We would like to thank NIH, LACaTS and Ochsner clinic foundation for the financial support.

Todos os experimentos foram realizados em ratos de acordo com protocolos aprovados pelo Animal Care Institucional e Comissões de Uso (IACUC) da LSU School of Medicine. Todos os instrumentos devem ser autoclavados antes da dissecção. 1. Preparação de células primárias de tumores de mama mouse <ol><li> Use um modelo de camundongo que foi geneticamente modificada com o mouse mamária Tumor poliomavï¿½us Oriente T-Antigen (mouse MMTV-PyMT-transgênica), que se desenvolvem espontaneamente tumores como descrito anteriormente 6. </li><li> Sacrificar os ratinhos com isoflurano (99,9%) e pulverizar etanol 75% para assegurar um ambiente estéril (Figura 1A). </li><li> Abra a pele a partir da área do orifício uretral para o pescoço com uma tesoura. Pin a pele para baixo para permitir fácil acesso aos órgãos (Figura 1B). </li><li> Isolar o tumor da mama mamária frio e lava-se com solução salina tamponada com fosfato estéril (PBS) (pH 7,4) (Figura 1C). </li><li> Transferência do tumor auma placa de cultura de 10 centímetros de tecido estéril e cortá-la com uma lâmina de barbear estéril e tesoura para aproximadamente 1 mm3 peças. Os passos subsequentes devem ser realizados numa câmara de fluxo laminar estéril. </li><li> Incubar o tecido tumoral picada com colagenase dissolvido em meio DMEM isento de soro com uma concentração final de 1 mg / ml num agitador rotativo durante 2 horas a 37 ° C. Centrifugar a suspensão do tecido do tumor durante 3 min a 200 x g. NOTA: A incubação da colagenase é essencial para a dissociação enzimática do tecido. </li><li> Descartar o sobrenadante e lavar o precipitado três vezes com PBS (pH 7,4) por centrifugação durante 3 minutos a 200 x g. Após a lavagem final, decanta-se o sobrenadante. </li><li> Ressuspender o tecido com 2 ml de EDTA de tripsina durante 5 min a 37 ° C, enquanto de nutação. Centrifugar a suspensão durante 3 minutos a 200 xg e repetir as lavagens. </li><li> Ressuspender o sedimento de tecido em meio de crescimento normal (DMEM, FBS a 10%, 2X pen / strep) numa placa de 10 centímetros. Mudançaa mídia todos os dias para os próximos 3 dias. Células de cultura de células até que o número desejado é obtido. NOTA: Aproximadamente 1x10 7 células serão isoladas a partir deste procedimento. Outros modelos tumorigénese mamário de ratinho, tal como MMTV-neu, dar menor rendimento de células quando comparado com MMTV-PyMT. Quando utilizando modelos que produzem um rendimento inferior, é benéfico para começar com um maior células tumorais e de cultura mais longos. </li></ol> 2. Rato Lung Extração de Visualize Lung Metástase <ol><li> Antes da extração do pulmão, do fígado e remover o diafragma. Desalojar as costelas sem perturbar os pulmões. </li><li> Com um par de tesouras finas, abrir a parte superior da traqueia, que está mais perto da veia jugular. </li><li> Usando um catéter, injectar um agente, tal como 1 ml de Z-fix ou Índia tinta através da traqueia para encher os pulmões (Figura 2A). Incorporar o Z-fix Pulmões em parafina. </li><li> De-manchar os pulmões injetados com nanquim em solução de Fekete(100 ml de álcool a 70%, 10 mL de formalina a 10% tamponada, e 5 ml de ácido acético glacial), durante 5 min. Definir nódulos tumorais em locais secundários com um ≥ 0,5 mm de diâmetro, determinar os nódulos como metástase. NOTA: Devido ao bloqueio brônquios e bronquíolos pelo tumor, nódulos tumorais não pode absorver 15% da tinta da Índia, e, assim, tecido pulmonar normal será em preto e nódulos tumorais será na cor branca 7. Isto irá permitir a visualização de nódulos tumorais individuais (Figura 2B). </li></ol> 3. Preparar mouse embrionárias fibroblastos (MEFs) a partir de embriões de camundongos <ol><li> Sacrifício camundongos grávidas com isoflurano (99,9%) e spray de etanol de 75% para garantir um ambiente estéril. </li><li> Abra a pele a partir da área do orifício uretral para o pescoço com uma tesoura e isolar os embriões do útero. </li><li> Tenha cuidado para não perturbar os embriões ao abrir a pele. </li><li> Remova os cornos uterinos e enxaguá-los em ste friorile PBS (pH 7,4). </li><li> Separa-se a partir de embriões placenta sua muito cuidadosamente e embriões lugar numa placa de 10 centímetros contendo PBS gelado (pH 7,4). </li><li> Remover a cabeça, fígado e intestino a partir do embrião e colocar a parte restante em uma placa de cultura de tecidos de 12 poços contendo PBS (pH 7,4). </li><li> Transferir o corpo do embrião para uma outra placa de 12 poços contendo EDTA de tripsina e cortados em pedaços pequenos (~ 1 mm3) utilizando uma lâmina de barbear esterilizada e tesoura. Incubar o material cortado com 5 ml de EDTA de tripsina durante 5 min a 37 ° C. </li><li> Inactivar a tripsina por adição de 1 ml de Soro Fetal Bovino (FBS) para os embriões picados. Centrifugar a suspensão a 200 xg velocidade durante 10 minutos, remover o sobrenadante cuidadosamente, ressuspender o sedimento com 1 ml de meio DMEM morno e transferir todo o conteúdo para um prato de 10 centímetros contendo 10 ml de DMEM (com 20% de FBS e 2X de Penicilina / Estreptomicina ). </li><li> Mudar a forma todos os dias durante dois dias. Cultura das células até célula desejadanúmero é alcançado. </li></ol>

<ol>
	<li>Minn, A. 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=Genes+that+mediate+breast+cancer+metastasis+to+lung.">Genes that mediate breast cancer metastasis to lung.</a> Natur. 436 (7050), 518-524 (2005).</li><li>Poste, G., Fidler, I. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+pathogenesis+of+cancer+metastasis.">The pathogenesis of cancer metastasis.</a> Natur. 283 (5743), 139-146 (1980).</li><li>Wan, L. <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+Moving+New+Biological+Insights+into+the+Clinic.">Tumor Metastasis Moving New Biological Insights into the Clinic.</a> Nat Med. 19 (11), 1450-1464 (2013).</li><li>Bergers, G., Benjamin, L. E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Tumorigenesis+and+the+angiogenic+switch.">Tumorigenesis and the angiogenic switch.</a> Nat Rev Cancer. 3 (6), 401-410 (2003).</li><li>Frese, K. K., Tuveson, D. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Maximizing+mouse+cancer+models.">Maximizing mouse cancer models.</a> Nat Rev Cancer. 7 (9), 654-658 (2007).</li><li>Guy, C. T., Cardiff, R. D., Muller, W. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Induction+of+mammary+tumors+by+expression+of+polyomavirus+middle+T+oncogene:+a+transgenic+mouse+model+for+metastatic+disease.">Induction of mammary tumors by expression of polyomavirus middle T oncogene: a transgenic mouse model for metastatic disease.</a> Mol Cell Biol. 12 (3), 954-961 (1992).</li><li>Wexler, H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Accurate+Identification+of+Experimental+Pulmonary+Metastases.">Accurate Identification of Experimental Pulmonary Metastases.</a> J Natl Cancer Inst. 36 (4), 641-645 (1966).</li><li>Boczkowski, D., Nair, S. K., Nam, J. H., Lyerly, H. K., Gilboa, E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Induction+of+tumor+immunity+and+cytotoxic+T+lymphocyte+responses+using+dendritic+cells+transfected+with+messenger+RNA+amplified+from+tumor+cells.">Induction of tumor immunity and cytotoxic T lymphocyte responses using dendritic cells transfected with messenger RNA amplified from tumor cells.</a> Cancer Res. 60 (4), 1028-1034 (2000).</li><li>Vargo-Gogola, T., Rosen, J. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Modelling+breast+cancer:+one+size+does+not+fit+all.">Modelling breast cancer: one size does not fit all.</a> Nat Rev Cancer. 7 (9), 659-672 (2007).</li><li>Watts, A. M., Kennedy, R. C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Quantitation+of+Tumor+Foci+in+an+Experimental+Murine+Tumor+Model+Using+Computer-Assisted+Video+Imaging.">Quantitation of Tumor Foci in an Experimental Murine Tumor Model Using Computer-Assisted Video Imaging.</a> Anal Bioche. 256 (2), 217-219 (1998).</li><li>Rosenberg, S. 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=Regression+of+Established+Pulmonary+Metastases+and+Subcutaneous+Tumor+Mediated+by+the+Systemic+Administration+of+High-Dose+Recombinant+Interleukin+2.">Regression of Established Pulmonary Metastases and Subcutaneous Tumor Mediated by the Systemic Administration of High-Dose Recombinant Interleukin 2.</a> J Exp Me. 161 (5), 1169-1188 (1985).</li><li>Fantozzi, A., Christofori, G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Mouse+models+of+breast+cancer+metastasis.">Mouse models of breast cancer metastasis.</a> Breast Cancer Re. 8 (4), 212 (2006).</li><li>Veer, L., 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=Gene+expression+profiling+predicts+clinical+outcome+of+breast+cancer.">Gene expression profiling predicts clinical outcome of breast cancer.</a> Nature. 415 (6871), 530-536 (2002).</li></ol>

Os autores não têm divulgações.

Este protocolo é para isolar células primárias de um tumor fresco mouse. Os lisados ​​preparados a partir de este método são úteis para a proteína, ADN e análise de ARN. As células cancerosas de tumor da mama primário frequentemente metastizar para o cérebro, pulmão e osso 1. Inclui-se uma técnica para extrair o pulmão para a detecção de metástases. A coloração do pulmão com uma mancha de tinta vai permitir a visualização dos nódulos tumorais como pode ser visto na Figura 2B. Que fixa os pulmões em solução Z-fix nos permitirá fazer secções de pulmões, e manchar com anticorpos que são apropriados para estudar mecanismos metastáticos. Também está incluído um protocolo para o isolamento de fibroblastos embrionários de ratinho. Isto é útil para comparar a expressão de genes das células de tumor primárias com o fibroblasto embrionário no mesmo tipo de animal. Na preparação de células primárias e MEFs, a etapa mais crítica é a trituração do material. Sem repartição adequada, loo número de células W será alcançado. Se uma baixa contagem de células é conseguida, o protocolo pode ainda ser seguido, mas as células terão de ser cultivadas durante um longo período de tempo .. Na extracção do pulmão, a coloração adequada e descoloração é essencial para permitir a visualização do nódulo de tumor. Para extrair RNA / proteína a partir de pulmões, que vai ser bom para usar pulmões que são imaculado e não fixo. No entanto, o RNA pode ser extraído a partir de tecidos fixos, bem 8. Desde a fase metastática do câncer de mama representa a maior ameaça para o indivíduo afetado 2, é importante visualizar todos os componentes de tumorigênese da mama. Um desafio importante na compreensão dos mecanismos de progressão do câncer de mama é a disponibilidade de modelos que recapitulam a progressão da doença 9. A elucidação dos mecanismos moleculares da tumorigénese da mama e de metástases são alcançados através da utilização de modelos animais, tais como ratinhos 9, 10. As formas mais comuns para induzir compue tumores mamários são manipular geneticamente os ratos com mutações de oncogenes ou supressores de tumor pré-disposição, a introdução de substâncias cancerígenas, e injetando células cancerosas altamente invasivos 10-12. Tumores obtidos podem depois ser ainda analisados ​​quanto à expressão do gene. Para a investigação do cancro da mama, perfil de expressão gênica é importante, uma vez que prevê a evolução clínica do paciente 13. Algumas limitações existem com o modelo do rato de estudar tumorigênese mamária. Embora ratinhos partes moleculares semelhanças fisiológicas e com seres humanos, eles nem sempre recapitular todos os aspectos de doenças humanas 5. Isto deve ser tomado em consideração quando se utiliza certos ratos geneticamente modificados. No geral, modelos de ratos proporcionam uma forma mais realista para analisar mamário de ratinho tumorigenesis sobre outros modelos atuais como cultura de tecidos e tumores humanos isolados. Tomados em conjunto, este protocolo permite a uma investigação mais aprofundada dos diferentes aspectostumorigenesis de mama.

Metastasis is the final step in the progression of breast cancer 1. It involves a series of steps in which malignant cells are released from the primary tumor and disseminated to other organs 2. The cells must be able to intravasate, survive in circulation, extravasate to distant organs, and survive in that new organ system 3. Each step in tumorigenesis is tightly controlled by cells through various genetic and epigenetic changes 4. To study the mechanisms of breast cancer tumorigenesis, mouse model systems have been utilized due to their short lifespan, small size and fast breeding time. Some major advantages of using mouse models in cancer research are the molecular and physiological similarities they share with humans 5. 
Established mouse and human cell lines have been used extensively in breast cancer research. Although we can obtain some information about the steps in metastasis using these cells, genetically manipulated animal models with tumor suppressors/oncogenes will give far more information about tumor development and metastasis starting from the embryonic stage. Thus, with these mouse models, we can obtain genetic and developmental regulation of tumor growth. Furthermore, the tumor microenvironment also plays an important role in tumor cell gene expression and it can be difficult to mimic the same scenario with studies using established cell lines. Primary human mammary tumors can also be used to study mouse mammary tumorigenesis. The main disadvantage of using isolated breast tumors is that this newly implanted tumor does not have the mouse&#8217;s vasculature and lymphatic tissue. Whereas the genetic mouse model systems for studying mammary tumorigenesis will allow us to monitor the steps of metastasis, analyze the tumor microenvironment, and access to the entire body 5.
The overall goal of this protocol is to study breast tumorigenesis in mice. It is known that breast cancers typically metastasize to the brain, lung and bone. This protocol allows for the isolation of primary mammary tumor cells, as well as, studying breast cancer metastasis to the lung. Furthermore, another protocol for analyzing mouse embryonic fibroblasts (MEFs) from the mouse embryo is included. Together, these techniques are useful in studying mouse mammary tumorigenesis.

<table border="0" cellpadding="0" cellspacing="0">
	<tbody>
		<tr>
			<td>DMEM</td>
			<td>HyClone</td>
			<td>SH30243.01</td>
			<td>Store at 4 &#176;C</td>
		</tr>
		<tr>
			<td>0.05% Trypsin-EDTA</td>
			<td>Life&#160; technologies</td>
			<td>25300-062</td>
			<td>Store at &#8211; 20 &#176;C</td>
		</tr>
		<tr>
			<td>Collagenase Type IV</td>
			<td>Sigma-Aldrich</td>
			<td>C5138</td>
			<td>Store at &#8211; 20 &#176;C</td>
		</tr>
		<tr>
			<td>Hyaluronidase</td>
			<td>Sigma-Aldrich</td>
			<td>H3506</td>
			<td>Store at &#8211; 20 &#176;C</td>
		</tr>
		<tr>
			<td>Pen Strep</td>
			<td>Life&#160; technologies</td>
			<td>15140-122</td>
			<td>Store at 4 &#176;C</td>
		</tr>
		<tr>
			<td>Fetal Bovine Serum (FBS)</td>
			<td>Gemini Bio-Products</td>
			<td>100-106</td>
			<td>Store at &#8211; 80 &#176;C</td>
		</tr>
		<tr>
			<td>Z-fix</td>
			<td>ANATECH</td>
			<td>#174</td>
			<td>Store at room temperature</td>
		</tr>
		<tr>
			<td>India Ink</td>
			<td>Yasutomo</td>
			<td></td>
			<td>Store at room temperature</td>
		</tr>
		<tr>
			<td>AERRANE (Isoflurane)</td>
			<td>Baxter</td>
			<td>NDC 10019-773-60</td>
			<td>Store at room temperature</td>
		</tr>
		<tr>
			<td>Ethanol</td>
			<td>EMD</td>
			<td>AX0441-3</td>
			<td>Store at room temperature</td>
		</tr>
	</tbody>
</table>

primary tumor and mef cell isolation to study lung metastasis

In breast tumorigenesis, the metastatic stage of the disease poses the greatest threat to the affected individual. Normal breast cells with altered genotypes now possess the ability to invade and survive in other tissues. In this protocol, mouse mammary tumors are removed and primary cells are prepared from tumors. The cells isolated from this procedure are then available for gene profiling experiments. For successful metastasis, these cells must be able to intravasate, survive in circulation, extravasate to distant organs, and survive in that new organ system. The lungs are the typical target of breast cancer metastasis. A set of genes have been discovered that mediates the selectivity of metastasis to the lung. Here we describe a method of studying lung metastasis from a genetically engineered mouse model.. Furthermore, another protocol for analyzing mouse embryonic fibroblasts (MEFs) from the mouse embryo is included. MEF cells from the same animal type provide a clue of non-cancer cell gene expression. Together, these techniques are useful in studying mouse mammary tumorigenesis, its associated signaling mechanisms and pathways of the abnormalities in embryos.

A fase de progressão do tumor em que a sacrificar o animal depende do estudo particular e orientações IACUC. Na Figura 1A, um velho C57BL / 6 do mouse 100 dias com o mouse mamária Tumor poliomavï¿½us Oriente T-Antigen (MMTV-PyMT) foi sacrificado em três meses. A pele foi aberta a partir da área do orifício uretral para o pescoço com as tesouras e a pele foi fixado para baixo para permitir o fácil acesso a órgãos como mostrado na Figura 1B. Isto permitiu um fácil acesso ao tumor que foi obtido na Figura 1C. As células primárias obtidas a partir dos tumores são visualizados na Figura 1D. Uma vez que muitos genes medeiam a metástase do cancro da mama para o pulmão 1, extraiu-se que os pulmões (Figura 2A) para estudar o processo metastático. O pulmão foi inflado com Z-fix e corados com nanquim (Figura 2B) para visualizar os nódulos tumorais. A Figura 3 mostra rato FIBR embrionárias<html> oblasts isolado a partir de embriões de camundongos FVB tensão. <img alt="Figura 1" src="/files/ftp_upload/52609/52609fig1.jpg" /> Figura 1. Preparação de células primárias de tumores de mama. (A) A idade do rato fêmea com o Polioma Oriente T-Antigen (PyMT) 100 dias foi sacrificado. (B) A pele foi fixado para baixo para permitir fácil acesso ao tumor mamário. (C) O tumor de mama foi cortado do animal (D). As células primárias isoladas foram cultivadas em Dulbecco Modified Eagle Médium (DMEM) suplementado com 10% de soro bovino fetal e antibióticos (barra de escala: 100? M). As imagens mostram as células no dia 3. <a href="https://www-jove-com.remotexs.ntu.edu.sg/files/ftp_upload/52609/52609fig1large.jpg" target="_blank">Por favor clique aqui para ver uma versão maior desta figura.</a> fazer upload / 52.609 / 52609fig2.jpg &quot;/&gt; Figura 2. extracção de pulmão do rato para visualizar a metástase pulmonar. (A) O pulmão foi inflado com Z-fix e (B) corada com tinta nanquim para visualizar nódulos tumorais (barra de escala: 500 mm). <a href="https://www-jove-com.remotexs.ntu.edu.sg/files/ftp_upload/52609/52609fig2large.jpg" target="_blank">Por favor clique aqui para ver uma versão maior desta figura.</a> <img alt="Figura 3" src="/files/ftp_upload/52609/52609fig3.jpg" /> . Figura 3. Preparar mouse embrionárias fibroblastos (MEFs) a partir de embriões de camundongos MEF células foram extraídas de um embrião de rato FVB (barra de escala: 100 M). <a href="https://www-jove-com.remotexs.ntu.edu.sg/files/ftp_upload/52609/52609fig3large.jpg" target="_blank">Por favor clique aqui para ver uma versão maior desta figura.</a>

Watch this Scientific Journal Video about Primary Tumor and MEF Cell Isolation to Study Lung Metastasis at JoVE.com

Primary Tumor and MEF Cell Isolation to Study Lung Metastasis

The goal of this protocol is to study breast tumorigenesis. With this technique, mouse mammary tumors are removed and primary cells are prepared from tumors. A lung extraction protocol is included for studying lung metastasis. Furthermore, another protocol for analyzing mouse embryonic fibroblasts from the mouse embryo is included.

Tumor primário e isolamento de células MEF para o Estudo de metástases pulmonares

In breast tumorigenesis, the metastatic stage of the disease poses the greatest threat to the affected individual. Normal breast cells with altered ...

primary-tumor-and-mef-cell-isolation-to-study-lung-metastasis

Nanyang Technological University

Research

JoVE Journal

Medicine

15.7K visualizações.  Louisiana State University Health Sciences Center. The goal of this protocol is to study breast tumorigenesis. With this technique, mouse mammary tumors are removed and primary cells are prepared from tumors. A lung extraction protocol is included for studying lung metastasis. Furthermore, another protocol for analyzing mouse embryonic fibroblasts from the mouse embryo is included.

Vídeo: Primary Tumor and MEF Cell Isolation to Study Lung Metastasis

An In Vitro System to Study Tumor Dormancy and the Switch to Metastatic Growth

Recurrence of breast cancer often follows a long latent period in which there are no signs of cancer, and metastases may not become clinically apparent until many years after removal of the primary tumor and adjuvant therapy. A likely explanation of this phenomenon is that tumor cells have seeded metastatic sites, are resistant to conventional therapies, and remain dormant for long periods of time 1-4.
The existence of dormant cancer cells at secondary sites has been described previously as quiescent solitary cells that neither proliferate nor undergo apoptosis 5-7. Moreover, these solitary cells has been shown to disseminate from the primary tumor at an early stage of disease progression 8-10 and reside growth-arrested in the patients' bone marrow, blood and lymph nodes 1,4,11. Therefore, understanding mechanisms that regulate dormancy or the switch to a proliferative state is critical for discovering novel targets and interventions to prevent disease recurrence. However, unraveling the mechanisms regulating the switch from tumor dormancy to metastatic growth has been hampered by the lack of available model systems.
in vivo and ex vivo model systems to study metastatic progression of tumor cells have been described previously 1,12-14. However these model systems have not provided in real time and in a high throughput manner mechanistic insights into what triggers the emergence of solitary dormant tumor cells to proliferate as metastatic disease. We have recently developed a 3D in vitro system to model the in vivo growth characteristics of cells that exhibit either dormant (D2.OR, MCF7, K7M2-AS.46) or proliferative (D2A1, MDA-MB-231, K7M2) metastatic behavior in vivo . We demonstrated that tumor cells that exhibit dormancy in vivo at a metastatic site remain quiescent when cultured in a 3-dimension (3D) basement membrane extract (BME), whereas cells highly metastatic in vivo readily proliferate in 3D culture after variable, but relatively short periods of quiescence. Importantly by utilizing the 3D in vitro model system we demonstrated for the first time that the ECM composition plays an important role in regulating whether dormant tumor cells will switch to a proliferative state and have confirmed this in in vivo studies15-17. Hence, the model system described in this report provides an in vitro method to model tumor dormancy and study the transition to proliferative growth induced by the microenvironment.

An In Vitro System to Study Tumor Dormancy and the Switch to Metastatic Growth

A modified 3-D in vitro system is presented in which growth characteristics of several tumor cell lines in reconstituted basement membrane correlate with the dormant or proliferative behavior of the tumor cells at a metastatic secondary site in vivo.

Um In Vitro Sistema para Estudo de dormência Tumor ea Mude para o crescimento metastático

Recurrence of breast cancer often follows a long latent period in which there are no signs of cancer, and metastases may not become clinically apparent ...

Medicina

Processing of Primary Brain Tumor Tissue for Stem Cell Assays and Flow Sorting

Brain tumors are typically comprised of morphologically diverse cells that express a variety of neural lineage markers. Only a relatively small fraction of cells in the tumor with stem cell properties, termed brain tumor initiating cells (BTICs), possess an ability to differentiate along multiple lineages, self-renew, and initiate tumors in vivo. We applied culture conditions originally used for normal neural stem cells (NSCs) to a variety of human brain tumors and found that this culture method specifically selects for stem-like populations. Serum-free medium (NSC) allows for the maintenance of an undifferentiated stem cell state, and the addition of bFGF and EGF allows for the proliferation of multi-potent, self-renewing, and expandable tumorspheres.
To further characterize each tumor's BTIC population, we evaluate cell surface markers by flow cytometry. We may also sort populations of interest for more specific characterization. Self-renewal assays are performed on single BTICs sorted into 96 well plates; the formation of tumorspheres following incubation at 37 &deg;C indicates the presence of a stem or progenitor cell. Multiple cell numbers of a particular population can also be sorted in different wells for limiting dilution analysis, to analyze self-renewal capacity. We can also study differential gene expression within a particular cell population by using single cell RT-PCR.
The following protocols describe our procedures for the dissociation and culturing of primary human samples to enrich for BTIC populations, as well as the dissociation of tumorspheres. Also included are protocols for staining for flow cytometry analysis or sorting, self-renewal assays, and single cell RT-PCR.

The identification of brain tumor initiating cells (BTICs), the rare cells within a heterogeneous tumor possessing stem cell properties, provides new insights into human brain tumor pathogenesis. We have refined specific culture conditions to enrich for BTICs, and we routinely use flow cytometry to further enrich these populations. Self-renewal assays and transcript analysis by single cell RT-PCR can subsequently be performed on these isolated cells.

Processamento de tecido primário do tumor cerebral para Ensaios de Células Tronco e Fluxo de Classificando

Brain tumors are typically comprised of morphologically diverse cells that express a variety of neural lineage markers. Only a relatively small fraction ...

Human Neuroendocrine Tumor Cell Lines as a Three-Dimensional Model for the Study of Human Neuroendocrine Tumor Therapy

Neuroendocrine tumors (NETs) are rare tumors, with an incidence of two per 100,&#x200A;000 individuals per year, and they account for 0.5% of all human malignancies.1 Other than surgery for the minority of patients who present with localized disease, there is little or no survival benefit of systemic therapy. Therefore, there is a great need to better understand the biology of NETs, and in particular define new therapeutic targets for patients with nonresectable or metastatic neuroendocrine tumors. 3D cell culture is becoming a popular method for drug screening due to its relevance in modeling the in vivo tumor tissue organization and microenvironment.2,3 The 3D multicellular spheroids could provide valuable information in a more timely and less expensive manner than directly proceeding from 2D cell culture experiments to animal (murine) models.
To facilitate the discovery of new therapeutics for NET patients, we have developed an in vitro 3D multicellular spheroids model using the human NET cell lines. The NET cells are plated in a non-adhesive agarose-coated 24-well plate and incubated under physiological conditions (5% CO2, 37 &deg;C) with a very slow agitation for 16-24 hr after plating. The cells form multicellular spheroids starting on the 3rd or 4th day. The spheroids become more spherical by the 6th day, at which point the drug treatments are initiated. The efficacy of the drug treatments on the NET spheroids is monitored based on the morphology, shape and size of the spheroids with a phase-contrast light microscope. The size of the spheroids is estimated automatically using a custom-developed MATLAB program based on an active contour algorithm. Further, we demonstrate a simple method to process the HistoGel embedding on these 3D spheroids, allowing the use of standard histological and immunohistochemical techniques. 
This is the first report on generating 3D spheroids using NET cell lines to examine the effect of therapeutic drugs. We have also performed histology on these 3D spheroids, and displayed an example of a single drug's effect on growth and proliferation of the NET spheroids. Our results support that the NET spheroids are valuable for further studies of NET biology and drug development.

We present a simple agarose overlay platform to grow 3D multicellular spheroids using neuroendocrine cancer cell lines. This method provides a very convenient way to examine the effect of therapeutic drugs on the neuroendocrine tumor cells. It could also help us establish human neuroendocrine tumor spheroids for cancer therapy.

Humanos Linhas tumor neuroendócrino de células como um modelo tridimensional para o estudo da terapia de tumores humanos Neuroendócrino

Neuroendocrine tumors (NETs) are rare tumors, with an incidence of two per 100,&#x200A;000 individuals per year, and they account for 0.5% of all human ...

Patient Derived Cell Culture and Isolation of CD133+ Putative Cancer Stem Cells from Melanoma

Despite improved treatments options for melanoma available today, patients with advanced malignant melanoma still have a poor prognosis for progression-free and overall survival. Therefore, translational research needs to provide further molecular evidence to improve targeted therapies for malignant melanomas. In the past, oncogenic mechanisms related to melanoma were extensively studied in established cell lines. On the way to more personalized treatment regimens based on individual genetic profiles, we propose to use patient-derived cell lines instead of generic cell lines. Together with high quality clinical data, especially on patient follow-up, these cells will be instrumental to better understand the molecular mechanisms behind melanoma progression.
Here, we report the establishment of primary melanoma cultures from dissected fresh tumor tissue. This procedure includes mincing and dissociation of the tissue into single cells, removal of contaminations with erythrocytes and fibroblasts as well as primary culture and reliable verification of the cells' melanoma origin.
Recent reports revealed that melanomas, like the majority of tumors, harbor a small subpopulation of cancer stem cells (CSCs), which seem to exclusively fuel tumor initiation and progression towards the metastatic state. One of the key markers for CSC identification and isolation in melanoma is CD133. To isolate CD133+ CSCs from primary melanoma cultures, we have modified and optimized the Magnetic-Activated Cell Sorting (MACS) procedure from Miltenyi resulting in high sorting purity and viability of CD133+ CSCs and CD133- bulk, which can be cultivated and functionally analyzed thereafter.

Patient Derived Cell Culture and Isolation of CD133+ Putative Cancer Stem Cells from Melanoma

This article describes the preparation of freshly obtained melanoma tissue into primary cell cultures, and how to remove contaminations of erythrocytes and fibroblasts from the tumor cells. Finally, we describe how CD133+ putative melanoma stem cells are sorted from the CD133- bulk using Magnetic Activated Cell Sorting (MACS).

Cultura de Células e Isolamento paciente Derivado de CD133<sup&gt; +</sup&gt; Células-tronco de câncer putativos Melanoma

Despite improved treatments options for melanoma available today, patients with advanced malignant melanoma still have a poor prognosis for ...

A Novel High-resolution In vivo Imaging Technique to Study the Dynamic Response of Intracranial Structures to Tumor Growth and Therapeutics

We have successfully integrated previously established Intracranial window (ICW) technology 1-4 with intravital 2-photon confocal microscopy to develop a novel platform that allows for direct long-term visualization of tissue structure changes intracranially. Imaging at a single cell resolution in a real-time fashion provides supplementary dynamic information beyond that provided by standard end-point histological analysis, which looks solely at 'snap-shot' cross sections of tissue.
Establishing this intravital imaging technique in fluorescent chimeric mice, we are able to image four fluorescent channels simultaneously. By incorporating fluorescently labeled cells, such as GFP+ bone marrow, it is possible to track the fate of these cells studying their long-term migration, integration and differentiation within tissue. Further integration of a secondary reporter cell, such as an mCherry glioma tumor line, allows for characterization of cell:cell interactions. Structural changes in the tissue microenvironment can be highlighted through the addition of intra-vital dyes and antibodies, for example CD31 tagged antibodies and Dextran molecules.
Moreover, we describe the combination of our ICW imaging model with a small animal micro-irradiator that provides stereotactic irradiation, creating a platform through which the dynamic tissue changes that occur following the administration of ionizing irradiation can be assessed.
Current limitations of our model include penetrance of the microscope, which is limited to a depth of up to 900 &mu;m from the sub cortical surface, limiting imaging to the dorsal axis of the brain. The presence of the skull bone makes the ICW a more challenging technical procedure, compared to the more established and utilized chamber models currently used to study mammary tissue and fat pads 5-7. In addition, the ICW provides many challenges when optimizing the imaging.

A Novel High-resolution In vivo Imaging Technique to Study the Dynamic Response of Intracranial Structures to Tumor Growth and Therapeutics

We describe a novel in vivo imaging technique that couples fluorescent chimeric mice with intracranial windows and high-resolution 2-photon microscopy. This imaging platform aids studies of dynamic changes in brain tissue and microvasculature, at a single-cell level, following pathological insults and is adaptable to assess intracranial drug delivery and distribution.

A Novel de alta resolução<em&gt; In vivo</em&gt; Técnica de Imagem para estudar a resposta dinâmica de estruturas intracranianas ao crescimento do tumor e Terapêutica

We have successfully integrated previously established Intracranial window (ICW) technology 1-4 with intravital 2-photon confocal microscopy to develop a ...

Noninvasive Intratracheal Intubation to Study the Pathology and Physiology of Mouse Lung

The use of a model that mimics the condition of lung diseases in humans is critical for studying the pathophysiology and/or etiology of a particular disease and for developing therapeutic intervention. With the increasing availability of knockout and transgenic derivatives, together with a vast amount of genetic information, mice provide one of the best models to study the molecular mechanisms underlying the pathology and physiology of lung diseases. Inhalation, intranasal instillation, intratracheal instillation, and intratracheal intubation are the most widely used techniques by a number of investigators to administer materials of interest to mouse lungs. There are pros and cons for each technique depending on the goals of a study. Here a noninvasive intratracheal intubation method that can directly deliver exogenous materials to mouse lungs is presented. This technique was applied to administer bleomycin to mouse lungs as a model to study pulmonary fibrosis.

The use of a model that mimics the condition of lung diseases in humans is critical for studying the pathophysiology and/or etiology of a particular disease and for developing therapeutic intervention. Here a noninvasive intratracheal intubation method that can directly deliver exogenous materials to mouse lungs is presented.

Não invasiva Intratraqueal intubação para estudar a Patologia e Fisiologia do Rato Lung

The use of a model that mimics the condition of lung diseases in humans is critical for studying the pathophysiology and/or etiology of a particular ...

Implantation of Fibrin Gel on Mouse Lung to Study Lung-specific Angiogenesis

Recent significant advances in stem cell research and bioengineering techniques have made great progress in utilizing biomaterials to regenerate and repair damage in simple tissues in the orthopedic and periodontal fields. However, attempts to regenerate the structures and functions of more complex three-dimensional (3D) organs such as lungs have not been very successful because the biological processes of organ regeneration have not been well explored. It is becoming clear that angiogenesis, the formation of new blood vessels, plays key roles in organ regeneration. Newly formed vasculatures not only deliver oxygen, nutrients and various cell components that are required for organ regeneration but also provide instructive signals to the regenerating local tissues. Therefore, to successfully regenerate lungs in an adult, it is necessary to recapitulate the lung-specific microenvironments in which angiogenesis drives regeneration of local lung tissues. Although conventional in vivo angiogenesis assays, such as subcutaneous implantation of extracellular matrix (ECM)-rich hydrogels (e.g., fibrin or collagen gels or Matrigel - ECM protein mixture secreted by Engelbreth-Holm-Swarm mouse sarcoma cells), are extensively utilized to explore the general mechanisms of angiogenesis, lung-specific angiogenesis has not been well characterized because methods for orthotopic implantation of biomaterials in the lung have not been well established. The goal of this protocol is to introduce a unique method to implant fibrin gel on the lung surface of living adult mouse, allowing for the successful recapitulation of host lung-derived angiogenesis inside the gel. This approach enables researchers to explore the mechanisms by which the lung-specific microenvironment controls angiogenesis and alveolar regeneration in both normal and pathological conditions. Since implanted biomaterials release and supply physical and chemical signals to adjacent lung tissues, implantation of these biomaterials on diseased lung can potentially normalize the adjacent diseased tissues, enabling researchers to develop new therapeutic approaches for various types of lung diseases.

Recapitulation of the organ-specific microenvironment, which stimulates local angiogenesis, is indispensable for successful regeneration of damaged tissues. This report demonstrates a novel method to implant fibrin gels on the lung surface of living mouse in order to explore how the lung-specific microenvironment modulates angiogenesis and alveolar regeneration in adult mouse.

Implantação de fibrina Gel no tapete do pulmão para o Estudo de angiogênese Lung-specific

Recent significant advances in stem cell research and bioengineering techniques have made great progress in utilizing biomaterials to regenerate and ...

Cardiac Catheterization in Mice to Measure the Pressure Volume Relationship: Investigating the Bowditch Effect

Animal models that mimic human cardiac disorders have been created to test potential therapeutic strategies. A key component to evaluating these strategies is to examine their effects on heart function. There are several techniques to measure in vivo cardiac mechanics (e.g., echocardiography, pressure/volume relations, etc.). Compared to echocardiography, real-time left ventricular (LV) pressure/volume analysis via catheterization is more precise and insightful in assessing LV function. Additionally, LV pressure/volume analysis provides the ability to instantaneously record changes during manipulations of contractility (e.g., &#946;-adrenergic stimulation) and pathological insults (e.g., ischemia/reperfusion injury). In addition to the maximum (+dP/dt) and minimum (-dP/dt) rate of pressure change in the LV, an accurate assessment of LV function via several load-independent indexes (e.g., end systolic pressure volume relationship and preload recruitable stroke work) can be attained. Heart rate has a significant effect on LV contractility such that an increase in the heart rate is the primary mechanism to increase cardiac output (i.e., Bowditch effect). Thus, when comparing hemodynamics between experimental groups, it is necessary to have similar heart rates. Furthermore, a hallmark of many cardiomyopathy models is a decrease in contractile reserve (i.e., decreased Bowditch effect). Consequently, vital information can be obtained by determining the effects of increasing heart rate on contractility. Our and others data has demonstrated that the neuronal nitric oxide synthase (NOS1) knockout mouse has decreased contractility. Here we describe the procedure of measuring LV pressure/volume with increasing heart rates using the NOS1 knockout mouse model.

This article describes the measurement of murine left ventricular function via pressure/volume analysis at different heart rates.

O cateterismo cardíaco em camundongos para medir o volume Pressão do relacionamento: Investigando o efeito Bowditch

Animal models that mimic human cardiac disorders have been created to test potential therapeutic strategies. A key component to evaluating these ...

Isolation and Culture Expansion of Tumor-specific Endothelial Cells

Freshly isolated tumor-specific endothelial cells (TEC) can be used to explore molecular mechanisms of tumor angiogenesis and serve as an in vitro model for developing new angiogenesis inhibitors for cancer. However, long-term in vitro expansion of murine endothelial cells (EC) is challenging due to phenotypic drift in culture (endothelial-to-mesenchymal transition) and contamination with non-EC. This is especially true for TEC which are readily outcompeted by co-purified fibroblasts or tumor cells in culture. Here, a high fidelity isolation method that takes advantage of immunomagnetic enrichment coupled with colony selection and in vitro expansion is described. This approach generates pure EC fractions that are entirely free of contaminating stromal or tumor cells. It is also shown that lineage-traced Cdh5cre:ZsGreenl/s/l reporter mice, used with the protocol described herein, are a valuable tool to verify cell purity as the isolated EC colonies from these mice show durable and brilliant ZsGreen fluorescence in culture.

We report a reliable method to isolate and culture primary tumor-specific endothelial cells from genetically engineered mouse models.

Isolamento e Cultura de Expansão de células endoteliais específicos de tumores

Freshly isolated tumor-specific endothelial cells (TEC) can be used to explore molecular mechanisms of tumor angiogenesis and serve as an in vitro model ...

Evaluation of Lung Metastasis in Mouse Mammary Tumor Models by Quantitative Real-time PCR

Metastatic disease is the spread of malignant tumor cells from the primary cancer site to a distant organ and is the primary cause of cancer associated death 1. Common sites of metastatic spread include lung, lymph node, brain, and bone 2. Mechanisms that drive metastasis are intense areas of cancer research. Consequently, effective assays to measure metastatic burden in distant sites of metastasis are instrumental for cancer research. Evaluation of lung metastases in mammary tumor models is generally performed by gross qualitative observation of lung tissue following dissection. Quantitative methods of evaluating metastasis are currently limited to ex vivo and in vivo imaging based techniques that require user defined parameters. Many of these techniques are at the whole organism level rather than the cellular level 3-6. Although newer imaging methods utilizing multi-photon microscopy are able to evaluate metastasis at the cellular level 7, these highly elegant procedures are more suited to evaluating mechanisms of dissemination rather than quantitative assessment of metastatic burden. Here, a simple in vitro method to quantitatively assess metastasis is presented. Using quantitative Real-time PCR (QRT-PCR), tumor cell specific mRNA can be detected within the mouse lung tissue.

This protocol describes how to use quantitative Real-time PCR (QRT-PCR) to detect tumor cell specific mRNA representing metastasis within the mouse lung tissue.

Avaliação de metástases pulmonares em Rato mamárias tumorais Models por Quantitative PCR em tempo real

Metastatic disease is the spread of malignant tumor cells from the primary cancer site to a distant organ and is the primary cause of cancer associated ...