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Avaliação dos genes envolvidos na transição epitelial-mesenquimal e sua relação com a progressão e a invasão tumoral em câncer de pulmão / Evaluation of genes involved in the epithelial-mesenchymal transition and its relation to tumor progression and invasion in lung cancerRocha, Tabatha Gutierrez Prieto Martins 17 September 2018 (has links)
INTRODUÇÃO: As recidivas e as metástases são os fatores responsáveis pela morte de pacientes com câncer de pulmão (representando 90% dos casos), indicando a necessidade de conhecer as múltiplas vias sinalizadoras envolvidas em sua patogênese, progressão, invasão e metástase. Adenocarcinomas e carcinomas de grandes células invadem primariamente vasos sanguíneos e linfáticos, metastatizando à distância. Já os carcinomas de células escamosas envolvem diretamente o mediastino, sobretudo, linfonodos e pericárdio. Carcinomas neuroendócrinos de baixo grau (carcinoides típicos e atípicos) invadem e metastatizam apesar de serem indolentes, enquanto que carcinomas neuroendócrinos de alto grau (carcinoma neuroendócrino de grandes células e carcinoma de pequenas células), rapidamente metastatizam à distância. Esse espectro diferencial de invasividade nos carcinomas de pulmão ainda não pôde ser definitivamente demarcado por biomarcadores, sobretudo nas variantes neuroendócrinas. Neste aspecto, acredita-se que a EMT esteja mais intimamente envolvida no processo de invasão, despontando como potencial biomarcador. OBJETIVO: Realizar o mapeamento genético da EMT nos carcinomas pulmonares, estabelecendo uma assinatura gênica capaz de prever o potencial de invasão nos diferentes tipos histológicos do câncer de pulmão. MÉTODOS: Espécimes de tumores ressecados cirurgicamente e criopreservados de 60 pacientes foram submetidos a análise de expressão gênica através da qPCR em tempo real, por meio do kit RT2 Profiler PCR array para a EMT com 84 genes de interesse. RESULTADOS: Observou-se a elevada expressão de 24 genes (AKT1, COL1A2, COL3A1, COL5A2, DSP, EGFR, FR11, GSK3B, ILK, ITGA5, ITGAV, ITGB1, JAG1, MAP1B, MMP2, MMP3, SNAI2, SPARC, SPP1, STAT3, TCF3, TGF?3, VPS13A, WNT5A) que participam do processo da EMT e atuam no desenvolvimento da neoplasia pulmonar. Tumores em estádio avançado e com metástases linfonodais apresentaram significante maior expressão dos seguintes genes, COL1A2, COL5A2, DSP, EGFR, FR11, GSK3B, ILK, ITGAV, ITGB1, MAP1B, SNAI2 e VPS13A. Comparando-se carcinomas nãoneuroendócrinos (CEC e AD) e neuroendócrinos (CT, CA, CPPC, CNEGC), observou-se que os neuroendócrinos apresentaram elevada expressão significativa dos genes: FR11, GSK3B, ILK, ITGB1, JAG1, MAP1B e VPS13A. Em relação à sobrevida, a análise univariada demonstrou menor sobrevida para pacientes em estádio avançado do tumor com metástase linfonodal e portador de carcinoma neuroendócrino que apresenta a hiperxpressão de todos os 24 genes da EMT, com exceção dos genes COL3A1 e SPP1. Pela análise multivariada demonstrou-se que pacientes com carcinomas neuroendócrinos com expressão elevada de MMP2 e SPARC apresentaram maior risco de morte (OR 5,41 e 4,94, respectivamente), enquanto que pacientes portadores de carcinomas de células escamosas ou adenocarcinomas com baixa expressão gênica de ILK, SPP1, COL1A2, ITGB1 apresentaram menor risco de morte (OR -7,02; -0,4, -1,3 e -3,02). CONCLUSÃO: Através do presente estudo estabeleceu-se uma assinatura gênica de 24 genes capaz de prever o potencial de agressividade histológica, de invasão e de metástases nos carcinomas pulmonares neuroendócrinos e não-neuroendócrinos / INTRODUCTION: Metastasis are responsible for the death of 90% of patients with lung cancer, indicating the need to know the multiple signaling pathways involved. Adenocarcinomas (Adc) and large cell carcinomas primarily invade blood vessels with distant metastasis, whereas squamous cell carcinoma (SqCC) involves the mediastinal lymph nodes. Neuroendocrine carcinomas of low-grade (typical and atypical carcinoid) are indolent, while high-grade neuroendocrine carcinoma (large cell neuroendocrine carcinoma and small cell carcinoma) metastasize rapidly. Biomarkers of aggressiveness in lung carcinomas remain to be determined, especially in neuroendocrine variants. In these fields, Epithelial to mesenchymal transition (EMT) genes profile emerge promise as an indicator of invasion and metastasis. AIMS: Carry out the genetic mapping of EMT in lung cancer, establishing a gene signature capable of predicting the invasion potential of different histological types of lung cancer. METHODS: Were included specimens of 60 patients and the EMT gene expression was quantified with a quantitative real-time (RT)- PCR carried out on StepOnePlus(TM) Real-Time PCR System (Applied Biosystems) with RT2 Profiler PCR Array System for the EMT pathway wih 84 target genes. (Qiagen, Dusseldorf, Germany). Associations of the gene signature and clinicopathological features, as well as prognostic factors were evaluated. RESULTS: Was observed high expression of 24 genes (AKT1, COL1A2, COL3A1, COL5A2, DSP, EGFR, FR11, GSK3B, ILK, ITGA5, ITGAV, ITGB1, JAG1, MAP1B, MMP2, MMP3, SNAI2, SPARC, SPP1, STAT3, TCF3, TGFbeta3, VPS13A, WNT5A) that are involved in the EMT process and act in the development of pulmonary neoplasia. Tumors at the advanced stage and with lymph node metastasis shown a significant higher expression of the genes COL1A2, COL5A2, DSP, EGFR, FR11, GSK3B, ILK, ITGAV, ITGB1, MAP1B, SNAI2 and VPS13A. Comparing the histological subtypes non-neuroendocrine (SqCC and AD) and neuroendocrine carcinomas (TC, AT, SCLC, LCNEC), was observed that the neuroendocrine variant shown a higher significant expression of the genes FR11, GSK3B, ILK, ITGB1, JAG1, MAP1B and VPS13A. Regarding survival, univariate analysis showed lower survival for patients in the advanced tumor stage, with lymph node metastasis and with neuroendocrine carcinoma histology that presenting overexpression for all 24 EMT genes, with the exception of the COL3A1 and SPP1 genes. Cox regression controlled by, histological types and gene expression of ILK, MMP2, SPP1, SPARC, COL1A2 and ITGB1 showed that patients with neuroendocrine carcinomas with higher expression of MMP2 and SPARC had a higher risk of death (OR 5.41 and 4.94, respectively), whereas patients with squamous cell carcinomas or adenocarcinomas with lower gene expression of ILK, SPP1, COL1A2, ITGB1 showed lower risk of death (OR -7.02, -0.4, -1.3 and -3.02). CONCLUSION: Was established a potential gene signature of 24 genes involved in the EMT process and capable of predicting the histological aggressiveness, invasion and metastasis in neuroendocrine and non-neuroendocrine variants of lung carcinomas
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Estudo dos genes e microRNAs relacionados à transição epitélio-mesenquimal no adenocarcinoma de próstata / Study of gene and miRNA expression profiles related to epithelial-mesenchymal transition in prostate adenocarcinomaKatz, Betina Stifelman 28 May 2014 (has links)
Introdução: O câncer de próstata (CaP) é o tumor mais comum em homens e a segunda causa de óbito por câncer no Brasil. Com a adoção do rastreamento, a maioria dos pacientes apresenta doença localizada ao diagnóstico, enquanto apenas 4% têm doença metastática. Um dos principais mecanismos responsáveis pela progressão tumoral é a transição epitélio-mesenquimal (TEM). Esse é um programa celular reversível no qual a célula epitelial perde a capacidade de aderência intercelular e assume um fenótipo mesenquimal com potencial invasivo e metastático. A principal característica da TEM é a repressão da E-caderina através de fatores de transcrição que incluem ZEB1, ZEB2, Snail, Slug e Twist1. Os microRNAs também estão envolvidos na regulação do processo, sendo a família do miR-200 uma das mais importantes e uma potente indutora da diferenciação epitelial. Assim sendo, o conhecimento dos fatores envolvidos na TEM no CaP é fundamental para a compreensão do comportamento biológico dessa neoplasia. Objetivos: Analisar a expressão dos genes e microRNAs envolvidos na transição epitélio-mesenquimal em espécimes de câncer de próstata localizado e em linhagens celulares de câncer de próstata metastático. Além disso, correlacionar o perfil de expressão dos genes e microRNAs com parâmetros clínico-patológicos. Material e métodos: O estudo consistiu na análise de espécimes de 51 pacientes com CaP localizado tratados por prostatectomia radical e de linhagens celulares de CaP metastático (LNCaP, DU145 e PC3). O grupo controle foi composto por 10 casos de hiperplasia prostática benigna. A expressão dos genes E-caderina, N-caderina, Vimentina, TGF-beta1, ZEB1, ZEB2, Snail, Slug, Twist1 e PDGF-D e dos microRNAs 200a, 200b, 200c, 429, 141, 203, 205, 183, 373, 21, 9, 1, 495, 29b, 30a, 34a, 155 e 10b foi avaliada através da técnica de PCR em tempo real (qRT-PCR) nos espécimes e nas linhagens. Para correlação com parâmetros clínico-patológicos, os pacientes foram divididos em grupos em relação ao escore de Gleason, estadiamento patológico, PSA pré-operatório, recorrência bioquímica e doença de baixo e alto risco. Para avaliação do tumor metastático, agrupamos as linhagens celulares e comparamo-las com tumores pT3. Resultados: A grande maioria dos casos apresentou superexpressão de E-caderina e Twist1 e subexpressão de N-caderina, Vimentina, TGF-beta1, ZEB1 e Slug. ZEB2, Snail e PDGF-D apresentaram expressão variável. A família do miR-200 e os miRNAs 203, 205, 183, 373 e 21 apresentaram superexpressão, enquanto que os miRNAs 9, 495, 29b e 1 apresentaram subexpressão. Os demais miRNAs apresentaram perfil de expressão variável. Níveis menores de expressão dos miRNAs 200b, 30a e 1 associaram-se significativamente com estadiamento patológico. Os pacientes com expressão reduzida do miR-200b também apresentaram associação com escore de Gleason >= 8 e com menor tempo de sobrevida livre de recorrência bioquímica. Ainda, níveis baixos do miR-30a e níveis elevados de Vimentina e Twist1 associaram-se com grupo de alto risco. As linhagens metastáticas apresentaram níveis de expressão do miR-183 e do Twist1 significativamente maiores quando comparadas ao tumor localizado. Conclusão: O CaP localizado mantém um fenótipo molecular epitelial. Menor expressão dos miRNAs 200b, 30a e 1 está associada com estadiamento mais avançado, sendo que o miR-200b também associou-se com maior escore de Gleason e menor tempo de sobrevida livre de recorrência bioquímica, e o miR-30a, com grupo de alto risco. A maior expressão de Vimentina e Twist1 apresentou associação com o grupo de alto risco. miR-183 e Twist1 apresentam maiores níveis de expressão em linhagens celulares metastáticas em relação ao tumor primário. De acordo com nossos resultados, os miRNAs 200b, 30a, 1 e 183 e os genes Twist1 e Vimentina podem ter um papel importante na progressão do CaP, além de serem potenciais marcadores prognósticos / Introduction: Prostate cancer (PCa) is the most common cancer in men and the second leading cause of cancer-related mortality in Brazil. After the adoption of screening, most patients present with localized disease at the time of diagnosis, while only 4% have metastatic disease. One of the main mechanisms of tumor progression is the epithelial-mesenchymal transition (EMT). This is a reversible cell-biological program in which an epithelial cell loses intercellular adhesion and acquires a mesenchymal phenotype with invasiveness and metastatic potential. The main event in EMT is the repression of E-cadherin by transcriptional factors, including ZEB1, ZEB2, Snail, Slug, and Twist1. microRNAs are also involved in the regulation of this process, and one of the most important ones is the miR-200 family, which is a powerful inducer of epithelial differentiation. Therefore, the knowledge of the factors involved in EMT in PCa is essential to understand the biological behavior of this neoplasia. Objectives: Analysis of gene and miRNA expression involved in epithelial-mesenchymal transition in specimens of localized prostate cancer and metastatic prostate cancer cell lines. Correlation between the gene and miRNA expression profiles and clinicopathological features. Material and Methods: This study consisted in the analysis of specimens from 51 patients with localized PCa treated by radical prostatectomy and of metastatic PCa cell lines (LNCaP, DU145, PC3). The control group was composed by 10 cases of benign prostatic hyperplasia. Gene expression of E-cadherin, N-cadherin, Vimentin, TGF-beta1, ZEB1, ZEB2, Snail, Slug, Twist1, and PDGF-D as well as miRNA expression of 200a, 200b, 200c, 429, 141, 203, 205, 183, 373, 21, 9, 1, 495, 29b, 30a, 34a, 155, and 10b were assessed by Real-Time PCR (qRT-PCR). The patients were divided into groups according to Gleason score, pathological stage, preoperative PSA, biochemical recurrence, and low and high-risk disease. For evaluation of metastatic tumor, the cell lines were grouped and compared to pT3 tumors. Results: The vast majority of the cases showed overexpression of E-cadherin and Twist1 and underexpression of N-cadherin, Vimentin, TGF-beta1, ZEB1, and Slug. ZEB2, Snail, and PDGF-D showed a variable expression pattern. miRNA-200 family and miRNAs 203, 205, 183, 373, and 21 were overexpressed, while miRNAs 9, 495, 29b, and 1 were underexpressed. The remaining miRNAs showed a variable expression pattern. Lower expression levels of miRNAs 200b, 30a, and 1 were significantly associated with pathological stage. Patients with lower expression of miR-200b also showed association with Gleason score >= 8 and biochemical recurrence-free survival (BRFS). Furthermore, low expression levels of miR-30a and high expression levels of Vimentin and Twist1 were associated with high-risk group. The metastatic PCa cell lines showed significantly higher expression levels of miR-183 and Twist1 in comparison to the primary tumor. Conclusion: Localized prostate cancer maintains a molecular epithelial phenotype. Lower expression of miRNAs 200b, 30a, and 1 was associated with higher stage. Low levels of miR-200b were also associated with high Gleason score and shorter BRFS, and miR-30a, with high-risk group. High expression levels of Vimentin and Twist1 were associated with high-risk group. miR-183 and Twist1 levels were higher in metastatic cell lines than in the primary tumor. According to our results, miRNAs 200b, 30a, 1, and 183 and the genes Twist1 and Vimentin might play an important role in the progression of PCa and may turn to be important prognostic markers
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Estudos proteômicos da transição epitélio-mensenquimal induzida por TGF-β e EGF em linhagens celulares de câncer de pâncreas / Proteomics studies of epithelial mesenchymal transition induzed By TGF-β and EGF in pancreatic cancer cell linesCanchaya, Gabriela Norma Solano 07 July 2016 (has links)
O câncer de pâncreas é considerado um dos adenocarcinomas mais agressivos, ocupando o quarto lugar de mortes devidas a câncer, isto é dado principalmente a seu desenvolvimento silencioso e a sua complexidade genética, tornando-o de difícil detecção. Consequentemente, o diagnóstico desta doença ocorre apenas em fase tardia, quando o tratamento é apenas para fins paliativos. As anomalias genéticas mais frequentes no câncer de pâncreas invasivo estão relacionadas à ativação por mutações do gene KRAS e à inativação dos genes supressores de tumor CDKN2A, TP53, SMAD4 e BRCA2. Além destas conhecidas vias de sinalização, fatores de crescimento como o TGF-? e EGF também apresentam papel fundamental na progressão e metástase do câncer de pâncreas. Interessantemente, TGF-? e EGF são também indutores do processo denominado transição epitelial-mesenquimal (EMT), onde células epiteliais normais, durante a embriogênese, ou células cancerosas durante a progressão tumoral e metástase, perdem seus contatos intracelulares e adquirem caráter migratório. Desta forma a EMT, induzida por altos níveis de TGF-? e/ou EGF, é considerada como um dos mecanismos de progressão tumoral em adenocarcinomas. No presente estudo, foram estudados os proteomas e o fosfoproteoma da EMT do PanCa. Assim, células de câncer de pâncreas PANC- 1 foram induzidas à EMT em cultura com os fatores de crescimento TGF-?1 ou TGF-?2 e EGF, e após a indução, marcadores moleculares e propriedades funcionais de migração e invasão foram confirmados. Duas condições de indução da EMT foram estabelecidas, para as quais foram desenvolvidas as análises proteômicas quantitativas. A abordagem foi baseada em marcação isotópica de células em cultura (SILAC), em conjunto com fracionamento celular e de proteínas intactas, e cromatografia líquida acoplada à espectrometria de massas para identificação de proteínas em larga escala. No total, aproximadamente 5.000 proteínas foram identificadas, e a maioria delas quantificadas com precisão nas duplicatas experimentais. Foram selecionadas 37 proteínas com expressão diferencial estatisticamente significativa nos experimentos proteômicos, as quais participam principalmente em processos de biogênese, adesão e apoptóticos. A análise de redes de interação revelou que as proteínas alteradas estavam principalmente localizadas em vias de sinalização que controlam processos de organização da matriz extracelular, splicing alternativo e regulação da apoptose. A análise do fosfoproteoma foi feita usando TGF-?1 como agente indutor da EMT nas células PANC-1, usando a estratégia ERLIC para o enriquecimento de fosfopeptídeos. No total, foram identificados 5.965 fosfopeptídeos não redundantes, correspondendo a um total de 2.250 fosfoproteínas analisadas, sendo quantificadas 2.053 ao menos em duas replicatas, e destas foram identificados 61 fosfopeptídeos regulados pertencentes a 55 fosfoproteínas, relacionados com processos de regulação do mRNA e vias de sinalização ligadas à adesão celular. Em conclusão, nosso estudo elucida potenciais novos alvos para inibição da EMT, controle da metástase, ou para auxiliar no diagnóstico da doença, quando devidamente validada. / Pancreatic cancer kills more than 200 thousand people worldwide every year. Also, pancreatic cancer is considered one of the most aggressive adenocarcinomas and difficult to diagnose since it develops silently and presents a high genetic complexity. Consequently, the diagnostic is often late, when the pancreatic cancer has already metastasized and the treatment has only palliative purposes. The most frequent genetic alterations observed in pancreatic cancer are related to mutations in KRAS oncogene and CDKN2A, TP53, SMAD4 and BRCA2 tumor suppressor genes. In addition to these known frequent mutations, growth factors such as TGB- ? and EGF play important roles in pancreatic cancer progression and metastasis. Interestingly, TGB- ? and EGF are also inducers of the Epithelial to Mesenchymal Transition (EMT), in which epithelial cells lose their intracellular contacts and acquire migratory capacities. Therefore, EMT is considered one of the mechanisms responsible for tumor progression and metastasis in adenocarcinomas in addition of being correlated to the process of generating cancer stem cells. In our present study, pancreatic cancer cell line PANC-1 was induced to EMT by using growth factors TGF-?1 or TGF-?2 and EGF. Both molecular and functional properties, such as invasion and migration, were evaluated in PANC-1 cells undergoing EMT and confirm the induction. Two conditions of EMT induction were properly established and in-depth quantitative proteomic analysis based on stable isotope labeling in cell culture (SILAC) followed by cellular and protein fractionation were assessed. In total, 5.000 proteins were identified and most of them were accurately quantified in duplicate experiments. Thirty-seven proteins were selected as differentially expressed with statistical significance, and were related mainly with biogenesis, adhesion and apoptosis processes. Interaction network analysis showed that regulated proteins were predominantly participating in signaling pathways linked to extracellular matrix organization, alternative splicing and apoptosis regulation. Phosphoproteome analysis was done using TGF-?1 as EMT-inductor agent on PANC-1 cells and ERLIC strategy for phosphopeptides enrichment. In total, were identified 5.965 non-redundant phosphopeptides corresponding to approximately 2.250 analyzed phosphoproteins, thereof 2.053 were quantified in at least two replicates. At comparison, were identified 61 regulated phosphopeptides belonging to 55 phosphoproteins, which were related with mRNA regulation processes and signialing pathways linked to cellular adhesion. In conclusion, our study highlighted potential new targets for EMT inhibition, metastasis control or to help in pancreatic cancer diagnosis, when careful validated.
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A study of an epithelial-mesenchymal transition-inducing transcriptional factor Snail in prostate cancer using a newly-developed three-dimensional culture model. / CUHK electronic theses & dissertations collectionJanuary 2008 (has links)
In recent years, three dimensional (3D)-culture technique has emerged as a very popular approach to reconstruct tissue architectures and develop experimental models for studying epithelial cancers. However, 3D culture models of prostate epithelial cells to mimic prostate cancer development are relatively rare, making it highly desirable to develop and characterize novel 3D culture models suitable for studying prostate cancer. Recently, epithelial-mesenchymal transition (EMT) has emerged as an important mechanism for cancer cell invasion. The zinc finger transcriptional factor Snail as a key regulator of EMT has been found to contribute to aggressive progression in many types of neoplasms. Even though several studies corroborated that EMT is implicated in prostate cancer, the expression patterns of Snail in normal prostate and prostate cancer, and the functional role of Snail in prostate cancer as well as its relation with EMT are still unknown. Based on this background, my major efforts were to establish a 3D culture model of human prostatic epithelial cells with structural and functional relevance to prostate gland and to employ this model to study the functional role of Snail in the prostate cancer. / When embedded in Matrigel for 3D culture, BPH-1 cells developed into growth-arrested acinar structures with a hollow lumen. Ultrastructural examination of BPH-1 spheroids by electricon microscopy indicated that BPH-1 spheroids displayed a polarized differentiation phenotype. Immunoflurescence analysis of polarized epithelial markers further confirmed that BPH-1 spheroids were polarized. In contrast, tumorigenic BPH-1CAFTD cells exhibited disorganized and continuously proliferating structures in Matrigel, with polarized epithelial markers randomly diffused or completely lost. In addition, BPH-1 CAFTD cells displayed significantly higher invasive capacity in comparison to BPH-1 cells by transwell invasion assay. Moreover, LY294002 treatment of BPH-1CAFTD1 and BPH-1CAFTD3 cells in 3D cultures resulted in impaired cell proliferation as evidenced by reduced colony size and decreased Ki-67 index, and western blot analysis showed that cyclin D1 protein levels were significantly decreased, while p21 protein levels were slightly up-regulated in LY294002-treated 3D cultures. Additionally, LY94002 significantly decreased the invasive capacity of BPH-1CAFTD1 and BPH-1CAFTD3 cells. Interestingly, LY294002 treatment completely reverted the disorganized non-polar 3D structures of BPH-1CAFTD1 cells to well-organized polarized spheroid structures in Matrigel, but failed to restore the polarized differentiation in 3D cultures of BPH-1CAFTD3 cells, which still formed compact aggregates as shown by confocal immunofluorescence analysis. Snail protein was barely detected in the epithelial cells of human benign prostatic tissue but significantly elevated as nuclear protein in primary prostate cancer and bone metastatic specimens by immunohistochemical analysis. Snail transcript levels were weakly expressed in a majority of nonmalignant prostatic epithelial cell lines, while markedly increased in almost all tested cancer cell lines. Snail expression induced a morphological switch to more scattered and spindle-shaped appearance in BPH-1 and BPH-1CAFTD1 cells in 2D culture, and immunofluorescence analysis of several EMT specific markers indicated that Snail-expressing cells underwent EMT. In 3D contexts, Snail-expressing cells developed into more disorganized structures with many cords or protrusions, with a concurrent EMT change as evidenced by reduced E-cadherin and increased vimentin expression. In addition, Snail expression augmented the invasive capacities in both BPH-1 cells and BPH-lCAFTD1 cells, but did not significantly affect the migratory capacities. Snail expression enhanced the MMP2 activity in BPH-1 cells and promoted both MMP-2 and MMP-9 activities in BPH-1CAFTD1 cells. Moreover, Snail expression enhanced anchorage-independent growth capability in BPH-1 cells, but failed to initiate tumor formation in nude-mice. Lastly, Snail expression induced a dramatic increase in FoxC2 and SPARC transcripts but a marked decrease in claudin-1 and p63 transcripts. / Chu, Jianhong. / Adviser: Franky Chan Leung. / Source: Dissertation Abstracts International, Volume: 70-06, Section: B, page: 3448. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2008. / Includes bibliographical references (leaves 143-166). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Electronic reproduction. [Ann Arbor, MI] : ProQuest Information and Learning, [200-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstracts in English and Chinese. / School code: 1307.
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Estudo da frequência relativa e participação de subpopulações de células-tronco de câncer no processo de metástase em carcinoma epidermóide de boca / Study of the relative frequency and participation of cancer stem cells subpopulations in the process of metastasis of oral squamous cell carcinomaLopes, Nathália Martins 18 November 2016 (has links)
A presença de metástase em linfonodos cervicais é o fator prognóstico mais importante para o carcinoma epidermóide de boca (CEB), uma das neoplasias malignas mais comuns da região de cabeça e pescoço. Estudos têm associado os mecanismos de progressão tumoral, recorrência e metástase com a presença e manutenção de células-tronco de câncer (CSC, do inglês cancer stem cells), que correspondem à subpopulação celular mais migratória e altamente metastática quando comparada com outras subpopulações presentes no tumor. Ainda, evidências recentes mostram que há uma ligação entre as CSC e o processo de transição epitélio-mesenquimal (EMT, do inglês epithelial-mesenchymal transition), evento em que as células perdem a polaridade e a aderência célula-célula e exibem uma morfologia mesenquimal, o que as permite migrar além do tumor primário. Portanto, o objetivo deste estudo foi de avaliar, in vitro, a associação das propriedades biológicas relacionadas ao fenótipo tronco tumoral e de transição epitélio-mesenquimal, com o comportamento invasivo e metastático das linhagens SCC-9 de CEB primário e metastático correspondente. Para este fim, linhagens celulares parental (SCC-9 ZsGreen) e metastática (SCC-9 ZsGreen LN-1), obtidas após ensaios de tumorigênese in vivo, foram caracterizadas em relação à capacidade de proliferação e migração, bem como à presença e proporção da subpopulação de CSC, baseado na capacidade de formação de colônias tumorais, preferencialmente holoclones, e de esferas tumorais. Ensaios de expressão gênica (qRT-PCR) também foram conduzidos para se verificar os níveis de expressão diferencial dos marcadores de CSC (CD44, BMI1, ALDH1 e p75NTR), bem como de EMT (SNAIL1, TWIST1, AXL, vimentina, E-caderina e N-caderina) em ambas as linhagens tumorais, utilizando-se células epiteliais de palato humano (CEPH) como controle. Tanto a capacidade de proliferação e migração celular, quanto a quantidade de holoclones e esferas tumorais, foram significativamente maiores na linhagem metastática quando comparada com a parental. A linhagem metastática SCC-9 ZsGreen LN1 exibiu, ainda, superexpressão estatisticamente significante de CD44, BMI-1, AXL, vimentina e N-caderina e baixa expressão de E-caderina, quando comparadas com a linhagem parental. O potencial metastático de SCC-9 ZsGreen LN-1 parece ser uma consequência da sua maior quantidade de subpopulação com fenótipo de CSC que, ainda, passou pelo processo de EMT. Portanto, sugere-se que as propriedades biológicas relacionadas à capacidade metastática da linhagem SCC-9 ZsGreen LN-1 parecem estar relacionadas a ambos os fenótipos tronco tumoral e de transição epitélio-mesenquimal. / The presence of metastasis in cervical lymph nodes is the most significant prognostic factor for the oral squamous cell carcinoma (OSCC), one of the most common malignant neoplasms of the head and neck. Studies have associated the mechanisms of tumor progression, recurrence and metastasis with the presence and maintenance of cancer stem cells (CSC), which correspond to the most migratory and highly metastatic cellular subpopulation when compared to other cell subpopulations within the tumor. Moreover, recent evidence shows that there is a link between the CSC and the process of epithelial-mesenchymal transition (EMT), an event in which the cells lose their polarity and cell-cell adhesion and exhibit a mesenchymal morphology, which allows them to migrate beyond the primary tumor. Thus, the purpose of the present study was to evaluate, in vitro, the combination of the biological properties related to CSC and EMT phenotypes with the invasive and metastatic behavior of the corresponding primary and metastatic OSCC SCC-9 cell line. For this, parental (SCC-9 ZsGreen) and metastatic (SCC-9 ZsGreen LN-1) OSCC cell lines, obtained after in vivo tumorigenesis assays were characterized regarding the ability of proliferation and migration, as well as the presence and proportion of CSC subpopulation, based on the capacity of generating tumor colonies, preferably holoclones, and tumor spheres. Gene expression assays (qRTPCR) were also conducted to verify the differential expression levels of CSC markers (CD44, BMI-1, ALDH-1 and p75NTR) and EMT (SNAIL1, TWIST1, AXL, vimentin, Ecadherin and N-cadherin) markers in both tumor cell lines, using human palate epithelial cells (HPEC) as control. Both proliferation and cell migration capacity, as well as the numbers of holoclones and tumor spheres were significantly higher in metastatic cell line compared to the parental. Furthermore, the metastatic cell line SCC-9 ZsGreen LN-1 showed significantly higher expression of CD44, BMI-1, ALDH- 1, vimentin, and N-cadherin and lower expression of E-cadherin, when compared to parental cell line. The metastatic potential of SCC-9 ZsGreen LN-1 seems to be a consequence of the greater amount subpopulation with CSC phenotype that also underwent the EMT process. Therefore, it is suggested that the biological properties related to metastatic ability of SCC-9 ZsGreen LN-1 cell line are related to both CSC and EMT phenotypes.
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Avaliação de marcadores relacionados à transição epitélio-mesênquima na endometriose pélvica / Evaluation of markers related to epithelial-mesenchymal transition in the patients with pelvic endometriosisAna Carolina Machado Poppe 10 December 2013 (has links)
Introdução: A endometriose é uma doença ginecológica comum caracterizada pela presença de estroma e/ou glândula endometrial fora da cavidade uterina, e que não possui sua etiopatogenia bem estabelecida. A transição epitélio-mesênquima (TEM) é um processo que consiste em uma série de mudanças no fenótipo de células epiteliais que fazem com que estas células assumam características de células mesenquimais. Assim como observado na TEM, as células endometriais no contexto da endometriose apresentam capacidade migratória, invasibilidade e elevada resistência à apoptose. As moléculas de adesão têm adquirido crescente relevância na TEM, pois relacionam-se à perda de adesão célula-célula com o aumento da invasão e metástase. O objetivo deste estudo foi investigar a expressão de marcadores relacionados com a TEM na endometriose superficial, ovariana e profunda. Pacientes e Métodos: Foram selecionadas 103 mulheres que preenchiam os critérios de inclusão estabelecidos, constituindo 2 grupos de estudo independentes entre si: 18 mulheres com endometriose peritoneal, ovariana e profunda concomitantes; 85 mulheres com endometriose ovariana e/ou profunda, dividido em 44 mulheres com endometriose ovariana e 41 com endometriose intestinal. Através de reações de imunoistoquímica, a expressão proteica dos marcadores e-caderina, n-caderina, betacatenina, receptor de estrogênio e receptor de progesterona foram avaliados nos tecidos de interesse em cada grupo de estudo. Além dos locais de doença, as mulheres foram avaliadas quanto à relação com a fase do ciclo e à classificação histológica da doença. Resultados: As lesões de endometriose de ovário mostraram uma menor expressão de n-caderina em comparação às lesões de intestino e peritônio (p=0,032). O receptor de estrogênio e receptor de progesterona se mostraram significativamente menos expressos no componente epitelial da doença de ovário do que no epitélio da endometriose de peritônio e intestino (p=0,002; p=0,48). A expressão da n-caderina apresentou uma correlação direta com a expressão do receptor de estrogênio no estroma da endometriose de intestino (p=0,036). Conclusão: Estes resultados sugerem que a transição epitélio-mesênquima esteja envolvida na etiopatogenia da endometriose, demonstrando que a doença de ovário se comporta de maneira diferente da doença superficial e da doença infiltrativa profunda, sendo a n-caderina um importante fator envolvido neste processo possivelmente influenciada pela ação do estrogênio / Background: Endometriosis is a common gynecological disease defined as the presence of ectopic endometrial glands and stroma outside the uterine cavity, and its pathogenesis is not well established. The epithelial to mesenchymal transition (EMT) is a process consisting of a series of changes in the phenotype of epithelial cells that make these cells assume the characteristics of mesenchymal cells. As observed in the EMT, endometrial cells in the context of endometriosis have the capacity of migration, invasiveness and high resistance to apoptosis. . The adhesion molecules have become progressively relevant in EMT, in view of the cell-to-cell adhesion loss, with increased invasion and metastasis. The goal of this study was to investigate the expression of markers related to EMT in superficial, ovarian and deep endometriosis. Patients and Methods: 103 women were selected who met the inclusion criteria, constituting two independent study groups: 18 women with peritoneal, ovarian and deep concomitant endometriosis, 85 women with ovarian and / or deep endometriosis, divided in 44 women with ovarian endometriosis and 41 with intestinal endometriosis. Through immunohistochemical reactions, the protein expression of e-cadherin, ncadherin, beta-catenin, estrogen receptor and progesterone receptor markers were evaluated in tissues of interest in each study group. In addition to the sites of the disease, menstrual phase and histological classification (well-differentiated, undifferentiated, mixed pattern and stromal) of the disease were recorded. Results: The ovarian endometrisis showed less n-cadherin marker than lesions of the peritoneum and bowel (p=0,032). Ovarian endometriosis also showed markedly decreased expression of estrogen and progesterone receptors in epithelial cells, compared with peritoneal and deep endometriosis (p=0,002; p=0,48). The expression of N-cadherin showed a direct correlation with estrogen receptor expression in the stroma of bowel endometriosis (p = 0.036). Conclusion: These results suggest that epithelial to mesenchymal transition involved in the pathogenesis of endometriosis, demonstrating that the ovary disease behaves differently disease than peritoneal and deep disease, so that the n-cadherin is an important factor involved in this process, possibly influenced by the action of estrogen
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Perfil de expressão das metaloproteinases de matriz (MMPs) e seus inibidores (TIMPs e RECK) em tumores odontogênicos benignos / Expression profile of matrix metalloproteinases (MMPs) and their inhibitors (TIMP and RECK) in odontogenic tumors benignFábio César Prosdócimi 06 February 2013 (has links)
Os tumores odontogênicos benignos compreendem um grupo de neoplasias originárias dos tecidos dentários. Pesquisas vêm buscando identificar moléculas envolvidas nos mecanismos moleculares que regulam a remodelação da matriz extracelular (MEC) e como isto influencia no comportamento localmente invasivo presente em alguns destes tumores. A Transição Epitélio-Mesenquimal (TEM conversão do fenótipo epitelial em mesenquimal) é bem caracterizada em diversos carcinomas, culminando em mestástase. MMPs são enzimas que degradam os componentes da MEC, geram moléculas bioativas, participam da TEM e o controle da remodelação da MEC dá-se pelo balanço entre elas, seus inibidores (TIMPs e RECK) e seu ativador (EMMPRIN). Assim, o objetivo deste trabalho foi delinear o perfil de expressão das MMPs (-2, -7, -9 e -14), seus inibidores (TIMPs -2, -3, -4 e RECK), seu ativador (EMMPRIN) e marcadores da TEM (Snail, Slug, N-caderina, Fibronectina, a-Actina de músculo liso e Vimentina) em Ameloblastomas (AB) e Tumores Odontogênicos Cístico Calcificantes (TOCC). Ainda, realizamos a comparação da expressão de cada molécula avaliada em cada compartimento celular (epitélio e estroma) e correlação entre as moléculas avaliadas no mesmo tumor. Utilizamos 19 casos de AB e 18 casos de TOCC (Serviço de Anatomia Patológica da FOUSP), localização das enzimas/proteínas por imunoistoquímica e analisadas nos compartimentos epitelial e estromal. Todas as proteínas/enzimas analisadas foram detectadas tanto nos AB quanto nos TOCC, sendo a maioria expressa em ambos os compartimentos. A N-caderina foi localizada apenas no epitélio dos AB e a Vimentina somente no estroma em ambos os tumores. Na comparação entre o epitélio x estroma dos ameloblastomas, verificamos que houve diferença estatisticamente significante (p<0,05) para a MMP-2, MMP-7, EMMPRIN/CD147, Fibronectina, a-Actina de músculo liso, N-caderina, Vimentina, Snail e Slug. Na comparação entre o epitélio x estroma dos TOCC, verificamos que houve diferença estatisticamente significante (p<0,05) para a MMP-9, RECK, EMMPRIN/CD147, Vimentina, N-caderina, Snail e Slug. Assim, entre o epitélio x estroma dos ameloblastomas e TOCC, verificamos que houve diferença estatisticamente significante (p<0,05) para a MMP-2, MMP-7, MMP-9, RECK, EMMPRIN/CD147, Fibronectina, Vimentina, a-Actina de músculo liso, N-caderina, Snail e Slug. Esta é a primeira vez que a EMMPRIN, RECK, TIMP-3, TIMP-4, Ncaderina, Snail e Slug são descritas em TOCC e TIMP-3, TIMP-4, Snail e Slug em ameloblastomas. Concluímos que estas proteínas/enzimas estão diferencialmente expressas tanto no epitélio quanto no estroma destes tumores e sugerimos que estes podem participar do comportamento localmente invasivo. / Odontogenic tumors comprise a group of benign neoplasms originating from dental tissues. Research looking for identify molecules involved in the molecular mechanisms that regulate extracellular matrix remodeling (ECM) and how this impacts on locally invasive behavior present in some of these tumors. Epithelial-Mesenchymal Transition (EMT - conversion of epithelial phenotype into mesenchymal phenotype) is well characterized in several carcinomas, leaving to metastasis. MMPs are enzymes that degrade ECM components, generate bioactive molecules, participating in the EMT and control ECM remodeling is given by the balance between them, their inhibitors (TIMPs and RECK) and its activator (EMMPRIN). The aim of this study was evaluate expression profile of MMPs (-2, -7, -9 and - 14), their inhibitors (TIMPs -2, -3, -4 and RECK), its activator (EMMPRIN) and EMT markers (Snail, Slug, N-cadherin, Fibronectin, -smooth muscle actin and Vimentin) in ameloblastomas (AB) and Calcifying Cystic Odontogenic Tumor (CCOT). We also compared the expression of each molecule assessed in each cellular compartment (epithelium and stroma) and correlation between molecules evaluated in the same tumor. We used 19 AB cases and 18 CCOT cases from files of Pathology Laboratory (FOUSP), localization of enzymes/proteins and analyzed by immunohistochemistry in epithelial and stromal compartments. All proteins/enzymes were detected in both AB and CCOT, mostly expressed in both compartments. N-cadherin was localized only in the epithelium of AB and Vimentin only in stromal in both tumors. Comparing \"epithelium vs stroma\" of AB, we observed a statistically significant difference (p <0.05) for MMP-2, MMP-7, EMMPRIN/CD147, Fibronectin, -smooth muscle actin, N-cadherin, Vimentin, Snail and Slug. Comparing \"epithelium vs stroma\" of CCOT, we observed a statistically significant difference (p <0.05) for MMP-9, RECK, EMMPRIN/CD147, Vimentin, N-cadherin, Snail and Slug. Analizing epithelium vs stroma\" between AB and CCOT, we observed a statistically significant difference (p <0.05) for MMP-2, MMP-7, MMP-9, RECK, EMMPRIN/CD147, Fibronectin, Vimentin , -smooth muscle actin, N-cadherin, Snail and Slug. This is the first time that EMMPRIN, RECK, TIMP-3, TIMP-4, N-cadherin, Snail and Slug are described in CCOT and TIMP-3, TIMP-4, Snail and Slug in AB. We conclude that these proteins/enzymes are differentially expressed in both epithelium and stroma of these tumors and suggest that they may participate locally invasive behavior.
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Influencing Pathways that Cause Metastasis and Stemness in Epithelial Ovarian CancerHuisken-Hill, Alyse Lynn 01 June 2016 (has links)
Ovarian cancer is the fifth leading cause of cancer death in women between the ages of 35 and 74. With 22 thousand new cases and 15 thousand deaths annually ovarian cancer is among the most deadly cancers with a death to incidence ratio of 68%. With 70% of cases High Grade Serous Ovarian Carcinoma (HGSOC) is the most common type of ovarian cancer and causes 90% of ovarian cancer deaths. 80% of patients have reoccurrence within five years and only 15-30% of patients with recurrent metastatic ovarian cancer respond to current therapies, chemotherapy and surgery. One reason for the high reoccurrence rate is thought to be linked to the heterogeneity of tumors: there is evidence that, among tumor cells, a subpopulation is cancer stem cells (CSCs). Since CSCs are frequently drug resistant, when the patient undergoes chemotherapy many of the cells may die but the CSCs are left behind and the tumors can therefore regrow. CSCs are also more likely to undergo epithelial-mesenchymal transition which gives these cells the ability to more readily migrate and invade through the extracellular matrix, leaving the primary tumor to form metastases. One key inducer of EMT and therefore possibly of metastasis of particular interest in this project is SNAI1 (Snail). It is therefore the goal of this project to understand the growth, makeup and metastatic ability of HGSOC cell lines to test possible strategies to decrease growth of cancer and prevent metastasis.
In this thesis project the phenotype, CSC population make up, and functionality of various HGSOC cell lines was examined. The cell lines assessed were A2780, Kuramochi, OVSAHO, COV318, SKOV3 and OVCAR8. A Snail knockdown OVCAR8 cell line was also assessed as described above and in a xenograft model. It was determined that the cell lines show varying phenotype from epithelial like to mesenchymal like morphology and the cell lines have varying concentrations of cancer stem cells. It was also determined that the CSC population of the HGSOC cell lines were positive for both epithelial and mesenchymal markers in the same cells. OVCAR8 stood out as a hybrid line with both epithelial and mesenchymal characteristics and was therefore chosen for the Snail knockdown model. In the Snail knockdown we observed that CSC markers were reduced, however no change between control and knockdown was seen in the in vitro functional experiments. There was a difference seen between Snail knockdown and control in the in vivo mouse xenograft model. Snail knockdown showed a trend for decreasing tumor burden in both primary and metastatic tumors and showed a significant decrease in growth of metastatic tumor at day 43. Based on these results Snail may be an important target for cancer therapy.
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Regulation der Nestinexpression bei der epithelial-mesenchymalen Transition / Regulation of nestin expression in the epithelial-mesenchymal transitionLotzkat, Anja Franziska 28 February 2012 (has links)
No description available.
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Rôle des eicosanoïdes post-greffe : implication dans la bronchiolite oblitérantePtaszynski, Stanislaw 02 1900 (has links)
Le rejet chronique se manifeste dans le poumon par la bronchiolite oblitérante
(BO), une pathologie inflammatoire et fibrotique menant à l’oblitération des
bronchioles. L’étiologie exacte de cette maladie demeure inconnue. Certaines études
suggèrent qu'un déséquilibre des leucotriènes (LT) sur les prostaglandines (PG)
favorise la fibrose pulmonaire. Les taux des LT et des PG dans le poumon humain
post-transplantation sont inconnus. Nous proposons qu'un déséquilibre de cystéinyl
leucotriènes (CysLT) sur la PGE2 existe dans le poumon transplanté et pourrait être
impliqué dans la pathogenèse de la BO. Aussi, les leucotriènes contribueraient à la
fibrose par la transition épithélio-mésenchymateuse (TEM). Afin de vérifier ces
hypothèses, nous avons déterminé les taux de CysLT et de PGE2 dans le liquide de
lavage broncho-alvéolaire (LBA) provenant de poumons transplantés chez l'homme
ainsi que leurs corrélations cliniques. Nous avons également déterminé la capacité
des CysLT à induire l’expression des marqueurs de la TEM in vitro. Nous avons
découvert des taux de CysLT et PGE2 supérieurs à la normale dans les LBA des
greffés. Un pic prédominant de CysLT sur PGE2 est observée à 52 semaines postgreffe
et deux facteurs de risque de la BO, les infections au CMV et à l’Aspergillus,
sont associés au ratio CysLT/PGE2> 1. In vitro, les CysLT induisent une répression
des marqueurs épithéliaux mais n’induisent pas l’expression de marqueurs
mésenchymateux chez les cellules épithéliales bronchiolaires. / Chronic rejection occurs, in the lung, in the form of bronchiolitis obliterans
(BO), an inflammatory and fibroproliferative disease that leads to the obliteration of
the bronchioles. A concept of the pathogenesis of BO has been suggested and several
risk factors are associated to it, however, the exact etiology of this disease remains
unknown. Studies have suggested that an imbalance of leukotrienes (LT) over
prostaglandins (PG) promotes pulmonary fibrosis. The levels of LT and PG in the
human lung post-transplantation are unknown. We propose that an imbalance of
cysteinyl leukotrienes (CysLT) on PGE2 exists in the transplanted lung and may be
implicated in the pathogenesis of BO. We also suggest that leukotrienes contribute to
fibrosis through epithelial-mesenchymal transition (EMT). In order to test these
hypotheses, we have determined the levels of CysLTs and PGE2 in human
transplanted lung bronchoalveolar lavage fluid (BALf) samples and their clinical
correlations. We have also determined the capacity of CysLT to induce the
expression of EMT markers in vitro. We found high average levels of CysLT and
PGE2 in the BAL of transplant patients. A predominant peak of CysLT over PGE2
was observed at 52 weeks post-transplantation and two risk factors for BO, CMV
infections and Aspergillus were associated with CysLT/PGE2 ratio> 1. According to
our experimental parameters, CysLT can induce the repression of epithelial markers
but do not induce the expression of mesenchymal markers in vitro in small airway
epithelial cells.
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