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The Global ETD Search service is a free service for researchers
to find electronic theses and dissertations. This service is
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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.
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Showing 1 to 7 of 7 (0.054 seconds)| 1 |
Overcoming the Challenges of Primary Tumor Management in Patients with Metastatic Colorectal Cancer Unresectable for Cure and an Asymptomatic Primary Tumor / 無症状かつ切除不能転移性大腸癌症例における原発巣マネージメントMatsumoto, Takuya 24 March 2014 (has links)
京都大学 / 0048 / 新制・課程博士 / 博士(医学) / 甲第18175号 / 医博第3895号 / 新制||医||1003(附属図書館) / 31033 / 京都大学大学院医学研究科医学専攻 / (主査)教授 上本 伸二, 教授 武藤 学, 教授 森田 智視 / 学位規則第4条第1項該当 / Doctor of Medical Science / Kyoto University / DGAM
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Translational assessment of primary tumor-derived cellsWu, Eric Longhua 22 January 2016 (has links)
Only a few individual cells within less than 5% of all primary tumors form the cell lines commonly used in cancer research. These growth bottlenecks result in cell lines that are often poor models of primary tumors. Co-culture of primary tumor-derived cells with an irradiated mouse fibroblast feeder layer and ROCK inhibitor, known as the Georgetown Method, offers a way to culture over 80% of tumor-derived cells in vitro to create more representative tumor cell models. In our studies, we optimized the Georgetown Method to culture head and neck cancer cells, including oropharyngeal squamous cell carcinoma, and investigated its mechanism of conditionally immortalizing cells in culture. Differential trypsinization and regular feeder layer replacement were found to significantly improve the efficacy of immortalizing co-cultured cells at both atmospheric and physiological oxygen levels. Medium conditioned by irradiated fibroblasts can also substitute for direct co-culture with a feeder layer. The Georgetown Method was found to maintain low levels of p16 in co-cultured cells, suggesting a potential mechanism by which the Georgetown Method prevents differentiation and senescence. Our ability to culture over 80% of primary tumor-derived cells allows us to test the translational value of tumor-derived cell cultures and xenografts using BH3 profiling. Conditioned medium simplifies maintenance of cell cultures and will also allow us to perform high-throughput screens without the need to separate tumor-derived cells from the fibroblast feeder layer. The Georgetown Method provides opportunities to expand small tissue specimens for future diagnostics, therapeutics, and biobanking.
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Rôles des EMT "master-gènes" pendant la progression carcinomateuse mammaire / Roles of EMT transcription factors in controlling cell clonal dynamics and invasiveness during emergence of tumor resistance in breast cancer subtypesLakis, Emile 30 November 2017 (has links)
Ce projet explore les mécanismes de la morphogenèse des glandes mammaires, comme modèle de progression du carcinome du sein. La morphogenèse de la glande mammaire résulte de la coordination de réponses cellulaires distinctes (prolifération, différenciation, motilité, invasivité, apoptose) régulées par de nombreuses voies, y compris Wnt, EGF, FGF, Notch, SHH, Myc et l'activation hormonale. Nous estimons qu'il est essentiel d'analyser individuellement l'impact de ces voies dans la modulation de la prolifération, de la différenciation, de la motilité, de l'invasivité, de l'apoptose, de la cohésion intercellulaire et de la polarité dans les cellules impliquées dans une migration morphogénétique cohérente.Nous avons développé des modèles en 3D améliorés pour analyser l'impact d'EMT-TF dans un environnement 3D. Notre système permet de surveiller simultanément les voies mentionnées au niveau cellulaire pendant trois semaines, une période ajustée pour tester les médicaments de chimiothérapie. Notre premier modèle décrit l'émergence primaire des cellules envahissantes de carcinome mammaire de l'épithélium mammaire. Les cellules sont traitées avec des médicaments définis ou seront transfectées avec diverses constructions (en cours de validation) améliorant ou réprimant des voies spécifiques telles que Slug, en plus des constructions permettant de suivre l'évolution des structures cellulaires par marquage GFP en vidéomicroscopie. / This project explores the mechanisms of mammary gland morphogenesis, as a model for breast carcinoma progression. Mammary gland morphogenesis results from the coordination of distinct cell responses (proliferation, differentiation, motility, invasiveness, apoptosis) integrated by numerous pathways, including Wnt, EGF, FGF, Notch, SHH, Myc and hormonal activation. For the purpose of this study, we feel it is critical to analyze individually the impact of theses pathways in modulating proliferation, differentiation, motility, invasiveness, apoptosis, intercellular cohesion, and polarity in cells involved in a coherent morphogenetic migration.We have designed improved 3D models to analyze the impact of EMT-TF in a 3D environment. Our system allows monitoring simultaneously the mentioned pathways at a cellular level for three weeks, a period adjusted to test chemotherapy drugs.Our first model describes the primary emergence of invading breast carcinoma cells from mammary epithelium. Cells are treated with defined drugs or will be transfected with various constructs (under validation) enhancing or repressing specific pathways such as Slug, in addition to constructs allowing the monitoring of cell structures by GFP labeling for video microscopy..
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The Lymphatic System in Breast Cancer MetastasisOdalys Torres Luquis (11200086) 29 July 2021 (has links)
The leading cause of breast cancer-associated death is metastasis. During metastasis, tumor cells metastasize from primary tumors to distant organs via the circulatory and lymphatic systems. However, in 80% of solid tumors, metastasis via the lymphatic system precedes metastasis via the vascular system. There is a lot of information about metastasis through the circulatory system. However, not much information is available about the tumor cell dissemination through the lymphatic system or the lymphatic microenvironment that aids in this process in breast cancer metastasis. In addition, the molecular properties of tumor cells as they exit the primary tumor into the afferent lymphatics en route to the sentinel lymph nodes (SLNs) are not yet known.<br><div><br></div><div>This project aims to determine why and how tumor cells metastasize to the lymphatic system. The proposal is based on the hypothesis that active migration is needed for tumor cells to spread via the lymphatic vessels. Thus, finding and understanding the molecules that contribute to this can be a breakthrough for breast cancer metastasis therapy.<br></div><div><br></div><div>The goals of this thesis are to 1) Examine the molecular, genetic, and proteomic characteristics of circulatory tumor cells and compare these to the primary tumor and lung metastasis, 2) Examine the role of Toll-like receptors in tumor cell migration to the lymph node, and 3) Identify the difference in protein expression among two different types of breast cancer (Triple-Negative and Luminal A) and understand their aggressive biology.<br></div>
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Resection of the Primary Osteosarcoma Terminates Self-seeding and Facilitates MetastasisLe Pommellet, Helene Marie 15 August 2017 (has links)
No description available.
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Metastases and Rare Primary Neoplasms of Salivary GlandsAl-Abbadi, Mousa A. 09 March 2011 (has links)
No description available.
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Cell type-dependent differential activation of ERK by oncogenic KRAS or BRAF in the mouse intestinal epitheliumBrandt, Raphael 10 March 2023 (has links)
Kolorektale Karzinome (CRC) zeigen eine heterogene Ätiologie. Die Progression prämaligner Vorläufer zu CRC unterscheidet (U) sich in Morphologie, molekularen Veränderungen und Interaktion mit der Tumorumgebung. CRC weisen oft onkogene Mutationen in KRAS und BRAF auf. Diese steigern die MAPK Signalwegaktivität (Mpa). Obwohl sie im selben Signalweg wirken, sind KRAS und BRAF auf die CRC-Entitäten U verteilt. Dabei ist KRAS häufiger im sogenannten konventionellen und BRAF im serratierten Weg zu CRC mutiert. In dieser Studie nutzte ich murine intestinale Organoide (iO), die induzierbare (Ind) KRAS oder BRAF Onkogene exprimieren. Große U zwischen KRAS und BRAF zeigten sich sowohl in Signaltransduktion (ST) als auch im Phänotyp. Phosphoprotein-, ERK-Reporter-, scRNA-Seq und EM-Analysen ergaben eine starke Mpa durch BRAF, die zu hoher Expression von MAPK-Zielgenen und Verlust der epithelialen Integrität führte. iO nach KRAS-Ind blieben intakt, korrelierend mit moderater, zelltypspezifischer (ZS) Mpa in sekretorischen und undifferenzierten Zellen. Die meisten Enterozyten waren Mpa-negativ. ERK-Reporter zeigten: Das ZS Muster der Mpa ist nicht nur gegenüber KRAS, sondern auch dem Entzug von Wachstumsfaktoren stabil. Dies spricht für eine intrinsische, robuste Regulierung der Mpa. BRAF-Ind Mpa setzte die ZS Regulierung der MAPK außer Kraft und schädigte das Gewebe, im Einklang mit einer oberen Grenze tolerabler Mpa. Die ZS Mpa wurde in CRC-Zelllinien bestätigt, deren Mpa durch KRAS aber nicht BRAF U ausfiel. Ferner, nutzte ich iO mit bCatenin+KRAS-Ind, um den konventionellen Weg zu CRC zu modellieren. Die Kombination führte zu synergistischen Effekten, die sich in EGFR-unabhängigem Wachstum und der
Aufhebung der ZS Mpa-Blockade äußerten, die durch eine Verschiebung der Differenzierung zu mehr Progenitorzellen bewirkt wurde. Zusammenfassend konnte ich U in der Mpa durch KRAS oder BRAF im Darmepithel feststellen, was dazu beiträgt, deren Rollen in der CRC-Genese zu bestimmen. / Colorectal cancer (CRC) is a disease with heterogeneous etiology. Premalignant lesions
follow distinct routes of progression to carcinoma reflected by differences in morphology,
molecular alterations and the tumor environment. Mutant KRAS and BRAF are frequent,
leading to MAPK pathway activation (Mpa), which is relevant for CRC therapy. Despite
acting in the same pathway, mutant KRAS and BRAF segregate to different entities, as KRAS
is more frequent in the conventional- and BRAF being specific for the serrated route to
CRC. I used murine intestinal organoids (iO) expressing inducible oncogenic KRAS or BRAF
to study the impact of oncogenes in primary cells. I found marked differences in signal
transduction and phenotype. Phospho-protein, ERK-reporter, scRNA-seq and EM data showed
strong Mpa upon BRAF induction followed by ERK-target gene expression leading to tissue
disruption. In contrast, KRAS left the tissue intact resulting in less and cell
type-dependent Mpa limited to secretory cells, a subset of late-stage enterocytes and
undifferentiated crypt cells. Most enterocytes were irresponsive to KRAS. The pattern of
Mpa was robust towards KRAS or growth factor depletion arguing in favor of intrinsic,
resilient MAPK regulation. In iO, BRAF-induced Mpa could break this cell type-specific
regulation, indicating an upper limit of tolerable Mpa. I validated these findings in CRC
cell lines that differed in Mpa in response to oncogenic KRAS but not BRAF. Finally, I
used iO expressing an inducible form of stabilized bCatenin in combination with KRAS to
mimic events frequently found in the conventional pathway to CRC. Expression of KRAS and
bCatenin synergized in driving EGFR independent growth and breaking the villus-specific
block of Mpa by altering differentiation towards progenitor cell types. In summary, this
study emphasizes differences between Mpa induced by oncogenic KRAS or BRAF which helps
clarifying their nature in different etiological routes to CRC genesis.
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