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Pesquisa : A11.872.650 [Categoria DeCS]
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Czeczko, Nicolau Gregori
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Id: biblio-1152637
Autor: Czeczko, Leticia Elizabeth Augustin; Ribas, Carmen Australia Paredes Marcondes; Czeczko, Nicolau Gregori; Skare, Thelma Larocca; Yamakawa, Camila Kienen; Gionedis, Guilherme; Vasconcelos, Cecilia; Bremer, Fabiola Pabst; Castoldi, Diogo Francesco; Gasser, Martin; Waaga-Gasser, Ana Maria.
Título: Are stem cell marker expression and cd133 analysis relevant to differentiate colorectal cancer? / A expressão de marcadores de células-tronco e a análise do cd133 são relevantes na diferenciação do câncer colorretal?
Fonte: ABCD arq. bras. cir. dig;33(4):e1568, 2020. tab, graf.
Idioma: en.
Projeto: Coordenação de Aperfeiçoamento de Pessoal de Nível Superior.
Resumo: ABSTRACT Background: CD133 and AXL have been described as cancer stem cell markers, and c-MYC as a key regulatory cellular mechanism in colorectal cancer (CRC). Aim: Evaluate the prognostic role of the biomarkers CD133, AXL and c-MYC and their association with clinicopathologic characteristics in colorectal adenocarcinomas and adenomas. Methods: A total of 156 patients with UICC stage I-IV adenocarcinomas (n=122) and adenomas (n=34) were analyzed. Tissue microarrays (TMA) from primary tumors and polyps for CD133, c-MYC and AXL expression were performed and analyzed for their significance with clinicopathologic characteristics. Results: Poorly differentiated adenocarcinomas and disease progression were independent risk factors for poor overall survival. The median overall survival time was 30 months. Positive CD133 expression (35.9% of all cases), particularly of right-sided CRCs (44.8% of the CD133+ cases), was negatively correlated with death in the univariate analysis, which did not reach significance in the multivariate analysis. c-MYC (15.4% of all cases) was predominantly expressed in advanced-stage patients with distant (non-pulmonary/non-hepatic) metastasis. AXL expression was found only occasionally, and predominantly dominated in adenomas, with less penetrance in high-grade dysplasia. Conclusions: CD133 expression was not associated with inferior overall survival in CRC. While AXL showed inconclusive results, c-MYC expression in primary CRCs was associated with distant metastasis.

RESUMO Racional: CD133 e AXL são descritos na literatura como marcadores de células-tronco tumorais, e c-MYC cumpre papel chave como mecanismo de regulação celular no câncer colorretal (CCR). Objetivo: Avaliar o papel prognóstico dos biomarcadores CD133, AXL e c-MYC e sua associação com características clinicopatológicas de adenocarcinomas e adenomas colorretais. Métodos: Um total de 156 pacientes com adenocarcinomas de estádio UICC I-IV (n=122) e adenomas (n=34) colorretais foram avaliados. Microarranjos teciduais (TMA) dos tumores primários e adenomas foram realizados em busca de expressão de CD133, c-MYC e AXL, com posterior análise de relação significativa com características clinicopatológicas. Resultados: Adenocarcinomas pobremente diferenciados e progressão de doença foram fatores de risco independentes para má sobrevida global. A taxa mediana de sobrevida global foi de 30 meses. Expressão positiva de CD133 (35,9% dos casos), particularmente em cânceres de cólon direito (44,8% dos casos CD133+), correlacionou-se negativamente com óbito na análise univariada, sem significância estatística na análise multivariada. c-MYC (15,4% dos casos) teve predomínio de expressão em pacientes com estádio avançado com metástases distantes (não-pulmonares/não-hepáticas). Expressão de AXL foi pouco encontrada, com predomínio em adenomas, com menor penetrância em displasia de alto grau. Conclusão: Expressão de CD133 não se associou com sobrevida global inferior em CCR. Enquanto AXL demonstrou resultados inconclusivos, expressão de c-MYC em tumores primários se associou-se à metástases à distância.
Descritores: Neoplasias Colorretais/diagnóstico
Neoplasias Colorretais/patologia
Biomarcadores Tumorais/análise
Antígeno AC133/análise
-Prognóstico
Células-Tronco Neoplásicas/metabolismo
Proteínas Proto-Oncogênicas c-myc/metabolismo
Metástase Neoplásica
Limites: Humanos
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-950762
Autor: Fulawka, Lukasz; Donizy, Piotr; Halon, Agnieszka.
Título: Cancer stem cells - the current status of an old concept: literature review and clinical approaches
Fonte: Biol. Res;47:1-9, 2014. ilus.
Idioma: en.
Resumo: As regards their morphology and biology, tumours consist of heterogeneous cell populations. The cancer stem cell (CSC) hypothesis assumes that a tumour is hierarchically organized and not all of the cells are equally capable of generating descendants, similarly to normal tissue. The only cells being able to self-renew and produce a heterogeneous tumour cell population are cancer stem cells. CSCs probably derive from normal stem cells, although progenitor cells may be taken into consideration as the source of cancer stem cells. CSCs reside in the niche defined as the microenvironment formed by stromal cells, vasculature and extracellular matrix. The CSC assays include FACS sorting, xenotransplantation to immunodeficient mice (SCID), incubation with Hoechst 33342 dye, cell culture in non-adherent conditions, cell culture with bromodeoxyuridine. CSCs have certain properties that make them resistant to anticancer therapy, which suggests they may be the target for potential therapeutic strategies.
Descritores: Células-Tronco Neoplásicas/patologia
Diferenciação Celular/fisiologia
Resistencia a Medicamentos Antineoplásicos/fisiologia
Microambiente Tumoral/fisiologia
Carcinogênese/patologia
Autorrenovação Celular/fisiologia
-Prognóstico
Biomarcadores Tumorais/uso terapêutico
Camundongos SCID
Células Estromais/patologia
Matriz Extracelular/patologia
Microvasos/fisiopatologia
Evolução Clonal/fisiologia
Citometria de Fluxo
Corantes Fluorescentes
Limites: Animais
Camundongos
Tipo de Publ: Revisão
Responsável: CL1.1 - Biblioteca Central


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Id: biblio-1179853
Autor: Mambelli, Lisley Inata.
Título: Estabelecimento e caracterização de células tumorais de pacientes portadores da síndrome de Li-Fraumeni / Establishment and characterization of cancer cells from patients with Li-Fraumeni syndrome.
Fonte: São Paulo; s.n; 2015. 130 p. ilust, tabelas, quadros.
Idioma: pt; fr.
Tese: Apresentada a Fundação Antônio Prudente para obtenção do grau de Doutor.
Resumo: A Síndrome de Li-Fraumeni (LFS) é uma síndrome rara de predisposição hereditária ao câncer relacionada a mutações germinativas no gene TP53. Portadores de mutações neste gene apresentam alto risco para o desenvolvimento de um amplo espectro tumoral em idade precoce. No sul do Brasil, 0,3% da população local é portadora de uma mutação germinativa no códon 337 do gene TP53 (p.R337H) que foi descrita como tendo um efeito fundador no país. Sabe-se que a proteína p53 desempenha um papel crítico na regulação da diferenciação e do padrão de divisão das células tronco (CT). As CT são células capazes de se autorrenovarem e de se diferenciarem em diversos tipos celulares. Estas células têm sido apontadas como responsáveis pela iniciação e progressão tumoral, sendo resistentes aos tratamentos quimioterápicos. Levantou-se a hipótese de que pacientes LFS possuem alto risco para o desenvolvimento de tumores malignos devido a presença de CT em tecidos específicos. O objetivo do presente trabalho foi isolar e caracterizar células tronco tumorais (CTT) de pacientes LFS portadores de mutações germinativas no gene TP53. As amostras tumorais foram obtidas mediante consentimento informado e no total, 12 culturas de células primárias de 11 pacientes LFS com e sem a mutação p.R337H foram estabelecidas. Uma cultura de células oriunda de um carcinoma de mama foi o enfoque do presente estudo. O novo protocolo nomeado "ALTERNADO" (cultura em monocamada ­ cultura em suspensão (mamoesferas) ­ cultura em monocamada) foi elaborado e permitiu o cultivo prolongado das células obtidas sem sinais de senescência. Os métodos de imunofluorescência e citometria de fluxo demonstraram que estas células apresentam o mesmo perfil imunofenotípico CD44high/+, CD24low/- e ALDH+ previamente descrito para CTT de mama. Ainda, observamos a expressão dos seguintes marcadores: nanog, sox2, oct3/4, p53 e Ki67. A videomicroscopia por time-lapse permitiu a observação de divisões simétricas frequentes e ausência de fenótipos senescentes na cultura obtida. A análise do padrão de divisão celular utilizando o anti-oct3/4 demonstrou que ambos os tipos de divisões (simétrica e assimétrica) ocorrem, porém a divisão simétrica se mostrou mais frequente. Além disso, as células apresentaram capacidade de diferenciação in vitro para as linhagens adipogênica e osteogênica, bem como alta capacidade clonogênica. O perfil da expressão dos receptores de estrógeno e progesterona, além da capacidade proliferativa demonstrada pelo anti-Ki67 se mostrou idêntica ao observado no anatomopatológico do tumor, porém, diferentemente do tumor, algumas células tiveram marcação citoplasmática para o receptor HER2. A análise de expressão gênica em larga escala revelou perfil diferencial de expressão entre as mamoesferas e as células aderentes, sendo que os principais genes diferencialmente expressos na mamoesfera estavam relacionados com o aumento da capacidade de metástase e invasão. Por meio do ensaio de invasão demonstramos que as mamoesferas possuem células com maior capacidade de invasão quando comparadas as mesmas células cultivadas em monocamada. Estabelecemos, pela primeira vez, um banco de células a partir de diferentes tipos tumorais de pacientes LFS. As culturas celulares primárias estabelecidas e os dados apresentados no presente trabalho são de extrema importância para o melhor entendimento do papel desta mutação específica e também do gene TP53 na biologia dos tumores desta coorte de pacientes

Li-Fraumeni Syndrome (LFS) is a rare syndrome of hereditary predisposition to cancer which is related to germline mutations in TP53 gene. Carriers of mutations in this gene are at high risk for the development of a broad spectrum of tumors in early ages. In southern Brazil, 0,3% of the local population is carrier of a germline mutation in codon 337 of TP53 gene (p.R337H) which was described as having a founder effect in the country. It is known that p53 plays a critical role in the regulation of differentiation and the pattern of stem cells (SC) division. SC are cells capable of self renewing and differentiating to different cell types. These cells have been identified as responsible for tumor initiation and progression, being resistant to chemotherapy treatments. It was hypothesized that LFS patients are at high risk for developing malignant tumors due to the presence of SC in specific tissues. The objective of the present study was to isolate and characterize tumor stem cells (CSC) of LFS patients carriers of germline mutations in TP53 gene. Tumor samples were obtained with informed consent and in total, 12 primary cultures from 11 patients with and without LFS p.R337H mutation were established. A culture of cells derived from a breast carcinoma was the focus of the present study. The new protocol named "ALTERNATE" (monolayer culture - suspension culture (mammospheres) - monolayer culture) was prepared and allowed extended cultivation of obtained cells without signs of senescence. Immunofluorescence and flow cytometry assays demonstrated that these cells shared the same immunophenotypic profile CD44high/+, CD24low/- and ALDH+ previously described for breast CSC. We also observed the expression of the following markers: nanog, sox2, oct3/4, p53 and ki67. The videomicroscopy by time-lapse allowed the observation of frequent symmetric divisions and the lack of senescent phenotypes in established culture. The cell division pattern analysis by using anti-oct3/4 showed that both types of divisions (symmetric and asymmetric) occur, but symmetric division was more frequently observed. Moreover, the cells had the ability to differentiate in vitro to osteogenic and adipogenic lineages, as well as possess high clonogenic capacity. The expression profile of estrogen and progesterone receptors, as well as proliferative capacity demonstrated by anti-ki67 showed identical pattern to that observed in the tumor, however, some cells began to express HER2 receptor in cytoplasm. The microarray analysis revealed distinct gene expression profile between mammospheres and adherent cells, while the major differentially expressed genes in mammospheres were associated with increased metastasis and invasion ability. Through the invasion assay we demonstrated that our cells cultured as mammospheres possess high invasive capacity when compared to the same population of cells but which were cultured in monolayer. Herein, we established for the first time a bank of cells from different tumor types of LFS patients. These obtained cell cultures and the results presented in this study are extremely important to better understand the role of this specific mutation and also the TP53 gene in tumor biology of this cohort of patients
Descritores: Células-Tronco Neoplásicas
Genes p53
Imunofluorescência
Síndrome de Li-Fraumeni
Citometria de Fluxo
Limites: Humanos
Masculino
Feminino
Adulto
Pessoa de Meia-Idade
Idoso
Responsável: BR30.1 - Biblioteca
BR30.1


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Id: biblio-1136233
Autor: Zhu, Xi-De; Gao, Zhen-Juan; Zheng, Guo-Dong.
Título: miR-125a-5p inhibits cancer stem cells phenotype and epithelial to mesenchymal transition in glioblastoma
Fonte: Rev Assoc Med Bras (1992);66(4):445-451, 2020. graf.
Idioma: en.
Resumo: SUMMARY OBJECTIVE Glioblastoma (GBM) is a common type of cancer with high mortality. Epithelial to mesenchymal transition (EMT) plays a vital role in the development of glioblastoma. The aim of this study is to evaluate the role of miR-125a-5p in glioblastoma and in the tumorigenesis of chemotherapeutic drug-resistant cancer stem-like cells in brain glioma. METHODS The role of miR-125a-5p in the regulation of CSCs, EMT, migration, and invasion in glioblastoma was measured in this study. RESULTS We showed the roles of miR-125a-5p in the regulation of CSCs, EMT, migration, and invasion in glioblastoma. miR-125a-5p can inhibit the CSCs phenotype and EMT in glioblastoma cells. In addition, its over-expression can significantly regulate CSCs-associated genes and EMT-associated gene expression in glioblastoma cells. CONCLUSIONS We concluded that miR-125a-5p is one of the key microRNAs regulating CSCs and EMT programs in glioblastoma. The results suggested that miR-125a-5p might be a novel therapy target for glioblastoma.

RESUMO OBJETIVO O glioblastoma (GBM) é um câncer comum e de alta mortalidade. A transição epitélio-mesênquima (EMT) desempenha um papel vital no desenvolvimento do glioblastoma. O objetivo deste estudo é avaliar o papel do miR-125a-5p no glioblastoma e a tumorigênese de células-troco cancerígenas resistentes a medicamentos quimioterápicos em gliomas cerebrais. METODOLOGIA Os papéis do miR-125a-5p na regulação de células-tronco cancerígenas, EMT, migração e invasão do glioblastoma foram medidos neste estudo. RESULTADOS Mostramos a função do miR-125a-5p na regulação das células-tronco cancerígenas, EMT, migração e invasão do glioblastoma. O miR-125a-5p pode inibir o fenótipo e a EMT de células-tronco cancerígenas em células de glioblastoma. Além disso, a sua superexpressão pode regular de forma significante genes associados às células-tronco cancerígenas e a expressão de genes associados à EMT em células de glioblastoma. CONCLUSÕES Concluímos que o miR-125a-5p é um dos principais microRNAs na regulação de células-tronco cancerígenas e programas de EMT em glioblastomas, e os resultados sugerem que o miR-125a-5p pode ser um novo alvo terapêutico em casos de glioblastoma.
Descritores: Glioblastoma
MicroRNAs
-Fenótipo
Células-Tronco Neoplásicas
Regulação Neoplásica da Expressão Gênica
Movimento Celular
Linhagem Celular Tumoral
Proliferação de Células
Transição Epitelial-Mesenquimal
Limites: Humanos
Responsável: BR1.1 - BIREME


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Id: biblio-1136246
Autor: Sha, Yeqin; Lei, Daoyun; He, Lianping.
Título: Manipulating miR-125a-5p to regulate cancer stem cells phenotype and epithelial to mesenchymal transition in glioblastoma
Fonte: Rev Assoc Med Bras (1992);66(5):706-706, 2020.
Idioma: en.
Descritores: Células-Tronco Neoplásicas/patologia
Glioblastoma/patologia
MicroRNAs/genética
MicroRNAs/metabolismo
Transição Epitelial-Mesenquimal/genética
-Fenótipo
RNA Mensageiro/genética
RNA Mensageiro/metabolismo
Regulação Neoplásica da Expressão Gênica
Glioblastoma/genética
Proliferação de Células
Genes Neoplásicos
Limites: Humanos
Responsável: BR1.1 - BIREME


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Id: biblio-887236
Autor: Bautista, Wendy; Lipschitz, Jeremy; McKay, Andrew; Minuk, Gerald Y.
Título: Cancer Stem Cells are Depolarized Relative to Normal Stem Cells Derived from Human Livers
Fonte: Ann. hepatol;16(2):297-303, Mar.-Apr. 2017. tab, graf.
Idioma: en.
Resumo: ABSTRACT Introduction and aim. The inability to distinguish cancer (CSCs) from normal stem cells (NSCs) has hindered attempts to identify safer, more effective therapies for hepatocellular carcinoma (HCC). The aim of this study was to document and compare cell membrane potential differences (PDs) of CSCs and NSCs derived from human HCC and healthy livers respectively and determine whether altered GABAergic innervation could explain the differences. Material and methods. Epithelial cell adhesion molecule (EpCAM) positive stem cells were isolated from human liver tissues by magnetic bead separations. Cellular PDs were recorded by microelectrode impalement of freshly isolated cells. GABAA receptor subunit expression was documented by reverse transcriptase polymerase chain reaction (RT-PCR) and immunofluorescence. Results. CSCs were significantly depolarized (-7.0 ± 1.3 mV) relative to NSCs (-23.0 ± 1.4 mV, p < 0.01). The depolarized state was associated with different GABAA receptor subunit expression profiles wherein phasic transmission, represented by GAGAA α3 subunit expression, was prevalent in CSCs while tonic transmission, represented by GABAA α6 subunit expression, prevailed in NSCs. In addition, GABAA subunits α3, β3, γ3 and δ were strongly expressed in CSCs while GABAA π expression was dominant in NSCs. CSCs and NSCs responded similarly to GABAA receptor agonists (ΔPD: 12.5 ± 1.2 mV and 11.0 ± 3.5 mV respectively). Conclusion. The results of this study indicate that CSCs are significantly depolarized relative to NSCs and these differences are associated with differences in GABAA receptor subunit expression. Together they provide new insights into the pathogenesis and possible treatment of human HCC.
Descritores: Células-Tronco Neoplásicas/metabolismo
Receptores de GABA-A/metabolismo
Carcinoma Hepatocelular/genética
Carcinoma Hepatocelular/metabolismo
Agonistas de Receptores de GABA-A/farmacologia
Molécula de Adesão da Célula Epitelial/metabolismo
Fígado/citologia
Neoplasias Hepáticas/metabolismo
-Fenótipo
Células-Tronco/efeitos dos fármacos
Células-Tronco Neoplásicas/efeitos dos fármacos
RNA Mensageiro/genética
RNA Mensageiro/metabolismo
Biomarcadores/metabolismo
Imunofluorescência
Separação Imunomagnética
Receptores de GABA-A/efeitos dos fármacos
Receptores de GABA-A/genética
Reação em Cadeia da Polimerase Via Transcriptase Reversa
Subunidades Proteicas
Neoplasias Hepáticas/genética
Potenciais da Membrana/efeitos dos fármacos
Limites: Humanos
Responsável: BR1.1 - BIREME


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Id: biblio-954187
Autor: Riesco-Vásquez, Fernando; Rojas-Morán, Nancy; Enciso-Benavides, Nathaly; Cisneros-Huamaní, Carlos; Tejero-Ortego, Concepción; Alfaro-Quillas, Luis; Enciso-Gutiérrez, Javier.
Título: Ultraestructura del inmunofenotipo CD44+/CD24- de una línea de células de cáncer de mama triple negativo / Ultrastructure of the CD44 + / CD24- immunophenotype of a line of triple negative breast cancer cells
Fonte: Int. j. morphol;36(3):792-798, Sept. 2018. tab, graf.
Idioma: es.
Projeto: INNOVATE PERÚ.
Resumo: RESUMEN: El cáncer de mama es la principal causa de muerte debido al cáncer en mujeres. La microscopía electrónica permite establecer características constitutivas de las células entre diferentes poblaciones celulares. Las células madre del cáncer mamario con inmunofenotipo CD44alta/CD24baja son una población de células intratumorales asociada a la quimioresistencia y metástasis, cuya ultraestructura aún no ha sido bien estudiada. El objetivo de este trabajo fue conocer características ultraestructurales de células con fenotipo de células madre del cáncer de la línea celular MDA-MB-436 de tumor mamario triple negativo comparándolas con células madre adiposas. Se utilizó microscopía electrónica de barrido y de transmisión. Previamente, mediante separación inmunomagnética positiva empleando anticuerpos anti CD44 y anti CD24 unidos a perlas magnéticas, se obtuvo una población de células con fenotipo CD44alta/CD24baja a partir de 10x106 células de la línea MDA-MB-436, la cual igual que las células madre adiposas fue cultivada en cubreobjetos para microscopía electrónica de barrido; en tanto que para microscopía electrónica de transmisión se obtuvo un pellet de células, luego se fijó con glutaraldehído al 2,5 % y post fijó con OsO4 1 %. Para microscopía óptica de alta resolución se usó azul de toluidina como tinción. Luego de obtener el fenotipo de células madre del cáncer se corroboró su pluripotencia detectando la expresión de los genes Oct4 y nanog mediante RT-PCR. Nuestros resultados muestran que las células de este fenotipo son pequeñas, redondeadas, recubiertas por microvellosidades abundantes pero cortas; el citoplasma tiene organelas de secreción celular y abundantes mitocondrias alargadas; el núcleo es excéntrico ocupando la mitad del volumen celular, el nucléolo es voluminoso y la heterocromatina está adosada a la membrana nuclear interna. Se concluye que el inmunofenotipo celular estudiado es una sub población celular dentro de la línea estudiada que difiere en tamaño y ultraestructura de las células madre adiposas.

SUMMARY: Breast cancer is the leading cause of cancer deaths in women. Electron microscopy allows establishing constitutive characteristics of cells between different cell populations. CD44 high / CD24 low mammary cancer stem cells are a population of intratumoral cells associated with chemoresistance and metastasis, whose ultrastructure has not yet been well studied. The objective of this work was to know the ultrastructural characteristics of cells with cancer stem cell phenotype, of the triple negative mammary tumor cell line MDAMB-436 436 using scanning and transmission electron microscopy, and to contrast them with adipose-derived mesenchymal stem cells. Previously, by immunomagnetic purification using anti CD44 and anti CD24 antibodies bound to magnetic beads, cells populations was obtained from 10x106 cells of the MDA-MB-436 line, which, adipose-derived mesenchymal stem whereas cultivated on coverslips for scanning electron microscopy; while for transmission electron microscopy a cell pellet was obtained, then fixed with 2.5 % glutaraldehyde and post fixed with OsO4 1 %. For high resolution optical microscopy, toluidine blue was used as staining. After obtaining the phenotype of cancer stem cells, their pluripotency was corroborated by detecting the expression of the Oct4 and nanog genes by RT-PCR. Our results show that the cells of this phenotype are small, rounded, covered by abundant but short microvilli; the cytoplasm has organelles of cellular secretion and abundant elongated mitochondria; the nucleus is eccentric occupying half of the cellular volume, the nucleolus is bulky and the heterochromatin is attached to the inner nuclear membrane. It is concluded that the cellular immunophenotype studied is a sub-cellular population within the line studied that differs in size and ultrastructure of the adipose stem cells.
Descritores: Células-Tronco Neoplásicas/ultraestrutura
Neoplasias da Mama/patologia
-Microscopia Eletrônica
Imunofenotipagem
Linhagem Celular Tumoral/ultraestrutura
Reação em Cadeia da Polimerase em Tempo Real
Limites: Humanos
Feminino
Responsável: CL1.1 - Biblioteca Central


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Id: biblio-893672
Autor: Rodini, Camila Oliveira; Lopes, Nathália Martins; Lara, Vanessa Soares; Mackenzie, Ian Campbell.
Título: Oral cancer stem cells - properties and consequences
Fonte: J. appl. oral sci;25(6):708-715, Nov.-Dec. 2017. graf.
Idioma: en.
Projeto: FAPESP (São Paulo Research Foundation).
Resumo: Abstract Research on cancer stem cells (CSCs) has greatly increased in the field of medicine and pathology; however, some conceptual misunderstandings are still present among the public as well as within the general scientific community that is not yet familiar with the subject. The very first problem is the misinterpretation of CSCs as a synonym of their normal counterparts, the well-known stem cells (SCs). Particularly in Dentistry, another common mistake is the misinterpretation of oral CSCs as normal tooth-derived SCs. The present review aims to clarify important concepts related to normal SCs and CSCs, as well as discuss the relevance of CSCs to the development, metastasis and therapy resistance of oral squamous cell carcinoma.
Descritores: Células-Tronco Neoplásicas/patologia
Neoplasias Bucais/patologia
Carcinoma de Células Escamosas/patologia
-Diferenciação Celular
Transformação Celular Neoplásica
Transição Epitelial-Mesenquimal
Limites: Humanos
Tipo de Publ: Revisão
Responsável: BR1.1 - BIREME


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Id: biblio-888984
Autor: Wanandi, SI; Yustisia, I; Neolaka, GMG; Jusman, SWA.
Título: Impact of extracellular alkalinization on the survival of human CD24-/CD44+ breast cancer stem cells associated with cellular metabolic shifts
Fonte: Braz. j. med. biol. res = Rev. bras. pesqui. méd. biol;50(8):e6538, 2017. tab, graf.
Idioma: en.
Resumo: Cancer stem cells reside in a distinct region within the tumor microenvironment that it is believed to play a fundamental role in regulating stemness, proliferation, survival, and metabolism of cancer cells. This study aimed to analyze the effect of extracellular alkalinization on metabolism and survival of human CD24-/CD44+ breast cancer stem cells (BCSCs). BCSCs were cultured in alkalinized DMEM-F12 and incubated at 37°C, 5% CO2, and 20% O2 for 30 min, 6, 24, and 48 h. After each incubation period, we analyzed the modulation of various mRNA expressions related to pH and cellular metabolic regulation using the qRT-PCR. Metabolic state was measured using colorimetric and fluorometric assays. To examine cell proliferation and apoptosis, we used trypan blue and annexin V/propidium iodide assay, respectively. This study demonstrated that alkalinization could stimulate extracellular carbonic anhydrase (CAe) activity, as well as CA9 and HIF1α expression. Under alkaline pH and HIF1α regulation, glucose consumption, extracellular lactate production, and LDH activity of BCSCs were upregulated while O2 consumption was downregulated. These metabolic shifts seemed to promote apoptosis and suppress the proliferation of BCSCs. To conclude, modulation of the extracellular environment through alkalinization could change the metabolic states of BCSCs, which in turn affect the cell survival.
Descritores: Neoplasias da Mama/metabolismo
Antígeno CD24/metabolismo
Receptores de Hialuronatos/metabolismo
Células-Tronco Neoplásicas/metabolismo
-Apoptose
Proliferação de Células
Sobrevivência Celular
Espaço Extracelular
Regulação Neoplásica da Expressão Gênica
Reação em Cadeia da Polimerase Via Transcriptase Reversa
Limites: Humanos
Feminino
Responsável: BR1.1 - BIREME



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