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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.
131

The effect of 5-fluorouracil on the mRNA and proteins expression in a human colon cancer cell line SW480.

January 2007 (has links)
Wong, Wai Ki Vicky. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2007. / Includes bibliographical references (leaves 105-131). / Abstracts in English and Chinese. / Abstract --- p.ii / 摘要 --- p.iv / Acknowledgements --- p.vi / Table of contents --- p.vii / List of tables --- p.xii / List of figures --- p.xiii / List of abbreviations --- p.xiv / Chapter Chapter 1: --- Introduction --- p.1 / Chapter Chapter 2: --- Colorectal cancer / Chapter 2.1 --- Literature Review / Chapter 2.1.1 --- Colorectal cancer --- p.8 / Chapter 2.1.2 --- Incident rate of colorectal cancer --- p.8 / Chapter 2.1.3 --- Hereditary colorectal cancer --- p.9 / Chapter 2.1.4 --- Sporadic colorectal cancer and Wnt signaling pathway --- p.10 / Chapter 2.1.5 --- Chemotherapy treatment of colorectal cancer --- p.11 / Chapter 2.1.5.1 --- 5-Fluorouracil --- p.12 / Chapter 2.1.5.2 --- Oxaliplatin --- p.14 / Chapter 2.1.5.3 --- Irinotecan --- p.14 / Chapter 2.1.6 --- Biomarkers for colorectal cancer --- p.15 / Chapter 2.1.6.1 --- Thymidylate synthase --- p.15 / Chapter 2.1.6.2 --- Dihydropyrimidine dehydrogenase --- p.16 / Chapter 2.1.6.3 --- Thymidine phosphorylase --- p.16 / Chapter 2.1.6.4 --- Microsatellite-instability status --- p.16 / Chapter 2.1.6.5 --- Clinical uses of biomarkers for colorectal cancer --- p.17 / Chapter 2.1.7 --- Choice of cell line as colorectal cancer model --- p.17 / Chapter 2.1.8 --- Aims of study --- p.17 / Chapter 2.2 --- Materials and Methods / Chapter 2.2.1 --- Verification of SW480 as a nuclear β-catenin positive cell line / Chapter 2.2.1.1 --- Maintenance of cell lines --- p.21 / Chapter 2.2.1.2 --- Antibody --- p.21 / Chapter 2.2.1.3 --- Agar block preparation for SW480 and CCD-18C0 cells --- p.22 / Chapter 2.2.1.4 --- Immunocytochemical staining --- p.22 / Chapter 2.2.2 --- Effect of anti-cancer drugs on cell viability / Chapter 2.2.2.1 --- Maintenance of cell lines --- p.22 / Chapter 2.2.2.2 --- MTT cell viability assay --- p.23 / Chapter 2.3 --- Results / Chapter 2.3.1 --- SW480 is a β-catenin positive cell line --- p.24 / Chapter 2.3.2 --- Antiproliferative effects of cytotoxic drugs in SW480 cells / Chapter 2.3.2.1 --- 5-Fluorouracil --- p.26 / Chapter 2.3.2.2 --- Oxaliplatin --- p.29 / Chapter 2.3.2.3 --- Irinotecan --- p.31 / Chapter 2.4 --- Discussion / Chapter 2.4.1 --- SW480 as a nuclear β-catenin positive cell line --- p.33 / Chapter 2.4.2 --- Antiproliferative effects of 5-fluorouracil in SW480 cells --- p.33 / Chapter 2.4.3 --- Summary --- p.34 / Chapter Chapter 3: --- Effect of 5-fluorouracil on mRNA expression in SW480 cells / Chapter 3.1 --- Literature Review / Chapter 3.1.1 --- Application of quantitative real-time polymerase chain reaction in cancer research / Chapter 3.1.1.1 --- Principles of quantitative real-time polymerase chain reaction --- p.36 / Chapter 3.1.1.2 --- Advantages of quantitative real-time polymerase chain reaction over conventional polymerase chain reaction --- p.39 / Chapter 3.1.1.3 --- Determination of colorectal cancer biomarkers by quantitative real-time polymerase chain reaction --- p.39 / Chapter 3.2 --- Materials and Methods / Chapter 3.2.1 --- Determination of the effect of 5-fluorouracil on mRNA expression in SW480 cells / Chapter 3.2.1.1 --- Treatment of cells --- p.40 / Chapter 3.2.1.2 --- Extraction of total RNA from SW480 cells --- p.40 / Chapter 3.2.1.3 --- Removal of genomic DNA --- p.41 / Chapter 3.2.1.4 --- Determination of the efficiency of genomic DNA removal --- p.42 / Chapter 3.2.1.5 --- Determination of the purity and concentration of RNA --- p.42 / Chapter 3.2.1.6 --- Determination of the integrity of RNA --- p.43 / Chapter 3.2.1.7 --- First strand cDNA synthesis --- p.44 / Chapter 3.2.1.8 --- Real-time polymerase chain reaction using human Wnt signaling pathway RT2 ProfileŕёØ PCR array --- p.44 / Chapter 3.2.1.9 --- Calculation of the fold-change in genes expression between the 5-FU treated and control SW480 cells --- p.45 / Chapter 3.3 --- Results / Chapter 3.3.1 --- The quality and quantity of RNA --- p.46 / Chapter 3.3.2 --- Effects of 5-fluorouracil on genes expression in SW480 cells --- p.48 / Chapter 3.4 --- Discussion / Chapter 3.4.1 --- Alterations in mRNA expression in 5-fluorouracil treated SW480 cells --- p.55 / Chapter 3.4.1.1 --- Extracellular signaling molecules --- p.55 / Chapter 3.4.1.2 --- Canonical Wnt signaling pathway --- p.56 / Chapter 3.4.1.3 --- Regulators of cell cycle --- p.57 / Chapter 3.4.1.4 --- Regulators of growth and proliferation --- p.58 / Chapter 3.4.1.5 --- Regulators of transcription --- p.58 / Chapter 3.4.1.6 --- Regulators of Wnt receptor signaling pathway --- p.60 / Chapter 3.4.1.7 --- Other genes involved in Wnt signaling --- p.61 / Chapter 3.4.2 --- Limitations of Q-RT-PCR --- p.61 / Chapter 3.4.3 --- Summary --- p.62 / Chapter Chapter 4: --- Effect of 5-fluorouracil on proteins expression in SW480 cells / Chapter 4.1 --- Literature Review / Chapter 4.1.1 --- From mRNA to proteins --- p.63 / Chapter 4.1.2 --- Application of proteomics in cancer research --- p.63 / Chapter 4.1.3 --- Two-dimensional gel electrophoresis --- p.64 / Chapter 4.1.4 --- Principles of MALDI TOF mass spectrometry --- p.64 / Chapter 4.1.5 --- Peptide mass fingerprinting --- p.65 / Chapter 4.1.6 --- Drug response proteins detected by proteomics in colorectal cancer cell lines --- p.65 / Chapter 4.1.7 --- Detection of biomarker in colorectal cancer formation using proteomics --- p.66 / Chapter 4.2 --- Materials and Methods / Chapter 4.2.1 --- Determination of the effect of 5-fluorouracil on proteins expression in SW480 cells / Chapter 4.2.1.1 --- Treatment of cells --- p.67 / Chapter 4.2.1.2 --- Cell lysis --- p.67 / Chapter 4.2.1.3 --- Protein quantitation of cell lysate --- p.67 / Chapter 4.2.1.4 --- Sample preparation for two-dimensional electrophoresis --- p.68 / Chapter 4.2.1.5 --- Two-dimensional electrophoresis --- p.69 / Chapter 4.2.1.6 --- Silver staining --- p.69 / Chapter 4.2.1.7 --- Image analysis --- p.70 / Chapter 4.2.1.8 --- In-gel protein digestion --- p.70 / Chapter 4.2.1.9 --- Peptide mass fingerprinting using mass spectrometry --- p.71 / Chapter 4.3 --- Results / Chapter 4.3.1 --- Protein expression patterns of 5-fluorouracil treated and untreated SW480 cells by 2-dimensional electrophoresis --- p.72 / Chapter 4.3.2 --- Identification of the differentially expressed proteins after 5-fluorouracil treatment in SW480 cells --- p.75 / Chapter 4.4 --- Discussion / Chapter 4.4.1 --- Effects of 5-fluorouracil on protein expression in SW480 cells --- p.82 / Chapter 4.4.1.1 --- Identified upregulated proteins after 5-fluorouracil treatment in SW480 cells / Chapter 4.4.1.1.1 --- Cyclophilin A --- p.83 / Chapter 4.4.1.1.2 --- Cytokeratin 19 --- p.83 / Chapter 4.4.1.1.3 --- Cytokeratin 8 --- p.84 / Chapter 4.4.1.1.4 --- RAN --- p.84 / Chapter 4.4.1.1.5 --- Heat shock protein 27 --- p.84 / Chapter 4.4.1.1.6 --- Peroxiredoxin 6 --- p.85 / Chapter 4.4.1.2 --- Identified dowiiregulated proteins after 5-fluorouracil treatment in SW480 cells / Chapter 4.4.1.2.1 --- Heat shock protein 60 --- p.86 / Chapter 4.4.1.2.2 --- Cytokeratin 18 --- p.86 / Chapter 4.4.1.2.3 --- Cytokeratin 9 --- p.86 / Chapter 4.4.1.2.4 --- Carbamoylphosphate synthetase I --- p.87 / Chapter 4.4.1.2.5 --- a-Enolase --- p.87 / Chapter 4.4.1.2.6 --- Heat shock protein 70 --- p.87 / Chapter 4.4.1.2.7 --- nm23 --- p.88 / Chapter 4.4.1.2.8 --- β-actin --- p.88 / Chapter 4.4.2 --- Limitations of proteomics profiling --- p.89 / Chapter 4.4.3 --- Summary --- p.90 / Chapter Chapter 5: --- Verification of proteinśة identities by immunocytochemical staining / Chapter 5.1 --- Materials and Methods / Chapter 5.1.1 --- Antibodies --- p.91 / Chapter 5.1.2 --- Treatment of cells --- p.91 / Chapter 5.1.3 --- Agar block preparation of SW480 cells --- p.92 / Chapter 5.1.4 --- Immunocytochemical staining and evaluation --- p.92 / Chapter 5.1.5 --- Polymer-based immunohistochemical detection system --- p.93 / Chapter 5.1.6 --- Statistical analyses --- p.93 / Chapter 5.2 --- Results / Chapter 5.2.1 --- Confirmation of proteomic findings using immunocytochemical stainings in paraffin-embedded sections of 5-fluorouracil treated and untreated SW480 cells --- p.94 / Chapter 5.3 --- Discussion / Chapter 5.3.1 --- Immunocytochemical staining to verify proteomics findings of 5-fluorouracil treated and untreated SW480 cells --- p.99 / Chapter 5.3.2 --- Limitations of ICC staining --- p.100 / Chapter 5.3.3 --- Summary --- p.100 / Chapter Chapter 6: --- Conclusions and future perspectives / Chapter 6.1 --- Significance of study --- p.101 / Chapter 6.2 --- Future perspectives --- p.102 / References --- p.105
132

Head and neck cancer : factors affecting tumour growth /

Sundelin, Kaarina, January 2007 (has links) (PDF)
Diss. (sammanfattning) Linköping : Linköpings universitet, 2007. / Härtill 4 uppsatser.
133

Comparação da expressão gênica do KRAS mutante, KU70, TACSTD2 e SERIN1 em tecidos tumoral e normal de pacientes com câncer colorretal pela técnica de PCR em tempo real / The comparison of the gene expression of mutant KRAS, KU70, TACSTD2 and SERIN1 in the tumoral and normal tissues of patients with colorectal cancer through the technique of PCR in real time

Ghezzi, Tiago Leal January 2010 (has links)
INTRODUÇÃO: O estudo das vias moleculares e das alterações específicas responsáveis pela progressão desfavorável de pacientes com CCR parece essencial para o desenvolvimento de terapias mais efetivas. OBJETIVO: Comparar a expressão quantitativa dos genes TACSTD2, Ku70, KRAS mutante e SERIN1 em amostras de tecidos normal e tumoral de pacientes com CCR e relacionar sua expressão com variáveis clínico-patológicas. MÉTODOS: Foram estudados 37 pacientes com CCR submetidos à ressecção cirúrgica entre julho de 2005 e julho de 2009 e cujas amostras congeladas de tecidos tumoral e normal foram armazenadas em um banco de tecidos. Através da RT-PCR foi sintetizado o cDNA a partir do RNA extraído das amostras teciduais. A expressão dos genes TACSTD2, KRAS mutante, Ku70 e SERIN1 foi quantificada pela técnica de PCR em tempo real. RESULTADOS: A expressão do KRAS mutante foi maior no tecido tumoral do que no normal (p = 0,024). A expressão tumoral dos genes Ku70, TACSTD2 e SERIN1 foi respectivamente menor, igual e maior que o tecido normal, porém sem significância estatística. Associação estatisticamente significativa também foi observada entre idade e expressão de KRAS mutante no tecido normal e tumores pouco diferenciados e expressão de Ku70 no tecido normal. Não foram observadas outras associações estatisticamente significativas. CONCLUSÕES: A expressão do KRAS mutante no tecido tumoral é maior do que no tecido normal (p = 0,024) na casuística de 37 pacientes com CCR estudados através da técnica de PCR em tempo real. / INTRODUCTION: Knowledge of the molecular pathways and of the specific alterations responsible for the unfavorable progression of patients with CCR appears essential for the development of more effective therapies. PURPOSE: To compare the quantitative expression of the genes TACSTD2, mutant KRAS, Ku70 and SERIN1 in samples of normal and tumoral tissues of patients with CCR and to relate their expression to clinicopathologic characteristics. METHODS: 37 patients with CCR were studied. The patients had been operated on between July 2005 and July 2009, and their frozen samples of tumoral and normal tissues had been stored in a tissue bank. The expression of the genes TACSTD2, mutant KRAS, Ku70 and SERIN1 was quantified through the technique of real time polymerase chain reaction. RESULTS: The mutant KRAS expression was higher in the tumoral tissue than in the normal tissue (p = 0,024). Although not significant, the tumoral expression of the genes Ku70, TACSTD2 and SERIN1 was respectively lower, equal to, and higher than in the normal tissue. Statistically significant association was also observed between age and mutant KRAS expression in normal tissue and between poorly-differentiated tumors and Ku70 expression in normal tissue. No other statistically significant associations were observed. CONCLUSIONS: Tumoral tissues express mutant KRAS at higher levels than normal tissues in the casuistic of 37 patients with CCR studied through the technique of PCR real time.
134

Avaliação da expressão da proteína p53 e do VEGF (Fator de Crescimento do Endotélio Vascular) em pacientes com adenocarcinoma de esôfago / Evaluation of p53 protein and VEGF (vascular Endothelial Growth Factor) expresion in patients with esophageal adenocarcinoma

Cavazzola, Leandro Totti January 2004 (has links)
O prognóstico dos pacientes com adenocarcinoma de esôfago é bastante prejudicado pelo seu diagnóstico tardio. Na tentativa de determinar fatores que possam alterar o prognóstico destes pacientes, o estudo da biologia molecular tem recebido grande importância. As mutações no gene de supressão tumoral TP53 estão entre as anormalidades genéticas mais comuns encontradas numa ampla variedade de tumores. A angiogênese é essencial para o crescimento e a metastatização de tumores sólidos. O Fator de Crescimento do Endotélio Vascular (VEGF, Vascular Endothelial Growth Factor), um fator de crescimento identificado recentemente com propriedades angiogênicas significativas, pode ser um importante regulador desta angiogênese tumoral. A associação entre as expressões da proteína p53 e do VEGF e o prognóstico tem sido pouco estudada. Foram estudados 46 pacientes com adenocarcinoma de esôfago submetidos à cirurgia de ressecção com intenção curativa. As expressões da proteína p53 e do VEGF foram observadas por análise imuno-histoqímica em 52,2% e 47,8% dos tumores, respectivamente. As expressões da proteína p53 e do VEGF coincidiram em 26% dos casos, e não foi encontrada correlação entre essa expressão. Nenhum dos fatores clinicopatológicos se correlacionaram significativamente com as expressões da proteína p53 ou do VEGF. Não houve associação significativa entre as expressões da proteína p53 e do VEGF e sobrevida a longo prazo. No presente estudo, a expressão da proteína p53 e do VEGF, embora em porcentagem similar à da literatura, não se correlacionou com o prognóstico em pacientes com adenocarcinoma de esôfago submetidos à cirurgia com intenção curativa. / The prognosis of patients with esophageal adenocarcinoma is negatively influenced by late diagnosis. In an attempt to determine the factors that might improve the prognosis of these patients, molecular biology has been of great importance. P53 tumor suppressor gene mutations are one of the most frequent genetic disorders found in a wide variety of tumors. Angiogenesis is essential for the growth and metastatic spread of solid tumors. The Vascular Endothelial Growth Factor (VEGF), a recently identified factor with remarkable angiogenic properties, may play a central regulatory role in tumor angiogenesis. The association between p53 protein and VEGF expressions and prognosis has been underinvestigated. Forty-six patients with esophageal adenocarcinoma, submitted to curative resection, were studied. The expressions of p53 protein and VEGF were assessed by immunohistochemistry in 52.2% and 47.8% of tumors, respectively. P53 protein and VEGF expressions coincided in 26% of the cases, and no correlation between these expressions was observed. None of the clinicopathological factors showed a significant correlation with p53 protein or VEGF expressions. There was no significant association between p53 protein and VEGF expressions and long-term survival. In the present study, the expression of p53 protein and VEGF, albeit similar to the one reported in the literature, did not correlate with prognosis in esophageal adenocarcinoma patients submitted to curative resection.
135

Comparação da expressão gênica do KRAS mutante, KU70, TACSTD2 e SERIN1 em tecidos tumoral e normal de pacientes com câncer colorretal pela técnica de PCR em tempo real / The comparison of the gene expression of mutant KRAS, KU70, TACSTD2 and SERIN1 in the tumoral and normal tissues of patients with colorectal cancer through the technique of PCR in real time

Ghezzi, Tiago Leal January 2010 (has links)
INTRODUÇÃO: O estudo das vias moleculares e das alterações específicas responsáveis pela progressão desfavorável de pacientes com CCR parece essencial para o desenvolvimento de terapias mais efetivas. OBJETIVO: Comparar a expressão quantitativa dos genes TACSTD2, Ku70, KRAS mutante e SERIN1 em amostras de tecidos normal e tumoral de pacientes com CCR e relacionar sua expressão com variáveis clínico-patológicas. MÉTODOS: Foram estudados 37 pacientes com CCR submetidos à ressecção cirúrgica entre julho de 2005 e julho de 2009 e cujas amostras congeladas de tecidos tumoral e normal foram armazenadas em um banco de tecidos. Através da RT-PCR foi sintetizado o cDNA a partir do RNA extraído das amostras teciduais. A expressão dos genes TACSTD2, KRAS mutante, Ku70 e SERIN1 foi quantificada pela técnica de PCR em tempo real. RESULTADOS: A expressão do KRAS mutante foi maior no tecido tumoral do que no normal (p = 0,024). A expressão tumoral dos genes Ku70, TACSTD2 e SERIN1 foi respectivamente menor, igual e maior que o tecido normal, porém sem significância estatística. Associação estatisticamente significativa também foi observada entre idade e expressão de KRAS mutante no tecido normal e tumores pouco diferenciados e expressão de Ku70 no tecido normal. Não foram observadas outras associações estatisticamente significativas. CONCLUSÕES: A expressão do KRAS mutante no tecido tumoral é maior do que no tecido normal (p = 0,024) na casuística de 37 pacientes com CCR estudados através da técnica de PCR em tempo real. / INTRODUCTION: Knowledge of the molecular pathways and of the specific alterations responsible for the unfavorable progression of patients with CCR appears essential for the development of more effective therapies. PURPOSE: To compare the quantitative expression of the genes TACSTD2, mutant KRAS, Ku70 and SERIN1 in samples of normal and tumoral tissues of patients with CCR and to relate their expression to clinicopathologic characteristics. METHODS: 37 patients with CCR were studied. The patients had been operated on between July 2005 and July 2009, and their frozen samples of tumoral and normal tissues had been stored in a tissue bank. The expression of the genes TACSTD2, mutant KRAS, Ku70 and SERIN1 was quantified through the technique of real time polymerase chain reaction. RESULTS: The mutant KRAS expression was higher in the tumoral tissue than in the normal tissue (p = 0,024). Although not significant, the tumoral expression of the genes Ku70, TACSTD2 and SERIN1 was respectively lower, equal to, and higher than in the normal tissue. Statistically significant association was also observed between age and mutant KRAS expression in normal tissue and between poorly-differentiated tumors and Ku70 expression in normal tissue. No other statistically significant associations were observed. CONCLUSIONS: Tumoral tissues express mutant KRAS at higher levels than normal tissues in the casuistic of 37 patients with CCR studied through the technique of PCR real time.
136

Avaliação da expressão da proteína p53 e do VEGF (Fator de Crescimento do Endotélio Vascular) em pacientes com adenocarcinoma de esôfago / Evaluation of p53 protein and VEGF (vascular Endothelial Growth Factor) expresion in patients with esophageal adenocarcinoma

Cavazzola, Leandro Totti January 2004 (has links)
O prognóstico dos pacientes com adenocarcinoma de esôfago é bastante prejudicado pelo seu diagnóstico tardio. Na tentativa de determinar fatores que possam alterar o prognóstico destes pacientes, o estudo da biologia molecular tem recebido grande importância. As mutações no gene de supressão tumoral TP53 estão entre as anormalidades genéticas mais comuns encontradas numa ampla variedade de tumores. A angiogênese é essencial para o crescimento e a metastatização de tumores sólidos. O Fator de Crescimento do Endotélio Vascular (VEGF, Vascular Endothelial Growth Factor), um fator de crescimento identificado recentemente com propriedades angiogênicas significativas, pode ser um importante regulador desta angiogênese tumoral. A associação entre as expressões da proteína p53 e do VEGF e o prognóstico tem sido pouco estudada. Foram estudados 46 pacientes com adenocarcinoma de esôfago submetidos à cirurgia de ressecção com intenção curativa. As expressões da proteína p53 e do VEGF foram observadas por análise imuno-histoqímica em 52,2% e 47,8% dos tumores, respectivamente. As expressões da proteína p53 e do VEGF coincidiram em 26% dos casos, e não foi encontrada correlação entre essa expressão. Nenhum dos fatores clinicopatológicos se correlacionaram significativamente com as expressões da proteína p53 ou do VEGF. Não houve associação significativa entre as expressões da proteína p53 e do VEGF e sobrevida a longo prazo. No presente estudo, a expressão da proteína p53 e do VEGF, embora em porcentagem similar à da literatura, não se correlacionou com o prognóstico em pacientes com adenocarcinoma de esôfago submetidos à cirurgia com intenção curativa. / The prognosis of patients with esophageal adenocarcinoma is negatively influenced by late diagnosis. In an attempt to determine the factors that might improve the prognosis of these patients, molecular biology has been of great importance. P53 tumor suppressor gene mutations are one of the most frequent genetic disorders found in a wide variety of tumors. Angiogenesis is essential for the growth and metastatic spread of solid tumors. The Vascular Endothelial Growth Factor (VEGF), a recently identified factor with remarkable angiogenic properties, may play a central regulatory role in tumor angiogenesis. The association between p53 protein and VEGF expressions and prognosis has been underinvestigated. Forty-six patients with esophageal adenocarcinoma, submitted to curative resection, were studied. The expressions of p53 protein and VEGF were assessed by immunohistochemistry in 52.2% and 47.8% of tumors, respectively. P53 protein and VEGF expressions coincided in 26% of the cases, and no correlation between these expressions was observed. None of the clinicopathological factors showed a significant correlation with p53 protein or VEGF expressions. There was no significant association between p53 protein and VEGF expressions and long-term survival. In the present study, the expression of p53 protein and VEGF, albeit similar to the one reported in the literature, did not correlate with prognosis in esophageal adenocarcinoma patients submitted to curative resection.
137

Desenvolvimento de aplicações tecnológicas da metodologia de phage display no diagnóstico do câncer de próstata

Freschi, Ana Paula Peres 28 November 2006 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Prostate cancer is the second cause of death in men by tumor, surpassed only by lung cancer. Its occurrence is estimated to be 51 to 100,000 cases per year. The increasing incidence levels observed may be partially explained by the evolution of diagnostic methods, quality of information systems and longer life expectancy. The identification of new cancer specific antigens and genes may provide important biomarkers for diagnosis and instruments for the development of new treatment strategies. The Phage Display technology may be able to select peptides with different aims, such as the discovery of mimetic antigens that are recognized by specific antibodies. Selected peptides may become potential tumor biomarkers for prostate cancer diagnosis. It could be possible to use this technology to identify proteins that are able to detect cancer earlier than the conventional methods, to predict disease staging, and to develop new treatment strategies based on more efficient biological targets. The immunization of SPF (specific pathogen free) male chickens with total proteins of tissues of prostate cancer has generated polyclonal specific IgY sera, which were used in biopanning procedures against random peptide libraries. Selected phages were characterized by sequencing and bioinformatics, and subsequently by dot immunoblotting and ELISA to validate their specificity. Selected peptides were mimotopes of putative proteins involved in the carcinogenesis process. These peptides were further tested for their possible use in the immune response diagnostics associated with tumor processes. In this work, we have also successfully developed a general immunosensor for diagnostics, performed on an exclusion liquid chromatography system based on a micro column resin separation, using the selected bacteriophages as carriers of antigens and antibodies. These phage are coupled to colored latex beads, which are activated with different chemical groups. The presence of phage in the process is of fundamental importance, once they favor the formation of the antigen-antibody complex, peptide-protein or peptide-substrate, amplifying the optical detection during chromatographic separation or by micro-agglutination in slides for optical microscopy detection. The new technology is practical and simple, and may also be used for detection of other biomolecules or chemical substances associated with infectious and genetic diseases, with high precision, sensitivity, specificity, and rapidity, using low sample volumes and presenting a low cost. / O câncer de próstata é a segunda causa de óbitos por câncer em homens, sendo superado apenas pelo câncer de pulmão. A ocorrência estimada é de 51 casos novos para cada 100 mil homens por ano para este tipo de câncer. O aumento observado nas taxas de incidência pode ser parcialmente justificado pela evolução dos métodos diagnósticos, pela melhoria na qualidade dos sistemas de informação do país e pelo aumento na expectativa de vida do brasileiro. A identificação de novos antígenos ou genes específicos do câncer de próstata pode prover novos biomarcadores e também fornecer instrumentos para o desenvolvimento de novas modalidades de tratamento. A tecnologia de Phage Display é capaz de selecionar peptídeos com diversas finalidades, como mimetizar antígenos reconhecidos por anticorpos. Peptídeos selecionados por esta técnica são potenciais marcadores tumorais para o diagnóstico do câncer de próstata. Por meio desta metodologia pode ser possível identificar proteínas capazes de detectar a resposta imune contra o tumor mais precocemente do que os métodos tradicionais, predizer o estadio atual do tumor, além de permitir o desenvolvimento de tratamentos mais eficientes. Pela imunização de galos SPF (livre de patógenos específicos) com proteínas totais de tecidos tumorais da próstata, foram obtidas IgY policlonais específicas que foram utilizadas no biopanning contra uma biblioteca de peptídeos recombinantes randômicos. Os fagos selecionados foram caracterizados por seqüenciamento e subsequentemente testados por dot immunoblotting e ELISA para validar a especificidade dos mesmos. Selecionou-se peptídeos que mimetizam proteínas prostáticas, possivelmente proteínas envolvidas no processo de tumorigênese. Esses peptídeos foram testados quanto a sua possível utilização no diagnóstico da resposta imune associada a processos tumorais. Neste trabalho, também foi desenvolvido com sucesso um imunossensor para diagnóstico que tem como base de detecção um sistema de cromatografia líquida por exclusão em micro colunas cromatográficas com bacteriófagos filamentosos carreadores de antígeno(s) e/ou anticorpo(s), selecionados por phage display, acoplados microesferas de látex coloridas, ativadas com diferentes grupamentos químicos. A presença do fago é de grande importância no processo, pois favorece a formação dos complexos antígeno-anticorpo, peptídeo-proteína ou peptídeo-substrato, ampliando a detecção ótica durante a separação por cromatografia ou por microaglutinação em microscopia ótica. A nova tecnologia pode também ser usada para a detecção de biomoléculas ou substâncias químicas associados a doenças infecciosas, parasitárias e genéticas, com rapidez, precisão, sensibilidade e reprodutibilidade, utilizando-se pequenos volumes de amostras e reagentes, apresentando praticidade e baixos custos. / Doutor em Genética e Bioquímica
138

Avaliação da expressão da proteína p53 e do VEGF (Fator de Crescimento do Endotélio Vascular) em pacientes com adenocarcinoma de esôfago / Evaluation of p53 protein and VEGF (vascular Endothelial Growth Factor) expresion in patients with esophageal adenocarcinoma

Cavazzola, Leandro Totti January 2004 (has links)
O prognóstico dos pacientes com adenocarcinoma de esôfago é bastante prejudicado pelo seu diagnóstico tardio. Na tentativa de determinar fatores que possam alterar o prognóstico destes pacientes, o estudo da biologia molecular tem recebido grande importância. As mutações no gene de supressão tumoral TP53 estão entre as anormalidades genéticas mais comuns encontradas numa ampla variedade de tumores. A angiogênese é essencial para o crescimento e a metastatização de tumores sólidos. O Fator de Crescimento do Endotélio Vascular (VEGF, Vascular Endothelial Growth Factor), um fator de crescimento identificado recentemente com propriedades angiogênicas significativas, pode ser um importante regulador desta angiogênese tumoral. A associação entre as expressões da proteína p53 e do VEGF e o prognóstico tem sido pouco estudada. Foram estudados 46 pacientes com adenocarcinoma de esôfago submetidos à cirurgia de ressecção com intenção curativa. As expressões da proteína p53 e do VEGF foram observadas por análise imuno-histoqímica em 52,2% e 47,8% dos tumores, respectivamente. As expressões da proteína p53 e do VEGF coincidiram em 26% dos casos, e não foi encontrada correlação entre essa expressão. Nenhum dos fatores clinicopatológicos se correlacionaram significativamente com as expressões da proteína p53 ou do VEGF. Não houve associação significativa entre as expressões da proteína p53 e do VEGF e sobrevida a longo prazo. No presente estudo, a expressão da proteína p53 e do VEGF, embora em porcentagem similar à da literatura, não se correlacionou com o prognóstico em pacientes com adenocarcinoma de esôfago submetidos à cirurgia com intenção curativa. / The prognosis of patients with esophageal adenocarcinoma is negatively influenced by late diagnosis. In an attempt to determine the factors that might improve the prognosis of these patients, molecular biology has been of great importance. P53 tumor suppressor gene mutations are one of the most frequent genetic disorders found in a wide variety of tumors. Angiogenesis is essential for the growth and metastatic spread of solid tumors. The Vascular Endothelial Growth Factor (VEGF), a recently identified factor with remarkable angiogenic properties, may play a central regulatory role in tumor angiogenesis. The association between p53 protein and VEGF expressions and prognosis has been underinvestigated. Forty-six patients with esophageal adenocarcinoma, submitted to curative resection, were studied. The expressions of p53 protein and VEGF were assessed by immunohistochemistry in 52.2% and 47.8% of tumors, respectively. P53 protein and VEGF expressions coincided in 26% of the cases, and no correlation between these expressions was observed. None of the clinicopathological factors showed a significant correlation with p53 protein or VEGF expressions. There was no significant association between p53 protein and VEGF expressions and long-term survival. In the present study, the expression of p53 protein and VEGF, albeit similar to the one reported in the literature, did not correlate with prognosis in esophageal adenocarcinoma patients submitted to curative resection.
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Expressão de marcadores de proliferação e apoptose em diferentes formas de carcinoma basocelular humano

Corrêa, Marília de Pádua Dornelas 14 December 2007 (has links)
Submitted by Renata Lopes (renatasil82@gmail.com) on 2016-10-31T11:38:11Z No. of bitstreams: 1 mariliadepaduadornelascorrea.pdf: 1683962 bytes, checksum: 535fc7956722559af7dce14b15336986 (MD5) / Approved for entry into archive by Adriana Oliveira (adriana.oliveira@ufjf.edu.br) on 2016-12-15T12:56:51Z (GMT) No. of bitstreams: 1 mariliadepaduadornelascorrea.pdf: 1683962 bytes, checksum: 535fc7956722559af7dce14b15336986 (MD5) / Made available in DSpace on 2016-12-15T12:56:51Z (GMT). No. of bitstreams: 1 mariliadepaduadornelascorrea.pdf: 1683962 bytes, checksum: 535fc7956722559af7dce14b15336986 (MD5) Previous issue date: 2007-12-14 / O Carcinoma basocelular (CBC) é o câncer mais comum em humanos, tendo predileção pela cabeça e pescoço, e sua incidência vem aumentando nos últimos anos. Estudos utilizando recursos da biologia molecular e genética, associados à histomorfologia, permitem a identificação de fatores de risco no desenvolvimento de lesões mais recorrentes e agressivas e propõem métodos mais eficazes de prevenção. O objetivo foi correlacionar a expressão dos marcadores de apoptose (p53 e Bcl-2) e proliferação celular (Ki-67 e PCNA) com os indicadores histológicos de gravidade do tumor. Foram estudadas cinco amostras de cada uma das formas nodular, morfeiforme e superficial e um grupo controle com três pacientes livres de lesão. O teste de Mann Whitney foi utilizado na comparação da expressão destes marcadores com a forma de apresentação do CBC. A marcação do Bcl-2 foi expressiva nos CBCs ditos agressivos. A variante morfeiforme foi a que mais o expressou, seguida pela nodular. Dos tumores estudados, 66,7% (dez) expressaram fortemente o p-53 e, nos controles, um indivíduo o expressou fracamente na camada basal. Nossos resultados mostram maior expressão do Ki-67 no CBC nodular e superficial, sem expressão nos controles. O PCNA mostrou forte marcação em todos os tipos de tumores e nos controles. O Bcl-2 e a p-53 apresentam tendência para diagnosticar gravidade do Carcinoma Basocelular, e o Ki-67, por seu comportamento variável, não pode ser considerado como marcador de gravidade, assim como o PCNA que não foi um bom marcador de proliferação celular. / Basal Cell Carcinoma (BCC) is the most common form of human cancer, showing a predilection for the head and neck region. Its incidence has been increasing over the last years. Studies employing resources from molecular and genetic medicine associated with histomorphology allow the identification of risk factors in the development of more recurring and aggressive lesions, and propose more efficient prevention methods. The objective was to correlate the expression of markers of apoptosis (p53 and bcl-2) and cell proliferation (Ki-67 and PCNA) with histological indicators of the gravity of the tumor. In this study we analyzed five samples of the nodular, sclerosing and superficial forms, respectively, and one control group with three lesion-free patients. The Mann-Whitney test was used to compare the expression of these markers with the form of manifestation of BCC. Bcl-2 expression was significant in the BCCs said to be aggressive. The sclerosing variant expressed it the most, followed by the nodular variant. Of the studied growths, 66.7% (10) expressed p-53 strongly. Among the controls, one individual expressed it weakly in the basal layer. Our results show a larger expression of Ki-67 in nodular and superficial BCCs, with no expression whatsoever in the controls. PCNA was strongly expressed in all types of tumors and in the controls. Bcl-2 and p-53 have a tendency to indicate the gravity of Basal Cell Carcinoma. In contrast, Ki-67, due to its variable behaviour, can not be considered to be a marker of gravity. Furthermore, OCNA was not a good marker of cell proliferation.
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"Predição do risco de metástase do carcinoma bem diferenciado da glândula tireóide pela quantificação digital da imunoexpressão da galectina-3 nos compartimentos do tireócito maligno" / Prediction of metastasis risk in well-differentiated thyroid carcinoma based on digital quantification of galectin-3 immunoexpression in subcellular compartments of the malignant thyrocyte

Elaine Stabenow 21 August 2006 (has links)
INTRODUÇÃO: Os carcinomas papilífero e folicular são neoplasias malignas primárias da glândula tireóide. Em conjunto, recebem o nome de carcinoma bem diferenciado. Determinar o risco individual da ocorrência de metástase nesses casos auxilia na seleção da terapêutica que é atualmente baseada na classificação de acordo com fatores prognósticos, aos quais pode ser associada a pesquisa de marcadores biológicos. Dentre eles, destaca-se a galectina-3, cujas funções exercidas nos compartimentos celulares foram descritas em uma variedade de neoplasias. Entretanto, seu papel no carcinoma tireóideo permanece controverso. Com o intuito de investigar se a galectina-3 pode auxiliar na predição do risco individual da ocorrência de metástase e se está associada aos critérios de malignidade do carcinoma bem diferenciado, a presente pesquisa objetivou verificar as seguintes hipóteses: 1) se há diferença da imunoexpressão da galectina-3 nos compartimentos do tireócito maligno entre os doentes com e sem metástase e se é possível predizer o risco de metástase em função da quantificação digital desse marcador; 2) se há diferença da imunoexpressão da galectina-3 entre o tecido tireóideo maligno e o não neoplásico; conforme a presença de invasão tecidual; e conforme a sobrevivência; 3) se há indício do envolvimento da galectina-3 com apoptose, indução da proliferação celular e angiogênese. MÉTODO: Trata-se de estudo retrospectivo de caso-controle que envolveu 109 doentes operados por carcinoma bem diferenciado da tireóide e seguidos por mais de cinco anos, distribuídos em dois grupos equivalentes: com e sem metástase. Foram feitos coleta de dados clínicos, avaliação anátomo-patológica e análise imunohistoquímica digital dos biomarcadores galectina-3, Ki-67, caspase-3 e CD-34. RESULTADOS: 1) A média do índice de positividade nucleolar da galectina-3 foi maior no grupo de doentes com metástase linfática cervical (1,78 ± 0,41 nucléolos/CGA contra 0,35 ± 0,13, p=0,004). A expressão nucleolar da galectina-3 apresentou especificidade de 75% para identificação da ocorrência de metástase e foi fator independente associado à ocorrência metástase linfática (p=0,01). A equação logística obtida permitiu calcular o risco individual de desenvolvimento de metástase linfática cervical que é próximo a 100% quando a galectina-3 está imunoexpressa em quatro ou mais nucléolos por campo microscópico de grande aumento. 2) não houve expressão da galectina-3 no tireócito não neoplásico; o índice de expressão citoplasmático foi fator independente associado à presença de invasão linfática (p=0,013) e a média desse índice foi maior nos casos com extensão extratireóidea (52,7 ± 3,9 uo/µm2 contra 41,0 ± 4,0, p=0,037); não houve associação dos índices de imunoexpressão da galectina-3 e sobrevivência; 3) no grupo de doentes com metástase, a expressão nucleoplasmática da galectina-3 correlacionou-se de forma positiva com o índice de positividade do Ki-67 e, nos dois grupos, a expressão citoplasmática com o índice de expressão da caspase-3. CONCLUSÕES: Foi possível predizer o risco individual da ocorrência de metástase linfática cervical em função da quantificação digital da imunoexpressão nucleolar da galectina-3. O presente estudo sugere que alta expressão citoplasmática está associada com algumas características de invasão local. Houve indícios do envolvimento da galectina-3 com indução da proliferação celular e apoptose no grupo de doentes com metástase. / INTRODUCTON: Papillary and follicular carcinomas are primary malignant neoplasias of the thyroid gland and are classified as well-differentiated carcinoma. In these cases, determination of individual risk of metastasis allows offering an adequate treatment. Nowadays therapy is chosen based on classification according to prognostic factors and biomarkers can be associated with them. Galectin-3 is one of these markers and has been thoroughly studied. A wide range of functions that it carries out in the subcellular compartments have been described in several neoplasms. However, its role in thyroid carcinomas remains controversial. In order to investigate if galectin-3 can be used to predict the individual risk of metastasis and if this marker is associated with malignant criteria of well-differentiated carcinoma, this study was proposed to verify the following hypotheses: 1) if galectin-3 immunostaining in subcellular compartments of the malignant thyrocyte is different when comparing patients with and without metastasis and if it is possible to predict the individual risk of metastasis based on digital quantification of the galectin-3 immunostaining; 2) if galectin-3 immunoexpression is different from malignant and benign thyroid tissue; according to tissue invasion and survival; 3) if there are indications that galectin-3 plays a role in apoptosis and cell proliferation or angiogenesis induction. METHODS: It was performed a retrospective case-control study involving 109 patients treated for well-differentiated thyroid carcinoma and followed up for more than five years. They were divided into two equivalent groups: with and without metastasis. The search of clinical data, morphological evaluation and digital immunohistochemical analysis with galectin-3, Ki-67, caspase-3 and CD-34 antibodies were done. RESULTS: 1) the average of the nucleolar galectin-3 positive index was higher in lymph node metastasis group (1.78 ± 0.41 nucleoli/HPF versus 0.35 ± 0.13, P=.004). Nucleolar staining was an independent factor associated with lymph node metastasis (P=.01) and its specificity to identify metastasis was 75%. The logistic model allowed predicting the individual risk of cervical lymph node metastasis. It was almost 100% for carcinomas displaying more than four galectin-3 immunostained nucleoli by microscopic high power field. 2) There was no galectin-3 immunostaining in non-neoplasic thyrocyte; the cytoplasmic galectin-3 expression index was an independent factor associated with lymphatic invasion (P=.013) and these index average was higher in cases with extrathyroidal extension (52.7 ± 3.9 uo/µm2 versus 41.0 ± 4.0, P=.037); there was no association of galectin-3 immunostaining indexes with survival; 3) in the metastasis group, there was positive correlation between nucleoplasmic staining of galectin-3 and Ki-67 positive index; there was positive correlation between cytoplasmic staining of galectin-3 and caspase-3 positive index in both groups. CONCLUSION: It was possible to predict the individual risk of cervical lymph node metastasis based on digital quantification of the nucleolar galectin-3 immunostaining. This study suggests that there is association of high cytoplasmic expression with local tissue invasion. In the metastasis group there were indications that galectin-3 plays a role in cell proliferation and apoptosis induction.

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