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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.
161

Avaliação do efeito do inibidor de histona deacetilase Panobinostat (LBH589) no metabolismo energético de células derivadas de câncer de pulmão / Evaluation of effects of histone deacetylase inhibitor Panobinostat (LBH589) on the energy metabolism of lung cancer cell lines

Renan Amphilophio Fernandes 09 July 2015 (has links)
Conselho Nacional de Desenvolvimento Científico e Tecnológico / Os mecanismos de ação citotóxica do inibidor de histona deacetilase LBH589 foram investigados em associação com o quimioterápico cisplatina (CDDP) em duas linhagens derivadas de câncer de pulmão de não pequenas células (CPNPC). Os resultados foram analisados em relação ao tipo de morte celular associada às alterações em enzimas relacionadas ao metabolismo energético e a via glicolítica. Para realização do trabalho, foram utilizadas as linhagens tumorais A549 (selvagem para o gene de p53) e Calu-1 (nulo para o gene de p53) tratadas com LBH589 em combinação ou não com CDDP. Foram realizadas curvas de tempo e dose-resposta com as drogas isoladamente pelo ensaio de viabilidade celular (MTT) nas duas linhagens para a escolha das melhores condições para o nosso estudo. As condições dos tratamentos isolados com redução da viabilida celular menores que o IC50 de cada fármaco foram selecionados para realização dos tratamentos combinados. As avaliações de apoptose foram realizadas por citometria de fluxo pelo ensaio de Anexina V/PI, e com a marcação de proteínas por Western Blotting. As proteínas relacionadas a via glicolítica foram avaliadas por Western Blotting e a expressão de RNAm por qPCR. Os resultados demonstraram que o LBH589 combinado a CDDP foi capaz de induzir apoptose em 70% das células (Calu-1) e 54,9% (A549) no tempo de 24 horas, e 90% (calu-1) e 62,1% (A549) em 48 horas, independendo, portanto, do status da p53. Os níveis de expressão de enzimas relacionadas com o metabolismos energético também sofreram alterações nos tratamentos estudados. O LBH589 induziu aumento de cerca de 4x dos níveis de RNAm de HK isoformas I e II em ambas as linhagens. Houve também um aumento na expressão proteica das isoformas de HK I e II. Outras enzimas relacionadas a via glicolítica como PFKP, PKM2 e LDHA foram analisadas e apresentaram redução da expressão proteica, principalmente na presença do LBH589. A combinação da CDDP com LBH589 parece ser promissora para o tratamento de CPNPC induzindo apoptose através de alterações no metabolismo energético tumoral. / The cytotoxic mechanisms of action of the histone deacetylase inhibitor LBH589 was investigated in association with cisplatin in two cell lines derived from non-small lung cancer (NSCLC). The results were analyzed based on the type of the cell death associated with alterations in enzymes related to energy metabolism and glycolytic pathway. To perform the study, we used two non-small lung tumor cell lines, A549 (wild type for the p53 gene) and Calu-1 (null for p53 gene) treated with LBH589 in combination with cisplatin or not. Assays for time and dose responses were performed through the cell viability analysis (MTT) for each drug separately in both cell lines to choose the best conditions for our study. The conditions of isolated treatments with reduced viability lower than the IC50 of each drug were selected for carrying out the combined treatments. Assays for apoptosis detection by flow cytometry were performed by Annexin V / PI, the expression of proteins related to apoptosis by Western Blotting. The expression of glycolytic related proteins were performed by Western blotting and their mRNA expressions by qPCR. The results demonstrated that the combined LBH589 plus CDDP was able to induce apoptosis in 70% of cells -Calu-1- and 54.9% -A549- in 24 hours, and 90% (Calu-1) and 62.1 % (A549) in 48 hours regardless of the p53 status. The expression levels of enzymes related to energy metabolism also presented changes in the studied treatments. The LBH589 increase of about 4x the HK isoforms I and II mRNA levels in both cell lines. There was also an increase in the expression isoforms I and II of HK protein. Other enzymes related to the glycolytic pathway as PFKP, PKM2 and LDHA were analyzed and we observed reduced protein expression, especially in the presence of LBH589. The combination of CDDP with LBH589 appears promising for the treatment of NSCLC inducing apoptosis via alterations in energy metabolism tumor.
162

Cofilina-1 (CFL-1) correlaciona-se à sobrevida mediana em pacientes com carcinoma de pulmão não de pequenas células tratados com radioterapia

Leal, Matheus Hermes January 2016 (has links)
Base teórica: O câncer de pulmão é uma doença com alta incidência e mortalidade, cujo prognóstico permanece discreto apesar do melhor entendimento da doença nas últimas décadas. A radioterapia tem papel terapêutico em todos os estágios da doença. A expressão da cofilina-1, uma proteína relacionada à mobilidade celular, determinou maior radiossensibilidade a células de adenocarcinoma brônquico em estudos in vitro, porém pior sobrevida em estádios iniciais Objetivo: Avaliar se a expressão da cofilina-1 interfere na sobrevida e no controle local em pacientes com câncer de pulmão submetidos a tratamento com radioterapia definitiva Métodos: Foram avaliados pacientes com câncer de pulmão não pequenas células, com estádios I–IV, que receberam radioterapia exclusiva ou combinada com quimioterapia, dirigida à neoplasia brônquica, na unidade de radioterapia do HCPA, nos anos de 2009 a 2015. Todos os pacientes tiveram a expressão de cofilina-1 aferida e foram distribuídos conforme os níveis de expressão de cofilina-1 utilizando-se de protocolo específico. Os prontuários foram avaliados retrospectivamente para calcular a sobrevida mediana. A progressão foi verificada através de avaliação de tomografias de tórax de controle. Resultados: Foram avaliados 45 pacientes neste estudo. A sobrevida mediana de todos os pacientes foi de 11,3 meses e a sobrevida global em 5 anos de 17,3%. Pacientes com expressão média ou alta de cofilina-1 tiveram maior mortalidade quando comparados com pacientes com baixa expressão (respectivamente, HR 1,628, IC95 1,137-8,287 e HR 1,59 IC95 1,105-7,342). Não houve diferença significantemente estatística entre controle local e expressão de cofilina-1. Conclusão: A expressão de cofilina-1 está associada à sobrevida em pacientes com carcinoma brônquico tratados com radioterapia e existe uma tendência a melhor controle local com baixa expressão. Nossos resultados sugerem um novo campo a ser explorado no manejo do carcinoma de pulmão localmente avançado, utilizando-se dos níveis de cofilina-1. / Background: Lung cancer is a disease with high incidence and mortality, whose prognosis remains poor despite a better understanding of the disease in the last decades. Radiotherapy plays a therapeutic role in all stages of disease. The expression of cofilin-1, a protein related to cellular mobility, determined greater radiosensitivity to lung adenocarcinoma cells in in vitro studies, but worse survival at initial stages. Objective: To evaluate if the expression of cofilin-1 modified survival and local control in lung cancer patients submitted to definitive treatment with radiotherapy. Methods: Patients with non-small cell lung cancer with stage IIV who received radiotherapy alone or combined with chemotherapy for lung cancer at the HCPA radiotherapy unit from 2009 to 2015 were evaluated. All patients had the expression of measured cofilin-1 evaluated and were distributed by cofilin-1 expression according to specific protocol. The medical records were retrospectively evaluated to estimate median survival. The progression was verified through evaluation of control chest tomography. Results: 45 patients were assessed in this study. The median survival of all patients was 11.3 months and the 5-year overall survival was 17.3%. Patients with medium or high expression of cofilin-1 had higher mortality rates when compared to patients with low expression (HR, 1,628, CI95, 1,137-8,287 and HR, 1.59, CI95, 1,105-7,342). There was no statistically significant difference between local control and cofilin-1 expression. Conclusion: cofilin-1 expression is associated with survival in patients with lung cancer treated with radiotherapy and there is a tendency for better local control with low CFL1 expression. Our results suggest a new field to be explored in the management of locally advanced lung carcinoma, using cofilin-1 expression levels.
163

Avaliação da atividade do CHY-1, um novo análogo da miltefosina, como potencial inibidor da enzima CTP: fosfoetanolamina-citidilil-transferase, sobre o carcinoma de pulmão de não-pequenas células. / Evaluation of the activity of CHY-1, a novel miltefosine analogue, as a potential CTP: phosphoethanolamine cytidylyltransferase enzyme inhibitor against non-small cell lung cancer.

Sarah Fernandes Teixeira 18 August 2016 (has links)
O câncer de pulmão é um dos mais incidentes e letais, e, assim, a busca de novos fármacos é necessária. Atualmente o desenvolvimento de fármacos conta com abordagens computacionais que otimizam este processo. Dado que a fosfatidiletanolamina desempenha importantes papeis fisiológicos e uma das enzimas envolvidas na sua síntese, a CTP:fosfoetanolamina-citidilil-transferase (Pcyt2) é frequentemente superexpressa em células de câncer de pulmão, no presente trabalho, foram avaliados o potencial terapêutico de CHY-1, um análogo da miltefosina desenvolvido como inibidor da enzima Pcyt2, e os mecanismos inerentes à sua atividade antitumoral. O CHY-1 apresentou citotoxicidade superior ao seu protótipo e a outro inibidor da enzima Pcyt2, a meclizina. Além disso, as células malignas foram mais sensíveis ao CHY-1 do que as células não-tumorigênicas. Em conclusão, o presente trabalho evidencia o potencial do CHY-1 como um inibidor da enzima Pcyt2 e candidato a fármaco com atividade preferencial para câncer de pulmão. / Lung cancer is one of the most incident and lethal cancers, thus, the pursuit for new drugs is necessary. Nowadays, new drugs development has computational tools that improves this process. Once that phosphatidylethanolamine plays several important physiological roles and one of the enzymes of its production pathway, CTP:phosphoethanolamine cytidylyltransferase (Pcyt2), is usually overexpressed in lung cancer cells, therefore, this study aimed was to evaluate the antitumor effects of CHY-1, a miltefosine analogue developed as an inhibitor of Pcyt2 enzyme, and to investigate the mechanisms related to its antitumor action. CHY-1 was more cytotoxicity than its prototype, miltefosine, and was more cytotoxic than another inhibitor Pcyt2 enzyme, meclizine. Morevover, malignant cells were more sensitive to CHY-1 effects than non-tumorigenic cells. In conclusion, this work presents CHY-1 as an inhibitor of Pcyt2 enzyme and new candidate a drug with preferential activity on NSCLC cells.
164

Avaliação de viabilidade, tolerância e segurança da vacina com células dendríticas autológas maduras em pacientes com carcinoma de pulmão não pequenas células avançado = Assessment of feasibility, safety and tolerance of mature autologous dendritic cells vaccine in patients with advanced non-small cell lung carcinoma / Assessment of feasibility, safety and tolerance of mature autologous dendritic cells vaccine in patients with advanced non-small cell lung carcinoma

Perroud Junior, Mauricio Wesley, 1971- 21 August 2018 (has links)
Orientador: Lair Zambon / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Ciências Médicas / Made available in DSpace on 2018-08-21T10:28:19Z (GMT). No. of bitstreams: 1 PerroudJunior_MauricioWesley_D.pdf: 9913138 bytes, checksum: 5dd1ec64b004b6d50e2392e6383c9c98 (MD5) Previous issue date: 2012 / Resumo: Os resultados terapêuticos globais do carcinoma de pulmão não pequenas células em estádio avançado são bem limitados. A imunoterapia com células dendríticas foi desenvolvida como uma nova estratégia para o tratamento de câncer de pulmão. O objetivo deste estudo foi avaliar a viabilidade, segurança e respostas imunológicas em pacientes com carcinoma de pulmão não pequenas células tratados com vacina autóloga de células dendríticas maduras pulsadas com antígenos. Cinco pacientes HLA-A2 com carcinoma de pulmão não pequenas células inoperável (estádio III ou IV) foram selecionados para receber duas doses de 5 x 107 de células dendríticas administradas por vias subcutânea e intravenosa, duas vezes em intervalos de duas semanas. A segurança, tolerabilidade e respostas imunológica e tumoral à vacina foram avaliadas pela evolução clínica e laboratorial, ensaio de linfoproliferação e critérios de RECIST, respectivamente. A dose utilizada para a imunoterapia demonstrou ser segura e bem tolerada. O ensaio de linfoproliferação mostrou uma melhora na resposta imune específica após a imunização, com uma resposta significativa após a segunda dose (p = 0,001). Esta resposta não foi persistente e houve uma tendência à redução após duas semanas da segunda dose da vacina. Dois pacientes apresentaram uma sobrevida quase duas vezes maior que a média esperada e foram os únicos que expressaram os antígenos tumorais HER-2 e CEA Apesar do pequeno tamanho da amostra, os resultados sobre o tempo de sobrevida, resposta imune, segurança e tolerabilidade, combinado com os resultados de outros estudos, são animadores para a condução de um estudo clínico com doses múltiplas em pacientes com câncer de pulmão que foram submetidos a tratamento cirúrgico, seguindo as diretrizes do Cancer Vaccine Clinical Trial Working Group / Abstract: Overall therapeutic outcomes of advanced non-small-cell lung cancer (NSCLC) are poor. The dendritic cell (DC) immunotherapy has been developed as a new strategy for the treatment of lung cancer. The purpose of this study was to evaluate the feasibility, safety and immunologic responses in use in mature, antigen-pulsed autologous DC vaccine in NSCLC patients. Five HLA-A2 patients with inoperable stage III or IV NSCLC were selected to receive two doses of 5x107 DC cells administered subcutaneous and intravenously two times at two week intervals. The safety, tolerability and immunologic and tumor responses to the vaccine were evaluated by the clinical and laboratorial evolution, lymphoproliferation assay and RECIST's criteria, respectively. The dose of the vaccine has shown to be safe and well tolerated. The lymphoproliferation assay showed an improvement in the specific immune response after the immunization, with a significant response after the second dose (p = 0.001). This response was not long lasting and a tendency to reduction two weeks after the second dose of the vaccine was observed. Two patients had a survival almost twice greater than the expected average and were the only ones that expressed HER-2 and CEA together. Despite the small sample size, the results on the survival time, immune response, and safety and tolerability, combined with the results of other studies, are encouraging to the conduction of a large clinical trial with multiples doses in patients with early lung cancer who underwent surgical treatment, following the guidelines of the Cancer Vaccine Clinical Trial Working Group / Doutorado / Clinica Medica / Doutor em Ciências
165

Towards Novel Effective Combination Therapy for KRAS Mutant Non-Small Cell Lung Cancer

Kurim, Sara 12 April 2018 (has links)
Non-small-cell lung cancer (NSCLC) accounts for 80–85% of all lung cancers and is associated with significant mortality. As epidermal-growth-factor receptor (EGFR) is over-expressed in 80-90% of NSCLC, its inhibition via EGFR-Tyrosine Kinase inhibitors (EGFR-TKIs) is a main therapeutic strategy. However, patients with mutations in KRAS are resistant to EGFR-TKIs. A study in mutant KRAS-driven lung cancer in transgenic mice showed that tumor growth was dependent on the activity of focal adhesion kinase (FAK). Therefore, we hypothesized that KRAS-mutant NSCLC will be sensitive to FAK-TKIs and, given known FAK-EGFR cross-talk, FAK inhibition will sensitize KRAS-mutant NSCLC to EGFR-TKIs. We performed cell viability assays of WT versus mutant KRAS NSCLC cell lines following treatment with FAK-TKI alone or in combination with a clinically relevant EGFR-TKI. We found that KRAS-mutant cells were more sensitive to FAK-TKI than KRAS-WT NSCLC. In addition, we found that the combination treatment including FAK and EGFR TKIs resulted in reduced tumor cell viability as compared to treatment with either drug alone. This enhanced anti-tumor response could be due to FAK-TKI’s ability to down-regulate EGFR downstream targets. Our preliminary data suggests that in KRAS-mutant cells the drug combination appears to more effectively inhibit Akt activity than single drug treatment alone. This suggests an enhanced ability to impair cell survival following treatment with the drug combination. We also found that treatment with FAK TKI in KRAS mutant NSCLC cells resulted in increased activation of EGFR which was due in part to modulation of EGFR recycling and production of endogenous EGFR ligands. Thus, the combination of FAK- and EGFR-TKIs may be more effective in KRAS mutant NSCLC as treatment with EGFR-TKI overcomes the unexpected ‘side effect’ of treatment with FAK-TKI, namely activation of the EGFR pathway by this drug. The findings of our study are novel and have uncovered previously unrecognized outcomes of FAK inhibition on EGFR activity. Moreover, our data support the notion that the combination of FAK- and EGFR-TKIs could be an effective treatment for KRAS mutant NSCLC patients.
166

Du rôle de facteurs cliniques, métaboliques, biologiques et thérapeutiques dans le pronostic des patients atteints d'un cancer bronchique non à petites cellules localement avancé, stade III

Berghmans, Thierry 03 March 2009 (has links)
Au travers d’études cliniques et biologiques, de méta-analyses et de revues systématiques de la littérature, nous avons étudié les CBNPC de stade III sur le plan thérapeutique et cherché des facteurs pronostiques pour la survie dans le but d’améliorer la classification internationale et, à terme, de permettre une meilleure prise en charge des patients inclus dans ce groupe hétérogène de tumeurs.<p>Dans le cadre d’essais randomisés, nous avons montré qu’un abord multimodal et multidisciplinaire permettait d’améliorer le pronostic des patients atteints d’un CBNPC de stade III. Le traitement des tumeurs non résécables implique une combinaison de chimiothérapie et de radiothérapie, dont l’administration concomitante doit être proposée aux patients aptes à la tolérer. La chimiothérapie doit être incluse dans le schéma thérapeutique des tumeurs potentiellement résécables. Elle permet une résection chirurgicale complète chez des patients sélectionnés dont la tumeur était initialement non résécable.<p>Nous avons déterminé que des caractéristiques cliniques (l’indice de performance et l’âge), biologiques (les taux sanguins de polynucléaires neutrophiles, d’hémoglobine et de plaquettes, la bilirubinémie) et propres à la tumeur (l’extension locale [T3-4] et ganglionnaire [N3]) avaient une valeur pronostique indépendante pour la survie. Ceci nous a permis d’aboutir à une proposition de modification de la classification internationale concernant les CBNPC de stade III.<p>Bien que pris individuellement, les facteurs biologiques que nous avons étudiés (p53, EGF-R, TTF-1, Mdm2) n’aient pas de valeur pronostique pour la survie, nous avons montré que la combinaison EGF-R+/TTF1- était un facteur pronostique indépendant en analyse multivariée pour la survie spécifique au cancer bronchique.<p>Nous avons finalement évalué le rôle pronostique de la tomodensitométrie par émission de positrons et de la mesure semi-quantitative de captation du 18F-FDG (SUV) sur la survie des patients atteints de CBNPC et montré qu’un SUV élevé était un facteur de mauvais pronostic pour la survie. / Doctorat en Sciences médicales / info:eu-repo/semantics/nonPublished
167

Role of thymidine phosphorylase and Nrf2 transcription factor in non-small cell lung carcinoma growth and angiogenesis / Rôle de la thymidine phosphorylase et du facteur de transcription Nrf2 dans la croissance du carcinome pulmonaire non à petites cellules et dans l'angiogenèse

Tertil, Magdalena 08 January 2013 (has links)
Le facteur de transcription Nrf2 et les enzymes pro-angiogéniques: hème oxygénase (HO-1) et thymidine phosphorylase (TP) sont considérés comme des cibles potentielles pour les traitements combinatoires anticancéreux contre l’angiogenèse. L'objectif de la présente étude était d'examiner les interactions entre ces protéines dans la modulation du potentiel tumorigène et angiogénique de carcinome pulmonaire non à petites cellules (NSCLC). L’augmentation de l’expression de Nrf2 conduit à la réduction de la prolifération cellulaire et à leur capacité de migration, accompagnée d'une expression accrue de microARN suppresseurs de tumeurs ainsi qu’une réduction de l'oncogène miR-378. Ensuite, le rôle de TP dans les cellules NCI-H292 a été étudiée en la surexprimant in vitro (NCI-TP). Ceci a conduit à une atténuation de potentiel tumorigène comme le montre l'inhibition de la prolifération, de la migration et une amélioration concomitante de potentiel angiogénique qui est plus prononcée en hypoxie et en présence de thymidine. In vivo, les tumeurs NCI-TP ont tendance à croître plus rapidement que les témoins et ils sont également mieux oxygénés. Ces tumeurs ont une expression accrue de cytokines pro-inflammatoires IL-1β et IL-6. Nous avons montré pour la première fois que l’enzyme TP peut être régulé par Nrf2 et HO-1 dans les cellules NSCLC, ce qui peut affecter la croissance tumorale par une modulation de l'angiogenèse et de l'expression de facteurs pro-inflammatoires. La corrélation entre l’expression de TP avec celle de l'IL-1β et d'IL-6 a été également confirmée dans les échantillons cliniques de tumeurs issus de patients atteints de NSCLC. L’ensemble de nos résultats montre la potentialité de cibler l’enzyme TP pour le traitement des cancers NSCLC. / Nrf2, heme oxygenase-1 (HO-1) and thymidine phosphorylase (TP) are considered as potential targets for combinatorial anti-cancer therapies. The aim of the study was to investigate the interplay of these proteins in regulation of growth and angiogenesis in non-small cell lung carcinoma (NSCLC) cells NCI-H292. Stable overexpression of Nrf2 (NCI-Nrf2 cell line) resulted in decreased cell proliferation and migration in vitro, upregulation of tumor suppressor microRNAs and downregulation of oncogenic miR-378 and many MMPs. Silencing of HO-1 in NCI-Nrf2 cells partially reversed the effect on MMP-1, MMP-3 and miR-378. NCI-Nrf2 cells exhibited increased expression of proangiogenic factors IL-8, angiopoietin-1 and TP, which was also upregulated in cell overexpressing HO-1. In both models, the effect was TP reversible by siRNA targeted at HO-1 and possibly mediated by modulation of oxidative status of the cell. Moreover, it was observed that overexpression of TP in vitro attenuated proliferation and migration of NSCLC cells, but increased their angiogenic potential. In vivo, NCI-TP tumors tended to grow faster, were better oxygenated and exhibited increased expression of inflammatory cytokines IL-1β and IL-6. Correlation of TP with IL-1β and IL-6 was also confirmed in clinical samples from NSCLC patients. Overall, our results enforce the notion of targeting TP for treatment of NSCLC.
168

A systems biology approach to cancer metabolism

Wright Muelas, Marina January 2016 (has links)
Cancer cells have been known for some time to have very different metabolismas compared to that of normal non proliferating cells. As metabolism is involvedin almost every aspect of cell function, there has been a recent resurgence ofinterest in inhibiting cancer metabolism as a therapeutic strategy. Inhibitors thatspecifically target altered metabolic components in cancer cells are being developedas antiproliferative agents. However, many such inhibitors have not progressedinto the clinic due to limited efficacy either in vitro or in vivo. In this study weexplore the hypothesis that this is often due to the robustness of the metabolicnetwork and the differences between individual cancer cell lines in their metaboliccharacteristics. We take a systems biology approach. We investigate the cellular bioenergetic profiles of a panel of five non-small celllung cancer cell lines before and after treatment with a novel inhibitor of theglutaminase-1 (GLS1) enzyme. Additionally, we explore the effects of this inhibitoron intracellular metabolism of these cell lines as well as on the uptake and secretionof glucose, lactate and amino acids. To be able to do the latter robustly, wehad to modify the experimental assay considerably from procedures that seemto be standard in the literature; using these earlier procedures the metabolicenvironment of the cells was highly variable, leading to misleading results onthe metabolic effects of the inhibitor. We reduced cell density, altered mediumvolume and changed the time-window of the assay. This led to the cells growingexponentially, appearing indifferent to the few remaining changes. In this newassay, the metabolic effects of the glutaminase inhibitor became robust. One of the most significant results of this study is the metabolic heterogeneitydisplayed across the cell line panel under basal conditions. Differences in themetabolic functioning of the cell lines were observed in terms of both theirbioenergetic and metabolic profile. The amount of respiration attributed tooxidative phosphorylation differed between cell lines and respiratory capacity wasattenuated in most cells. However, the rate of glycolysis was similar betweencell lines in this assay. These results suggest that the Warburg effect arisesthrough a greater diversity of mechanisms than traditionally assumed, involvingvarious combinations of changes in the expression of glycolytic and mitochondrialmetabolic enzymes. The effects of GLS1 inhibition on cellular bioenergetics and metabolism alsodiffered between cell lines, even between resistant cell lines, indicating that theremay also be a diversity of resistance mechanisms. The metabolomic response ofcell lines to treatment suggests potential resistance mechanisms through metabolicadaptation or through the prior differences in the metabolic function of resistantcell lines. Part of the metabolome response to GLS1 inhibition was quite specificfor sensitive cells, with high concentrations of IMP as the strongest marker. Our results suggest that the metabolome is a significant player in what determinesthe response of cells to metabolic inhibitors, that its responses differ between cancercells, that responses are not beyond systems understanding, and that thereforethe metabolome should be taken into account in the design of and therapy withanti-cancer drugs.
169

Méta-analyse en réseau cumulative et dynamique / Live cumulative network meta-analysis

Créquit, Perrine 16 November 2016 (has links)
Les revues systématiques sont des outils indispensables à la synthèse des connaissances en évaluation thérapeutique. Il est désormais fréquent que plusieurs traitements soient disponibles pour une même indication. L’objectif des patients et des cliniciens est alors de savoir quels sont, parmi l’ensemble des traitements disponibles, le(s) meilleur(s). Compte tenu de la nécessité de synthétiser les données disponibles pour tous les traitements et de maintenir cette synthèse à jour, notre objectif était d’évaluer les limites du système actuel de synthèse et de développer une méthodologie alternative. Nous avons d’abord évalué la capacité des revues systématiques à prendre en compte l’ensemble des preuves disponibles sur l’effet des multiples traitements. Nous avons utilisé l’exemple des traitements de deuxième ligne du cancer bronchique non à petites cellules métastatique non muté pour EGFR ou de statut inconnu. Nous avons montré que les 29 revues systématiques publiées jusque 2015 sur cette question, considérées collectivement, fournissaient une synthèse fragmentée et non à jour de la preuve disponible. Au moins 40% des 77 essais, des 45 traitements, des 54 comparaisons de traitements et des 28 636 patients n’étaient constamment pas pris en compte dans les revues systématiques. Nous avons discuté les raisons pour lesquelles le système de synthèse des données actuel ne permettait pas de couvrir l’ensemble des données disponibles. Nous avons ensuite développé une nouvelle forme de synthèse de la preuve disponible au cours du temps, la méta-analyse en réseau cumulative et dynamique. Elle consiste à passer d’une série de méta-analyses à une méta-analyse en réseau unique, incluant l’ensemble des traitements disponibles pour une indication donnée, avec une mise à jour du réseau d’essais et de la synthèse des données dès que les résultats d’un nouvel essai deviennent disponibles. Elle débute par une méta-analyse en réseau initiale suivie d’une succession de mises à jour répétées à intervalles réguliers. Nous avons décrit les étapes méthodologiques, et développé le protocole d’une étude de preuve de concept, appliquée aux traitements de deuxième ligne du cancer bronchique non à petites cellules. Enfin, nous avons réalisé la méta-analyse en réseau initiale sur ce même exemple. Nous avons inclus 98 essais randomisés évaluant 60 traitements chez 34 179 patients. Nous avons montré que les traitements par immunothérapie (nivolumab et pembrolizumab) avaient un effet sur la survie globale supérieur aux chimiothérapies et thérapeutiques ciblées actuellement recommandées (nivolumab versus docetaxel HR=0,68 (IC95% 0,55-0,83) ; versus pemetrexed HR=0,65 (0,5-0,83) ; versus erlotinib HR=0,66 (0,51-0,84) and versus gefitinib HR=0,65 (0,51-0,82)). Les résultats étaient similaires pour le pembrolizumab. Pour la survie sans progression, le nivolumab avait aussi un effet supérieur aux quatre traitements recommandés. La méta-analyse en réseau cumulative et dynamique pourrait devenir l’outil permettant de changer de paradigme dans la synthèse des connaissances afin d’améliorer la prise de décision médicale. / Systematic reviews are essential tools to synthesize available evidence for therapeutic evaluation. Multiple treatments are now frequently available for a given condition. Patients and physicians want to know which one is the best among all treatments. Thus we need to retrieve and synthesize all available evidence across all treatments and furthermore to maintain it updated when new evidence and new treatments become available. Our objective was to evaluate the limits of the current ecosystem of evidence synthesis and to develop an alternative methodology. We have first assessed the capacity of systematic reviews to cover all available evidence of multiple treatments. We took the example of second-line treatments of advanced non-small cell lung cancer with EGFR wild-type or unknown status. We have shown that the 29 systematic reviews published in this condition up to 2015, considered collectively, failed to provide a complete and updated synthesis of all available evidence. Almost 40% of the 77 trials, of the 45 treatments, of the 54 treatment comparisons and of the 28,636 patients were always missing from systematic reviews. We have discussed the reasons why the ecosystem of evidence synthesis fails to encompass all available evidence. We then developed a new paradigm to synthesize evidence over time called live cumulative network meta-analysis. This new concept consists in switching from a series of standard meta-analyses to a single network meta-analysis covering all treatments and systematically updated as soon as the results of a new trial become available. Live cumulative network meta-analysis is initiated with a network meta-analysis which is iteratively updated. We have described the methodological steps, developed the protocol of a proof-of-concept study applied to second-line treatments of advanced non-small cell lung cancer. Finally, we have performed the initial network meta-analysis in this condition. We have included 98 trials including 34,179 patients and assessing 60 treatments. We have shown that nivolumab was more effective in term of overall survival compared to docetaxel HR=0.68 (IC95% 0.55-0.83), to pemetrexed HR=0.65 (0.5-0.83), to erlotinib HR=0.66 (0.51-0.84) and to gefitinib HR=0.65 (0.51-0.82). Similar results were found with pembrolizumab. In progression free survival, nivolumab had a more important treatment effect compared to the four recommended treatments. Live cumulative network meta-analysis should become a paradigmatic shift for systematic reviews and meta-analysis in order to improve medical decision making.
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DEVELOPMENT OF MIRIPLATIN-LOADED NANOPARTICLES AGAINST NON-SMALL CELL LUNG CANCER

Yuan, Zhongyue 01 January 2021 (has links)
Lung cancer claims the highest mortality and the second-most estimated new cases among all oncological diseases [1]. Non-small cell lung cancer (NSCLC) accounts for approximately 85% of all newly diagnosed lung cancers [2]. Approximately 40% of newly diagnosed lung cancer patients are stage IV. For stage IIIB/IV NSCLC, cytotoxic combination chemotherapy is standard first-line chemotherapy. A regimen of platinum (cisplatin or carboplatin) plus paclitaxel, gemcitabine, docetaxel, vinorelbine, irinotecan, or pemetrexed is the recommended clinical treatment [3]. Cisplatin is the first-generation platinum-based anti-cancer drug. Although cisplatin is much more effective than other platinum drugs at the same dosage [4], accumulating reports have shown the failure of conventional platinum-based chemotherapy due to various side effects and drug resistance [5]. Miriplatin, a member of platinum drug family, has been approved in Japan in 2009 for transcatheter arterial chemoembolization treatment of hepatocellular carcinoma (HCC) [6]. Miriplatin is a lipophilic platinum drug that contains myristates (14-carbon chains) as leaving groups and diamino cyclohexane as the non-leaving carrier ligand. The application of miriplatin in clinic is limited because it has very poor solubilities both in water and in common organic solvents [7]. The structure of solid tumors and tumor microenvironment (TME) in lung cancer constitute a barrier to the deep penetration of chemotherapy agents, which limits the effectiveness of chemotherapy [8]. Nanoparticles with appropriate properties provide a promising delivery system to overcome the biological and physiochemical barriers that hinder anti-cancer activity [9]. Lipid-based nanoparticles such as liposomes, micelles, and solid lipid nanoparticles (SLNs) can delivery anti-cancer drugs to improve their anti-cancer activities. In this study, we formulated miriplatin into various micelles, liposomes, and SLNs by film-hydration and evaluated their physicochemical properties and anti-cancer activity against NSCLC cells in culture. Miriplatin-loaded formulations with different compositions were successfully prepared by the film-hydration method. Most miriplatin-loaded micelles were more homogeneous and much smaller than miriplatin-loaded liposomes and SLNs. The majority of miriplatin-loaded micelles were about 15 nm in diameter, while SLNs were around 120 nm, and liposomes were about 180 nm. Formulations with a higher molar ratio of PE-PEG2000 had smaller sizes. SLNs loaded with a higher molar ratio of miriplatin in the compositions showed smaller sizes. Inductively coupled plasma mass spectrometry (ICP-MS) and inductively coupled plasma optical emission spectrometry (ICP-OES) techniques were attempted to quantify the platinum element in the formulations. Formulations with a higher molar ratio of PE-PEG2000 had higher recovery of platinum element. Most miriplatin-loaded formulations had higher than 80% platinum recovery. The recovery of intact miriplatin was characterized by HPLC. Miriplatin-loaded micelles had much higher intact miriplatin recovery (about 100%) than SLNs (about 30%). By TEM imaging, the micelles showed the morphology of spherical dots of about 10 nm in diameter while SLNs showed both spherical and rodlike structures of about 120 nm in diameter. The TEM results were consistent with the size and PDI results by the Zetasizer. Three-dimensional multicellular spheroids (3D MCS) of A549 and A549-iRFP cell lines were successfully established as cell culture models to evaluate activity against non-small cell lung cancer. The viability of 3D MCS after 7-days treatment with miriplatin-loaded micelles was about 0%, which was similar to cisplatin. Miriplatin-loaded formulations with a higher molar ratio of PE-PEG2000 in the compositions had higher anti-cancer activity against 3D MCS. The anticancer activity of miriplatin-loaded formulations against 3D MCS was positively associated with the recovery of intact miriplatin from the formulations. The IC50 value of miriplatin-loaded micelles against A549-iRFP 3D MCS was around 25 µM, while that of cisplatin was 84.78 µM. In summary, the reported lipid-based nano-formulations represent a promising delivery system of miriplatin against NSCLC.

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