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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
241

Avaliação da recidiva do carcinoma hepatocelular em pacientes submetidos a transplante de fígado no Brasil / Recurrence of hepatocellular carcinoma assessment in patients submitted to liver transplantation in Brazil

Aline Lopes Chagas 01 December 2017 (has links)
INTRODUÇÃO: O transplante (TX) de fígado corresponde ao tratamento de escolha em pacientes com cirrose e carcinoma hepatocelular (CHC) precoce irressecável. A recidiva do CHC pós-transplante, entretanto, ainda apresenta impacto na sobrevida dos pacientes transplantados com este tumor. As taxas de recidiva, nos estudos mais recentes, variam de 8 a 20%. O tamanho e número de nódulos, a presença de invasão vascular e de nódulos satélites no explante, são fatores de risco relacionados à recidiva tumoral pós-transplante. No Brasil, observamos um crescimento importante do número de transplantes de fígado, inclusive por CHC. Entretanto, existem poucos estudos nacionais analisando os resultados do transplante hepático por CHC. Os objetivos do nosso estudo foram analisar as características demográficas, clínicas e a evolução dos pacientes submetidos a transplante hepático com CHC no Brasil, avaliando os fatores prognósticos relacionados com a recidiva do CHC pós-transplante e sobrevida e estudar o desempenho dos critérios de seleção para transplante utilizados no nosso país, os \"Critérios de Milão Brasil\" (CMB). MÉTODOS: Estudo de coorte retrospectivo, multicêntrico, para analisar os resultados do transplante de fígado em pacientes com CHC, após a implantação do sistema MELD. Foram incluídos 1.119 pacientes transplantados com CHC, de 07/2006 até 07/2015, em 13 centros de transplante, no Brasil. Características clínicas, demográficas, exames laboratoriais e de imagem e dados anatomopatológicos, foram retrospectivamente analisados e correlacionados com a sobrevida e recidiva do CHC pós-transplante. RESULTADOS: A maioria dos pacientes era do sexo masculino (81%), com uma idade média no TX de 58 anos. A etiologia mais associada ao tumor foi a Hepatite C (VHC), presente em 60% dos casos. O tempo médio de espera em lista foi de 9,8 meses. Setenta e oito pacientes (8%) foram incluídos por \"Down-staging\". Nos exames de imagem do diagnóstico, a maioria dos casos (67%) apresentava um nódulo, com tamanho médio de 30 mm; 85% estavam dentro dos Critérios de Milão (CM), 8% fora dos CM, mas dentro dos \"Critérios de Milão Brasil\" (CMB) e 7% fora de ambos os critérios. O tratamento do CHC em lista foi realizado em 67% dos pacientes. Na análise do explante, 44% apresentavam tumor uninodular, com tamanho médio de 26 mm e a maioria (71%) tinha CHC moderadamente diferenciado. A invasão vascular foi observada em 26% dos casos e nódulos satélites em 22%. No explante, 70% dos pacientes estavam dentro dos CM, 20,5% fora dos CM, mas dentro dos CMB e 9,5%fora de ambos os critérios. A sobrevida global foi de 79% em 1 ano, 72,5% em 3 anos e 63%, em 5 anos, com um tempo médio de seguimento de 28 meses. Excluindo os pacientes que foram a óbito no pós-operatório ( < 30 dias pós-transplante), a sobrevida global foi de 89% em 1 ano e 75%, em 5 anos. A recidiva do CHC pós-TX ocorreu em 8% (86/1.119) dos casos, em um tempo médio de 12 meses. A sobrevida livre de recidiva (SLR) foi de 94,4% em 1 ano e 88,3%, em 5 anos. A recidiva do CHC foi extra-hepática em 55% dos casos, hepática em 27% e hepática e extra-hepática em 18%. Os pacientes transplantados que evoluíram com recidiva tumoral apresentaram alta mortalidade, com uma sobrevida em 1 ano de 34% e em 5 anos de 13%. Em relação aos fatores prognósticos, os pacientes transplantados dentro dos Critérios de Milão apresentaram melhor sobrevida e SLR quando comparados aos pacientes transplantados fora dos CM, mas dentro dos CMB, tanto quando analisamos os dados do diagnóstico, quanto através da análise do explante. Os pacientes transplantados após realização de \"Down-staging\" apresentaram taxas de recidiva e sobrevida semelhantes aos pacientes transplantados sem \"Down-staging\". Os níveis séricos elevados de alfa-fetoproteína (AFP) foram um fator prognóstico importante de sobrevida e recidiva tumoral. Os melhores pontos de corte de AFP encontrados para avaliação do risco de recidiva e sobrevida foram: AFP > 400 ng/ml, no momento do diagnóstico e AFP > 200 ng/ml pré-transplante. Realizamos, também, uma comparação dos \"Critérios de Milão Brasil\" com os Critérios de Milão, através do índice IDI (Integrated Discrimination Index) e os CMB apresentaram performance inferior aos CM, na capacidade de classificar corretamente os pacientes em relação ao risco de recidiva tumoral. Os níveis séricos elevados de AFP, o estádio fora dos Critérios de Milão no momento do diagnóstico e no explante e a presença e invasão vascular no explante, foram fatores de risco independentes de recidiva do CHC pós-transplante e pior sobrevida. A idade > 60 anos e a etiologia da hepatopatia (VHC), também foram fatores prognósticos negativos de sobrevida. CONCLUSÕES: A presença de recidiva tumoral teve grande impacto na sobrevida do paciente transplantado com CHC. O estadiamento tumoral no diagnóstico e no explante, avaliado através dos Critérios de Milão, os níveis séricos elevados de AFP e a presença de invasão vascular no explante foram fatores prognósticos importantes de recidiva do CHC pós-transplante e sobrevida. Os pacientes transplantados após \"Down-staging\" apresentaram evolução pós-transplante semelhante a dos pacientes transplantados sem \"Down-staging\". Os pacientes transplantados fora dos CM, mas dentro dos CMB, apresentaram pior sobrevida, quando comparados aos pacientes dentro dos CM. Os CMB apresentaram desempenho inferior aos CM na capacidade de classificar corretamente os pacientes em relação ao risco de recidiva tumoral / INTRODUCTION: Liver transplantation (LT) is the treatment of choice for patients with cirrhosis and unresectable early hepatocellular carcinoma (HCC). HCC post-transplant recurrence, however, still has an impact on survival. In recent studies, the incidence of HCC recurrence after transplantation ranged from 8% to 20%. Tumor number, size, vascular invasion and satellite nodules have emerged as risk factors for HCC recurrence. In Brazil, in the last decade, we observed a significant increase in the number of liver transplants performed, including in patients with HCC. However, there are few national studies analyzing the results of liver transplantation for HCC. The aim of this multicentric study was to analyze the demographic characteristics, clinical features and outcomes of patients submitted to liver transplantation with HCC in Brazil, evaluate prognostic factors related to HCC post-transplant recurrence and survival, and study the performance of the national selection criteria for liver transplantation, the \"Brazilian Milan Criteria\" (BMC). METHODS: We conducted a national, multicentric, retrospective study to analyze the results of liver transplantation in patients with HCC, in \"MELD era\". Medical records of 1,119 transplanted patients with HCC between 07/2006 and 07/2015, from 13 transplant centers in Brazil, were collected. Patient and tumor characteristics, radiologic and pathologic data were retrospectively analyzed and correlated with post-transplant HCC recurrence and survival. RESULTS: Of the 1,119 HCC transplanted patients, median age was 57 years and 81% were male. Etiology of liver disease was HCV in 60%. Median time on transplant list was 9.8 months. Seventy-eight patients (8%) were included after \"Down-staging\". At diagnosis, most patients had uninodular HCC (67%) and median tumor burden was 30 mm. At diagnosis, in imaging studies, 85% of patients were within the Milan criteria (MC), 8% out of the MC but within the \"Brazilian Milan Criteria\" (BMC) and 6% out of both criteria. During the waiting list period, HCC treatment was performed in 67%. In explant analysis, tumor was uninodular in 46% and moderately differentiated in the majority of cases (71%). Median HCC size was 26 mm. Vascular invasion and satellite nodules were observed in 26% and 22% of patients, respectively. In explant, 70% of patients were within Milan Criteria, 20.5% outside MC but within BMC and 9.5% out of both criteria. Mean follow-up was 28 months, an overall survival was 79% in 1 year, 72.5% in 3 years and 63% in 5 years. Excluding patients who died within 30 days after surgery, overall survival was 89% in 1 year and 75% in 5 years. HCC post-transplant recurrence occurred in 86/1,119 (8%) cases, at a mean time of 12 months. Recurrence-free survival (RFS) was 94.4% in 1 year and 88.3% in 5 years. Sites of recurrence were extrahepatic in 55%, hepatic in 27% and both hepatic and extrahepatic in 18%. Transplanted patients with tumor recurrence presented high mortality, with 1-year survival rate of 34% and 5-year survival rate of 13%. Analyzing the prognostic factors, patients transplanted under Milan Criteria, in radiologic or explant analysis, presented better survival and RFS when compared to patients transplanted outside MC, but within BMC. Patients submitted to liver transplantation after \"Down-staging\" present long-term survival and RFS similar to patients transplanted without \"Down-staging\". Alpha-fetoprotein (AFP) levels were an important pre-transplant prognostic factor for tumor survival and recurrence. The best AFP cut off points found for relapse risk and survival assessment were: AFP at diagnosis > 400 ng / ml and AFP pre-transplant > 200 ng / ml. We also performed a comparison of the \"Brazilian Milan Criteria\" with the Milan Criteria through the Integrated Discrimination Index (IDI). The BMC presented a lower performance than the MC, in the ability to correctly classify patients in relation to the risk of relapse. Elevated AFP levels before liver transplantation, tumor outside Milan Criteria at diagnosis and in explant, and vascular invasion, were independent risk factors for post-transplant HCC recurrence and worse survival. Age > 60 years and etiology of liver disease (HCV), were also negative prognostic factors for survival. CONCLUSIONS: The presence of tumor recurrence had a major impact on survival of transplanted patients with HCC. Tumor staging, evaluated by Milan Criteria on imaging studies or explant analysis, high serum AFP levels and presence of vascular invasion in explant were important prognostic factors for post-transplant HCC recurrence and survival. Patients transplanted after Down-staging presented long-term outcomes similar to patients transplanted under conventional criteria. Patients transplanted outside Milan Criteria, but within \"Brazilian Milan Criteria\" presented worse survival, when compared to patients within MC. The BMC showed lower performance than MC in the ability to correctly classify patients in relation to the risk of tumor recurrence
242

Elastografia hepática em pacientes com carcinoma hepatocelular em triagem para transplante de fígado / Liver elastography in patients with hepatocellular carcinoma in screening for liver transplantation

Lucas Souto Nacif 15 December 2014 (has links)
INTRODUÇÃO: A cirrose é a oitava causa de mortalidade no mundo, e sua progressão e estadiamento são de extrema importância nos pacientes com doença terminal do fígado. A presença de cirrose é reconhecida como risco aumentado de carcinoma hepatocelular (CHC) e o seu aparecimento está diretamente relacionado ao grau de fibrose do fígado. Na última década, notou-se o desenvolvimento e aperfeiçoamento dos métodos de predição do grau de fibrose e cirrose, através de métodos não-invasivos, com o objetivo de substituir a biópsia hepática. A população em lista de espera para transplante de fígado apresenta graus diferentes de fibrose hepática, que pode não estar diretamente relacionada ao MELD. Além disso, esses pacientes apresentam CHC no momento da triagem para transplante de fígado. Não existe avaliação desta população por elastografia. OBJETIVO: O objetivo deste trabalho foi avaliar os pacientes em triagem para transplante de fígado, com e sem carcinoma hepatocelular, pela elastografia hepática com Fibroscan® e ARFI. MÉTODO: Foram estudados 103 pacientes adultos do ambulatório de triagem da Disciplina de Transplante de Órgãos do Aparelho Digestivo HC/FMUSP, no período de outubro de 2012 à dezembro de 2013. A amostragem foi por conveniência e foram avaliados dados clínicos, epidemiográficos, laboratoriais, imagem, elastográficos e o desfecho. Análise de elastografia transitória (ET) foi feita pelo Fibroscan® TM (Echosens, França) e força impulso por radiação acústica (ARFI) (Siemens Acuson S2000, Alemanha) nos grupos com e sem CHC comprovados de acordo com orientação de diagnóstico pelas diretrizes européias (EASL) e americanas (AASLD). Para a análise estatística foi realizado o teste de Mann-Whitney, teste não paramétrico aplicado para duas amostras independentes; o teste de Fisher e o método ANOVA através do teste de Kruskal-Wallis ou teste de Tukey para comparações múltiplas. Foi realizado também a curva ROC para avaliação dos testes diagnósticos e ponto de corte. O valor considerado de p significativo foi <0,05. RESULTADOS: Entre os pacientes avaliados, a maioria foi de homens (68%), com idade média de 53 ± 11,5 anos. A etiologia mais comum foi o vírus da hepatite C (VHC) em 34,9%. A classificação pelo escore Child-Turcotte-Pugh (CTP) mostrou: pacientes classe A em 38,4%, classe B em 47,2% e classe C em 14,2%. O valor do MELD médio dos pacientes foi de 14,75 (± 6,45) e a mediana de 14 (variando, 6 - 32). Na população estudada de 103 pacientes, a ET (Fibroscan®) foi realizada com sucesso em 75 de 103 pacientes e ARFI em 78 de 78 pacientes. A etiologia VHC e elevados valores de alfa-feto proteína foram fatores de risco para a presença de CHC. Os valores de MELD mais elevados foram significativos nos pacientes que evoluíram a óbito. A curva ROC mostrou respectivamente sensibilidade e especificidade para a AFP de 50% e 86% (valor de corte 9,1); ET (valor de corte 9 kPa) 92% e 17%; e ARFI 21% e 92% (valor de corte 2,56 m/s). O valor médio da ET nos pacientes com CHC foi de 30,4 ± 21,0 kPa, do ARFI do parênquima hepático foi de 1,97 ± 0,64 e ARFI do nódulo hepático foi de 1,89 ± 0,74. CONCLUSÃO: Os pacientes em triagem para transplante de fígado com carcinoma hepatocelular apresentam valores elevados de elastografia tanto pelo Fibroscan® quanto pelo ARFI®. A elastografia apresenta-se como uma importante ferramenta não invasiva para o acompanhamento de cirróticos graves podendo ajudar no manejo do carcinoma hepatocelular / INTRODUCTION: Cirrhosis is the eighth leading cause of mortality worldwide and its progression and staging are extremely important in patients with end liver disease. The presence of cirrhosis is recognized as an increased risk of hepatocellular carcinoma (HCC) and its incidence is directly related to the degree of liver fibrosis. In the last decade, was noted the development and improvement of methods for predicting the degree of fibrosis and cirrhosis using non-invasive methods, aiming to replace the liver biopsy. The population on the liver transplant waiting list presents different degrees of liver fibrosis, which may not be directly related to MELD. In addition, these patients have HCC at the time of screening for liver transplantation. There is no evaluation of this population by elastography. OBJECTIVE: The aim of this study was to evaluate patients on screened to the list for liver transplantation, with and without hepatocellular carcinoma, by liver elastography with Fibroscan and ARFI. METHOD: Were studied 103 adult patients from the screening for liver transplantation waiting list on the Liver and Gastrointestinal Transplant Division HC/FMUSP from October 2012 to December 2013. Sampling for convenience and evaluation clinical data, epidemiological, laboratory, imaging, elastography findings and outcome. Analysis of transient elastography (TE) by Fibroscan TM (Echosens, France) and Acoustic Radiation Force Impulse (ARFI) by (Siemens Acuson S2000, Germany) in patients with and without HCC proven in accordance with guidelines of diagnosis EASL/AASLD. Fisher\'s ANOVA or Kruskal-Wallis tests Whitney-Mann Test were performed. Tukey and define cut-of for examinations with ROC curves. The p value considered was < 0.05. RESULTS: Among the patients, the majority were men (68%), mean age 53 ± 11.5 years. This is the most common cause of hepatitis C virus (HCV) 34.9%. The classification by Child-Turcotte-Pugh score (CTP) showed: class A patients in 38.4%, 47.2% in class B and class C in 14.2%. The average value of MELD patients was 14.75 (± 6.45) and a median of 14 (range, 6-32). In the study population of 103 patients, the ET (Fibroscan) was successfully performed in 75 of 103 patients and ARFI in 78 of 78 patients. The HCV etiology and high levels of alpha-fetoprotein were risk factors for the presence of HCC. MELD values were significant higher in patients who died. The ROC curve shown respectively sensitivity and specificity for AFP of 50% and 86% (cutoff 9.1); ET (9 cutoff kPa) 92% to 17%; and ARFI 21% and 92% (cut-off 2.56 m / s). The average value of ET in HCC patients was 30.4 ± 21.0 kPa, the ARFI parenchymal liver was 1.97 ± 0.64 and ARFI liver nodules was 1.89 ± 0.74. CONCLUSION: Patients in screening for liver transplantation with hepatocellular carcinoma have elevated values of both elastography by Fibroscan as the ARFI®. Elastography is presented as an important non-invasive tool for monitoring severe cirrhosis may help in management of hepatocellular carcinoma
243

Caracterização das mutações da região core do vírus da hepatite C associadas ao carcinoma hepatocelular / Characterization of mutations in Hepatitis C virus core region associated with hepatocellular carcinoma

João Paulo Moreira 01 December 2015 (has links)
A infecção pelo vírus da hepatite C (HCV) pode evoluir gradualmente para hepatite crônica, cirrose e carcinoma hepatocelular (CHC) ao longo de 20 a 30 anos [1-3]. O carcinoma hepatocelular é a quinta neoplasia mais comum em todo o mundo, sendo responsável por mais de 600.000 mortes por ano. Atualmente, cerca de 170 milhões de indivíduos estão infectados pelo HCV, o que corresponde a aproximadamente 3% da população do mundo. A hepatocarcinogênese é um processo complexo, com várias etapas que envolvem alterações genéticas e epigenéticas. Estudos relatam que substituições de aminoácidos (aa) na posição 70 e 91 da região core do HCV podem estar relacionados ao desenvolvimento de CHC. O conhecimento sobre os mecanismos da carcinogênese que envolvem o HCV são importantes para a descoberta de biomarcadores e potenciais alvos terapêuticos do CHC. Neste estudo, foram analisados os genótipos virais e a presença de mutações na região core do HCV, em 94 pacientes com CHC e em 79 pacientes cirróticos (sem CHC). As sequências da região core do HCV foram obtidas pelo método de sequenciamento populacional baseado na metodologia de Sanger. Características demográficas, bioquímicas e sorológicas também foram avaliadas. A idade dos pacientes com CHC foi significativamente maior do que a dos pacientes sem CHC (63 vs 60,5 anos, P=0,025). Uma proporção maior de homens foi observada no grupo CHC (64,4% vs 54%, P=0,329), qual apresentou nível de alfafetoproteína significativamente mais elevado (P=0,003) e menores níveis de albumina em relação ao grupo sem CHC (P=0,012). Elevada variabilidade genética do HCV foi observada. Ao todo, quatro genótipos e sete subtipos foram encontrados. O subtipo 1 b foi o mais frequente em ambos os grupos. Os subtipos encontrados no grupo CHC e cirróticos foram, 1a (13,6%), 1 b (45,7%), 3a (28,8%), 2b (6,8%), 2a (1,7%), 2c (1,7%), 5a (1,7%); e 1a (30%), 1 b (44%), 3a (22%), 2b (2%) e 5a (2%). As mutações R70Q e UC91 M foram observadas principalmente no HCV genótipo 1 b. Não houve associação entre mutações nas posições 70 e 91 na região core do HCV e o desenvolvimento de CHC / Hepatitis C virus (HCV) infection is often persistent and gradually advances from chronic hepatitis (CH) to liver cirrhosis, and hepatocellular carcinoma (HCC) over 20 to 30 years [1-3]. Worldwide, hepatocellular carcinoma is the fifth most common neoplasm and is responsible for more than 600,000 deaths annually due to very poor prognosis. There are about 170 million individuais infected with HCV, corresponding to approximately 3% of world population. Hepatocarcinogenesis is a complex process involving genetic and epigenetic modifications. Studies have reported that amino acid substitutions (a a) at position 70 and 91 of HCV core region may be related to development of HCC. Understanding the pathogenesis of HCV-induced hepatocarcinogenesis is important to identify novel biomarkers and potential therapeutic targets. In this study, the viral genotypes and the presence of mutations in HCV core region were analyzed in 94 patients with HCC, and also in 79 cirrhotic patients (without HCC). HCV core sequences were obtained using population sequencing based on Sanger method. Demographic, biochemical and serological characteristics were also evaluated. The age of patients with HCC were significantly higher than in patients without HCC (63 vs. 60.5 years, P=0.025). High proportion of men was observed in HCC group (64.4% vs 54%, P=0.329). Alpha-fetoprotein levei was significantly higher in HCC group compared to cirrhotic group (P=0.003), and low rates of albumin was observed in cirrhotic group (P=0.012). High genetic variability of HCV was observed, in HCC group, however genotype 1 b was the most common in both groups. Other genotypes were found in HCC group: 1a (13.6%), 1 b (45.7%), 3a (28.8%) 2b (6.8%), 2a (1.7%), 2c (1.7%) and 5a (1.7%). In cirrhotic group was found genotypes 1 a (30%), 1 b (44%), 3a (22%), 2b (2%) and 5a (2%). Mutations R70Q and LlC91 M were mainly observed in individuais infected with HCV genotype 1 b. In the present study, no association between mutations at positions 70 and 91 of HCV
244

Análise da expressão de EGFR e de proteínas relacionadas em carcinoma hepatocelular, tecido hepático circunjacente e metástase: estudo clínico-patológico em autópsias / Analysis of the expression of EGFR and related proteins in hepatocellular carcinoma, surrounding liver tissue and metastases : a clinicopathological study in autopsies

Aloísio Souza Felipe da Silva 04 June 2013 (has links)
OBJETIVOS: Analisar a expressão de EGFR, proteínas da via de sinalização ou relacionadas aos seus efeitos em carcinoma hepatocelular (CHC) primários, metastáticos e em tecido hepático não tumoral em autópsias. Correlacionar os achados a dados clínico-patológicos e marcadores de classes moleculares. Avaliar a heterogeneidade de expressão em CHC metastáticos e fatores de disseminação extra-hepática. MÉTODOS: Oitenta autópsias de pacientes com CHC ao exame foram incluídas em estudo retrospectivo transversal. Foram analisados sexo, idade, raça, etilismo, infecção por vírus da hepatite B (VHB) e C (VHC), infecção pelo HIV, tratamento prévio, causas básica e imediata de óbito, peso do fígado, cirrose, número e tamanho dos nódulos, padrão macroscópico, grau histológico, variantes histológicas, padrão arquitetural, invasão de grandes veias e metástases extra-hepáticas. Imuno-histoquímica foi realizada em micromatrizes teciduais para pesquisa de EGFR, pEGFR(Tyr 1173), HER2, ERK1/2, MAPKAPK-2, pMAPK, Ag Ki67, caspase 3, citoqueratina 19 (CK19), mTOR, ciclina D1, Met, vimentina, p53 e beta-catenina. A expressão de EGFR foi avaliada em intensidade (0-3+) e distribuição (0-100%) em um sistema de escores de 0 a 300. Hiperexpressão foi definida para escores >= 200. Amostras de fígado normal foram incluídas como controles. Amostras de CHC primário foram pareadas às suas metástases e consideradas concordantes quando na mesma categoria de expressão. No tecido não tumoral foram semi-quantificadas a reação ductular expressando CK19 e a densidade da população de células estromais perissinusoidais pela vimentina. Estatística foi realizada através dos testes do qui-quadrado ou exato de Fisher ao nível de significância de 0,05. Para as correlações de escores e variáveis categóricas foi utilizado o coeficiente de Spearman. RESULTADOS: Foram incluídos 62 casos do sexo masculino e 18 do sexo feminino (58,1 ± 10,9 anos). Infecção pelo VHC foi a principal causa em 49% (39/80), seguida por etilismo em 30% (24/80) e infecção por VHB em 19% (15/80). Cirrose foi identificada em 90% (72/80) dos casos. Os tumores mostraram-se avançados em 95% (76/80). Invasão de grandes veias foi detectada em 19% (15/80) e metástases extra-hepáticas em 38% (30/80). MAPKAPK2, pEGFR (Tyr1173) e HER2 tiveram expressão fraca ou ausente. A expressão de EGFR foi mais frequente no fígado não neoplásico (26/26) (P < 0,05) - e nos controles normais (8/8) do que nas amostras tumorais primárias (60/75) e nas metástases (12/17). Nenhuma amostra dos controles apresentou hiperexpressão de EGFR, a qual foi mais frequente na cirrose (65% - 17/26) do que nos tumores avançados (36% - 26/72) (P < 0,05). EGFR hiperexpresso foi mais frequente nos tumores de grau 1/2 (P < 0,01) e nos casos com menos de quatro nódulos hepáticos (P = 0,014). A expressão de EGFR correlacionou-se à expressão de caspase 3 (P < 0,01). A expressão das quinases ERK1 e ERK2 foi correlacionada à proliferação celular pelo Ag Ki67 (P < 0,01), porém não ao escore de expressão de EGFR. CK19, p53 e beta-catenina nuclear foram correlacionaram-se às lesões de maior grau e a maiores taxas de proliferação celular (P<0,01). Met, EGFR e caspase 3 foram correlacionados a lesões mais diferenciadas. Vimentina teve forte correlação com CK19 (P < 0,01). A concordância de expressão entre tumores hepáticos e respectivas metástases variou de 50 a 85%. Para o EGFR foi de 61%. A expressão endotelial 2-3+ de pMAPK foi mais frequente nas metástases (P = 0,09). A disseminação extra-hepática foi mais frequente nos casos com baixa densidade de células perissinusoidais positivas para vimentina (P = 0,054) e nos casos sem reação ductular no tecido não neoplásico (P = 0,095). CONCLUSÕES: O EGFR tem papel relevante nas etapas iniciais e intermediárias do CHC, sendo sua expressão reduzida nas formas avançadas. Diferentes classes de CHC podem estar associadas a ativação da via do EGFR. A presente análise imuno-histoquímica ampla parece validar pelo menos dois grupos de CHC que nesta série de autópsias parecem ter sido separados pelo grau histológico. Confirma-se a hiperexpressão das quinases como evento importante na progressão tumoral, porém não necessariamente associada à hiperexpressão de EGFR. A heterogeneidade de expressão entre o CHC primário e suas metástases variou de 15 a 45% / OBJECTIVES: To analyze the expression of EGFR and proteins related to its signaling pathway or to its effects in hepatocellular carcinoma (HCC), metastases and surrounding liver tissue in a series of autopsies. To correlate expression patterns to clinicopathological data and other markers of molecular classification. To assess the heterogeneity of expression in metastatic HCC and factors related to extrahepatic spread. METHODS: Eighty autopsies of patients with HCC were included in a cross-sectional retrospective study. We analyzed gender, age, race, alcohol intake, infection with hepatitis B (HBV) and C virus (HCV), HIV infection, prior treatment, basic and immediate causes of death, the weight of the liver, cirrhosis, number and size of nodules, gross pattern, histological grade, histological variants, architectural pattern, invasion of large veins and extrahepatic metastases. Immunohistochemistry was performed on tissue microarrays to survey EGFR, pEGFR(Tyr 1173), HER2, ERK1/2, MAPKAPK-2, pMAPK, Ag Ki67, caspase 3, cytokeratin 19 (CK19), mTOR, cyclin D1, Met, vimentin, p53 and beta-catenin. EGFR expression was evaluated in intensity (0-3+) and distribution of membrane staining (0-100%) in a 0 - 300 score. Overexpression was defined for scores >= 200. Normal liver samples were included as controls. Intra-hepatic HCC samples were matched to their respective metastases and expression was considered concordant when they were assigned to the same category. Ductular reaction expressing CK19 and the density of perisinusoidal vimentin positive stromal cells were semi-quantified in non-tumor tissue. Statistics was performed using the chi- square or Fisher exact test at a significance level of 0.05. For the correlations of scores and categorical data we used the Spearman coefficient. RESULTS: Sixty-two males and eighteen females were included (age 58.1 ± 10.9). HCV was the major cause in 49% (39/80), followed by alcoholism in 30% (24/80) and HBV infection in 19% (15/80). Cirrhosis was identified in 90% (72/80) and advanced tumors in 95% (76/80). Large vein invasion was detected in 19% (15/80) and extra-hepatic metastases in 38% (30/80). MAPKAPK2, pEGFR (Tyr1173) and HER2 expression were weak or absent. The EGFR expression was more frequent in non-tumoral liver (26/26) (P <.05) and in normal controls (8/8) than in primary HCC tumor samples (60/75) and in metastatic HCC (12/17). No samples taken from the controls showed overexpression of EGFR, which was more common in cirrhotic tissue (65% - 17/26) than in advanced tumors (36% - 26/72) (P <0.05). EGFR overexpression was more frequent in grade 1/2 tumors (P <0.01) and in cases with less than four hepatic nodules (P = 0.014). EGFR expression was correlated to the expression of caspase 3 (P <0.01). The expression of the kinases ERK1 and ERK2 was correlated to Ag Ki67 cell proliferation index (P <0.01), but not to the EGFR expression score. CK19, p53 and nuclear beta- catenin were correlated to high grade lesions and to higher rates of cell proliferation (P <0.01). Met, EGFR and caspase 3 were correlated with more differentiated lesions. Vimentin was strongly correlated with CK19 (P <0.01). The concordance of expression between liver tumors and their metastases ranged from 50 to 85% (61% for EGFR). The 2-3+ expression of pMAPK in tumor endothelial cells was more common in metastases (P = 0.09). Extrahepatic dissemination was more frequent in cases with low density of vimentin positive perisinusoidal cells (P = 0.054) and in cases with no detectable ductular reaction in non-neoplastic tissue (P = 0.095). CONCLUSIONS: EGFR plays an important role in the early and intermediate stages of HCC progression, with lower expression in advanced tumors. Different classes of HCC may be associated with activation of EGFR. The present comprehensive immunohistochemical approach seems to validate at least two molecular classes of HCC, and histological grade seems to be able to discriminate these groups. We herein confirmed overexpression of kinases as a key event in tumor progression, but not necessarily associated with overexpression of EGFR. The heterogeneity of expression between primary HCC and its metastases ranged from 15 to 45%
245

The pathological and genomic impact of CTCF depletion in mammalian model systems

Aitken, Sarah Jane January 2018 (has links)
CCCTC-binding factor (CTCF) binds DNA, thereby helping to partition the mammalian genome into discrete structural and regulatory domains. In doing so, it insulates chromatin and fine-tunes gene activation, repression, and silencing. Complete removal of CTCF from mammalian cells causes catastrophic genomic dysregulation, most likely due to widespread collapse of 3D chromatin looping within the nucleus. In contrast, Ctcf hemizygous mice with lifelong reduction in CTCF expression are viable but have an increased incidence of spontaneous multi-lineage malignancies. In addition, CTCF is mutated in many human cancers and is thus implicated as a tumour suppressor gene. This study aimed to interrogate the genome-wide consequences of a reduced genomic concentration of Ctcf and its implications for carcinogenesis. In a genetically engineered mouse model, Ctcf hemizygous cells showed modest but robust changes in almost a thousand sites of genomic CTCF occupancy; these were enriched for lower affinity binding events with weaker evolutionary conservation across the mouse lineage. Furthermore, several hundred genes concentrated in cancer-related pathways were dysregulated due to changes in transcriptional regulation. Global chromatin structure was preserved but some loop interactions were destabilised, often around differentially expressed genes and their enhancers. Importantly, these transcriptional alterations were also seen in human cancers. These findings were then examined in a hepatocyte-specific mouse model of Ctcf hemizygosity with diethylnitrosamine-induced liver tumours. Ctcf hemizygous mice had a subtle liver-specific phenotype, although the overall tumour burden in Ctcf hemizygous and wild-type mice was the same. Using whole genome sequencing, the highly reproducible mutational signature caused by DEN exposure was characterised, revealing that Braf(V637E), orthologous to BRAF(V600E) in humans, was the predominant oncogenic driver in these liver tumours. Taken together, while Ctcf loss is partially physiologically compensated, chronic CTCF depletion dysregulates gene expression by subtly altering transcriptional regulation. This study also represents the first comprehensive genome-wide and histopathological characterisation of this commonly used liver cancer model.
246

MicroRNA profiling of human hepatocytes induced by HBx in hepatocarcinogenesis.

January 2009 (has links)
Yip, Wing Kit. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2009. / Includes bibliographical references (leaves 100-119). / Abstract also in Chinese. / Abstract (English version) --- p.i / Abstract (Chinese version) --- p.iii / Acknowledgments --- p.v / Table of Contents --- p.vii / List of Tables --- p.x / List of Figures --- p.xi / List of Abbreviations --- p.xiii / Chapter CHAPTER 1 --- INTRODUCTION --- p.1 / Chapter 1.1 --- Hepatocellular Carcinoma --- p.1 / Chapter 1.1.1 --- Epidermiology --- p.1 / Chapter 1.1.2 --- Etiology --- p.1 / Chapter 1.2 --- Hepatitis B Virus --- p.3 / Chapter 1.2.1 --- The Epidermiology of Hepatitis B Virus Infection --- p.3 / Chapter 1.2.2 --- The Morphology and Genome of Hepatitis B Virus --- p.4 / Chapter 1.2.3 --- HBV Genotypes and Their Significance --- p.8 / Chapter 1.3 --- Hepatitis B Virus X Protein --- p.9 / Chapter 1.3.1 --- HBx Alters Various Signal Transduction Pathways --- p.10 / Chapter 1.3.2 --- HBx Interacts with Various Transcription Factors and Co-activators --- p.12 / Chapter 1.3.3 --- HBx Induces Epigenetic Alterations --- p.14 / Chapter 1.3.4 --- Identification of COOH-terminal Truncated HBx in Liver Tumors --- p.15 / Chapter 1.4 --- MicroRNAs --- p.17 / Chapter 1.4.1 --- Transcriptional Regulation and Biogenesis of MicroRNAs --- p.18 / Chapter 1.4.2 --- MicroRNAs and Cancer --- p.21 / Chapter 1.4.3 --- MicroRNAs and HCC --- p.25 / Chapter 1.5 --- Hypothesis and Aims of the Study --- p.29 / Chapter CHAPTER 2 --- MATERIALS and METHODS --- p.30 / Chapter 2.1 --- Patients --- p.30 / Chapter 2.2 --- Cell Lines --- p.30 / Chapter 2.3 --- Cloning of Various HBx Constructs --- p.32 / Chapter 2.3.1 --- PCR Amplification of HBx Fragments --- p.32 / Chapter 2.3.2 --- Cloning of HBx Fragments into TA-vectos --- p.33 / Chapter 2.3.3 --- Heat Shock Transformation --- p.33 / Chapter 2.3.4 --- Sub-cloning of HBx Fragments into Lentiviral Vectors --- p.34 / Chapter 2.4 --- Generation of Lentivirus --- p.37 / Chapter 2.4.1 --- Lentivirus Infection --- p.37 / Chapter 2.5 --- RNA Extraction --- p.38 / Chapter 2.6 --- Western Blot Analysis --- p.39 / Chapter 2.7 --- MiRNA Microarray --- p.40 / Chapter 2.7.1 --- Cyanine3-pCp Labeling of RNA Samples --- p.40 / Chapter 2.7.2 --- Sample Hybridization --- p.41 / Chapter 2.7.3 --- Microarray Wash --- p.41 / Chapter 2.7.4 --- Array Slide Scanning and Processing --- p.41 / Chapter 2.8 --- Detection of HBx Gene Deletion by PCR --- p.43 / Chapter 2.9 --- Immunohistochemistry --- p.44 / Chapter 2.10 --- Quantitative Real-time PCR --- p.45 / Chapter 2.11 --- Proliferation Assay --- p.47 / Chapter 2.12 --- Cell Cycle Analysis --- p.48 / Chapter 2.13 --- Annexin V Apoptosis Assay --- p.49 / Chapter 2.14 --- Colony Formation Assay --- p.50 / Chapter 2.15 --- Statistical Analysis --- p.51 / Chapter CHAPTER 3 --- RESULTS --- p.52 / Chapter 3.1 --- Detection of Full-length and COOH-terminal Truncated HBx in HCC Tissues --- p.52 / Chapter 3.2 --- Confirmation of HBx Expression in HCC Tissues --- p.55 / Chapter 3.3 --- Comparison of HBx from Different HBV Genotypes for Study --- p.61 / Chapter 3.4 --- Functional Characterization of COOH-tterminal Truncated HBx --- p.64 / Chapter 3.4.1 --- Selection of COOH-terminal Truncated HBx --- p.64 / Chapter 3.4.2 --- Generation of Various HBx-expressing Hepatocyte Cell Lines --- p.66 / Chapter 3.4.3 --- Effect of Full-length and COOH-terminal Truncated HBx on Cell Proliferation --- p.69 / Chapter 3.4.4 --- Effect of Full-length and COOH-terminal Truncated HBx Cell Cycle --- p.34 / Chapter 3.4.5 --- Effect of Full-length and COOH-terminal Truncated HBx on Apoptosis --- p.45 / Chapter 3.5 --- MicroRNA Profiling of Various HBx-expressing Hepatocyte Cell Lines --- p.76 / Chapter 3.5.1 --- Identification of Deregulated MicroRNAs by Microarray --- p.76 / Chapter 3.5.2 --- Validation of Deregulated MicroRNAs by Real-time PCR Analysis --- p.80 / Chapter 3.5.3 --- Confirmation of Deregulated MiRNAs in HCC and Adjacent Non-tumor Tissues --- p.84 / Chapter 3.5.4 --- Potential Downstream Targets of the HBx-deregulated MiRNAs --- p.87 / Chapter CHAPTER 4 --- DISCUSSION --- p.91 / Chapter 4.1 --- The Impact of COOH-terminal Truncated HBx in HCC --- p.91 / Chapter 4.2 --- The Biological Significance of COOH-terminal Truncated HBx Induced MiRNAs --- p.94 / Chapter 4.3 --- Limitations of the Present Study --- p.97 / Chapter 4.4 --- Future Studies --- p.98 / Chapter CHAPTER 5 --- CONCLUSION --- p.99 / REFERENCES --- p.100
247

Determination of the differential roles of wild-type and C-terminal truncated hepatitis B virus X protein in hepatocarcinogenesis and construction of inducible cells expressing truncated HBx.

January 2007 (has links)
Li, Sai Kam. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2007. / Includes bibliographical references (leaves 162-179). / Abstracts in English and Chinese. / Abstract --- p.i / Abstract in Chinese (摘要) --- p.ii / Acknowledgements --- p.iii / Table of Content --- p.iv / Abbreviations --- p.xi / List of Figures --- p.xiv / List of Tables --- p.xvii / Chapter CHAPTER 1 --- INTRODUCTION / Chapter 1.1 --- Hepatitis B Virus / Chapter 1.1.1 --- General information --- p.1 / Chapter 1.1.2 --- Classification --- p.2 / Chapter 1.1.3 --- Virus life cycle and genome --- p.3 / Chapter 1.1.4 --- Hepatitis B virus X protein (HBx) --- p.7 / Chapter 1.2 --- Enigmatic functions of HB --- p.x / Chapter 1.2.1 --- HBx as a transactivator --- p.10 / Chapter 1.2.2 --- HBx as a cell cycle regulator --- p.12 / Chapter 1.2.3 --- HBx as an apoptosis modulator --- p.13 / Chapter 1.3 --- Etiology of HBV-mediated hepatocarcinogenesis --- p.14 / Chapter 1.4 --- Clinical mutants of HBV --- p.16 / Chapter 1.5 --- Hypothesis and aims of the research --- p.16 / Chapter 1.6 --- Basis of Tet-On system --- p.18 / Chapter CHPATER 2 --- EXPERIMENT MATERIALS / Chapter 2.1 --- Cell culture / Chapter 2.1.1 --- Cell-lines --- p.21 / Chapter 2.1.2 --- Culture medium --- p.22 / Chapter 2.1.3 --- Culture medium supplements --- p.23 / Chapter 2.2 --- Reagents for subcloning / Chapter 2.2.1 --- Reagents for polymerase chain reaction (PCR) --- p.24 / Chapter 2.2.2 --- Reagents for restriction enzyme digestion --- p.24 / Chapter 2.2.3 --- Reagents for ligation --- p.25 / Chapter 2.2.4 --- Reagents for electrophoresis --- p.25 / Chapter 2.2.5 --- Reagents for E. coli DH5a preparation --- p.25 / Chapter 2.2.6 --- Materials for bacterial culture work --- p.27 / Chapter 2.3 --- Reagents for subcellular localization study / Chapter 2.3.1 --- Reagents for cell staining --- p.28 / Chapter 2.3.2 --- Reagents for mounting slides --- p.29 / Chapter 2.3.3 --- Materials for site-directed mutagenesis --- p.29 / Chapter 2.4 --- Reagents for cell cycle analysis and cellular proliferation / Chapter 2.4.1 --- Reagents for cell cycle analysis --- p.29 / Chapter 2.4.2 --- Reagents for cellular proliferation study --- p.30 / Chapter 2.5 --- Reagents for protein expression study / Chapter 2.5.1 --- Cell lysis buffer --- p.30 / Chapter 2.5.2 --- Reagents for SDS-PAGE --- p.30 / Chapter 2.5.3 --- Reagents for Western blot --- p.33 / Chapter 2.5.4 --- Antibodies --- p.34 / Chapter 2.6 --- Reagents for gene expression study / Chapter 2.6.1 --- Reagents for RNA extraction --- p.36 / Chapter 2.6.2 --- Reagents for first strand cDNA synthesis --- p.37 / Chapter 2.6.3 --- Reagents for real-time PCR --- p.37 / Chapter 2.7 --- Reagents for establishment of Tet-On inducible stable cell-lines / Chapter 2.7.1 --- Reagents for MTT assay --- p.38 / Chapter 2.7.2 --- Reagents for selection of stable clones --- p.38 / Chapter 2.8 --- Vectors used in the project / Chapter 2.8.1 --- Vectors for subcellular localization study --- p.39 / Chapter 2.8.2 --- Vectors for establishment of Tet-on inducible cell-lines --- p.39 / Chapter 2.9 --- Primers used in the project / Chapter 2.9.1 --- Primers used for subcloning --- p.42 / Chapter 2.9.2 --- Primers used for site-directed mutagenesis --- p.43 / Chapter 2.9.3 --- Primers used in real-time chain polymerase reaction --- p.43 / Chapter CHAPTER 3 --- RESEARCH METHODS / Chapter 3.1 --- Subcloning of HBx and mutant genes into a green fluorescence protein (GFP) expression vector / Chapter 3.1.1 --- Amplification of HBxWt,HBxΔC44 and HBxAN60 genes --- p.45 / Chapter 3.1.2 --- Purification of PCR products --- p.46 / Chapter 3.1.3 --- Restriction enzyme digestion --- p.47 / Chapter 3.1.4 --- Ligation of gene products with pEGFP-C 1 vector --- p.47 / Chapter 3.1.5 --- Preparation of chemically competent bacterial cells E. coli strain DH5α --- p.47 / Chapter 3.1.6 --- Transformation of the ligation product into competent cells --- p.48 / Chapter 3.1.7 --- PCR confirmation of successful ligation --- p.48 / Chapter 3.1.8 --- Small scale preparation of bacterial plasmid DNA --- p.49 / Chapter 3.1.9 --- DNA sequencing of the cloned plasmid DNA --- p.50 / Chapter 3.1.10 --- Large scale preparation of target recombinant plasmid DNA --- p.50 / Chapter 3.2 --- Subcellular localization pattern study / Chapter 3.2.1 --- Cell transfection --- p.51 / Chapter 3.2.2 --- Mitochondria and nucleus staining --- p.52 / Chapter 3.2.3 --- Epi-fluorescence microscopy --- p.53 / Chapter 3.2.4 --- Analysis of fluorescence images --- p.53 / Chapter 3.2.5 --- In vitro site-directed mutagenesis --- p.53 / Chapter 3.3 --- Cell cycle phase analysis with flow cytometry / Chapter 3.3.1 --- Cell transfection --- p.55 / Chapter 3.3.2 --- Cell staining --- p.55 / Chapter 3.3.3 --- Flow cytometry --- p.55 / Chapter 3.4 --- Cellular proliferation quantification by BrdU proliferation assay / Chapter 3.4.1 --- Cell transfection --- p.57 / Chapter 3.4.2 --- BrdU ELISA measurement --- p.57 / Chapter 3.5 --- Protein expression / Chapter 3.5.1 --- Cell lysate collection --- p.58 / Chapter 3.5.2 --- Quantification of protein samples --- p.59 / Chapter 3.5.3 --- SDS-PAGE --- p.59 / Chapter 3.5.4 --- Western blot --- p.60 / Chapter 3.5.5 --- Western blot luminal detection --- p.60 / Chapter 3.6 --- Gene expression / Chapter 3.6.1 --- Primer design --- p.61 / Chapter 3.6.2 --- Cell transfection --- p.61 / Chapter 3.6.3 --- RNA extraction --- p.61 / Chapter 3.6.4 --- Reverse transcription for first strand complementary DNA (cDNA) --- p.63 / Chapter 3.6.5 --- Quantitative real-time PCR --- p.63 / Chapter 3.7 --- Establishment of Tet-On inducible stable cell-lines / Chapter 3.7.1 --- Subcloning of HBx gene into pTRE2 vector --- p.64 / Chapter 3.7.2 --- Construction of WRL68/Tet-On stable cell-lines --- p.64 / Chapter 3.7.3 --- Construction of WRL68/Tet-On HBx and mutants expression cell-lines --- p.68 / Chapter 3.7.4 --- Characterization of Tet-On gene expression monoclones --- p.69 / Chapter 3.8 --- Statistical analyses --- p.70 / Chapter CHPATER 4 --- STUDY ON MITOCHONDRIA TARGETING / Chapter 4.1 --- Establishment of pEGFP-Cl-HBx and mutants constructs --- p.71 / Chapter 4.2 --- Transactivation C-terminus domain is essential for granular localization --- p.73 / Chapter 4.3 --- Wild-type HBx localizes in mitochondria --- p.76 / Chapter 4.4 --- C-terminal transactivation domain is sufficient for mitochondria targeting --- p.79 / Chapter 4.5 --- Mapping of the HBx region crucial for mitochondria targeting --- p.81 / Chapter 4.6 --- The 111-117 amino acids in HBx do not work as a signal peptide --- p.83 / Chapter 4.7 --- Site-directed mutagenesis identifies the key amino acid at 115 in HBx for mitochondrial targeting --- p.85 / Chapter CHAPTER 5 --- CELL PROLIFERATION AND REGULATION / Chapter 5.1 --- Alteration of S-phase distribution in cell cycle --- p.88 / Chapter 5.2 --- Analysis of DNA synthesis using BrdU proliferation ELISA --- p.92 / Chapter 5.3 --- Differential molecular regulation of cell cycle --- p.94 / Chapter 5.4 --- Regulation of the mRNA expression levels of cyclin-dependent kinases inhibitors p2raf/cipl and p27kipl --- p.98 / Chapter CHAPTER 6 --- TRANSACTIVATION AND RAS/RAF/MAPK PHOSPHORYLATION / Chapter 6.1 --- Determination of p53-dependency of p21、vaf/cipl expression --- p.101 / Chapter 6.2 --- Ras/Raf/MAPK pathway activation by HBx variants / Chapter 6.2.1 --- ERK1/2 phophorylation by HBx variants --- p.104 / Chapter 6.2.2 --- ERK inhibition blocks the regulation effect on p53Wt and p21waf/cipl --- p.107 / Chapter 6.3 --- Transactivation activity on oncogenes/ proto-oncogenes / Chapter 6.3.1 --- Effect on c-myc (NM´ؤ002467) mRNA expression --- p.109 / Chapter 6.3.2 --- Effect on RhoC (NM_017744) and Rabl4 (NM´ؤ016322) mRNA expression --- p.112 / Chapter CHAPTER 7 --- CONSTRUCTION OF TET-ON INDUCIBLE CELL-LINES / Chapter 7.1 --- Establishment of WRL/Tet-On monoclonal cell-lines Page / Chapter 7.1.1 --- Determination of geneticin selection dosage --- p.116 / Chapter 7.1.2 --- Selection of the best WRL/TOn clone using luciferase assay --- p.118 / Chapter 7.2 --- Establishment of inducible WRL/TOn/Gene monoclonal cell-lines / Chapter 7.2.1 --- Determination of hygromycin selection dosage --- p.120 / Chapter 7.2.2 --- Selection of positive WRL/TOn/Gene clones with viral genes --- p.122 / Chapter 7.3 --- Characterization of TOXDC1 cell-line / Chapter 7.3.1 --- Cell morphology --- p.125 / Chapter 7.3.2 --- Growth pattern of TOXDC1 --- p.126 / Chapter 7.3.3 --- HBxAC44 induced p21waf/cipl mRNA expression --- p.127 / Chapter 7.3.4 --- Doxycycline concentration dependent HBxAC44 expression in TOXDC1 --- p.129 / Chapter CHAPTER 8 --- DISCUSSION / Chapter 8.1 --- Selection of cell model / Chapter 8.1.1 --- Selection of cell models --- p.130 / Chapter 8.1.2 --- Selection of truncation mutant --- p.131 / Chapter 8.2 --- Differential sub-cellular localization of HBx and its variants / Chapter 8.2.1 --- Mechanisms of mitochondria targeting --- p.132 / Chapter 8.2.2 --- Mitochondria as site of HBx-induced apoptosis --- p.134 / Chapter 8.2.3 --- Stimulation of calcium release from mitochondria by wild-type HBx --- p.135 / Chapter 8.3 --- Cell cycle distribution profiling and its regulations / Chapter 8.3.1 --- Cell cycle pattern and cell proliferation --- p.136 / Chapter 8.3.2 --- Differential cell cycle molecular pathway activation --- p.138 / Chapter 8.4 --- Ras/Raf/MAPK mediated transactivation by HBxWt and its mutants / Chapter 8.4.1 --- p53-mediated p21waf/cipl expression --- p.142 / Chapter 8.4.2 --- ERK-mediated p21waf/cipl and wild-type p53 mRNA expression --- p.143 / Chapter 8.4.3 --- Regulation of oncogenes/ proto-oncogenes expression --- p.147 / Chapter 8.5 --- General discussions on differential effects of HBxWt and HBxAC44 --- p.149 / Chapter 8.6 --- Establishment of Tet-On/HBxAC44 cell-line TOXDC1 --- p.153 / Chapter 8.7 --- Conclusions --- p.154 / Chapter 8.8 --- Future Prospects / Chapter 8.8.1 --- From mitochondria targeting to calcium signaling --- p.157 / Chapter 8.8.2 --- Construction of a complete cell cycle regulation pathway --- p.158 / Chapter 8.8.3 --- Elucidation of the transcriptional transactivation regulation --- p.159 / Chapter 8.8.4 --- To make the best use of the Tet-on stable cell-line TOXDC1 --- p.159 / Chapter 8.8.5 --- Study with other carboxy-terminal truncation mutants --- p.160 / Chapter 8.8.6 --- In vivo study --- p.160 / REFERENCES --- p.162
248

Effect of HBX on oxidative stress and apoptosis in hepatocellular carcinoma.

January 2007 (has links)
Leung, Chung Yan. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2007. / Includes bibliographical references (leaves 100-113). / Abstracts in English and Chinese. / Abstract --- p.I / 摘要 --- p.III / Acknowledgements --- p.V / List of figures --- p.VI / List of tables --- p.VIII / Abbreviations --- p.IX / Table of Contents --- p.XII / Chapter Chapter 1: --- Introduction / Chapter 1.1 --- Epidemiology of hepatocellular carcinoma (HCC) --- p.1 / Chapter 1.2 --- Etiology of heptocellular carcinoma (HCC) --- p.1 / Chapter 1.3 --- HBV genome structure --- p.2 / Chapter 1.4 --- HBV pathogenesis --- p.2 / Chapter 1.5 --- Hepatitis B virus X protein (HBx) --- p.3 / Chapter 1.6 --- Oxidative stress and antioxidant --- p.5 / Chapter 1.6.1 --- Glutathione (GSH) --- p.5 / Chapter 1.6.2 --- Superoxide dismutase (SOD) --- p.7 / Chapter 1.6.3 --- Oxidative stress in HBV-related liver disease and HCC --- p.8 / Chapter 1.7 --- Apoptosis and necrosis --- p.9 / Chapter 1.7.1 --- Apoptotic pathways --- p.9 / Chapter 1.8 --- Role of HBx in apoptosis --- p.10 / Chapter 1.9 --- Transcriptional activity by HBx --- p.12 / Chapter 1.10 --- Chemotherapy drug resistance --- p.13 / Chapter 1.11 --- Objectives of study --- p.14 / Chapter Chapter 2: --- Methods and materials / Chapter 2.1 --- Construction of plasmid --- p.23 / Chapter 2.1.1 --- PCR amplification of wild-type and mutant HBx --- p.23 / Chapter 2.1.2 --- Agarose gel extraction --- p.25 / Chapter 2.1.3 --- Restriction enzyme digestion --- p.26 / Chapter 2.1.4 --- Ligation of vectors and gene of interest --- p.26 / Chapter 2.1.5 --- Preparation of competent cells for transformation --- p.27 / Chapter 2.1.6 --- Transformation of plasmid in competent cells --- p.27 / Chapter 2.1.7 --- Plasmid extraction by mini-prep --- p.28 / Chapter 2.1.8 --- DNA sequencing of the inserted genes --- p.29 / Chapter 2.2 --- Transfection --- p.30 / Chapter 2.2.1 --- Cell line --- p.30 / Chapter 2.2.2 --- Lipofectamine transfection --- p.31 / Chapter 2.2.3 --- Construction of stably-transfected cell lines --- p.31 / Chapter 2.3 --- Detection of expression of transfected gene in mRNA level by RT-PCR --- p.32 / Chapter 2.3.1 --- RNA extraction --- p.32 / Chapter 2.3.2 --- Reverse transcription-polymerase chain reaction (RT-PCR) --- p.33 / Chapter 2.3.3 --- Agarose gel electrophoresis --- p.36 / Chapter 2.4 --- Detection of expression of transfected gene in protein level by Western blot --- p.36 / Chapter 2.4.1 --- Sample preparation --- p.36 / Chapter 2.4.2 --- Measurement of protein concentration --- p.36 / Chapter 2.4.3 --- Sodium dodecyl sulfate- polyacrylamide gel electrophoresis (SDS-PAGE) --- p.37 / Chapter 2.4.4 --- Transfer of proteins to nitrocellulose membrane --- p.38 / Chapter 2.4.5 --- Immunoblotting of protein --- p.38 / Chapter 2.5 --- Measurement of reduced glutathione (GSH) concentration in cell lines --- p.39 / Chapter 2.5.1 --- Sample preparation --- p.39 / Chapter 2.5.2 --- Measurement of GSH concentration --- p.39 / Chapter 2.6 --- Superoxide dismutase (SOD) activity in cell lines --- p.40 / Chapter 2.6.1 --- Sample preparation --- p.40 / Chapter 2.6.2 --- Measurement of total SOD activity --- p.41 / Chapter 2.6.3 --- Measurement of Cu/ZnSOD and MnSOD by Western blot --- p.42 / Chapter 2.7 --- Cell proliferation assay --- p.43 / Chapter 2.7.1 --- Drugs and concentration --- p.43 / Chapter 2.7.2 --- "MTT(3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide)assay" --- p.43 / Chapter 2.7.3 --- Cell proliferation and cytotoxicity of the drugs --- p.44 / Chapter 2.8 --- Detection of apoptosis by flow-cytometry --- p.44 / Chapter 2.8.1 --- Cell culture --- p.44 / Chapter 2.8.2 --- Cell fixation --- p.45 / Chapter 2.8.3 --- Cell staining --- p.45 / Chapter 2.8.4 --- Flow cytometry analysis --- p.46 / Chapter 2.9 --- Detection of protein involved in apoptotic pathway --- p.46 / Chapter 2.9.1 --- Antibodies --- p.46 / Chapter 2.9.2 --- Sample Preparation --- p.47 / Chapter 2.9.3 --- Measurement of protein concentration --- p.48 / Chapter 2.9.4 --- Western blotting --- p.49 / Chapter Chapter 3: --- Establishment of HBx transfected stable cell lines / Chapter 3.1 --- Introduction --- p.55 / Chapter 3.2 --- Results --- p.56 / Chapter 3.2.1 --- Plasmid construction --- p.56 / Chapter 3.2.2 --- Stable transfection of cell lines --- p.57 / Chapter 3.2.3 --- Morphology of wild type and mutant HBx-transfected cell lines --- p.58 / Chapter 3.3 --- Discussion --- p.58 / Chapter Chapter 4: --- Antioxidant level in HBx transfected cell lines / Chapter 4.1 --- Introduction --- p.68 / Chapter 4.2 --- Results --- p.70 / Chapter 4.2.1 --- Glutathione (GSH) concentration in different cell lines --- p.70 / Chapter 4.2.2 --- Superoxide dismutase (SOD) activity in different cell lines --- p.71 / Chapter 4.2.2.1 --- Total SOD activity --- p.71 / Chapter 4.2.2.2 --- Cu/ZnSOD --- p.71 / Chapter 4.2.2.3 --- MnSOD --- p.72 / Chapter 4.3 --- Discussion --- p.72 / Chapter Chapter 5: --- Involvement of HBx in apoptotic pathway / Chapter 5.1 --- Introduction --- p.81 / Chapter 5.2 --- Results --- p.82 / Chapter 5.2.1 --- Cell proliferation of HBx transfected cells --- p.82 / Chapter 5.2.2 --- Apoptosis of HBx transfected cells --- p.83 / Chapter 5.2.3 --- Cytotoxicity of fluorouracil (5FU) and doxorubicin (DOX) in HBx transfected cells --- p.84 / Chapter 5.2.4 --- Detection of anti-apoptotic proteins cIAP2 and Bcl-2 in HBx-transient and stably transfected cells --- p.84 / Chapter 5.3 --- Discussion --- p.85 / Chapter Chapter 6: --- Concluding remarks and general discussion / Chapter 6.1 --- General discussion --- p.93 / Chapter 6.2 --- Future work --- p.97 / Chapter 6.3 --- Summary --- p.99 / References --- p.100 / Appendix 1 --- p.114
249

Development of a Hepatitis C Virus knowledgebase with computational prediction of functional hypothesis of therapeutic relevance

Kojo, Kwofie Samuel January 2011 (has links)
<p>To ameliorate Hepatitis C Virus (HCV) therapeutic and diagnostic challenges requires robust intervention strategies, including approaches that leverage the plethora of rich data published in biomedical literature to gain greater understanding of HCV pathobiological mechanisms. The multitudes of metadata originating from HCV clinical trials as well as low and high-throughput experiments embedded in text corpora can be mined as data sources for the implementation of HCV-specific resources. HCV-customized resources may support the generation of worthy and testable hypothesis and reveal potential research clues to augment the pursuit of efficient diagnostic biomarkers and therapeutic targets. This research thesis report the development of two freely available HCV-specific web-based resources: (i) Dragon Exploratory System on Hepatitis C Virus (DESHCV) accessible via http://apps.sanbi.ac.za/DESHCV/ or http://cbrc.kaust.edu.sa/deshcv/ and (ii) Hepatitis C Virus Protein Interaction Database (HCVpro) accessible via&nbsp / http://apps.sanbi.ac.za/hcvpro/ or http://cbrc.kaust.edu.sa/hcvpro/. DESHCV is a text mining system implemented using named concept recognition and cooccurrence based&nbsp / approaches to computationally analyze about 32, 000 HCV related abstracts obtained from PubMed. As part of DESHCV development, the pre-constructed dictionaries of the&nbsp / Dragon Exploratory System (DES) were enriched with HCV biomedical concepts, including HCV proteins, name variants and symbols to enable HCV knowledge specific&nbsp / exploration. The DESHCV query inputs consist of user-defined keywords, phrases and concepts. DESHCV is therefore an information extraction tool that enables users to&nbsp / computationally generate association between concepts and support the prediction of potential hypothesis with diagnostic and therapeutic relevance. Additionally, users can&nbsp / retrieve a list of abstracts containing tagged concepts that can be used to overcome the herculean task of manual biocuration. DESHCV has been used to simulate previously&nbsp / reported thalidomide-chronic hepatitis C hypothesis and also to model a potentially novel thalidomide-amantadine hypothesis. HCVpro is a relational knowledgebase dedicated to housing experimentally detected HCV-HCV and HCV-human protein interaction information obtained from other databases and curated from biomedical journal articles.&nbsp / Additionally, the database contains consolidated biological information consisting of hepatocellular carcinoma (HCC) related genes, comprehensive reviews on HCV biology and drug development, functional genomics and molecular biology data, and cross-referenced links to canonical pathways and other essential biomedical databases. Users can retrieve enriched information including interaction metadata from HCVpro by using protein identifiers, gene chromosomal locations, experiment types used in detecting the interactions, PubMed IDs of journal articles reporting the interactions, annotated protein interaction IDs from external databases, and via &ldquo / string searches&rdquo / . The utility of HCVpro&nbsp / has been demonstrated by harnessing integrated data to suggest putative baseline clues that seem to support current diagnostic exploratory efforts directed towards vimentin.&nbsp / Furthermore, eight genes comprising of ACLY, AZGP1, DDX3X, FGG, H19, SIAH1, SERPING1 and THBS1 have been recommended for possible investigation to evaluate their&nbsp / diagnostic potential. The data archived in HCVpro can be&nbsp / utilized to support protein-protein interaction network-based candidate HCC gene prioritization for possible validation by experimental biologists.&nbsp / </p>
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Risk Factors for Extended Hospital Stay in Transcatheter Arterial Chemoembolization for Hepatocellular Carcinoma

Lin, Jau-Nan 29 June 2011 (has links)
Hepatocellular carcinoma (HCC) is the second most common cancer in Taiwan and transcatheter arterial chemoembolization (TACE) is now the mainstay of treatment for noncurative HCC. Due to increasing medical costs yearly and financial problem of the Bureau of National Health Insurance, it is important to reduce medical resource utilization including hospital stay and medical costs. The aim is to figure out the risk factors of extended hospital stay, and increased in-hospital medical costs in hepatocellular carcinoma patients receiving transcatheter arterial chemoembolization. The result of this study should be available for further improvement of medical care quality in the limited medical resource. From January 2008 to January 2010, 162 patients (121 male and 41 female) with histologically proven hepatocellular carcinoma underwent TACE only (131 pts) or TACE followed by catheter placement for hepatic artery infusion chemotherapy (HAIC) (31pts) at district teaching hospital. The extended hospital stay (EHS) and extended post-procedure stay (EPS) are defined as stay larger than their median values (11 & 7 days respectively). Clinical demographic, disease factors, tumor factors, procedure (TACE)-related factors and complications are used to identify the univariate factors related to EHS and EPS statistically. To find out predictors of EHS, EPS and increased in-hospital medical costs, multiple linear regression analyses are used. The risk factors for EPS are procedure-related, including complications and procedure methods ( TACE + HAIC related to TACE only) (R2=.367, p<.001), while those for EHS are complications, encephalopathy, procedure methods, Child-Pugh classification C (related to classification A) and age (R2=.490, p<.001). The predictors for increased in-hospital medical costs include procedure methods, AJCC stage IV, T4 stage, hepatoencephalopathy and complications (R2=0.615, p<.001). Taking total hospital stay into consideration, the most important risk factor related to increased medical cost is total hosptial stay itself. The most powerful risk factor for EPS, EHS is procedure-related complication. The different procedure methods also affect hospital stay and medical costs. In order to reduce medical resource utilization, we should avoid post-procedure complication and pay attention to cirrhotic degree as well as American Joint Committee of Cancer (AJCC) tumor stage system. The result of this study can provide some ideas to adjust medical expense polices for the Bureau of National Health Insurance and to control medical cost for the hospitals.

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