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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.
71

Análise da expressão do fator de transcrição TCF21/POD-1 e de genes do ciclo celular em tumores adrenocorticais humanos. / Analysis of TCF21/POD-1 transcriptor factor and cycle cells genes expression in adult adrenocortical tumors.

Passaia, Barbara dos Santos 31 May 2016 (has links)
As massas adrenocorticais são majoritariamente (70-80%) adenomas adrenocorticais (ACA). Os carcinomas adrenocorticais (ACC) são mais raros e de prognóstico restrito, com incidência de 1-2 casos por milhão, com alta taxa de reincidência (70-80%). Apesar dos tumores adrenocorticais (ACT) serem raros, no Brasil a incidência desses tumores em crianças é cerca de 10 vezes superior ao do restante do mundo, devido a uma mutação do gene TP53. Atualmente, o diagnóstico de massas adrenocorticais é realizado através dos critérios de Weiss, que possuem limitações, e por isso é intensa a busca de novos marcadores moleculares que facilite o diagnóstico de ACTs. POD-1/ TCF21 é um fator de transcrição do tipo helix-loop-helix básica (bHLH) expresso nos sítios de interação mesênquima-epitélio durante o desenvolvimento embrionário. Em ACTs, POD-1 regula a expressão endógena de SF-1 através da ligação na sequencia E-box da região promotora de SF-1, e nesses tumores parece estar relacionado negativamente com genes reguladores do ciclo celular, como BUB1B. BUB1B é um gene que codifica uma quinase com funções importantes durante o checkpoint mitótico. A expressão de BUB1B é considerada fator de prognóstico em diferentes tipos de tumores, inclusive em ACTs humanos, nos quais a expressão combinada de BUB1B e PINK1 (ΔCtBUB1B - ΔCtPINK1) mostrou-se um bom marcador de sobrevida em pacientes com ACC. PINK1, quinase 1 induzida por PTEN, é regulada principalmente pela mitocôndria, e em ACTs sua expressão está reduzida em ACC mais agressivos. Temos como hipótese que a expressão de POD-1 pode ter valor diferencial no diagnóstico de massas adrenocorticais, e que a análise da expressão combinada de POD-1, BUB1B e PINK1 pode ter valor diferencial para prognóstico de pacientes com ACT. Nesse trabalho foram analisados, por reação de qPCR com sondas Taqman, o cDNA obtido de 130 amostras de tumores: 79 adultos (44 ACAs e 35 ACCs), 35 crianças com menos de 5 anos de idade (27 ACAs e 8 ACCs) e 16 crianças de 5 a 18 anos de idade (6 ACAs e 10 ACCs). Nossos resultados mostram que POD-1 e BUB1B tem valor diferencial em ACT adulto e que a expressão combinada de POD-1 e BUB1B pode ser um marcador de prognóstico em pacientes com carcinoma adulto. Enquanto que, a expressão combinada de POD-1 e SF-1 pode ter valor de diagnóstico em pacientes pediátricos com menos de 5 anos. Em resumo, concluímos que estudos experimentais devem ser realizados para comprovar a relação entre os genes estudados, para que os resultados sejam sólidos o suficiente para serem utilizados no diagnóstico e prognóstico dos tumores adrenocorticais. / The adrenocortical masses are mostly (70-80%) adrenocortical adenomas (ACA). Adrenocortical carcinomas (ACC) are scarce and have limited prognosis, with an incidence of 1-2 cases per million and high recurrence rate (70-80%). Despite adrenocortical tumors (ACT) are rare in Brazil the incidence of these tumors in children is about 10 times higher than the rest of the world, due to a mutation of the TP53 gene. Currently, the diagnosis of adrenocortical mass is carried through Weiss criteria that have limitations, so it is intensive the search for new molecular markers that facilitate the diagnostic of ACTs. TCF21/POD-1 is a transcription factor helix-loop-helix type expressed in mesenchymal-epithelial sites of interaction during embryonic development. In ACTs, POD-1 regulates the expression of endogenous SF-1 through binding the E-box sequence of SF-1 promoter region, and seems to be negatively relates with cell cycle regulatory genes such as BUB1B. BUB1B is a gene encoding a kinase-with important function during mitotic checkpoint. The expression of BUB1B is considered a prognostic factor in different types of tumors, including ACTs. Combined expression of BUB1B and PINK1 (ΔCtBUB1B - ΔCtPINK1) has been shown to be a good marker of survival in adults with ACC, whereas the PINK1 expression is reduced in the most aggressive ACC. We hypothesized that the POD-1 expression may have differential value in the diagnosis of adrenocortical masses, and that the analysis of the combined expression of POD-1, BUB1B and PINK1 may have differential value for the prognosis of patients with ACT. In this work were analyzed by PCRq Taqman probes the cDNA obtained from 130 tumor samples: 79 adults (44 ACAs and 35 ACCs), 35 children under 5 years old (27 ACAs and 8 ACCs) and 16 children 5-18 years of age (6 ACAs and 10 ACCs). Our results show that POD-1 and BUB1B has differential value in adult ACT, and the combined expression of POD-1 and BUB1B may have a prognostic value in patients with adult carcinoma. In addition, the combined expression of POD-1 and SF-1 might have diagnostic value in pediatric patients younger than 5 years. In summary, we conclude that experimental studies should be conducted to confirm the relationship between the genes studied, so that the results are solid enough to be used in the diagnosis and prognosis of adrenocortical tumors.
72

A expressão dos marcadores de células-tronco, SF1 e DAX1 no desenvolvimento do córtex adrenal humano e sua associação com a via Wnt/beta-catenina na tumorigênese adrenocortical / The expression of stem cell markers, SF1 and DAX1 in the human adrenal cortex development and its association with the Wnt/beta-catenin pathway in adrenocortical tumorigenesis

Marcelo Machado Cavalcanti 02 May 2017 (has links)
Introdução: DAX1 (NR0B1), SF1 (NR5A1) e a via Wnt controlam o desenvolvimento de células progenitoras/tronco adrenais. NANOG, OCT4, SOX2 e STAT3 estão envolvidos na manutenção de células-tronco e têm papel em vários cânceres de diferentes tecidos. Ainda não está claro se esses fatores de transcrição interagem para promover a tumorigênese adrenocortical. Objetivo: Nos tumores adrenocorticais (TAC): avaliar o ganho de material genômico e a expressão de RNAm e proteica de DAX1 e SF1; avaliar a expressão de RNAm e proteica de marcadores de células-tronco (NANOG, OCT4, SOX2 e STAT3). No desenvolvimento do córtex adrenal: avaliar a expressão proteica desses genes. In vitro: avaliar a interação entre a via Wnt/Beta-catenina e a expressão de NANOG. Pacientes e Métodos: Painel de 30 córtices adrenais fetais humanos (20-38 semanas de gestação) e 14 pós-natais. Pacientes com TAC: 96 crianças/adolescentes (81% do sexo feminino, idade mediana de 1,6 anos [0,4 a 15,6 anos]) e 18 adultos (10 adenomas e 8 carcinomas, 89% do sexo feminino e idade mediana de 42,5 anos [21-66 anos]). Tecidos adrenais normais (controles para qPCR e MLPA): 13 crianças (idade mediana de 3 anos) e 13 adultos (mediana de idade de 48 anos). A expressão proteica de SF1, DAX1, STAT3, NANOG e OCT4 foi avaliada por imunohistoquímica nos TAC e nos córtices adrenais fetais e pós-natais. A expressão de RNAm de NR0B1, NR5A1, STAT3, NANOG e POU5F1 (OCT4) foi avaliada por qPCR nos TAC. Ganho ou perda de material genômico de NR0B1 e NR5A1 foi avaliada por MLPA nos TAC. In vitro, a expressão de NANOG (qPCR) foi avaliada em células adrenais H295 antes e após inibição da via Wnt/Beta-catenina com a substância PNU-74654. Resultados: Em adrenais fetais com 20 e 25 semanas de gestação detectou-se marcação intensa de SF1, DAX1, SOX2 e OCT4 na região subcapsular e marcação leve a moderada e difusa de STAT3 e NANOG. Após as 31 semanas e no período pós-natal, a marcação intensa de SF1 persistiu, porém a marcação de DAX1, STAT3, NANOG e OCT4 diminuiu ou desapareceu. Nos TAC, a marcação nuclear de SF1 foi positiva em 67% das amostras pediátricas e em 19% das amostras de adultos. Ganho de material genômico do NR5A1 foi observado em 71% dos TAC pediátricos e 33% de TAC adultos. Porém observou-se hipoexpressão do RNAm do NR5A1 em 84% dos TAC pediátricos. Nenhum ganho de material genômico ou aumento da expressão do RNAm do NR0B1 foi observado nos TAC pediátricos. Porém em 45% desses tumores detectou-se marcação nuclear. Nos TAC de pacientes adultos, houve aumento da expressão de RNAm de NR0B1 em 89% das amostras. Não se observou marcação de STAT3 nos TAC pediátricos e adultos. Porém nos pacientes adultos, a expressão do RNAm de STAT3 foi significativamente maior nos adenomas do que nos carcinomas. Por sua vez, a marcação nuclear do OCT4 associou-se significativamente com a ocorrência de metástases nos pacientes pediátricos. Nos TAC com a mutação p.S45P no gene da Beta-catenina detectou-se expressão significativamente aumentada do RNAm do NANOG. Além disso, após a inibição in vitro da via Wnt/Beta-catenina nas células tumorais adrenais houve redução significativa na expressão do RNAm de NANOG. Conclusão: Existe um padrão temporal na expressão de SF1, DAX1, STAT3, NANOG e OCT4 durante o desenvolvimento do córtex adrenal fetal, porém apenas a expressão de SF1 permanece no final da gestação e após o nascimento. TAC pediátricos exibem ganho de material gênico, aumento da expressão proteica e aparentemente redução paradoxal do RNAm do SF1 (NR5A1). Marcação nuclear de OCT4 se associa a fenótipo tumoral mais agressivo nos pacientes pediátricos. Parece exisitir interação entre a via Wnt/Beta-catenina e células-tronco, por meio do fator de transcrição NANOG, na tumorigênese adrenocortical. / Background: DAX1 (NR0B1), SF1 (NR5A1) and the Wnt pathway control adrenal stem/progenitor cells development. NANOG, OCT4, SOX2 and STAT3 are involved in the maintenance of stem cells and have role in various types of cancers in different tissues. It is still unclear whether these transcription factors interact to promote adrenocortical tumorigenesis. Objective: In adrenocortical tumors (ACT): to evaluate the gain of genomic material and the expression of mRNA and protein of DAX1 and SF1; to evaluate the mRNA and protein expression of stem cell markers (NANOG, OCT4, SOX2 and STAT3). In the development of the adrenal cortex: to evaluate the protein expression of these genes. In vitro: to evaluate the interaction between the Wnt/Beta-catenin pathway and NANOG expression. Patients & Methods: Panel of 30 fetal human adrenal cortices (20-38 gestational weeks) and 14 postnatal human adrenal cortices. ACT Patients: 96 children/ teenagers (81% female; median age of 1.6 years; 0.4-15.6 years) and 18 adults (10 adenomas and 8 carcinomas; 89% female; median age of 42.5 years; 21-66 years). Normal adrenal tissues (qPCR and MLPA controls): 13 children (median age of 3 years) and 13 adults (median age of 48 years). Protein expression of SF1, DAX1, STAT3, NANOG and OCT4 was assessed by immunohistochemistry in ACT, fetal and postnatal adrenal cortices. The mRNA expression of NR0B1, NR5A1, STAT3, NANOG and POU5F1 (OCT4) was assessed by qPCR in ACT. Gain or loss of NR0B1 and NR5A1 genomic material was assessed by MLPA in ACT. In vitro, NANOG expression (qPCR) was evaluated in H295 adrenal cells before and after inhibition of the Wnt/Beta-catenin pathway with PNU-74654. Results: In the adrenal glands at 20 and 25 gestational weeks, intense staining of SF1, DAX1, SOX2 and OCT4 was detected in the subcapsular region and a diffuse pattern mild to moderate staining of STAT3 and NANOG. After 31 weeks and in the postnatal period, intense SF1 staining persisted, but the staining of DAX1, STAT3, NANOG and OCT4 decreased or disappeared. In the ACT, the nuclear staining of SF1 was positive in 67% of pediatric samples and in 19% of adult samples. Gain of NR5A1 genomic material was observed in 71% of pediatric ACT and 33% of adult ACT. However, hypoexpression of NR5A1 mRNA was observed in 84% of pediatric ACT. No gain of genomic material or increase in mRNA expression of NR0B1 was observed in pediatric ACT. However, in 45% of these tumors nuclear staining was detected. In adult ACT, there was an increase in NR0B1 mRNA expression in 89% of the samples. No STAT3 staining was found in pediatric and adult ACT. However, in adult ACT, the STAT3 mRNA expression was significantly higher in adenomas than in carcinomas. In turn, the nuclear marking of OCT4 was significantly associated with the occurrence of metastases in pediatric patients. In the TACs with the p.S45P mutation in the Beta-catenin gene significantly increased NANOG mRNA expression was detected. In addition, after in vitro inhibition of the Wnt / Beta-catenin pathway in adrenal tumor cells there was a significant reduction in NANOG mRNA expression. Conclusion: There is a temporal pattern in the expression of SF1, DAX1, STAT3, NANOG and OCT4 during the development of the fetal adrenal cortex, but only SF1 expression remains at the end of gestation and after birth. Pediatric ACT show gain in NR5A1 gene material, increase in its protein expression but an apparent paradoxical reduction of mRNA. Nuclear staining of OCT4 is associated with more aggressive tumor phenotype in pediatric patients. There appears to be an interaction between the Wnt/Beta-catenin pathway and stem cells via NANOG, in adrenocortical tumorigenesis.
73

Relationship between serum corticosteroid level and telomere length/telomerase activity in spleen cells of Balb/c mice.

January 2007 (has links)
Chiu, Wang Kei. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2007. / Includes bibliographical references (leaves 95-110). / Abstracts in English and Chinese. / Abstract --- p.i / 摘要 --- p.iii / Contents --- p.v / Acknowledgements --- p.viii / Abbreviations --- p.ix / List of tables --- p.xii / List of figures --- p.xii / Chapter 1. --- Literature Review --- p.1 / Chapter 1.1 --- Cell cycle and chromosome replication --- p.1 / Chapter 1.2 --- Telomere-associated proteins --- p.4 / Chapter 1.3 --- Telomere repair protein --- p.6 / Chapter 1.4 --- Function of telomere --- p.9 / Chapter 1.5 --- Telomerase --- p.10 / Chapter 1.6 --- Factors affecting telomere length --- p.14 / Chapter 1.7 --- Stress and telomere length --- p.14 / Chapter 1.8 --- Definition of Stress --- p.16 / Chapter 1.9 --- Central nervous system components involved in stress response --- p.17 / Chapter 1.10 --- Glucocorticoid --- p.17 / Chapter 1.11 --- Physiological effects under the activation of stress system --- p.19 / Chapter 1.12 --- Effects of chronic hyperactivation of the stress system --- p.20 / Chapter 1.13 --- Hypothesis --- p.23 / Chapter 2. --- Materials and Methods --- p.24 / Chapter 2.1 --- Materials --- p.24 / Chapter 2.2 --- Experiment animals --- p.25 / Chapter 2.3 --- Methods --- p.26 / Chapter 2.3.1 --- Treatment schedule --- p.26 / Chapter 2.3.2 --- Organ extraction and serum preparation --- p.27 / Chapter 2.4 --- Serum corticosteroid assay --- p.27 / Chapter 2.5 --- Telomere length assay --- p.30 / Chapter 2.5.1 --- Genomic DNA extraction --- p.30 / Chapter 2.5.2 --- Genomic DNA digestion --- p.31 / Chapter 2.5.3 --- Southern blotting procedure --- p.32 / Chapter 2.6 --- Telomeric Repeat Amplification Protocol (TRAP) assay --- p.37 / Chapter 2.6.1 --- Extract preparation and protein concentration quanititation --- p.38 / Chapter 2.6.2 --- Real-time PCR reaction --- p.39 / Chapter 2.6.3 --- Melt Curve --- p.41 / Chapter 2.7 --- Detection of mouse telomerase reverse transcriptase component (mTERT) mRNA expression by reverse transcriptase- polymerase chain reaction (RT-PCR) --- p.42 / Chapter 2.7.1 --- Total RNA extraction --- p.42 / Chapter 2.7.2 --- RT-PCR --- p.44 / Chapter 2.7.3 --- Agarose gel electrophoresis of RT-PCR products --- p.45 / Chapter 2.8 --- Detection of mouse TERT (mTERT) by Western blotting --- p.46 / Chapter 2.8.1 --- Nuclear protein extraction --- p.46 / Chapter 2.8.2 --- Sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS-PAGE) --- p.47 / Chapter 2.9 --- Statistics --- p.49 / Chapter 3. --- Results --- p.51 / Chapter 3.1 --- Body and spleen weights of study animals --- p.51 / Chapter 3.2 --- Serum corticosterone level --- p.54 / Chapter 3.3 --- Telomere lengths of spleen --- p.54 / Chapter 3.4 --- Telomerase activity of spleen tissue --- p.58 / Chapter 3.5 --- Correlation between serum corticosterone level and telomere length --- p.65 / Chapter 3.6 --- Correlation between serum corticosterone level and telomerase activity --- p.66 / Chapter 3.7 --- Correlation between telomere length and telomerase activity --- p.67 / Chapter 3.8 --- Detection of telomerase reverse transcriptase component (mTERT) mRNA expression by RT-PCR --- p.69 / Chapter 3.9 --- Detection of mTERT by Western blotting --- p.72 / Chapter 3.10 --- Correlation between serum corticosterone level and mTERT mRNA /protein expression --- p.75 / Chapter 4. --- Discussion --- p.77 / Chapter 4.1 --- Serum corticosterone level in mice --- p.78 / Chapter 4.2 --- Mice body weight and spleen weight --- p.80 / Chapter 4.3 --- Telomere lengths in the spleen tissue --- p.83 / Chapter 4.4 --- Telomerase activity in spleens --- p.84 / Chapter 4.5 --- Correlation between serum corticosterone level and telomere length --- p.87 / Chapter 4.6 --- Correlation between serum corticosterone level and telomerase activity --- p.89 / Chapter 4.7 --- Mouse telomerase reverse transcriptase component (mTERT) mRNA expression --- p.89 / Chapter 4.8 --- Expression of mTERT protein --- p.90 / Chapter 4.9 --- Conclusion --- p.92 / Chapter 5. --- References --- p.95 / Chapter 6. --- Appendix --- p.111
74

A expressão dos marcadores de células-tronco, SF1 e DAX1 no desenvolvimento do córtex adrenal humano e sua associação com a via Wnt/beta-catenina na tumorigênese adrenocortical / The expression of stem cell markers, SF1 and DAX1 in the human adrenal cortex development and its association with the Wnt/beta-catenin pathway in adrenocortical tumorigenesis

Cavalcanti, Marcelo Machado 02 May 2017 (has links)
Introdução: DAX1 (NR0B1), SF1 (NR5A1) e a via Wnt controlam o desenvolvimento de células progenitoras/tronco adrenais. NANOG, OCT4, SOX2 e STAT3 estão envolvidos na manutenção de células-tronco e têm papel em vários cânceres de diferentes tecidos. Ainda não está claro se esses fatores de transcrição interagem para promover a tumorigênese adrenocortical. Objetivo: Nos tumores adrenocorticais (TAC): avaliar o ganho de material genômico e a expressão de RNAm e proteica de DAX1 e SF1; avaliar a expressão de RNAm e proteica de marcadores de células-tronco (NANOG, OCT4, SOX2 e STAT3). No desenvolvimento do córtex adrenal: avaliar a expressão proteica desses genes. In vitro: avaliar a interação entre a via Wnt/Beta-catenina e a expressão de NANOG. Pacientes e Métodos: Painel de 30 córtices adrenais fetais humanos (20-38 semanas de gestação) e 14 pós-natais. Pacientes com TAC: 96 crianças/adolescentes (81% do sexo feminino, idade mediana de 1,6 anos [0,4 a 15,6 anos]) e 18 adultos (10 adenomas e 8 carcinomas, 89% do sexo feminino e idade mediana de 42,5 anos [21-66 anos]). Tecidos adrenais normais (controles para qPCR e MLPA): 13 crianças (idade mediana de 3 anos) e 13 adultos (mediana de idade de 48 anos). A expressão proteica de SF1, DAX1, STAT3, NANOG e OCT4 foi avaliada por imunohistoquímica nos TAC e nos córtices adrenais fetais e pós-natais. A expressão de RNAm de NR0B1, NR5A1, STAT3, NANOG e POU5F1 (OCT4) foi avaliada por qPCR nos TAC. Ganho ou perda de material genômico de NR0B1 e NR5A1 foi avaliada por MLPA nos TAC. In vitro, a expressão de NANOG (qPCR) foi avaliada em células adrenais H295 antes e após inibição da via Wnt/Beta-catenina com a substância PNU-74654. Resultados: Em adrenais fetais com 20 e 25 semanas de gestação detectou-se marcação intensa de SF1, DAX1, SOX2 e OCT4 na região subcapsular e marcação leve a moderada e difusa de STAT3 e NANOG. Após as 31 semanas e no período pós-natal, a marcação intensa de SF1 persistiu, porém a marcação de DAX1, STAT3, NANOG e OCT4 diminuiu ou desapareceu. Nos TAC, a marcação nuclear de SF1 foi positiva em 67% das amostras pediátricas e em 19% das amostras de adultos. Ganho de material genômico do NR5A1 foi observado em 71% dos TAC pediátricos e 33% de TAC adultos. Porém observou-se hipoexpressão do RNAm do NR5A1 em 84% dos TAC pediátricos. Nenhum ganho de material genômico ou aumento da expressão do RNAm do NR0B1 foi observado nos TAC pediátricos. Porém em 45% desses tumores detectou-se marcação nuclear. Nos TAC de pacientes adultos, houve aumento da expressão de RNAm de NR0B1 em 89% das amostras. Não se observou marcação de STAT3 nos TAC pediátricos e adultos. Porém nos pacientes adultos, a expressão do RNAm de STAT3 foi significativamente maior nos adenomas do que nos carcinomas. Por sua vez, a marcação nuclear do OCT4 associou-se significativamente com a ocorrência de metástases nos pacientes pediátricos. Nos TAC com a mutação p.S45P no gene da Beta-catenina detectou-se expressão significativamente aumentada do RNAm do NANOG. Além disso, após a inibição in vitro da via Wnt/Beta-catenina nas células tumorais adrenais houve redução significativa na expressão do RNAm de NANOG. Conclusão: Existe um padrão temporal na expressão de SF1, DAX1, STAT3, NANOG e OCT4 durante o desenvolvimento do córtex adrenal fetal, porém apenas a expressão de SF1 permanece no final da gestação e após o nascimento. TAC pediátricos exibem ganho de material gênico, aumento da expressão proteica e aparentemente redução paradoxal do RNAm do SF1 (NR5A1). Marcação nuclear de OCT4 se associa a fenótipo tumoral mais agressivo nos pacientes pediátricos. Parece exisitir interação entre a via Wnt/Beta-catenina e células-tronco, por meio do fator de transcrição NANOG, na tumorigênese adrenocortical. / Background: DAX1 (NR0B1), SF1 (NR5A1) and the Wnt pathway control adrenal stem/progenitor cells development. NANOG, OCT4, SOX2 and STAT3 are involved in the maintenance of stem cells and have role in various types of cancers in different tissues. It is still unclear whether these transcription factors interact to promote adrenocortical tumorigenesis. Objective: In adrenocortical tumors (ACT): to evaluate the gain of genomic material and the expression of mRNA and protein of DAX1 and SF1; to evaluate the mRNA and protein expression of stem cell markers (NANOG, OCT4, SOX2 and STAT3). In the development of the adrenal cortex: to evaluate the protein expression of these genes. In vitro: to evaluate the interaction between the Wnt/Beta-catenin pathway and NANOG expression. Patients & Methods: Panel of 30 fetal human adrenal cortices (20-38 gestational weeks) and 14 postnatal human adrenal cortices. ACT Patients: 96 children/ teenagers (81% female; median age of 1.6 years; 0.4-15.6 years) and 18 adults (10 adenomas and 8 carcinomas; 89% female; median age of 42.5 years; 21-66 years). Normal adrenal tissues (qPCR and MLPA controls): 13 children (median age of 3 years) and 13 adults (median age of 48 years). Protein expression of SF1, DAX1, STAT3, NANOG and OCT4 was assessed by immunohistochemistry in ACT, fetal and postnatal adrenal cortices. The mRNA expression of NR0B1, NR5A1, STAT3, NANOG and POU5F1 (OCT4) was assessed by qPCR in ACT. Gain or loss of NR0B1 and NR5A1 genomic material was assessed by MLPA in ACT. In vitro, NANOG expression (qPCR) was evaluated in H295 adrenal cells before and after inhibition of the Wnt/Beta-catenin pathway with PNU-74654. Results: In the adrenal glands at 20 and 25 gestational weeks, intense staining of SF1, DAX1, SOX2 and OCT4 was detected in the subcapsular region and a diffuse pattern mild to moderate staining of STAT3 and NANOG. After 31 weeks and in the postnatal period, intense SF1 staining persisted, but the staining of DAX1, STAT3, NANOG and OCT4 decreased or disappeared. In the ACT, the nuclear staining of SF1 was positive in 67% of pediatric samples and in 19% of adult samples. Gain of NR5A1 genomic material was observed in 71% of pediatric ACT and 33% of adult ACT. However, hypoexpression of NR5A1 mRNA was observed in 84% of pediatric ACT. No gain of genomic material or increase in mRNA expression of NR0B1 was observed in pediatric ACT. However, in 45% of these tumors nuclear staining was detected. In adult ACT, there was an increase in NR0B1 mRNA expression in 89% of the samples. No STAT3 staining was found in pediatric and adult ACT. However, in adult ACT, the STAT3 mRNA expression was significantly higher in adenomas than in carcinomas. In turn, the nuclear marking of OCT4 was significantly associated with the occurrence of metastases in pediatric patients. In the TACs with the p.S45P mutation in the Beta-catenin gene significantly increased NANOG mRNA expression was detected. In addition, after in vitro inhibition of the Wnt / Beta-catenin pathway in adrenal tumor cells there was a significant reduction in NANOG mRNA expression. Conclusion: There is a temporal pattern in the expression of SF1, DAX1, STAT3, NANOG and OCT4 during the development of the fetal adrenal cortex, but only SF1 expression remains at the end of gestation and after birth. Pediatric ACT show gain in NR5A1 gene material, increase in its protein expression but an apparent paradoxical reduction of mRNA. Nuclear staining of OCT4 is associated with more aggressive tumor phenotype in pediatric patients. There appears to be an interaction between the Wnt/Beta-catenin pathway and stem cells via NANOG, in adrenocortical tumorigenesis.
75

Rôle de la signalisation PKA dans la zonation de la glande surrénale : modèles génétiques murins et mécanismes post-traductionnels / Role of PKA signaling in adrenocortical zonation : transgenic mouse models and post-translational mechanisms

Dumontet, Typhanie 07 July 2017 (has links)
Les hyperplasies micronodulaires pigmentées de la surrénale (PPNAD) sont les tumeurs endocrines les plus fréquentes d’un syndrome multinéoplasique d’origine génétique, le Complexe de Carney. Ces hyperplasies bilatérales sont associées à des mutations inactivatrices de PRKAR1A, le gène codant la sous-unité régulatrice R1 de la protéine kinase dépendante de l’AMPc (PKA). Ces tumeurs bénignes conduisent à une activation constitutive de la PKA responsable d’un hypercortisolisme indépendant de l’ACTH (syndrome de Cushing), associant diverses comorbidités telles que l’obésité centrale, le diabète, l’ostéoporose, des troubles de l’humeur ou encore des complications cardiovasculaires. Cependant, les mécanismes de cette tumorigenèse restent mal compris. Afin d’évaluer les conséquences de l’activation de la signalisation PKA sur l’induction tumorale et l’activité endocrine, l’équipe a précédemment généré un modèle de souris transgéniques reproduisant l’inactivation de Prkar1a dans la corticosurrénale. Ces souris développent une hyperplasie bilatérale composée de cellules présentant des caractéristiques fœtales naturellement absente d’une surrénale adulte. L’objectif général de ce travail de thèse était d’identifier l’origine des cellules constituant cette hyperplasie retrouvée dans le cortex interne des souris mutantes. Nous avons utilisé pour cela une approche génétique de lignage cellulaire afin de tracer chez la souris, l’origine de ces tumeurs après invalidation de Prkar1a dans les précurseurs du cortex définitif ou dans ceux du cortex fœtal. Les résultats montrent que l’activation de la signalisation PKA dans le cortex surrénalien adulte est suffisante pour promouvoir le développement d’hyperplasies surrénaliennes associées à la mise en place d’un syndrome de Cushing. L’invalidation de Prkar1a dans les précurseurs du cortex fœtal ne conduit à aucune anomalie endocrine ni tumorale. En revanche, l’activation de la signalisation PKA dans le cortex adulte favorise le renouvellement cellulaire centripète, l’identité fasciculée et sa conversion en identité réticulée dans la partie interne. L’activation de la signalisation PKA, conjointement à la croissance corticale, apparait donc comme un moteur possible de l’adrénarche, normalement restreinte aux grands primates.L’analyse transcriptomique des surrénales et les expériences de lignages cellulaires montrent que la prédisposition des femelles au syndrome de Cushing et au développement d’hyperplasies « pseudo-réticulée » pourraient reposer sur un dimorphisme sexuel des capacités de recrutement des cellules progénitrices et sur le métabolisme du cholestérol.En parallèle de ces travaux, l’exploration des mécanismes conduisant à la présence inappropriée de cellules « pseudo-réticulée » nous a amené à tester l’implication de la SUMOylation dans les défauts de zonation observés. Nos résultats montrent que l’activation de la signalisation PKA in vitro et in vivo exerce une hypoSUMOylation globale, d’origine transcriptionnelle. En accord avec cet effet, les nodules présents chez les patients atteints de PPNAD sont hypoSUMOylés. Enfin nous montrons chez les deux espèces, un gradient de SUMOylation régionalisé dans le cortex qui suggère l’implication de cette modification dans la zonation de la glande surrénale. / Primary Pigmented Nodular Adrenal Disease (PPNAD) is the most frequent endocrine manifestation of a rare, dominantly inherited multiple endocrine neoplasia syndrome, the Carney Complex. These bilateral hyperplasia are associated with inactivating mutations of PRKAR1A, the gene encoding the R1 regulatory subunit of cAMP-dependent protein kinase (PKA). These benign tumors lead to constitutive activation of PKA, responsible for an ACTH-independent hypertcortisolism (Cushing's syndrome), associating various comorbidities such as central obesity, diabetes, osteoporosis, mood disorders or cardiovascular complications. However, the mechanisms of tumorigenesis remain poorly understood. In order to evaluate the consequences of activation of PKA signaling on tumor induction and endocrine activity, the team previously generated a model of transgenic mice reproducing the inactivation of Prkar1a in the adrenal cortex. These mice develop bilateral hyperplasia composed of cells with fetal characteristics naturally absent from an adult adrenal gland.The general objective of this thesis was to identify the origin of the cells constituting this hyperplasia found in the internal cortex of the mutant mice. We used a genetic approach of cell lineage to trace the origin of these tumors after deletion of Prkar1a in the precursors of the adult or fetal cortex.The results show that activation of PKA signaling in the adult cortex is sufficient to promote the development of adrenal hyperplasia associated with Cushing's syndrome. The ablation of Prkar1a in the precursors of the fetal cortex does not lead to any endocrine or tumor abnormalities. On the contrary, activation of PKA signaling in the adult cortex promotes centripetal cell renewal, fasciculata identity and its conversion into reticularis identity in the internal part of the gland. The activation of PKA signaling, together with cortical growth, therefore appears to be a possible motor of adrenarche, normally restricted to human and some primates.Transcriptomic analysis of the adrenals and cell lineage experiments show that female predisposition to Cushing's syndrome and development of "pseudo-reticularis" hyperplasia may be based on sexual dimorphism of progenitor cell recruitment capacities and on metabolism of cholesterol.In parallel, the exploration of the mechanisms leading to the inappropriate presence of "pseudo-reticularis" cells led us to test the involvement of SUMOylation in the observed zonation defects. Our results show that the activation of PKA signaling in vitro and in vivo exerts a global hypoSUMOylation, of transcriptional origin. In agreement with this effect, the nodules present in patients with PPNAD are hypoSUMOylated. Finally, we show in both species a regionalized SUMOylation gradient in the cortex that suggests the implication of this modification in the zonation of the adrenal gland.
76

Adrenal Bioactivation and Toxicity of 3-MeSO<sub>2</sub>-DDE, o,p´-DDD and DMBA Investigated in Tissue Slice Culture

Lindhe, Örjan January 2001 (has links)
<p>I developed a precision-cut adrenal slice culture procedure to investigate cytochrome P450 (CYP) catalysed irreversible binding and adrenocorticolytic effects in human, rodent, and fish adrenal tissue, <i>ex vivo</i>. Autoradiography and radioluminography of exposed tissue slices showed that the potent adrenal toxicant 3-methylsulphonyl-2,2´-bis(4-chlorophenyl)-1,1´-dichloroethene (MeSO<sub>2</sub>-DDE) causes a selective metabolite binding in <i>zona fasciculata</i> (<i>ZF</i>), which is diminished by the CYP11B1 inhibitor metyrapone. MeSO<sub>2</sub>-DDE also reduces corticosterone secretion, increases 11-deoxycorticosterone secretion and causes mitochondrial degeneration in <i>ZF</i> cells in cultured mouse adrenal slices. ACTH treatment of mice induces CYP11B1 and increases irreversible MeSO<sub>2</sub>-DDE binding and toxicity in <i>ZF</i> cells. Metyrapone-sensitive binding of MeSO<sub>2</sub>-DDE is also observed in human <i>zona fasciculata/reticularis</i> (<i>ZF/ZR</i>) and 11-deoxycorti- sol/corticosterone secretion increases in MeSO<sub>2</sub>-DDE-exposed cultured human adrenal slices. The adrenocorticolytic drug 2-(2-chlorophenyl)-2-(4-chlorophenyl)-1,1-dichlorethane (o,p´- DDD, Mitotane<sup>®</sup>) is also bound in <i>ZF/ZR </i>but does not to impair hormone secretion in human adrenal slices at equimolar concentration. A targeted, presumably CYP1B1-catalysed irreversible binding of the adrenocorticolytic carcinogen 7,12-dimethylbenz[a]anthracene (DMBA) in <i>ZF/ZR </i>occurs in rat adrenal slices, whereas presumably CYP1A1-catalysed irreversible binding in endothelial cells is observed in CYP1-induced rats and mice. The rat-specific adrenocorticolytic activity of DMBA may rely on two independent pathological processes resulting in cell death and haemorrhage in the adrenal cortex. In Atlantic cod, selective binding of o,p´-DDD is observed in interrenal cells in cultured anterior kidney slices.</p><p>In conclusion, precision-cut adrenal slice culture is a simple <i>ex vivo</i> test system with which to investigate CYP-catalysed metabolite binding, alteredsteroid hormone secretion and target cell ultrastructure in human, experimental and wild animal tissue. The results imply that organisms under stress could be at increased risk of MeSO<sub>2</sub>-DDE induced adrenal toxicity. MeSO<sub>2</sub>-DDE is an expected human adrenal toxicant, which should be evaluated as a possible alternative in the therapy of adrenocortical hypersecretion and tumour growth.</p>
77

Adrenal Bioactivation and Toxicity of 3-MeSO2-DDE, o,p´-DDD and DMBA Investigated in Tissue Slice Culture

Lindhe, Örjan January 2001 (has links)
I developed a precision-cut adrenal slice culture procedure to investigate cytochrome P450 (CYP) catalysed irreversible binding and adrenocorticolytic effects in human, rodent, and fish adrenal tissue, ex vivo. Autoradiography and radioluminography of exposed tissue slices showed that the potent adrenal toxicant 3-methylsulphonyl-2,2´-bis(4-chlorophenyl)-1,1´-dichloroethene (MeSO2-DDE) causes a selective metabolite binding in zona fasciculata (ZF), which is diminished by the CYP11B1 inhibitor metyrapone. MeSO2-DDE also reduces corticosterone secretion, increases 11-deoxycorticosterone secretion and causes mitochondrial degeneration in ZF cells in cultured mouse adrenal slices. ACTH treatment of mice induces CYP11B1 and increases irreversible MeSO2-DDE binding and toxicity in ZF cells. Metyrapone-sensitive binding of MeSO2-DDE is also observed in human zona fasciculata/reticularis (ZF/ZR) and 11-deoxycorti- sol/corticosterone secretion increases in MeSO2-DDE-exposed cultured human adrenal slices. The adrenocorticolytic drug 2-(2-chlorophenyl)-2-(4-chlorophenyl)-1,1-dichlorethane (o,p´- DDD, Mitotane®) is also bound in ZF/ZR but does not to impair hormone secretion in human adrenal slices at equimolar concentration. A targeted, presumably CYP1B1-catalysed irreversible binding of the adrenocorticolytic carcinogen 7,12-dimethylbenz[a]anthracene (DMBA) in ZF/ZR occurs in rat adrenal slices, whereas presumably CYP1A1-catalysed irreversible binding in endothelial cells is observed in CYP1-induced rats and mice. The rat-specific adrenocorticolytic activity of DMBA may rely on two independent pathological processes resulting in cell death and haemorrhage in the adrenal cortex. In Atlantic cod, selective binding of o,p´-DDD is observed in interrenal cells in cultured anterior kidney slices. In conclusion, precision-cut adrenal slice culture is a simple ex vivo test system with which to investigate CYP-catalysed metabolite binding, alteredsteroid hormone secretion and target cell ultrastructure in human, experimental and wild animal tissue. The results imply that organisms under stress could be at increased risk of MeSO2-DDE induced adrenal toxicity. MeSO2-DDE is an expected human adrenal toxicant, which should be evaluated as a possible alternative in the therapy of adrenocortical hypersecretion and tumour growth.
78

In Vitro Studies of Adrenocorticolytic DDT Metabolites, with Special Focus on 3-methylsulfonyl-DDE

Asp, Vendela January 2010 (has links)
The DDT metabolite 3-methylsulfonyl-DDE (3-MeSO2-DDE) is bioactivated by cytochrome P450 11B1 (CYP11B1) in the adrenal cortex of mice and forms irreversibly bound protein adducts, reduces glucocorticoid secretion, and induces cell death selectively in cortisol-producing adrenocortical cells. 3-MeSO2-DDE has therefore been proposed as a lead compound for an improved adrenocortical carcinoma (ACC) therapy. The aims of this thesis were to (1) develop in vitro test systems based on murine and human adrenocortical cell lines and to (2) investigate the mechanisms behind 3-MeSO2-DDE toxicity in adrenocortical cells. The cytotoxic and endocrine-modulating effects of 3-MeSO2-DDE were compared to those of o,p′-DDD (mitotane), the current ACC therapy, and to those of several structurally analogous compounds in both murine and human cell lines. 3-MeSO2-DDE bioactivation and cytotoxicity proceeded in a similar manner in the murine adrenocortical Y-1 cell line as in mice in vivo. The effects were highly structure-specific. Moreover, 3-MeSO2-DDE formed irreversibly bound protein adducts and caused cell death also in the human H295R cell line, and was slightly more cytotoxic than o,p′-DDD. However, 3-MeSO2-DDE toxicity in human cells was not affected by the CYP11B1 inhibitor etomidate, suggesting that bioactivation in human cells is performed by additional/other enzyme(s) than CYP11B1. 3-MeSO2-DDE generated biphasic responses in cortisol and aldosterone secretion and in expression levels of the steroidogenic genes CYP11B1, CYP11B2, and StAR. Such hormesis-like responses were not seen for o,p′-DDD or the precursor DDT metabolite p,p′-DDE. In addition, the two o,p′-DDD enantiomers (R)-(+)-o,p′-DDD and (S)-(-)-o,p′-DDD exhibited slight differences in cytotoxic and endocrine-modulating activity in H295R cells. In conclusion, this thesis  provides  extended  knowledge  on  the  mechanisms  of  action  of 3-MeSO2-DDE and points out important differences in effects between murine and human cells. Lead optimisation studies of 3-MeSO2-DDE using the herein presented in vitro test systems are ongoing.
79

Characterization of the role of acid ceramidase in adrenocortical steroid hormone biosynthesis

Lucki, Natasha Chrystman 14 November 2011 (has links)
Sphingolipids modulate multiple cellular functions, including steroid hormone biosynthesis. Sphingosine is an antagonist ligand for the nuclear receptor steroidogenic factor 1 (SF-1), which is the primary transcriptional regulator of most steroidogenic genes. Furthermore, sphingosine-dependent repression of SF-1 function is dependent on the expression of acid ceramidase (ASAH1), an enzyme that forms sphingosine. Based on these data, I hypothesized that ACTH/cAMP signaling regulates ASAH1 function at both transcriptional and post-transcriptional levels. In addition, because SF-1 is predominantly a nuclear protein, I postulated that ASAH1 modulates SF-1 function and, therefore, steroidogenic gene expression by controlling the nuclear concentrations of SPH. To test these hypotheses, I first examined the effect of chronic ACTH/cAMP signaling on the transcription of the ASAH1 gene. Next, the functional significance of ASAH1 expression in adrenocortical cells was probed by generating an ASAH1-knockdown cell line. I subsequently characterized the role of ASAH1 as a transcriptional nuclear receptor coregulator. Finally, I defined the role of sphingosine-1-phosphate, a bi-product of ASAH1 activity, in the acute phase of cortisol biosynthesis. Using a variety of experimental approaches, I identified cAMP response element binding protein as an essential transcriptional activator of the ASAH1 gene. Analysis of adrenocortical cells lacking ASAH1 revealed that ASAH1 is a global regulator of steroidogenic capacity. Furthermore, I identified ASAH1 as a nuclear protein and defined the molecular determinants of the interaction between ASAH1 and SF-1. Collectively, this body of work establishes the integral role of ASAH1 in the regulation of ACTH-dependent adrenocortical cortisol biosynthesis.
80

Lavagem articular em osteoartrite de joelhos: um estudo controlado randomizado duplo-cego / Joint lavage in knee osteoarthritis: a randomized double-blind controlled study

Parmigiani, Leandro [UNIFESP] 26 November 2009 (has links) (PDF)
Made available in DSpace on 2015-07-22T20:50:24Z (GMT). No. of bitstreams: 0 Previous issue date: 2009-11-26 / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / Objetivo: Comparar efetividade e tolerância, a médio prazo, entre lavagem articular associada à infiltração intra-articular (IIA) com hexacetonide de triancinolona (HT) versus a IIA isolada de HT em pacientes com osteoartrite (OA) primária de joelhos. Material e Métodos: Foi realizado um estudo controlado, randomizado, duplo-cego com 60 pacientes que apresentavam OA primária de joelhos com dor em pelo menos um dos joelhos e índice de Kellgren Lawrence (KL) II e III divididos em dois grupos de intervenção: Grupo LA/HT: submetidos à LA com SF 0,9% (1000ml), finalizada pela introdução de HT 60 mg; Grupo HT: submetidos apenas à simulação de LA finalizada pela IIA de HT 60 mg. Os pacientes foram avaliados durante 12 semanas em cinco tempos de avaliação (T0, T1, T4, T8 e T12 semanas) por um avaliador “cego” através dos seguintes instrumentos de avaliação: escala visual analógica (EVA) para dor em repouso e ao movimento, goniometria, índice de WOMAC, questionário funcional de Lequesne, tempo de caminhada de 50 pés, porcentagem subjetiva de melhora, escala visual analógica de melhora (EVAM), segundo o paciente e segundo o avaliador, necessidade de anti-inflamatórios e analgésicos, número e tipo de efeitos colaterais locais. Foi realizada subanálise estatística na amostra segundo a classificação radiológica (KL II e KL III). Foi considerada uma significância estatística de 5%. Resultados: A média de idade foi de 63,7 (±8,59) anos, média de tempo de doença de 5,69 (±5,01) anos, proporção KL II/III de 33/27, sendo 88,3% de mulheres e 48,3.% de brancos. Apesar de ambos os grupos melhorarem estatisticamente na avaliação intragrupo, exceto para consumo de anti-inflamatório e EVAM, segundo o paciente, não houve diferença estatística na avaliação intergrupo para todas as variáveis estudadas no período de 12 semanas. De acordo com a subanálise realizada, observou-se, nos pacientes KL II, diferença estatística significante a favor do grupo HT para a variável flexão articular (p=0,03) no T4. Para os pacientes KL III, observou-se diferença estatística significante a favor do grupo LA/HT para as variáveis Lequesne (p=0,021) e WOMAC dor (p=0,01), assim como para a variável EVAM, segundo paciente (p=0,028) e avaliador (p=0,034) no T8. Conclusão: A combinação de LA à IIA com HT se mostrou mais efetiva a médio prazo que a IIA isolada com HT para o tratamento da OA primária de joelhos em pacientes KL III. Não houve diferença estatística quanto a tolerância destas duas intervenções. / Objective: Compare the medium-term effectiveness and tolerance intraarticular injection (IAI) with triamcinolone hexacetonide (TH) associated to joint lavage versus IAI with TH alone in patients with primary osteoarthritis (OA) of the knee. Methods: A randomized, double-blind, controlled study was carried out on 60 patients with primary OA of the knee, with pain in at least one of the knees and Grades II and III on the Kellgren-Lawrence index (KL II and III). Patients were randomized into two intervention groups: JL/TH Group – patients submitted to joint lavage with 0.9% saline solution (1000 ml) followed by a 60-mg injection of TH (3 ml); and TH Group – patients submitted to simulated joint lavage (sham) followed by a 60-mg injection of TH (3 ml). Patients were followed up for 12 weeks by a blinded observer using: visual analogue scale (VAS) for pain at rest and on movement; range of movement; Womac index; Lequesne’s questionnaire; timed 50-foot walk; subjective perception of improvement; Likert scale (0-5) for improvement assessment; the need for non-hormonal anti-inflammatory medication and analgesics; the local side effects. Results: Average age was 63.7 (± 8.59) years; mean duration of disease was 5.69 (± 5.01) years; the KL II/III proportion was 33/27; 88.3% were women and 48.3% were Caucasian. Although both groups demonstrated statistically significant improvement in the intra-group evaluation (except for Likert improvement scale according to the patient and the use of anti-inflammatory drugs), there were no statistically significant differences in the inter-group analysis for any of the variables studied over the 12-week period. In the KL II and III sub-analysis, there was a statistically significant difference regarding joint flexion among patients classified as KL II, favoring the TH group (p=0.03). For the KL III patients there were statistically significant differences favoring the JL/TH group regarding Lequesne score (p=0.021), WOMAC-pain score (p=0.01) and Likert improvement scale according to the patient (p=0.028) and the physician (p=0.034) at eight weeks. Conclusion: The combination of joint lavage and IAI with TH was more effective than IAI with TH alone in the treatment of primary OA of the knee in KL 3 patients. / TEDE / BV UNIFESP: Teses e dissertações

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