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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.
1

Significado clínico da expressão de VEGF-C e de podoplanina em carcinomas espinocelulares de boca / Clinical significance of VEGF-C and podoplanin expression in oral squamous cell carcinoma

Almeida, Aroldo dos Santos 20 February 2009 (has links)
A expressão do fator de crescimento endotelial vascular tipo C (VEGF-C) e de podoplanina pelas células malignas tem sido associada com a maior ocorrência de metástases regionais e/ou pior prognóstico para os pacientes com câncer de boca. O objetivo deste estudo foi avaliar o significado clinico da expressão de VEGF-C e podoplanina em 42 carcinomas espinocelulares (CEC) bem diferenciado de boca, com e sem comprometimento linfonodal, incluindo oito carcinomas verrucosos, tratados no Departamento de Cirurgia de Cabeça e Pescoço, do Hospital do Câncer A. C. Camargo, São Paulo, no período de 1980 a 2000. Os pacientes foram analisados quanto ao gênero, idade, cor, tabagismo, etilismo, localização do tumor primário, classificação pelo sistema TNM, tratamento, ocorrência de recidivas local e regional, metástase à distância, de segundo tumor primário, além da presença de infiltrações perineural, muscular, glandular e óssea e de embolizações vasculares. Analisou-se também o índice histopatológico de malignidade tumoral e as expressões imuno-histoquímica de VEGFC e de podoplanina pelas células malignas no front de invasão tumoral. A associação das expressões de VEGF-C e podoplanina com as variáveis estudadas foi calculada pelo teste quiquadrado. As probabilidades de sobrevida, acumuladas nos períodos de 5 e 10 anos calculadas pelo método de Kaplan-Meier e comparadas pelo teste de long-rank. A maioria dos CEC de boca, incluindo os carcinomas verrucosos, exibiu uma forte expressão de VEGF-C pelas células malignas. Houve uma tendência, sem associação estatisticamente significativa, dos pacientes com CEC de boca e forte expressão de VEGF-C apresentarem maior freqüência de recidivas locais e/ou regionais. A forte expressão de podoplanina foi significativamente associada com o gênero masculino (p=0,037), com o estadiamento T1 e T2 (p=0,037), com o estadio clínico I e II (p=0,027) e com a presença de infiltração glandular (p=0,003). As recidivas locais e regionais foram detectadas mais freqüentemente nos CEC de boca com forte expressão de podoplanina, porém sem diferença estatisticamente significativa, quando comparados com aqueles com expressão fraca da proteína. As taxas de sobrevida global e específica por câncer para os pacientes com tumores com forte expressão de VEGF-C e a taxa de sobrevida global para a forte expressão de podoplanina foram percentualmente menores do que aquelas dos pacientes com tumores com fraca expressão destas proteínas. O comprometimento linfonodal cervical se mostrou fator de prognóstico significativo (p=0,001) para os pacientes com câncer de boca. Estes resultados sugerem que a forte expressão de VEGF-C e podoplanina pelas células malignas juntamente com o comprometimento linfonodal regional são fatores indicativos de uma evolução clínica desfavorável e de um pior prognóstico para os pacientes com CEC bem diferenciados de boca. / The expression of vascular endothelial growth factor C (VEGF-C) and podoplanin by malignant cells has been associated with a greater incidence of regional metastasis and/or poor prognosis for patients with oral cancer. The purpose of this study was to evaluate the clinical significance of VEGF-C and podoplanin expression in 42 well-differentiated oral squamous cell carcinomas (OSCC), with and without lymph node involvement, including eight verrucous carcinoma, treated at the Department of the Head and Neck Surgery and Otorhinolaryngology, A. C. Camargo Cancer Hospital, São Paulo, from 1980 to 2000. Patients were evaluated according the following parameters: gender, age, ethnic group, tobacco and/or alcohol consumption, tumor location, TNM stage, treatment and clinical follow-up (recurrence, occurrence of a second primary tumor and death) and the presence of perineural, muscular, glandular and bone infiltrations or vascular embolizations. In addition, we investigated the histopathological malignancy index and the immunohistochemistry expression of VEGF-C and podoplanin by malignant cells in the invasive front tumor. Chisquare test or Fishers exact test was used to analyze the association of VEGF-C and podoplanin with demographic, clinical and microscopic variables in OSCC patients. The 5 and 10-year survival rates were calculated by Kaplan-Meier method and the comparison of the survival curves were performed using log rank test. Most of OSCC, including verrucous carcinoma, showed a high expression of VEGF-C by malignant cells. The OSCC patients with high expression of VEGF-C showed a tendency, without statistical significance, of local and/or regional recurrence. The overexpression of podoplanin was significantly associated with the male gender (p=0,037), with T1 and T2 stage (p=0,037), with I and II clinical stage (p=0,027) and with the presence of glandular infiltration (p=0,003). The local and regional recurrences were detected more frequently in OSCC with high expression of podoplanin, without statistical significant difference, when compared with those with low expression of the protein. The overall survival rates and cancer specific survival rates for OSCC patients with high VEGF-C expression and the overall survival rate for OSCC patients with podoplanin overexpression were lower than those of OSCC patients with low expression of these proteins. The cervical lymph node involvement was significant prognostic factor (p=0,001) for patients with oral cancer. These results suggest that the overexpression of VEGF-C and podoplanin by malignant cells and regional lymph node involvement are indicative factors of an unfavorable clinical outcome and a poor prognosis for patients with well-differentiated OSCC.
2

Significado clínico da expressão de VEGF-C e de podoplanina em carcinomas espinocelulares de boca / Clinical significance of VEGF-C and podoplanin expression in oral squamous cell carcinoma

Aroldo dos Santos Almeida 20 February 2009 (has links)
A expressão do fator de crescimento endotelial vascular tipo C (VEGF-C) e de podoplanina pelas células malignas tem sido associada com a maior ocorrência de metástases regionais e/ou pior prognóstico para os pacientes com câncer de boca. O objetivo deste estudo foi avaliar o significado clinico da expressão de VEGF-C e podoplanina em 42 carcinomas espinocelulares (CEC) bem diferenciado de boca, com e sem comprometimento linfonodal, incluindo oito carcinomas verrucosos, tratados no Departamento de Cirurgia de Cabeça e Pescoço, do Hospital do Câncer A. C. Camargo, São Paulo, no período de 1980 a 2000. Os pacientes foram analisados quanto ao gênero, idade, cor, tabagismo, etilismo, localização do tumor primário, classificação pelo sistema TNM, tratamento, ocorrência de recidivas local e regional, metástase à distância, de segundo tumor primário, além da presença de infiltrações perineural, muscular, glandular e óssea e de embolizações vasculares. Analisou-se também o índice histopatológico de malignidade tumoral e as expressões imuno-histoquímica de VEGFC e de podoplanina pelas células malignas no front de invasão tumoral. A associação das expressões de VEGF-C e podoplanina com as variáveis estudadas foi calculada pelo teste quiquadrado. As probabilidades de sobrevida, acumuladas nos períodos de 5 e 10 anos calculadas pelo método de Kaplan-Meier e comparadas pelo teste de long-rank. A maioria dos CEC de boca, incluindo os carcinomas verrucosos, exibiu uma forte expressão de VEGF-C pelas células malignas. Houve uma tendência, sem associação estatisticamente significativa, dos pacientes com CEC de boca e forte expressão de VEGF-C apresentarem maior freqüência de recidivas locais e/ou regionais. A forte expressão de podoplanina foi significativamente associada com o gênero masculino (p=0,037), com o estadiamento T1 e T2 (p=0,037), com o estadio clínico I e II (p=0,027) e com a presença de infiltração glandular (p=0,003). As recidivas locais e regionais foram detectadas mais freqüentemente nos CEC de boca com forte expressão de podoplanina, porém sem diferença estatisticamente significativa, quando comparados com aqueles com expressão fraca da proteína. As taxas de sobrevida global e específica por câncer para os pacientes com tumores com forte expressão de VEGF-C e a taxa de sobrevida global para a forte expressão de podoplanina foram percentualmente menores do que aquelas dos pacientes com tumores com fraca expressão destas proteínas. O comprometimento linfonodal cervical se mostrou fator de prognóstico significativo (p=0,001) para os pacientes com câncer de boca. Estes resultados sugerem que a forte expressão de VEGF-C e podoplanina pelas células malignas juntamente com o comprometimento linfonodal regional são fatores indicativos de uma evolução clínica desfavorável e de um pior prognóstico para os pacientes com CEC bem diferenciados de boca. / The expression of vascular endothelial growth factor C (VEGF-C) and podoplanin by malignant cells has been associated with a greater incidence of regional metastasis and/or poor prognosis for patients with oral cancer. The purpose of this study was to evaluate the clinical significance of VEGF-C and podoplanin expression in 42 well-differentiated oral squamous cell carcinomas (OSCC), with and without lymph node involvement, including eight verrucous carcinoma, treated at the Department of the Head and Neck Surgery and Otorhinolaryngology, A. C. Camargo Cancer Hospital, São Paulo, from 1980 to 2000. Patients were evaluated according the following parameters: gender, age, ethnic group, tobacco and/or alcohol consumption, tumor location, TNM stage, treatment and clinical follow-up (recurrence, occurrence of a second primary tumor and death) and the presence of perineural, muscular, glandular and bone infiltrations or vascular embolizations. In addition, we investigated the histopathological malignancy index and the immunohistochemistry expression of VEGF-C and podoplanin by malignant cells in the invasive front tumor. Chisquare test or Fishers exact test was used to analyze the association of VEGF-C and podoplanin with demographic, clinical and microscopic variables in OSCC patients. The 5 and 10-year survival rates were calculated by Kaplan-Meier method and the comparison of the survival curves were performed using log rank test. Most of OSCC, including verrucous carcinoma, showed a high expression of VEGF-C by malignant cells. The OSCC patients with high expression of VEGF-C showed a tendency, without statistical significance, of local and/or regional recurrence. The overexpression of podoplanin was significantly associated with the male gender (p=0,037), with T1 and T2 stage (p=0,037), with I and II clinical stage (p=0,027) and with the presence of glandular infiltration (p=0,003). The local and regional recurrences were detected more frequently in OSCC with high expression of podoplanin, without statistical significant difference, when compared with those with low expression of the protein. The overall survival rates and cancer specific survival rates for OSCC patients with high VEGF-C expression and the overall survival rate for OSCC patients with podoplanin overexpression were lower than those of OSCC patients with low expression of these proteins. The cervical lymph node involvement was significant prognostic factor (p=0,001) for patients with oral cancer. These results suggest that the overexpression of VEGF-C and podoplanin by malignant cells and regional lymph node involvement are indicative factors of an unfavorable clinical outcome and a poor prognosis for patients with well-differentiated OSCC.
3

Novel mechanisms for buffering the haemodynamic effects of dietary salt and the relevance of skin sodium in humans

Selvarajah, Viknesh January 2018 (has links)
Background: Hypertension is one of the most common diseases in the United Kingdom and it remains an important risk factor for cardiovascular morbidity and mortality. Dietary sodium is an important trigger for hypertension and humans show a heterogeneous blood pressure (BP) response to salt intake. The mechanisms for this have not been fully explained, with renal sodium handling thought to play a central role. Animal studies have shown that dietary salt loading results in Na+ accumulation and lymphangiogenesis in skin mediated by vascular endothelial growth factor-C (VEGF-C), both attenuating the rise in BP. This represents an additional system for maintaining BP and volume homeostasis in response to salt load. The focus of this thesis is to determine whether these dermal mechanisms exist in humans. Methods: The technique of measuring skin Na+ and K+ using inductively coupled plasma optical emission spectrometry was developed in a pilot study of healthy adults. In a further study in healthy adults, the effects of dietary salt modulation on skin Na+, the effect of sex and the relationship between skin Na+ and haemodynamic parameters and plasma VEGF-C were studied. Skin Na+ concentrations were expressed as the ratio Na+:K+ to correct for variability in sample hydration. The effect of dietary salt intake on skin gene expression of factors that potentially influence BP such as VEGF-C and the hypoxia inducible factor (HIF) transcription system was assessed, exploring possible mechanisms linking skin Na+ to haemodynamic variables. Results: Skin Na+:K+ increased with dietary salt loading and this effect appeared to be greater in men while only women showed a rise in ambulatory mean BP. Skin Na+:K+ correlated with blood pressure, stroke volume and peripheral vascular resistance in men, but not in women. No change was noted in plasma vascular endothelial growth factor-C. Conclusions: These findings suggest that the skin may buffer dietary Na+, reducing the hemodynamic consequences of increased salt and this may be influenced by sex. Skin Na+ may influence blood pressure, stroke volume and PVR.
4

Rôle et régulation du VEGF-C dans les cancers du rein à cellules claires / Role and regulation of VEGF-C in clear cell renal cell carcinomas

Ndiaye, Papa Diogop 08 December 2017 (has links)
Le carcinome à cellules rénales (RCC) exprimant le facteur inductible de l'hypoxie (HIF) en raison de l'inactivation du gène de von Hippel Lindau (vhl), représente un modèle d'hypoxie chronique. Le devenir des patients dépend du stade de dissémination des cellules tumorales. Par conséquent, déchiffrer les mécanismes de métastase est une préoccupation majeure. Le développement dépendant du VEGF-C (Vascular Endothelial Growth Factor C) d'un réseau lymphatique est en première ligne de propagation métastatique. Pour étudier le rôle de VEGFC dans la dissémination du RCC, nous avons étudié son expression dans l'hypoxie et nous avons invalidé son gène dans des lignées cellulaires humaines et murines. L'hypoxie régule négativement l'ARNm de VEGFC par une diminution de la transcription et de la stabilité de l'ARNm mais l'expression de la protéine VEGF-C est induite par l’hypoxie. Des capacités accrues de prolifération et de migration, et une meilleure expression des marqueurs mésenchymateux et des marqueurs souches caractérisent les cellules vegf-c -/-. Alors que les cellules vegfc -/- ne forment pas de tumeurs chez les souris immunodéficientes, elles développent des tumeurs agressives chez les souris immunocompétentes. La surexpression de VEGFC, est liée à une augmentation de la survie sans progression et globale chez les patients atteints de tumeurs non métastatiques alors qu'une diminution de la survie sans progression et globale est observée chez les patients métastatiques. Nos expériences décrivent une régulation subtile du VEGF-C par hypoxie et mettent en évidence son rôle bénéfique ou péjoratif. Par conséquent, le ciblage VEGF-C pour la thérapie doit être considéré avec prudence. / Hypoxic zones are common features of metastatic tumors. Renal cell carcinoma (RCC) expressing the Hypoxia Inducible Factor (HIF) because of inactivation of the von Hippel Lindau gene (vhl), represent models of chronic hypoxia. Their outcome depends on the extent of their dissemination at diagnosis. Therefore, deciphering the mechanisms of metastasis is a major concern. The Vascular Endothelial Growth Factor C (VEGFC)-dependent development of a lymphatic network is in front line of metastatic spreading. To address the role of VEGFC in RCC dissemination, we studied its expression in hypoxia and we invalidated its gene in human and mouse model cell lines of RCC. Hypoxia down-regulates VEGFC mRNA through a decrease in transcription and mRNA stability but concomitantly induced VEGFC protein expression. Increased proliferation and migration abilities, over-activation of the AKT signaling pathway and enhanced expression of mesenchymal and stem cell markers characterized vegfc-/- cells. Whereas vegfc-/- cells do not form tumors in immuno-deficient mice, they develop aggressive tumors in immuno-competent mice. Moreover, mouse RCC cells generate fast-growing tumors in mice invalidated for six1 or eya2, two major regulators of VEGFC expression. Lymphangiogenic markers overexpression including VEGFC is linked to increased disease-free and overall survival in patients with non-metastatic tumors whereas decreased progression-free and overall survival is observed for metastatic patients. Our experiments describe a subtle regulation of VEGFC by hypoxia and highlight its beneficial or pejorative role. Therefore, targeting VEGFC for therapy must be considered with caution.
5

Avaliação Imuno-histoquímica de VEGF-C e COX-2 em Carcinomas Papilíferos de Tireoide.

Pires, Janaína Steger de Oliveira Costa 28 June 2013 (has links)
Made available in DSpace on 2016-08-10T10:39:03Z (GMT). No. of bitstreams: 1 JANAINA STEGER DE OLIVEIRA COSTA PIRES.pdf: 1117981 bytes, checksum: f845b89570ca9e09aa37909b90cf688b (MD5) Previous issue date: 2013-06-28 / Thyroid câncer is the most common endocrine system malignant neoplasia. Although it is a relatively rare pathology, responsible for approximately 1% of new malignant disease cases, there has been recognized all over the world a tendency to increase its incidence. This study aimed to evaluate the expression of COX-2 and VEGF-C in patients diagnosed with Thyroid Papilary Carcinoma (TPC) in the city of Goiania, Goias State, Brazil, as well as the possible associations between this expression markers and the following factors: lymph node metastasis, distant metastasis, tumor size, age, adjacent tissue invasion and gender. In this regard, 165 thyroid papilary carcinoma cases diagnosed at the Araujo Jorge Hospital Patologic Anatomy Department in Goiania, Goias State, Brazil were analyzed. The molecular analysis was held by immunohistochemistry. Descriptive and comparative statistical analysis using Chi square test were held in this study. The study evaluated 165 patients who had documented histopathologic TPC diagnosis. The immunohistocemical analysis of the expression COX-2 e VEGF-C made possible to classify the expression COX-2 e VEGF-C in two groups, one of them with the expression &#8804; 50 % to COX-2 and VEGF-C (90 cases 54,5%; 102 cases 40,6%), and the other one with the expression > 50 % (50 cases 30,3%; 62 cases 37,6%). Significant statistical associations were observed between the size (p=0,0048; p<0,0001) and adjacent tissue invasion (p=0,0006; p<0,0001) with the expression of COX-2 and VEGF-C, and also between lymph node metastasis (p<0,0001) with expression VEGF-C. The collected data showed that the over expression COX-2 and VEGF-C in TPC cases can be important molecular biomarkers in thyroid papilary carcinoma prognosis. Our results corroborate to other studies that demonstrated the usability of these proteins to identify TPC patients, with a higher risk of disease progression because of its association with the presence of regional lymph node metastasis and with adjacent tissue invasion. / O câncer de tireóide é a neoplasia maligna mais comum do sistema endócrino. Embora seja uma patologia relativamente rara, responsável por aproximadamente 1% dos novos casos de doenças malignas, uma tendência no aumento de sua incidência tem sido reconhecida em várias partes do mundo. O objetivo desse estudo consistiu em avaliar a expressão de COX-2 e VEGF-C em pacientes diagnosticados com Carcinoma Papilífero da Tireóide (CPT) em Goiânia, bem como as possíveis associações entre a expressão desses marcadores e os seguintes fatores: metástase linfonodal, metástase à distância, tamanho do tumor, idade, extravasamento-invasão de tecidos adjacentes e gênero. Para isso foram analisados 165 casos de carcinomas papilíferos de tireoide diagnosticados no Setor de Anatomia Patológica do Hospital Araújo Jorge, em Goiânia, Goiás. A análise molecular foi feita por imuno-histoquímica. Análises estatísticas descritiva e comparativa com o teste Chi-quadrado foram usadas nesse estudo. O estudo avaliou 165 pacientes com diagnóstico histopatológico comprovado de CPT. A análise imuno-histoquímica da expressão de COX-2 e VEGF-C, possibilitou a classificação da expressão de COX-2 e VEGF-C em dois grupos, sendo um com expressão &#8804; 50 % para COX-2 e VEGF-C (90 casos 54,5%; 102 casos 40,6%), e outro com expressão > 50 % (50 casos 30,3%; 62 casos 37,6%). Associações estatisticamente significativas foram observadas entre o tamanho (p=0,0048; p<0,0001) e invasão de tecido adjacente (p=0,0006; p<0,0001) com a hiperexpressão de COX-2 e VEGF-C, e também entre metástase linfonodal (p<0,0001) com a expressão de VEGF-C. Os dados obtidos demonstraram que a superexpressão de COX-2 e VEGF-C nos CPT podem ser importantes biomarcadores moleculares no prognóstico do carcinoma papilífero de tireóide. Nossos resultados corroboram com outros estudos que demonstraram a utilidade dessas proteínas na identificação de pacientes com CPT, com maior risco de progressão da doença por sua associação com a presença de metástases para linfonodos regionais e com a invasão de tecido adjacente.
6

Potencial prognóstico da expressão de COX-2 e VEGF-C no adenocarcinoma colorretal de pacientes de um Hospital de referência do SUS no tratamento oncológico / Role of VEGF-C; COX-2; Colorectal; adenocarcinoma

MOTA, Eliane Duarte 23 March 2012 (has links)
Made available in DSpace on 2014-07-29T15:30:41Z (GMT). No. of bitstreams: 1 DissertacaoElianeDuarteMotaIPTSP.pdf: 4130183 bytes, checksum: 334a4dd3d5b4498f488ee03e5a9d338a (MD5) Previous issue date: 2012-03-23 / BACKGROUND: Colorectal adenocarcinoma (CRA) is a worldwide distributed pathology, and lymph node metastasis is associated with a poor prognostic outcome. Angiogenesis and lymphangiogenesis are correlated with metastasis. Vascular endothelial growth factor C (VEGF-C) and Cyclooxygenase 2 (COX-2) are molecules directly involved in those processes. We investigated the possible association of the expression of VEGF-C and COX-2 with clinical/pathology features and five year survival rate. MATERIALS AND METHODS: One hundred and thirty four cases of CRA from a Cancer Reference Hospital were randomly selected. The expression of VEGF-C and COX-2 was detected by immunohistochemistry and a univariate analysis was applied to evaluate the association between their expression and clinical stages, metastasis, and/or survival. RESULTS: COX-2 expression was observed in 98.67% of the adenocarcinoma cases while VEGF-C was found in 54.48% of the cases. COX-2 was highly expressed by all clinical stages of CRA, but its expression was not associated with LN metastasis, tumor infiltration or five years survival. A correlation was observed between LN metastasis and VEGF-C positivity (p=0.02) and clinical stages of the disease. The range of VEGF-C expressions was from 34.6% to 88.9% in stages 1 through 4, respectively. CONCLUSION: The majority of the CRA cases were positive for COX-2. It was observed association between the expression of VEGF-C and LN metastasis as well as with clinical stages of the disease, although no association was found to the overall five year survival rate. / INTRODUÇÃO: O adenocarcinoma colorretal (ACC) é uma doença de distribuição mundial e a metástase para linfonodos regionais está associada com pior prognóstico. A angiogênese e a linfangiogênese estão relacionadas com metástases. O Fator de crescimento endotelial vascular C (VEGF-C) e a Ciclooxigenase 2 (COX-2) são moléculas diretamente envolvidas nestes processos. Investigamos a possível associação da expressão de VEGF-C e COX-2 com características clínico/patológicas e a sobrevida em cinco anos. MÉTODOS: Cento e trinta e quatro casos de adenocarcinoma colorretal foram selecionados randomicamente. A expressão de COX-2 e VEGF-C foi detectada por imuno-histoquímica e as possíveis associações com aspectos clínicos e patológicos investigados. RESULTADOS: A expressão de COX-2 foi positiva em 133 (98,67%) pacientes e a expressão de VEGF-C foi encontrada em 73 (54,48%) pacientes. Não foram observadas associações significativas entre a expressão de COX-2 e metástases para linfonodos, invasão tumoral e nem com a sobrevida global em cinco anos. Quando a avaliação da expressão de VEGF-C foi realizada segundo Soumaoro et al, 2006, não associação com os aspectos estudados (p>0,05) e quando a expressão foi avaliada segundo Agaki et al., 2000, houve associação com metástases para linfonodos regionais o grau histológico do tumor (p=0,01) e com o estadiamento clínico (p=0,005). CONCLUSÃO: A maioria dos casos de ACR foram positivos para COX-2. Foram observadas associações entre a expressão de VEGF-C e metástases para linfonodos, bem como com os estadios clínicos da doença, embora, não tenha sido encontrada associação com a sobrevida em cinco anos.
7

Biological Effects and Action Mechanisms of Dietary Compounds

Sukamtoh, Elvira 09 July 2018 (has links)
The food that we consume contain many dietary compounds which are biologically active. In this thesis we will discuss the biological effects of dietary compounds and the mechanisms behind their activities. First, we studied on the anti-metastatic effects of curcumin, a dietary compound derived from turmeric, through lymphangiogenesis inhibition. Curcumin inhibited vascular endothelial growth factor-C (VEGF-C)-induced lymphangiogenesis in vivo and in vitro. Curcumin inhibited lymphangiogenesis, in part through suppression of proliferation, cell cycle progression and migration of lymphatic endothelial cells. Curcumin inhibited expressions of VEGF receptors (VEGFR2 and VEGFR3), as well as down-stream signaling such as phosphorylation of ERK and FAK. Finally, curcumin sulfate and curcumin glucuronide, two major metabolites of curcumin in vivo, had little inhibitory effect on proliferation of HMVEC-dLy cells. Our results demonstrate that curcumin inhibits lymphangiogenesis in vitro and in vivo, which could contribute to the anti-metastatic effects of curcumin. Next, we investigated the mechanisms underlying the cytotoxic activity of tert-butylhydroquinone (TBHQ), a widely used synthetic food antioxidant. Here we found that the biological effects of TBHQ are mainly mediated by its oxidative conversion to a quinone metabolite tert-butylquinone (TBQ). Co-addition of cupric ion (Cu2+) enhanced, whereas ethylenediaminetetraacetic acid (EDTA) suppressed the oxidative conversion of TBHQ to TBQ, and the biological activities of TBHQ in MC38 colon cancer cells. Finally, a structure and activity relationship study was done and together, these results suggest that the biological activities of TBHQ and other para-hydroquinones are mainly mediated by their oxidative metabolism to generate more biologically active quinone metabolites.
8

Carcinoma espinocelular : características clínicas intra-orais e demográficas em uma população do Sul do Brasil e potenciais interações com as células endoteliais linfáticas / Squamous cell carcinoma: clinical intraoral and demographics characteristics in a Southern Brazil population and potential interactions with lymphatic endothelial cells

Alves, Alessandro Menna 18 March 2013 (has links)
Made available in DSpace on 2014-08-20T14:30:10Z (GMT). No. of bitstreams: 1 Dissertacao_alessandro_menna_alves.pdf: 813449 bytes, checksum: 43f43131b0d8e54633d172ea87ffa722 (MD5) Previous issue date: 2013-03-18 / This dissertation was divided into two distinct works, which can be summarized as follows: Article 1: The oral squamous cell carcinoma (OSCC) is the most prevalent malignance in mouth, being an important public health problem. The aim of this study was to evaluate the clinical and epidemiological profile of the OSCC cases registered in a center of clinical and histopathological diagnosis, located in Southern Brazil. Eight hundred and six individuals with OSCC and its variants were included in this study, over 1959-2012 period. The variables recorded from the files were: age, gender, skin color, tumor location, size and evolution time of the lesions (referred by the patients), as well as, the presence of pain lymph nodes, habits of tobacco and alcohol, and also the profession. OSSC was more frequent in males (76.6%), with the majority of cases distributed between 51 and 70 years old (53.9%). The most prevalent sites were lower lip vermilion [23.3% (20.4; 26.4)], followed by lateral border/ventral surface of the tongue [20.2% (17.5; 23.2)], gingiva/alveolar ridge [18.1% (15.5; 21.0)], and floor of the mouth [14.9% (12.5; 17.5)]. A strong association between outdoor occupation and OSCC in lower lip vermilion was found. The OSCC lesions located in tongue, gingiva/alveolar ridge and floor of the mouth were commonly more painful, bigger than 2 cm, and frequently presenting lymph nodes involvement. Most of the results confirm the data from literature. Mouth self-examination should be recommended and campaigns of prevention and early detection of OSCC should be periodically performed in order to increase people s feelings of personal risk. Article 2: Inside the tumor microenvironment (TM) the neoplastic cells are in dynamic crosstalk with the vascular and lymphatic endothelial cells in order to allow the tumor to growth and metastasize. Hypothesizing that there is a crosstalk between lymphatic endothelial cells and tumor cells from squamous cell carcinoma (SCC) that plays an important role in metastasis, we aimed to identify potential interactions between lymphatic endothelial cells and tumor cells lines from SCCs, through some in vitro assays. Primary adult human dermal lymphatic microvascular endothelial cells (HMVECs) and the human head and neck SCC cell lines like A431, UM-SCC-1, UM-SCC-22A and UM-SCC-22B were cultured in their specific media. UM-SCC cells lines were treated with rhIL-6, being VEGF-C expression checked by Elisa. Baseline IL-6 was evaluated in HMEVCs using the same assay. Also the IL-6 receptor (IL-6R) was analyzed by Western blot in UM-SCC cells. Conditioned media from HMVECs were prepared with different treatments and incubated with SCC A431 cells, in order to verify the MMPs enzymatic activities by gelatin zymography. Our results demonstrated that there are interactions between tumor cells and LECs, since the LECs-CM were able to enhance MMP-2 gelatinolytic activity. Moreover, we showed that LECs secrete IL-6, and different SCC lines have receptors for this cytokine. Therefore, our results indicate some potential interactions between LECs and TCs, being necessary other studies to elucidate the involved signaling pathways / Esta dissertação foi dividida em dois trabalhos distintos, os quais podem ser resumidos da seguinte maneira: Artigo 1: O carcinoma espinocelular oral (CEO) é o tumor maligno mais prevalente na cavidade oral, sendo um importante problema de saúde pública. O objetivo deste estudo foi avaliar o perfil clínico e epidemiológico dos casos registrados de CEO em um centro de diagnóstico clínico e histopatológico, localizado no Sul do Brasil. Oitocentos e seis indivíduos com CEO e suas variantes histológicas foram incluídos neste estudo, num período entre 1959 e 2012. As variáveis anotadas dos arquivos foram: idade, sexo, cor da pele, sítio, tamanho, tempo de evolução (relatado pelo paciente), assim como a presença de dor, linfonodos palpáveis, hábitos de tabagismo e etilismo, e a profissão. CEO foi mais prevalente em homens (76,6%), com a maioria dos casos distribuídos entre os 51 e 70 anos de idade (53,9%). Os sítios mais prevalentes foram vermelhão do lábio inferior [23,3% (20,4; 26,4)], seguido por borda lateral/ventre de língua [20,2% (17,5; 23,2)], gengiva/rebordo alveolar [18,1% (15,5; 21,0)], e assoalho bucal [14,9% (12,5; 17,5)]. Foi encontrada uma forte associação entre ocupações ao ar livre e CEO de vermelhão de lábio inferior. As lesões localizadas na língua, gengiva/rebordo alveolar e assoalho bucal foram comumente mais dolorosas, maiores que 2 cm, a frequentemente apresentavam envolvimento de linfonodos. A maioria dos nossos resultados confirmam os dados da literatura. O autoexame bucal deveria ser recomendado e campanhas de prevenção e detecção precoce do CEO deveriam ser realizadas periodicamente na tentativa de aumentar o sentimento pessoal em relação ao CEO. Artigo 2: Dentro do microambiente tumoral (MT), as células neoplásicas estão numa constante crosstalk com células endoteliais linfáticas (CELs) e sanguíneas a fim de permitir o crescimento tumoral e metástase. Supondo que haja um crosstalk entre as CELs e as células do carcinoma espinocelular (CE) que exerce um importante papel na metástase, nosso objetivo foi identificar potenciais interações entre as CELs e linhagens celulares de CE, através de alguns ensaios in vitro. Células endoteliais linfáticas primárias adultas humanas da microvasculatura dérmica (HMVECs) e as linhagens de CE A431, UM-SCC-1, UM-SCC-22A e UM-SCC-22B foram cultivadas nos seus meios específicos. UM-SCC foram tratadas com rhIL-6, sendo a expressão de VEGF-C verificada por Elisa. Produção natural de IL-6 pelas HMVECs foi avaliada da mesma maneira. A presença de receptor de IL-6 (IL-6R) foi analisada por Western Blot nas linhagens UM-SCC. Meios condicionados(MC) das HMVECs foram preparados com diferentes tratamentos e incubados com a linhagem A431, a fim de verificar a atividade genatinolítica das MMPs por zimografia. Nossos resultados demonstraram que há interações entre as células tumorais e as CELs, uma vez que MC-CELS foram capazes de aumentar a atividade genatinolítica da MMP-2. Além disso, nós mostramos que as CELs secretam IL-6, e diferentes linhagens de CE possuem receptores para esta citocina. Sendo assim, nossos resultados indicam potenciais interações entre as LECs e as células tumorais, sendo necessário outros estudos para elucidar as vias de sinalização envolvidas
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Modulação da expressão de VEGF-C por mediador relacionado ao estresse em culturas de carcinomas espinocelulares de boca / Modulation of VEGF-C expression by stress related mediator in oral squamous cell carcinoma cell lines

Bruna Maria Rodrigues Vilardi 18 May 2011 (has links)
Os mediadores do estresse, epinefrina e norepinefrina, participam da modulação de diversos processos celulares como a proliferação, a migração celular e a apoptose durante a tumorigênese, influenciando assim, o crescimento e a progressão tumoral. A presença de receptores beta-adrenérgicos e sua expressiva resposta ao estímulo do neurohormônio norepinefrina foram identificadas em várias linhagens de células tumorais, incluindo o carcinoma espinocelular de boca. O objetivo deste estudo foi investigar a influência da norepinefrina na expressão do fator de crescimento endotelial vascular do tipo C (VEGF-C) em cultura de células de carcinoma espinocelular de boca que continham receptores beta adrenérgicos. As linhagens celulares (SCC-9 e SCC-25) foram estimuladas com norepinefrina em diferentes concentrações (0,1; 1 e 10 M) e com 1M de propranolol, sendo analisadas após 1, 6 e 24 horas. A expressão gênica e proteica de VEGF-C foram avaliadas, respectivamente, por RT-PCR em tempo real e por ELISA. A produção de RNAm para VEGF-C teve um comportamento irregular, com tendências a variações da expressão gênica (aumento e inibição). A dosagem proteica nos sobrenadantes das culturas de células malignas não refletiu a expressão gênica de VEGF-C. Somente na linhagem SCC-25 ocorreu uma inibição significativa da produção de VEGF-C (p<0,001) pelas células neoplásicas no ensaio de 24 horas após o estímulo com 10M de norepinefrina. Estes resultados sugerem que a expressão de VEGF-C nas linhagens de carcinomas espinocelulares humanos de boca, parece não ser mediado pela norepinefrina, via receptores beta-adrenérgicos. / The mediators of stress, epinephrine and norepinephrine, are involved in modulation of many cellular processes such as proliferation, migration and apoptosis influencing the tumor growth and progression. The presence of beta-adrenergic receptors and their significant response to stimulation of neurohormone norepinephrine has been identified in various tumor cell lines, including oral squamous cell carcinoma. The aim of this study was to investigate the influence of norepinephrine on the expression of vascular endothelial growth factor type C (VEGF-C) in oral squamous carcinomas cell lines that contained beta-adrenergic receptors. Cell lines (SCC-9 and SCC-25) were stimulated with different concentrations of norepinephrine (0.1, 1 and 10 mM) and 1 M of propranolol, and analyzed after 1, 6 and 24 hours. Gene and protein expressions of VEGF-C were evaluated, respectively, by real time PCR and by ELISA. The results showed an irregular behavior of the oral squamous carcinoma cell lines, with trends to increase or to inhibit the VEGF-C gene expression. Dosage protein in supernatant cultures of malignant cells did not reflect the gene expression of VEGF-C. Only in the SCC-25 cell line was detected a significant inhibition of VEGF-C production by neoplastic cells, twenty-four hours after stimulation with 10M norepinephrine (p<0,001). These results suggest that VEGF-C expression in oral squamous carcinomas cell lines seems not to be mediated by norepinephrine through the beta adrenergic receptor pathway.
10

Modulação da expressão de VEGF-C por mediador relacionado ao estresse em culturas de carcinomas espinocelulares de boca / Modulation of VEGF-C expression by stress related mediator in oral squamous cell carcinoma cell lines

Vilardi, Bruna Maria Rodrigues 18 May 2011 (has links)
Os mediadores do estresse, epinefrina e norepinefrina, participam da modulação de diversos processos celulares como a proliferação, a migração celular e a apoptose durante a tumorigênese, influenciando assim, o crescimento e a progressão tumoral. A presença de receptores beta-adrenérgicos e sua expressiva resposta ao estímulo do neurohormônio norepinefrina foram identificadas em várias linhagens de células tumorais, incluindo o carcinoma espinocelular de boca. O objetivo deste estudo foi investigar a influência da norepinefrina na expressão do fator de crescimento endotelial vascular do tipo C (VEGF-C) em cultura de células de carcinoma espinocelular de boca que continham receptores beta adrenérgicos. As linhagens celulares (SCC-9 e SCC-25) foram estimuladas com norepinefrina em diferentes concentrações (0,1; 1 e 10 M) e com 1M de propranolol, sendo analisadas após 1, 6 e 24 horas. A expressão gênica e proteica de VEGF-C foram avaliadas, respectivamente, por RT-PCR em tempo real e por ELISA. A produção de RNAm para VEGF-C teve um comportamento irregular, com tendências a variações da expressão gênica (aumento e inibição). A dosagem proteica nos sobrenadantes das culturas de células malignas não refletiu a expressão gênica de VEGF-C. Somente na linhagem SCC-25 ocorreu uma inibição significativa da produção de VEGF-C (p<0,001) pelas células neoplásicas no ensaio de 24 horas após o estímulo com 10M de norepinefrina. Estes resultados sugerem que a expressão de VEGF-C nas linhagens de carcinomas espinocelulares humanos de boca, parece não ser mediado pela norepinefrina, via receptores beta-adrenérgicos. / The mediators of stress, epinephrine and norepinephrine, are involved in modulation of many cellular processes such as proliferation, migration and apoptosis influencing the tumor growth and progression. The presence of beta-adrenergic receptors and their significant response to stimulation of neurohormone norepinephrine has been identified in various tumor cell lines, including oral squamous cell carcinoma. The aim of this study was to investigate the influence of norepinephrine on the expression of vascular endothelial growth factor type C (VEGF-C) in oral squamous carcinomas cell lines that contained beta-adrenergic receptors. Cell lines (SCC-9 and SCC-25) were stimulated with different concentrations of norepinephrine (0.1, 1 and 10 mM) and 1 M of propranolol, and analyzed after 1, 6 and 24 hours. Gene and protein expressions of VEGF-C were evaluated, respectively, by real time PCR and by ELISA. The results showed an irregular behavior of the oral squamous carcinoma cell lines, with trends to increase or to inhibit the VEGF-C gene expression. Dosage protein in supernatant cultures of malignant cells did not reflect the gene expression of VEGF-C. Only in the SCC-25 cell line was detected a significant inhibition of VEGF-C production by neoplastic cells, twenty-four hours after stimulation with 10M norepinephrine (p<0,001). These results suggest that VEGF-C expression in oral squamous carcinomas cell lines seems not to be mediated by norepinephrine through the beta adrenergic receptor pathway.

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