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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.
61

The effect of laser induced thermal ablation on liver tumours

Nikfarjam, Mehrdad Unknown Date (has links) (PDF)
Laser thermal ablation (LTA) is an in situ ablative technique that induces heat destruction of liver tumours. Despite increasing clinical use of LTA, reports of long-term outcomes and limitation of treatment in specific cohorts of patients with liver tumours are lacking. In addition, the mechanisms of action of therapy have not been fully elucidated. This study highlights the long-term clinical results and limitations of LTA in the treatment of a cohort of patients with unresectable colorectal liver metastases and examines the mechanisms of action of thermal ablative injury in a murine model.
62

Gallium, un candidat prometteur pour le traitement des pathologies osseuses / Gallium, a promising candidate for bone pathologies treatment

Strazic, Ivana 09 October 2015 (has links)
En chirurgie reconstructive osseuse les biomatériaux remplacent le tissu osseux manquant et dans le cas de pathologies ils peuvent également délivrer des molécules actives. L’élément semi-métallique, gallium (Ga), est utilisé dans le traitement de différentes pathologies liées à la résorption accélérée de l’os dû à son effet inhibiteur sur les ostéoclastes (cellules résorbantes de l’os). Le Ga peut être incorporé dans la structure des biomatériaux osseux et nous nous sommes intéressés aux propriétés biologiques de ces derniers. In vitro, en présence de Ga nous avons mis en évidence une diminution de la différentiation des ostéoclastes, ainsi qu’une sur-expression de plusieurs marqueurs des ostéoblastes (cellules formatrices d’os). In vivo, le modèle murin de comblement du défaut osseux a montré une augmentation de la quantité de tissu osseux néoformé avec un biomatériau chargé en Ga vs. contrôle. Ces données démontrent que les biomatériaux chargés en Ga sont compatibles avec la survie et la prolifération des cellules osseuses et que le Ga peut améliorer la reconstruction osseuse. D’autre part, étant donné que des effets anti-tumoraux du Ga sont largement décrits, nous avons étudié ces effets sur une lignée cellulaire cancéreuse, choisie pour son affinité pour le tissu osseux. Nous avons montré que le Ga réduit la prolifération et probablement le potentiel tumoral de cette lignée, mais aussi la différentiation ostéoclastique induite par les cellules cancéreuses. Ces effets inhibiteurs observés dans un contexte tumoral indiquent que le Ga est un candidat intéressant pour le couplage avec des biomatériaux destinés au comblement osseux après une résection tumorale. / In bone reconstructive surgery biomaterials commonly replace the missing tissue and in case of pathologies can also serve as vectors for drug delivery. The semi-metallic element gallium (Ga) is used for the treatment of several disorders associated with accelerated bone resorption, due to its inhibitory action on bone-resorbing cells (osteoclasts). Since Ga can be incorporated into the structure of bone biomaterials, we embarked on characterising the biological properties of novel Ga-loaded materials. In vitro, we observed a decrease in osteoclast differentiation and the upregulated expression of several osteoblastic markers (bone-forming cells) in the presence of Ga-loaded biomaterial. In vivo, using a rat bone defect model, we showed an increase in newly formed bone tissue in implants filled with Ga-loaded biomaterial vs. control. Taken together, our data indicate that Ga-loaded biomaterials provide biocompatible substrates allowing bone cells survival and improved bone reconstruction in vivo. Taking into account antitumoral effects of Ga, largely described in literature, we also investigated its impact on a bone metastatic model. Using an aggressive human cancer cell line selected for its ability to invade bone tissue, we showed that Ga could reduce cancer cell proliferation and viability and reverse excessive osteoclastogenesis in bone metastatic environment. Moreover, we demonstrated that Ga modulated the expression of several marker genes hindering the tumour-propagating potential of cancer cells. Thus, due to its inhibitory action on cancer cells, Ga could represent an attractive additive to biomaterials used for tissue reconstruction after tumour resection.
63

Étude des couples chimiokines/récepteurs comme nouvelles cibles thérapeutiques des cancers colorectaux métastasés : études précliniques / The chemokines-chemokine receptors pairs as new therapeutic targets for the metastatic colorectal carcinoma : preclinical studies

Guillemot, Élodie 02 December 2013 (has links)
Avec 42 000 nouveaux cas diagnostiqués en 2012, le cancer colorectal (CCR) représente en France le troisième cancer en termes d’incidence. Les métastases, qui surviennent principalement au niveau du foie et des poumons, en constituent la principale cause de décès. Malgré les progrès récents de la chimiothérapie et des agents ciblés, le taux de survie à 5 ans des patients présentant un CCR métastasé reste faible. Aujourd’hui, la résection chirurgicale est le seul traitement curatif, cependant moins de 20% des patients porteurs de métastases sont opérables. Il existe donc un grand nombre de patients présentant un CCR métastasé pour lequel aucun traitement curatif ne peut être proposé. La formation des métastases à partir d’une tumeur primaire résulte d’une longue série d’étapes séquentielles liées les unes aux autres. L’issue de ce processus dépend à la fois des propriétés intrinsèques des cellules tumorales et de la réponse de l’hôte. Il a récemment été montré que les couples chimiokines/récepteurs interviennent dans le contrôle des différentes étapes de la progression tumorale.Le projet de recherche développé au cours de mon travail de thèse avait pour objectif d’utiliser les chimiokines et leurs récepteurs dans de nouvelles stratégies thérapeutiques pour bloquer et/ou éradiquer les métastases hépatiques et pulmonaires des CCRs. Le travail s’est articulé selon deux axes dans lesquels nous avons montré d’une part que, le blocage du récepteur de chimiokines CXCR7 permet de limiter les métastases pulmonaires de CCRs et d’autre part que, le transfert de gène codant CX3CL1 au niveau du foie entraîne une réponse anti-tumorale efficace dans les métastases hépatiques de CCRs. / With 42 000 newly-diagnosed patients in 2012, the colorectal cancer (CRC) represents the third type of cancer in terms of incidence in France. The leading cause of death from CRC is the development of metastases and these metastases will occur mostly within the liver (50% of the patients) and within the lungs (15%). Despite recent progress, notably in the chemotherapies now used and the targeted agents, the rate of 5-years survival for late stage CRC remains low. Nowadays, the surgical resection is the only curative treatment proposed to patients with metastatic CRC, however less than 20% of them have an operable tumour. There is therefore a high number of patients for whom no cure is currently available. A primary tumour’s dissemination to a second organ is the result of a long process made of numerous cross-linked steps. The final outcome of this process depends on the intrinsic properties of tumour cells as well as the host response. Recently, it has been shown that the chemokine-chemokine receptor pairs (initially described as regulating the leukocyte migration) play crucial roles in the various stages involved in tumour progression. The aim of the research project developed during my PhD was to assess the use of the chemokines and their receptors in new therapeutic strategies to block and/or eradicate the hepatic and pulmonary metastases of CRC. Our work has been organized along two main lines of approach. We have shown that the blockage of the CXCR7 chemokine receptor enables the limitation of the CRC metastases within the lungs and that the CX3CL1 gene transfer into the hepatocytes leads to an efficient anti-tumor response in the CRC metastases within the liver.
64

Rôle du gène de fusion TMPRSS2.ERG dans la formation des métastases osseuses du cancer de la prostate / Role of TMPRSS2.ERG fusion gene in prostate cancer bone metastasis formation

Delliaux, Carine 14 June 2017 (has links)
Les tumeurs locales de la prostate sont associées à une évolution lente et une bonne survie, alors que les stades plus avancés révèlent dans 80% des cas des métastases osseuses incurables. La découverte de gènes de fusion issus de remaniements chromosomiques, tel que TMPRSS2:ERG dans plus de 50% des cas, a ouvert une nouvelle voie dans la compréhension du processus de cancérisation de la prostate. La présence de ce gène de fusion peut être associée à un mauvais pronostic dans de nombreuses études cliniques. Cependant, son rôle précis au cours de la cancérisation et de la progression du cancer de la prostate reste à déterminer. Le gène Erg (Ets related gene) code un facteur de transcription dont l’expression est notamment associée à la mise en place du cartilage, et plus largement du squelette. Ceci suggère un rôle potentiel du gène de fusion impliquant ce facteur, et de ses gènes cibles, dans la formation des métastases osseuses du cancer de la prostate.Pour notre étude, nous avons utilisé des lignées de cellules tumorales prostatiques PC3 et PC3c, exprimant stablement le gène de fusion TMPRSS2:ERG et précédemment établies au laboratoire. Dans un premier temps, en utilisant un modèle d’injections intratibiales chez les souris SCID, nous avons démontré que l’expression ectopique de la fusion améliore la capacité d’induction de lésions ostéocondensantes en inhibant l’ostéolyse dans le modèle PC3 ostéolytique, et en stimulant l’ostéoformation dans le modèle PC3c mixte (ostéolytique et ostéocondensant). Cette expression ectopique de la fusion augmente également l’ostéomimétisme dans les deux modèles cellulaires, c’est-à-dire l’acquisition d’un phénotype semblable aux cellules osseuses leur conférant des avantages de survie et de propagation dans la moelle osseuse. En outre, trois nouveaux gènes cibles de TMPRSS2:ERG ont été mis en évidence : ET-1 (Endothelin-1), stimulant la différenciation ostéoblastique et inhibant la résorption osseuse ostéoclastique, ALPL (Alkaline Phosphatase Liver/Bone/Kidney), marqueur de différenciation des ostéoblastes, et COL1A1 (Collagen Type 1 Alpha 1), composant de la matrice osseuse, témoignant d’un rôle du gène de fusion dans la formation de métastases ostéocondensantes du cancer de la prostate.Par ailleurs, deux autres gènes ont été étudiés, codant soit une protéine impliquée dans la stabilisation de structures particulières appelées invadopodes, soit une protéine impliquée dans le métabolisme des lipides. L’ensemble de ces résultats contribue à mieux comprendre les mécanismes de cancérisation et d’évolution métastatique du cancer de la prostate, en particulier l’influence de l’expression du gène de fusion TMPRSS2:ERG dans les métastases osseuses du cancer de la prostate. / Local prostate cancers are associated with slow progression and good survival, while advanced stages reveal incurable bone metastases in 80% of cases. The discovery of fusion genes resulting from chromosomal rearrangements, such as TMPRSS2:ERG in more than 50% of cases, opened a new way in understanding the process of prostate cancer. The presence of this fusion gene may be associated with poor prognosis in many clinical studies. However, its precise role during cancerization and progression of prostate cancer remains to be determined. The Erg gene (Ets related gene) encodes a transcription factor whose expression is associated in particular with embryonic skeleton development. This suggests a potential role of the fusion gene involving this factor, and its target genes, in the formation of prostate cancer bone metastases.In this study, we used prostate cancer cell lines PC3 and PC3c, stably expressing the TMPRSS2:ERG fusion gene and previously established in the laboratory. First, using a model of intratibial injections in SCID mice, we demonstrated that ectopic expression of the fusion enhances the ability to induce osteoblastic lesions by inhibiting osteolysis in the osteolytic PC3 model, and by stimulating osteoformation in the mixed PC3c model (osteolytic and osteoblastic). This ectopic expression of the fusion also increases osteomimicry in both cell models, meaning the acquisition of a bone-cell-like phenotype which gives them advantages of survival and spread in the bone marrow. In addition, three new TMPRSS2:ERG target genes have been described: ET-1 (Endothelin-1), stimulating osteoblastic differentiation and inhibiting osteoclastic bone resorption, ALPL (Alkaline Phosphatase Liver/Bone/Kidney), a marker of the osteoblasts differentiation, and COL1A1 (Collagen Type 1 Alpha 1), a component of the bone matrix, providing novel insights into the role of the fusion gene in the formation of osteoblastic metastases of prostate cancer.In addition, two other genes have been studied, encoding either a protein involved in the stabilization of particular structures called invadopodia, or a protein involved in lipid metabolism.All these results contribute to decipher the mechanisms of cancerization and metastatic progression of prostate cancer, in particular the influence of the expression of TMPRSS2:ERG fusion gene in prostate cancer bone metastases.
65

CAR-T cell therapy for liver metastases

Lashtur, Nelya 03 November 2016 (has links)
Liver metastases are the most common cause of death in colorectal cancer patients. The standard of care and potential for cure for colorectal liver metastases is resection, but often times disease it too extensive for this treatment. Over the years, cancer research has made way for advances in treating progressive disease through immunotherapy. By genetically modifying an individual’s immune system using virally transduced chimeric antigen receptor T cells (CAR-T), patients are better able to receive exquisitely specific T cells to target specific tumors. Furthermore, selective delivery strategies may enhance efficacy while limiting detrimental, systemic adverse effects. Not only this, CAR-Ts have also lead to complete remission in some liquid tumors while maintaining the potential for remission in solid tumors as well. This literature review takes readers through the emergence of the different generations of CAR-T and the various studies including clinical trials that have demonstrated the safety and efficacy of CAR-T. The second portion of this paper will outline the design for a phase II clinical trial using intrahepatic CAR-T therapy in addition to selective internal radiation therapy (SIRT) for refractory CEA+ colorectal liver metastases. Benefits and limitations of using these therapies are further discussed.
66

MMP-7 is Required for TGF-β and EGF Induced Migration and Invasion in Prostate Cancer Cells

Bolton, Clement, II 08 August 2018 (has links)
Prostate cancer micrometastasis allows cancer cells to vacate their original tumor sites and migrate to distant parts of the body via the bloodstream, lymphatic system, or by direct extension. Cells synthesize and secrete matrix metalloproteinases (MMPs) that degrade proteins of the surrounding extracellular matrix (ECM); thus allowing them to escape into the lymphatic or circulatory systems to invade other tissues. Transforming growth factor β (TGF-β) induces the migration and invasion of cancer cells and the expression of matrix metalloproteinases (MMPs), specifically MMP-2, and -9 in several malignancies. In this study, we examined the role of MMP-7, a known activator of MMP-2 and MMP-9, in TGF-β signaling in cell proliferation, migration, and invasion in prostate cancer cells. Basal expression levels of MMP7 mRNA, protein, and secreted protein were determined using RT-PCR, western blot analysis, and ELISA, respectively. Our data show that MMP7 mRNA and proteins were differentially expressed in several cell line models representing different stages of prostate cancer. TGF-β1 induces MMP-7 gene expression and protein levels 24 and 48 hours after treatment in PC3 cells. Our data also show that TGF-β induces cell migration and invasion in PC3 and E006AA cells; however, the selective knockdown of MMP7 expression using siRNA resulted in a significant decrease in control and TGFβ-induced cell migration and invasion in both PC3 and E006AA cells. MMP-7 knockdown also caused significant reduction in cell proliferation in PC3 cells. Our data suggest that MMP7 is essential for cell migration and invasion in prostate cancer cells indicating that it may be required for TGFβ-induced cancer metastases.
67

Hipervascularidade de metástases hepáticas, detectada através da ressonância magnética, como indicador de progressão da doença em pacientes com câncer de mama / Hypervascularity of liver metastases as detected by MRI- Does it predict disease progression in breast cancer patients?

Larissa Braga 19 January 2004 (has links)
Proposta: O objetivo do presente estudo foi a análise da associação entre a vascularização das metástases hepáticas, detectadas através de exames de ressonância magnética, e a progressão da doença em pacientes com câncer de mama. Casuística e Métodos: Partiu-se do rastreamento de pacientes com câncer de mama dentre todos os pacientes atendidos para exames de ressonância magnética, entre 1995 e 2002, no Hospital da Universidade da Carolina do Norte em Chapel Hill, USA. Foram identificadas 16 pacientes com câncer primário de mama e com metástases hepáticas, com 99 exames de ressonância magnética antes e após a terapia sistêmica. Comparando-se cada exame de ressonância magnética com o seu anterior, a doença das pacientes foi classificada em quatro diferentes status: Resposta Completa, Resposta Parcial, Doença Estável e Doença em Progressão. As metástases hepáticas foram caracterizadas como hipervasculares ou hipovasculares, de acordo com a intensidade do realce durante a fase arterial do exame de ressonância magnética. Estatisticamente, o teste exato de Fisher e o modelo de regressão logística ordinal foram usados para estimar o não ajustamento e o risco de ajustamento entre a presença de metástases hepáticas hipervasculares e a progressão da doença. Resultados: Todas as pacientes eram do sexo feminino, com uma média de idade de 51.5 anos. Na análise não ajustada, a associação entre a presença de hipervascularização nas metástases hepáticas e a progressão da doença foi, de um ponto de vista estatístico, altamente significativa (p< 0,0001). Na análise de regressão logística múltipla, a hipervascularidade de metástases hepáticas foi caracterizada como um fator preditivo independente de progressão da doença. Pacientes com lesões hepáticas hipervasculares apresentaram uma incidência 20,5 vezes maior de progressão da doença, comparadas com pacientes sem hipervascularidade (relação das probabilidades= 20,5; 95% de intervalo de confiança [5,1; 83,5], p < 0,0001). Conclusão: Os resultados de nossa análise mostram evidências de que a progressão da doença pode ser predita através da avaliação da vascularidade das metástases hepáticas pelo exame de ressonância magnética, em pacientes com metástases hepáticas de câncer de mama / Purpose: The aim of the present investigation was to evaluate the association of liver metastases vascularity, as characterized by MR imaging, and disease progression in breast cancer patients. Materials and Methods: Breast cancer patients undergoing liver MR from 1995 through 2002 were extracted from University of North Carolina at Chapel Hill\'s database. Sixteen patients with liver metastases were identified who had 99 MR imaging studies prior and after receiving systemic therapy. Based on comparison of MR imaging with the previous MR examination, disease status of patients were classified as Complete Response, Partial Response, Stable Disease, and Progressive Disease. Liver metastases were characterized as hypervascular or hypovascular based on the degree of enhancement in arterial, portal and interstitial phase after administration of contrast agent. Fisher\'s exact test and ordinal logistic regression models were used to estimate the unadjusted and risk adjusted association between the presence of hypervascular liver metastases and disease progression. Results: All patients were female, and had a median age of 51.5 years old. In unadjusted analyses the association between the presence of hypervascularity of liver metastases and disease progression was highly statistically significant (p < 0.0001). In multiple logistic regression analyses, hypervascularity of liver metastases was found to be an independent predictor of disease progression. Patients with hypervascular liver lesions were 20.5 times more likely to experience disease progression compared with patients without hypervascularity (odds ratio: 20.5; 95% confidence interval [5.1, 83.5], p<0.0001). Conclusion: Our analysis provides suggestive evidence that disease progression can be predicted through MR imaging assessment of the vascularity of liver metastases in breast cancer patients
68

Imunomarcação de micrometástases de neoplasias mamárias espontâneas em linfonodos de cadelas por meio do receptor CD44

Magalhães, Geórgia Modé [UNESP] 01 February 2010 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:27:58Z (GMT). No. of bitstreams: 0 Previous issue date: 2010-02-01Bitstream added on 2014-06-13T20:57:22Z : No. of bitstreams: 1 magalhaes_gm_me_jabo.pdf: 1621150 bytes, checksum: b5a01c9394af10e93a8a4a2595f1190d (MD5) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / As neoplasias mamárias caninas são as mais frequentes nessa espécie e também são comuns em mulheres. Um dos principais fatores prognósticos dessa enfermidade é a presença ou ausência de metástase em linfonodos. A metástase é um mecanismo complexo que envolve vários fatores. Em mulheres sabe-se que a molécula de adesão CD44 está relacionada com invasão e metástase. Este trabalho teve como objetivos: avaliar a imunomarcação de CD44 nas neoplasias mamárias malignas da cadela, com e sem metástase em linfonodos regionais; associá-la como fator prognóstico; na detecção precoce de metástase; relacioná-la com a imunomarcação de MMP-9, E-caderina e VEGF e associar com a sobrevida das cadelas. Compuseram os grupos experimentais, cadelas com tumor mamário, com (Grupo M) ou sem metástase (Grupo N) detectável em linfonodos e um grupo controle composto por tecido mamário normal. Não houve predileção por localização mamária, mas utilizou-se mais as mamas inguinais e linfonodos inguinais. As neoplasias mamárias foram classificadas de acordo com a Organização Mundial de Saúde. Para isso utilizou-se a técnica de imuno-histoquímica, em amostras incluídas em parafina. Para a determinação da porcentagem de imunomarcação considerou-se somente as células epiteliais neoplásicas. Para o anticorpo CD44 contou-se as marcações em linfócitos T nos linfonodos dos dois grupos Observou-se aumento significativo na marcação do CD44 do sítio primário do tumor para a metástase, assim como nas marcações de MMP-9 e E-caderina. As marcações em linfócitos T foram maiores no grupo N e menores no grupo M. O tipo histopatológico mais comum foi o carcinoma simples túbulo papilífero. A raça predominante no grupo das metástases foi Teckel, com idade média de 9,4 anos, e com tempo de sobrevida de sete meses. Concluiu-se... / Mammary neoplasia are the most frequently type of cancer in bitches and also in women. One of the main prognostic factors of this desease is the presence or absent of lymphonodes metastasis. Metastasis is a complex mechanism which involve multiple factors. At women, researchs have shown that the CD44, a adhesion molecule, is related with invasion and metastasis. This research looked for as objectives: Evaluation of CD44 in malignant mammary neoplasia at bitches with and without lymphonodes metastasis; link CD44 and prognosis; CD44 and early detection of metastasis; link CD44 with MMP-9; E-cadherin and VEGF; and associate with the survival of bitches. Experimental groups were arranged with bitches suffering from mammary neoplasia and divided into three groups: Group one(M) were compounded by bitches with visible metastasis in the lymphonodes; Group two(N) were compounded by bitches without visible metastasis in the lymphonodes;Group three or control compounded by bitches with normal mammary tissue. During the research did not have predilection about the mammary localization, despite inguinal breast and lymphonodes were more collected. Mammary neoplasias were classified according to the OMS norms. For this we used the technique of immunohistochemistry in paraffin sections and counted only epithelial cancer cells by method of percentage of labeled cells. Only antibody to CD44 told that the markings on T lymphocytes in lymph nodes of the two groups observed a significant increase in CD44 marking the site of the primary tumor to metastasis, as well as the markings of MMP-9 and E-cadherin. The markings on T lymphocytes were higher in group N and lower in group M. The most common pathological type was the simple tubular papillary carcinoma. The xiii predominant race in the group of metastasis was Daschshund, mean age 9,4 years, and survival... (Complete abstract click electronic access below)
69

Desenvolvimento de conjugados de dextran manose radiomarcados para deteccao de linfonodo sentinela / Development of radiolabled mannose-dextrn conjugates for sentinel lymph node detection

FERNANDEZ NUNEZ, EUTIMIO G. 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:33:13Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:06:12Z (GMT). No. of bitstreams: 0 / Tese (Doutoramento) / IPEN/T / Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP
70

Efeito citogenetico do sup(153) Sm-EDTMP em linfocitos perifericos de pacientes com cancer metastatico

SILVA, MARCIA A. da 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:45:37Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:08:41Z (GMT). No. of bitstreams: 0 / Tese (Doutoramento) / IPEN/T / Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP

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