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.

Le cancer de la prostate est le cancer le plus fréquemment diagnostiqué et la troisième cause de mortalité liée au cancer chez les hommes au Canada. Un quart des patients diagnostiqués développeront une forme plus agressive de ce cancer. Bien que nous possédions plusieurs indices cliniques pronostiques dans les cancers localisés (score de Gleason, taux sérique d’antigène prostatique spécifique (APS), stade, etc.), ceux-ci sont insuffisants pour adéquatement distinguer les patients à faible risque de progression de ceux à haut risque. A ce jour, aucun biomarqueur pronostique n’est encore utilisé en clinique. Les cliniciens ont donc besoin de nouveaux outils plus efficaces pour stratifier ce cancer et pour s’assurer d’adapter au mieux le traitement à chaque patient. En nous basant sur la littérature et sur des études préliminaires (cohortes de moins de 65 patients), notre hypothèse est que les protéines PUMA-NOXA et les récepteurs membranaires de la famille ERBB seraient, lorsqu’utilisés en combinaison, des biomarqueurs prédictifs de la progression du cancer de la prostate. Les objectifs de cette thèse sont : 1) identifier et valider de bons anticorps pour chaque biomarqueur d’intérêt, 2) définir les niveaux d’expression de chaque biomarqueur sur une cohorte de 285 patients, et 3) établir les corrélations entre les niveaux d’expression et les données cliniques des patients. Dans l’optique d’une utilisation en clinique, des anticorps de type monoclonal ont été choisis pour identifier les biomarqueurs d’intérêts. Ces anticorps ont été testés et validés pour leur spécificité par immunobuvardage de type western blot et par immunofluorescence. La localisation de la protéine d’intérêt a été validée sur des échantillons de tissus de patients suivie de l’optimisation du multi-marquage sur les cellules épithéliales et basales. Après perfectionnement de l’analyse d’images, nous avons montré qu’une expression extrême (faible ou forte) de PUMA couplée à une forte expression de NOXA dans les glandes bénignes est associée à la rechute biochimique des patients. La présence de ces biomarqueurs dans les glandes bénignes permet d’envisager d’améliorer l’identification lors des premières biopsies des patients se qualifiant pour la surveillance active. Par ailleurs, le suivi de l’expression des récepteurs de la famille ERBB dans les glandes tumorales permet une stratification des patients atteints d’un cancer de la prostate en fonction des risques de rechute biochimique, de développement de métastases et de mort liée au cancer. Ainsi, les patients présentant la combinaison d’une forte expression de EGFR et d’une faible expression de ERBB3 sont les plus susceptibles de mourir spécifiquement de leur cancer de la prostate, en particulier si les cellules tumorales présentes en plus une faible expression de ERBB2 entrainant un fort risque de développer des métastases. Mon projet de doctorat aura donc permis d’identifier et de valider des biomarqueurs d’intérêt pour prédire l’évolution du cancer de la prostate et démontrer l’intérêt de suivre ces biomarqueurs en combinaison afin d’obtenir une meilleure stratification des patients. Ces résultats devront être validés sur une cohorte indépendante et multicentrique en vue de fournir aux cliniciens un plus grand nombre d’outils pour leur permettre de réaliser une stratification fine des patients atteints d’un cancer de la prostate, et ouvrirait la voie à de nouvelles stratégies thérapeutiques plus ciblées. / Prostate cancer is the most frequently diagnosed cancer and the third leading cause of cancer-related death in men in Canada. A quarter of patients will develop a more aggressive form of this cancer. While there are several clinical prognostic variables for localized prostate cancer (Gleason score, prostate specific antigen (PSA) levels, stage, etc.), these are insufficient to adequately distinguish between low and high-risk of progression cases. As a result, clinicians need new, more effective tools to stratify this cancer and to ensure that treatments are best tailored to each patient. To date, no prognostic biomarker has yet been used clinically. Based on the literature and preliminary studies of small cohorts (less than 65 patients), we hypothesize that the protein expression of PUMA-NOXA and ERBB family members could help with the prediction of prostate cancer progression. The objectives of this thesis are: 1) to identify and validate antibodies for each biomarker of interest, 2) to define the expression levels of each biomarker on a 285 patient cohort, 3) to evaluate the correlation between marker expression levels and patient clinical data. For clinical use, monoclonal-type antibodies were chosen to identify the biomarkers of interest. These antibodies were validated for specificity by western blot and immunofluorescence techniques. The localization of the protein of interest was further identified within samples of patient tissues and additional optimization involving combinatorial staining for epithelial and basal cells. After refining the imaging and statistical analysis of PUMA and NOXA in benign glands, we found that extreme (weak or strong) PUMA expression coupled with high NOXA expression was associated with biochemical relapse. In addition, these proteins have significant potential for predicting disease evolution based on the initial radical prostatectomy sample. The presence of these proteins in benign glands would allow the identification of patients less suitable for active surveillance. Additionally, statistical analysis of ERBB family receptors in tumor glands, when used alone, allow stratification of prostate cancer patients for the prediction of biochemical relapse, development of metastases and also specific death from prostate cancer. Moreover, patients expressing a combination of high EGFR expression and low ERBB3 expression are at high risk of biochemical relapse and are at higher risk of prostate cancer specific mortality. In addition, coupling this high EGFR – low ERBB3 combination to a low ERBB2 expression helps classify patients at high risk of developing metastases. My doctoral research project will have made it possible to identify and validate biomarkers of interest for predicting the progression of prostate cancer and demonstrating the interest of combining these biomarkers in order to achieve better stratification of patients with prostate cancer. In the context of clinical utility, these results need to be validated on an independent and multicenter cohort in order to confirm these findings. This would eventually provide clinicians with a greater number of tools at their disposal to correctly anticipate patient trajectories and possibly identify new therapeutic targets for the control of the disease.

<p> The ErbB2/Neu orphan receptor tyrosine kinase is amplified in 20-30% of breast and ovarian cancers and predicates poor patient prognosis. Five conserved tyrosine residues, autophosphorylated by Neu catalytic activity, "dock" adaptors and second messengers that activate discrete signalling pathways, most prominently the Ras/MAPK pathway, to regulate cell survival and proliferation. </p> <p> Genetic analysis using Drosophila provides an efficient means for identifying evolutionarily conserved signalling components. Neu and Drosophila EGFR overexpression directs Drosophila tissue development synonymously. Consistent with biochemical evidence, genetic analysis ofNeu signalling through individual pTyr revealed activating signals for 4(Yl144, YB; Y1201, YC; Y1226/7, YD; Y1253, YE) of the 5 sites. Strong Ras-dependent signalling was mediated through adaptors Grb-2 (YB) and SHC (YD). In contrast to biochemical evidence, a strong Ras component was not genetically detected for YC or YE. </p> <p> We have conducted two enhancer-suppressor screens to identify novel Ras and non-Ras requirements for YC signalling. For the first screen, a quantitative approach was designed to identify modification of an YC-specific wing notch phenotype. Thirty-two members of the Ras/MAPK signalling cassette were assessed. Sensitivity to Ras, Raf, MAPK and the Ras-related GTPase R-Ras was identified downstream ofYC. The second screen, a large-scale mutagenesis, took advantage of an YC-induced rough eye phenotype. From over 19 000 screened flies, 11 enhancers and 6 suppressors were isolated. One strong suppressor has been genetically mapped to the dual transcription factor and phosphatase eyes absent. Other promising Ras-dependent and Ras-independent modifiers await farther mapping. Results from both screens point to YC as a unique pTyr that uses both Ras-dependent and Ras-independent outputs. </p> / Thesis / Doctor of Philosophy (PhD)

No description available.

No description available.

ErbB2 gehört zu den Klasse I Rezeptor-Tyrosinkinasen und funktioniert als Ko-rezeptor bei der Vermittlung des Neuregulin-Signals. Während der Embryonal-entwicklung wird ErbB2 im Herzen, in den Neuralleistenzellen, im Muskel und in den Epithelien exprimiert (Kokai et al. 1987). Embryonen mit einer Null-Mutation im ErbB2 Gen sterben am Tag 10,5 der Embryonalentwicklung. Die Mutation bewirkt eine morphogenetische Fehlbildung des Herzens, die durch das Fehlen von ventrikulären Trabekeln gekennzeichnet ist (Lee et al. 1995). Weiterhin zeigen diese Embryonen Defekte in den Kranialganglien und in der primären sympathischen Ganglien-Kette, die von Neuralleistenzellen gebildet werden (Lee et al. 1995; Erickson et al. 1997; Britsch et al. 1998). Die herzspezifische Expression von ErbB2 cDNA ermöglicht ErbB2-/- Tieren, sich bis zur Geburt zu entwickeln. Dies erlaubte mir, spätere Funktionen des Rezeptors zu untersuchen. In den geretteten ErbB2-/- Embryonen erfolgte die Bildung der ventrikulären Trabekel, der fingerähnlichen Ausstülpungen des Myokards, zwischen dem 9. und 10. Tag in der Embryonalentwicklung. In den späteren Phasen der intrauterinen Entwicklung war das Herz der geretteten Tiere normal ausgebildet. In den ErbB2-/-R Embryonen fehlten Schwann'sche Zellen entlang der peripheren Nerven. Die Abwesenheit von Schwann'schen Zellen führte zum massiven Absterben von sensorischen und motorischen Neuronen des Rückenmarkes. Dabei zeigten sensorische Neuronen eine frühe Abhängigkeit von neurotrophen Faktoren, die von Schwann'schen Zellen produziert werden, während Motoneuronen diese Faktoren in einer späteren Phase benötigen. Zusätzlich ist bekannt, daß sensorische Neuronen und Motoneuronen neurotrophe Fakten benötigen, die von den Zielorganen, z.B. den Muskeln, produziert werden. Motoneuronen im thorakalen Rückenmark sind nur minimal betroffen, während die Degeneration von Moto-neuronen in den zervikalen und lumbalen Segmenten stark ausgeprägt ist. Verschiedene Motoneuron-Typen unterscheiden sich also in ihrer Abhängigkeit von neurotrophen Signalen. Weiterhin sind die peripheren Nerven der ErbB2-/-R Tiere defaszikuliert und ungeordnet. Der N. phrenicus, der das Diaphragma innerviert, retrahiert und ist am Tag 17 der Entwicklung vollständig degeneriert. Deshalb können die mutanten Tiere bei der Geburt nicht atmen und sterben infolgedessen. Überraschenderweise erfolgt in den geretteten ErbB2-/-R Embryonen die post-synaptische Expression und Aggregation der Acetylcholin-Rezeptoren. Die Phäno-typen der ErbB2-/-R und ErbB3-/- mutanten Tieren sind sehr ähnlich. Dies zeigt, daß ErbB2 eine essentielle Korezeptor-Funktion für ErbB3 in der Vermittlung der Neuregulin-Signale übernimmt. / ErbB2 belongs to class I of receptor tyrosine kinases and functions as a co-receptor by the transduction of the neuregulin signal. During embryonic development the ErbB2 gene is expressed in the heart, neural crest, in muscle and epithelial cells (Kokai et al. 1987). Embryos with null mutation of the ErbB2 gene die at midgestation. The mutation causes a morphogenetic defect that results in the absence of trabecules (Lee et al. 1995). In addition the mutant embryos show defects in cranial ganglia and in the primary sympathetic ganglia chain (Lee et al. 1995; Erickson et al. 1997; Britsch et al. 1998). The heart specific expression of ErbB2 cDNA allowed the mutant animals to survive till birth. This enabels me to study the late function of the receptor. In rescued ErbB2-/- embryos the ventricular trabecules, which are finger-like extensions of the myocardium, form properly between E9 and E10 of embryonic development. At late stages of intrauteral development the hearts of the rescued animals showed an overall normal growth. ErbB2-/- embryos lack Schwann cells along peripheral nerves. The absence of Schwann cells leads to enormous degeneration of sensory and motoneurons. Whereas sensory neurons show an early dependency on neurotrophic factors produced by Schwann cells, motoneurons revealed requirement of these factors during the late phase of their development. Moreover it is known that sensory and motoneurons require neurotrophic factors which are produced by their target tissues such as muscle. Motoneurons at the thoracic level of the spinal cord are minimaly affected, whereas the degeneration of motoneurons at cervical and lumbar segments of the spinal cord are pronounced. This indicates that different motoneuron types differ in their dependency on neurotrophic signals. Furthermore axons of peripheral nerves in ErbB2-/-R (rescued) animals show defasciculation and desorganization. Nervous phrenicus, that innervates the diaphragm muscle retracts and degenerates entirely at E17 of embryonic development. As a result newborn animals can not breath and die shortly after birth. Surprisingly, the expression and aggregation of AchRs (Acetylcholine Receptors) take place in rescued ErbB2-/-R embryos. The overall phenotype of ErbB2-/-R embryos is very similar to that of ErbB3-/- embryos. This substantiates the essential function of ErbB2 as the functional co-receptor for ErbB3 to transmit the neuregulin signal.

Magister Scientiae (Medical Bioscience) - MSc(MBS) / This study investigated the effects of TKIs on the growth and proliferation of MCF-7 breast carcinoma cells in culture. MCF-7 cells were exposed to different concentrations of TKIs alone and in combination with each other. Inhibition of cell growth by TKIs used individually occurred in a dose- and time-dependent manner. When EGFR Inhibitor I, EGFR Inhibitor II/BIBX1382 and the multi-specific EGFR/ErbB-2/ErB-4 Inhibitor were used in combination with each other at equimolar log dose concentrations, the combined effects on cell growth was significantly different to inhibitors used individually as reflected in a decreased EC50 (IC50) during combination treatments. Generally, for the combinations with DOX, CPL and the TKIs, synergistic as well as antagonistic effects were observed at isoeffective concentrations with resultant decreases in dose reduction indices (DRIs) implying greater efficacies with the respective combinations. In this study, conventional PCR was used to detect and illustrate the presence of the EGFR gene in the samples, while RT-qPCR was used to determine the mRNA expression levels of this gene in MCF-7 breast carcinoma cells