O cÃncer do colo do Ãtero à um dos mais preocupantes problemas de saÃde pÃblica do planeta. SÃo esperados para 2013, no Brasil, 17.540 casos novos. Acredita-se atualmente que a maior parte dos cÃnceres cervicais se desenvolve a partir das neoplasias intraepiteliais cervicais. A aquisiÃÃo de propriedades invasivas dos tumores malignos està associada ao desequilÃbrio nas adesÃes intercelulares. As molÃculas de adesÃo tÃm papel fundamental nestas uniÃes e a caderina-E à uma das mais importantes. Està comprovada a sua presenÃa na membrana celular de tecidos epiteliais normais e foi demonstrado que esta proteÃna tem sua expressÃo diminuÃda na maioria dos tumores sÃlidos, o que favorece o processo de invasÃo. O objetivo, neste estudo, foi investigar a imunoexpressÃo da caderina-E nas Cervicites, nas LesÃes Intraepiteliais Escamosas (LIE) e no Carcinoma Invasivo do colo uterino. A amostra consistiu de 83 casos de biÃpsias e cones de colo do Ãtero obtidos dos arquivos do Departamento de Patologia e Medicina Legal da Universidade Federal do CearÃ, em 2007 e 2010, com os seguintes diagnÃsticos: Cervicite = 8 casos; LesÃo Intraepitelial Escamosa de Baixo Grau (LIEBG) = 24 casos; LesÃo Intraepitelial Escamosa de Alto Grau (LIEAG) = 28 casos; Carcinoma Invasor = 23 casos. A imunohistoquÃmica (IHQ) foi efetuada com o anticorpo monoclonal anti-caderina-E, tendo sido considerada positiva a presenÃa de expressÃo membranar, e negativa, a ausÃncia de expressÃo. O teste exato de Fisher foi utilizado para os cÃlculos das tabelas de contingencias. Os resultados da imunomarcaÃÃo foram: Cervicites = 1/8 (12%) negativos e 7/8 (88%) casos positivos para caderina-E; LIEBG = 7/24 (29%) casos negativos e 17/24 (71%) positivos; LIEAG = 7/28 (25%) negativos e 21/28 (75%) positivos; Carcinoma Invasor = 19/23 (83%) negativos e 4/23 (17%) positivos. A expressÃo negativa foi muito mais frequente nas LIEs (27%), comparadas com as Cervicites (12%) apesar de diferenÃa nÃo significante (p = 0,6657). Nas LIEs, uma maior perda da caderina-E foi notada nas cÃlulas menos diferenciadas do 1/3 basal da espessura epitelial. Finalmente, observou-se que a ausÃncia de expressÃo membranar da caderina-E foi muito mais frequente no carcinoma epidermÃide invasor do que nas lesÃes intraepiteliais escamosas do colo do Ãtero. Estes dados mostraram a importÃncia da caderina-E na carcinogÃnese do colo uterino, no entanto, muitos aspectos permanecem sem explicaÃÃo e novos estudos sÃo necessÃrios. / Cervical cancer is one of the most important public health problems around the world. About 17.540 new cases are expected, in Brazil, for 2013. Actually, itâs believed that the majority of cervical cancers begin with non invasive dysplastic lesions, the cervical intraepithelial neoplasias. The acquisition of invasive properties, in epithelial malignancies, is associated to the disruption of intercellular adhesions. The adhesion molecules play a pivotal role in these intercellular bindings and E-cadherin is considered one of the most important among them. In normal epithelial tissues its presence in cell membrane is recognized and it was shown that a down regulation of these proteins in the majority of solid tumors may contribute to facilitate the invasive process. The aim, of this research, was to investigate the E-cadherin immunoexpression in cervicitis, in SILs and in the invasive carcinomas of the uterine cervix. Samples specimens consisted of 83 cases of uterine cervical biopsies and conizations retrieved from the Department of Pathology and Forensic Medicine files of the Federal University of Cearà (Brazil) in 2007 and 2010, distributed, by diagnostic, as follows: Cervicitis = 8 cases; Low Squamous Intraepithelial Lesion (LSIL) = 24 cases; High Squamous Intraepithelial Lesion (HSIL) = 28 cases; and Invasive Carcinoma = 23 cases. Immunohistochemistry (IHC) was performed with the anti-E-cadherin monoclonal antibody and it was considered positive the membranar expression, and, negative, the absence of membranar expression. The Fisherâs exact test was the choice for the contingency tables calculations. The immunostaining results were: Cervicitis = (12%) negative and 7/8 (88%) positive cases to E-cadherin; LSILs = 7/24 (29%) negative cases and 17/24 (71%) positive; HSILs = 7/28 (25%) negative and 21/28 (75%) positive; Invasive Carcinoma = 19/23 (83%) negative and 4/23 (17%) positive. The negative expression was much more frequent in SILs (27%) when compared to cervicitis (12%), although no significant difference (p = 0,6657). In SILs, a bigger E-cadherin loss was noted in undifferentiated cells at the basal third of epithelial thickness. Finally it was shown that the absence of E-cadherin membranar expression was much more frequent in the uterine cervix invasive carcinoma when compared to LSILs and HSILs. These data showed the E-cadherin importance in cervical carcinogenesis, nonetheless, several aspects remain without explication and new researches are to be performed.

Os tumores cutâneos e subcutâneos em cães representam um terço das neoplasias nessa espécie. O carcinoma de células escamosas (CCE) é uma neoplasia maligna com origem no epitélio estratificado escamoso da pele e de outras superfícies mucosas. A etiologia do CCE em cães não é bem definida, porém é descrito que a exposição aos raios solares é um importante fator para seu desenvolvimento. O CCE, frequentemente, é precedido pela ceratose actínica (CA). Este trabalho tem como objetivo comparar aspectos clínicos, morfológicos e moleculares da ceratose actínica e carcinoma de células escamosas da pele da região abdominal ventral de cães. Foram coletadas dez amostras de pele apresentando CCE e 9 amostras de pele apresentando CA da região abdominal ventral de caninos domésticos. As amostras foram fixadas em formol a 10%, e rotineiramente processadas para inclusão em parafina. Os cortes histológicos de 5?m foram submetidos à coloração de Hematoxilina e Eosina, para análise histopatológica, e às marcações, por imuno-histoquímica, de E-caderina, p53, Ciclo-oxigenase-2, pancitoqueratina AE1/AE2, vimentina, 5 metilcitosina e Ki67. As expressão de E-caderina, p53, ciclo-oxigenase-2, pancitoqueratina AE1/AE e vimentina foram avaliadas qualititivamente nas 9 amostras de CA e 10 amostras CCE, respectivamente. A metilação global do DNA e a proliferação celular (Ki67) foram quantificadas nos cortes histológicos de CA e CCE por meio da contagem de núcleos de células epiteliais marcados positiva ou negativamente. Os dados foram analisados por meio de testes uni e multivariados. Os cães machos da raça American PitBull Terrier de pelagem branca foram os mais acometidos pela CA e CCE, com média de idade de 8,1 e 8,4 anos, respectivamente. Não houve associação significativa na expressão de p53, COX-2 e vimentina na CA e CCE. Houve aumento no número de células com o núcleo marcado positivamente para Ki-67 e 5 metilcitosina em CCE comparado a CA. Observou-se, também, marcação heterogênea de Ecaderina em CCE. Constatou-se também diminuição na expressão de pancitoqueratina AE1/AE3 quando há invasão linfática e maior expressão de 5 metilcitosina em cães mais idosos, no CCE. Estes achados sugerem que há diferenças entre CA e CCE em relação aos parâmetros estudados, que condizem com a transformação maligna da afecção / Cutaneous and subcutaneous tumors in dogs account for a third of neoplasms in this species. Squamous cell carcinoma (SCC) is a malignant neoplasm that originates in the stratified squamous epithelium of the skin and other mucosal surfaces. The etiology of SCC is not well defined, however it is described that exposure to the sunlight is an important factor for its development. SCC is often preceded by actinic keratosis (AK). This work aims to compare clinical, morphological and molecular aspects of actinic keratosis and squamous cell carcinoma of the skin of the ventral abdominal region of dogs. Ten samples of SCC and 9 skin samples showing AK of the ventral abdominal region of domestic canines were collected. As samples were fixed in 10% formaldehyde, and routinely processed for inclusion in paraffin. Histological sections of 5?m were submitted to staining of Hematoxylin and Eosin for histopathological analysis, and to immunohistochemistry of E-cadherin, p53, Cyclooxygenase-2, pancytokeratin AE1/AE2, vimentin, 5 methylcytosine and Ki-67. The expression of E-cadherin, p53, cyclooxygenase-2, pancytokeratin AE1 / AE and vimentin were qualitatively evaluated in the 9 AK samples and 10 SCC samples, respectively. Overall DNA methylation and cell proliferation (Ki67) were quantified in the histological sections of AK and SCC by counting nuclei of positively or negatively labeled epithelial cells. The data were analyzed by means of uni and multivariate tests. Male dogs of the American PitBull Terrier breed were the most affected by AK and SCC, with an average age of 8.1 and 8.4 years, respectively. There was no significant association in the expression of p53, COX-2 and vimentin in CA and CCE. There was an increase in the number of cells with the nucleus positively labeled for Ki-67 and 5 methylcytosine in CCE compared to CA. There was also a heterogeneous labeling of Ecaderin in CCE. It was also observed a decrease in the expression of pancytokeratin AE1/AE3 when there is lymphatic invasion and greater expression of 5 methylcytosine in older dogs in the ECC. These findings suggest that there are differences between CA and SCC in relation to the studied parameters, which are consistent with the malignant transformation of the disease

Em virtude dos pobres resultados obtidos no tratamento do Câncer de Pulmão, seja em estágios iniciais ou na doença avançada localmente, há a necessidade de se desenvolver marcadores moleculares e imunohistoquímicos que possam prever o comportamento tumoral. Ácido Hialurônico (HA) é um componente da matriz extracelular, responsável pela hidratação e manutenção do equilíbrio osmótico tecidual. Concentrações de HA estão elevadas em vários tipos de cânceres, incluindo pulmão. Hialuronidases (HAases), são uma família de enzimas relacionadas com a propagação de infecções bacterianas, toxinas de venenos e progressão tumoral. A quebra do HA em pequenos fragmentos (3-25 dissacarídeos) promovidos pela ação das HAases tipo Hyal1, Hyal2 e Hyal3, está relacionada à promoção do câncer através da indução da angiogênese e estímulo a proliferação através de ativação da via tirosina quinase. Algumas isoformas de HAases, descritas como produto de splicing alternativo, possuem atividade enzimática diversificada. A heterogeneidade de expressão das HAases foi identificada em alguns tipos de câncer e pode ser correlacionada com o comportamento diferenciado dos tumores. Em uma primeira instância, o perfil de expressão das HYAL foi avaliado em tecidos pulmonares tumorais e normais de 69 tumores ressecados de pacientes com adenocarcinomas (ADC) e carcinomas de células escamosas (CCE) oriundos do Hospital das Clinicas e Hospital do Câncer AC. Camargo. A expressão da HYAL1- selvagem (wt) e variantes 1 a 5, HYAL2-wt, HYAL3-wt e variantes 1 a 3 foi identificada por PCR e seqüenciamento direto. Diferentes proporções de HYAL3-wt e variantes foram expressas em tecidos pulmonares tumorais e controles. HYAL1-wt esteve associada com prognóstico desfavorável e HYAL3-v1 com prognóstico favorável. Diante dos resultados obtidos dos tumores de pacientes do Hospital das Clínicas e Hospital AC. Camargo, prosseguimos a investigação para estudar a imunoexpressão das Hyal 1 e 3 e HAS 1, 2 e 3 nos CCE e ADC. Observamos que a intensidade de expressão de Hyal 3 foi maior pelas células tumorais quando comparada aos controles, porém esta diferença foi marginalmente significante. Já o resultado da análise da freqüência de imunoexpressão das Hyal 1 e 3, e HAS1, 2 e 3 demonstrou expressão na maioria dos espécimes tumorais e controles. A associação entre as variáveis foi testada e evidenciou imunoexpressão concomitante de HYAL e HAS nos tumores. O modelo matemático de sobrevida , controlado para sexo, idade e estadiamento mostrou risco de morte associado com adenocarcinoma sólido e imunoreatividade para HAS2 e HAS3. Para validar os resultados obtidos, sobretudo com a imunoexpressão das Hyal e HAS nos CCE e ADC, estudamos a população de pacientes do Hospital Universitário de Coimbra. Documentamos pela primeira vez uma via pela qual a hiperexpressão de HAS3 e Hyal 3 respectivamente por células epiteliais neoplásicas e mesenquimais, podem favorecer a invasão nos ADC e CCE. Surpreendentemente, demonstramos que a imunoexpressão de HAS1 e 3 pelas células epiteliais neoplásicas confere mais agressividade aos ADC acinares e papilares, mas uma expressão negativa de HAS1 pelas células mesenquimais confere um papel protetor a MEC auxiliando-a a evitar a invasão pelas células tumorais em ambos os tipos subtipos histológicos. A interação entre a expressão das hialuronidades e sintases do àcido hialurônico foi avaliada em relação à expressão de proteínas da transição epitélio-mesênquimal nos tumores de pacientes do Hospital Universitário de Coimbra. Hyal, HAS, E-caderina e TGF- modularam uma via invasiva tumorinduzida nos ADC e CCE de pulmão, e estiveram associados a um espectro diferente de agressividade, uma vez que houve uma relação inversa entre a expressão de biomarcadores epiteliais e mesenquimais. Enquanto a hiperexpressão de HAS1 e HAS3 provê uma agressividade aos CCE e ADC, uma hiperexpressão de TGF- e E-caderina, confere um efeito protetor à MEC ao evitar a invasão por células tumorais em ambos os tipos histológicos. Comparamos os níveis de imunoexpressão das Hyal1 e 3 e HAS 1, 2 e 3 nos tumores ressecados no Hospital das Clínicas e Hospital AC. Camargo com os níveis obtidos em tumores do Hospital Universitário de Coimbra. Verificamos que a imunoexpressão das HAS 1, 2, 3 e Hyal1 foi significativamente maior nos tumores de pacientes do Hospital Universitário de Coimbra, enquanto que a imunoexpressão de Hyal 3 foi significativamente maior nos tumores de pacientes brasileiros. Por todas essas razões, nossos resultados sugerem que estratégias direcionadas à modulação dos níveis de HYAL1-wt e HYAL3-v1, da hiper imuno expressão de HAS3 e Hyal 3 respectivamente por células epiteliais neoplásicas e mesenquimais, da alta síntese de HAS3 e Hyal 1, ou a resposta local baixa de TGF- e E-caderina, poderão ter grande impacto no câncer de pulmão / Given the poor results obtained in the treatment of Lung Cancer, in early stages or locally advanced disease, there is a need to develop molecular markers and immunohistochemical studies that can predict tumor behavior. Hyaluronic Acid (HA) is a component of extracellular matrix is responsible for hydration and maintenance of tissue osmotic equilibrium. Concentrations of HA are elevated in several types of cancers, including lung. Hyaluronidases (HAases) are a family of enzymes involved in the spread of bacterial toxins, poisons and tumor progression. The breakdown of HA into small fragments (3-25 disaccharides) promoted by the action of type HAases Hyal1, Hyal 2 and Hyal 3 is related to the promotion of cancer by inducing angiogenesis and stimulate proliferation through activation of the tyrosine kinase. Some isoforms HAases, described as the product of alternative splicing, have diverse enzymatic activity. The heterogeneity of expression of HAases was identified in some cancers and can be correlated with the different behavior of tumors. In a first instance, the expression profile of Hyal spliced forms was evaluated in tumor and normal lung tissue of 69 tumors resected from patients with adenocarcinomas(ADC) and squamous cell carcinomas (SqCC) from the Hospital das Clínicas and Hospital AC. Camargo. Gene expression of HYAL1 wild-type (wt) and variants 1 to 5 HYAL2-wt, and HYAL3-wt and variants 1 to 3 was identified by PCR and direct sequencing. Different proportions of HYAL3-wt and variants were expressed in tumor and normal lung tissue. HYAL1-wt was associated with unfavorable prognosis and HYAL3-v1 with favorable prognosis. Given the genetic abnormalities found in tumors of patients from Hospital das Clinicas and Hospital AC. Camargo, we continued our research to study the expression of Hyal 1.3 and HAS 1, 2, 3 in squamous cell carcinomas and adenocarcinomas. We observed that the intensity of expression of Hyal 3 was higher in tumor cells compared to controls, but this difference was marginally significant. Since the result of frequency analysis of immunoreactivity of Hyal 1 and 3, and HAS1, 2 e 3 showed expression in the majority of tumor samples and controls. The association between variables was tested and showed concomitant immunoexpression of the HAS and HYAL in tumors. The mathematical model of survival, adjusted for sex, age and staging showed risk of death associated with adenocarcinoma and solid and HAS3 HAS2 immunoreactivity.To validate the results, especially with the immunostaining of Hyal and HAS in squamous cell carcinomas and adenocarcinomas of the lung, the patient population studied at the University Hospital of Coimbra. Documented for the first time a route by which the overexpression of HAS3 and Hyal 3 respectively by neoplastic epithelial and mesenchymal cells may favor the invasion in ADC and SqCC, respectively. Surprisingly, we demonstrated that hyper HAS1 and 3 immunoreactivity by neoplastic epithelial cells confers more aggressiveness to the ADC acinar and papillary, but a negative expression of HAS1 by mesenchymal cells confers a protective role ECM-helping to prevent the invasion by tumor cells in both types histological subtypes.The interaction between the expression of hialuronidades and hyaluronic acid synthases was evaluated for protein expression of epithelial-mesenchymal transition in tumor patients at the University Hospital of Coimbra. Hyaluronidase, hyaluronan synthase, Ecadherin, and TGF- modulated via an invasive tumor-induced in the ADC and SqCC lung, and were associated with a different spectrum of aggressiveness, since there was an inverse relationship between the expression of epithelial biomarkers and mesenchymal cells. While overexpression of HAS1 and HAS3 provides an aggressiveness to SqCC and ADC, an overexpression of TGF- and E-cadherin confers a protective effect by preventing the ECM invasion by tumor cells in both histological types. We compared the levels of immunostaining Hyal 1, 3 and HAS1, 2 and 3 in tumors resected at the Hospital AC. Camargo, and the levels obtained in tumors of the Hospital Universitário de Coimbra. We found that the immunostaining of HAS 1, 2, 3 and Hyal1 was significantly higher in tumors from patients of Coimbra, while Hyal 3 immunoreactivity was significantly. higher in tumors of patients in Brazil. For all these reasons, our results suggest that strategies directed at modulating the levels of HYAL1-wt and HYAL3-v1, the immunohistochemical expression of HAS3 and Hyal 3 respectively by neoplastic epithelial and mesenchymal cells, the synthesis of HAS3 and Hyal1 or the local response of low TGF- and E-cadherin, may have great impact on lung cancer

Les mécanismes adhésifs jouent un rôle crucial en biologie. Les cadhérines classiques constituent une des principales familles d'adhésion cellulaire dépendante du calcium. Ces glycoprotéines transmembranaires sont impliquées dans des interactions principalement homophiles. Ces interactions régulent des voies de signalisation impliquées dans de nombreux phénomènes biologiques. Cette thèse porte sur l'étude comparative des dynamiques d'interactions des cadhérines E- et -11, prototypes respectivement des cadhérines classiques de type I et II. Le ciblage d'acides aminés particuliers de l'interface adhésive nous a permis de montrer que pour les cadhérines de type I, l'échange de brin avec le Trp2 ont un rôle clé ; pour les types II un mécanisme différent intervient. Nous avons aussi développé une chimie innovante pour contrôler l'immobilisation orientée et covalente de protéines. Enfin une revue décrit une étude de l'activation de voies de signalisation par engagement des cadhérines. / Cell adhesion receptors of the classical cadherin family are involved in Ca2+-dependent homophilic interactions. In order to dissect the molecular mechanisms of cadherin-based cellcell adhesion, this Ph.D. thesis describes a comparative dynamic study of interactions between cadherins E- & -11, chosen as classical type I and II cadherins prototypes respectively. Modifications of particular residues in the E-cadherin adhesive interface showed that the ?-strand exchange with its Trp2 had a prominent feature; for type II cadherins, a different mechanism was described involving a larger domain swapping. We then developed a new protocol for immobilizing proteins in an orientated and covalent manner on surfaces. These interactions regulate signalization pathways in various biological processes. Studies describing Stat3 activation through direct cadherin engagement are reviewed.

Weanalyze the mechanical properties of three epithelial/mesenchymal cell lines (MCF-10A, MDAMB- 231, MDA-MB-436) that exhibit a shift in E-, N- and P-cadherin levels characteristic of an epithelial−mesenchymal transition associated with processes such as metastasis, to quantify the role of cell cohesion in cell sorting and compartmentalization. Wedevelop a unique set of methods to measure cell–cell adhesiveness, cell stiffness and cell shapes, and compare the results to predictions from cell sorting in mixtures of cell populations.Wefind that the final sorted state is extremely robust among all three cell lines independent of epithelial or mesenchymal state, suggesting that cell sorting may play an important role in organization and boundary formation in tumours.Wefind that surface densities of adhesive molecules do not correlate with measured cell–cell adhesion, but do correlate with cell shapes, cell stiffness and the rate at which cells sort, in accordance with an extended version of the differential adhesion hypothesis (DAH). Surprisingly, theDAHdoes not correctly predict the final sorted state. This suggests that these tissues are not behaving as immiscible fluids, and that dynamical effects such as directional motility, friction and jamming may play an important role in tissue compartmentalization across the epithelial−mesenchymal transition.

No description available.

Introdução: Adenocarcinomas gástricos múltiplos primários (AGMP) são encontrados em 3,5% a 10% de todos os pacientes com câncer gástrico. A multiplicidade tumoral é amplamente reconhecida como indicador de predisposição genética para o desenvolvimento de neoplasias Além disso, as rotas de carcinogênese não estão claramente definidas nestes tumores (rota mutadora, ou supressora, ou da E-caderina). Objetivo: avaliar a imunoexpressão de hMLH1, hMSH2, e hMSH6 (rota mutadora), p53 (rota supressora) e E-caderina nos AGMP comparando-se com adenocarcinomas únicos (pareados quanto ao sexo, idade, tipo histológico, localização e estádio) e sua relação com dados clínico-patológicos. Casuística: dezenove pacientes com AGMP foram comparados a 21 pacientes com tumores gástricos únicos quanto a características imunohistoquímicas. Métodos: Blocos de tecido fixados em formalina a 10% e incluídos em parafina foram submetidos a cortes histológicos de 4 mm, para as avaliações histológica e imunohistoquímica para hMLH1, hMSH2, hMSH6, p53 e E-caderina. Resultados: A média de idade dos pacientes com AGPM foi de 66 + 9,06 anos, e de 60 + 16,9 anos nos pacientes com tumor único (P=0,56). Vinte e dois tumores estavam localizados na porção distal do estômago; 14, no corpo e cinco na porção proximal. Em 14 pacientes, as lesões eram próximas (< 3 cm), enquanto que, em cinco pacientes, as lesões estavam em outra porção do estômago. O estágio final anatomopatológico pós-operatório foi: 15 no estágio T1 (37,5%) (8 múltiplos e 7 únicos), 7 no estágio T2 (17,5%) (1 múltiplo e 6 únicos), 17 no estágio T3 (42,5%) (9 múltiplos e 8 únicos) e 1 no estágio T4 (27,5%) (1 múltiplo). Segundo a classificação de Laurén, 45 dos tumores foram do tipo intestinal (29 múltiplos e 16 únicos), 16 do tipo gástrico (12 múltiplos e 4 únicos) e um tumor do tipo misto (1 único). O estádio anatomopatológico revelou 30 tumores avançados (16 múltiplos e 14 únicos) e 32 precoces (25 múltiplos e 7 únicos). Na imunohistoquímica, não houve diferença entre a imunoexpressão nos dois grupos de tumores quanto a: hMLH1 (24,3% vs. 19% P=0,64), hMSH6 (4,8% vs. 2,4%, P=0,68), p53 (39% vs. 24%, P=0,35) e E-caderina (27% vs. 19%, P=0,46). hMSH2 foi positivo em todos os casos. Não houve associação entre os imuno-marcadores e os dados clínico-patológicos. Conclusões: 1. As rotas de carcinogênese, mutatora, supressora e E-caderina parecem estar independentemente envolvidas no desenvolvimento dos AGMP; 2. Não houve diferença de imunoexpressão dos marcadores analisados quando compararam-se os AGMP e os tumores únicos. / Introduction: Multiple primary gastric adenocarcinomas (MPGA) have been reported from 3.5% to 10% of all patients with gastric cancer. Tumoral multiplicity is largely known as an indicator of genetic predisposition for the development of neoplasias. Moreover, the route of carcinogenesis has not been clearly clarified in these tumors (mutator pathway or suppressor pathway). Aim: to evaluate the immunoexpression of hMLH1, hMSH2, and hMSH6 (mutator pathway), p53 (suppressor pathway) and E-cadherin in the MPGA, comparing to solitary adenocarcinomas (similar gender, age, histological type, location and staging) and also the relation to the clinicopathological data.: Casuistics: Nineteen patients (Group 1) with MPGA were compared to 21 patients (Group 2) with solitary gastric tumors regarding clinicopathological characteristics and immunohistochemistry. Methods: Blocks of tissue fixed in 10% formalin and embedded in parafin were submitted to 4 mm sections for histological and immunohistochemistry analysis for hMLH1, hMSH2 and hMSH6 (mutator pathway), p53 (suppressor pathway) and E-cadherin. Results: The mean age for the MPGA was 66.8 + 9.06 years, and 59.0 + 16.9 years for the solitary tumor group(P = 0.27). Twenty-two tumors were in the distal stomach, 14 were in the body and five in the proximal portion. In 14 patients the lesions were close to each other (< 3 cm), while in five patients the neoplasias were distant, in another portion of the stomach.The final postoperative pathological stage was: T1 in 15 (eight multiple and seven solitary), T2 in seven (one multiple and six soliatry), T3 in 17 ( nine multiple and eight solitary) and T4 in one ( one multiple). According to the Laurén classification, 45 tumors were intestinal type (29 multiple and 16 solitary), 16 were diffuse (12 multiple and four solitart) and one mixed type ( one solitary). 30 tumors were diagnosed in advanced staging (16 multiple and 14 soliatry) and 32 were early (25 multiple and seven solitary). There was no difference between the hMLH1 immunoexpression in the two groups (24.3% vs. 19%, P=0.64), hMSH6 (4.8% vs. 2.4%, P=0.68), p53 (39% vs. 24%, P=0.35) and E-cadherin (27% v.s 19%, P=0.46). Immunostaining for hMSH2 was positive in all MPGA, indicating absence of alterations of this repair gene marker. There was no association between the immunomarkers and the clinicopathological data. Conclusions: 1. Routes of carcinogenesis, mutator, suppressor, and E-cadherin appear to be involved independently in the development of MPGA; 2. There was no difference in the markers immunoexpression in the two groups.

Introdução: Adenocarcinomas gástricos múltiplos primários (AGMP) são encontrados em 3,5% a 10% de todos os pacientes com câncer gástrico. A multiplicidade tumoral é amplamente reconhecida como indicador de predisposição genética para o desenvolvimento de neoplasias Além disso, as rotas de carcinogênese não estão claramente definidas nestes tumores (rota mutadora, ou supressora, ou da E-caderina). Objetivo: avaliar a imunoexpressão de hMLH1, hMSH2, e hMSH6 (rota mutadora), p53 (rota supressora) e E-caderina nos AGMP comparando-se com adenocarcinomas únicos (pareados quanto ao sexo, idade, tipo histológico, localização e estádio) e sua relação com dados clínico-patológicos. Casuística: dezenove pacientes com AGMP foram comparados a 21 pacientes com tumores gástricos únicos quanto a características imunohistoquímicas. Métodos: Blocos de tecido fixados em formalina a 10% e incluídos em parafina foram submetidos a cortes histológicos de 4 mm, para as avaliações histológica e imunohistoquímica para hMLH1, hMSH2, hMSH6, p53 e E-caderina. Resultados: A média de idade dos pacientes com AGPM foi de 66 + 9,06 anos, e de 60 + 16,9 anos nos pacientes com tumor único (P=0,56). Vinte e dois tumores estavam localizados na porção distal do estômago; 14, no corpo e cinco na porção proximal. Em 14 pacientes, as lesões eram próximas (< 3 cm), enquanto que, em cinco pacientes, as lesões estavam em outra porção do estômago. O estágio final anatomopatológico pós-operatório foi: 15 no estágio T1 (37,5%) (8 múltiplos e 7 únicos), 7 no estágio T2 (17,5%) (1 múltiplo e 6 únicos), 17 no estágio T3 (42,5%) (9 múltiplos e 8 únicos) e 1 no estágio T4 (27,5%) (1 múltiplo). Segundo a classificação de Laurén, 45 dos tumores foram do tipo intestinal (29 múltiplos e 16 únicos), 16 do tipo gástrico (12 múltiplos e 4 únicos) e um tumor do tipo misto (1 único). O estádio anatomopatológico revelou 30 tumores avançados (16 múltiplos e 14 únicos) e 32 precoces (25 múltiplos e 7 únicos). Na imunohistoquímica, não houve diferença entre a imunoexpressão nos dois grupos de tumores quanto a: hMLH1 (24,3% vs. 19% P=0,64), hMSH6 (4,8% vs. 2,4%, P=0,68), p53 (39% vs. 24%, P=0,35) e E-caderina (27% vs. 19%, P=0,46). hMSH2 foi positivo em todos os casos. Não houve associação entre os imuno-marcadores e os dados clínico-patológicos. Conclusões: 1. As rotas de carcinogênese, mutatora, supressora e E-caderina parecem estar independentemente envolvidas no desenvolvimento dos AGMP; 2. Não houve diferença de imunoexpressão dos marcadores analisados quando compararam-se os AGMP e os tumores únicos. / Introduction: Multiple primary gastric adenocarcinomas (MPGA) have been reported from 3.5% to 10% of all patients with gastric cancer. Tumoral multiplicity is largely known as an indicator of genetic predisposition for the development of neoplasias. Moreover, the route of carcinogenesis has not been clearly clarified in these tumors (mutator pathway or suppressor pathway). Aim: to evaluate the immunoexpression of hMLH1, hMSH2, and hMSH6 (mutator pathway), p53 (suppressor pathway) and E-cadherin in the MPGA, comparing to solitary adenocarcinomas (similar gender, age, histological type, location and staging) and also the relation to the clinicopathological data.: Casuistics: Nineteen patients (Group 1) with MPGA were compared to 21 patients (Group 2) with solitary gastric tumors regarding clinicopathological characteristics and immunohistochemistry. Methods: Blocks of tissue fixed in 10% formalin and embedded in parafin were submitted to 4 mm sections for histological and immunohistochemistry analysis for hMLH1, hMSH2 and hMSH6 (mutator pathway), p53 (suppressor pathway) and E-cadherin. Results: The mean age for the MPGA was 66.8 + 9.06 years, and 59.0 + 16.9 years for the solitary tumor group(P = 0.27). Twenty-two tumors were in the distal stomach, 14 were in the body and five in the proximal portion. In 14 patients the lesions were close to each other (< 3 cm), while in five patients the neoplasias were distant, in another portion of the stomach.The final postoperative pathological stage was: T1 in 15 (eight multiple and seven solitary), T2 in seven (one multiple and six soliatry), T3 in 17 ( nine multiple and eight solitary) and T4 in one ( one multiple). According to the Laurén classification, 45 tumors were intestinal type (29 multiple and 16 solitary), 16 were diffuse (12 multiple and four solitart) and one mixed type ( one solitary). 30 tumors were diagnosed in advanced staging (16 multiple and 14 soliatry) and 32 were early (25 multiple and seven solitary). There was no difference between the hMLH1 immunoexpression in the two groups (24.3% vs. 19%, P=0.64), hMSH6 (4.8% vs. 2.4%, P=0.68), p53 (39% vs. 24%, P=0.35) and E-cadherin (27% v.s 19%, P=0.46). Immunostaining for hMSH2 was positive in all MPGA, indicating absence of alterations of this repair gene marker. There was no association between the immunomarkers and the clinicopathological data. Conclusions: 1. Routes of carcinogenesis, mutator, suppressor, and E-cadherin appear to be involved independently in the development of MPGA; 2. There was no difference in the markers immunoexpression in the two groups.

Les infections génitales par les virus du papillome humains (HPV) sont les infections virales sexuellement transmises, les plus communes chez les femmes en âge de procréer. Il est désormais bien établi que l’infection persistante par les HPV classés «à haut risque» est l’un des facteurs indispensables au développement de lésions précancéreuses et cancéreuses du col de l’utérus. Ces HPV semblent aussi être impliqués dans le développement d’autres cancers de la région ano-génitale et pourraient être également impliqués dans les cancers de la tête et du cou. Durant cette dernière décennie, des études croissantes tendent à établir un rôle étiologique des HPV dans les dysfonctionnements gestationnels. La détection des ADN HPV dans les placentas issus d’avortements spontanés et leur capacité exceptionnelle à se répliquer in vitro dans les cellules trophoblastiques cultivées en monocouche, ont apporté de nouvelles perspectives quant à la possibilité que le placenta pourrait constituer aussi un tropisme naturel des infections par HPV.<p>Six jours après la fécondation et suite à l’accolement du blastocyste à l’épithélium utérin, le trophoblaste s’engage dans des processus actifs de prolifération, d’invasion et de différenciation complexe pour la construction de l’interface physiologique indispensable aux échanges essentiels entre la mère et l’enfant ;le placenta. De façon intéressante, ses propriétés sont similaires à celles de la cellule tumorale maligne. Néanmoins, ses mécanismes sont étroitement régulés dans le trophoblaste, à la fois dans l’espace et le temps, assurant un développement normal à chaque étape de la grossesse.<p>Devant toutes ces données, nous avions émis l’hypothèse que l’expression des protéines précoces E5, E6 et E7 d’HPV de type 16 (de haut risque), pourraient modifier le développement des trophoblastes infectés. Les résultats obtenus durant ce travail de doctorat démontrent que la protéine virale E5, hautement hydrophobe, est cytotoxique et affecte la viabilité du trophoblaste. Cette cytotoxicité est neutralisée, et la viabilité est améliorée, lorsque les oncoprotéines majeures E6 et E7 sont exprimées en présence de la protéine E5. Lorsque toutes les protéines précoces sont exprimées sous le contrôle de leur propre promoteur (LCR), la viabilité est favorisée. Ces observations ont été confirmées dans les cellules cervicales également. Il a été précédemment rapporté que les oncoprotéines E6 et E7 affectaient l’adhésion du trophoblaste aux cellules endométriales. Dans le présent travail, il a été retrouvé que la protéine E5 diminuait elle aussi l’adhésion, non seulement aux cellules endométriales, mais aussi au support de culture cellulaire. Les capacités de migration et d’invasion de la matrice extracellulaire sont augmentées par l’expression de E5 et dans une plus large proportion par l’expression de E6 et E7. Des résultats similaires ont été obtenus lorsque toutes les protéines de la région précoces sont exprimées sous le contrôle de leur propre promoteur (LCR). La diminution de l’expression de la E-cadhérine est considérée comme un marqueur de malignité et de mauvais pronostic pour les cancers. Nous avons démontré que l’expression de E5, E6 ou de E7, inhibait l’expression de la E-cadhérine, reflétant l’impact des oncoprotéines du virus HPV-16 sur la diminution de l’adhésion et l’augmentation du pouvoir invasif des cellules trophoblastiques. L’investigation d’autres marqueurs de malignité et de tolérance immunitaire, l’étude de l’impact du virus HPV-6 (de bas risque) sur la migration et l’invasion des cellules trophoblastiques, et l’étude de la capacité des protéines précoces d’HPV-16 à influencer l’entrée des particules virales, ont fait l’objet de résultats préliminaires, ouvrant de larges perspectives.<p><p><p>Genital Human Papillomavirus (HPV) infections are the most common sexually transmitted infections amongst women on the age of reproduction. It is well established that persistent infection with high-risk HPVs is the necessary factor in the causation of precancerous and cancerous cervical lesions. High-risk HPVs have also been reported to be involved in the causation of head and neck cancers and other anogenital cancers. On this last decade, growing data are attempting to study the potential etiological association of HPV with gestational dysfunctions. The detection of HPV DNA in placentas resulting from spontaneous abortions and the unique ability of multiple HPV types to replicate in vitro in trophoblastic cells cultured in a monolayer system, rise new questions over the HPV tropism. <p>Six days following fertilization and once the apposition of the blastocyst on the uterine wall takes place, the trophoblast, in a very active and complex process, starts to proliferate, invade and to differentiate in order to build a physiological interface; the placenta, from where multiple mother/foetus exchanges occur. Interestingly, the way that the trophoblast behaves is very similar to malignant tumoural cells. However, the trophoblast obeys to strict spatial-temporal regulatory confines, insuring a proper development all along the pregnancy.<p>In regard to these data, we hypothesised that the expression of the high-risk HPV type 16 oncoproteins E5, E6 and E7, might modify the development of the infected trophoblast. During my Ph.D study, I demonstrated that the highly hydrophobic protein E5 is localized in many interne membranes compartments of the transfected trophoblast. E5 affects the viability of transiently and stably transfected trophoblastic cells. E6 and E7, favouring cell growth, neutralised the E5 cytotoxic effect. All HPV-16 early proteins, when expressed under the control of their endogenous promoter (LCR), favoured trophoblastic growth. These observations were also observed in cervical cell lines. In addition, E5 decreased the adhesiveness of trophoblastic cells to the tissue culture plastic and to endometrial cells similarly as previously described for E6 and E7. Cells expressing E6, E7 and in less extend E5 favoured chemotaxic migration and matrigel invasion compared to the cells expressing the LacZ control. These effects were also observed when early proteins were expressed under the control of their own viral promoter (LCR). Interestingly, the E-cadherin was down regulated in trophoblastic cells expressing E5, E6 and E7. In conclusion, HPV-16 early proteins enhanced trophoblastic growth and intensify the malignant phenotype by impairing cell adhesion leading to increased cellular motile and invasive properties. HPV-16 E5 participated, with E6 and E7, in these changes by impairing E-cadherin expression, a hallmark of malignant progression. Additional preliminary results consisting on the investigation of other markers of malignancy and immune tolerance, on studying the impact of the low-risk HPV type 6 early proteins on the migratory and invasive properties of trophoblastic cells and on the study of the ability of HPV-16 to influence the entry of virus particules, allowed to open wide perspectives.<p><p><p> / Doctorat en Sciences / info:eu-repo/semantics/nonPublished

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