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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.
21

Stability of protein-based drugs : Herceptin® : a case study

Shropshire, Ian Michael January 2016 (has links)
There is a lack of stability data for in-use parenteral drugs. Manufacturers state a shelf-life of 24 hours for infusions based on microbiological contamination. The lack of data is of particular significance with protein-based drugs where action is determined by their complex structure. A range of techniques are required to assess stability, including biological assessment to support other data. There has been an increase in published data but often the few studies that address in-use stability are incomplete as they do not employ biological assessment to assess potency. Trastuzumab is an antibody-based drug used to treat cancers where the Epidermal Growth Factor Receptor 2 (HER2) is over expressed or over abundant on the cell surface. Trastuzumab infusions have been assigned by the manufacturer to be stable for 24 hours at temperatures not exceeding 30 oC. If stability is shown beyond this point it would enable extended storage and administration. To this end, methods were selected and developed with biological assessment central to the approach to assess clinically relevant infusion concentrations (0.5 mg/mL and 6.0 mg/mL) and a sub-clinical infusion concentration (0.1 mg/mL). This may enhance instability and provide opportunity to study degradation. A Cell Counting Kit CCK8 (Sigma Aldrich) was ultimately adopted as a basis for a colorimetric assay to assess cell viability. Attenuated Total Reflectance Infra-Red Spectroscopy and Size Exclusion Chromatography methods were developed to evaluate secondary structure and aggregation respectively. These methods were applied to a shelf-life study (43 days) as a collaboration with Quality Control North West (NHS) and Clatterbridge Centre for Oncology NHS Foundation Trust, Clatterbridge Hospital. There was no evidence of degradation and no loss efficacy for clinically relevant infusions (0.5 mg/mL and 6.0 mg/mL) over 43 days, whilst the sub-clinical infusions (0.1 mg/mL) developed particles after 7 days of storage between 2 oC and 8 oC. Furthermore, evidence of stability at day 119 gave increased confidence for the data from earlier time points. This work assisted in the shelf-life being recommended to be extended to 28 days for Trastuzumab stored in polyolefin IV bags at concentrations between 0.5 mg/mL and 6.0 mg/mL with 0.9% saline between 2 oC and 8 oC. However, infusions with concentrations below 0.5 mg/mL were not recommended for storage.
22

Trastuzumabe no câncer de mama metastático: uma revisão sistemática da razão custo-efetividade

Andrade, Thays Santos de 21 March 2017 (has links)
Submitted by Biblioteca da Faculdade de Farmácia (bff@ndc.uff.br) on 2017-03-21T18:41:19Z No. of bitstreams: 1 Andrade, Thays Santos de [Dissertação, 2014].pdf: 467886 bytes, checksum: 9f9c6acd0d2516bb655fb10868b2db29 (MD5) / Made available in DSpace on 2017-03-21T18:41:19Z (GMT). No. of bitstreams: 1 Andrade, Thays Santos de [Dissertação, 2014].pdf: 467886 bytes, checksum: 9f9c6acd0d2516bb655fb10868b2db29 (MD5) / O câncer de mama é o tipo que mais acomete as mulheres em todo o mundo. Aproximadamente 30-50% dos pacientes diagnosticados nos estágios iniciais desenvolverão doença metastática, considerada incurável. Nesta fase da doença, as terapias objetivam prolongar a sobrevida e proporcionar controle paliativo dos sintomas. O trastuzumabe, um anticorpo monoclonal dirigido contra o receptor do fator de crescimento epidérmico humano (HER2), vem aumentando as taxas de respostas, sobrevida livre de progressão e/ou sobrevida global no câncer de mama, tendo sido recentemente incorporado pelo Sistema Único de Saúde (SUS) para tratamento de câncer de mama inicial e localmente avançado. O objetivo deste trabalho foi realizar uma revisão sistemática de avaliações de custo-efetividade do trastuzumabe em pacientes com câncer de mama metastático com superexpressão de HER2. Foram realizadas buscas, entre o período de 1998 a 2013, em seis bases de dados eletrônicas, duas ferramentas de busca na internet, além de pesquisa manual de referências. Foram considerados artigos em inglês, espanhol e português, sendo excluídos comentários, editoriais, cartas, estudos de caso, artigos de revisão, revisões sistemáticas e metanálises. As etapas de seleção dos estudos e extração dos dados foram realizadas por dois revisores independentes, e dúvidas foram resolvidas por um terceiro revisor. Os estudos foram avaliados em relação à qualidade seguindo abordagens empregadas por Teerawattananon et al. (2007). A análise dos dados foi realizada a partir da conversão dos custos e de observações das razões incrementais de custo-efetividade do trastuzumabe. Foram identificados 521 estudos, todos em inglês. Destes, descartou-se 455 (294 por não atenderem os critérios da revisão e 161 duplicatas). Sessenta e seis estudos foram incluídos para leitura dos resumos, resultando em 24 para leitura completa do texto. No total, 13 estudos compuseram esta revisão. Os esquemas terapêuticos adotados nas análises de custo-efetividade foram variados. Oito estudos compararam o tratamento do trastuzumabe como 1ª linha para doença metastática e cinco estudos como 2ª linha, sendo que três destes utilizaram o trastuzumabe como comparador na avaliação econômica e não como intervenção. Todos os estudos que utilizaram o trastuzumabe como 2ª linha de tratamento, não consideraram a intervenção custo-efetiva. Em relação à qualidade dos estudos incluídos, estes apresentaram uma boa qualidade, visto que a maioria cumpriu as diretrizes metodológicas de avaliação de custo-efetividade e utilizaram boas evidências na estimativa dos parâmetros. Finalmente, as análises utilizaram diferentes limiares para determinar se o tratamento com o trastuzumabe foi custo-efetivo, bem como diferenças na modelagem dos custos, desfechos e padrões de tratamento. O uso de trastuzumabe, associado ou não, foi custo-efetivo como tratamento de 1ª linha, diferentemente de quando usado como 2ª linha. Foram encontradas diferenças quanto à qualidade dos estudos incluídos. É necessária a realização de novas avaliações de custo-efetividade do trastuzumabe no câncer de mama metastático que, aliadas a fatores administrativos, sociais e políticos, embasem os gestores na tomada de decisão quanto à sua incorporação / Breast cancer is the type that affects more women worldwide. Approximately 30-50 % of patients diagnosed in the early stages will develop metastatic disease, which is considered incurable. At this stage of the disease, therapies aimed prolong survival and provide palliative symptom control. Trastuzumab, a monoclonal antibody targeted to the receptor of the human epidermal growth factor (HER2), has increased response rates, progression-free survival and/or overall survival in breast cancer and has recently been incorporated by the Sistema Único de Saúde (SUS) for treatment of early and locally advanced breast cancer. The aim of this study was to conduct a systematic review of the cost-effectiveness analyses of trastuzumab in patients with metastatic breast cancer overexpressing HER2. Searches were conducted between the period 1998-2013, on six electronic databases, two generic searches on the Internet, as well as manual search of references. We considered articles in English, Spanish and Portuguese, being excluded reviews, editorials, letters, case studies, review articles, systematic reviews and meta-analyses. The stages of study selection and data extraction were performed by two independent reviewers, and doubts were resolved by one third reviewer. Studies were assessed for quality according to approaches employed by Teerawattananon et al (2007). Data analysis was performed from the conversion of the costs and comments of the incremental cost-effectiveness ratios of trastuzumab were made. A quantity of 521 studies, all in English, was identified. Of these, we discarded 455 (294 did not meet the criteria for review and 161 duplicates). Sixty-six studies were included for reading the abstracts, resulting in 24 to read the full text. In total, 13 studies composed this review. The treatment regimens adopted on cost-effectiveness evaluations were varied. Eight studies compared the treatment of trastuzumab as 1st line for metastatic disease and five studies as 2nd line, which three of these used trastuzumab as comparator in the economic evaluation and not as an intervention. All studies using trastuzumab as 2nd line treatment did not consider it as a cost-effective intervention. Regarding the quality of the included studies, they showed a good quality, since most fulfilled the methodological guidelines for assessing costeffectiveness and used good evidence in the estimation of parameters. Finally, the evaluations used different thresholds to determine whether treatment with trastuzumab was cost-effective as well as differences in modeling costs, outcomes and treatment regimens. The use of trastuzumab, alone or associated, was cost-effective as treatment of 1st line, unlike when used as 2nd line. Differences were found in the quality of the included studies. Conducting new cost-effectiveness analyses of trastuzumab in metastatic breast cancer, allied to political, social and administrative factors, which helps decision makers about its incorporation, is required
23

Trastuzumabe no câncer de mama metastático: uma revisão sistemática da razão custo-efetividade

Andrade, Thays Santos de 28 March 2017 (has links)
Submitted by Biblioteca da Faculdade de Farmácia (bff@ndc.uff.br) on 2017-03-28T17:15:31Z No. of bitstreams: 1 Andrade, Thays Santos de [Dissertação, 2014].pdf: 467886 bytes, checksum: 9f9c6acd0d2516bb655fb10868b2db29 (MD5) / Made available in DSpace on 2017-03-28T17:15:31Z (GMT). No. of bitstreams: 1 Andrade, Thays Santos de [Dissertação, 2014].pdf: 467886 bytes, checksum: 9f9c6acd0d2516bb655fb10868b2db29 (MD5) / O câncer de mama é o tipo que mais acomete as mulheres em todo o mundo. Aproximadamente 30-50% dos pacientes diagnosticados nos estágios iniciais desenvolverão doença metastática, considerada incurável. Nesta fase da doença, as terapias objetivam prolongar a sobrevida e proporcionar controle paliativo dos sintomas. O trastuzumabe, um anticorpo monoclonal dirigido contra o receptor do fator de crescimento epidérmico humano (HER2), vem aumentando as taxas de respostas, sobrevida livre de progressão e/ou sobrevida global no câncer de mama, tendo sido recentemente incorporado pelo Sistema Único de Saúde (SUS) para tratamento de câncer de mama inicial e localmente avançado. O objetivo deste trabalho foi realizar uma revisão sistemática de avaliações de custo-efetividade do trastuzumabe em pacientes com câncer de mama metastático com superexpressão de HER2. Foram realizadas buscas, entre o período de 1998 a 2013, em seis bases de dados eletrônicas, duas ferramentas de busca na internet, além de pesquisa manual de referências. Foram considerados artigos em inglês, espanhol e português, sendo excluídos comentários, editoriais, cartas, estudos de caso, artigos de revisão, revisões sistemáticas e metanálises. As etapas de seleção dos estudos e extração dos dados foram realizadas por dois revisores independentes, e dúvidas foram resolvidas por um terceiro revisor. Os estudos foram avaliados em relação à qualidade seguindo abordagens empregadas por Teerawattananon et al. (2007). A análise dos dados foi realizada a partir da conversão dos custos e de observações das razões incrementais de custo-efetividade do trastuzumabe. Foram identificados 521 estudos, todos em inglês. Destes, descartou-se 455 (294 por não atenderem os critérios da revisão e 161 duplicatas). Sessenta e seis estudos foram incluídos para leitura dos resumos, resultando em 24 para leitura completa do texto. No total, 13 estudos compuseram esta revisão. Os esquemas terapêuticos adotados nas análises de custo-efetividade foram variados. Oito estudos compararam o tratamento do trastuzumabe como 1ª linha para doença metastática e cinco estudos como 2ª linha, sendo que três destes utilizaram o trastuzumabe como comparador na avaliação econômica e não como intervenção. Todos os estudos que utilizaram o trastuzumabe como 2ª linha de tratamento, não consideraram a intervenção custo-efetiva. Em relação à qualidade dos estudos incluídos, estes apresentaram uma boa qualidade, visto que a maioria cumpriu as diretrizes metodológicas de avaliação de custo-efetividade e utilizaram boas evidências na estimativa dos parâmetros. Finalmente, as análises utilizaram diferentes limiares para determinar se o tratamento com o trastuzumabe foi custo-efetivo, bem como diferenças na modelagem dos custos, desfechos e padrões de tratamento. O uso de trastuzumabe, associado ou não, foi custo-efetivo como tratamento de 1ª linha, diferentemente de quando usado como 2ª linha. Foram encontradas diferenças quanto à qualidade dos estudos incluídos. É necessária a realização de novas avaliações de custo-efetividade do trastuzumabe no câncer de mama metastático que, aliadas a fatores administrativos, sociais e políticos, embasem os gestores na tomada de decisão quanto à sua incorporação / Breast cancer is the type that affects more women worldwide. Approximately 30-50 % of patients diagnosed in the early stages will develop metastatic disease, which is considered incurable. At this stage of the disease, therapies aimed prolong survival and provide palliative symptom control. Trastuzumab, a monoclonal antibody targeted to the receptor of the human epidermal growth factor (HER2), has increased response rates, progression-free survival and/or overall survival in breast cancer and has recently been incorporated by the Sistema Único de Saúde (SUS) for treatment of early and locally advanced breast cancer. The aim of this study was to conduct a systematic review of the cost-effectiveness analyses of trastuzumab in patients with metastatic breast cancer overexpressing HER2. Searches were conducted between the period 1998-2013, on six electronic databases, two generic searches on the Internet, as well as manual search of references. We considered articles in English, Spanish and Portuguese, being excluded reviews, editorials, letters, case studies, review articles, systematic reviews and meta-analyses. The stages of study selection and data extraction were performed by two independent reviewers, and doubts were resolved by one third reviewer. Studies were assessed for quality according to approaches employed by Teerawattananon et al (2007). Data analysis was performed from the conversion of the costs and comments of the incremental cost-effectiveness ratios of trastuzumab were made. A quantity of 521 studies, all in English, was identified. Of these, we discarded 455 (294 did not meet the criteria for review and 161 duplicates). Sixty-six studies were included for reading the abstracts, resulting in 24 to read the full text. In total, 13 studies composed this review. The treatment regimens adopted on cost-effectiveness evaluations were varied. Eight studies compared the treatment of trastuzumab as 1st line for metastatic disease and five studies as 2nd line, which three of these used trastuzumab as comparator in the economic evaluation and not as an intervention. All studies using trastuzumab as 2nd line treatment did not consider it as a cost-effective intervention. Regarding the quality of the included studies, they showed a good quality, since most fulfilled the methodological guidelines for assessing costeffectiveness and used good evidence in the estimation of parameters. Finally, the evaluations used different thresholds to determine whether treatment with trastuzumab was cost-effective as well as differences in modeling costs, outcomes and treatment regimens. The use of trastuzumab, alone or associated, was cost-effective as treatment of 1st line, unlike when used as 2nd line. Differences were found in the quality of the included studies. Conducting new cost-effectiveness analyses of trastuzumab in metastatic breast cancer, allied to political, social and administrative factors, which helps decision makers about its incorporation, is required
24

ImmunoPet imaging using Zirconium-89 radiolabeled trastuzumab to explore resistance in HER2+/MUC4+ breast cancer

Wimana, Léna 08 December 2015 (has links)
Notre travail s’est focalisé sur l’utilisation du trastuzumab‐immunoPET afin d’étudier et deguider une approche nouvelle visant à surmonter la résistance au médicament trastuzumab,causée par la surexpression de MUC4 dans le cancer du sein.Pour ce faire, nous avons préparé et utilisé du 89Zr‐trastuzumab dans le but de suivresa capacité de liaison au récepteur HER2 ainsi que son accumulation dans des cellulescancéreuses mammaires. Ensuite, nous avons formulé l’hypothèse que des agentsmucolytiques, tels que la N‐Acétylcystéine (NAC), en démêlant les réseaux formés par lesmucines, permettent l’amélioration de la captation du radiotraceur in vitro et in vivo. Eneffet, l’addition du NAC a occasionné une accumulation significative de 89Zr‐trastuzumab,sans altération ni changement de l’affinité de liaison au récepteur. Ceci semble égalementproduire une meilleure sensibilité des imageries PET dans le modèle animal choisi.Dans une seconde étape, nous avons évalué, dans un modèle murin de cancer du seinrésistant au trastuzumab et surexprimant la MUC4, si cette captation accrue se traduit parun bénéfice thérapeutique en utilisant le NAC combiné au trastuzumab. Nous avons obtenuun effet inhibiteur qui réduit de moitié la croissance tumorale, comparable à celui observépour la tumeur mammaire sensible au trastuzumab (implantée dans le même animal).En conclusion, notre étude démontre l’efficacité de l’utilisation de traceurs PETsurtout à visée théranostique, comme c’est le cas du 89Zr‐trastuzumab, pour étudier etévaluer la résistance aux médicaments ciblés apparentés au radiotraceur lui‐même. Ellepropose l’utilisation du NAC pour améliorer l’accessibilité du récepteur pour le radiotraceurainsi que pour le médicament « froid » ouvrant, de ce fait, une perspective vers uneutilisation clinique chez un sous‐type de patientes atteintes d’un cancer du sein. / Doctorat en Sciences biomédicales et pharmaceutiques (Pharmacie) / info:eu-repo/semantics/nonPublished
25

Epigenetic regulation of resistance to treatments in triple negative and HER2+ breast cancer: miRNAs involved

Cabello Navarro, Paula 02 November 2020 (has links)
[ES] El cáncer de mama es el cáncer más común en mujeres en todo el mundo y la principal causa de muerte por cáncer en mujeres junto al cáncer de pulmón. Este cáncer tiene muy buen pronóstico en general, con una supervivencia del 80%. Sin embargo, el pronóstico del cáncer de mama triple negativo es mucho peor, al no conocerse ninguna diana farmacológica y tratarse de forma inespecífica. La metformina, fármaco prescrito para la diabetes, ha mostrado algunos buenos resultados preliminares como potencial terapia. Por otro lado, el principal tratamiento dirigido de las pacientes HER2+ es el trastuzumab, que neutraliza al receptor HER2 amplificado; sin embargo, un elevado número de pacientes desarrollan resistencias al tratamiento. Los microRNAs son pequeños RNAs no codificantes capaces de regular la expresión génica epigenéticamente, y pueden ser secretados de la célula en vesículas llamadas exosomas. El objetivo de este trabajo es abordar estas dos problemáticas en cáncer de mama. Son necesarios estudios de los mecanismos de acción o resistencia de estos fármacos a través de la regulación epigenética por microRNAs. Queremos determinar la relación del miR-26a y sus dianas con el efecto de la metformina en cáncer de mama triple negativo y estudiar las diferencias de expresión de microRNAs que generan resistencias a trastuzumab en cáncer de mama HER2+, así como estudiar su modo de transmisión entre células. Se realizaron ensayos celulares tratando con metformina las líneas MDA-MB-231, MDA-MB-468 y MCF-7 así como sobreexpresando o inhibiendo miR-26a y se midieron sus dianas teóricas por qPCR. Para las líneas HER2+ se realizó un Affymetrix Genechip miRNA 4.0 microarray comparando líneas SKBR-3wt y BT-474wt con sus respectivas líneas con resistencia generada a trastuzumab y HCC-1954 como resistente innata. Se estudiaron los microRNAs más relevantes del array en las líneas celulares y en pacientes y se comprobó su presencia en exosomas, así como el efecto de los exosomas en la transmisión de la resistencia. La sobreexpresión de miR-26a resultó en una reducción en la viabilidad celular que se recuperó parcialmente al inhibirla. E2F3, MCL-1, EZH2, MTDH y PTEN fueron regulados negativamente por miR-26a y la proteína PTEN también se redujo tras la sobreexpresión de miR-26a. El tratamiento con metformina redujo la viabilidad de las células de cáncer de mama, aumentó la expresión de miR-26a y condujo a una reducción en la expresión de BCL-2, EZH2 y PTEN. La inhibición de miR-26a previene parte del efecto en viabilidad de la metformina y la reducción de la expresión de PTEN y EZH2. En las líneas HER2+, miR-23b-3p y miR-146a-5p fueron los principales candidatos extraídos del array. miR-23b-3p inhibió PTEN significativamente en la línea BT-474. miR-146a-5p aumentó la resistencia de las células SKBR-3 al trastuzumab y su inhibición redujo la resistencia de las SKBR-3r. El aumento de miR-146a-5p en SKBR-3wt tuvo un efecto en ciclo celular aumentando la fase S y la G2/M, inhibiendo la expresión de CDKN1A y aumentando la de CCNB1. Los exosomas de las SKBR-3 contenían miR-146a-5p, con mayores niveles en los de las resistentes (exoR). Los exoR aumentaron la resistencia a trastuzumab, la transición epitelio-mesenquimal y la migración al co-cultivarse con SKBR-3wt, y la angiogénesis en las HUVEC. Nuestros resultados sugieren que el efecto de la metformina está mediado por una mayor expresión de miR-26a y reducción de sus dianas, PTEN y EHZ2. Por tanto, el uso de metformina en el tratamiento del cáncer de mama constituye una prometedora potencial terapia. En HER2+, miR-23b parece provocar resistencia a trastuzumab vía PTEN y miR-146a a través del ciclo celular. Además, miR-146a se transmite en exosomas, que son capaces de reducir la sensibilidad al trastuzumab de las células sensibles y aumentar la TEM, migración y angiogénesis. / [EN] Breast cancer is the most common cancer in women worldwide and the leading cause of cancer death in women along with lung cancer. This cancer has a very good general prognosis, with a survival of 80%. However, the prognosis for triple negative breast cancer is much worse, as it has no pharmacological target and treats it nonspecifically. Metformin, a prescribed diabetes drug, has shown some good preliminary results as potential therapy. On the other hand, the main targeted treatment for HER2 + patients is trastuzumab, which neutralizes the amplified HER2 receptor, but a large number of patients experienced resistance to treatment. MicroRNAs are small non-coding RNAs that are part of epigenetics and are capable of regulating gene expression, and which can be secreted from the cell into vesicles called exosomes. The objective of this work is to address these two problems in breast cancer, which need to study the mechanism of action or resistance of these drugs, through the epigenetics of microRNAs. We want to determine the relationship of miR-26a and its targets with the effect of metformin in triple negative breast cancer and to study the differences in the expression of microRNAs that process resistance to trastuzumab in HER2 + breast cancer, as well as to study its mode of transmission between cells. Cellular assays were performed treating the MDA-MB-231, MDA-MB-468 and MCF-7 lines with metformin as well as overexpressing or inhibiting miR-26a, and their theoretical targets were measured by qPCR. For the HER2+ cell lines, an Affymetrix Genechip miRNA 4.0 microarray was performed comparing SKBR-3wt and BT-474wt lines with their respective cell lines with generated resistance to trastuzumab and HCC-1954 as innate resistance. The most relevant microRNAs of the array in cell lines and in patients were studied and their presence in exosomes was verified, as well as the effect of exosomes in the transmission of resistance. The overexpression of miR-26a resulted in a reduction in cell viability that was partially recovered by inhibiting it. E2F3, MCL-1, EZH2, MTDH, and PTEN were down-regulated by miR-26a, and the PTEN protein was also reduced after overexpression of miR-26a. Metformin treatment reduced the viability of breast cancer cells, increased miR-26a expression, and led to a reduction in BCL-2, EZH2, and PTEN expression. Inhibition of miR-26a partly prevents the effect of metformin in viability and the reduction of the expression of PTEN and EZH2. In the HER2+ lines, miR-23b-3p and miR-146a-5p were the main candidates extracted from the array. miR-23b-3p was shown to significantly inhibit PTEN in the BT-474 cell line. miR-146a-5p increased resistance of SKBR-3wt cells to trastuzumab and its inhibition reduced resistance of SKBR-3r. The increase of miR-146a-5p in SKBR-3wt had effect on the cell cycle by increasing the S phase and the G2/M, inhibiting the expression of CDKN1A and increasing CCNB1 levels. Exosomes isolated from SKBR-3 cell lines contained miR-146a-5p, with higher levels in exosomes from the resistant cell line (exoR). The exoR were shown to increase trastuzumab resistance, EMT, and migration when co-cultivated with SKBR-3wt, and angiogenesis when in culture with HUVEC. Our results indicate that metformin effectively reduces breast cancer cell viability and suggests that the effects of the drug are mediated by an increase in miR-26a expression and a reduction of its targets, PTEN and EHZ2. Thus, the use of metformin constitutes a promising potential triple negative breast cancer therapy. In HER2+ breast cancer, miR-23b appears to elicit resistance to trastuzumab via PTEN and miR-146a throughout the cell cycle. Furthermore, miR-146a is transmitted in exosomes, which have been shown to reduce the sensitivity to trastuzumab of sensitive cells and increase EMT, migration, and angiogenesis. / [CA] El càncer de mama és el càncer més comú en dones arreu del món i la principal causa de mort per càncer en dones junt amb el càncer de pulmó. Aquest càncer té molt bon pronòstic en general, amb una supervivència del 80%. No obstant això, el pronòstic del càncer de mama triple negatiu és molt pitjor, al no conèixer-se'n cap diana farmacològica i tractar-se de forma inespecífica. La metformina, fàrmac prescrit per a la diabetis, ha mostrat alguns bons resultats preliminars com a potencial teràpia. D'altra banda, el principal tractament dirigit de les pacients HER2+ és el trastuzumab, que neutralitza el receptor HER2 amplificat; tanmateix, un elevat nombre de pacients desenvolupen resistències al tractament. Els microRNAs són xicotets RNAs no codificants capaços de regular l'expressió gènica epigenèticament, i poden ser secretats de la cèl·lula en vesícules anomenades exosomes. L'objectiu d'aquest treball és abordar aquestes dues problemàtiques en càncer de mama. Són necessaris estudis dels mecanismes d'acció o resistència d'aquests fàrmacs a través de la regulació epigenètica per microRNAs. Volem determinar la relació del miR-26a i les seues dianes amb l'efecte de la metformina en càncer de mama triple negatiu i estudiar les diferències d'expressió dels microRNAs que generen resistències al trastuzumab en càncer de mama HER2+, així com estudiar la seua manera de transmissió entre cèl·lules. Es van realitzar assajos cel·lulars tractant amb metformina les línies MDA-MB-231, MDA-MB-468 i MCF-7 així com sobreexpressant o inhibint miR-26a i es van mesurar les seues dianes teòriques per qPCR. Per a les línies HER2+ es va realitzar un Affymetrix Genechip miRNA 4.0 microarray comparant línies SKBR-3wt i BT-474wt amb les seues respectives línies amb resistència generada a trastuzumab i HCC-1954 com resistent innata. Es van estudiar els microRNAs més rellevants de l'array en les línies cel·lulars i en pacients i es va comprovar la seua presència a exosomes, així com l'efecte dels exosomes en la transmissió de la resistència. La sobreexpressió de miR-26a resultà en una reducció de la viabilitat cel·lular que es recuperà parcialment en inhibir-la. E2F3, MCL-1, EZH2, MTDH i PTEN foren regulats negativament per miR-26a i la proteïna PTEN també es va reduir en sobreexpressar miR-26a. El tractament amb metformina va reduir la viabilitat de les cèl·lules de càncer de mama, va augmentar l'expressió de miR-26a i va conduir a una reducció en l'expressió de BCL-2, EZH2 i PTEN. La inhibició de miR-26a prevé part de l'efecte en la viabilitat de la metformina i la reducció de l'expressió de PTEN i EZH2. En les línies HER2+, miR-23b-3p i miR-146a-5p foren els principals candidats extrets de l'array. miR-23b-3p va inhibir PTEN significativament en la línia BT-474. miR-146a-5p va augmentar la resistència de les cèl·lules SKBR-3 al trastuzumab i la seua inhibició va reduir la resistència de les SKBR-3r. L'augment de miR-146a-5p en SKBR-3wt va tindre un efecte en cicle cel·lular augmentant la fase S i la G2/M, inhibint l'expressió de CDKN1A i augmentant la de CCNB1. Els exosomes de les SKBR-3 contenien miR-146a-5p, amb majors nivells en els de les resistents (exoR). Els exoR van augmentar la resistència a trastuzumab, la transició epiteli-mesenquimal i la migració en co-cultivar-los amb SKBR-3wt, i l'angiogènesi de les HUVEC. Els nostres resultats suggereixen que l'efecte de la metformina està intervingut per una major expressió de miR-26a i reducció de les seues dianes, PTEN i EHZ2. Per tant, l'ús de metformina al tractament de el càncer de mama constitueix una prometedora potencial teràpia. En HER2+, miR-23b sembla provocar resistència a trastuzumab mitjançant PTEN i miR-146a a través del cicle cel·lular. A més, miR-146a es transmet en exosomes, que són capaços de reduir la sensibilitat al trastuzumab de les cèl·lules sensibles i augmentar la TEM, migració i angiogènesi. / Cabello Navarro, P. (2020). Epigenetic regulation of resistance to treatments in triple negative and HER2+ breast cancer: miRNAs involved [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/153807 / TESIS
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Downregulated ATP6V1B1 expression acidifies the intracellular environment of cancer cells leading to resistance to antibody-dependent cellular cytotoxicity / ATP6V1B1の発現低下は癌細胞の細胞内環境を酸性化し、抗体依存性細胞傷害に対する抵抗性をもたらす

Nishie, Mariko 25 January 2021 (has links)
京都大学 / 0048 / 新制・課程博士 / 博士(医学) / 甲第22887号 / 医博第4681号 / 新制||医||1048(附属図書館) / 京都大学大学院医学研究科医学専攻 / (主査)教授 武藤 学, 教授 小川 誠司, 教授 藤田 恭之 / 学位規則第4条第1項該当 / Doctor of Medical Science / Kyoto University / DFAM
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Cardiomyopathy Associated With Targeted Therapy for Breast Cancer

Sivagnanam, Kamesh, Rahman, Zia U., Paul, Timir 01 January 2016 (has links)
Background: Chemotherapeutic agents directed against human epidermal growth factor receptor 2 (HER-2) have significantly improved the prognosis of patients who are positive for this receptor. However, cardiomyopathy remains as a common adverse effect of using these agents. Materials and Methods: Literature search was conducted via PubMed using the keywords of "Trastuzumab Cardiomyopathy," "Lapatinib Cardiomyopathy" and "Pertuzumab Cardiomyopathy," which provided 104 results. These articles were then screened for relevance to the targeted subject based on their title and abstracts. Case reports and articles that were not discussing any aspect of cardiomyopathy secondary to targeted therapy for breast cancer and articles not in English were eliminated. After elimination, a bibliography search among selected articles was done and a total of 46 articles were identified. The collected articles were then meticulously analyzed and summarized. Results: The use of human epidermal growth factor receptor 2 (HER-2) receptor targeted chemotherapy in breast cancer is limited because of a higher incidence (19-22%) of cardiomyopathy. The incidence of cardiomyopathy is not dose dependent and in most cases it is reversible after discontinuation of the drug and treatment with heart failure medications. Severe adverse outcomes including death or permanent disability are rare. Conclusion: HER-2 targeted chemotherapy for breast cancer has a higher incidence of associated reversible cardiomyopathy. Patients should be monitored by serial echocardiography starting at the beginning of the treatment and followed by every 3 months until the completion of chemotherapy. Co-ordination between oncologists and cardiologists is needed to develop evidence-based protocols to prevent, identify, monitor and treat trastuzumab-induced cardiomyopathy.
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Studies for maximizing value of antibody drugs against tumors / 抗がん治療における抗体薬の価値最大化に向けた研究

Kashima(Yamashita), Yoriko 25 November 2014 (has links)
京都大学 / 0048 / 新制・論文博士 / 博士(農学) / 乙第12879号 / 論農博第2806号 / 新制||農||1028(附属図書館) / 学位論文||H26||N4878(農学部図書室) / 31597 / (主査)教授 植田 和光, 教授 植田 充美, 教授 矢﨑 一史 / 学位規則第4条第2項該当 / Doctor of Agricultural Science / Kyoto University / DFAM
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PTEN loss is associated with a poor response to trastuzumab in HER2- overexpressing gastroesophageal adenocarcinoma / PTEN欠失はHER2強発現の胃食道腺癌においてtrastuzumab低感受性に関与する

Deguchi, Yasunori 24 November 2016 (has links)
京都大学 / 0048 / 新制・課程博士 / 博士(医学) / 甲第20052号 / 医博第4160号 / 新制||医||1018(附属図書館) / 京都大学大学院医学研究科医学専攻 / (主査)教授 戸井 雅和, 教授 妹尾 浩, 教授 小川 修 / 学位規則第4条第1項該当 / Doctor of Medical Science / Kyoto University / DFAM
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PTEN is a predictive biomarker of trastuzumab resistance and prognostic factor in HER2-overexpressing gastroesophageal adenocarcinoma / PTENはHER2陽性胃癌・食道腺癌においてTrastuzumab抵抗性を予測するバイオマーカーであり、予後因子である

Yokoyama, Daiju 24 November 2021 (has links)
京都大学 / 新制・課程博士 / 博士(医学) / 甲第23568号 / 医博第4782号 / 新制||医||1054(附属図書館) / 京都大学大学院医学研究科医学専攻 / (主査)教授 武藤 学, 教授 小川 誠司, 教授 戸井 雅和 / 学位規則第4条第1項該当 / Doctor of Medical Science / Kyoto University / DFAM

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