse período e território. / This work researches the organizational forms of local government in the 24 years of Dutch domination over the northern Estado do Brasil (1630-1654). As on the course of that period there was no stability in local government, this investigation has in sight an understanding of the structure and political dynamics both of the Portuguese Municipal Councils (Câmaras Municipais), which lasted until the year 1637, and of the Councils of Schepens (Kamers van Schepenen or Câmaras de Escabinos), created according to the instructions established by the Dutch Republic, and thus contributing to the study of the different forms of local government in colonial Brazil. Our aim is to go further by treating how that transformation in local government was felt by sugar aristocracy and by the inhabitants of the dominated captaincies, relating this context to the one of a luso-brazilian reaction against the invaders after 1645, and then attending to the role played by the Municipal Councils in the war of Restoration period (1645-1654). In that, our research falls in a larger and more critical debate about, in one hand, both government and rule in the Portuguese Empire, especially in which refers to the relationship between colonial local government and the central metropolitan government, and in the other, commercial and territorial expansion of the Lower Countries through their commercial companies in the seventh century. From the analyses of local government in Dutch Brazil it is possible to question the differing systems of colonial domination, both Portuguese and Dutch, which confronted each other in this time and period.
340

Amilóide Sérica A (SAA) e câncer: efeitos biológicos e mecanismos de ação em glioblastomas multiformes / Serum amyloid A (SAA) and cancer: biological effects and mechanisms of action in glioblastomas multiformes

Knebel, Franciele Hinterholz 30 September 2014 (has links)
Células tumorais têm sua proliferação e mobilidade modificada por diversos fatores de crescimento, citocinas e mediadores inflamatórios, dentre os quais a amilóide sérica A (SAA). Estudos prévios do nosso grupo mostraram o efeito direto da SAA em processos de proliferação, migração e invasão de células de glioblastoma multiforme (GBM), A172 e T98G. Neste estudo nós complementamos resultados prévios de migração e invasão; avaliamos SAA como possível indutora de moléculas importantes para a invasividade do tumor, como as MMP-2 e -9 e ROS; realizamos ensaio clonogênico com a intenção de investigar uma possível contribuição da rSAA no estágio inicial de desenvolvimento do tumor; avaliamos o impacto da hipóxia na expressão dos diferente genes da SAA; estimulamos as células com indutores hepáticos clássicos da SAA e analisamos a possibilidade destes induzirem os diferentes genes da SAA em células tumorais; avaliamos possíveis receptores e vias de sinalizações envolvidas nos processos de proliferação, migração e invasão. Construímos knockdowns (KDs) dos genes da SAA de fase aguda (SAA1 e 2) e constitutiva (SAA4) e avaliamos a função de cada um deles para a morfologia e para os processos de proliferação, migração e invasão de GBM. Por fim investigamos SAA como possível biomarcadora de gliomas em amostras clínicas. Nossos resultados sugerem que rSAA afetou a atividade das MMP-2 e -9 e a produção de ROS em ambos GBM, mas não se mostrou clonogênica. As citocinas IL-6, TNF-α e IL-1β, mas não a hipóxia, foram capazes de induzir os diferentes genes da SAA. A adição de rSAA às culturas celulares estimulou a transrição dos diferentes genes da SAA, sugerindo a ativação de mecanismos intracelulares retroalimentados. Efeitos pró-tumorais da rSAA parecem ser viabilizados via RAGE, enquanto efeitos anti-tumorais parecem ser induzidos via TLR-4. Pela primeira vez mostramos que SAA induz aumento de RAGE. KDs da SAA inibiram proliferação, migração e invasão, sugerindo que SAA seja um produto tumoral importante para a manutenção do fenótipo invasivo de GBM. A adição de SAA exógena reverteu grande parte dos efeitos nas células T98G KD, enquanto células A172 KD responderam parcialmente à rSAA. KDs da SAA sugerem a mesma como mantenedora da morfologia das células de GBM. De maneira inédita mostramos que o gene SAA4 até então descrito como um gene constitutivo de função desconhecida é importante para a proliferação, migração e invasão de GBM. Nós especulamos que os efeitos diferenciados induzidos por rSAA nos GBM estejam associados à natureza multiligante da SAA e às diferenças genéticas dos GBM. Pacientes com GBM apresentaram aumento significativo na transcrição e expressão de SAA1 no tecido tumoral, bem como aumento sérico de SAA. A correlação na expressão de SAA1 com moléculas importantes para progressão tumoral, como CXCR4, CXCR7, CD163 e HIF-1α também a identificam como uma proteína associada à malignidade. / Tumor cells have their proliferation and migration modified by several growth factors, cytokines and inflammatory mediators, such as serum amyloid A (SAA). Previous studies from our group showed the direct effect of SAA on proliferation, migration and invasion of glioblastoma multiforme (GBM) cells, A172 and T98G. In this study we complemented previous migration and invasion data; evaluated SAA as possible inducer of MMP-2, -9 and ROS; performed clonogenic assay to investigate a possible contribution of rSAA in the early stage of tumor development; evaluated the impact of hypoxia on the expression of different genes of SAA; stimulated the cells with classics inducers of hepatic SAA and analyzed the possibility of these different genes to induce SAA in tumor cells; evaluated possible receptors and signaling pathways involved in proliferation, migration and invasion processes. SAA knockdowns (KDs) were made for acute phase (SAA1 and 2) and constitutive protein (SAA4) and evaluated their role in cell proliferation, migration, morfology and invasion. Finally it was investigated SAA as a possible biomarker of glioma grade in clinical samples. Our results suggest that rSAA affects MMP-2 and -9 activity and ROS production in both GBM, but did not affect clonogenicity. IL-6, TNF-α and IL-1β, but not hypoxia, were able to induce SAA expression. rSAA addition to cell cultures stimulated transcription of the three different SAA genes, suggesting the activation of intracellular feedback mechanisms. Pro-tumor effects of rSAA seem to occur via RAGE and anti-tumor effects appear to be induced via TLR-4. This was de first time that induction of RAGE triggered by rSAA was shown. Proliferation, migration and invasion were inhibited in SAA KDs, suggesting that SAA is an important tumoral product for the maintenance of the invasive phenotype of GBM. The addition of exogenous SAA largely reversed the effects on SAA KDs T98G cells, whereas SAA KDs A172 cells partially responded to the rSAA. The findings with SAA KDs suggest that SAA affect cell morphology. Another new contribution from our study was that SAA4, a constitutive gene with unknown function, was important for the proliferation, migration and invasion of GBM and it can be induced by rSAA, IL-6, TNF-α and IL-1β. We speculate that the different effects induced by rSAA in GBM are associated with the affinity of SAA to different receptors and the different genetic backgrounds of GBM. Patients with GBM showed a significant increase in the transcription and expression of SAA1 in tumor tissue as well as increased serum SAA. The correlation between the expression of SAA1 with important molecules for tumor progression, such as CXCR4, CXCR7, CD163 and HIF-1α also identified SAA as a protein associated with malignancy.

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