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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.
11

Die Bedeutung des Serumantigens des Onkoproteins HER-2/neu für die Diagnostik und Therapie des Mammakarzinoms

Lüftner, Diana 12 February 2004 (has links)
Diese Arbeit beschäftigt sich mit der prognostischen und prädiktiven Bedeutung der Serummessung des shed antigens des Onkoproteins HER-2/neu (s-HER-2/neu) für Mammakarzinompatientinnen in unterschiedlichen Erkrankungsstadien sowie unter verschiedenen Formen der Systemtherapie inklusive der Behandlung mit dem monoklonalen Antikörper Herceptin. Hierbei wurde der Stellenwert von s-HER-2/neu mit weiteren biochemischen Serummarkern (s-EGFR, s-uPA, CA 27.29) und etablierten Prognosefaktoren des Mammakarzinoms verglichen. Da HER-2/neu zu verschiedenen Zeitpunkten der Erkrankung mit verschiedenen Methoden an unterschiedlichen Materialien bestimmt werden kann, mußte schwerpunktmäßig auch die differentielle Wertigkeit von s-HER-2/neu im Vergleich zu Methoden der HER-2/neu-Bestimmung am Tumormaterial untersucht werden. Hierbei wurde insbesondere hinterfragt, ob die verschiedenen Methoden der HER-2/neu-Diagnostik stets zum gleichen Ergebnis führen, welche biologischen und technischen Ursachen möglichen Diskordanzen zugrunde liegen, und welche Konsequenzen diese Diskordanzen für die Therapiewahl (vor allem mit Herceptin beim metastasierten Mammakarzinom) mit sich bringen. Es wurden folgende Ergebnisse erzielt: - Grenzwerte: s-HER-2/neu: 50 ng/ml mit großer Wahrscheinlichkeit auch eine HER-2/neu-Überexpression am Tumorgewebe aufweisen. - Insgesamt 70% der Patientinnen mit HER-2/neu-negativen Tumoren hatten bei der späteren Fernmetastasierung einen erhöhten s-HER-2/neu-Spiegel. Diese Zunahme des Nachweises der HER-2/neu-Positivität zwischen Gewebenachweis am Primärtumor und dem Serumnachweis im Stadium IV ist nicht zufällig (p=0,001) und allenfalls teilweise durch den Einfluß der Tumormasse erklärbar. Klonale Veränderungen müssen in Erwägung gezogen werden. / This work focuses on the prognostic and predictive impact of the determination of the shed antigen of the oncoprotein HER-2/neu in serum (s-HER-2/neu) for breast cancer patients in different stages of the disease as well as under different forms of systemic therapy including treatment with the monocloncal antibody Herceptin. The biological meaning of s-HER-2/neu was compared to other serum markers (s-EGFR, s-uPA, CA 27.29) and established prognostic markers in breast cancer. As HER-2/neu can be measured at different times during the course of the disease using different methods and material, the differential meaning of s-HER-2/neu had to be investigated in relation to methods of HER-2/neu determination in tissue. Key questions were whether different methods of HER-2/neu testing lead to the same result, what biological and/or technical reason may lead to discordances, and if so, which are the consequences of these discordances for therapeutic decision making (before all Herceptin therapy in metastatic breast cancer). The results of the investigations are as follows: - Cut-offs of normal: s-HER-2/neu: 50 ng/ml are most probably HER-2/neu-positive in tissue. - Altogether, 70% of the patients with HER-2/neu negative tumors showed elevated s-HER-2/neu concentrations at later metastatic spread. This increase of the number of HER-2/neu positivity between tissue determination at the primary tumor and the serum results at stage IV disease cannot be explained by pure coincidence (p=0.001) and can only in part be explained by the influence of tumor burden . Clonal changes during the course of the disease must be considered.
12

A expressão imuno-histoquímica do marcador molecular Citoqueratina 19 e da proteína Her-2/neu (C-erbB2) em bócios operados na Fundação Hospital Adriano Jorge, em Manaus

Cattebeke, Lesemky Carlile Herculano 12 December 2012 (has links)
Made available in DSpace on 2015-04-20T12:31:16Z (GMT). No. of bitstreams: 1 lesemky.pdf: 1202883 bytes, checksum: f8220049d5a1bd344120a49c3ed2500a (MD5) Previous issue date: 2012-12-12 / Cytokeratin 19 (CK 19) is a molecular marker that express cell replication and differentiation, and HER-2 oncogene (Human Epidermal Growth factor receptor-Type 2) is the second member of the human epidermal growth factor receptor (EGFR) family. Its overexpression can mean aggressiveness and poor prognostic in various kinds of tumors, as breast, lung and prostate. In last few decades the diagnostic of morphological changes of the thyroid gland was increased. When being diagnosed with ultrasound, the thyroid nodule prevalence reaches 20% to 30% in the general population. The aim of this prospective study is verify the presence of these markers in thyroid glands in operated non-coastal Amazon inhabitants, and its relationship with pathologic findings. We selected 34 samples of formalin-fixed, paraffin-embedded thyroid tumor tissues, from patients treated at Hospital Adriano Jorge, Manaus, Amazonas. The patients consisted of six men and 28 women, aged between 25 and 76 years, average 47 years. The tissues corresponded to nine multinodular goiter (MNG), seven colloid goiters (CG), five nodular hyperplasia (NH) four adenomatous goiters (AG), three papillary thyroid microcarcinoma (PTMC) and five papillary thyroid carcinomas (PTC). Immunohistochemistry (IHC) staining with CK 19 and HER-2 were performed using the labeled streptavidin biotin peroxidase complex system (LSAB2, DAKO, USA) on all tissues using monoclonal antibodies BA17 mab mouse (Dako M0772, USA) and SP3 rabbit mab (Spring M3034, USA) and inferential statistical analysis applying (Fisher exact test with 5% significance level). HER-2 IHC was not found in all samples. We found a strong positive reactivity for IHC CK19 in all 3 patients with PTMC, in four with PTC, one with MNG, and one with CG. We found focal positivity for CK 19 in one PTC, two MNG, 4 CG and one AG. Statistical significance was found only between CK 19 and histopathology. The results suggest thats HER-2 oncogene has no predictive or prognostic value in thyroid tissues and CK 19 marker showed affinity for PTC, although it is also found in benign tissues with less intensity. / A citoqueratina 19 (CK 19) é um marcador molecular que expressa diferenciação e replicação celular e o oncogene HER-2 (Human Epidermal Growth factor receptor-Type 2), membro da família Fator de Crescimento Epidérmico Humano (EGFR), uma proteína que quando sobre-expressa pode significar maior ploriferação celular e agressividade em vários tipos de tumores, dentre eles mama, pulmão e próstata. Nas últimas décadas vêm aumentando o diagnóstico de alterações morfológicas da glândula tireoide, sendo que quando diagnosticado à ultrassonografia a prevalência do nódulo tireoideano chega a 20% a 30% na população geral. Objetivamos neste estudo prospectivo verificar a presença destes marcadores em glândulas tireoideas operadas em pacientes habitantes em região amazônica não litorânea, e sua relação com as alterações morfológicas encontradas. Foram selecionadas 34 amostras de tecido tireoidiano preservados em formol e armazenados em parafina, de pacientes operados na Fundação Hospital Adriano Jorge, de Manaus, Amazonas. Os pacientes corresponderam a seis homens e 28 mulheres, com idade entre 25 e 76 anos e média de 47 anos. Os tecidos corresponderam a nove bócios multinodulares (BMN), sete bócios coloides (BC), cinco hiperplasias nodulares (HN) quatro bócios adenomatosos (BA), três microcarcinomas papilíferos (MCP) e cinco carcinomas papilíferos da tireóide (CPT). Exames de imuno-histoquímica em busca dos marcadores CK19 e HER-2 foram realizados em todos os tecidos usando anticorpos monoclonais BA17 (mab rato, Dako M0772, EUA) e SP3 (policlonal em coelho, Spring M3034, EUA) e o método esteptavidina-biotina-peroxidade (Kit LSAB, Dako, EUA) e análise estatística inferencial aplicando o teste Exato de Fisher com nível de significância de 5%. Não foi encontrada positividade para o marcador HER-2 em tecidos tireoidianos malignos ou benignos. Foram encontrados positividade média a forte intensidade para CK19 em todos os três pacientes com MCP, quatro CPT, um BMN e um BC. Foram encontrados positividade focal em um CPT, dois BMN, quatro BC e um BA. A análise estatística demonstrou significância estatística somente entre as variáveis CK 19 e tipo histopatológico. Os resultados da amostra analisada demonstraram que a pesquisa no oncogene HER-2 não apresentou presença deste marcador em nenhum dos tecidos tireoidianos, e o marcador CK 19 foi presente em maior intensidade nos casos de Carcinoma que nos tecidos benignos onde foi encontrado.
13

An Evaluation of the Effects of a Novel Estrogen, Progesterone, and Melatonin Hormone Therapy on Mammary Cancer Development, Progression and Uterine Protection in the MMTV-Neu Mouse Model

Dodda, Balasunder 15 June 2015 (has links)
Estrogen therapy (ET) is most effective to reduce menopausal symptoms and prevent other disorders associated with estrogen deficiency. However, Women's Health Initiative studies found that hormone therapy (HT) containing estrogen plus progestogen, but not estrogen-alone increases breast cancer (BC) risk. To prevent the increase in BC risk and yet relieve menopausal symptoms, a novel HT with 17β-estradiol (E2) for symptom relief, progesterone (P4) for uterine protection and melatonin (Mel) for both BC and uterine protection was designed. Inclusion of Mel was postulated to offer uterine protection with lower P4 dose and protect against BC. The goal of this study was to assess the efficacy of E2, P4 and Mel Therapy (EPMT) on mammary cancer (MC) and uterine protection in MMTV-Neu mouse model that mimics HER2 BC. Starting at 2 months age, female mice received Mel in drinking water at night to supplement endogenous Mel surge; while E2 and P4 Therapy (EPT) was provided continuously in diet until 14 months with weekly MC onset and growth monitoring. Normal mammary, uterus and mammary tumors harvested by month 14 were analyzed for potential mechanisms. The results from this study revealed that EPMT delayed tumor onset leading to a decrease in MC incidence. In addition, mice in the EPMT group had no increase in relative uterine weight as opposite to an increase of this parameter in EPT group versus control. The percent tumor-bearing mice with gross metastatic lung lesions were reduced in Mel, EPT and EPMT groups. Mel receptor, estrogen receptor (ER) and progesterone receptor (PR) expression revealed that all tissues examined have Mel receptors. However, ER and PR expression varied. In normal mammary tissue, both ERα and PR were detected by immunohistochemistry. However, no ERα and PR were detected in mammary tumors of same mice. In uterus, mice given Mel or EPMT had significant decreases in PR expression but no change in ERα expression compared to control suggesting that Mel-mediated inhibition of ER binding to estrogen response elements may be involved in the down regulation of uterine PRs. Overall, this study reveal that EPMT prevents mammary cancer and may protect against uterotrophy. / Mylan School of Pharmacy and the Graduate School of Pharmaceutical Sciences; / Pharmacology / PhD; / Dissertation;
14

In Vitro and In Vivo Effects of Conjugated Linoleic Acid on Mammary Tumorigenesis

Flowers, Margaret January 2008 (has links)
Conjugated linoleic acid (CLA) exhibits multiple biological and molecular activities that have made it the subject of considerable nutrition-related research. Numerous studies support broad acting anti-tumor effects including anti-inflammatory, anti-proliferation, and pro-apoptosis in a variety of model systems. CLA’s ability to influence multiple tumor promoting pathways, without toxicity, may prove valuable in the chemoprevention of breast cancer. The overall objective of this dissertation research was to investigate the potential of CLA in the chemoprevention of breast cancer in a subgroup of women at risk of developing estrogen receptor (ER) negative disease. Overexpression of either the ERBB2 oncogene or the epidermal growth factor receptor (EGFR) is a common event in ER negative breast cancer. To respond to this association, the stated research objective was pursued in relevant model systems. The primary hypothesis was that CLA would downregulate the ERBB2 receptor in vitro and inhibit mammary tumorigenesis in vivo. The t10c12 CLA isomer significantly reduced ERBB2 protein expression in the ERBB2 overexpressing cell line SKBr3. This was accompanied by a decrease in NFκB nuclear localization, cyclooxygenase-2 (COX2)-derived prostaglandin (PG) E2 production, increased apoptosis, and inhibition of proliferation. In contrast to the in vitro data, however 1% dietary CLA had pro-tumor effects in the PyV-mT transgenic mouse model, Mammary gland whole mounts indicated a significant loss of adipose in the CLA-treated group compared to controls that was confirmed by the downregulation of adipocyte-specific genes including PPARγ and adiponectin. CLA’s effect on the adipose was supported by decreases in fatty acid synthase at the protein and mRNA level. cDNA microarray revealed significant downregulation of cytoskeletal and adhesion-related genes in the CLA-treated group. These data suggest CLA’s combined effect on the adipose and epithelial architecture may have promoted tumor growth in this model While the large body of evidence supporting an anti-tumor effect of CLA can not be discounted, the studies herein demonstrate the complexity of its action that may not be captured in simple model systems. Reports of adverse effects of mixed isomers or the t10c12 purified isomer lend caution to supplementation that is supported by our in vivo data.
15

The Role of Myeloid-Derived Suppressor Cells in the Immunotherapy of Breast Carcinomas

Morales, Johanna 10 April 2009 (has links)
Myeloid-derived suppressor cells (MDSC) are a heterogeneous population of immature cells at various stages of differentiation. These cells are broadly characterized by the simultaneous expression of the surface markers CD11b and Gr1 and have been found to accumulate in large numbers in response to many different tumors in both mice and humans, including HER2/neu+ breast cancers. The adoptive immunotherapy of cancers has been a promising field, yet the clinical efficacy of adoptive immunotherapies targeted against human breast cancers and many other cancers has been extremely limited. Given the influx of MDSC in tumor-bearing individuals, we hypothesized that these cells were the reason for the failure of adoptively transferred T cells to effectively reject primary tumors. Using either monoclonal antibodies or the chemotherapeutic drug, gemcitabine, we aimed to eliminate MDSC cells in vivo to determine if adoptively transferred T cells would be more effective in the absence of these cells. We further aimed to characterize the mechanism of T cell suppression by MDSC and the tumor-derived soluble factor(s) responsible for their accumulation. We have found that the elimination of MDSC in vivo does result in significant tumor inhibition when adoptively transferred T cells are administered. Furthermore, the use of gemcitabine in conjunction with adoptively transferred T cells resulted in complete tumor rejection in 100% of mice and was accompanied by large antibody titers against HER2/neu as well as strong recall responses characterized by IFN-g release and subsequent rejection of further tumor challenges. We report herein that suppression by MDSC is contact dependent and affects the proliferation of both CD4+ and CD8+ T cells. The accumulation of MDSC in tumor-bearing mice can be entirely attributed to tumor-derived soluble factors, with GM-CSF specifically causing the generation and maintenance of these cells. Our findings suggest that the adoptive immunotherapy of breast carcinomas in a clinical setting should be combined with the use of gemcitabine, and that the use of GM-CSF as an adjuvant in cancer vaccines should be carefully re-evaluated as this cytokine may result in increased MDSC accumulation in vivo.
16

Identification d'un nouveau gène suppresseur de tumeurs candidat (EphA10) dans les tumeurs mammaires des souris transgéniques MMTV/neu

Depault, François January 2005 (has links)
Thèse numérisée par la Direction des bibliothèques de l'Université de Montréal.
17

ETUDE DU DOMAINE TRANSMEMBRANAIRE DE RECEPTEUR TYROSINE KINASE DANS UN ENVIRONNEMENT MEMBRANAIRE. ASPECTS STRUCTURAUX ET MECANISTIQUES EXPLORES PAR DYNAMIQUE MOLECULAIRE

ALLER, Pierre 06 December 2004 (has links) (PDF)
La dimérisation induite par la fixation de ligand est nécessaire à l'activation des récepteurs tyrosine kinase. Le domaine transmembranaire unique de ces protéines joue un rôle crucial dans ces mécanismes. Le récepteur Neu chez le rat et son homologue ErbB2 chez l'humain sont à l'origine de nombreux cancers provoqués par la mutation ponctuelle Val/Glu dans le segment transmembranaire ou la surexpression du récepteur. La structure du domaine transmembranaire dans le récepteur dimère semble déterminante dans les processus d'activation. Les simulations de dynamique moléculaire montrent que, dans une membrane modèle constituée de DMPC ou de POPC hydratés, les hélices transmembranaires de Neu sauvage et oncogénique s'associent préférentiellement en enroulement gauche formant une interface symétrique. Dans le cas de Neu oncogénique le résidu polaire Glu, enfoui dans la membrane, stabilise les interactions entre hélices en formant de fortes liaisons hydrogène
18

An Evaluation of the Effects of a Novel Estrogen, Progesterone, and Melatonin Hormone Therapy on Mammary Cancer Development, Progression and Uterine Protection in the MMTV-Neu Mouse Model

Dodda, Balasunder 16 April 2015 (has links)
Estrogen therapy (ET) is most effective to reduce menopausal symptoms and prevent other disorders associated with estrogen deficiency. However, Women's Health Initiative studies found that hormone therapy (HT) containing estrogen plus progestogen, but not estrogen-alone increases breast cancer (BC) risk. To prevent the increase in BC risk and yet relieve menopausal symptoms, a novel HT with 17β-estradiol (E2) for symptom relief, progesterone (P4) for uterine protection and melatonin (Mel) for both BC and uterine protection was designed. Inclusion of Mel was postulated to offer uterine protection with lower P4 dose and protect against BC. The goal of this study was to assess the efficacy of E2, P4 and Mel Therapy (EPMT) on mammary cancer (MC) and uterine protection in MMTV-Neu mouse model that mimics HER2 BC. Starting at 2 months age, female mice received Mel in drinking water at night to supplement endogenous Mel surge; while E2 and P4 Therapy (EPT) was provided continuously in diet until 14 months with weekly MC onset and growth monitoring. Normal mammary, uterus and mammary tumors harvested by month 14 were analyzed for potential mechanisms. The results from this study revealed that EPMT delayed tumor onset leading to a decrease in MC incidence. In addition, mice in the EPMT group had no increase in relative uterine weight as opposite to an increase of this parameter in EPT group versus control. The percent tumor-bearing mice with gross metastatic lung lesions were reduced in Mel, EPT and EPMT groups. Mel receptor, estrogen receptor (ER) and progesterone receptor (PR) expression revealed that all tissues examined have Mel receptors. However, ER and PR expression varied. In normal mammary tissue, both ERα and PR were detected by immunohistochemistry. However, no ERα and PR were detected in mammary tumors of same mice. In uterus, mice given Mel or EPMT had significant decreases in PR expression but no change in ERα expression compared to control suggesting that Mel-mediated inhibition of ER binding to estrogen response elements may be involved in the down regulation of uterine PRs. Overall, this study reveal that EPMT prevents mammary cancer and may protect against uterotrophy. / Mylan School of Pharmacy and the Graduate School of Pharmaceutical Sciences; / Pharmacology / PhD; / Dissertation;
19

HER-2/neu-targeted immunoprevention of breast cancer

Sas, Sheena Emm 27 March 2007
Improvements in the use of traditional breast cancer therapies have improved the overall survival of women with early stage disease. Remarkable advances in research have created a unique opportunity for developing active vaccination strategies that engage the bodys own immune system in the fight against breast cancer. Human Epidermal Growth Factor Receptor 2 (HER-2/neu) is a breast tumor antigen (Ag) commonly overexpressed in 30% of breast cancer cases. HER-2/neu-targeted DNA-based and fiber-modified dendritic cell (DC)-based vaccines are both analyzed as potent elements in eliciting HER-2/neu specific antitumor immune responses. A HER-2/neu-expressing DNA plasmid (pcDNA/neu) coadministered with the appropriate adjuvant vector was the first study looking at improving vaccine efficacy and enhancing immune responses. Various protection and prevention studies, using FVB/N (wild-type) and FVB/neuN [transgenic (Tg)] mice and Tg1-1 tumor cells, derived from a spontaneous tumor from Tg mice, are used to help narrow down the large panel of adjuvant vectors. Results showed the adjuvant vector pcDNA/TNF-α, when coadministered with pcDNA/neu, induced more efficient protective tumor-specific immunity and significantly delayed breast cancer development in Tg mice.<p>Another study utilized an<i>in vivo</i> murine tumor model expressing the rat neu Ag to compare the immunization efficacy between DC transduced with replication-deficient fiber-modified adenovirus (AdV) containing neu (AdV(RGD)neu), to form DC(RGD)neu, and non-modified DCneu. DC(RGD)neu displayed an upregulation of immunologically important molecules and inflammatory cytokine expression through FACS Analysis, and more importantly increased expression of neu, when compared to DCneu. DC(RGD)neu stimulated a higher percentage of HER-2/neu-specific CD8+ T cells, a stronger neu-specific CTL response, and induced a much stronger Th1- and Th2-type immune response than DCneu. Furthermore, vaccination with DC(RGD)neu induced enhanced protective tumor-specific immunity compared to DCneu in wild-type and Tg mice.<p>Overall the construction of recombinant vectors containing two transgenes (HER-2/neu and TNF-α), can not overcome the induction of HER-2/neu-directed immune tolerance. The fiber-modified (RGD) DCneu vaccine induced enhanced anti-HER-2/neu immunity compared to non-modified DCneu in the prevention of breast cancers.
20

HER-2/neu-targeted immunoprevention of breast cancer

Sas, Sheena Emm 27 March 2007 (has links)
Improvements in the use of traditional breast cancer therapies have improved the overall survival of women with early stage disease. Remarkable advances in research have created a unique opportunity for developing active vaccination strategies that engage the bodys own immune system in the fight against breast cancer. Human Epidermal Growth Factor Receptor 2 (HER-2/neu) is a breast tumor antigen (Ag) commonly overexpressed in 30% of breast cancer cases. HER-2/neu-targeted DNA-based and fiber-modified dendritic cell (DC)-based vaccines are both analyzed as potent elements in eliciting HER-2/neu specific antitumor immune responses. A HER-2/neu-expressing DNA plasmid (pcDNA/neu) coadministered with the appropriate adjuvant vector was the first study looking at improving vaccine efficacy and enhancing immune responses. Various protection and prevention studies, using FVB/N (wild-type) and FVB/neuN [transgenic (Tg)] mice and Tg1-1 tumor cells, derived from a spontaneous tumor from Tg mice, are used to help narrow down the large panel of adjuvant vectors. Results showed the adjuvant vector pcDNA/TNF-α, when coadministered with pcDNA/neu, induced more efficient protective tumor-specific immunity and significantly delayed breast cancer development in Tg mice.<p>Another study utilized an<i>in vivo</i> murine tumor model expressing the rat neu Ag to compare the immunization efficacy between DC transduced with replication-deficient fiber-modified adenovirus (AdV) containing neu (AdV(RGD)neu), to form DC(RGD)neu, and non-modified DCneu. DC(RGD)neu displayed an upregulation of immunologically important molecules and inflammatory cytokine expression through FACS Analysis, and more importantly increased expression of neu, when compared to DCneu. DC(RGD)neu stimulated a higher percentage of HER-2/neu-specific CD8+ T cells, a stronger neu-specific CTL response, and induced a much stronger Th1- and Th2-type immune response than DCneu. Furthermore, vaccination with DC(RGD)neu induced enhanced protective tumor-specific immunity compared to DCneu in wild-type and Tg mice.<p>Overall the construction of recombinant vectors containing two transgenes (HER-2/neu and TNF-α), can not overcome the induction of HER-2/neu-directed immune tolerance. The fiber-modified (RGD) DCneu vaccine induced enhanced anti-HER-2/neu immunity compared to non-modified DCneu in the prevention of breast cancers.

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