Introdução: Aneurisma de aorta é considerado uma doença inflamatória crônica, mas ainda é controverso se está relacionado a aterosclerose aos agentes infecciosos. Antígenos de Chlamydophila pneumoniae (CP) e Mycoplasma pneumoniae (MP) foram encontrados em grande quantidade nas placas instáveis que usualmente estão associadas a remodelamento positivo e inflamação do vaso. Metaloproteinase da matriz 9 (MMP-9) está implicada na fragilidade da parede vascular e na formação dos aneurismas. Os efeitos imunomodulatórios dos receptores ativados por proliferador de peroxissomo (PPARs) têm sido relacionados à aterosclerose. Objetivos: Comparar lesões ateroscleróticas graves com e sem aneurisma do ponto de vista inflamatório e infeccioso, analisando antígenos de MP e CP e expressão de MMP-9, TIMP-1 e PPARs. Métodos: No presente estudo quantificamos, através da técnica de imunoistoquímica, antígenos de MMP- 9, TIMP-1, PPARs a e , e dos agentes infecciosos CP e MP em fragmentos de aorta ateroscleróticos com aneurisma (n=14) e sem aneurisma (n=14). Resultados: A adventícia e o tecido adiposo periadventicial (TAP) dos aneurismas apresentaram intensa inflamação. Expressão de MMP-9 esteve aumentada no TAP e agentes infecciosos, TIMP-1 e PPAR a estiveram aumentados na adventícia e no TAP, sem diferença em relação a expressão de PPAR . Colágeno, TIMP-1 e PPARs estiveram positivamente correlacionados no grupo com aterosclerose, mas não no grupo com aneurisma. Conclusão: Nossos achados sugerem que aneurisma de aorta é uma complicação das lesões ateroscleróticas. Quantidade aumentada de Chlamydophila pneumoniae e Mycoplasma pneumoniae na adventícia e PAT sem correlação da resposta de TIMP-1 e PPARs são achados que estão associados com a presença de aneurisma nos segmentos de aorta ateroscleróticos / Introduction: Aortic aneurysm is considered a chronic inflammatory disease, but remains a controversial matter if it is related to atherosclerosis and infectious agents. Chlamydophila pneumoniae (CP) and Mycoplasma pneumoniae (MP) antigens were found in higher amount in unstable plaques that are usually associated to positive remodeling and vessel inflammation. Matrix metalloproteinase 9 (MMP-9) has been implicated in vascular wall fragility and aneurysm development. The immunemodulator effects of peroxisome proliferators - activated receptor (PPARs) have been related to atherosclerosis. Objectives: To compare severe atherosclerotic lesions with and without aneurysms by inflammatory and infectious point of view, analyzing MP and CP, MMP-9, TIMP-1 and PPARs antigens. Methods: In the present study we quantified, using immunohistochemistry technique, MMP-9, TIMP-1, PPAR a and and infectious agents CP and MP antigens in aortic atherosclerotic fragments with aneurysms. (n=14) and without aneurysms (n=14). Results: Adventitia and periadventitial adipose tissue (PAT) from aneurysms showed intense inflammation. MMP-9 expression has increased in PAT and the infectious agents, TIMP-1 and PPAR a were increased in adventitia and PAT in aneurysmatic group, without difference related to PPAR expression. Collagen, TIMP-1 and PPARs were positively correlated in atherosclerotic group, but it was not observed in aneurysmatic group. Conclusion: Our data have suggested that aortic aneurysm is a complication of aortic atherosclerotic lesions. Increased amount of Chlamydophila pneumoniae and Mycoplasma pneumoniae in the adventitia and PAT without a correlated TIMP-1 and PPARs response are findings that were associated with the presence of aneurysm in atherosclerotic aortic segments

Os modelos experimentais têm sido utilizados para o estudo dos mecanismos fisiopatológicos envolvidos no desenvolvimento da Doença Pulmonar Obstrutiva Crônica (DPOC). O modelo que melhor mimetiza a doença em humanos é o que utiliza a exposição à fumaça de cigarro. No entanto, a utilização deste modelo experimental requer um longo tempo de exposição (6 meses) e a lesão do parênquima obtida é considerada leve. O desequilíbrio protease/anti-protease é considerado um importante mecanismo fisiopatológico envolvido no desenvolvimento da DPOC. Desta forma, neste estudo propomos o desenvolvimento de um modelo experimental no qual associamos a instilação de elastase previamente ao início da exposição ao fumo na tentativa de obter um maior grau de lesão tecidual em um menor espaço de tempo. Para tanto, camundongos C57Bl/6 foram divididos em quatro grupos: Controle, Elastase, Fumo, Fumo/Elastase 1 dose e Fumo/Elastase 2 doses e analisados após dois meses de exposição. Os animais do grupo Fumo/Elastase 1 dose e 2 doses foram submetidos à instilação intranasal de elastase pancreática de porco (0,33UI) e expostos a fumaça de cigarro por dois meses. O grupo controle recebeu o mesmo tratamento com solução fisiológica (NaCl 0.9%). A exposição ao fumo foi feita por 30min, 2 vezes/dia, 5 dias da semana. Após dois meses, os animais foram sacrificados e observamos aumento de LM no grupo Fumo/Elastase 1 dose e 2 doses comparado aos grupos Controle e Fumo; aumento de células positivas para MAC-2 no parênquima (Fumo/Elastase 2 doses) e vias aéreas (Fumo/Elastase 1 dose e 2 doses), MMP-12 no parênquima pulmonar (Fumo/Elastase 2 doses), GP91 no parênquima (Fumo/Elastase 1 dose e 2 doses) e vias aéreas (Fumo e Fumo/Elastase 1 dose) e aumento de proporção de fibras elásticas no parênquima pulmonar do grupo Fumo/Elastase 1 dose e do grupo Fumo, caracterizando presença de enfisema pulmonar. A instilação de elastase pancreática de porco juntamente com a exposição à fumaça de cigarro aumentou a susceptibilidade ao desenvolvimento do enfisema / Experimental models have been used to study the pathophysiological mechanisms involved in the development of COPD. Cigarette Smoke exposure (CS) is considered the best model to mimetize the disease in humans. However, the CS requires a long exposure time (6 months) and the parenchymal destruction obtained is considered mild. The protease / anti - protease imbalance is considered an important pathophysiological mechanism involved in the development of COPD. Thus, in this study we propose the development of an experimental model in which we associate instillation of elastase before the start of exposure to smoke, trying to increase the parenchymal destruction degree in a shorter time. For that, C57BL / 6 mice were divided into four groups: Control, Elastase, Smoke and Smoke/Elastase 1 dose and Smoke/Elastase 2 doses and analyzed in two months after the CS exposition. The Smoke/Elastase 1 dose and 2 doses animals group received an intranasal instillation of porcine pancreatic elastase (0.33 IU) and exposed to cigarette smoke for two months. The control group received the same treatment with saline (NaCl 0.9 %). Animals were exposed to CS for 30min, 2 times / day, 5 days a week. After two months, we observed increased mean linear intercept (LM) and positive cells for MAC-2, MMP-12 and GP91 in the airways and lung parenchyma and increase of elastic fibers in the lung parenchyma characterizing the presence of pulmonary emphysema. The instillation of porcine pancreatic elastase along the exposure to cigarette smoke increased susceptibility to the development of emphysema

INTRODUÇÃO: O câncer de vulva representa entre 3 a 5% dos cânceres do trato genital feminino e aproximadamente 0,6% dos cânceres da mulher. Existem poucos estudos na literatura sobre fatores prognósticos incluindo avaliação molecular, relacionados a esta doença. Este estudo foi realizado para avaliar fatores prognósticos clínicos, epidemiológicos, patológicos e moleculares de pacientes portadores de câncer de vulva submetidos a tratamento cirúrgico. Avaliamos também uma classificação de prognóstico com base na pontuação do risco relativo dos fatores encontrados. MÉTODOS: Foram selecionadas as pacientes portadoras de carcinoma escamocelular de vulva, submetidas a tratamento cirúrgico no Departamento de Cirurgia Pélvica e Serviço de Ginecologia do Hospital Aristides Maltez entre o período de Junho de 1993 e Junho de 2011. Avaliamos as características clínicas, epidemiológicas, de anatomia patológica e molecular, em relação ao prognóstico das pacientes. A avaliação molecular estudou a expressão da proteína p53 e metaloproteinase 2 de matriz por exame de imunohistoquímica pela técnica de arranjo em matriz de amostras teciduais (TMA). Com base no banco de dados realizado através de consulta aos prontuários e com os resultados de anatomia patológica e testes imunohistoquímicos realizamos análise estatística em relação à sobrevida global das pacientes.RESULTADOS: Setenta e cinco pacientes foram elegíveis para o estudo. A análise univariada mostra como fatores relacionados à sobrevida foram a presença de linfonodo suspeito de metástase ao exame clínico (p=0,004), o tamanho maior de 4 centímetros (p=0,001), a presença de linfonodo com metástase (p=0,026), o estadiamento por grupos (p=0,001), a localização mediana (p=0,011), a profundidade de infiltração maior de 2 milímetros (p=0,012), a expressão da MMP 2 em mais de 50% das células (p=0,009). Na análise multivariada os fatores relacionados à sobrevida foram o tamanho maior de 4 centímetros (p=0,014), a profundidade de invasão maior de 2 milímetros (p=0,023) e a expressão de MMP2 em mais de 50% das células (p=0,046). De acordo ao risco relativo dos fatores identificados como relacionados ao prognóstico pela análise multivariada, foi elaborada a contagem de pontos para uma classificação prognóstica. Essa pontuação classifica em três categorias conforme a presença ou ausência dos fatores identificados na análise multivariada e pode corresponder a três expectativas de sobrevida. CONCLUSÕES: Os fatores tamanho maior de 4 centímetros, profundidade de invasão maior de 2 milímetros e expressão em mais de 50% das células tumorais de metaloproteinase 2 parecem estar relacionados a menor taxa de sobrevida global de pacientes portadores de câncer de vulva submetidas a tratamento cirúrgico. Pode ser realizada uma classificação para o prognóstico de acordo com uma contagem de pontos atribuídos ao risco relativo destes fatores / INTRODUCTION: Vulvar cancer accounts for 3-5% of all cancers of the female genital tract and approximately 0.6% of women\'s cancers. There are few studies on prognostic factors including molecular evaluation related to this disease. This study was conducted to evaluate clinical, epidemiological, pathological and molecular prognostic factors of patients with vulvar cancer, undergoing surgical treatment. A classification based on prognostic risk score related to the factors found was also evaluated. METHODS: Patients were selected with squamous cell carcinoma of the vulva who underwent surgical treatment at the Department of Pelvic Surgery and Department of Gynecology, Hospital Aristides Maltez between the period of June 1993 and June 2011. Clinical, epidemiological, and molecular and pathological anatomy characteristics were evaluated in relation to the prognosis of patients. Molecular assessment studied the expression of p53 protein and metalloproteinase 2 by immunohistochemical examination through the technical arrangement on matrix tissue samples (TMA). Based on the database performed on medical records held and the results of pathological anatomy and immunohistochemical tests, the statistical analysis was performed with respect to overall survival of patients. RESULTS: Seventy-five patients were eligible for the study. Univariate analysis shows how factors related to survival were the presence of lymph node metastasis suspected on clinical examination (p = 0.004), the larger size of 4 cm (p = 0.001), presence of lymph node metastasis (p = 0.026), staging groups (p = 0.001), the location median (p = 0.011), the depth of infiltration larger than 2 millimeters (p = 0.012), the expression of MMP 2 in more than 50% of the cells (p = 0.009). In multivariate analysis, factors related to survival were larger size than 4 cm (p = 0.014), depth of invasion greater than 2 mm (p = 0.023) and MMP2 expression in more than 50% of cells (p = 0.046). According to the relative risk of factors identified as related to prognosis by multivariate analysis, a score was developed for a prognostic classification. This score classifies into three categories, according to the presence or absence of the factors identified in the multivariate analysis and may correspond to three survival expectations. CONCLUSIONS: Prognostic factors as the size larger than 4 centimeters, depth of invasion greater than 2 mm and expression in more than 50% of tumor cells of metalloproteinase 2 may be related to lower overall survival rate of patients with cancer of the vulva undergoing surgery. Classification may be performed for the prognostic according to a count point attributed to the relative risk of these factors

Abstract Tumor associated macrophages (TAMs) are linked to the invasion of oral tongue squamous cell carcinoma (OTSCC). We modified THP-1 leukemia cells to M1 (inflammatory), M2 (TAM-like) and R848 (imidazoquinoline-treated) type macrophages in order to examine their interactions with OTSCC-cells (HSC-3) by using different kinds of in vitro migration and invasion models. We observed that interaction of TAM-resembling M2-type macrophages with HSC-3 cells induced invasion and migration, whereas the influence of M1 macrophages reduced them. Patient response to chemoradiotherapy is highly reliant on the characteristics such as the aggressiveness and stage of the cancer. Therefore, new methods for treatment testing are needed in order to design personalized therapies. We tested the applicability and consistency of human TME mimicking tissue methods for analyzing the effects of chemoradiation using commercial OTSCC cell lines. Based on our trials, both our human uterine leiomyoma tissue -based matrix models provide viable platforms for future in vitro chemoradiotherapy testing. Conventionally pro-tumorigenic activities of matrix metalloproteinase (MMP)9 have been linked with oral squamous cell carcinoma, but recently its tumor-suppressor role has also been revealed. Our study provides strong evidence that MMP9 also has an anti-invasive effect in OTSCC and is a potential mediator of the protective effects of arresten in tongue cancer cells. / Tiivistelmä Makrofageilla on yhteys kielen levyepiteelikarsinooman invaasioon eli syöpäkasvaimen tunkeutumiseen ympäröivään kudokseen. Tutkimuksessamme muokkasimme ihmisen THP-1 leukemiasoluja kemiallisesti tulehdusreittejä aktivoiviksi M1-makrofageiksi, kasvaimeen liittyvien makrofagien kaltaisiksi M2-makrofageiksi sekä imidatsokinoliini-käsitellyiksi R848-makrofageiksi. Tarkoituksenamme oli tutkia makrofagien ja kielisyöpäsolujen vuorovaikutuksia erilaisilla in vitro migraatio- ja invaasiomalleilla. Anti-inflammatoristen, syövän etenemistä edesauttavien TAM-makrofagien kaltaisiksi erilaistetut M2-tyypin makrofagit lisäsivät HSC-3 kielikarsinoomasolujen invaasiota ja migraatiota, kun taas M1-tyypin makrofagien vaikutus oli päinvastainen. Potilaan vaste kemosädehoitoon riippuu syöpäkasvaimen ominaisuuksista, kuten syöpäsolujen aggressiivisuudesta ja syövän levinneisyysasteesta. Tämän vuoksi on tarve uusille menetelmille, joiden avulla voidaan ottaa huomioon potilaan sekä syöpätyypin yksilölliset ominaisuudet hoitoa suunniteltaessa. Testasimme syöpäkasvaimen mikroympäristöä mallintavien, ihmiskudokseen perustuvien menetelmien käyttökelpoisuutta ja luotettavuutta kemosädehoidon vaikutusten arvioimiseen. Testiemme perusteella myoomakudokseen pohjautuvat menetelmät voivat auttaa kemosädehoidon vaikutusten testauksessa. Matriksin metalloproteinaasi (MMP) 9:n on pitkään uskottu olevan yksinomaan syövän etenemistä edesauttava molekyyli. Viimeaikaisissa tutkimuksissa on myös havaittu, että MMP9:llä voi olla syövältä suojaavia vaikutuksia. Tutkimme MMP9:n vaikutusta kielisyöpäsoluihin ja havaitsimme, että MMP9:llä on myös invaasiota hillitseviä vaikutuksia. Lisäksi MMP9 saattaa toimia verisuonten muodostumista estävän arresten-molekyylin syövältä suojaavien mekanismien välittäjänä.

Scar-free wound healing and regeneration are uncommon phenomena permitting the near complete restoration of damaged tissues, organs and structures. Although rare in mammals, many lizards are able to undergo scarless healing and regeneration following loss of the tail. This study investigated the spontaneous and intrinsic capacity of the leopard gecko (Eublepharis macularius) tail to undergo scar-free wound healing and regeneration following two different forms of tail loss: autotomy, a voluntary and evolved mechanism of tail shedding at fracture planes; and surgical amputation, involuntary loss of the tail outside the fracture planes. Furthermore, I investigated the ability of the regenerate tail to regenerate by amputating a regenerate tail (previously lost by autotomy). To investigate these phenomena I imaged wound healing and regenereating tails daily (following autotomy and amputation) to document gross morphological changes. I used histochemistry to document tissue structure and immunohistochemistry to determine the tissue/cellular location of my five proteins of interest (PCNA, MMP-9, WE6, α-sma, TGF-β3). Each of these proteins of interest has been previously documented during wound healing and/or regeneration in other wound healing/regeneration model organisms (e.g. mice, urodeles, lizards, zebrafish). Scar-free wound healing and regeneration occurred following autotomy, amputation of the original tail and amputation of the regenerate tail, indicating that the leopard gecko tail has an instrinsic scar-free wound healing and regenerative capacity that is independent of the mode of tail loss (autotomy or amputation). Furthermore immunohistochemistry revealed a conserved sequence and location of the expression of the five proteins of interest following both forms of tail loss. These results provide the basis for further studies investigating scar-free wound healing and regeneration in a novel amniote model, the leopard gecko. / NSERC

Le PCK3145 est un peptide de 15 acides aminés inhibant la sécrétion de MMP-9 et démontrant une activité anti-tumorale contre le cancer de la prostate. Comme les cancers hématologiques sécrètent MMP-9, nous avons donc évalué l’effet du PCK3145 sur ces cancers. Nous avons démontré que les lignées humaines de lymphome non- Hodgkinien (LNH) SR et de myélome multiple RPMI-8226 ainsi que la lignée murine de mastocytome P815 ont une prolifération réduite suite à une exposition au PCK3145. Ce peptide diminue également la clonogénicité de ces cellules. In vivo, le PCK3145 diminue significativement la croissance des tumeurs sous-cutanées P815 comparativement au PBS (p<0.001) et aux peptides contrôles (« scrambled peptide » (p<0.05) et PCK5266 (p<0.01)). De plus, le traitement au PCK3145 diminue le nombre de métastases au niveau du foie par rapports aux contrôles (p<0.05). Les niveaux de MMP-9 dans le sang des souris traitées au PCK3145 sont similaires à ceux dans le sang des souris sans tumeur. Par contre, chez les souris recevant le PBS ou le « scrambled peptide », les niveaux de MMP-9 étaient significativement plus élevés que dans les souris sans tumeur et les souris traitées au PCK3145 (p<0.05). De surcroît, dans un modèle de xénogreffe, le PCK3145 diminue significativement la croissance des lymphomes SR par rapport au PBS (p<0.01) et au « scrambled peptide » (p<0.001). Ces résultats indiquent que le PCK3145 possède une activité anti-tumorale et pourrait représenter un agent intéressant pour le traitement de plusieurs cancers hématologiques. / PCK3145 has been shown to exert anti-tumor activity against prostate cancer cells. In a Phase I clinical study, this peptide demonstrated low toxicity. To determine whether PCK3145 could exert cytotoxic activity against other marrow infiltrating cancers, we tested its activity against hematologic cancers. Interestingly, PCK3145 inhibited the proliferation of human NHL (SR) and myeloma (RPMI-8226) cell lines and murine mastocytoma (P815) cell line in vitro. Moreover, PCK3145 reduced the clonogenicity of these cell lines. To explore its activity in vivo, DBA/2 mice were injected with P815 cells. PCK3145 treatment significantly decreased P815 tumors growth in comparison to PBS (p<0.001), scrambled peptide (p<0.05) and PCK5266 (amino acids 52-66 of PSP-94) (p<0.01). Intraperitoneal PCK3145 treatment led to a decreased number of liver metastasis compared to PBS (p<0.05) and scrambled peptide (p<0.05). MMP-9 levels, measured by ELISA, in the peripheral blood of treated P815 bearing mice were similar to those obtained with healthy animals (12.83 1.890 (mean SD) ng/ml and 6.48 0.4070 ng/ml, respectively), while MMP-9 levels were elevated in mice treated with PBS and scrambled peptide (35.12 8.559 ng/ml and 22.60 3.944 ng/ml, respectively; p<0.05). In NOD/SCID mice PCK3145 treatment resulted in significant inhibition of human NHL SR growth compared to treatment with PBS (p<0.001) and scrambled peptide (p<0.01). Consequently, treatment with PCK3145 can reduce tumor cell proliferation of murine and human hematologic cancers. In addition, PCK3145 has the potential to inhibit tumor cells dissemination by lowering MMP-9 secretion. Thus, PCK3145 represents a unique peptide demonstrating sequence-specific anti-tumor activity hematologic malignancies.

Le RXP470.1 est l’un des premiers inhibiteurs puissants de la MMP-12, une métalloprotéase à zinc impliquée dans de nombreuses pathologies comme l’athéroclérose et la bronchopneumopathie obstructive chronique (BPCO). Pour comprendre les bases moléculaires contrôlant l’interaction de cet inhibiteur avec sa cible, des approches pluridisciplinaires associant des relations structure-activité, avec des études de cristallographie de complexes enzymes inhibiteurs et d’études de microcalorimétrie, décrivant les contributions enthalpiques et entropiques impliquées dans la formation des complexes, ont été réalisées dans ce travail de thèse. Les affinités de trois analogues du RXP470.1 ont été tout d’abord déterminées. Puis quatre structures cristallographiques de complexes enzyme/inhibiteur décrivant le mode d’interaction duRXP470.1 et de ces trois analogues ont été obtenues avec des résolutions de 1.15 Å, 1.50 Å, 1.50Å et 1.30 Å, respectivement. Parallèlement les études de microcalorimétrie ont été menées pour étudier les facteurs énergétiques contrôlant l’interaction du RXP470.1 avec la MMP-12. Les résultats indiquent que la présence d’une chaîne latérale très longue et hydrophobe en position P1’de l’inhibiteur s’insérant dans la cavité S1’ de la MMP-12 est essentielle à la très bonne affinité de cet inhibiteur pour la MMP-12. Cette interaction met essentiellement en jeu un effet entropique très important de - 4 kcal/mol. L’interaction du RXP470.1 est aussi essentiellement dirigée par une forte augmentation d’entropie (-TDS= -10 kal/mol) et une composante enthalpique beaucoup plus faible (DH= -2.5 kcal/mol), et ce malgré l’observation dans le cristal de nombreuses interactions entre l’inhibiteur et le site actif de la MMP-12. L’étude de microcalorimétrie met aussi en lumière la prise d’un proton au cours de la formation du complexe enzyme inhibiteur impliquant deux résidus chargés négativement en solution, le résidu catalytique Glu219 et le groupe phosphoryle chélatant du zinc dans l’inhibiteur. Cette étude révèle aussi que si le groupe phosphoryle est considéré comme un chélatant faible de l’atome de zinc, il impose néanmoins des contraintes directionnelles très importantes qui ont un impact sur le positionnement des autres parties de l’inhibiteur dans le site actif de l’enzyme. Ce dernier effet pourrait expliquer pourquoi un certain nombre d’interactions entre l’inhibiteur et l’enzyme ne sont pas optimisées et pourquoi la variation d’enthalpie pour former le complexe reste relativement faible. Cette étude ouvre maintenant la voie à d’autres études en plaçant au centre des futurs travaux le rôle du groupe chélatant dans la conception des inhibiteurs de MMP, ainsi de nouveaux inhibiteurs puissants et sélectifs d’autres MMP devraient voir le jour grâce à ce travail et aux résultats obtenus. / RXP470.1 is one of the first highly potent and selective inhibitor of MMP-12, a zinc protease involved in several human diseases such as atherosclerosis and chronic obstructive pulmonary disease (COPD). To understand the molecular determinants controlling the interaction of RXP470.1 with MMP-12 active site, a multidisciplinary approach combining structure-activity data, crystallography and microcalorimetry have been performed on RXP470.1 and its three analogues. The affinities of the three RXP470.1 analogues have been determined. Then, fourcrystal structures of MMP-12 in interaction with these inhibitors have beendetermined at high resolution, 1.15 Å, 1.50 Å, 1.50 Å et 1.30 Å, respectively. These data have indicated that the presence of a long hydrophobic side chain in the P1’ position of the RXP470.1, which enters deeply inside the S1’ cavity of MMP-12, is playing a key role in the inhibitor affinity. The contribution of this side chain is mostly entropic (-TDS - 4 kcal/mol). The interaction of RXP470.1 with MMP-12 is also mostly driven by a sizeable entropy increase (-TDS= -10 kal/mol) and a more modest enthalpy contribution (DH= -2.5 kcal/mol), despite the observation in the crystal structure of several contacts between inhibitor and MMP-12 active site. Furthermore, this study reveals that the binding of RXP470.1 to MMP-12 is linked to a proton uptake involving two negatively charged residues, the catalytic Glu219 and the phosphoryl group of the inhibitor. Furthermore, despite that the phosphoryl group is considered as a weak zincbinding group, this study highlights that the interactions of this group with the active site zinc atom involved strong directionality between these two groups. This effect has strong impact on the positioning of the other parts of the inhibitor in the MMP-12 active site. This last effect could be responsible for the modest enthalpy increase associated with the binding of RXP470.1 to MMP-12, by preventing the optimization of several interactions between the inhibitor and the enzyme. The results indicate that the role of the zinc-binding group should be better consider in the future. Finally this study opens a new vision in this field and should allow the design of new selective inhibitors of other MMPs.

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O câncer de mama é uma neoplasia altamente maligna e continua a ser a segunda principal causa de mortalidade entre as mulheres. Os efeitos antitumorais de metaloproteinases e desintegrinas de veneno de serpentes têm sido investigados em vários tipos de células tumorais. Neste estudo, foram avaliados os efeitos antitumorais e anti-angiogênicos induzidos pela Bothropoidina, uma metaloproteinase desintegrina-like isolada da peçonha de Bothrops pauloensis em células de câncer de mama humano MDA-MB-231 e células endoteliais. Após 24 horas de tratamento com 100pg/mL de Bothropoidina foi constatado um efeito citotóxico moderado de 30% em MDA-MB-231 contra 10% de citotoxicidade em MCF10A (uma linha de células da mama não tumorigênica), uma diferença significativa que sugere uma possível preferência desta proteína por alvos em células tumorais. Observou-se apoptose e apoptose tardia após tratamento com Bothropoidina (10pg/mL e 40pg/mL) em células MDA-MB-231. Além disso, esta toxina não só inibiu a adesão de células MDA-MB-231 de uma forma dose dependente, como a migração celular em aproximadamente 45%. Bothropoidina reduziu a viabilidade e adesão de células endoteliais em Matrigel e inibiu a angiogênese in vitro estimulada por bFGF em Matrigel, mostrando um número de vasos formados significativamente menor em relação ao controle. Os resultados demonstraram que Bothropoidina tem um potente efeito antitumoral e antiangiogênico in vitro, representando uma ferramenta biotecnológica para elucidar o efeito antitumoral de metaloproteinases desintegrinas-like em células cancerígenas. / Breast cancer is a highly malignant carcinoma and remains the second leading cause of mortality among women. The antitumor effects of metalloproteinases and disintegrins from snake venom on various types of cancer cells have been investigated. In this study, we evaluated the antitumor and antiangiogenic effects on MDA-MB-231 human breast cancer cells and endothelial cells induced by Bothropoidin, a disintegrin-like metalloproteinase isolated from Bothrops pauloensis snake venom. At 24h after treatment at 100pg/mL, Bothropoidin exerted a moderate cytotoxic effect of 30% on MDA-MB-231 versus 10% cytotoxicity against MCF10A (a non-tumorigenic breast cell line), a significant difference that suggests a possible preference by this protein for targets in cancer cells. Early and late apoptosis of MDA-MB-231 was observed after Bothropoidin treatment (10gg/mL and 40gg/mL). Furthermore, this toxin inhibited not only the adhesion of MDA-MB-231 cells in a dose-dependent manner but also cell migration by approximately 45%. In addition, Bothropoidin decreased endothelial cells viability and adhesion in Matrigel and inhibited in vitro angiogenesis in Matrigel stimulated by bFGF, showing significantly fewer formed vessels. The results demonstrated that Bothropoidin has potent in vitro antitumor and antiangiogenic effect and represents a biotechnological tool for elucidating the antitumor effect of disintegrins-like metalloproteinases in cancer cells. / Dissertação (Mestrado)

Introdução: Aneurisma de aorta é considerado uma doença inflamatória crônica, mas ainda é controverso se está relacionado a aterosclerose aos agentes infecciosos. Antígenos de Chlamydophila pneumoniae (CP) e Mycoplasma pneumoniae (MP) foram encontrados em grande quantidade nas placas instáveis que usualmente estão associadas a remodelamento positivo e inflamação do vaso. Metaloproteinase da matriz 9 (MMP-9) está implicada na fragilidade da parede vascular e na formação dos aneurismas. Os efeitos imunomodulatórios dos receptores ativados por proliferador de peroxissomo (PPARs) têm sido relacionados à aterosclerose. Objetivos: Comparar lesões ateroscleróticas graves com e sem aneurisma do ponto de vista inflamatório e infeccioso, analisando antígenos de MP e CP e expressão de MMP-9, TIMP-1 e PPARs. Métodos: No presente estudo quantificamos, através da técnica de imunoistoquímica, antígenos de MMP- 9, TIMP-1, PPARs a e , e dos agentes infecciosos CP e MP em fragmentos de aorta ateroscleróticos com aneurisma (n=14) e sem aneurisma (n=14). Resultados: A adventícia e o tecido adiposo periadventicial (TAP) dos aneurismas apresentaram intensa inflamação. Expressão de MMP-9 esteve aumentada no TAP e agentes infecciosos, TIMP-1 e PPAR a estiveram aumentados na adventícia e no TAP, sem diferença em relação a expressão de PPAR . Colágeno, TIMP-1 e PPARs estiveram positivamente correlacionados no grupo com aterosclerose, mas não no grupo com aneurisma. Conclusão: Nossos achados sugerem que aneurisma de aorta é uma complicação das lesões ateroscleróticas. Quantidade aumentada de Chlamydophila pneumoniae e Mycoplasma pneumoniae na adventícia e PAT sem correlação da resposta de TIMP-1 e PPARs são achados que estão associados com a presença de aneurisma nos segmentos de aorta ateroscleróticos / Introduction: Aortic aneurysm is considered a chronic inflammatory disease, but remains a controversial matter if it is related to atherosclerosis and infectious agents. Chlamydophila pneumoniae (CP) and Mycoplasma pneumoniae (MP) antigens were found in higher amount in unstable plaques that are usually associated to positive remodeling and vessel inflammation. Matrix metalloproteinase 9 (MMP-9) has been implicated in vascular wall fragility and aneurysm development. The immunemodulator effects of peroxisome proliferators - activated receptor (PPARs) have been related to atherosclerosis. Objectives: To compare severe atherosclerotic lesions with and without aneurysms by inflammatory and infectious point of view, analyzing MP and CP, MMP-9, TIMP-1 and PPARs antigens. Methods: In the present study we quantified, using immunohistochemistry technique, MMP-9, TIMP-1, PPAR a and and infectious agents CP and MP antigens in aortic atherosclerotic fragments with aneurysms. (n=14) and without aneurysms (n=14). Results: Adventitia and periadventitial adipose tissue (PAT) from aneurysms showed intense inflammation. MMP-9 expression has increased in PAT and the infectious agents, TIMP-1 and PPAR a were increased in adventitia and PAT in aneurysmatic group, without difference related to PPAR expression. Collagen, TIMP-1 and PPARs were positively correlated in atherosclerotic group, but it was not observed in aneurysmatic group. Conclusion: Our data have suggested that aortic aneurysm is a complication of aortic atherosclerotic lesions. Increased amount of Chlamydophila pneumoniae and Mycoplasma pneumoniae in the adventitia and PAT without a correlated TIMP-1 and PPARs response are findings that were associated with the presence of aneurysm in atherosclerotic aortic segments