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Id: biblio-1012010
Autor: Rego, Gabriel Nery de Albuquerque; Mamani, Javier Bustamante; Souza, Taylla Klei Felix; Hospital das ClínicasNucci, Mariana Penteado; Silva, Helio Rodrigues da; Gamarra, Lionel Fernel.
Título: Therapeutic evaluation of magnetic hyperthermia using Fe3O4-aminosilane-coated iron oxide nanoparticles in glioblastoma animal model / Avaliação terapêutica da técnica de magneto-hipertermia utilizando nanopartículas de Fe3O4 recobertas com aminosilana em modelo animal de glioblastoma
Fonte: Einstein (Säo Paulo);17(4):eAO4786, 2019. tab, graf.
Idioma: en.
Resumo: ABSTRACT Objective: To evaluate the potential of magnetic hyperthermia using aminosilane-coated superparamagnetic iron oxide nanoparticles in glioblastoma tumor model. Methods: The aminosilane-coated superparamagnetic iron oxide nanoparticles were analyzed as to their stability in aqueous medium and their heating potential through specific absorption rate, when submitted to magnetic hyperthermia with different frequencies and intensities of alternating magnetic field. In magnetic hyperthermia in vitro assays, the C6 cells cultured and transduced with luciferase were analyzed by bioluminescence in the absence/presence of alternating magnetic field, and also with and without aminosilane-coated superparamagnetic iron oxide nanoparticles. In the in vivo study, the measurement of bioluminescence was performed 21 days after glioblastoma induction with C6 cells in rats. After 24 hours, the aminosilane-coated superparamagnetic iron oxide nanoparticles were implanted in animals, and magnetic hyperthermia was performed for 40 minutes, using the best conditions of frequency and intensity of alternating magnetic field tested in the in vitro study (the highest specific absorption rate value) and verified the difference of bioluminescence before and after magnetic hyperthermia. Results: The aminosilane-coated superparamagnetic iron oxide nanoparticles were stable, and their heating capacity increased along with higher frequency and intensity of alternating magnetic field. The magnetic hyperthermia application with 874kHz and 200 Gauss of alternating magnetic field determined the best value of specific absorption rate (194.917W/g). When these magnetic hyperthermia parameters were used in in vitro and in vivo analysis, resulted in cell death of 52.0% and 32.8%, respectively, detected by bioluminescence. Conclusion: The magnetic hyperthermia was promissing for the therapeutical process of glioblastoma tumors in animal model, using aminosilane-coated superparamagnetic iron oxide nanoparticles, which presented high specific absorption rate.

RESUMO Objetivo: Avaliar o potencial da técnica de magneto-hipertermia utilizando nanopartículas superparamagnéticas de óxido de ferro recobertas com aminosilana em modelo de tumores de glioblastoma. Métodos: As nanopartículas superparamagnéticas de óxido de ferro recobertas com aminosilana foram avaliadas quanto à sua estabilidade em meio aquoso e a seu potencial de aquecimento pela taxa de absorção específica, quando submetidas à magneto-hipertermia, com diferentes frequências e intensidades de campo magnético alternado. Nos ensaios de magneto-hipertermia in vitro, as células C6 cultivadas e transduzidas com luciferase foram avaliadas por bioluminescência na presença/ausência do campo magnético alternado, como também com e sem nanopartículas superparamagnéticas de óxido de ferro recobertas com aminosilana. No estudo in vivo, a medida de bioluminescência foi adquirida no 21º dia após indução do glioblastoma com células C6 nos ratos. Após 24 horas, as nanopartículas superparamagnéticas de óxido de ferro recobertas com aminosilana foram implantadas no animal, tendo sido realizada a magneto-hipertermia por 40 minutos, nas melhores condições de frequência e intensidade de campo magnético alternado testado no estudo in vitro (maior valor da taxa de absorção específica); foi verificada a diferença do bioluminescência antes e após a magneto-hipertermia. Resultados: As nanopartículas superparamagnéticas de óxido de ferro recobertas com aminosilana se mostraram estáveis, e sua capacidade de aquecimento aumentou com o incremento da frequência e da intensidade de campo magnético alternado. A aplicação da magneto-hipertermia, com 874kHz e 200 Gauss do campo magnético alternado, determinou o melhor valor da taxa de absorção específica (194,917W/g). Quando utilizados, estes parâmetros de magneto-hipertermia in vitro resultaram em morte celular de 52,0% e in vivo de 32,8% por bioluminescência. Conclusão: A técnica de magneto-hipertermia foi promissora para o processo terapêutico de tumores de glioblastoma no modelo animal utilizando as nanopartículas superparamagnéticas de óxido de ferro recobertas com aminosilana recobertas com aminosilana, que apresentaram alta taxa de absorção específica.
Descritores: Neoplasias Encefálicas/terapia
Compostos Férricos/uso terapêutico
Glioblastoma/terapia
Magnetoterapia/métodos
Nanopartículas de Magnetita/uso terapêutico
Hipertermia Induzida/métodos
-Valores de Referência
Fatores de Tempo
Temperatura Corporal
Compostos Férricos/química
Reprodutibilidade dos Testes
Análise de Variância
Resultado do Tratamento
Ratos Wistar
Linhagem Celular Tumoral
Modelos Animais de Doenças
Nanopartículas de Magnetita/química
Medições Luminescentes
Limites: Animais
Masculino
Tipo de Publ: Estudo de Avaliação
Responsável: BR1.1 - BIREME


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Id: biblio-1056032
Autor: Mamani, Javier Bustamante; Marinho, Bruna Souto; Rego, Gabriel Nery de Albuquerque; Hospital das ClínicasNucci, Mariana Penteado; Alvieri, Fernando; Santos, Ricardo Silva dos; Ferreira, João Victor Matias; Oliveira, Fernando Anselmo de; Gamarra, Lionel Fernel.
Título: Magnetic hyperthermia therapy in glioblastoma tumor on-a-Chip model / Terapia de magneto-hipertermia no modelo de tumor de glioblastoma on-a-Chip
Fonte: Einstein (Säo Paulo);18:eAO4954, 2020. graf.
Idioma: en.
Projeto: CNPq; . FAPESP.
Resumo: ABSTRACT Objective: To evaluate the magnetic hyperthermia therapy in glioblastoma tumor-on-a-Chip model using a microfluidics device. Methods: The magnetic nanoparticles coated with aminosilane were used for the therapy of magnetic hyperthermia, being evaluated the specific absorption rate of the magnetic nanoparticles at 300 Gauss and 305kHz. A preculture of C6 cells was performed before the 3D cells culture on the chip. The process of magnetic hyperthermia on the Chip was performed after administration of 20μL of magnetic nanoparticles (10mgFe/mL) using the parameters that generated the specific absorption rate value. The efficacy of magnetic hyperthermia therapy was evaluated by using the cell viability test through the following fluorescence staining: calcein acetoxymethyl ester (492/513nm), for live cells, and ethidium homodimer-1 (526/619nm) for dead cells dyes. Results: Magnetic nanoparticles when submitted to the alternating magnetic field (300 Gauss and 305kHz) produced a mean value of the specific absorption rate of 115.4±6.0W/g. The 3D culture of C6 cells evaluated by light field microscopy imaging showed the proliferation and morphology of the cells prior to the application of magnetic hyperthermia therapy. Fluorescence images showed decreased viability of cultured cells in organ-on-a-Chip by 20% and 100% after 10 and 30 minutes of the magnetic hyperthermia therapy application respectively. Conclusion: The study showed that the therapeutic process of magnetic hyperthermia in the glioblastoma on-a-chip model was effective to produce the total cell lise after 30 minutes of therapy.

RESUMO Objetivo: Avaliar a terapia de magneto-hipertermia em modelo de tumor de glioblastoma on-a-Chip. Métodos: As nanopartículas magnéticas recobertas com aminosilana foram utilizadas para a terapia da magneto-hipertermia, sendo avaliada a taxa de absorção específica das nanopartículas magnéticas em 300 Gauss e 305kHz. Uma pré-cultura de células C6 foi realizada e, seguidamente, foi feito o cultivo das células 3D no chip. O processo de magneto-hipertermia no chip foi realizado após administração de 20μL de nanopartículas magnéticas (10mgFe/mL), utilizando os parâmetros que geraram o valor da taxa de absorção específica. A eficácia da terapia de magneto-hipertermia foi avaliada pela viabilidade celular por meio dos corantes fluorescentes acetoximetiléster de calceína (492/513nm), para células vivas, e etídio homodímero-1 (526/619nm), para células mortas. Resultados: As nanopartículas magnéticas, quando submetidas ao campo magnético alternado (300 Gauss e 305kHz), produziram um valor médio da taxa de absorção específica de 115,4±6,0W/g. A cultura 3D das células C6 avaliada por imagem de microscopia de campo claro mostrou a proliferação e a morfologia das células antes da aplicação da terapia de magneto-hipertermia. As imagens de fluorescência mostraram diminuição da viabilidade das células cultivadas no organ-on-a-Chip em 20% e 100% após 10 e 30 minutos, respectivamente, da aplicação da terapia de magneto-hipertermia. Conclusão: O processo terapêutico da magneto-hipertermia no modelo de tumor glioblastoma on-a-chip foi eficaz para produzir lise total das células após 30 minutos de terapia.
Descritores: Glioblastoma/terapia
Técnicas de Cultura de Células/métodos
Dispositivos Lab-On-A-Chip
Nanopartículas de Magnetita/uso terapêutico
Hipertermia Induzida/métodos
-Temperatura
Fatores de Tempo
Sobrevivência Celular
Reprodutibilidade dos Testes
Resultado do Tratamento
Linhagem Celular Tumoral
Campos Magnéticos
Fluorescência
Limites: Animais
Ratos
Tipo de Publ: Estudo de Avaliação
Responsável: BR1.1 - BIREME


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Id: biblio-899743
Autor: Villalpando-Guzmán, Sergio; Vázquez-Quiñones, Carlos Ramón; Natividad-Bonifacio, Iván; Curiel-Quesada, Everardo; Quiñones-Ramírez, Elsa Irma; Vázquez-Salinas, Carlos.
Título: Frecuencia, susceptibilidad antimicrobiana y patrón de adherencia de Salmonella enterica aislada de carne de pollo, res y cerdo de la Ciudad de México / Frequency, antimicrobial susceptibility and adherence patterns of Salmonella enterica isolated from chicken meat, beef and pork from Mexico City
Fonte: Rev. chil. infectol;34(5):458-466, oct. 2017. tab, graf.
Idioma: es.
Resumo: Resumen Introducción: Los alimentos de origen animal frecuentemente están implicados en brotes de salmonelosis. Objetivo: Evaluar la frecuencia de Salmonella enterica en carnes molidas de pollo, res y cerdo (un total de 2.592 muestras) obtenidas de mercados sobre ruedas y supermercados de la Delegación Iztapalapa en la Ciudad de México, determinar la susceptibilidad antimicrobiana y efectuar ensayos de adherencia en las cepas aisladas. Métodos: El aislamiento de S. enterica se hizo de acuerdo a la BAM-FDA, la susceptibilidad antimicrobiana de acuerdo con CLSI y el ensayo de adherencia en células HEp-2 conforme a Baffone y cols., 2001. Resultados: Salmonella enterica fue aislada en 511 del total de muestras analizadas (19,7%), de las cuales 244 (47,7%), 152 (29,7%) y 115 (22,5%) correspondieron a carne molida de pollo, res y cerdo, respectivamente. La mayor frecuencia de resistencia de S. enterica a antimicrobianos fue a ampicilina y cloranfenicol en pollo, perfloxacina y ampicilina en res y carbenicilina, ampicilina, cloranfenicol, cefotaxima y perfloxacina en cerdo. Noventa por ciento de las cepas mostraron un patrón de adherencia agregativo. Conclusión: La frecuencia de S. enterica en productos cárnicos es alta, por lo que es importante la adecuada cocción de la carne para disminuir el riesgo de una salmonelosis.

Background: Food of animal origin is often involved in salmonellosis outbreaks. Aim: To evaluate the frequency of Salmonella enterica in chicken, beef and pork ground meat (a total of 2,592 samples) obtained from travelling markets and supermarkets at the Iztapalapa area of Mexico City, in order to determine the antimicrobial susceptibility and adherence capacity of isolated strains. Methods: Isolation of S. enterica was carried out according to the BAM-FDA, the microbial susceptibility according with CLSI and adherence assay on HEp-2 cell line according with Baffone et al., 2001. Results: S. enterica was isolated from 511 of all the analyzed samples (19.7%), from which 244 (47.7%), 152 (29.7%) and 115 (22.5%) corresponded to chicken, beef and pork ground meat, respectively. The highest frequency of resistance of S. enterica to antimicrobials was to ampicillin and chloramphenicol in chicken, perfloxacin and ampicillin in beef and carbenicillin, ampicillin, chloramphenicol, cefotaxime and perfloxacin in pork. Ninety percent of the strains showed an aggregative adherence pattern on HEp-2 cells. Conclusion: The frequency of S. enterica on meat products is high, which is the reason why a proper cooking of these ground meats is important in order to reduce the risk of acquiring salmonellosis.
Descritores: Aves Domésticas/microbiologia
Aderência Bacteriana/fisiologia
Salmonella enterica/isolamento & purificação
Salmonella enterica/efeitos dos fármacos
Carne Vermelha/microbiologia
Antibacterianos/farmacologia
-Suínos
Fatores de Tempo
Resistência Microbiana a Medicamentos
Bovinos
Testes de Sensibilidade Microbiana
Galinhas
Linhagem Celular Tumoral/microbiologia
Sorogrupo
Microbiologia de Alimentos
México
Limites: Animais
Responsável: CL1.1 - Biblioteca Central


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Id: biblio-1045621
Autor: Lowe, HIC; Toyang, NJ; Bryant, J.
Título: In vitro and In vivo anti-cancer effects of Tillandsia recurvata (Ball Moss) from Jamaica / Efectos Anticancerosos In vitro e In vivo de la Tillandsia recurvata (Bola de Musgo) de Jamaica
Fonte: West Indian med. j;62(3):177-180, Mar. 2013. ilus.
Idioma: en.
Resumo: OBJECTIVE: Tillandsia recurvata, also commonly known as Ball Moss, is endemic to Jamaica and some parts of the Caribbean and South America. The plant, despite being reported to be used in folk medicine, had not previously been evaluated for its anti-cancer potential. The aim of this study was to evaluate the anti-cancer activity of Ball Moss. METHODS: The anti-proliferation activity of the crude methanolic extract of the T recurvata was evaluated in vitro in five different histogenic cancer cell lines (prostate cancer - PC-3, breast cancer, Kaposi sarcoma, B-16 melanoma and a B-cell lymphoma from a transgenic mouse strain) using the trypan blue assay. The crude extract was also evaluated in vivo in tumour-bearing mice. Immunohistochemistry staining with Apoptag was used for histology and determination of apoptosis. RESULTS: The crude methanolic extract of T recurvata demonstrated anti-proliferation activity against all the cell lines, killing > 50% of the cells at a concentration of 2.5 µg/ml. Kaposi sarcoma xenograft tumours were inhibited by up to 75% compared to control in the in vivo study (p < 0.05). There was evidence of DNA fragmentation and a decrease in cell viability on histological studies. The methanolic extract showed no toxic effect in the mice at a dose of 200 mg/kg. CONCLUSIONS: Our data suggest that T recurvata has great potential as an anti-cancer agent and that one of its mechanisms of cell kill and tumour inhibition is by the induction of apoptosis.

OBJETIVO: La Tillandsia recurvata, también conocida como bola de musgo, es endémica en Jamaica, así como en algunas partes del Caribe y América del sur. Si bien se había reportado su uso como parte de la medicina popular, esta planta no había sido evaluada previamente en relación con su potencial para la lucha contra el cáncer. El objetivo de este estudio fue evaluar la actividad anticancerígena de la bola de musgo. MÉTODOS: La actividad antiproliferativa del extracto metanólico crudo de la T recurvata, fue evaluada in vitro en cinco líneas celulares diferentes de cáncer histogenético (cáncer de próstata - PC-3, cáncer de mama, sarcoma de Kaposi, melanoma B-16 y un linfoma de células B de una cepa de ratón transgénico) usando el ensayo con azul de tripano. El extracto crudo también se evaluó in vivo en ratones portadores de tumor. La tinción inmunohistoquímica con ApopTag fue utilizada para la histología y determinación de la apoptosis. RESULTADOS: El extracto metanólico crudo de T recurvata demostró la actividad proliferativa frente a todas las líneas celulares, matando > 50% de las células a una concentración de 2,5 µg/ml. Los tumores de xenoinjerto de sarcoma de Kaposi fueron inhibidos hasta un 75% en comparación con el control en el estudio in vivo (p < 0.05). Hubo evidencia de fragmentación de DNA y una disminución en la viabilidad celular en los estudios histológicos. El extracto metanólico no mostró ningún efecto tóxico en los ratones a dosis de 200 mg/kg. CONCLUSIONES: Nuestros datos sugieren que la T recurvata tiene gran potencial como agente anticanceroso, y que uno de sus mecanismos de inhibición de tumores y muerte de las células tiene lugar mediante la inducción de la apoptosis.
Descritores: Extratos Vegetais/farmacologia
Apoptose/efeitos dos fármacos
Tillandsia
Proliferação de Células/efeitos dos fármacos
Antineoplásicos/farmacologia
-Neoplasias da Próstata
Sarcoma de Kaposi
Mama
DNA/efeitos dos fármacos
Sobrevivência Celular/efeitos dos fármacos
Linfoma de Células B
Ensaios Antitumorais Modelo de Xenoenxerto/métodos
Linhagem Celular Tumoral
Jamaica
Melanoma
Camundongos
Neoplasias
Limites: Humanos
Animais
Masculino
Feminino
Responsável: BR1.1 - BIREME


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Id: lil-794669
Autor: Zhu, Yong-tong; Pang, Shi-yu; Luo, Yang; Chen, Wei; Bao, Ji-ming; Tan, Wan-long.
Título: A modified method by differential adhesion for enrichment of bladder cancer stem cells
Fonte: Int. braz. j. urol;42(4):817-824, July-Aug. 2016. tab, graf.
Idioma: en.
Projeto: Education Department in Guangdong Province; . Southern Medical University.
Resumo: ABSTRACT Purpose: In a previous study the vaccine was effective against bladder cancer in a mouse model. However, a small portion of tumors regrew because the vaccine could not eliminate bladder cancer stem cells (CSCs). In this study, we showed a modified method for the isolation of bladder CSCs using a combination of differential adhesion method and serum-free culture medium (SFM) method. Materials and Methods: Trypsin-resistant cells and trypsin-sensitive cells were isolated from MB49, EJ and 5637 cells by a combination of differential adhesion method and SFM method. The CSCs characterizations of trypsin-resistant cells were verified by the flow cytometry, the western blotting, the quantitative polymerase chain reaction, the resistance to chemotherapy assay, the transwell assay, and the tumor xenograft formation assay. Results: Trypsin-resistant cells were isolated and identified in CSCs characters, with high expression of CSCs markers, higher resistance to chemotherapy, greater migration in vitro, and stronger tumorigenicity in vivo. Conclusion: Trypsin-resistant cells displayed specific CSCs properties. Our study showed trypsin-resistant cells were isolated successfully with a modified method using a combination of differential adhesion method and SFM method.
Descritores: Células-Tronco Neoplásicas/citologia
Neoplasias da Bexiga Urinária/patologia
Tripsina/farmacologia
Adesão Celular/efeitos dos fármacos
Separação Celular/métodos
Técnicas de Cultura de Células/métodos
-Células-Tronco Neoplásicas/química
Biomarcadores Tumorais
Diferenciação Celular
Meios de Cultura Livres de Soro
Vacinas Anticâncer/imunologia
Linhagem Celular Tumoral
Reação em Cadeia da Polimerase em Tempo Real
Citometria de Fluxo
Camundongos Nus
Limites: Animais
Camundongos
Responsável: BR1.1 - BIREME


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Id: biblio-1280866
Autor: Cassinela, Edson Kuatelela.
Título: Papel das vesículas extracelulares secretadas por adenocarcinomas gástricos na resposta ao tratamento quimioterápico / Role of extracellular vesicles secreted by gastric adenocarcinomas in response to chemotherapy.
Fonte: São Paulo; s.n; 2018. 125 p. ilust, tabelas, quadros.
Idioma: pt.
Tese: Apresentada a Fundação Antônio Prudente para obtenção do grau de Doutor.
Resumo: O adenocarcinoma gástrico (AdG) é a terceira causa mais comum de morte por câncer no mundo e um dos tumores com maior índice de mortalidade no Brasil. Estes tumores aparecem em terceiro lugar na incidência entre homens e em quinto nas mulheres. A quimioterapia neoadjuvante (QT) com 5-fluorouracil (5-FU) pode melhorar a ressecabilidade e a sobrevida dos pacientes com AdG, porém sua eficácia está limitada pela resistência à droga. Apenas pacientes que respondem a esta terapia com toxicidade tolerável são potencialmente beneficiados, entretanto não é possível identificar e separar clinicamente estes indivíduos. Assim, identificar marcadores preditivos de resposta para selecionar os pacientes que se beneficiariam deste tratamento é relevante. Vesículas extracelulares (VEs) são componentes secretados pelas células incluindo células tumorais, cujo conteúdo é regulado e composto por moléculas que podem ter uma miríade de funções locais e a distância. Muitas destas moléculas podem ser também usadas como biomarcadores séricos por conterem informações importantes sobre o tumor. Desta forma, este trabalho tem como objetivo identificar marcadores de resistência a 5-FU em VEs secretadas por linhagens celulares humanas de câncer gástrico e avaliar o papel das VEs na quimioresistência. Para tanto, foram geradas células de AdG derivadas da linhagem AGS, resistentes a 5-FU (rAGS_FU) de onde foram isoladas, quantificadas e caracterizadas VEs. Células rAGS-FU secretam cerca de 2 vezes mais VEs que as células parentais (AGS), entretanto a distribuição destas por tamanho é semelhante. As células rAGS_FU apresentaram maior proliferação, capacidade de formação de colônias e invasão que as células AGS. Interessantemente, as VEs provenientes de células resistentes a 5-FU, rAGS_FU, são capazes de transferir à células AGS os fenótipos de resistência ao quimioterápico bem como um aumento na capacidade de formação de colônias e invasão. As células AGS que se tornam resistentes ao tratamento não têm este fenótipo revertido pela remoção das VEs da células resistentes nem pelo tratamento com VEs de células AGS parental, indicando que o fenótipo de resistência adquirido após o tratamento é irreversível, pelo menos pelo período estudado. O conteúdo proteico das VEs das células AGS e rAGS_FU e suas respectivas VEs foi comparado por proteômica. Nessa abordagem foram identificadas 1.915 proteínas nas células e 1.638 proteínas em VEs das quais 309 proteínas eram diferencialmente expressas em células e 66 em VEs. Entre as proteínas com expressão diferencial entre as duas células e também nas suas respectivas VEs, selecionamos e validamos por western blotting a proteina fascina. Esta parece ser um potencial candidato a biomarcador de resistência a 5-FU uma vez que sua expressão é indetectável na célula AGC e suas VEs e altamente expressa nas células rAGS_FU e suas vesículas. A fascina é uma proteína do citoesqueleto com um papel chave nas interações célula-célula, adesão e motilidade celulares e é associada a agressividade tumoral. Estes dados apontam o papel das VEs nos mecanismos relacionados à resistência a 5-FU em células de AdG e sugerem que fascina possa estar associada ao mecanismo de resistência a este quimioterápico e que também seja um potencial biomarcador deste fenótipo

Gastric adenocarcinoma (GAd) is the third most common cause of cancer related death worldwide, and one of the tumors with the highest mortality rates in Brazil. In men, this cancer ranks the third most common cancer, while in women, it ranks fifth. 5-fluorouracil (5-FU) based neoadjuvant chemotherapy can improve tumor resectability and patient's survival rates. Its effectiveness however, is limited by drug resistance. Thus, an effort to identify predictive markers of response to neoadjuvant therapy and select patients who could benefit from this treatment is relevant. One such approach could be to use contents of extracellular vesicles (EVs). EVs are components secreted by cells including tumor cells, whose contents are composed of molecules that can have a myriad of local and distance functions and many of these molecules can also be used as serum biomarkers since they contain important information about the tumor. This work aims to identify 5-FU resistance markers in EVs secreted by human gastric cancer cell line and to evaluate the role of EVs in chemoresistance. GAd cells resistant to 5-FU (rAGS_FU) were generated from the AGS cell line and EVs secreted by rAGS_FU cells and parental AGS cells were isolated, quantified and characterized. Our results showed that AGS_FU cells secrete about 2 times more EVs than parental AGS cells, however their size distribution is similar. The resistant rAGS_FU cells showed higher proliferation rates, capacity of colony formation and invasion properties. Interestingly, EVs from 5-FU resistant cells, rAGS_FU, are able to transfer to the AGS cells the phenotypes of resistance to chemotherapy as well as an increase in the capacity of colony formation and invasion. AGS cells that become resistant to treatment do not have this phenotype reversed by removal of the EVs from the resistant cells or by treatment with EVs from parental AGS cells, indicating that the resistance phenotype acquired after treatment is irreversible, at least for the period studied. The protein content of the AGS and rAGS_FU cells and their respective EVs was compared by proteomics. In this approach, 1,915 proteins were identified in cells and 1,638 proteins in EVs of which 309 proteins were differentially expressed in cells and 66 in EVs. Among the proteins with differential expression between the two cells and also in their respective EVs, we selected and validated by western blotting the protein fascin. Fascin protein appears to be a potential candidate for biomarker of 5-FU resistance since its expression is undetectable in AGS cells and their EVs and highly expressed in rAGS_FU cells and their vesicles. Fascin is a cytoskeletal protein with a key role in cellcell interactions, cell adhesion and motility and is associated with tumor aggressiveness. These data point to the role of EVs in the mechanisms related to 5-FU resistance in GAd cells and suggest that fascin may be associated with the mechanism of resistance to this chemotherapeutic agent and that it is also a potential biomarker of this phenotype
Descritores: Fenótipo
Neoplasias Gástricas/tratamento farmacológico
Biomarcadores
Terapia Neoadjuvante
Linhagem Celular Tumoral
Vesículas Extracelulares
-Preparações Farmacêuticas
Proteômica/métodos
Limites: Humanos
Masculino
Responsável: BR30.1 - Biblioteca
BR30.1


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Id: biblio-892928
Autor: Yang, Zhi-Gang; Ma, Xu-Dong; He, Zhao-Hui; Guo, Ying-xin.
Título: miR-483-5p promotes prostate cancer cell proliferation and invasion by targeting RBM5
Fonte: Int. braz. j. urol;43(6):1060-1067, Nov.-Dec. 2017. graf.
Idioma: en.
Resumo: ABSTRACT Objective: miR-483-5p has been identified as a miRNA oncogene in certain cancers. However, its role in prostate cancer has not been sufficiently investigated. In this study, we investigated the role of miR-483-5p in prostate cancer and examined RBM5 regulation by miR-483-5p. Material and methods: Expression levels of miR-483-5p were determined by quantitative real-time PCR. The effect of miR-483-5p on proliferation was evaluated by MTT assay, cell invasion was evaluated by trans-well invasion assays, and target protein expression was determined by western blotting in LNCaP, DU-145, and PC-3 cells. Luciferase reporter plasmids were constructed to confirm the action of miR-483-5p on downstream target gene RBM5 in HEK-293T cells. Results: we observed that miR-483-5p was upregulated in prostate cancer cell lines and tissues. A miR-483-5p inhibitor inhibited prostate cancer cell growth and invasion in DU-145 and PC-3 cells. miR-483-5p directly bound to the 3' untranslated region (3'UTR) of RBM5 in HEK-293T cells. RBM5 overexpression inhibited prostate cancer cell growth and invasion in LNCaP cells. Enforced RBM5 expression alleviated miR-483-5p promotion of prostate cancer cell growth and invasion in LNCaP cells. Conclusion: The present study describes a potential mechanism underlying a miR-483-5p/RBM5 link that contributes to prostate cancer development.
Descritores: Neoplasias da Próstata/genética
Neoplasias da Próstata/patologia
Regulação Neoplásica da Expressão Gênica/genética
Proteínas de Ciclo Celular/metabolismo
Regiões não Traduzidas/genética
Proteínas Supressoras de Tumor/metabolismo
MicroRNAs/fisiologia
Proliferação de Células/genética
Proteínas de Ligação a DNA/metabolismo
Reação em Cadeia da Polimerase em Tempo Real
-Neoplasias da Próstata/mortalidade
Regulação para Baixo
Regulação para Cima
Proteínas de Ligação a RNA/metabolismo
MicroRNAs/antagonistas & inibidores
Linhagem Celular Tumoral
Invasividade Neoplásica
Limites: Humanos
Masculino
Responsável: BR1.1 - BIREME


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Id: biblio-892856
Autor: Hwang, Eu Chang; Jung, Seung Il; Lee, Hyun-Ju; Lee, Je-Jung; Kwon, Dong Deuk.
Título: Generation of potent cytotoxic T lymphocytes against in male patients with non-muscle invasive bladder cancer by dendritic cells loaded with dying T24 bladder cancer cells
Fonte: Int. braz. j. urol;43(4):615-627, July-Aug. 2017. tab, graf.
Idioma: en.
Resumo: ABSTRACT Background In order to induce a potent cytotoxic T lymphocyte (CTL) response in dendritic cell (DC)-based immunotherapy for bladder cancer, various tumor antigens can be loaded onto DCs. Objective The aim of this study was to establish a method of immunotherapy for male patients with non-muscle invasive bladder cancer (NMIBC), using bladder cancer-specific CTLs generated in vitro by DCs. Materials and Methods Monocyte-derived DCs from bladder cancer patients were induced to mature in a standard cytokine cocktail (IL-1β, TNF-α, IL-6, and PGE2: standard DCs, sDCs) or anα-type 1-polarized DC (αDC1) cocktail (IL-1β, TNF-α, IFN-α, IFN-γ, and polyinosinic:polycytidylic acid) and loaded with the UVB-irradiated bladder cancer cell line, T24. Antigen-loaded αDC1s were evaluated by morphological and functional assays, and the bladder cancer-specific CTL response was analyzed by cytotoxic assay. Results The αDC1s significantly increased the expression of several molecules pertaining to DC maturation, regardless of whether or not the αDC1s were loaded with tumor antigens, relative to sDCs. The αDC1s demonstrated increased production of interleukin-12 both during maturation and after subsequent stimulation with CD40L that was not significantly affected by loading with tumor antigens as compared to that of sDCs. Bladder cancer-specific CTLs targeting autologous bladder cancer cells were successfully induced by αDC1s loaded with dying T24 cells. Conclusion Autologous αDC1s loaded with an allogeneic bladder cancer cell line resulted in increased bladder cancer-specific CTL responses as compared to that with sDCs, and therefore, may provide a novel source of DC-based vaccines that canbe used in immunotherapy for male patients with NMIBC.
Descritores: Neoplasias da Bexiga Urinária/terapia
Células Dendríticas/imunologia
Linfócitos T Citotóxicos/imunologia
Citocinas/uso terapêutico
Imunoterapia/métodos
-Neoplasias da Bexiga Urinária/imunologia
Diferenciação Celular/imunologia
Resultado do Tratamento
Linhagem Celular Tumoral
Imunoterapia/efeitos adversos
Pessoa de Meia-Idade
Limites: Humanos
Masculino
Idoso
Responsável: BR1.1 - BIREME


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Id: biblio-838963
Autor: Kong, Yanping; Zhang, Xianbo; Zhao, Yongliang; Xue, Yanfang; Zhang, Ye.
Título: Uptake of DNA by cancer cells without a transfection reagent
Fonte: Biol. Res;50:2, 2017. graf.
Idioma: en.
Projeto: Hebei province.
Resumo: BACKGROUND: Cancer cells exhibit elevated levels of glucose uptake and may obtain pre-formed, diet-derived fatty acids from the bloodstream to boost their rapid growth; they may also use nucleic acid from their microenvironment. The study of processing nucleic acid by cancer cells will help improve the understanding of the metabolism of cancer. DNA is commonly packaged into a viral or lipid particle to be transferred into cells; this process is called transfection in laboratory. Cancer cells are known for having gene mutations and the evolving ability of endocytosis. Their uptake of DNAs might be different from normal cells; they may take in DNAs directly from the environment. In this report, we studied the uptake of DNAs in cancer cells without a transfection reagent. METHODS: A group of DNA fragments were prepared with PCR and labeled with isotope phosphorous-32 to test their uptake by Huh 7 (liver cancer) and THLE3 (normal liver cells) after incubation overnight by counting radioactivity of the cells' genomic DNA. Multiple cell lines including breast cancer and lung cancer were tested with the same method. DNA molecules were also labeled with fluorescence to test the location in the cells using a kit of "label it fluorescence in situ hybridization (FISH)" from Mirus (USA). RESULTS: The data demonstrated that hepatocellular carcinoma cells possess the ability to take in large DNA fragments directly without a transfection reagent whereas normal liver cells cannot. Huh7 and MDA-MB231 cells displayed a significantly higher Rhodamine density in the cytoplasmic phagosomes and this suggests that the mechanism of uptake of large DNA by cancer cells is likely endocytosis. The efficacy of uptake is related to the DNA's size. Some cell lines of lung cancer and breast cancer also showed similar uptake of DNA. CONCLUSIONS: In the present study, we have revealed the evidence that some cancer cells, but not nontumorigenic cells, can take DNA fragments directly from the environment without the aid of the transfecting reagent.
Descritores: DNA/metabolismo
Transfecção
Neoplasias/genética
-Neoplasias da Mama/genética
Neoplasias da Mama/patologia
alfa-Fetoproteínas/metabolismo
Linhagem Celular
Reação em Cadeia da Polimerase
Hibridização in Situ Fluorescente
Hepatócitos/metabolismo
Genômica
Linhagem Celular Tumoral
Endocitose/genética
Fragmentação do DNA
Lipídeos/farmacologia
Neoplasias Hepáticas/genética
Neoplasias Hepáticas/patologia
Neoplasias Pulmonares/genética
Neoplasias Pulmonares/patologia
Neoplasias/patologia
Limites: Humanos
Feminino
Responsável: CL1.1 - Biblioteca Central


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Id: biblio-838966
Autor: Ramachandran, Gokula Krishnan; Yeow, Chen Hua.
Título: Proton NMR characterization of intact primary and metastatic melanoma cells in 2D & 3D cultures
Fonte: Biol. Res;50:12, 2017. tab, graf.
Idioma: en.
Projeto: MOE Academic research fund.
Resumo: OBJECTIVE: To characterize the differences between the primary and metastatic melanoma cell lines grown in 2D cultures and 3D cultures. METHODS: Primary melanoma cells (WM115) and metastatic melanoma cells (WM266) extracted from a single donor was cultured in 2D as well as 3D cultures. These cells were characterized using proton NMR spectrometry, and the qualitative chemical shifts markers were identified and discussed. RESULTS: In monolayer culture (2D), we observed one qualitative chemical shift marker for primary melanoma cells. In spheroid cultures (3D), we observed nine significant chemical shifts, of which eight markers were specific for primary melanoma spheroids, whereas the other one marker was specific to metastatic melanoma spheroids. This study suggests that the glucose accumulation and phospholipid composition vary significantly between the primary and metastatic cells lines that are obtained from a single donor and also with the cell culturing methods. 14 qualitative chemical shift markers were obtained in the comparison between monolayer culture and spheroids cultures irrespective of the differences in the cell lines. Among which 4 were unique to monolayer cultures whereas 10 chemical shifts were unique to the spheroid cultures. This study also shows that the method of cell culture would drastically affect the phospholipid composition of the cells and also depicts that the cells in spheroid culture closely resembles the cells in vivo. CONCLUSION: This study shows the high specificity of proton NMR spectrometry in characterizing cancer cell lines and also shows the variations in the glucose accumulation and phospholipid composition between the primary and metastatic melanoma cell lines from the same donor. Differences in the cell culture method does plays an important role in phospholipid composition of the cells.
Descritores: Espectroscopia de Ressonância Magnética/métodos
Técnicas de Cultura de Células/métodos
Melanoma/patologia
Melanoma/secundário
-Fosfolipídeos/análise
Fosfolipídeos/metabolismo
Fatores de Tempo
Biomarcadores Tumorais
Análise de Variância
Esferoides Celulares
Linhagem Celular Tumoral
Glucose/análise
Glucose/metabolismo
Melanoma/metabolismo
Limites: Humanos
Responsável: CL1.1 - Biblioteca Central



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