Made available in DSpace on 2014-08-20T14:30:10Z (GMT). No. of bitstreams: 1 Dissertacao_alessandro_menna_alves.pdf: 813449 bytes, checksum: 43f43131b0d8e54633d172ea87ffa722 (MD5) Previous issue date: 2013-03-18 / This dissertation was divided into two distinct works, which can be summarized as follows: Article 1: The oral squamous cell carcinoma (OSCC) is the most prevalent malignance in mouth, being an important public health problem. The aim of this study was to evaluate the clinical and epidemiological profile of the OSCC cases registered in a center of clinical and histopathological diagnosis, located in Southern Brazil. Eight hundred and six individuals with OSCC and its variants were included in this study, over 1959-2012 period. The variables recorded from the files were: age, gender, skin color, tumor location, size and evolution time of the lesions (referred by the patients), as well as, the presence of pain lymph nodes, habits of tobacco and alcohol, and also the profession. OSSC was more frequent in males (76.6%), with the majority of cases distributed between 51 and 70 years old (53.9%). The most prevalent sites were lower lip vermilion [23.3% (20.4; 26.4)], followed by lateral border/ventral surface of the tongue [20.2% (17.5; 23.2)], gingiva/alveolar ridge [18.1% (15.5; 21.0)], and floor of the mouth [14.9% (12.5; 17.5)]. A strong association between outdoor occupation and OSCC in lower lip vermilion was found. The OSCC lesions located in tongue, gingiva/alveolar ridge and floor of the mouth were commonly more painful, bigger than 2 cm, and frequently presenting lymph nodes involvement. Most of the results confirm the data from literature. Mouth self-examination should be recommended and campaigns of prevention and early detection of OSCC should be periodically performed in order to increase people s feelings of personal risk. Article 2: Inside the tumor microenvironment (TM) the neoplastic cells are in dynamic crosstalk with the vascular and lymphatic endothelial cells in order to allow the tumor to growth and metastasize. Hypothesizing that there is a crosstalk between lymphatic endothelial cells and tumor cells from squamous cell carcinoma (SCC) that plays an important role in metastasis, we aimed to identify potential interactions between lymphatic endothelial cells and tumor cells lines from SCCs, through some in vitro assays. Primary adult human dermal lymphatic microvascular endothelial cells (HMVECs) and the human head and neck SCC cell lines like A431, UM-SCC-1, UM-SCC-22A and UM-SCC-22B were cultured in their specific media. UM-SCC cells lines were treated with rhIL-6, being VEGF-C expression checked by Elisa. Baseline IL-6 was evaluated in HMEVCs using the same assay. Also the IL-6 receptor (IL-6R) was analyzed by Western blot in UM-SCC cells. Conditioned media from HMVECs were prepared with different treatments and incubated with SCC A431 cells, in order to verify the MMPs enzymatic activities by gelatin zymography. Our results demonstrated that there are interactions between tumor cells and LECs, since the LECs-CM were able to enhance MMP-2 gelatinolytic activity. Moreover, we showed that LECs secrete IL-6, and different SCC lines have receptors for this cytokine. Therefore, our results indicate some potential interactions between LECs and TCs, being necessary other studies to elucidate the involved signaling pathways / Esta dissertação foi dividida em dois trabalhos distintos, os quais podem ser resumidos da seguinte maneira: Artigo 1: O carcinoma espinocelular oral (CEO) é o tumor maligno mais prevalente na cavidade oral, sendo um importante problema de saúde pública. O objetivo deste estudo foi avaliar o perfil clínico e epidemiológico dos casos registrados de CEO em um centro de diagnóstico clínico e histopatológico, localizado no Sul do Brasil. Oitocentos e seis indivíduos com CEO e suas variantes histológicas foram incluídos neste estudo, num período entre 1959 e 2012. As variáveis anotadas dos arquivos foram: idade, sexo, cor da pele, sítio, tamanho, tempo de evolução (relatado pelo paciente), assim como a presença de dor, linfonodos palpáveis, hábitos de tabagismo e etilismo, e a profissão. CEO foi mais prevalente em homens (76,6%), com a maioria dos casos distribuídos entre os 51 e 70 anos de idade (53,9%). Os sítios mais prevalentes foram vermelhão do lábio inferior [23,3% (20,4; 26,4)], seguido por borda lateral/ventre de língua [20,2% (17,5; 23,2)], gengiva/rebordo alveolar [18,1% (15,5; 21,0)], e assoalho bucal [14,9% (12,5; 17,5)]. Foi encontrada uma forte associação entre ocupações ao ar livre e CEO de vermelhão de lábio inferior. As lesões localizadas na língua, gengiva/rebordo alveolar e assoalho bucal foram comumente mais dolorosas, maiores que 2 cm, a frequentemente apresentavam envolvimento de linfonodos. A maioria dos nossos resultados confirmam os dados da literatura. O autoexame bucal deveria ser recomendado e campanhas de prevenção e detecção precoce do CEO deveriam ser realizadas periodicamente na tentativa de aumentar o sentimento pessoal em relação ao CEO. Artigo 2: Dentro do microambiente tumoral (MT), as células neoplásicas estão numa constante crosstalk com células endoteliais linfáticas (CELs) e sanguíneas a fim de permitir o crescimento tumoral e metástase. Supondo que haja um crosstalk entre as CELs e as células do carcinoma espinocelular (CE) que exerce um importante papel na metástase, nosso objetivo foi identificar potenciais interações entre as CELs e linhagens celulares de CE, através de alguns ensaios in vitro. Células endoteliais linfáticas primárias adultas humanas da microvasculatura dérmica (HMVECs) e as linhagens de CE A431, UM-SCC-1, UM-SCC-22A e UM-SCC-22B foram cultivadas nos seus meios específicos. UM-SCC foram tratadas com rhIL-6, sendo a expressão de VEGF-C verificada por Elisa. Produção natural de IL-6 pelas HMVECs foi avaliada da mesma maneira. A presença de receptor de IL-6 (IL-6R) foi analisada por Western Blot nas linhagens UM-SCC. Meios condicionados(MC) das HMVECs foram preparados com diferentes tratamentos e incubados com a linhagem A431, a fim de verificar a atividade genatinolítica das MMPs por zimografia. Nossos resultados demonstraram que há interações entre as células tumorais e as CELs, uma vez que MC-CELS foram capazes de aumentar a atividade genatinolítica da MMP-2. Além disso, nós mostramos que as CELs secretam IL-6, e diferentes linhagens de CE possuem receptores para esta citocina. Sendo assim, nossos resultados indicam potenciais interações entre as LECs e as células tumorais, sendo necessário outros estudos para elucidar as vias de sinalização envolvidas

Les métastases sont la principale cause de décès chez les patients atteints d’un cancer. Lors du développement métastatique, les cellules tumorales disséminées (CTD) doivent franchir certaines étapes clés avant de coloniser des organes distants de la tumeur primaire. Notre hypothèse est que la TNC pourrait jouer différents rôles dans la migration des cellules cancéreuses et par conséquent dans le développement métastatique. Considérant l’actine comme un réservoir de facteurs de croissance, la TNC pourrait induire la TEM ainsi que la survie et l’extravasation des cellules tumorales. Cependant, des cellules cancéreuses individualisées localement pourraient répondre à la TNC en initiant des changements rapides menant à un phénotype migratoire de type amiboïde. L’objectif de cette thèse a été d’étudier comment la TNC stimule le développement métastatique dans le cancer du sein au niveau cellulaire et moléculaire en utilisant des modèles tumoraux et cellulaires. / A high TNC expression correlates with lung metastagenicity and was shown to promote experimental lung metastasis, but the underlying mechanisms are poorly understood. The results of my thesis have provided insight into the roles of TNC in metastasis suggesting that TNC contributes to extravasation by impacting on survival, endothelialization, EMT and migration. Moreover, I have identified TGF-β signaling and integrin α9β1 as important pathway and molecule, respectively to be employed by TNC. Whether both molecule/pathway play a similar role in the investigated models of breast cancer, osteosarcoma and glioblastoma remains to be seen.

Le glioblastome (GBM) est la forme de cancer du cerveau la plus courante et la plus meurtrière. Sa nature diffusive entraine une impossibilité d’élimination complète par chirurgie. Une récidive de la tumeur chez ≥ 90% des patients peut être provoqué par des cellules GBM résiduelles se trouvant près du bord de la cavité de résection. Un implant pouvant libérer de manière durable la protéine SDF-1α, qui se lie aux récepteur CXCR4 à la surface des cellules GBM, peut être utile pour induire le recrutement des cellules GBM résiduelles, permettre leur élimination sélective et finalement réduire la récurrence de la tumeur. Dans ce travail, le SDF-1α a été initialement encapsulé dans des nanoparticules à base d'acide poly-lactique-co-glycolique (PLGA). Une efficacité d'encapsulation élevée (76%) a pu être obtenue en utilisant un processus simple de séparation de phase. Les nanoparticules chargées de SDF-1α ont ensuite été incorporées dans un scaffold à base de chitosan par électrofilage pour obtenir des implants nanofibreux imitant la structure de la matrice extracellulaire du cerveau. Une étude de libération in vitro a révélé que l'implant pouvait fournir une libération prolongée de SDF-1α jusqu'à 35 jours, utile pour établir un gradient de concentration de SDF-1α dans le cerveau et induire une attraction des cellules GBM. Une étude de biocompatibilité in vivo à 7 jours a révélé des signes d'inflammation locale sans aucun signe visible de détérioration clinique chez les sujets animaux. Une étude à 100 jours visant à confirmer l'innocuité in vivo des implants avant de passer aux études d'efficacité dans un modèle de résection GBM approprié est actuellement en cours. / Glioblastoma (GBM) is the most common and lethal form of brain cancer. The diffusive nature of GBM means the neoplastic tissue can not be removed completely by surgery. Often, residual GBM cells can be found close to the border of the resection cavity and these cells can multiply to cause tumor recurrence in ≥90% of GBM patients. An implant that can sustainably release chemoattractant molecules called stromal cell-derived factor-1α (SDF-1α), which bind selectively to CXCR4 receptors on the surface of GBM cells, may be useful for inducing chemotaxis and recruitment of the residual GBM cells. This may then give access to selective killing of the cells and ultimately reduce tumor recurrence. In this work, SDF-1α was initially encapsulated into poly-lactic-coglycolicacid (PLGA)-based nanoparticles. A high encapsulation efficiency (76%) could be achieved using a simple phase separation process. The SDF-1α-loaded nanoparticles were then incorporated into a chitosan-based scaffold by electrospinning to obtain nanofibrous implants that mimic the brain extracellular matrix structure. In vitro release study revealed that the implant could provide sustainedSDF-1α release for 5 weeks. The gradual SDF-1αrelease will be useful for establishing SDF-1α concentration gradients in the brain, which is critical for the chemotaxis of GBM cells. A 7-day in vivo biocompatibility study revealed evidence of inflammation at the implantation site without any visible signs of clinical deterioration in the animal subjects. A long-term study (100 days) aiming to confirm the in vivo safety of the implants before proceeding to efficacy studies in a suitable GBM resection model is currently underway.

No / Novel 1- and 1,4-substituted chloroethylaminoanthraquinones with DNA binding and alkylating properties along with their respective hydroxyethylaminoanthraquinone intermediates were synthesized. Selected chloroethylaminoanthraquinones were shown to cross-link DNA and alkylate guanines (at low nM concentration) with a preference for reaction sites containing 5'-PyG. A compound (Alchemix) with the bis-chloroethyl functionality confined to one side chain alkylated but did not cross-link DNA. All the 1,4-disubstituted chloroethylaminoanthraquinones were potently cytotoxic (nM IC50s) against cisplatin-resistant ovarian cancer cell lines.

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