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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

The combination of pan-ErbB tyrosine kinase inhibitor CI-1033 and lovastatin: A potential novel therapeutic approach in squamous cell carcinoma of the head and neck

Guimond, Tanya January 2011 (has links)
The ErbB family of receptors are key regulators of growth, differentiation, migration and survival of epithelial cells. CI-1033 is an irreversible pan-ErbB tyrosine kinase inhibitor that has the ability to inhibit EGFR function but has shown limited therapeutic efficacy. Lovastatin targets the activity of HMG-CoA reductase, the rate-limiting step in the mevalonate pathway. In this study, the ability of lovastatin to potentiate the cytotoxic effects of CI-1033 was evaluated. The combination of lovastatin and CI-1033 exhibited some cooperative cytotoxic activity in a squamous cell carcinoma–derived cell line. This combination resulted in enhanced cell death by induction of a potent apoptotic response. Furthermore, this drug combination inhibited EGF-induced EGFR autophosphorylation and activation of the downstream signaling effectors, ERK and AKT. These findings suggest that combining lovastatin and tyrosine kinase inhibitors may represent a novel combinational therapeutic approach in squamous cell carcinoma of the head and neck.
72

Role onkogenu erbB-2 v biologii rakovinných kmenových buněk / The role of erbB-2 oncogene in the biology of cancer stem-like cells

Prokopová, Kateřina January 2010 (has links)
Recent studies indicate the existence of a subpopulation of cells within tumours with stem cell-like characteristics. These "cancer stem-like cells" (CSCs) are relatively resistant to established therapies, usually targeting differentiated and fast proliferating cells. Therefore, CSCs may be a reason for the relapse of neoplastic diseases. CSCs can be characterised by a specific gene expression profile and deregulated signalling pathways. Of these, upregulation of the erbB-2 (HER2) receptor, a hallmark of ~25-30% breast cancer patients, is related to dismal prognosis, elevated proliferation potential and resistance to chemotherapy. Recent evidence has suggested that upregulation of erbB-2 leads to increase in the pool of CSCs. In our study we used mammospheres, cells grown in the absence of serum, an in vitro model of breast CSCs, which were prepared by "weaning" breast cancer MCF7 cells to a special medium. These cells were CD44high and showed increased expression of ABCG-2, Sox-2, Vimentin as well as high levels of erbB-2. Next, we prepared a stable line of MCF7 cells with low levels of erbB-2 by shRNA. ErbB-2low cells were characterised for expression of set of CSCs markers and tested for tumour forming efficacy in nude mice using ultrasound imaging. Keywords Cancer stem-like cells, erbB-2,...
73

The Epidermal Growth Factor Receptor (EGFR) Is Proteolytically Modified by the Matriptase-Prostasin Serine Protease Cascade in Cultured Epithelial Cells

Chen, Mengqian, Chen, Li Mei, Lin, Chen Yong, Chai, Karl X. 01 May 2008 (has links)
Prostasin is expressed at the apical surface of normal epithelial cells and suppresses in vitro invasion of cancer cells. Prostasin re-expression in the PC-3 prostate carcinoma cells down-regulated the epidermal growth factor receptor (EGFR) protein expression and EGF-induced phosphorylation of the extracellular signal-regulated kinases (Erk1/2). We report here that prostasin and its activating enzyme matriptase are capable of inducing proteolytic cleavages in the EGFR extracellular domain (ECD) when co-expressed in the FT-293 cells, generating two amino-terminally truncated fragments EGFR135 and EGFR110, at 135 and 110 kDa. Prostasin's role in EGFR cleavage is dependent on the serine active-site but not the GPI-anchor. The modifications of EGFR were confirmed to be on the primary structure by deglycosylation. EGFR135 and EGFR110 are not responsive to EGF stimulation, indicating loss of the ligand-binding domains. EGFR110 is constitutively phosphorylated and in its presence Erk1/2 phosphorylation is increased in the absence of EGF. The protease-induced EGFR cleavages are not dependent on EGFR phosphorylation. The EGFR ECD proteolytic modification by matriptase-prostasin is also observed in the BEAS-2B normal lung epithelial cells, the BPH-1 benign prostate hyperplasia and the MDA-MB-231 breast cancer cell lines; and represents a novel mechanism for epithelial cells to modulate EGF-EGFR signaling.
74

Inhibition of HER Receptors Reveals Distinct Mechanisms of Compensatory Upregulation of Other HER Family Members: Basis for Acquired Resistance and for Combination Therapy

Gutsch, Daniela, Jenke, Robert, Büch, Thomas, Aigner, Achim 03 May 2023 (has links)
Overexpression of members of the HER/erbB transmembrane tyrosine kinase family like HER2/erbB2/neu is associated with various cancers. Some heterodimers, especially HER2/HER3 heterodimers, are particularly potent inducers of oncogenic signaling. Still, from a clinical viewpoint their inhibition has yielded only moderate success so far, despite promising data from cell cultures. This suggests acquired resistance upon inhibitor therapy as one putative issue, requiring further studies in cell culture also aiming at rational combination therapies. In this paper, we demonstrate in ovarian carcinoma cells that the RNAi-mediated single knockdown of HER2 or HER3 leads to the rapid counter-upregulation of the respective other HER family member, thus providing a rational basis for combinatorial inhibition. Concomitantly, combined knockdown of HER2/HER3 exerts stronger anti-tumor effects as compared to single inhibition. In a tumor cell line xenograft mouse model, therapeutic intervention with nanoscale complexes based on polyethylenimine (PEI) for siRNA delivery, again reveals HER3 upregulation upon HER2 single knockdown and a therapeutic benefit from combination therapy. On the mechanistic side, we demonstrate that HER2 knockdown or inhibition reduces miR-143 levels with subsequent de-repression of HER3 expression, and validates HER3 as a direct target of miR-143. HER3 knockdown or inhibition, in turn, increases HER2 expression through the upregulation of the transcriptional regulator SATB1. These counter-upregulation processes of HER family members are thus based on distinct molecular mechanisms and may provide the basis for the rational combination of inhibitors.
75

Genetische Analyse entwicklungsbiologischer Funktionen des Neuregulin-1/ErbB Signalsystems

Britsch, Stefan 10 November 2004 (has links)
Neureguline (NDF, Heregulin, GGF ARIA, oder SMDF) sind EGF-ähnliche, extrazelluläre Signalmoleküle, die mit transmembranären Tyrosinkinaserezeptoren der ErbB-Familie interagieren. Neuregulin-1/ErbB Signale steuern während der Embryonalentwicklung und im adulten Organismus vielfältige zelluläre Prozesse, wie z. B. Proliferation, Migration und Differenzierung. In der vorliegenden Arbeit wurde die Rolle des Neuregulin-1/ErbB Signalsystems in der Entwicklung von Neuralleistenzellen und sich daraus entwickelnden Komponenten des peripheren Nervensystems (sympathisches Nervensystem und periphere Glia) untersucht. Neuregulin-1 Signale werden in Neuralleistenzellen und ihren Gliaderivaten durch ErbB2/ErbB3 Rezeptor-Heterodimere übertragen. Mit Hilfe von Mäusen mit gezielter Mutation (knock-out) des Neuregulin-1, ErbB2 oder ErbB3 Gens wurde gezeigt, daß Neuregulin-1/ErbB2/3 Signale die Migration sympathogener Neuralleistenzellen steuern. Mutante Tiere entwickeln daher eine hochgradige Hypoplasie des sympathischen Nervensystems. Neuregulin-1 Signale kontrollieren darüber hinaus die Entwicklung von Schwann Zellen. Die Unterbrechung des Neuregulin-1/ErbB2/3 Signalwegs in mutanten Mäusen führt zum Verlust von Schwann Zellen während der Embryogenese. Es wurde außerdem gezeigt, daß der Transkriptionsfaktor Sox10 die Expression von ErbB3 in Neuralleistenzellen kontrolliert. Sox10 und ErbB3 Mutanten besitzen daher übereinstimmende Defekte in der Neuralleistenzellentwicklung. Neben den ErbB3-abhängigen Funktionen von Sox10 wurde eine ErbB3-unabhängige Schlüsselfunktion von Sox10 bei der Differenzierung von Neuralleistenzellen zu peripherer Glia identifiziert. Das Neuregulin-1/ErbB2/3 Signalsystem und der Transkriptionsfaktor Sox10 besitzen also gemeinsam zentrale Funktionen in der Entwicklung peripherer Glia, steuern diesen Prozess aber über unterschiedliche Mechanismen und während unterschiedlicher Entwicklungsphasen. Sox10, ErbB2 und ErbB3 mutante Mäuse entwickeln neben dem Verlust von Schwann Zellen eine sekundäre Degeneration begleitender sensorischer und motorischer Neurone. Dies zeigt, daß periphere Glia Signale generiert, die essentiell sind für Integrität und Überleben begleitender Neurone. / Neuregulins (NDF, heregulin, GGF ARIA, or SMDF) are EGF-like growth and differentiation factors that signal through tyrosine kinase receptors of the erbB family. The neuregulin-1 proteins and their receptors play essential roles during embryonic development and in the adult. Functions of the neuregulin/erbB signaling system in developing neural crest cells and their derivatives (sympathetic nervous system, peripheral glial cells) were analyzed in mice with targeted mutations in the erbB2, erbB3, or neuregulin-1 genes. All three mutations cause severe hypoplasia of the primary sympathetic ganglion chain, and migration of sympathogenic neural crest cells to their target sites, where they differentiate into sympathetic neurons, depends on neuregulin-1 and its receptors. Neuregulin-1 signals are also essential for the development of Schwann cells. As a consequence, mice with targeted mutations in the neuregulin-1/erbB signaling system completely lack Schwann cells. Moreover, the HMG-box transcription factor sox10 is shown to control expression of erbB3 in neural crest cells. In accordance, sox10 and erbB3 mutant mice share phenotypes in the developing neural crest. Additionally, a novel, erbB3-independent developmental function of sox10 was identified: Sox10 is a key regulator for glial fate determination in undifferentiated neural crest cells. Thus, the transcription factor sox10 and the neuregulin-1/erbB signalling system both serve critical functions during development of peripheral glial cells. However, they act via different cellular mechanisms and during different developmental stages. At later developmental stages lack of peripheral glial cells in sox10, erbB2 and erbB3 mutant mice results in a severe degeneration of sensory and motor neurons. The comparison of the mutant phenotypes demonstrates, that peripheral glial cells generate essential signals for the survival and maintenance of accompanying neurons.
76

Estudo do perfilamento gênico tumoral e de marcadores de doença residual mínima (CK19 e c-ErbB-2) através de RT-PCR quantitativo na fração mononuclear do sangue periférico em pacientes com câncer de mama durante o tratamento / Study of tumor gene profiling and minimal residual disease markers (CK19 and c-ErbB-2) by quantitative RT-PCR in peripheral blood mononuclear fraction in patients with breast cancer during chemotherapy

Kuniyoshi, Renata Kelly 13 November 2013 (has links)
INTRODUÇÃO: De acordo com a estimativa de 2012 do INCA, eram esperados 52.680 novos casos de câncer de mama no Brasil, com um risco estimado de 52 casos a cada 100 mil mulheres. Estes dados mostram a necessidade da identificação de biomarcadores efetivos para rastreamento precoce e seguimento destas mulheres durante seu tratamento. Neste trabalho, para a avaliação de potenciais biomarcadores desta doença, foi idealizado um modelo laboratorial específico que avalie tanto a capacidade de um dado biomarcador rastrear um tumor inicial de mama, bem como testar o seu potencial valor para o seguimento de mulheres já diagnosticadas durante seu tratamento. Este modelo baseia-se na avaliação de células tumorais circulantes e perfilamento gênico tumoral. MÉTODOS: Amostras biológicas (sangue periférico e tumor) de 167 pacientes diagnosticadas com carcinoma mamário estadios I, II e III com indicação de quimioterapia adjuvante para: a) avaliação da presença de células tumorais circulantes através da expressão de CK19 e HER2 na Fração Mononuclear do Sangue Periférico (FMNSP) por RT-PCR quantitativo e b) perfilamento gênico tumoral através da análise da expressão de 21 genes relacionados a importantes processos de carcinogênese mamária em amostras de tecido parafinado por ensaio multiplex de RT-PCR quantitativo utilizando o sistema Plexor®. RESULTADOS: Foi observada uma correlação significativa entre CK19 e HER2 na primeira coleta e queda da concentração de HER2 no SP durante o tratamento; porém, não foi percebida queda significativa do CK19 ao longo do estudo. A expressão de HER2 na segunda coleta de pacientes positivas para HER2 na primeira coleta tendeu a se correlacionar significativamente com um pior Intervalo Livre de Doença (ILD). Através da padronização da pontuação em quartis das análises realizadas em multiplex pelo sistema Plexor, foi percebido que o quartil superior apresentava ILD significativa pior do que a de pacientes nos demais quartis. Também foi observada uma estratificação do estadio clínico II em pior ou melhor prognóstico de acordo com o quartil de pontuação do teste de perfilamento proposto neste estudo; além disso, verificou-se que pacientes submetidas a tratamento neoadjuvante com pontuações inferiores tenderam a responder melhor à quimioterapia. CONCLUSÃO: Pelas características do comportamento evolutivo no presente estudo, HER2 parece ser melhor como possível biomarcador de células tumorais circulantes do que o CK-19. Até o presente momento do seguimento das pacientes incluídas neste estudo, não foi possível criar um modelo com diversas variáveis para prever o prognóstico de pacientes com câncer de mama. Isto ocorreu principalmente pelas características preditivas prognósticas superiores do perfilamento genético do tumor que desloca fatores de prognóstico tais como células circulantes e estadio clínico, expressão hormonal do tumor e idade de um modelo multivariado. Por outro lado, foi padronizada uma tecnologia genômica complexa que poderá viabilizar seu uso para a população se estudos posteriores confirmarem seu valor em outras coortes de pacientes com câncer de mama / BACKGROUND: According to the estimate of 2012 INCA, were expected 52,680 cases of breast cancer in Brazil, with an estimated risk of 52 cases per 100 000 women. These data show the need for effective identification of biomarkers for early screening and follow-up of these women during their treatment. In this work, for the evaluation of potential biomarkers of this disease, a model laboratory was designed to evaluate both the specific capacity of a given biomarker trace an initial breast tumor, as well as test its potential value for the follow-up of women already diagnosed during their treatment. This model was based on the evaluation of circulating tumor cells and tumor gene profiling. METHODS: Biological samples (peripheral blood and tumor) of 167 patients diagnosed with breast cancer stages I, II and III with an indication for adjuvant chemotherapy: a) to evaluate the presence of circulating tumor cells through the expression of HER2 and CK19 in Peripheral Blood Mononuclear fraction (PBMN) by quantitative RT-PCR and b) tumor profiling gene by analyzing the expression of 21 genes related to important processes of mammary carcinogenesis in paraffinized tissue samples by multiplex assay for quantitative RT-PCR using the Plexor ® System. RESULTS: Was observed a significant correlation between HER2 and CK19 in the first collection and decrease in concentration of HER2 in PB during the treatment, but were not perceived significant decrease of CK19 along the study. The expression of HER2 in the second collection of patients positive for HER2 in the first test tended to correlate with a significantly worse disease-free interval (DFI). Through standardization of the scores in quartiles of the analyzes performed at multiplex Plexor system was seen that the upper quartile ILD had significantly worse than patients in the other quartiles. Also stratification was observed in clinical stage II in better or worse prognosis according to quartiles of test score profiling proposed in this study, in addition, it was found that patients submitted to neoadjuvant treatment with lower scores tended to better respond to chemotherapy. CONCLUSION: HER2 seems to be better as possible biomarker of circulating tumor cells than the CK-19. So far the monitoring of patients included in this study, it was not possible to create a model with multiple variables to predict the prognosis of patients with breast cancer. This occurred primarily due to the characteristics predictive prognostic upper genetic profiling of tumor that displaces prognostic factors such as circulating cells and clinical stage, tumor hormone expression and age in a multivariate model. In the other hand, was standardized complex genomic technology that may enable their use for the population if further studies confirm its value in other cohorts of patients with breast cancer
77

Estudo do perfilamento gênico tumoral e de marcadores de doença residual mínima (CK19 e c-ErbB-2) através de RT-PCR quantitativo na fração mononuclear do sangue periférico em pacientes com câncer de mama durante o tratamento / Study of tumor gene profiling and minimal residual disease markers (CK19 and c-ErbB-2) by quantitative RT-PCR in peripheral blood mononuclear fraction in patients with breast cancer during chemotherapy

Renata Kelly Kuniyoshi 13 November 2013 (has links)
INTRODUÇÃO: De acordo com a estimativa de 2012 do INCA, eram esperados 52.680 novos casos de câncer de mama no Brasil, com um risco estimado de 52 casos a cada 100 mil mulheres. Estes dados mostram a necessidade da identificação de biomarcadores efetivos para rastreamento precoce e seguimento destas mulheres durante seu tratamento. Neste trabalho, para a avaliação de potenciais biomarcadores desta doença, foi idealizado um modelo laboratorial específico que avalie tanto a capacidade de um dado biomarcador rastrear um tumor inicial de mama, bem como testar o seu potencial valor para o seguimento de mulheres já diagnosticadas durante seu tratamento. Este modelo baseia-se na avaliação de células tumorais circulantes e perfilamento gênico tumoral. MÉTODOS: Amostras biológicas (sangue periférico e tumor) de 167 pacientes diagnosticadas com carcinoma mamário estadios I, II e III com indicação de quimioterapia adjuvante para: a) avaliação da presença de células tumorais circulantes através da expressão de CK19 e HER2 na Fração Mononuclear do Sangue Periférico (FMNSP) por RT-PCR quantitativo e b) perfilamento gênico tumoral através da análise da expressão de 21 genes relacionados a importantes processos de carcinogênese mamária em amostras de tecido parafinado por ensaio multiplex de RT-PCR quantitativo utilizando o sistema Plexor®. RESULTADOS: Foi observada uma correlação significativa entre CK19 e HER2 na primeira coleta e queda da concentração de HER2 no SP durante o tratamento; porém, não foi percebida queda significativa do CK19 ao longo do estudo. A expressão de HER2 na segunda coleta de pacientes positivas para HER2 na primeira coleta tendeu a se correlacionar significativamente com um pior Intervalo Livre de Doença (ILD). Através da padronização da pontuação em quartis das análises realizadas em multiplex pelo sistema Plexor, foi percebido que o quartil superior apresentava ILD significativa pior do que a de pacientes nos demais quartis. Também foi observada uma estratificação do estadio clínico II em pior ou melhor prognóstico de acordo com o quartil de pontuação do teste de perfilamento proposto neste estudo; além disso, verificou-se que pacientes submetidas a tratamento neoadjuvante com pontuações inferiores tenderam a responder melhor à quimioterapia. CONCLUSÃO: Pelas características do comportamento evolutivo no presente estudo, HER2 parece ser melhor como possível biomarcador de células tumorais circulantes do que o CK-19. Até o presente momento do seguimento das pacientes incluídas neste estudo, não foi possível criar um modelo com diversas variáveis para prever o prognóstico de pacientes com câncer de mama. Isto ocorreu principalmente pelas características preditivas prognósticas superiores do perfilamento genético do tumor que desloca fatores de prognóstico tais como células circulantes e estadio clínico, expressão hormonal do tumor e idade de um modelo multivariado. Por outro lado, foi padronizada uma tecnologia genômica complexa que poderá viabilizar seu uso para a população se estudos posteriores confirmarem seu valor em outras coortes de pacientes com câncer de mama / BACKGROUND: According to the estimate of 2012 INCA, were expected 52,680 cases of breast cancer in Brazil, with an estimated risk of 52 cases per 100 000 women. These data show the need for effective identification of biomarkers for early screening and follow-up of these women during their treatment. In this work, for the evaluation of potential biomarkers of this disease, a model laboratory was designed to evaluate both the specific capacity of a given biomarker trace an initial breast tumor, as well as test its potential value for the follow-up of women already diagnosed during their treatment. This model was based on the evaluation of circulating tumor cells and tumor gene profiling. METHODS: Biological samples (peripheral blood and tumor) of 167 patients diagnosed with breast cancer stages I, II and III with an indication for adjuvant chemotherapy: a) to evaluate the presence of circulating tumor cells through the expression of HER2 and CK19 in Peripheral Blood Mononuclear fraction (PBMN) by quantitative RT-PCR and b) tumor profiling gene by analyzing the expression of 21 genes related to important processes of mammary carcinogenesis in paraffinized tissue samples by multiplex assay for quantitative RT-PCR using the Plexor ® System. RESULTS: Was observed a significant correlation between HER2 and CK19 in the first collection and decrease in concentration of HER2 in PB during the treatment, but were not perceived significant decrease of CK19 along the study. The expression of HER2 in the second collection of patients positive for HER2 in the first test tended to correlate with a significantly worse disease-free interval (DFI). Through standardization of the scores in quartiles of the analyzes performed at multiplex Plexor system was seen that the upper quartile ILD had significantly worse than patients in the other quartiles. Also stratification was observed in clinical stage II in better or worse prognosis according to quartiles of test score profiling proposed in this study, in addition, it was found that patients submitted to neoadjuvant treatment with lower scores tended to better respond to chemotherapy. CONCLUSION: HER2 seems to be better as possible biomarker of circulating tumor cells than the CK-19. So far the monitoring of patients included in this study, it was not possible to create a model with multiple variables to predict the prognosis of patients with breast cancer. This occurred primarily due to the characteristics predictive prognostic upper genetic profiling of tumor that displaces prognostic factors such as circulating cells and clinical stage, tumor hormone expression and age in a multivariate model. In the other hand, was standardized complex genomic technology that may enable their use for the population if further studies confirm its value in other cohorts of patients with breast cancer
78

Analise imunoistoquimica de proteinas relacionadas ao ciclo celular (p53, Ki-67, bcl-2 e c-erbB-2) na transformação maligna do adenoma plenomorfico de glandula salivar / Immunohistochemical analysis of cel-cycle related proteins (p53, Ki-67, bcl-2 and c-erbB-2) in the malignant transformation of pleomorphic adenoma of salivary glands

Freitas, Leandro Luiz Lopes de 03 September 2006 (has links)
Orientador: Albina Messias de Almeida Milani Altemani / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Ciencias Medicas / Made available in DSpace on 2018-08-06T19:08:01Z (GMT). No. of bitstreams: 1 Freitas_LeandroLuizLopesde_D.pdf: 4064664 bytes, checksum: d04222e584211904229193f280c217a9 (MD5) Previous issue date: 2006 / Resumo: O adenoma pleomórfico (AP) é a neoplasia mais freqüente das glândulas salivares e o carcinoma ex-adenoma pleomórfico (CXAP) é a sua forma de transformação maligna mais comum. Os trabalhos da literatura com séries exclusivas de CXAP são poucos e englobam, em sua maioria, carcinomas já em estádios avançados. Raros são os estudos realizados exclusivamente com tumores que apresentam os dois componentes (benigno e maligno) e em fases iniciais de malignização. Alterações nos genes p53 e c-erbB-2 parecem ser as principais vias envolvidas nesta transformação. Estas proteínas, além do marcador de proliferação celular Ki-67, podem ser importantes critérios no diagnóstico do CXAP, especialmente em sua fase precoce. O objetivo deste trabalho foi avaliar retrospectivamente a expressão imunoistoquímica de marcadores celulares (p53, c-erbB-2, Ki-67 e bcl-2, uma proteína antiapoptótica) em CXAP em diferentes fases de malignização (4 intracapsulares, 4 minimamente invasivos e 7 francamente invasivos), nas áreas benignas e malignas e em AP que não sofreram malignização (17 casos - grupo controle). A parótida foi a glândula mais acometida em ambos os grupos (CXAP 53%, grupo controle 88%), envolvendo mais mulheres que homens. A idade média dos pacientes com CXAP em qualquer fase evolutiva (63,3 anos) foi maior que no grupo controle (35,6 anos). A proteína p53 foi mais expressa nas áreas malignas (em média 35,71% nos CXAP precoces e 8,11% nos CXAP francamente invasivos, versus 12,76% e 4,58% nas áreas benignas, respectivamente) e principalmente em células luminais, enquanto os menores valores foram encontrados no grupo controle (1,71%). Fato semelhante ocorreu com o índice mitótico e a expressão de Ki-67. A expressão de c-erbB-2 foi observada quase que exclusivamente em células malignas com diferenciação luminal. A proteína bcl-2 teve positividade fraca e focal. Concluímos que as proteínas p53 e c-erbB-2 parecem estar envolvidas na transformação maligna do AP, já em fases precoces, sendo critérios mais objetivos do que a simples avaliação morfológica para o diagnóstico dos CXAP intracapsulares / Abstract: Pleomorphic adenoma (PA) is the commonest salivary gland tumor, and carcinoma ex pleomorphic adenoma (CXPA) is its most frequent malignant counterpart. There are few studies centering on CXPA only and most have been performed in frankly invasive carcinomas. Series of CXPA containing both morphological components (adenoma and carcinoma) at an early stage of carcinomatous transformation are extremely rare. p53 and c-erbB-2 appear to be the most important genes involved in this malignant change. These proteins, and the proliferative index marker Ki-67, could be valuable criteria for diagnosis of CXPA, specially at an early stage. The aim of this study was to assess retrospectively the expression of cell markers (p53, c-erbB-2, Ki-67 and bcl-2, an antiapoptotic protein) in CXPA in different phases of malignant progression (4 intracapsular, 4 minimally invasive and 7 frankly invasive), in benign and malignant areas and in PA without malignant transformation (17 cases - control group). The parotid was the most frequently involved gland in both groups (CXPA: 53%, control group: 88%), and women were more affected than men. The average age in the CXPA group (63.3 years) at any stage was higher than in the control group (35.6 years). p53 expression was highest in malignant areas (mean 35.71% in early CXPA and 8.11% in frankly invasive CXPA, versus 12.76% and 4.58% in benign areas, respectively) and mainly in luminal cells, while the lowest values (1.71%) occurred in the control group. Similar findings were obtained with the mitotic index and Ki-67 expression. c-erbB-2 positivity was observed almost exclusively in malignant cells of the luminal type. bcl-2 expression was weak and focal. In conclusion, both p53 and c-erbB-2 proteins appear to be involved in malignization of PA since an early stage, thus providing criteria more objetive than simple morphological evaluation for diagnosis of intracapsular CXPA / Doutorado / Anatomia Patologica / Doutor em Ciências Médicas
79

Sobrevida e fatores associados em pacientes com câncer de mama, com diagnóstico entre 2003 e 2005 no munícipio de Juiz de Fora – Minas Gerais

Cintra, Jane Rocha Duarte 23 March 2012 (has links)
Submitted by Renata Lopes (renatasil82@gmail.com) on 2016-07-07T19:52:24Z No. of bitstreams: 1 janerochaduartecintra.pdf: 2932380 bytes, checksum: 42ad605d16a81a90bf6a3c42a06ea6b4 (MD5) / Approved for entry into archive by Adriana Oliveira (adriana.oliveira@ufjf.edu.br) on 2016-07-08T13:22:29Z (GMT) No. of bitstreams: 1 janerochaduartecintra.pdf: 2932380 bytes, checksum: 42ad605d16a81a90bf6a3c42a06ea6b4 (MD5) / Made available in DSpace on 2016-07-08T13:22:29Z (GMT). No. of bitstreams: 1 janerochaduartecintra.pdf: 2932380 bytes, checksum: 42ad605d16a81a90bf6a3c42a06ea6b4 (MD5) Previous issue date: 2012-03-23 / Objetivo: Analisar as taxas de sobrevida de cinco anos e os principais fatores associados ao perfil imunohistoquímico, em mulheres com câncer de mama. Métodos: A população foi composta a partir de coorte hospitalar formada por mulheres com diagnóstico de câncer de mama efetuado entre 2003 e 2005 (n=563) e atendidas em centro de referência em assistência oncológica de Juiz de Fora/MG. A data do diagnóstico histopatológico da doença foi considerada como início do tempo de sobrevida e a data do óbito pela doença foi considerada como o evento adverso. Foram censuradas as mulheres que permaneceram vivas até dezembro de 2010, data final do seguimento. Para aquelas que interromperam o seguimento, a data da censura foi referente ao último acompanhamento no registro médico. As curvas de sobrevida foram estimadas pelo método de Kaplan-Meier e o modelo de riscos proporcionais de Cox foi utilizado para a avaliação prognóstica. Resultados: A idade média das pacientes foi de 58,1 anos, sendo a maioria das pacientes (81,1%) da raça branca e pós-menopausa (66,8%). Os estádios clínicos predominantes foram o II (36,7%) e III (25,3%). Os subtipos mais frequentes foram os luminais A (n=295 casos – 52,4%) e os casos com perfil desconhecido (n=107 - 19%). A função de sobrevida específica para o câncer de mama, no período de cinco anos, foi de 79,9%. Entre as principais características associadas com uma melhor sobrevida não ajustada, na população de estudo, destacaram-se: subtipos imunohistoquímicos luminais (A e B) (p<0,0001), raça branca (p<0,0001), tamanho do tumor ≤ 2,0cm (p<0,0001), ausência de comprometimento linfonodal (p<0,0001), estádios mais precoces da doença (p<0,0001), realização de tratamento sistêmico (p=0,01) e uso de hormonioterapia (p<0,0001). Os principais fatores prognósticos associados à pior sobrevida foram: subtipos triplo negativo (p<0,001), HER2 superexpresso (p=0,01) e perfil imunohistoquímico desconhecido (p=0,01); raça não branca (p=0,02); doença avançada (estágio III e IV – p<0,001); tratamento sistêmico não realizado (p=0,009) e não utilização de quimioterapia de 1ª linha (p=0,09). Conclusão: Esta pesquisa possibilitou uma melhor caracterização do perfil imunohistoquímico e da sobrevida de pacientes com câncer de mama. / Purpose: Analyze the 5-year breast cancer specific-survival rate and according to the immunohistochemical profile of women diagnosed with breast cancer. Methods: The population was composed from a hospital-based cohort of all women diagnosed with breast cancer between 2003 and 2005 (n= 563), and treated at cancer care reference center in the city of Juiz de Fora/MG, Brazil. Survival time was counted from the date of the histopathological diagnosis and the date of death due to breast cancer was considered the adverse event. Women alive until December 2010, the final date of the follow-up, were censored. For those who interrupt treatment, censor date was the last follow-up in the medical records. Kaplan-Meier survival curves were estimated, and multivariate analysis was performed by the Cox proporciona hazard model. Results: Mean age was 58,05 years, and the majority were white skin color (81,1%) and postmenopausal (66,8%). Clinical Stages II (36,7%) and III (25,3%) predominated. The most common subtypes were luminal A (n= 295 cases – 52,4%) and cases with unknown profile (n= 107 – 19%) Breast cancer specific five-year survival rate was 79,93%. A better unadjusted survival was observed among women with disease diagnostic, immunohistochemical subtypes luminal A and B (p<0,0001), white skin color (p<0,0001), with tumor size ≤ 2.0cm (p<0,0001), without lymph node involvement (p<0,0001), in a less advanced disease stage (p<0,001), and of systemic treatment (p=0,01), and who used hormone therapy (p<0.0001). The main prognostic factors associated with poor survival were: subtypes triple negative (p<0.001), HER2 overexpression (p=0.01) and immunohistochemical profile unknown (p=0.01), no white race (p=0.02), advanced disease (stage III and IV – p<0.001), no realization of systemic treatment (p=0.009) and no use of first line chemotherapy (p=0.09). Conclusion: This research allowed identification of the profile and disease survival of breast cancer patients, according to imunohistochemical profile.
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Análise da expressão do receptor do fator de crescimento epitelial (EGFR) em pacientes portadores de adenocarcinoma pancreático submetidos a tratamento cirúrgico com intuito curativo / EGFR expression in pancreatic cancer patients submitted to surgical resection

Perini, Marcos Vinicius 07 January 2010 (has links)
INTRODUÇÃO: O câncer do pâncreas apresenta taxas anuais de mortalidade e incidência muito semelhantes, sendo uma das principais causas de morte por câncer no mundo. A agressividade do tumor e o retardo no seu diagnóstico são considerados responsáveis pela sua alta letalidade. O tratamento adjuvante convencional aumenta pouco a sobrevida a longo prazo e a terapia-alvo pode ser uma alternativa ao tratamento deste tipo de tumor. OBJETIVO: O objetivo do presente estudo é avaliar a expressão do receptor do fator de crescimento epitelial e seu eventual valor prognóstico em pacientes portadores de adenocarcinoma pancreático submetidos à ressecção cirúrgica. MÉTODO: Foram estudados retrospectivamente 88 pacientes portadores de adenocarcinoma pancreático operados no Serviço de Cirurgia de Vias Biliares e Pâncreas do HC-FMUSP e no Departamento de Cirurgia Abdominal Hospital A.C. Camargo no período de 1990 a 2006. RESULTADOS: Quarenta e sete (53,4%) pacientes do sexo feminino e 41 (46,6%) do masculino com idade mediana de 60 anos. As cirurgias realizadas foram duodenopancreatectomia com preservação do piloro (55,1%), gastroduodenopancreatectomia (34,8%), pancreatectomia corpo-caudal (6,8%) e gastroduodenopancreatectomia total (2,3%). A ressecção venosa portal foi realizada em 12 pacientes (13,5%). O tamanho tumoral médio foi de 3,75cm. Invasão vascular esteve presente em 31% dos casos e neural em 88,5%. A margem de ressecção estava comprometida em 33 pacientes (37,5%). Cinco (5,7%) pacientes eram do estádio IA, 15(17%) do IB, 19(21,6%) do IIA, 47(53,4) do IIB e dois (2,3%) do III.Observou-se diferença na expressão de EGFR na membrana celular entre o tecido tumoral e o tecido não tumoral (p=0,004); entre o tecido metastático linfonodal e o tecido não tumoral (p=0,02) mas não houve diferença quanto à sua expressão quando comparamos o tecido tumoral e o tecido metastático linfonodal (p=0,28). Dentre as variáveis clínicas e patológicas estudadas, observou-se diferença de expressão do EGFR entre os gêneros feminino e masculino (p=0,03), não havendo diferenças entre as outras variáveis. A sobrevida mediana global foi de 22,9 meses. A sobrevida cumulativa global em 1 ano, 3 anos e 5 anos foi de 48%, 20% e 18%, respectivamente. As sobrevidas cumulativas em 1 ano, 3 anos e 5 anos foram 77%, 30% e 8% no grupo sem expressão do EGFR na membrana tumoral versus 46%, 8% e 0% respectivamente no grupo com expressão do EGFR na membrana celular do tumor. Na análise univariada, as seguintes variáveis estiveram associadas a menor sobrevida: sexo masculino, ressecção venosa portal, invasão peri-neural, e vascular, invasão do tecido peri-pancreático, acometimento da margem de ressecção pancreática e expressão positiva de EGFR no tecido tumoral. Na análise multivariada, os fatores associados à sobrevida menor foram: gênero masculino, ressecção venosa portal, invasão vascular e invasão peri-neural. CONCLUSÃO: A expressão do EGFR na membrana celular é significativamente maior no tecido tumoral que no tecido pancreático não tumoral. A expressão do EGFR na membrana celular do tecido tumoral está associada a pior prognóstico (menor sobrevida). / INTRODUCTION: Pancreatic cancer is one of the main cancer related deaths in the world and its incidence is similar to its mortality. Biological aggressiveness and delayed diagnosis are a major concern. Adjuvant treatment has little impact on survival and the expression of potential target molecules has been undertaken in order to increase survival. OBJECTIVE: The aim of the present study is to study the expression of EGFR and its potential prognostic role in tumor, non-tumor and metastatic lymph node tissues of patient with pancreatic adenocarcinoma treated with surgical resection. MATHERIAL AND METHODS: Eighty eight patients with pancreatic adenocarcinoma operated at Serviço de Cirurgia de Vias Biliares e Pâncreas do HC-FMUSP and Departamento de Cirurgia Abdominal do Hospital A.C.Camargo were retrospectively studied between 1990 and 2003. RESULTS: Forty seven females (53,4%) and 41 males (46,6%) with median age of 60 years were studied. Pylorus preserving duodenopancreatectomy was performed in 55%, classical duodenopancreatectomy in 34,8%, distal pancreatectomy in 6,8% and total pancreatectomy in 2,3%. Portal vein resection was performed in 12 patients (13,5%). Mean tumor size was 3,75cm. Vascular and neural invasion were present in 31% and 88,5%, respectively. Positive surgical margin was present in 33 (37,5%) patients. Five (5,7%) patients were stage IA, 15(17%) stages IB, 19(21,6%) stages IIA, 47(53,4%) stages IIB and two (2,3%) stages III. There were difference in the membrane expression of EGFR between tumor and non tumor pancreatic tissue (p=0,004); between metastatic lymph node and non tumor pancreatic tissue (p=0,02); but there were no difference between tumor and metastatic lymph node tissue (p=0,28). Median survival time was 22,9 months. Cumulative one, three and five years survival were 48%, 20% and 18%. Cumulative survival at 1, 3 and 5 years were 77%, 30% and 8% in patients with negative expression of EGFR in tumor membrane and 46%, 8% and 0%, respectively in patients with positive EGFR expression in tumoral membrane. Univariate analysis showed that male gender, portal vein resection, neural, vascular and peri-pancreatic invasion invasion, positive surgical margin and positive membrane EGFR expression in tumoral tissue were correlated with poor survival. Multivariate analysis showed that male gender, portal vein resection, vascular invasion and peri-neural invasion are associated with lower survival after resection. CONCLUSION: EGFR membrane expression is different between tumor tissue and non tumor pancreatic tissue. EGFR membrane expression in tumoral tissue was associated with worst survival.

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