Name: lung tumor cell recruitment assay
Uploaded: 2019-02-26T12:30:00
Description: Watch this Scientific Journal Video about Lung Tumor Cell Recruitment Assay at JoVE.com

Todos os procedimentos realizados com ratos foram aprovados pela Universidade de medicina Animal pesquisa Comitê de Tóquio feminino.
1. cauda veia injeção de células de Carcinoma (LLC) pulmão de Lewis
<ol><li>Manter as células LLC em DMEM suplementado com 10% de FCS, em um 5% umidificado incubadora de CO2 a 37 ° C. Células devem conter um sistema de expressão de proteína fluorescente (por exemplo, as boas práticas agrícolas).</li>
	<li>Remova células da plac...

<ol>
	<li>Valastyan, S., Weinberg, R. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Tumor+metastasis:+molecular+insights+and+evolving+paradigms.">Tumor metastasis: molecular insights and evolving paradigms.</a> Cell. 147 (2), 275-292 (2011).</li><li>Kaplan, R. N., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=VEGFR1-positive+haematopoietic+bone+marrow+progenitors+initiate+the+pre-metastatic+niche.">VEGFR1-positive haematopoietic bone marrow progenitors initiate the pre-metastatic niche.</a> Nature. 438 (7069), 820-827 (2005).</li><li>Hiratsuka, S., Watanabe, A., Aburatani, H., Maru, Y. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Tumour-mediated+upregulation+of+chemoattractants+and+recruitment+of+myeloid+cells+predetermines+lung+metastasis.">Tumour-mediated upregulation of chemoattractants and recruitment of myeloid cells predetermines lung metastasis.</a> Nature Cell Biology. 8 (12), 1369-1375 (2006).</li><li>Hiratsuka, S., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+S100A8-serum+amyloid+A3-TLR4+paracrine+cascade+establishes+a+pre-metastatic+phase.">The S100A8-serum amyloid A3-TLR4 paracrine cascade establishes a pre-metastatic phase.</a> Nature Cell Biology. 10 (11), 1349-1355 (2008).</li><li>Tomita, T., Sakurai, Y., Ishibashi, S., Maru, Y. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Imbalance+of+Clara+cell-mediated+homeostatic+inflammation+is+involved+in+lung+metastasis.">Imbalance of Clara cell-mediated homeostatic inflammation is involved in lung metastasis.</a> Oncogene. 30 (31), 3429-3439 (2011).</li><li>Deguchi, A., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Serum+amyloid+A3+binds+MD-2+to+activate+p38+and+NF-&#954;B+pathways+in+a+MyD88-dependent+manner.">Serum amyloid A3 binds MD-2 to activate p38 and NF-&#954;B pathways in a MyD88-dependent manner.</a> Journal of Immunology. 191 (4), 1856-1864 (2013).</li><li>Erler, J. T., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Hypoxia-induced+lysyl+oxidase+is+a+critical+mediator+of+bone+marrow+cell+recruitment+to+form+the+premetastatic+niche.">Hypoxia-induced lysyl oxidase is a critical mediator of bone marrow cell recruitment to form the premetastatic niche.</a> Cancer Cell. 15, 35-44 (2009).</li><li>Huang, Y., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Pulmonary+vascular+destabilization+in+the+premetastatic+phase+facilitates+lung+metastasis.">Pulmonary vascular destabilization in the premetastatic phase facilitates lung metastasis.</a> Cancer Research. 69 (19), 7292-7237 (2009).</li><li>Sceneay, J., Smyth, M. J., M&#246;ller, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+pre-metastatic+niche:+finding+common+ground.">The pre-metastatic niche: finding common ground.</a> Cancer Metastasis Reviews. 32 (3-4), 449-464 (2013).</li><li>Castle, J., Shaker, H., Morris, K., Tugwood, J. D., Kirwan, C. C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+significance+of+circulating+tumor+cells+in+breast+cancer:+A+review.">The significance of circulating tumor cells in breast cancer: A review.</a> The Breast. 23, 552-560 (2014).</li><li>Wolf, M. J., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Endothelial+CCR2+signaling+induced+by+colon+carcinoma+cells+enables+extravasation+via+the+JAK2-Stat5+and+p38MAPK+pathway.">Endothelial CCR2 signaling induced by colon carcinoma cells enables extravasation via the JAK2-Stat5 and p38MAPK pathway.</a> Cancer Cell. 22 (1), 91-105 (2012).</li><li>Hiratsuka, S., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Primary+tumours+modulate+innate+immune+signalling+to+create+pre-metastatic+vascular+hyperpermeability+foci.">Primary tumours modulate innate immune signalling to create pre-metastatic vascular hyperpermeability foci.</a> Nature Communications. 4, 1853 (2013).</li><li>Deguchi, A., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Eritoran+inhibits+S100A8-mediated+TLR4/MD-2+activation+and+tumor+growth+by+changing+the+immune+microenvironment.">Eritoran inhibits S100A8-mediated TLR4/MD-2 activation and tumor growth by changing the immune microenvironment.</a> Oncogene. 35 (19), 1445-1456 (2016).</li><li>Ieguchi, K., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=ADAM12-cleaved+ephrin-A1+contributes+to+lung+metastasis.">ADAM12-cleaved ephrin-A1 contributes to lung metastasis.</a> Oncogene. 33 (17), 2179-2190 (2014).</li></ol>

Pré-tratamento de ratos com anticorpos, drogas, uma dieta high-fat ou tumor-condicionado médio antes da injeção de células de tumor é possível. O passo mais difícil neste ensaio é a injeção de veia de cauda. Injeção incompleta resulta em dados inconclusivos. A veia da cauda em C57BL/6 é particularmente difícil de identificar, resultando em falhadas injeções. Colocando o rato sobre uma almofada de aquecimento (37 ° C) ajuda a dilata a veia da cauda para que a injeção se torna mais fácil.
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Metástase de tumor responsável por elevada mortalidade em doenças relacionadas ao câncer. Do ponto de vista das investigações a nível molecular, a metástase pode ser dividido em várias etapas: iniciação do tumor no local do tumor primário, o crescimento do tumor primário e invasão em vizinhas tecidos, intravasation, circulação através dos vasos sanguíneos , extravasamento em órgãos distantes e re-crescimento do tumor. Cada etapa envolve diferentes conjuntos de moléculas/sinais1.
Estudos até à data têm se preocupado com eventos que ocorrem em órgãos distantes, antes que as células do tumor começam circulando no sangue, o que também é conhecido como a fase pre-metastática2,3,4,5, 6. Nossos estudos de modelo de rato revelaram que a fase pré-metastática facilita a metástase do pulmão através da criação de longa duração e baixo nível de respostas inflamatórias nos pulmões. A fase pré-metastática é caracterizada por hyperpermeability de themicrovasculature, recrutamento de células derivada de medula óssea (BMDC) e upregulation das moléculas cytokine/chemokine-like, incluindo S100A8 e SAA33,4 . Tem sido relatado que lisil oxidase modifica a matriz extracelular nos pulmões para recrutar BMDCs7. Outro relatório revelou a importância da Angpt2, MMP3 e MMP10 na fase pre-metastática8. Em outras palavras, as intricadas interações entre tumores primários da medula óssea e órgãos remotos precisam ser entendido e corretamente modulada (por exemplo, usando drogas que proteínas envolvidas nessas interações de destino) para evitar futura metástase9 . Para regular a fase pré-metastática, deve primeiro ser visualizado e avaliado para intervenções de diagnósticos ou terapêuticas. Aqui, nós relatamos um ensaio de recrutamento de células do tumor pulmonar que permite o estudo da fase pré-metastático nos pulmões.
Células tumorais injetadas diretamente dentro do vaso sanguíneo do mouse são semelhantes aos circulam células tumorais em pacientes com câncer, embora possa haver diferenças entre culturas de células e células tumorais de circulação. Circulantes de células de tumor se se submeter a algumas mudanças características quando entram em circulação do tumor primário. No entanto, culturas de células podem formar tumores em camundongos imunodeficientes quando eles são injetados na veia da cauda. Além disso, no sistema modelo de rato, fluorescência rotulada células tumorais pode ser usada que permitem o acompanhamento destas células no corpo. O comportamento de células tumorais em circulação é fundamental ao determinar as consequências finais em pacientes de câncer10. Sangue não é um bom lugar para a sobrevivência de células de tumor2. Eles precisam escapar do ataque, o sistema imunológico do hospedeiro e precisar de anti-apoptotic sinais para prevenir apoptose devido a falta de suporte físico. Células tumorais com habilidades superiores de iniciação de tumor metastático locais geram mais nódulos de tumor. Se as células do tumor mostram tropismo de órgão específico, metástase deve ser observada nesses órgãos particulares. Neste ensaio, os passos iniciais da cascata metastática (invasão e crescimento do tumor primário) não estão incluídos e, portanto o foco na interação entre circulantes de células tumorais e as células do estroma (células endoteliais, células epiteliais e células do sangue). Em ensaios de injeção convencional tumor celular, pesquisadores precisa esperar até nódulos de tumor crescem para um tamanho de tangível para detectar metástase. Neste caso, não é possível quantificar o número exato de células tumorais no vaso sanguíneo. Além disso, este processo inclui uma fase de rebrota de tumor, indicando que outros fatores nas células de tumor podem afetar o resultado.
Contando rotulado células tumorais sob um microscópio de fluorescência é um processo simples. O microscópio estereoscópico fornece um amplo campo de visão, para que o pulmão inteiro pode ser digitalizado. Citometria de fluxo é também uma ferramenta útil que instantaneamente dá um número exato de células tumorais no tecido. Contar as células fluorescentes no tecido com um microscópio confocal é igualmente possível e exibe as imagens mais precisas das células do tumor metastático, mas é demorado e pode dar resultados tendenciosos se apenas uma área selecionada é contabilizada. O objetivo deste teste é observar como facilmente as células do tumor se acumular nos pulmões. Como relatado anteriormente3,4, se os pulmões estão em fase pré-metastático devido a sinalização inflamatória do tumor primário, as células do tumor injetado são propensas a se acumular nos pulmões, implicando, portanto, maiores chances de metástase pulmonar. Outras doenças (artrite reumatoide, asma, etc.) e o seu tratamento com agentes anti-inflamatórios (como o anti-TNFa) podem atenuar metástase pulmonar. Assim, podemos concluir que este ensaio é uma ferramenta poderosa para avaliar a possibilidade de metástase pulmonar.

<table border="1" fo:keep-together.within-page="1" fo:keep-with-next.within-page="always">
	<tbody>
		<tr>
			<td>Collagenase</td>
			<td>Sigma</td>
			<td>C6885</td>
			<td></td>
		</tr>
		<tr>
			<td>Dispase</td>
			<td>Gibco</td>
			<td>17105-041</td>
			<td></td>
		</tr>
		<tr>
			<td>Bovine serum albumin</td>
			<td>Sigma</td>
			<td>A7030</td>
			<td></td>
		</tr>
		<tr>
			<td>DPBS</td>
			<td>Gibco</td>
			<td>14190-144</td>
			<td>no calcium, no magnesium</td>
		</tr>
		<tr>
			<td>Deoxyribonuclease I</td>
			<td>Sigma</td>
			<td>DN-25</td>
			<td>trace amount</td>
		</tr>
		<tr>
			<td>RBC lysis buffer</td>
			<td>Sigma</td>
			<td>R7757</td>
			<td></td>
		</tr>
		<tr>
			<td>Cell strainer</td>
			<td>BD</td>
			<td>352340</td>
			<td>40 micrometer mesh</td>
		</tr>
		<tr>
			<td>Fluorescence labeling kit</td>
			<td>Sigma</td>
			<td>MIN26-KIT</td>
			<td></td>
		</tr>
		<tr>
			<td>DMEM</td>
			<td>Gibco</td>
			<td>11965-092</td>
			<td></td>
		</tr>
		<tr>
			<td>0.22 &#956;m syringe filter</td>
			<td>sartorius</td>
			<td>17597K</td>
			<td></td>
		</tr>
		<tr>
			<td>O.C.T. compound</td>
			<td>Sakura Finetek</td>
			<td>4583</td>
			<td></td>
		</tr>
		<tr>
			<td>4% Paraformaldehyde Phosphate Buffer Solution</td>
			<td>Wako</td>
			<td>163-20145</td>
			<td></td>
		</tr>
	</tbody>
</table>

lung tumor cell recruitment assay

Para investigar os mecanismos moleculares que regem a metástase do tumor, foram propostos vários ensaios usando o mouse como um animal de modelo. Aqui, demonstramos um ensaio simples para avaliar o extravasamento de células de tumor ou micrometastasis. Neste ensaio, células tumorais foram injetadas na veia da cauda, e após um curto período, os pulmões foram dissecados e digeridos para contar as células de tumor rotulado acumulada. Este ensaio ignora o passo inicial da invasão do tumor primário para os vasos sanguíneos e facilita o estudo dos acontecimentos no órgão distante, onde ocorre a metástase do tumor. O número de células injetadas dentro do vaso sanguíneo pode ser otimizado para observar um número limitado de metástases. Relatou-se que as células do estroma no órgão distante contribuem para metástase. Assim, este ensaio poderia ser uma ferramenta útil para explorar o potenciais terapêuticas drogas ou dispositivos para prevenção de metástases de tumor.

Os pulmões apresentam muitas células GFP-LLC 2 h após a injeção (figura 1A). Note-se que as manchas fluorescentes também detectadas no filtro vermelho devem ser excluídas a contagem do número de células. A grande maioria das células LLC desaparece dos pulmões 24 h após a injeção (Figura 1).
Para confirmar o número do GFP-LLC nos pulmões, um dos lóbulos ...

Watch this Scientific Journal Video about Lung Tumor Cell Recruitment Assay at JoVE.com

Lung Tumor Cell Recruitment Assay

Ensaio de recrutamento de células de Tumor de pulmão

Este manuscrito descreve um método para quantificar o acúmulo de células de tumor nos pulmões em um modelo animal de metástases de tumor.

To investigate the molecular mechanisms governing tumor metastasis, various assays using the mouse as a model animal have been proposed. Here, we ...

Este método pode ajudar a responder perguntas-chave no campo da biologia tumoral sobre os mecanismos moleculares da metástase. A principal vantagem dessa técnica é que o recrutamento de células tumorais dentro de um órgão remoto pode ser quantitado. Comece usando um reagente de dissociação celular não enzimática para remover o carcinoma pulmonar de Lewis, ou LLC, de acordo com os protocolos padrão.Transfira a solução celular resultante para um tubo cônico de 15 mililitros antes da centrifugação, e a centrífuga lave as pelotas duas vezes em cinco mililitros de PBS por lavagem. Após a segunda lavagem, filtre as células através de um coador de células poros de 40 micrômetros e dilua a suspensão para uma única vezes 10 para as seis células por concentração mililitro. Em seguida, carregue as células em uma seringa de um mililitro equipada com uma agulha calibre 29, e injete 100 microliters de células na veia traseira de cada 8 a 10 semanas de idade, C57-Black-6, rato masculino.No ponto final experimental apropriado, use uma tesoura para remover a pele da superfície ventral de cada rato, e corte as costelas e o diafragma para expor a cavidade torácica. Use uma agulha de infusão e tubos alados de calibre 25 para lavar 15 mililitros de PBS através do ventrículo direito, e remover o coração e o timo. Agarrando a traqueia com fórceps, puxe para cima, dissecando os tecidos conjuntivos ao redor da traqueia, para colher os pulmões.Em seguida, lave os pulmões em PBS, e desprende um lobo para visualização das células fluorescentes in situ sob um microscópio de fluorescência. Para digerir o tecido pulmonar, primeiro pique o lobo caudal com uma tesoura, e coloque os pedaços de pulmão em uma seringa de 10 mililitros. Feche a seringa com o êmbolo, e aspire cinco mililitros de solução de digestão na seringa, movendo o êmbolo para dentro e para fora do eixo da seringa até que o tecido pulmonar seja disseminado em toda a solução.Distribua o chorume pulmonar em um tubo de 50 mililitros, e digerir o tecido em um agitador recíproco por 15 minutos a 37 graus Celsius e 150 rpm. No final da incubação, triturar o tecido restante até que as células pulmonares estejam completamente dispersas, e devolva o tubo ao agitador por mais 30 minutos. Em seguida, filtrar as células através de um filtro de poros de 40 micrômetros, e coletar as células por centrifugação.Para analisar as células pulmonares isoladas por citometria de fluxo, resuspensar a pelota em dois mililitros de tampão de lise de glóbulos vermelhos por um minuto à temperatura ambiente, e coletar as células por centrifugação. Em seguida, centrifugar a pelota duas vezes em cinco mililitros de PBS fresco suplementado com 1% de gêrio bovino por lavagem. Após a segunda centrifugação, resuspenque a pelota em um mililitro de PBS fresco mais BSA, e filtre as células através de um novo filtro de poros de 40 micrômetros para quantificação das células tumorais por citometria de fluxo.Os pulmões apresentam muitas células GFP-LLC duas horas após a injeção, com a grande maioria das células desaparecendo dos pulmões dentro de 24 horas. Observe que quaisquer manchas fluorescentes detectadas dentro do filtro vermelho devem ser excluídas da contagem celular. Para confirmar o número de GFP-LLC nos pulmões, um dos lóbulos pode ser usado para análise citométrica de fluxo como demonstrado.Ao tentar este procedimento, é importante lembrar que um procedimento de seção congelada é um método mais preciso para observar a localização exata das células tumorais.

Research

JoVE Journal

Cancer Research

Conditional Knockdown of Gene Expression in Cancer Cell Lines to Study the Recruitment of Monocytes/Macrophages to the Tumor Microenvironment

siRNA and shRNA-mediated knock down (KD) methods of regulating gene expression are invaluable tools for understanding gene and protein function. However, in the case that the KD of the protein of interest has a lethal effect on cells or the anticipated effect of the KD is time-dependent, unconditional KD methods are not appropriate. Conditional systems are more suitable in these cases and have been the subject of much interest. These include Ecdysone-inducible overexpression systems, Cytochrome P-450 induction system1, and the tetracycline regulated gene expression systems. 
The tetracycline regulated gene expression system enables reversible control over protein expression by induction of shRNA expression in the presence of tetracycline. In this protocol, we present an experimental design using functional Tet-ON system in human cancer cell lines for conditional regulation of gene expression. We then demonstrate the use of this system in the study of tumor cell-monocyte interaction.

This protocol serves as a scheme for setting up a functional Tet-ON system in cancer cell lines and its subsequent use, in particular for studying the role of tumor cell-derived proteins in recruitment of monocytes/macrophages to the tumor microenvironment.

Knockdown condicional de expressão gênica em linhas de células de câncer para estudar o recrutamento de monócitos/macrófagos para o microambiente do Tumor

siRNA and shRNA-mediated knock down (KD) methods of regulating gene expression are invaluable tools for understanding gene and protein function. However, ...

Pesquisa do câncer

The Establishment of a Lung Colonization Assay for Circulating Tumor Cell Visualization in Lung Tissues

Metastasis is the major cause of cancer death. The role of circulating tumor cells (CTCs) in promoting cancer metastasis, in which lung colonization by CTCs critically contributes to early lung metastatic processes, has been vigorously investigated. As such, animal models are the only approach that captures the full systemic process of metastasis. Given that problems occur in previous experimental designs for examining the contributions of CTCs to blood vessel extravasation, we established an in vivo lung colonization assay in which a long-term-fluorescence cell-tracer, carboxyfluorescein succinimidyl ester (CFSE), was used to label suspended tumor cells and lung perfusion was performed to clear non-specifically trapped CTCs prior to lung removal, confocal imaging, and quantification. Polymeric fibronectin (polyFN) assembled on CTC surfaces has been found to mediate lung colonization in the final establishment of metastatic tumor tissues. Here, to specifically test the requirement of polyFN assembly on CTCs for lung colonization and extravasation, we performed short term lung colonization assays in which suspended Lewis lung carcinoma cells (LLCs) stably expressing FN-shRNA (shFN) or scramble-shRNA (shScr) and pre-labeled with 20 &#956;M of CFSE were intravenously inoculated into C57BL/6 mice. We successfully demonstrated that the abilities of shFN LLC cells to colonize the mouse lungs were significantly diminished in comparison to shScr LLC cells. Therefore, this short-term methodology may be widely applied to specifically demonstrate the ability of CTCs within the circulation to colonize the lungs.

An animal model is needed to decipher the role of circulating tumor cells (CTCs) in promoting lung colonization during cancer metastasis. Here, we established and successfully performed an in vivo assay to specifically test the requirement of polymeric fibronectin (polyFN) assembly on CTCs for lung colonization.

O estabelecimento de um ensaio de colonização de pulmão para visualização de células de Tumor nos tecidos do pulmão de circulação

Metastasis is the major cause of cancer death. The role of circulating tumor cells (CTCs) in promoting cancer metastasis, in which lung colonization by ...

Acellular and Cellular Lung Model to Study Tumor Metastasis

It is difficult to isolate tumor cells at different points of tumor progression. We created an ex vivo lung model that can show the interaction of tumor cells with a natural matrix and continual flow of nutrients, as well as a model that shows the interaction of tumor cells with normal cellular components and a natural matrix. The acellular ex vivo lung model is created by isolating a rat heart-lung block and removing all the cells using the decellularization process. The right main bronchus is tied off and tumor cells are placed in the trachea by a syringe. The cells move and populate the left lung. The lung is then placed in a bioreactor where the pulmonary artery receives a continual flow of media in a closed circuit. The tumor grown on the left lung is the primary tumor. The tumor cells that are isolated in the circulating media are circulating tumor cells and the tumor cells in the right lung are metastatic lesions. The cellular ex vivo lung model is created by skipping the decellularization process. Each model can be used to answer different research questions.

Here, we present a protocol for an ex vivo lung cancer model that mimics the steps of tumor progression and helps to isolate a primary tumor, circulating tumor cells, and metastatic lesions.

Modelo de pulmão acelular e celular para estudar o Tumor metástase

It is difficult to isolate tumor cells at different points of tumor progression. We created an ex vivo lung model that can show the interaction of tumor ...

Live-Cell Imaging Assays to Study Glioblastoma Brain Tumor Stem Cell Migration and Invasion

Glioblastoma (GBM) is an aggressive brain tumor that is poorly controlled with the currently available treatment options. Key features of GBMs include rapid proliferation and pervasive invasion into the normal brain. Recurrence is thought to result from the presence of radio- and chemo-resistant brain tumor stem cells (BTSCs) that invade away from the initial cancerous mass and, thus, evade surgical resection. Hence, therapies that target BTSCs and their invasive abilities may improve the otherwise poor prognosis of this disease. Our group and others have successfully established and characterized BTSC cultures from GBM patient samples. These BTSC cultures demonstrate fundamental cancer stem cell properties such as clonogenic self-renewal, multi-lineage differentiation, and tumor initiation in immune-deficient mice. In order to improve on the current therapeutic approaches for GBM, a better understanding of the mechanisms of BTSC migration and invasion is necessary. In GBM, the study of migration and invasion is restricted, in part, due to the limitations of existing techniques which do not fully account for the in vitro growth characteristics of BTSCs grown as neurospheres. Here, we describe rapid and quantitative live-cell imaging assays to study both the migration and invasion properties of BTSCs. The first method described is the BTSC migration assay which measures the migration toward a chemoattractant gradient. The second method described is the BTSC invasion assay which images and quantifies a cellular invasion from neurospheres into a matrix. The assays described here are used for the quantification of BTSC migration and invasion over time and under different treatment conditions.

Here, we describe live-cell imaging techniques to quantitatively measure the migration and invasion of glioblastoma brain tumor stem cells over time and under multiple treatment conditions.

Imagem latente da viver-pilha ensaios de migração de células-tronco do estudo Glioblastoma cerebral Tumor e invasão

Glioblastoma (GBM) is an aggressive brain tumor that is poorly controlled with the currently available treatment options. Key features of GBMs include ...

Digital Polymerase Chain Reaction Assay for the Genetic Variation in a Sporadic Familial Adenomatous Polyposis Patient Using the Chip-in-a-tube Format

The quantitative analysis of human genetic variation is crucial for understanding the molecular characteristics of serious medical conditions, such as tumors. Because digital polymerase chain reactions (PCR) enable the precise quantification of DNA copy number variants, they are becoming an essential tool for detecting rare genetic variations, such as drug-resistant mutations. It is expected that molecular diagnoses using digital PCR (dPCR) will be available in clinical practice in the near future; thus, how to efficiently conduct dPCR with human genetic material is a hot topic. Here, we introduce a method to detect Adenomatous polyposis coli (APC) somatic mosaicism using dPCR with the chip-in-a-tube format, which allows eight dPCR reactions to be simultaneously conducted. Care should be taken when filling and sealing the reaction mixture on the chips. This article demonstrates how to avoid the over- and underestimation of positive partitions. Furthermore, we present a simple procedure for collecting the dPCR product from the partitions on the chips, which can then be used to confirm the specific amplification. We hope that this methods report will help promote the dPCR with the chip-in-a-tube method in genetic research.

Digital polymerase chain reaction (PCR) is a useful tool for the high-sensitivity detection of single nucleotide variants and DNA copy number variants. Here, we demonstrate key considerations for measuring rare variants in the human genome using digital PCR with the chip-in-a-tube format.

Ensaio de reação em cadeia de polimerase digital para a variação genética em paciente esporádicos polipose adenomatosa familiar usando o formato de microplaqueta-em-um-tubo

The quantitative analysis of human genetic variation is crucial for understanding the molecular characteristics of serious medical conditions, such as ...

Mesenchymal Stem Cell Isolation from Pulp Tissue and Co-Culture with Cancer Cells to Study Their Interactions

Cancer as a multistep process and complicated disease is not only regulated by individual cell proliferation and growth but also controlled by tumor environment and cell-cell interactions. Identification of cancer and stem cell interactions, including changes in extracellular environment, physical interactions, and secreted factors, might enable the discovery of new therapy options. We combine known co-culture techniques to create a model system for mesenchymal stem cells (MSCs) and cancer cell interactions. In the current study, dental pulp stem cells (DPSCs) and PC-3 prostate cancer cell interactions were examined by direct and indirect co-culture techniques. Condition medium (CM) obtained from DPSCs and 0.4 &#181;m pore sized trans-well membranes were used to study paracrine activity. Co-culture of different cell types together was performed to study direct cell-cell interaction. The results revealed that CM increased cell proliferation and decreased apoptosis in prostate cancer cell cultures. Both CM and trans-well system increased cell migration capacity of PC-3 cells. Cells stained with different membrane dyes were seeded into the same culture vessels, and DPSCs participated in a self-organized structure with PC-3 cells under this direct co-culture condition. Overall, the results indicated that co-culture techniques could be useful for cancer and MSC interactions as a model system.

We provide protocols for evaluation of mesenchymal stem cells isolated from dental pulp and prostate cancer cell interactions based on direct and indirect co-culture methods. Condition medium and trans-well membranes are suitable to analyze indirect paracrine activity. Seeding differentially stained cells together is an appropriate model for direct cell-cell interaction.

Isolamento de células-tronco mesenquimais de tecido pulpar e co-cultura com células cancerosas para estudar suas interações

Cancer as a multistep process and complicated disease is not only regulated by individual cell proliferation and growth but also controlled by tumor ...

Real Time Detection of In Vitro Tumor Cell Apoptosis Induced by CD8+ T Cells to Study Immune Suppressive Functions of Tumor-infiltrating Myeloid Cells

Potentiation of the tumor-killing ability of CD8+ T cells in tumors, along with their efficient tumor infiltration, is a key element of successful immunotherapies. Several studies have indicated that tumor infiltrating myeloid cells (e.g., myeloid-derived suppressor cells (MDSCs) and tumor-associated macrophages (TAMs)) suppress cytotoxicity of CD8+ T cells in the tumor microenvironment, and that targeting these regulatory myeloid cells can improve immunotherapies. Here, we present an in vitro assay system to evaluate immune suppressive effects of monocytic-MDSCs and TAMs on the tumor-killing ability of CD8+ T cells. To this end, we first cultured na&#239;ve splenic CD8+ T cells with anti-CD3/CD28 activating antibodies in the presence or absence of suppressor cells, and then co-cultured the pre-activated T cells with target cancer cells in the presence of a fluorogenic caspase-3 substrate. Fluorescence from the substrate in cancer cells was detected by real-time fluorescence microscopy as an indicator of T-cell induced tumor cell apoptosis. In this assay, we can successfully detect the increase of tumor cell apoptosis by CD8+ T cells and its suppression by pre-culture with TAMs or MDSCs. This functional assay is useful for investigating CD8+ T cell suppression mechanisms by regulatory myeloid cells and identifying druggable targets to overcome it via high throughput screening.

Real Time Detection of In Vitro Tumor Cell Apoptosis Induced by CD8+ T Cells to Study Immune Suppressive Functions of Tumor-infiltrating Myeloid Cells

We describe here a protocol to investigate cytotoxicity of pre-activated CD8+ T cells against cancer cells by detecting apoptotic cancer cells via real-time microscopy. This protocol can investigate mechanisms behind myeloid cell-induced T cell suppression and evaluate compounds aimed at replenishing T cells via blockade of immune suppressive myeloid cells.

Detecção de tempo real em Vitro Tumor celular apoptose induzida por CD8+ T células para estudar as funções imunológicas supressora de Tumor infiltrando células mieloides

Potentiation of the tumor-killing ability of CD8+ T cells in tumors, along with their efficient tumor infiltration, is a key element of successful ...

Semi-automatic PD-L1 Characterization and Enumeration of Circulating Tumor Cells from Non-small Cell Lung Cancer Patients by Immunofluorescence

Circulating tumor cells (CTCs) derived from the primary tumor are shed into the bloodstream or lymphatic system. These rare cells (1&#8722;10 cells per mL of blood) warrant a poor prognosis and are correlated with shorter overall survival in several cancers (e.g., breast, prostate and colorectal). Currently, the anti-EpCAM-coated magnetic bead-based CTC capturing system is the gold standard test approved by the U.S. Food and Drug Administration (FDA) for enumerating CTCs in the bloodstream. This test is based on the use of magnetic beads coated with anti-EpCAM markers, which specifically target epithelial cancer cells. Many studies have illustrated that EpCAM is not the optimal marker for CTC detection. Indeed, CTCs are a heterogeneous subpopulation of cancer cells and are able to undergo an epithelial-to-mesenchymal transition (EMT) associated with metastatic proliferation and invasion. These CTCs are able to reduce the expression of cell surface epithelial marker EpCAM, while increasing mesenchymal markers such as vimentin. To address this technical hurdle, other isolation methods based on physical properties of CTCs have been developed. Microfluidic technologies enable a label-free approach to CTC enrichment from whole blood samples. The spiral microfluidic technology uses the inertial and Dean drag forces with continuous flow in curved channels generated within a spiral microfluidic chip. The cells are separated based on the differences in size and plasticity between normal blood cells and tumoral cells. This protocol details the different steps to characterize the programmed death-ligand 1 (PD-L1) expression of CTCs, combining a spiral microfluidic device with customizable immunofluorescence (IF) marker set.

The characterization of circulating tumor cells (CTCs) is a popular topic in translational research. This protocol describes a semi-automatic immunofluorescence (IF) assay for PD-L1 characterization and enumeration of CTCs in non-small cell lung cancer (NSCLC) patient samples.

Caracterização e enumeração semiautomáticas de PD-L1 de células tumorais circulantes de pacientes com câncer de pulmão de células não pequenas por imunofluorescência

Circulating tumor cells (CTCs) derived from the primary tumor are shed into the bloodstream or lymphatic system. These rare cells (1&#8722;10 cells per mL ...

In Vitro Assay to Study Tumor-macrophage Interaction

Tumor associated macrophages (TAMs) account for a large percentage of cells in the tumor mass for different types of cancers. Glioblastoma (GBM), a malignant brain tumor with no cure, has up to a half the tumor mass TAMs. TAMs can be pro-tumoral or anti-tumoral, depending on the activation of specific genes in the cells. Genetic mutations in the tumors, through regulating cytokine expression, can affect recruitment of TAMs to the tumor microenvironment. Here, we describe a quantitative cell-based assay to assess macrophage recruitment by the conditioned medium from the tumor cells. This assay uses the human macrophage cell line MV-4-11 to study macrophage attraction by the conditioned medium from glioblastoma, allowing for high reproducibility and low variability. Data generated with this assay can contribute to a better understanding of the interaction between the tumor and the tumor microenvironment. Similar assay can be used to assess interaction between the tumor cells and other immune cells, including T cells and natural killer (NK) cells.

This article represents a useful in vitro assay to evaluate the capability of conditioned medium from tumor cells to attract macrophages.

Ensaio in vitro para estudo do tumor-interação macrófago

Tumor associated macrophages (TAMs) account for a large percentage of cells in the tumor mass for different types of cancers. Glioblastoma (GBM), a ...

Detection of Lung Tumor Progression in Mice by Ultrasound Imaging

With ~1.6 million victims per year, lung cancer contributes tremendously to the worldwide burden of cancer. Lung cancer is partly driven by genetic alterations in oncogenes such as the KRAS oncogene, which constitutes ~25% of lung cancer cases. The difficulty in therapeutically targeting KRAS-driven lung cancer partly stems from having poor models that can mimic the progression of the disease in the lab. We describe a method that permits the relative quantification of primary KRAS lung tumors in a Cre-inducible LSL-KRAS G12D mouse model via ultrasound imaging. This method relies on brightness (B)-mode acquisition of the lung parenchyma. Tumors that are initially formed in this model are visualized as B-lines and can be quantified by counting the number of B-lines present in the acquired images. These would represent the relative tumor number formed on the surface of the mouse lung. As the formed tumors develop with time, they are perceived as deep clefts within the lung parenchyma. Since the circumference of the formed tumor is well-defined, calculating the relative tumor volume is achieved by measuring the length and width of the tumor and applying them in the formula used for tumor caliper measurements. Ultrasound imaging is a non-invasive, fast and user-friendly technique that is often used for tumor quantifications in mice. Although artifacts may appear when obtaining ultrasound images, it has been shown that this imaging technique is more advantageous for tumor quantifications in mice compared to other imaging techniques such as computed tomography (CT) imaging and bioluminescence imaging (BLI). Researchers can investigate novel therapeutic targets using this technique by comparing lung tumor initiation and progression between different groups of mice.

This protocol describes the steps taken to induce KRAS lung tumors in mice as well as the quantification of formed tumors by ultrasound imaging. Small tumors are visualized in early timepoints as B-lines. At later timepoints, relative tumor volume measurements are achieved by the measurement tool in the ultrasound software.

Detecção de Progressão do Tumor Pulmonar em Camundongos por ultrassom

With ~1.6 million victims per year, lung cancer contributes tremendously to the worldwide burden of cancer. Lung cancer is partly driven by genetic ...