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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.
331

Avaliação da imunoexpressão de metalotioneína e ciclooxigenase-2 na fase precoce da carcinogênese experimental colônica associada à desnervação mientérica / Immunoexpression assessment of methallothionein and cyclooxigenase- 2 on early colonic experimental carcinogenesis associated to myenteric denervation, 2016

Minto, Stefania Bovo 01 July 2016 (has links)
O presente estudo objetivou avaliar os efeitos da inflamação e das expressões de metalotioneínas (MTs) e ciclooxigenase-2 (COX-2) na desnervação associada à carcinogênese experimental colônica, através da avaliação de imunoexpressão de COX-2, mieloperoxidase (MPO), neutrophil elastase (NE) e cluster de diferenciação 68 (CD68). Ainda, para analisar a presença de mutações e de danos ao material genético, realizou-se a técnica de imunoistoquímica para identificação de células imunomarcadas para MTs e histonas gamma-H2AX (H2AX). 52 ratos machos Wistar foram divididos em seus respectivos grupos: C (controle), B (controle dos animais desnervados), D (aplicação de DMH 30 mg/Kg ou 125 mg/Kg), BD (Cloreto de benzalcônio 0,3% na serosa intestinal, com posterior aplicação de DMH) e DB (aplicação de DMH, com posterior administração de BAC), sendo subdivididos de acordo com o tempo em que foram mortos, sendo: 24 horas, 72 horas (para avaliação da fase de iniciação) e 20 dias (para avaliação da fase de promoção). Como resultado, a desnervação foi capaz de proteger as células colônicas contra os efeitos desse carcinógeno, o que pode ser observado através da diminuição significativa da imunomarcação de MTs e de H2AX nos grupos desnervados. Ainda, através do aumento do número de células positivamente marcadas para MPO, NE e CD68, neutrófilos, macrófagos e/ou monócitos podem estar estritamente relacionados ao papel protetor da desnervação contra o câncer em um período de 20 dias após administração do DMH, uma vez que os animais desnervados apresentaram uma significativa diminuição desses marcadores. A desnervação aumentou o número de células imunomarcadas para MTs em animais que receberam apenas a aplicação do DMH e foram mortos após 20 dias - o que possivelmente diminuiu a expressão de COX-2 encontrada nesse estudo. Assim, sugere-se que os possíveis mecanismos protetores desempenhados pela desnervação contra o câncer sejam: (i) o aumento de MTs - conhecidamente protetoras à célula, e (ii) atuação da desnervação sobre o processo inflamatório, mais especificamente sobre neutrófilos e macrófagos e/ou monócitos. / This study evaluated the effects of inflammation and expression of metallothionein (MTs) and cyclooxygenase-2 (COX-2) on denervation associated to colonic experimental carcinogenesis by immunohistochemical evaluation of COX-2, myeloperoxidase (MPO), neutrophil elastase (NE) and cluster of differentiation 68 (CD68). Also, to analyze the presence of mutations and damage to DNA, was performed the immunohistochemical technique to identify positive immunostained cells for MTs and histone gamma-H2AX (H2AX). 52 male Wistar rats were divided into their respective groups: C (control), CB (control related to denervated animals), D (application of DMH 30 mg/Kg or 125 mg/kg), BD (0.3% benzalkhonium chloride administration in the intestinal serosa, and subsequent application of DMH) and DB (application of DMH with subsequent administration of BAC, in serous). The animals were subdivided according to euthanasia time: 24 hours, 72 hours (for evaluation of the initiation phase of the carcinogenesis process) and 20 days (for assessment of promoting phase). As result, the denervation process was able to protect colonic cells against the carcinogen effects, which can be seen through the significant decrease in immunostained cells for MTs and H2AX. Moreover, through the increased expression of MPO, NE and CD68, we found that neutrophils, macrophages and/or monocytes are closely related to inflammation on development of early colonic experimental carcinogenesis (20 days groups) - which was reverted by denervation. The denervation increased the number of immunostained cells for MTs in denervated animals that received application of DMH - what could possibly decreased COX-2 expression found in this study. Thus, it is suggested that the possible protective mechanisms performed by denervation against cancer are: (i) increased MTs - known to be protective to the cell, and (ii) actuation on inflammatory process, more specifically on neutrophils and macrophages and/or monocytes.
332

Efeitos do exercício físico associado à luz contínua na carcinogênese colônica em ratos / Influence pineal gland on experimental colon carcinogenesis in rats submitted to physical exercise

Frajacomo, Fernando Tadeu Trevisan 29 April 2010 (has links)
O exercício físico tem sido proposto como uma terapia não farmacológica eficaz para a prevenção e tratamento de neoplasias, com destaque ao câncer de cólon. O presente estudo visa investigar o papel da glândula pineal sobre carcinogênese colônica experimental de ratos submetidos ao exercício físico Dessa forma, propusemos investigar os biomarcadores colônicos de câncer, foco de cripta aberrante (FCA), antígeno nuclear de proliferação nuclear (PCNA), expressão de ciclooxigenase-2 (COX-2) e Caspase 3. Além de parâmetros oxidativos hepáticos de peroxidaçao lipídica e gluationa reduzida (GSH). O Estudo foi conduzido através dos grupos experimentais controle (C), luz contínua (L), Exercício (E) e luz contínua associada ao Exercício (LE) e os mesmos grupos expostos ao carcinógeno químico 1,2-Dimetilhidrazina (DMH). Exercício físico foi realizado pelo modelo de natação, 5 dias por semana durante 10 semanas. Após o periodo de treinamento, os animais foram sacrificados, sendo coletadas amostras de sangue e fígado e colón para análises. O estudo do fígado revelou uma significativa influência do DMH na modulação dos parâmetros oxidativos. Já as análises colônicas dos FCAs e do PCNA mostraram-se controlados pelo exercício físico realizado em condições de normais do ritmo circadiano ao passo que em condições de desbalanço fisiológico da glândula pineal pela exposição luz constante, esses mesmos efeitos foram revertidos em comparação ao demais grupos (LED>LD>D>ED=p<0.001), aumento este acompanhado pela redução dos níveis plasmáticos de melatonina neste grupo. Em conclusão, nossos dados alertam para a forte influência da glândula pineal sobre o complexo de adapatações do exercício físico no tecido colônico de ratos expostos a um carcinógeno químico. / Physical activity has been proposed as a nonpharmacologic therapy for the prevention and treatment of cancer patients, with emphasis on colon cancer. The current study aims to investigate the role of the pineal gland on experimental colon carcinogenesis in rats submitted to physical exercise. We proposed to analyze cancer colonics biomarkers, Aberrant Foci Crypt (ACFs), proliferating cell nuclear antigen (PCNA) and Caspase-3, inflammation parameters cyclooxigenase-2 (COX-2) and liver oxidative enzymes reduced glutathione (GSH) and lipid peroxidation (MDA). Experimental design was constructed by control group (C), continuous light (L), exercise (E) and continuous light plus exercise (LE) and the same groups with chemical carcinogen 1,2 dimethyl-hydrazine (DMH). Exercise training groups were performed swimming exercise 5 d-wk1 for 10 wk. After training period rats were sacrificed. Blood samples and liver were collected to analyses and colon was processed for histological and immunohistochemistry examination. The study of the liver revealed a significant effect of DMH in the modulation of oxidative parameters. Since the analysis of colonic FCAs and PCNA were shown to be controlled by exercise carried out with a normal circadian rhythm while in conditions of physiological imbalance of the pineal gland by constant light exposure, these effects were reversed in comparison to other groups (LED> LD> D> ED = p <0.001), increase accompanied by reduced plasma levels of melatonin in this group. In conclusion, our data call attention to the strong influence of the pineal gland on the complex adaptations of physical exercise on colonic mucosa of rats exposed to a chemical carcinogen.
333

The role of cathelicidin in gastric tissue repair and carcinogenesis. / Cathelicidin在胃组织修复和胃癌发生中的作用 / CUHK electronic theses & dissertations collection / Cathelicidin zai wei zu zhi xiu fu he wei ai fa sheng zhong de zuo yong

January 2009 (has links)
Cathelicidin, a pleiotropic host defense peptide, has been shown to promote cutaneous wound repair and reaches high levels in the gastric mucosa during acute Helicobacter pylori-associated inflammation. The expression of cathelicidin, nevertheless, has also been found to be down-regulated in gastric hyperplastic polyps, tubular adenomas, and adenocarcinomas. We therefore hypothesized that cathelicidin might contribute to gastric ulcer healing and suppress gastric cancer growth. In this study, the role of this peptide in gastric tissue repair and carcinogenesis was investigated. / Collectively, this study demonstrates for the first time that cathelicidin can promote tissue repair and suppress cancer growth in stomachs by eliciting differential cellular signaling and responses in normal and cancerous gastric epithelial cells. These unique biological activities may open up a novel therapeutic avenue for the treatment of these diseases. / Concerning gastric carcinogenesis, the human cathelicidin LL-37 lowered gastric cancer cell proliferation and delayed G1-S transition in vitro and inhibited the growth of gastric cancer xenograft in vivo. Knockdown or induction of endogenous LL-37 by RNA interference or 1alpha,25-dihydroxylvitamin D3, respectively, increased or suppressed cell proliferation. In this connection, LL-37 increased bone morphogenetic protein (BMP) signaling, manifested as increases in BMP4 expression and the subsequent Smad1/5 phosphorylation and the induction of Smad6 and Smad7. Moreover, LL-37 increased the expression of p21Waf1/Cip1, whose induction was abolished by the knockdown of BMP receptor II. Knockdown of BMP receptor II or p21Waf1/Cip1 also abrogated the anti-mitogenic action of LL-37. The activation of BMP signaling by LL-37 was accompanied with the inhibition of chymotrypsin-like and caspase-like activity of proteasome. In this regard, proteasome inhibitor MG-132 mimicked the effect of LL-37 by increasing BMP4 mRNA expression and Smad1/5 phosphorylation. In addition, cyclin E 2 was down-regulated by LL-37 via a BMP-independent mechanism. Further analysis of clinical samples revealed that LL-37 and p21Waf1/Cip1 mRNA expression were both down-regulated in gastric cancer tissues and their expression were positively correlated. These findings indicate that LL-37 inhibits gastric cancer cell proliferation through activation of BMP signaling via a proteasome-dependent mechanism. / In relation to gastric ulcer healing, results revealed that ulcer induction in rats increased the expression of rat cathelicidin rCRAMP in the gastric mucosa. Further increase in expression of rCRAMP by local injection of rCRAMP-encoding plasmid promoted ulcer healing by enhancing cell proliferation and angiogenesis. rCRAMP directly stimulated proliferation of cultured rat gastric epithelial cells (RGM-1), which was abolished by inhibitors of matrix metalloproteinase (MMP), epidermal growth factor receptors (EGFR) tyrosine kinase, or mitogen-activated protein kinase/extracellular signal-regulated kinase (ERK) kinase. rCRAMP also increased EGFR and ERK1/2 phosphorylation via an MMP-dependent mechanism. Knockdown of transforming growth factor alpha (TGFalpha), which is a ligand of EGFR, by small interfering RNA completely nullified the mitogenic signals evoked by rCRAMP in RGM-1 cells. These findings suggest that rCRAMP exhibits pro-healing activity in stomachs through TGFalpha-dependent transactivation of EGFR and its related signaling pathway to induce proliferation of gastric epithelial cells. / Wu, Ka Kei. / Adviser: Joseph J. Y. Sung. / Source: Dissertation Abstracts International, Volume: 71-01, Section: B, page: 0252. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2009. / Includes bibliographical references (leaves 153-178). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Electronic reproduction. Ann Arbor, MI : ProQuest Information and Learning Company, [200-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstracts in English and Chinese.
334

Mouse orthotopic model for therapeutic bladder cancer research.

January 2014 (has links)
Objectives: To establish a mouse orthotopic bladder cancer model with consistent tumor-take rate. This orthotopic model was subsequently used to evaluate small animal imaging techniques and investigate new therapeutic agents for bladder cancer treatment. / Materials and Methods: Different orthotopic implantation techniques have been tested. MBT-2 cells and syngeneic C3H/He mice were used in all experiments. Chemical bladder pre-treatment with different agents (saline, hydrochloric acid, trypsin and poly-L-lysine) and different concentration of instilled tumor cells (1 x 10⁶ or 2 x 10⁶) were investigated. In the second part of the experiment, trans-abdominal micro-ultrasound imaging (MUI) technique was investigated and validated. Bladder tumor growths were monitored with longitudinal measurement. Mice were killed at every MUI session. Bladder tumor volumes were measured and correlated with gross stereomicroscopy. Using the optimized orthotopic bladder cancer model, targeted contrast enhanced micro-ultrasound imaging has been investigated. VEGFR2 targeted contrast agent was prepared and injected intravenously before imaging sessions. The intra-tumoral perfusion, VEGFR2 expression and blood volume in real time were quantified. Contrast enhanced MUI was performed on Days 14 and 21. The feasibility of targeted contrast enhanced micro-ultrasound imaging was confirmed. After the establishment of orthotopic model and in vivo molecular imaging techniques, this robust platform was used for investigating new treatment agent in localized bladder cancer. Tumor-bearing mice were randomized into control and sunitinibtreated (40 mg/kg) groups. Tumor volume, intra-tumoral perfusion, and in vivo VEGFR2 expression were measured using a targeted contrast-enhanced micro-ultrasound imaging system. The effects of sunitinib malate on angiogenesis and cellular proliferation were measured by CD31 and Ki-67 immunohistochemistry. The clinical outcomes including total bladder weight, tumor stage, and survival were evaluated. / Results: A consistent tumor take-rate of over 90% was achieved by using poly-L-lysine pretreatment with 2 x 10⁶ MBT-2 cells in all of the experiments. MUI identified all tumors that were present on final histology. Measurements of tumor size by MUI and gross microscopy had a high correlation coefficient (r = 0.97). Measurements of intra-tumoral perfusion and in vivo VEGFR2 expression were also proved to be feasible. After the technical refinement and modification, complete measurements could be performed in all mice (n = 10) at 2 consecutive imaging sessions. No adverse effects occurred due to anesthesia or the ultrasound contrast agent. This is the first report of applying targeted contrast enhanced MUI in orthotopic bladder cancer model. Finally, sunitinib was found to have significant tumor growth inhibition in both in vitro and in vivo experiments. In the orthotopic model, tumors in sunitinib-treated mice had reduced tumor volume and stage, lower proliferation index and micro-vessel density. Sunitinib prolonged survival in tumor-bearing mice as compared to control group. / Conclusions: The development of reliable orthotopic animal models assists in the discovery of novel therapeutic agents. The establishment in the methods of implantation with improved tumor-take rate and the advances in imaging technology form the important foundation of basic research in bladder cancer. Trans-abdominal MUI is proven to be a valuable tool for translational studies involving orthotopic mouse bladder cancer models. Furthermore, the first report of the application of targeted contrast enhanced MUI in deep-seated tumor in bladder has been published. It enables investigators to monitor tumor angiogenesis and vascular changes after treatment. It will be useful for direct, noninvasive, in vivo evaluation of anti-angiogenesis therapeutic agents. The preclinical study has demonstrated the activities of a new class of targeted therapy against localized bladder cancer in an orthotopic mouse model. Sunitinib inhibits tumor growth and thus decreases the tumor burden and prolongs survival compared with placebo. These results provide a rationale for future clinical trials using VEGFR-targeted treatments of localized bladder cancer in the neo-adjuvant and adjuvant settings. / Chan, Shu Yin Eddie. / Thesis (M.D) Chinese University of Hong Kong, 2014. / Includes bibliographical references (leaves 189-212).
335

O estudo do NF-KB e da Survivina na progressão do Câncer Colorretal / The study of NF-KB and survivin in the progression of colorectal cancer.

Brunaldi, Mariângela Ottoboni 25 March 2013 (has links)
O câncer colorretal (CCR) é importante causa de morte no Brasil, representando a segunda causa de morbimortalidade por câncer nas regiões Sudeste e Sul. Foi uma das primeiras neoplasias malignas a ter modelo de carcinogênese identificado. Os objetivos deste trabalho foram avaliar a expressão do NF-KB e da survivina na progressão do CCR, sua relação com alvos moleculares envolvidos na sobrevivência celular [proibitina, fator de necrose tumoral (TNFR1), p53, B- catenina]; invasão (metaloproteinases 2 e 9 - MMP), angiogênese (fator de crescimento endotelial vascular VEGF) e apoptose (caspase 3 e método do Túnel). Trata-se de estudo retrospectivo baseado na análise histopatológica de dezoito casos de adenomas com displasia de alto (AG) e baixo grau (BG), respectivamente; dez casos de adenocarcinoma bem, moderado e pouco diferenciado, respectivamente, nove casos de lesões serrilhadas e nove biópsias colorretais (controle) selecionados aleatoriamente no Serviço de Patologia do Hospital das Clínicas da Faculdade de Medicina de Ribeirão Preto da Universidade de São Paulo, no período de 2000 a 2009. Foram construídos arranjos de matriz tecidual para representar os casos de adenocarcinomas e cinco casos de adenomas >1 cm de diâmetro. A detecção do NF-KB foi realizada pelo método de Southwestern imunoistoquímica. Avaliou-se a expressão imunoistoquímica da survivina, proibitina, TNFR1, p53, B-catenina, MMPs 2 e 9, VEGF, caspase 3 e Túnel. Não observamos expressão imunoistoquímica do NF-KB em 70% dos casos de adenocarcinomas, em 72% dos adenomas AG e em 89% das lesões serrilhadas; a marcação foi positiva em 66% e 56% dos casos de adenoma do BG e controle, respectivamente. Expressões da survivina, proibitina citoplasmática, TNFR1, p53, MMP 2 e 9 foram crescentes na seqüência adenoma-carcinoma, sem aparente modulação pelo NF-KB. A survivina suprimiu ação da caspase 3, exceto nos adenomas BG e controle, com baixos níveis de apoptose ao túnel. Lesões serrilhadas e controle apresentaram baixa expressão do TNFR1 e da proibitina citoplasmática, ausência de marcação da p53 e MMPs 2 e 9, exceto um caso controle. Identificou-se marcação nuclear da proibitina nos adenocarcinomas pouco diferenciados, adenomas AG e BG. A expressão da p53 relacionou-se ao grau de displasia nos adenomas e à desregulação da survivina. Observou-se expressão citoplasmática e nuclear da B- catenina nos adenocarcinomas, adenomas AG e BG. As lesões serrilhadas exibiram expressão citoplasmática em 44% dos casos. O grupo controle exibiu expressão preservada da B-catenina. Identificou-se expressão do VEGF nos adenocarcinomas, relacionada à perda de diferenciação celular, presença de metástases, não correlacionada ao NF-KB. Com base nos nossos resultados, sugerimos a desregulação da B- catenina como possível responsável pela inibição do NF-KB; além de sua participação na desregulação da survivina juntamente com a p53. As lesões serrilhadas não exibiram indícios sugestivos de inibição do NF- KB pela B-catenina.A survivina, devido propriedades anti-apoptóticas, emerge como potencial alvo terapêutico no tratamento do CCR, confirmando estudos anteriores. / Colorectal cancer (CRC) is an important cause of death in Brazil, representing the second leading cause of cancer mortality in the Southeast and South. It was among the first malignancies that have the carcinogenesis model identified.The aim of this study was to evaluate the expression of NF-KB and survivin in the progression of CRC, its relationship with molecular targets involved in cell survival [prohibitin, tumor necrosis factor (TNFR1), p53,B-catenina], invasion (metalloproteinases 2 and 9 - MMP), angiogenesis (vascular endothelial growth factor VEGF) and apoptosis (caspase 3 and method Tunnel). This is a retrospective study based on the histopathological analyses of eighteen cases of high- (HG) and low- grade dysplastic (LG) adenomas, respectively; ten cases of adenocarcinoma well, moderately and poorly differentiated, respectively, nine cases of serrated lesions e nine biopsies (control); randomly selected in the Pathology Service of the University Hospital of the Faculty of Medicine of Ribeirão Preto, University of São Paulo from 2000 to 2009. Tissue microarray were constructed to represent the cases of adenocarcinomas and five cases of adenomas > 1cm in diameter. Detection of NF-KB was performed by the Southwestern immunohistochemistry method. We evaluated immunohistochemical expression of survivin, prohibitin, TNFR1, p53, B- catenin, MMPs 2 and 9, VEGF, caspase 3 and method Tunnel. We did not observe immunohistochemical expression of NF-KB in 70% of cases of adenocarcinomas, in 72% of HG adenomas and 89% of lesions serrated; staining was positive in 66% and 56% of cases of LG adenoma and control, respectively. Expressions of survivin, cytoplasmic prohibitin, TNFR1, p53, MMPs 2 and 9 were increasing in adenoma-carcinoma sequence, without apparent modulation by NF-KB. Survivin suppressed action of caspase 3, except in BG adenomas and control, with low levels of apoptosis to the tunnel. Serrated lesions and control showed low expression of TNFR1 and cytoplasmic prohibitin, the absence of staining of p53 and MMPs2 and 9, except for one control. We identified nuclear staining of prohibitin in poorly differentiated adenocarcinomas, HG and LG adenomas. Expression of p53 was related to the grade of dysplasia in adenomas and deregulation of survivin.The expression of the cytoplasmic and nuclear B-catenin was observed in adenocarcinoma, HG and LG adenoma. Serrated lesions exhibited cytoplasmic expression in 44% of cases. Control group exhibited preserved expression of B-catenin. It was identified VEGF expression in adenocarcinomas, related to the loss of cellular differentiation, metastasis, not correlated with NF-KB. According to our results, we suggest that deregulation of catenin is possible responsible for the inhibition of NF-KB besides their participation in the deregulation of survivin with p53.Serrated lesions exhibited no evidence suggestive of inhibition of NF-KB by B-catenin. Survivin emerges as a potential therapeutic target in the treatment of CRC due to their anti-apoptotic properties, confirming previous studies.
336

Análise da expressão de receptores hormonais (androgênio, estrogênio alfa e beta) e da aromatase em carcinomas epidermóides de boca (CE) / Analysis of the expression of hormonal receptors (androgen, estrogen alpha and beta) and aromatase enzime in oral squamous cell carcinoma (OSCC)

Marocchio, Luciana Sassa 10 December 2010 (has links)
Das diversas neoplasias denominadas câncer de boca, mais de 95% tem o diagnóstico de carcinoma epidermóide (CE). O carcinoma epidermóide apresenta etiologia e patogênese complexas e não totalmente compreendidas determinando altos índices de morbidade e mortalidade. Por isso crescentes esforços têm sido empregados para a melhor compreensão dos eventos celulares, da susceptibilidade genética e dos fatores de risco que atuando em conjunto dão origem e atuam na progressão do carcinoma epidermóide de boca. Buscando novas facetas da carcinogênese oral e baseando-se no papel pró-carcinogênico que os hormônios esteróides desempenham nas neoplasias dos órgãos reprodutivos, alguns estudos passaram a avaliar o papel desses hormônios na patogênese e progressão do CE. O propósito deste trabalho foi avaliar a presença dos receptores de androgênio, estrogênio (alfa e beta) e da enzima aromatase em carcinomas epidermóides de boca (CE), através das técnicas de imuno-histoquímica, western-blotting e imunofluorescência, e comparar, com base no gênero (masculino e feminino), os resultados encontrados. Da amostra de CE utilizada, 30 eram pertencentes a pacientes do gênero feminino e 30 do masculino. Para as reações de Western blotting e imunofluorescência foram utilizadas duas linhagens celulares: OSCC9 e OSCC25, derivadas de CE de língua. Nas reações imunohistoquímicas, apesar de um número maior de casos negativos do que positivos, observou-se que o receptor de estrogênio beta foi o mais expresso, seguido pelo receptor de androgênio e aromatase. O receptor de estrogênio alfa apresentou menor imunoexpressão. Houve diferença estatisticamente significante entre os gêneros apenas na expressão dos receptores de androgênio. Os resultados obtidos pelo western blotting e imunofluorescência evidenciaram que as duas linhagens celulares utilizadas apresentaram receptores de estrogênio beta no núcleo, bem como, a presença da enzima aromatase com localização citoplasmática. Os receptores de androgênio foram observados no núcleo somente na linhagem OSCC9 enquanto que os receptores de estrogênio alfa não foram evidenciados em nenhuma das linhagens. Esses resultados sugerem que em alguns casos de CE possa existir contribuição hormonal na progressão da doença, evidenciando a necessidade da utilização desses marcadores nesse tipo de neoplasia. / Oral squamous cell carcinoma (OSCC) is the main type of oral cancer presenting complex and not completely understood pathogenesis. OSCC implies quite significant mortality and morbidity rates and in spite of the vast amount of research and the advances in the field of oncology and surgery, the overall survival remains largely unchanged. Therefore, the identification of new pathways involved in the mechanisms of carcinogenesis can bring knowledge to the control and advent of new treatments. The role of androgens and estrogens in several endocrine-related malignancies is well known. The successful use of these hormones antagonists in the treatment of these neoplasms has prompted researches to investigate the presence of hormones receptors in other tissues and tumor types. The aim of this study was to asses through immunohistochemistry, western blot and immunoflorescence assays the expression, genderrelated, of androgen, estrogen alpha and beta receptors and aromatase enzyme in cases of OSSC. A total of 60 cases of OSCC (30 from males and 30 from females) were retrieved and submitted to immunohistochemical assay. Two OSCC cell lines were used for western blot and immunoflurescence techniques: OSCC-9 and OSCC-25, originated from the tongue. Immunohistochemical staining demonstrated that estrogen beta and androgen receptors and aromatase enzyme, respectively, were more frequently expressed in OSCC. Estrogen alpha receptor had the lower immuno expression. Only androgen receptors presented differences statistically significant between genders. Western blotting and immunofluorescence analysis demonstrated that estrogen beta receptor was abundantly present in nuclear region of SCC9 and SCC25 cell lines, as well as aromatase protein, although its localization was cytoplasmatic. Androgen receptor was observed in the nucleus of SCC9 cell line and absent in the SCC25 cell line. On the other hand, estrogen alpha receptor was not detected either in western blot assay or in immunofluorescence. Even though these proteins presented a variable expression in OSCC, it is interesting to conduct more studies about them, since we could have more possibilities to predict and control oral squamous cell carcinoma.
337

Efeitos da síntese epitelial de serotonina sobre o desenvolvimento da carcinogênese de cólon / Effects of serotonin epithelial synthesis on the development of colon carcinogenesis

Gasparotto, Bianca 14 November 2017 (has links)
A serotonina (5-HT) é um neuro-hormônio com complexos efeitos em humanos e animais. Embora se acredite que a sinalização serotoninérgica promova o desenvolvimento de tumores de cólon, também tem sido observado que a redução dos níveis de 5-HT aumenta o risco de malignidades neste órgão. Assim, é necessário investigar como a síntese de 5-HT modula a carcinogênese de cólon. Esta hipótese será explorada em experimentos mecanísticos envolvendo a exposição ou não de camundongos a um agente carcinogênico (azoximetano). Estes experimentos revelaram que a exposição carcinogênica aumentou a síntese de 5-HT no cólon, uma vez que os processos de liberação e degradação de 5-HT foram reduzidos, enquanto que a sua síntese e recaptação aumentaram. Após 24 semanas da 1° exposição carcinogênica, a deleção da síntese de 5-HT promoveu a multiplicidade tumoral no cólon, enquanto que ao longo de 12 semanas ocorreu um aumento de lesões preneoplásicas e proliferação celular. É interessante que 72 hrs após a sexta e última exposição carcinogênica o número de criptas aberrantes foram detectadas reduzidas na ausência de 5-HT, o que ocorreu em conjunto com uma redução da atividade proliferativa, aumento de células apoptóticas, e maior dano de DNA. Finalmente, a 5-HT modulou mecanismos de reparo genômico. Concluímos que a síntese serotoninérgica parece ser um fator de proteção do cólon intestinal, que caso inibida facilitaria o desenvolvimento tumoral neste tecido. / Serotonin (5-HT) is a neurohormone with complex effects in humans and animals. Although serotonergic signaling has been suggested to promote the development of colon tumors, the reduction in 5-HT levels was reported to increase the risk of colon cancer. Here, we sought to investigate how 5-HT synthesis modulates colon carcinogenesis. This hypothesis was explored in mechanistic experiments that carcinogenically exposed or not mice to azoxymethane. It revealed that carcinogenic exposure increased the synthesis of 5-HT in the colon since 5-HT release and decay were inhibited, while its synthesis and reuptake are promoted. After 24 weeks from the first carcinogenic exposure, the deletion of 5-HT synthesis increased tumor multiplicity, while following 12 weeks it promoted the development of preneoplastic lesions, and cell proliferation in the colon. Interestingly, 72 hrs after the sixth and last carcinogenic exposures the number of aberrant crypts were detected reduced in the absence of 5-HT, which occurred together with a reduced proliferation, but increased apoptosis and DNA damage. Finally, 5-HT modulated genomic repair mechanisms. We conclude that serotonergic synthesis seems to be a protective factor of the intestinal colon, which inhibited case facilitates tumor development in this tissue.
338

Expressão da survivina em diferentes condições relacionadas à carcinogênese intra-bucal humana

Lima, Celina Faig [UNESP] 19 July 2010 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:30:59Z (GMT). No. of bitstreams: 0 Previous issue date: 2010-07-19Bitstream added on 2014-06-13T20:01:19Z : No. of bitstreams: 1 lima_cf_dr_sjc.pdf: 574864 bytes, checksum: cf6904339556fc2b74794049e1675fbe (MD5) / A survivina é uma proteína inibidora da apoptose que desempenha papel de controle no ciclo celular e no mecanismo de carcinogênese. Este trabalho teve como proposição verificar a correlação clinicopatológica da expressão da survivina nas diferentes condições relacionadas à carcinogênese intra-bucal humana, o que pode ser útil para destacar aspectos importantes das etapas da carcinogênese bucal. Foram constituídos três grupos, formados em parte por material citológico coletado de pacientes participantes do Programa Ambulatorial de Tratamento de Tabagismo do Instituto do Coração do Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo (INCOR-HCFMUSP); e por material que se encontra incluído em blocos de parafina no Laboratório de Patologia Bucal da Faculdade de Odontologia de São José dos Campos FOSJC – UNESP. O primeiro grupo foi constituído por material citológico obtido do bordo lateral lingual esquerdo e soalho bucal de 30 pacientes que fumavam mais de 20 cigarros/dia/10anos e que não apresentavam histórico de neoplasia bucal maligna, nem sinais clínicos visíveis no local avaliado; o segundo grupo foi constituído por amostras teciduais de 21 pacientes com lesões brancas clinicamente classificadas como leucoplasias. O terceiro grupo foi formado por 42 amostras teciduais de pacientes com diagnóstico de carcinoma epidermóide bucal. Os pacientes que foram submetidos à citologia esfoliativa foram examinados através de anamnese, exame clínico extra e intra -bucal. A citologia esfoliativa foi realizada com cytobrush para obtenção de duas lâminas de cada local selecionado. Após a realização da imunoistoquímica com anticorpo primário anti-survivina as lâminas foram analisadas qualitativamente através da microscopia óptica. Uma lâmina de assoalho e uma de língua foram coradas e avaliadas pelo método de Papanicolaou... / Survivin is an inhibitor of apoptosis protein that plays a role in cell cycle control and the mechanism of carcinogenesis. The aim of the present work was to study the clinicopathological correlation of survivin expression in different conditions related to intra-oral carcinogenesis. This may be useful to highlight important aspects of oral carcinogenesis steps. Three groups were analyzed. They were formed in part by cytological material collected from patients of Heart Institute’s Patient Center and the Smoking Cessation Program of the University Hospital, University of São Paulo Medical School (INCOR-HCFMUSP) and material of Laboratory of Oral Pathology, São José dos Campos Dental School. The first group consisted of cytologic material obtained from the left side of the tongue and mouth floor of 30 patients who smoked more than 20 cigarrettes/day/10years and had no history of malignant oral neoplasm or clinical signs at the site evaluated; the second group consisted of tissue samples from 21 patients with white lesions clinically classified as leukoplakia. The third group consisted of 42 tissue samples from patients diagnosed with oral squamous cell carcinoma. Patients who underwent exfoliative cytology were examined by medical history, extra and intra-oral clinical examination. The exfoliative cytology was performed using cytobrush to obtain two smears of each selected location. After performing the immunohistochemistry for anti-survivin the slides were analyzed qualitatively by light microscopy. One smear of mouth floor and tongue was stained and evaluated by the method of Papanicolaou. Statistical analysis was performed by Fisher's exact test, Mann-Whitney and X2. Survivin was positive in 100% of cytological material from the smokers, 85.7% of oral leukoplakia and 83.3% of oral squamous cell carcinoma. Fisher's exact test showed no association between the expression... (Complete abstract click electronic access below)
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Imunofenotipagem de lesões obtidas em carcinogênese quimicamente induzida por DMBA em glândulas salivares submandibulares e ratos (Rattus norvegicus) /

Mainenti, Pietro. January 2009 (has links)
Resumo: A carcinogênese química em glândulas salivares animais não se apresenta como um modelo novo de pesquisa. O uso de DMBA em glândulas submandibulares de ratos produz carcinomas e sarcomas, associados ou não. Apesar de bem estudada a histopatologia deste tipo de carcinogênese, pouco se sabe em relação a imunoistoquímica das neoplasias. Este estudo se propõe a revisar pesquisa pregressa realizada por Mainenti (2006), na tentativa de melhor entender a formação de tumores induzidos por DMBA. O estudo original diagnosticou lesões não neoplásicas, principalmente sialadenites, e tumores como carcinomas, carcinossarcomas e um caso de sarcoma. O presente trabalho fez uso de lâminas e material de estoque em formol. Foram comparadas as lâminas originais com novas lâminas coradas em hematoxilina e eosina. Para a pesquisa de fibras colágenas utilizou-se a coloração pelo método do tricrômico de Gomori. A imunoistoquímica foi realizada utilizando os seguintes anticorpos: AE1/AE3, vimentina, α-SMA, calponina, desmina, miogenina, S-100, CerbB-2 e EMA. Certas lesões, previamente diagnosticadas como sialadenites, foram reclassificadas como carcinomas. A imunoistoquímica foi positiva para os seguintes anticorpos: AE1/AE3 para neoplasia epitelial, vimentina para tecido conjuntivo e tumores mesenquimais, α-SMA e calponina para poucas células fusiformes pleomórficas no estroma dos carcinomas e nas neoplasias mesenquimais. Concluiu-se que a imunoistoquímica revelou diferenciação muito sugestiva de miofibroblastos no estroma dos carcinomas e miofibroblastos compondo o fibrossarcoma e os carcinosarcomas. Estas células produziram colágeno revelado pelo tricrômico de Gomori. O componente epitelial neoplásico foi sugerido como derivado de células luminais. / Abstract: The chemical carcinogenesis, addressed to animal salivary gland, is not a novel research. The use of DMBA in rat's submandibular salivary gland is known to produce neoplasms like sarcomas and carcinomas either intermingled or not. Despite of the good amount of information regarding DMBA carcinogenesis histopathology in rat's submandibular parenchyma, little is known about the immunohistochemistry in such tumors. We proposed a revision of a previous research conduced by Mainenti (2006), in attempt to better understand the neoplasm formation after DMBA. The original experiment disclosed non neoplastic lesions, mainly sialadenitis, and tumors like carcinomas, carcinosarcomas and one case of sarcoma. The present work used all the material from the first research like surgical specimens in formol and slides. We compared the previous hematoxylin and eosin slides with new ones. We also used Gomori's trichrome in order to disclose collagen fibers. The immunohistochemistry was performed using the following antibodies: AE1/AE3, vimentin, α-SMA, calponin, desmin, myogenin, S-100, CerbB-2 and EMA. Some previous lesions, presented as benign ones, were diagnosed as carcinomas. The immunohistochemistry was positive as shown: AE1/AE3 for epithelial neoplasm, vimentin for connective tissue in mesenchymal tumors, α-SMA and calponin for scarce pleomorphic fusiform cells in the stroma of the carcinomas and in the mesenchymal neoplasms. We concluded that the immunohistochemistry strongly suggested myofibroblast differentiation in the stroma of the carcinomas and myofibroblast cells related to the fibrosarcoma and carcinosarcomas. These cells produced collagen shown after Gomori's trichrome. The epithelial neoplasm component was suggested as derived from luminal cells. / Orientador: Luiz Eduardo Blumer Rosa / Coorientador: Yasmin Rodarte Carvalho / Banca: Luiz Eduardo Blumer Rosa / Banca: Rosilene Fernandes da Rocha / Banca: Fábio Daumas Nunes / Banca: Maria das Graças Afonso Miranda Chaves / Banca: Adriana Aigotti Haberbeck Brandão / Doutor
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O estudo do NF-KB e da Survivina na progressão do Câncer Colorretal / The study of NF-KB and survivin in the progression of colorectal cancer.

Mariângela Ottoboni Brunaldi 25 March 2013 (has links)
O câncer colorretal (CCR) é importante causa de morte no Brasil, representando a segunda causa de morbimortalidade por câncer nas regiões Sudeste e Sul. Foi uma das primeiras neoplasias malignas a ter modelo de carcinogênese identificado. Os objetivos deste trabalho foram avaliar a expressão do NF-KB e da survivina na progressão do CCR, sua relação com alvos moleculares envolvidos na sobrevivência celular [proibitina, fator de necrose tumoral (TNFR1), p53, B- catenina]; invasão (metaloproteinases 2 e 9 - MMP), angiogênese (fator de crescimento endotelial vascular VEGF) e apoptose (caspase 3 e método do Túnel). Trata-se de estudo retrospectivo baseado na análise histopatológica de dezoito casos de adenomas com displasia de alto (AG) e baixo grau (BG), respectivamente; dez casos de adenocarcinoma bem, moderado e pouco diferenciado, respectivamente, nove casos de lesões serrilhadas e nove biópsias colorretais (controle) selecionados aleatoriamente no Serviço de Patologia do Hospital das Clínicas da Faculdade de Medicina de Ribeirão Preto da Universidade de São Paulo, no período de 2000 a 2009. Foram construídos arranjos de matriz tecidual para representar os casos de adenocarcinomas e cinco casos de adenomas >1 cm de diâmetro. A detecção do NF-KB foi realizada pelo método de Southwestern imunoistoquímica. Avaliou-se a expressão imunoistoquímica da survivina, proibitina, TNFR1, p53, B-catenina, MMPs 2 e 9, VEGF, caspase 3 e Túnel. Não observamos expressão imunoistoquímica do NF-KB em 70% dos casos de adenocarcinomas, em 72% dos adenomas AG e em 89% das lesões serrilhadas; a marcação foi positiva em 66% e 56% dos casos de adenoma do BG e controle, respectivamente. Expressões da survivina, proibitina citoplasmática, TNFR1, p53, MMP 2 e 9 foram crescentes na seqüência adenoma-carcinoma, sem aparente modulação pelo NF-KB. A survivina suprimiu ação da caspase 3, exceto nos adenomas BG e controle, com baixos níveis de apoptose ao túnel. Lesões serrilhadas e controle apresentaram baixa expressão do TNFR1 e da proibitina citoplasmática, ausência de marcação da p53 e MMPs 2 e 9, exceto um caso controle. Identificou-se marcação nuclear da proibitina nos adenocarcinomas pouco diferenciados, adenomas AG e BG. A expressão da p53 relacionou-se ao grau de displasia nos adenomas e à desregulação da survivina. Observou-se expressão citoplasmática e nuclear da B- catenina nos adenocarcinomas, adenomas AG e BG. As lesões serrilhadas exibiram expressão citoplasmática em 44% dos casos. O grupo controle exibiu expressão preservada da B-catenina. Identificou-se expressão do VEGF nos adenocarcinomas, relacionada à perda de diferenciação celular, presença de metástases, não correlacionada ao NF-KB. Com base nos nossos resultados, sugerimos a desregulação da B- catenina como possível responsável pela inibição do NF-KB; além de sua participação na desregulação da survivina juntamente com a p53. As lesões serrilhadas não exibiram indícios sugestivos de inibição do NF- KB pela B-catenina.A survivina, devido propriedades anti-apoptóticas, emerge como potencial alvo terapêutico no tratamento do CCR, confirmando estudos anteriores. / Colorectal cancer (CRC) is an important cause of death in Brazil, representing the second leading cause of cancer mortality in the Southeast and South. It was among the first malignancies that have the carcinogenesis model identified.The aim of this study was to evaluate the expression of NF-KB and survivin in the progression of CRC, its relationship with molecular targets involved in cell survival [prohibitin, tumor necrosis factor (TNFR1), p53,B-catenina], invasion (metalloproteinases 2 and 9 - MMP), angiogenesis (vascular endothelial growth factor VEGF) and apoptosis (caspase 3 and method Tunnel). This is a retrospective study based on the histopathological analyses of eighteen cases of high- (HG) and low- grade dysplastic (LG) adenomas, respectively; ten cases of adenocarcinoma well, moderately and poorly differentiated, respectively, nine cases of serrated lesions e nine biopsies (control); randomly selected in the Pathology Service of the University Hospital of the Faculty of Medicine of Ribeirão Preto, University of São Paulo from 2000 to 2009. Tissue microarray were constructed to represent the cases of adenocarcinomas and five cases of adenomas > 1cm in diameter. Detection of NF-KB was performed by the Southwestern immunohistochemistry method. We evaluated immunohistochemical expression of survivin, prohibitin, TNFR1, p53, B- catenin, MMPs 2 and 9, VEGF, caspase 3 and method Tunnel. We did not observe immunohistochemical expression of NF-KB in 70% of cases of adenocarcinomas, in 72% of HG adenomas and 89% of lesions serrated; staining was positive in 66% and 56% of cases of LG adenoma and control, respectively. Expressions of survivin, cytoplasmic prohibitin, TNFR1, p53, MMPs 2 and 9 were increasing in adenoma-carcinoma sequence, without apparent modulation by NF-KB. Survivin suppressed action of caspase 3, except in BG adenomas and control, with low levels of apoptosis to the tunnel. Serrated lesions and control showed low expression of TNFR1 and cytoplasmic prohibitin, the absence of staining of p53 and MMPs2 and 9, except for one control. We identified nuclear staining of prohibitin in poorly differentiated adenocarcinomas, HG and LG adenomas. Expression of p53 was related to the grade of dysplasia in adenomas and deregulation of survivin.The expression of the cytoplasmic and nuclear B-catenin was observed in adenocarcinoma, HG and LG adenoma. Serrated lesions exhibited cytoplasmic expression in 44% of cases. Control group exhibited preserved expression of B-catenin. It was identified VEGF expression in adenocarcinomas, related to the loss of cellular differentiation, metastasis, not correlated with NF-KB. According to our results, we suggest that deregulation of catenin is possible responsible for the inhibition of NF-KB besides their participation in the deregulation of survivin with p53.Serrated lesions exhibited no evidence suggestive of inhibition of NF-KB by B-catenin. Survivin emerges as a potential therapeutic target in the treatment of CRC due to their anti-apoptotic properties, confirming previous studies.

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