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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.
41

Avaliação da influência da expressão de STAT1 na resposta ao tratamento quimioterápico no cancêr de ovário seroso de alto grau / Influence of STAT1 expression in response to chemotherapy in highgrade serous ovarian cancer

Josahkian, Juliana Alves 07 June 2016 (has links)
O câncer de ovário é uma importante causa de mortalidade. O subtipo seroso de alto grau é o mais frequente e caracteriza-se por comportamento agressivo, com crescimento rápido e metástase precoce. A falta de ferramentas para diagnóstico em estádios iniciais e a insuficiência de resposta à quimioterapia convencional são dois principais obstáculos para o manejo do câncer seroso de ovário. A detecção precoce neste tumor é complicada por sintomas inespecíficos e ausência de biomarcadores confiáveis. Além disso, o desenvolvimento de resistência à quimioterapia é um desafio para o tratamento, que é geralmente baseado na combinação de platina e paclitaxel. A influência do microambiente tumoral na resposta terapêutica ainda é pouco conhecida. No entanto, há evidências crescentes de que a resposta imunológica pré-existente pode estar relacionada com a variação da sensibilidade à quimioterapia. O microambiente imunorreativo foi associado à melhor prognóstico no câncer do ovário seroso de alto grau em recente estudo canadense. Proteínas da família de Transdutores de Sinal e Ativadores da Transcrição (STATs) participam da regulação de citocinas e são determinantes nas respostas imunes no microambiente tumoral, podendo promover ou inibir o crescimento tumoral. Dados recentes mostram que a expressão elevada de um dos reguladores de STAT, STAT1 atua na tumorigênese do câncer de ovário, facilitando a resposta imune e, potencialmente, alterando a resposta à quimioterapia. Para avaliar o papel da expressão de STAT1 como biomarcador preditivo em 65 pacientes brasileiras com câncer seroso de ovário, examinamos os níveis de STAT1 por imunoistoquímica, e analisamos se houve correlação entre expressão dessa proteína e resposta clínica. Alta expressão de STAT1 foi significativamente associada maior intervalo livre de doença (P=0,0256) e maior sobrevida global (P=0,0193). Estes achados da coorte brasileira, com tempo de seguimento maior que cinco anos, confirmam a associação entre alta expressão de STAT1 e melhor resposta à quimioterapia, e fornecem validação adicional desta proteína como um biomarcador preditivo. Além disso, estes resultados chamam atenção para a possibilidade de utilizar a via de STAT1 para o desenvolvimento de novos medicamentos imunomoduladores, que poderiam melhorar a resposta ao tratamento / Ovarian cancer is a major cause of mortality worldwide. The most frequent subtype is high grade serous, which is characterized by aggressive behavior with rapid growth and early metastasis. Lack of early diagnostic tools and failure of response to conventional chemotherapies are two major impediments to serous ovarian cancer management. Early detection in initial stages is complicated by non-specific symptoms and lack of reliable biomarkers. In addition, development of chemotherapy resistance is a challenge for treatment, which is generally based on combination of platinum and paclitaxel. The influence of the microenvironment of the tumor on therapeutic response is still unknown. However, there is increasing evidence that a pre-existing immunological response may be related to variation in chemotherapy sensitivity. The immunoreactive microenvironment has been shown to be associated with better prognosis in high grade serous ovarian cancer in a recent Canadian study. The Signal Transducer and Activator of Transcription (STAT) proteins regulate cytokines and are central in determining whether immune responses in the tumor microenvironment promote or inhibit cancer. Recent data show that high expression of one of the STAT regulators, STAT1, operates in ovarian cancer tumorigenesis, facilitating immune response and potentially altering response to chemotherapy. To evaluate the role of STAT1 expression as a predictive biomarker in 65 Brazilian serous ovarian cancer patients, we examined STAT1 levels by immunohistochemistry to determine if there was correlation between expression of this protein and clinical response. High expression of STAT1 was significantly associated with both improved disease-free survival (P=0,0256) and overall survival (P=0,0193). These findings from a Brazilian cohort after more than five years of follow up confirm the association of high STAT1 expression with better response to chemotherapy, and provide additional validation of this protein as a predictive biomarker. Moreover these results draw attention to the possibility of utilizing the STAT1 pathway for the development new immunomodulator drugs, that could enhance response to treatment
42

Desempenho dos imunomarcadores MCM2, bcl2 e Vilina no diagnóstico diferencial de adenocarcinomas endocervicais e endometriais

Cysneiros, Maria Auxiliadora de Paula Carneiro 16 October 2013 (has links)
Submitted by Luciana Ferreira (lucgeral@gmail.com) on 2014-09-24T14:56:36Z No. of bitstreams: 2 Cysneiros, Maria Auxiliadora de Paula Carneiro.pdf: 1396665 bytes, checksum: f26660692713226fc47ed6704e9d53a9 (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) / Approved for entry into archive by Cláudia Bueno (claudiamoura18@gmail.com) on 2014-09-28T02:03:10Z (GMT) No. of bitstreams: 2 Cysneiros, Maria Auxiliadora de Paula Carneiro.pdf: 1396665 bytes, checksum: f26660692713226fc47ed6704e9d53a9 (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) / Made available in DSpace on 2014-09-28T02:03:10Z (GMT). No. of bitstreams: 2 Cysneiros, Maria Auxiliadora de Paula Carneiro.pdf: 1396665 bytes, checksum: f26660692713226fc47ed6704e9d53a9 (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) Previous issue date: 2013-10-16 / Endocervical and Endometrial Adenocarcinomas are uterine neoplasms with different biological behaviors and different treatments, being all the therapeutic plan based on the origin site of these tumors. To differentiate these two neoplasms, many times the immunohistochemical study is used as an ancillary tool to assist and complement histopathological examination. Previous studies have investigated the value of various markers in the distinction of these neoplasms, with results varying and sometimes conflicting. In this study the impact of the MCM2, bcl2 and villin markers in the differential diagnosis of endocervical and endometrial adenocarcinomas, associated or not to a traditional markers panel formed by CEA, vimentin, RE, RP and p16, was evaluated. Material and methods: A tissue microarray (TMA) was constructed using paraffin-embedded, formalin-fixed tissues from 104 hysterectomy specimens and conizations. Out of the 104, 51 samples were represented by unequivocal cases of adenocarcinomas of the endocervice and 53 represented unequivocal cases of endometrial adenocarcinomas. The sections of tissue microarray block were immunostained with the eight antibodies in study and to the antigen-antibody reaction preview it was used the polymer detection system. Scoring of immunostaining was interpreted using the German semi quantitative scoring system in considering the staining intensity and area extent of marker expression. The final Immunoreactive score was determined by multiplying the positive intensity and the positive area extent scores. The threshold for differentiating between final positive and negative immunostaining was set at 4 for interpretation (0-3 = negative; 4-12 = positive). Results: The univariate analysis showed that out of the eight markers, seven (CEA, vimentin, RE, RP, p16, MCM2 and bcl2) showed good performance in the distinction between the endocervical and endometrial origin. The multivariate analysis showed that CEA, p16 and MCM2 were the strongest predictors of site of origin. In the evaluation of six panels built by various combinations of immunomarkers , the panel with the lowest accuracy was that represented by MCM2, bcl2 and villin. The villin did not show any statistically significant difference in the differential diagnosis of these adenocarcinomas. Despite the MCM2 and bcl2 have revealed significant differences of frequency between the two sites of origin, they did not demonstrate additional benefit when added to a traditional panel. Conclusion: According to our study, the inclusion of MCM2, bcl2 and villin in the immunohistochemical assessment of uterine adenocarcinomas, added no supplementary value in the differentiation of these two neoplasms. / Adenocarcinomas endocervicais e endometriais são neoplasias uterinas com comportamentos biológicos e tratamentos distintos, sendo todo o plano terapêutico baseado no sítio de origem desses tumores. Para diferenciação dessas duas neoplasias, muitas vezes utiliza-se o estudo imuno-histoquímico como ferramenta auxiliar e complementar ao exame histopatológico. Prévios estudos têm investigado o valor de diferentes marcadores na distinção dessas neoplasias, com resultados variáveis e, por vezes, conflitantes. Neste estudo foi avaliado o desempenho dos marcadores MCM2, bcl2 e vilina no diagnóstico diferencial desses adenocarcinomas, associados ou não a um painel de marcadores tradicionais formados por CEA, vimentina, RE, RP e p16. Material e métodos: Um microarranjo de tecido (TMA) foi construído usando tecidos fixados em formol e embebidos em parafina, a partir de 104 amostras provenientes de histerectomias e conizações. Das 104 amostras, 51 eram representadas por casos inequívocos de adenocarcinomas de endocérvice e 53 representavam casos inequívocos de adenocarcinomas de endométrio. As secções do bloco de TMA foram imunomarcadas com os oito anticorpos em estudo e para vizualização da reação antígeno-anticorpo foi utilizado o sistema de detecção com polímeros. A marcação imuno-histoquímica foi graduada de acordo com o sistema semi-quantitativo alemão, levando-se em consideração a intensidade de marcação e a extensão de células marcadas. O score de imunorreatividade final foi determinado pela multiplicação da intensidade pela extensão de marcação. Um limite de corte de 4 foi determinado para diferenciação entre um resultado final positivo ou negativo (0- 3= negativo; 4- 12= positivo). Resultados: Análise univariada mostrou que dos oito marcadores avaliados, sete (CEA, vimentina, RE, RP, p16, MCM2 e bcl2) apresentaram bom desempenho na distinção entre origens endocervical e endometrial da neoplasia. Análise multivariada mostrou que CEA, p16 e MCM2 foram os mais fortes preditores do sítio anatômico. Na avaliação dos seis painéis construídos por combinações variadas desses marcadores, o painel com menor acurácia diagnóstica foi o representado por MCM2, bcl2 e vilina. A vilina não apresentou nenhuma diferença estatisticamente significativa no diagnóstico diferencial desses adenocarcinomas. Apesar do MCM2 e bcl2 terem revelado diferenças significativas de frequência entre os dois sítios de origem, eles não demonstraram valor suplementar quando adicionados a um painel tradicional. Conclusão: De acordo com este estudo, a inclusão de MCM2, bcl2 e vilina em um painel tradicional de 5 marcadores (CEA, vimentina, RE, RP, p16), não agregou nenhum benefício adicional na distinção imuno-histoquímica do sítio de origem desses adenocarcinomas uterinos.
43

The identification of novel biomarkers in the development and progression of early prostate cancer

Rasiah, Krishan Kumar, St Vincent's, UNSW January 2006 (has links)
ABSTRACT The morphological premalignant changes in prostate epithelium such as high grade prostatic intraepithelial neoplasia (HGPIN) precede invasive prostate cancer (PC) by several decades. The overall aim of this project was to identify patterns of gene expression in HGPIN and early PC which increase our understanding of the early biology of PC and identify genes and pathways that correlate with an aggressive phenotype. A comprehensive tissue cohort of premalignant prostate lesions was collected in a tissue microarray (TMA) platform that was utilised for high-throughput validation of target genes. Using this unique resource, the expression of the tumour suppressor gene PTEN was assessed using immunohistochemistry in an initial candidate gene approach based on mouse models implicating PTEN in carcinogenesis. No significant difference in expression of PTEN was detected in premalignant and benign epithelium. A transcript profiling approach was undertaken by integrating laser capture microdissection, linear RNA amplification and oligonucleotide microarrays to perform a screen of matched patient samples of normal, HGPIN and PC cells. The expression patterns of two genes encoding secreted proteins, neuropeptide Y (NPY) and macrophage inhibitory cytokine (MIC-1) were validated using immunohistochemistry on TMAs representing the progression model of early PC. Increased expression of these proteins in PC was confirmed to occur early in the disease process and altered expression of NPY and MIC-1 was associated with worse clinical outcome. Further analysis of global gene expression patterns using a structured network knowledge base identified a notable aberration in the expression of extracellular matrix and extracellular matrix associated proteins in HGPIN and provided novel evidence for the role of this class of molecules in the development of PC. In summary, contrary to current dogma based on work in animal models, altered PTEN expression is unlikely to represent an important event in the development of malignancy in the human prostate. In contrast, the expression patterns and prognostic value of NPY and MIC-1 in HGPIN support their further evaluation as biomarkers for the development and progression of PC. The aberrant expression of genes and networks of genes detected in HGPIN will assist in further identification of biological pathways which may be targeted in therapeutic strategies against the development and progression of PC.
44

Hypoxia inducible factor-1α in renal cell carcinoma

Lidgren, Anders January 2007 (has links)
Hypoxia Inducible Factor-1α in Renal Cell Carcinoma Departments of Surgical and Perioperative Sciences, Urology and Andrology; Radiation Sciences, Oncology; Medical Biosciences, Pathology; and Medical Biosciences, Clinical Chemistry, Umeå University, Umeå, Sweden Background: Renal cell carcinoma (RCC) accounts for approximately 2-3% of all human cancers. A distinguished feature of RCC is vascularisation and among the three dominating RCC types conventional RCC (cRCC) generally is more vascularised than papillary RCC (pRCC) and chromophobe RCC (chRCC). Angiogenesis is a critical step in tumour progression controlled by a balance involving molecules that have positive and negative regulatory activity. A balance distorted by metabolic stress such as hypoxia, acidosis, and inflammation. Hypoxia-Inducible Factor 1α (HIF-1α) is a key transcription factor in angiogenesis and tumour progression, targeting more than a 100 genes involved in vascular growth and regulation, iron metabolism and erythropoesis, collagen matrix formation, regulation of extracellular pH, glucose uptake and metabolism, proliferation, apoptosis, differentiation, and cell viability. Methods: Tumour tissue and corresponding kidney cortex from nephrectomised RCC patients was used in order to characterize HIF-1α expression and one of its target genes, Glucose Transporter 1 (GLUT-1). All tumour samples were thoroughly described regarding tumour type, TNM stage, nuclear grade, tumour size, vein invasion, and patient survival. Utilizing RT-PCR, Westen Blot and Tissue micro array (TMA) we studied HIF-1α mRNA and protein expression as well as GLUT-1 protein expression, correlating them to each other and clinicopathological parameters. Results: Using Western Blot, HIF-1α protein expression differed significantly between the different RCC types and kidney cortex. In cRCC, high expression of HIF-1α was an independent prognostic factor for favourable prognosis. TMA is a useful method to analyze HIF-1α protein expression in RCC. HIF-1α levels were significantly lower in locally aggressive cRCC and patients with high levels of HIF-1 tended to have a better prognosis. GLUT-1 levels were higher in cRCC than in other RCC types and for cRCC a correlation to HIF-1α was seen. HIF-1α mRNA levels were significantly lower in cRCC compared to other RCC types and kidney cortex. An inverse correlation between HIF-1α protein expression and mRNA levels was observed. Summary: These results demonstrate a discrepancy between RCC types, highlighting the need to separately evaluate biological events in different RCC types. Overexpression of HIF-1α protein is not necessarily all bad and translational regulation appears more critical than anticipated. Further studies are encouraged to clarify angiogenic pathways in RCC.
45

Angiogenesis in human renal cell carcinoma : hypoxia, vascularity and prognosis

Sandlund, Johanna January 2007 (has links)
Background: Angiogenesis is recognised as a critical step in tumour progression. The angiogenic switch is activated by various trigger signals, such as hypoxia, low pH, and genetic mutations. Renal cell carcinoma (RCC) is often an aggressive tumour, and advanced disease has limited treatment options and bad prognosis. This study was focused on markers of angiogenesis in RCC: endoglin (CD105) and CD31 assessing microvessel density (MVD), and carbonic anhydrase (CA) IX and hypoxia-inducible factor (HIF)-2α expressed at hypoxia. Upregulation of HIF is also associated with inactivation of the von Hippel-Lindau (VHL) tumour suppressor gene, which is common in conventional/clear cell (c)RCC. Method: A tumour bank containing 308 tumours from patients operated 1982-2003 was used. The tumours were well characterised regarding tumour type, TNM stage, nuclear grade, tumour size, and patient survival. The tumours were prepared in tissue microarrays and fresh frozen in whole sections. To analyse the expression of endoglin, CD31, CA IX, and HIF-2α mRNA, immunohistochemistry and real-time PCR were used. Results: There was a higher endoglin expression in cRCC than in papillary (p)RCC and chromophobe (ch)RCC, and a higher CD31 expression in cRCC than in pRCC. MVD correlated inversely to TNM stage and nuclear grade in cRCC. There was also an inverse correlation between tumour diameter and CD31 expression in cRCCs. Patients with cRCC with high MVD had a more favourable prognosis than patients with lower MVD. Endoglin and CD31 were not independent prognostic factors. The CA IX expression was higher in cRCC than in pRCC and chRCC. Patients with cRCC expressing low CA IX had a significantly less favourable prognosis compared with those with higher expression. CA IX is an independent prognostic factor. There was a higher HIF-2α mRNA expression in cRCC than in pRCC and chRCC. In cRCC, there was a significant inverse correlation between HIF-2α mRNA expression, and TNM stage and nuclear grade. There was also an inverse correlation between HIF-2α mRNA expression and tumour size among patients with cRCC. HIF-2α was not an independent prognostic factor. Conclusion: In these studies, the factors related to hypoxia and vascularity were all inversely correlated to tumour aggressiveness in cRCC. MVD, CA IX, and HIF-2α expression were also higher in cRCC than in pRCC and chRCC. The relationship between angiogenesis, vascularity, and hypoxia is ambiguous. A line of reasoning including mutations increasing angiogenesis in advanced disease may also be applied to RCC. Measurements of individual angiogenic factors seem to provide prognostic information, and can potentially be combined in patient monitoring and treatment.
46

Biomarker Discovery in Cutaneous Malignant Melanoma : A Study Based on Tissue Microarrays and Immunohistochemistry

Agnarsdóttir, Margrét January 2011 (has links)
The incidence of cutaneous malignant melanoma has increased dramatically in Caucasians the last few decades, an increase that is partly explained by altered sun exposure habits. For the individual patient, with a localized disease, the tumor thickness of the excised lesion is the most important prognostic factor. However, there is a need to identify characteristics that can place patients in certain risk groups. In this study, the protein expression of multiple proteins in malignant melanoma tumors was studied, with the aim of identifying potential new candidate biomarkers. Representative samples from melanoma tissues were assembled in a tissue microarray format and protein expression was detected using immunohistochemistry. Multiple cohorts were used and for a subset of proteins the expression was also analyzed in melanocytes in normal skin and in benign nevi. The immunohistochemical staining was evaluated manually and for part of the proteins also with an automated algorithm. The protein expression of STX7 was described for the first time in tumors of the melanocytic lineage. Stronger expression of STX7 and SOX10 was seen in superficial spreading melanomas compared with nodular malignant melanomas. An inverse relationship between STX7 expression and T-stage was seen and between SOX10 expression and T-stage and Ki-67, respectively. In a population-based cohort the expression of MITF was analyzed and found to be associated with prognosis. Twenty-one potential biomarkers were analyzed using bioinformatics tools and a protein signature was identified which had a prognostic value independent of T-stage. The protein driving this signature was RBM3, a protein not previously described in malignant melanoma. Other markers included in the signature were MITF, SOX10 and Ki-67. In conclusion, the protein expression of numerous potential biomarkers was extensively studied and a new prognostic protein panel was identified which can be of value for risk stratification.
47

Caractérisation du potentiel métastatique des carcinomes mammaires de phénotype basal

Grosset, Andrée-Anne 08 1900 (has links)
Au Canada, on estime qu'une femme sur neuf développera un cancer du sein et qu'une femme sur vingt-huit en mourra. Les carcinomes mammaires de phénotype basal qui comprennent environ 15 à 25% des cancers envahissants du sein sont des tumeurs malignes ayant un très mauvais pronostic. Dans ce type tumoral, les métastases sont fréquentes et les décès nombreux. La formation des métastases est un processus complexe qui comprend plusieurs étapes; chacune peut être étudiée par des marqueurs spécifiques. Notre hypothèse de recherche est que le carcinome mammaire de phénotype basal possède des caractéristiques spécifiques qui permettent d'expliquer son potentiel métastatique élevé. Six micromatrices tissulaires comprenant un total de 213 tumeurs mammaires ont été confectionnées. L'expression des marqueurs usuels de la métastase et celle de nouveaux marqueurs a été étudiée par des techniques d'immunohistochimie. L'étude comparative de l’expression des marqueurs du potentiel métastatique par les carcinomes mammaires de phénotype basal indique que les protéines Ki-67, EGFR, CD276 et galectine-7 sont étroitement reliées à ce type de cancer. De plus, l'expression du marqueur GATA-3, un marqueur anti-métastatique, fait complètement défaut. Nos résultats confirment que le cancer du sein de phénotype basal possède un plus grand potentiel métastatique que les autres sous-types génétiques et suggèrent que la galectine-7 puisse être impliquée. / In Canada, we estimate that one woman in nine will develop a breast cancer, and one woman in twenty-eight will succumb of her disease. The basal-like breast cancer which represents 15 to 25% of invasive breast cancer, is associated with a poor prognosis. Metastases are the main cause of mortality for patients affected from cancer. Many steps are involved in the metastatic cascade. Each step can be studied using specific markers. Our research hypothesis is that basal-like breast cancer have distinct charactheristics which can explain their higher metastatic potential and poor overall survival. Six tissue microarrays comprising a total of 213 breast tumors were assembled. The relative expression of conventional and putative metastasis related markers was studied using immunohistochemistry. When the expression of metastatic potential markers was evaluated in breast carcinomas, basal-like breast cancer was found to express higher levels of Ki-67, EGFR, CD276 and galectin-7. Furthermore, GATA-3, an antimetastatic protein, was found to be completely absent in basal-cell type breast cancers. Our results confirm that the basal-like breast cancer has a highest metastatic potential than the other molecular subtypes and suggest that galectin-7 may play a role.
48

The identification of novel biomarkers in the development and progression of early prostate cancer

Rasiah, Krishan Kumar, St Vincent's, UNSW January 2006 (has links)
ABSTRACT The morphological premalignant changes in prostate epithelium such as high grade prostatic intraepithelial neoplasia (HGPIN) precede invasive prostate cancer (PC) by several decades. The overall aim of this project was to identify patterns of gene expression in HGPIN and early PC which increase our understanding of the early biology of PC and identify genes and pathways that correlate with an aggressive phenotype. A comprehensive tissue cohort of premalignant prostate lesions was collected in a tissue microarray (TMA) platform that was utilised for high-throughput validation of target genes. Using this unique resource, the expression of the tumour suppressor gene PTEN was assessed using immunohistochemistry in an initial candidate gene approach based on mouse models implicating PTEN in carcinogenesis. No significant difference in expression of PTEN was detected in premalignant and benign epithelium. A transcript profiling approach was undertaken by integrating laser capture microdissection, linear RNA amplification and oligonucleotide microarrays to perform a screen of matched patient samples of normal, HGPIN and PC cells. The expression patterns of two genes encoding secreted proteins, neuropeptide Y (NPY) and macrophage inhibitory cytokine (MIC-1) were validated using immunohistochemistry on TMAs representing the progression model of early PC. Increased expression of these proteins in PC was confirmed to occur early in the disease process and altered expression of NPY and MIC-1 was associated with worse clinical outcome. Further analysis of global gene expression patterns using a structured network knowledge base identified a notable aberration in the expression of extracellular matrix and extracellular matrix associated proteins in HGPIN and provided novel evidence for the role of this class of molecules in the development of PC. In summary, contrary to current dogma based on work in animal models, altered PTEN expression is unlikely to represent an important event in the development of malignancy in the human prostate. In contrast, the expression patterns and prognostic value of NPY and MIC-1 in HGPIN support their further evaluation as biomarkers for the development and progression of PC. The aberrant expression of genes and networks of genes detected in HGPIN will assist in further identification of biological pathways which may be targeted in therapeutic strategies against the development and progression of PC.
49

The identification of novel biomarkers in the development and progression of early prostate cancer

Rasiah, Krishan Kumar, St Vincent's, UNSW January 2006 (has links)
ABSTRACT The morphological premalignant changes in prostate epithelium such as high grade prostatic intraepithelial neoplasia (HGPIN) precede invasive prostate cancer (PC) by several decades. The overall aim of this project was to identify patterns of gene expression in HGPIN and early PC which increase our understanding of the early biology of PC and identify genes and pathways that correlate with an aggressive phenotype. A comprehensive tissue cohort of premalignant prostate lesions was collected in a tissue microarray (TMA) platform that was utilised for high-throughput validation of target genes. Using this unique resource, the expression of the tumour suppressor gene PTEN was assessed using immunohistochemistry in an initial candidate gene approach based on mouse models implicating PTEN in carcinogenesis. No significant difference in expression of PTEN was detected in premalignant and benign epithelium. A transcript profiling approach was undertaken by integrating laser capture microdissection, linear RNA amplification and oligonucleotide microarrays to perform a screen of matched patient samples of normal, HGPIN and PC cells. The expression patterns of two genes encoding secreted proteins, neuropeptide Y (NPY) and macrophage inhibitory cytokine (MIC-1) were validated using immunohistochemistry on TMAs representing the progression model of early PC. Increased expression of these proteins in PC was confirmed to occur early in the disease process and altered expression of NPY and MIC-1 was associated with worse clinical outcome. Further analysis of global gene expression patterns using a structured network knowledge base identified a notable aberration in the expression of extracellular matrix and extracellular matrix associated proteins in HGPIN and provided novel evidence for the role of this class of molecules in the development of PC. In summary, contrary to current dogma based on work in animal models, altered PTEN expression is unlikely to represent an important event in the development of malignancy in the human prostate. In contrast, the expression patterns and prognostic value of NPY and MIC-1 in HGPIN support their further evaluation as biomarkers for the development and progression of PC. The aberrant expression of genes and networks of genes detected in HGPIN will assist in further identification of biological pathways which may be targeted in therapeutic strategies against the development and progression of PC.
50

Estudo da correla??o das caracter?sticas cl?nico-patol?gicas do c?ncer colorretal com a express?o imunohistoqu?mica de prote?nas da progress?o tumoral

Lira, George Alexandre 31 August 2015 (has links)
Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2016-06-03T23:19:48Z No. of bitstreams: 1 GeorgeAlexandreLira_DISSERT.pdf: 12487121 bytes, checksum: e5befba62b31cf9c0849235dd847b32c (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2016-06-06T23:43:09Z (GMT) No. of bitstreams: 1 GeorgeAlexandreLira_DISSERT.pdf: 12487121 bytes, checksum: e5befba62b31cf9c0849235dd847b32c (MD5) / Made available in DSpace on 2016-06-06T23:43:09Z (GMT). No. of bitstreams: 1 GeorgeAlexandreLira_DISSERT.pdf: 12487121 bytes, checksum: e5befba62b31cf9c0849235dd847b32c (MD5) Previous issue date: 2015-08-31 / Excluindo-se os tumores de pele n?o-melanoma, o c?ncer colorretal ? o segundo mais comum no sudeste do Brasil; o terceiro na regi?o sul e na regi?o Centro-Oeste. J? no norte do Brasil, ? o quarto e, na regi?o Nordeste, o quinto. Avaliar vari?veis clinico-patol?gicos do c?ncer colorretal ? de fundamental import?ncia para se conhecer poss?veis desfechos na sobrevida dos pacientes portadores e pontuar caracter?sticas na progress?o tumoral como o perfil da invas?o tumoral e angiog?nese. O objetivo desse trabalho ? estudar as caracter?sticas cl?nico-patol?gicas dos pacientes portadores do c?ncer colorretal (CCR) na Liga Norte Riograndense contra o c?ncer em Natal-RN/BR, analisando as vari?veis cl?nicas e patol?gicas como par?metros de progn?stico e determinando o n?vel de express?o de prote?nas, tais sejam: E-caderina (E-cad), Beta-catenina (?-cat), Galectina-3 (Gal-3), Metaloproteinases de matriz (MMP) 2 e 9 e o Fator alfa de crescimento v?sculo-endotelial (VEGF-?) nos tecidos tumorais. Foi realizado um estudo retrospectivo dos casos de c?ncer colorretal da Liga Norte-Riograndense contra o C?ncer no per?odo de 1995 a 2005 em Natal-RN / Brasil. As vari?veis cl?nico-patol?gicas, tais como: idade, sexo, etnia, h?bitos de vida, hist?ria familiar, local do tumor prim?rio, grau de diferencia??o, estadiamento TNM, Dukes? modificado, tratamento e sobrevida foram analisadas. Os dados cl?nico-patol?gicos foram coletados dos prontu?rios m?dicos atrav?s de um formul?rio espec?fico e os dados foram armazenados em uma planilha do Excel. Um total de 534 pacientes foi selecionado do arquivo do setor da patologia dessa institui??o, mas 176 pacientes foram exclu?dos. 358 pacientes foram inclu?dos para an?lise epidemiol?gica e suas correla??es cl?nico-patol?gicas foram realizadas. 180 pacientes foram selecionados para estudos histol?gicos e imunohistoqu?micos. Prote?nas participantes da progress?o tumoral E-caderina, Beta-catenina, Galectina-3, Metaloproteinases 2 e 9 e o Fator alfa de crescimento endotelial vascular foram analisadas. Os blocos de parafina dessas amostras foram tratados pela t?cnica de Tissue Microarray e suas l?minas submetidas a imunohistoqu?mica para avaliar a intensidade de marca??o dessas prote?nas nos tecidos tumorais. Os resultados dessa an?lise foram correlacionados ?s vari?veis cl?nico-patol?gicas dos pacientes. An?lise estat?stica pelo Teste de qui-quadro de Pearson e an?lise de sobrevida pela Curva de Kaplan-Meier foram utilizados. Valores de p<0,05 foram considerados estatisticamente significativos. A m?dia de idade da nossa amostra foi de 58,8 anos e 51,7% foram do sexo feminino. O consumo de ?lcool aumentou em 1,71 vezes o risco de morte pelo CCR (p=0,034). J? o tabaco aumentou 2,7 vezes a chance de desenvolver tumores de alto est?gio TNM (p=0,001). Os pacientes com hist?rico familiar de c?ncer teve 3,833 vezes a chance de desenvolver o CCR (p=0,002). A express?o da MMP-2 mostrou uma associa??o significativa com os tumores de alto est?gio TNM (p<0,046) e mortalidade (p=0,041). A express?o do ? VEGF teve correla??o estatisticamente significante com o alto est?gio TNM (p<0,009), grau de indiferencia??o celular (p<0,025) e mortalidade (p<0,035). As express?es da E-caderina e Beta-catetina mostraram associa??o do tumor com alto est?gio TNM (p=0,0001) e Dukes? modificado (p=0,05), les?o em reto (p=0,03 e p=0,007, respectivamente), tabaco (p=0,05) e indiferencia??o (p=0,001). A express?o das Gal-3 apresentou relev?ncia estat?stica com pacientes de alto est?gio TNM (p=0,01), fumantes (p=0,01), etilista (p=0,03), indiferencia??o (p=0,0001) e mortalidade (p=0,0001). Frente aos resultados, pode-se perceber que o estilo de vida e hist?rico familiar teve correla??o no progn?stico do CCR, assim como a express?o de MMP-2, MMP-9, VEGF alfa, E-caderina, Beta-catenina e Galectina-3 foram importantes marcadores de progn?stico na progress?o tumoral no c?ncer colorretal. / Except the non-melanoma skin tumors, colorectal cancer is the second most common in the Southeastern Region of Brazil, the third most common in the Southern and Central Regions. It is also the forth most common in the Northern Region and it is the fifth one in the Northeastern. To assess pathological and clinical variables of colorectal Cancer is crucial to know the possible conclusions for the survival of patients and point out the characteristics in the progress of tumor, such as the profile of tumor invasion and its angiogenesis. This work focuses on analyzing clinically and pathologically some settings in colorectal cancer patients (CRC) in the city of Natal and its countryside through those variables as parameters of prognosis and determine the level of protein expression, for instance: E-cadherin (E-cad), beta- -catenin (?-cat), galectin-3 (gal-3), matrix metalloproteinases (MMP) 2 and 9 and vascular-endothelial growth factor alpha (? VEGF) in the tumor tissues. A retrospective study was done in colorectal cancer cases in the regions of Rio Grande do Norte state from 1995 to 2005, specifically in Natal city/RN/Brazil. The pathological and clinical variables, such as: age, gender, ethnicity, lifestyle, family history, the location of the primary tumor, level of differentiation, TDM staging, modified Dukes?, treatment and survival were analyzed. The pathological and clinical data were collected from medical records through a specific form and were filed on Excel. A total of 534 patients were selected from the Pathology Department file in this institution, however, 176 patients were excluded. 358 patients were included for Epidemiological analysis and its clinical and pathological correlations were selected. 180 patients were also selected for histological and immunohistochemical studies. The tumor progression of these selected proteins mentioned before were analyzed. The Paraffin blocks of these samples were treated by Microarray Tissue technique and its blades subjected to immunohistochemistry to test the intensity of these proteins in tumor tissues. The results of this analysis were correlated with clinicopathologic variables of patients. Statistical analysis using the chi-frame Pearson test and analysis of midlife by Kaplan-Meier curve was also utilized. P values < 0.05 were considered statistically significant. The average age of our sample was 58.8 years and 51.7 % were female. Alcohol consumption has increased by 1.71 time the risk of death by CCR (p = 0.034) and tobacco consumption increased 2.7 times the chance of developing tumors of high TNM stage (p = 0.001). Cancer patients had a family history of 3,833 times the chance of developing the CCR (p = 0.002). The expression of MMP-2 showed a significant association with tumors of high TNM stage (p <0.046) and mortality (p = 0.041). The ? VEGF expression had statistically significant correlation with high TNM stage (p <0.009), degree of cell indifferentiation (p <0.025) and mortality (p <0.035). Expressions of E-cadherin and beta-catetina demonstrated tumor linked to high TNM stage (p = 0.0001) and Dukes? modified (p = 0.05), lesions in the rectum (p = 0.03 and p = 0.007, respectively), smoking (p = 0.05) and indifferentiation (p = 0.001). The expression of Gal-3 showed statistical significance with high TNM stage of patients (p = 0.01), smokers (p = 0.01), alcohol drinking (p = 0.03), indifferentiation (p = 0.0001) and mortality (p = 0.0001). Based on the results, therefore, we could realize that lifestyle and family history had correlation in the CCR prognosis, as well as MMP-2 expression, MMP-9, VEGF alpha, E-cadherin, Beta-catenin and Galectin-3 were important prognostic markers in tumor progression in colorectal cancer.

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