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1. Ensaio clonogénico <ol><li> Preparar um único suspensões de células de linhas celulares do cancro da mama dependentes de estrogénio de células MCF-7 e T47D utilizando os passos descritos abaixo <ol><li> Aspirar o meio de cultura (DMEM / 10% inactivado pelo calor soro fetal de vitelo / glutamina e Pen / Strep) a partir de 10 cm do tecido placa de cultura, que é não confluentes mais de 50% com células T-47D MCF-7 ou. Lavar com PBS. Incubar com tripsina a 0,25% / EDTA 2,21 mM dissolvido em DMEM de alto teor de glucose a 37 ° C durante 1-4 min. </li><li> Confira as células em um mínimo de intervalos sob um microscópio de contraste de fase para garantir uma distribuição única célula. Volte a suspender as células com uma pipeta 2 ml por pipetagem cima e para baixo várias vezes para interromper contato célula-célula para atingir, um status de única célula quase invariável. </li><li> Continue a incubar células em tripsina a 37 ° C por até 4 min, se você observar aglomerados de células depois de apenas 2 min de incubação. Não use essas células para estudos clonogénicos se eles permanecem aderentes ao each outro após 4 min de tripsinização porque o erro será introduzido no rendimento número colônia. NOTA: Se as células são aglutinados, o número de colônias formadas irá reflectir o produto de menos células do que o número incubadas. Se as células são tratadas com tripsina excessivamente, o seu potencial clonogénico pode ser diminuída. </li><li> Prepara-se uma suspensão de células única de 1500 células / ml de meio de cultura para placas de 24 cavidades, ou menos, de (+ 500 células / ml, dependendo do tipo de célula ou o número de passagem), através de diluições em série em um tubo principal que contém todo o volume necessário para a todas as variáveis ​​no experimento. NOTA: O objectivo é uma densidade final de células de 800 células / cm2 (gama de aproximadamente 500 a 1100 células / cm2). O objectivo é produzir aproximadamente 100 + 50 colónias, que permite a contagem relativamente fácil, impede aglomeração e permite colónias suficientes para resultar em diferenças estatisticamente significativas quando as colónias são aumentadas ou diminuídas por perturba experimentalções. </li></ol></li><li> Incube as células a clonogénico de densidade usando etapas descritas abaixo <ol><li> Incubar as células em poços em quadruplicado em 24 placas revestidas com fibronectina a uma densidade de 1500 células clonogénicas / poço a partir de um tubo de suspensão de células individuais mestre de 1500 células / ml. Triturar o meio contendo células com uma pipeta 5 ml através da elaboração de 3 ml e 1 ml de meio de distribuição em cada um dos dois poços. NOTA: A fibronectina revestido placas devem ser compradas pré-revestido a partir de um fornecedor comercial. Placas de revestimento fora de uma qualidade controlada, processo resulta automatizados em uma superfície irregular inadequada para este ensaio. </li><li> Misture a suspensão por pipetagem cima e para baixo com uma pipeta de 5 ml, 3 ml elaborar de suspensão de células e preencher 2 poços com 1 ml cada. Encha apenas dois poços de uma só vez a partir de uma pipeta. Retorne o volume restante na pipeta à suspensão de células no tubo principal, voltar a suspender as células novamente pipetando cima e para baixo e elaborar outros 3 ml para encher outro 2 welsl com 1 ml cada. NOTA: mistura contínua do tubo principal é necessário porque as células irão sedimentar continuamente. Desenhando-se um volume suficiente para encher apenas dois poços é necessário adicionar o número de células semelhantes a cada poço, porque as células sedimentar na pipeta bem. </li><li> Trabalhar rapidamente para distribuir as grandes volumes de células porque as células que permitem a sentar-se em suspensão à temperatura ambiente e concentração de CO 2 vai modulam suas potenciais (observações não publicadas) clonogénicos. </li><li> Otimizar a distribuição espacial das células durante o ato de pipetar-los em poços para ensaios de colónias. Fazê-lo pipetando lentamente a suspensão contendo a concentração final de células no meio do poço. Não sujeite a placa para promover o movimento antes que as células se depositam no fundo. Não rodar a placa circular porque mistura irá eficazmente centrifugar as células para o perímetro das densidades celulares elevadas e assim criando colónias confluentes incontáveis ​​a 6 dias. NOTA: Não misture a menos que necessário uma vez que este é menos desejável que nenhuma mistura em tudo depois de introduzir o volume com as células em suspensão. Se é necessário para misturar as células, fazê-lo em movimento a placa para trás e para a frente em direcções perpendiculares, enquanto que repousa sobre uma superfície plana. </li><li> Incubar as células a 37 ° C, 5% de CO 2, sem mudança de meio, durante 6 dias. O pequeno número de células em um poço após 6 dias não vai ter impacto significativo na composição de nutrientes ou de citoquinas nem o pH do meio original. </li><li> Design o decurso de tempo do ensaio do seguinte modo: Incubar as células em fibronectina substratos revestidos no dia 1. Substitua meio existente, com 1 ml de meio fresco ou meio fresco contendo 10 ng / ml no dia 0. As células mancha no dia 6 como abaixo de 2 FGF- em 1.4). Realizar quaisquer perturbações experimentais no dia 3, como abaixo de 1.3). </li></ol></li><li> Configurar Perturbations experimentais de sinalização molecular ou Moléculas de Adesão <ol><li> No dia 3, adicionar 10056; l de uma solução contendo 10x da concentração final pretendida do agente perturbador para a forma de 1 ml nos poços. Não misture. Continue-se a incubar as células a 37 ° C, 5% de CO 2 por 3 dias adicionais. NOTA: agentes Perturbando pode incluir uma variedade de agentes bloqueadores e inibidores de moléculas de adesão, receptores ou outras proteínas de superfície, os inibidores de vias de sinalização intracelulares, moléculas, factores, co-factores ou proteínas estruturais, que podem desempenhar um papel no apoio ao estado dormente. </li><li> Colónias mancha no dia 6, como segue. </li></ol></li><li> Colônias Mancha <ol><li> Células mancha após 6 dias em cultura com um recém-feitos 0,1% violeta de cristal em 2% de etanol / 10 mM borato de sódio solução (pH 9,0). Meios Aspirar e adicionar uma solução de violeta de cristal ml a cada poço durante 20 minutos. </li><li> Lavar as placas por imersão com as aberturas de poços virados para baixo em um ângulo agudo em um balde de gelo repleto de execução contínua da torneiraágua na pia. Incline a placa em um ângulo horizontal, uma vez debaixo de água, bem abrindo para baixo, e em seguida, incline para trás a um ângulo agudo ao remover em um movimento que flui suave. </li><li> Repetir a imersão 2 ou 3 vezes até que a água no fundo dos poços não é mais azul. Lavagens vigorosa pode remover as células ou as colónias que são menos aderente devido à intervenção experimental, adicionando significativamente ao erro na contagem e os dados. </li><li> Chapas secas durante a noite, colocando-os de cabeça para baixo em toalhas na bancada adjacente às suas correspondentes tampas marcadas. </li></ol></li><li> Contagem de colónias <ol><li> Contar o número de colónias em crescimento e latentes em cada poço após 6 dias de incubação, a coloração e secagem. Contagem das colónias optimamente a 40X em um microscópio de contraste de fase invertida. Contagem de colônias de&gt; 30 células como crescer e colônias de 12 ou menos células, com o aspecto morfológico de tamanho muito grande em comparação com células em crescimento, grande Expacitoplasma NDED com grande citoplasma para núcleo rácios, mostrado na Figura 1 7,15. NOTA: Conjuntos de 13-29 células normalmente não são contados como eles não são muito frequentes em ensaios de dormência simples. Eles podem ser contadas se perturbações deslocar o potencial de crescimento da utilização de células em crescimento ou dormentes. Estes resultados terão então de ser correlacionado com significado biológico. </li></ol></li></ol> 2. clonogénico Incubação de Estudos de imunofluorescência <ol><li> Ajustar o número de células de aproximadamente 7,500-8,000 células / poço em placas de 6 cavidades, para corresponder à célula números de área de superfície / análogo a 24 experiências bem. </li><li> Coloque uma rodada, estéril, tampa de deslizamento revestido de fibronectina em cada base poço de placas de 6 poços para estudos de imagem antes da adição de células. Pipetar as células em volumes de 3 mL em cada poço 2 poços de uma vez em concentrações descritas, tal como descrito para as experiências clonogénicas acima em 1.2). </li><li> Incubar as célulasdurante 6 dias, como acima em 1.2.4 e 1.2.5. Adicionar factores perturbadores no dia 3 a 10X a concentração em volumes de 300 ul, tal como descrito nos procedimentos de ensaio de colónia em 1.3). </li><li> Células mancha no dia 6, com anticorpos para moléculas de adesão celular tais como as integrinas α4, α5, α6, β1, β3, por exemplo, moléculas de adesão focal complexos FAK, paxilina e vinculina, por exemplo, proteínas envolvidas na motilidade, tais como α-tubulina, por exemplo, membros da via de sinalização, tal como fosfo-Akt, fosfo-ERK, fosfo-p38, fosfo-JNK, por exemplo, ou qualquer outra proteína que é o alvo de investigação para o seu papel em dormência, utilizando técnicas padrão para directa ou indirecta imunofluorescência. <ol><li> Retirar as lâminas com uma pinça dia 6. Fix em acetona / metanol 1: 1 a -20 ° C durante 20 min e o ar seco. Um fixador alternativo, tal como paraformaldeído, pode ser utilizado, se necessário. Permeabilizar as células com 0,1% de Triton X-100, 0,1% de citrato de sódio durante 2 min fou detecção de antigénios intracelulares. Lavar as células com PBS. </li><li> Para a coloração indirecta immunofluorecence, bloco desliza durante 1 h à temperatura ambiente com BSA a 5% ou com 10% de soro pré-imune das espécies em que o anticorpo secundário foi gerado. </li><li> Incubar durante a noite a 4 ° C com os anticorpos primários para a célula moléculas de adesão, moléculas complexas focais, a sinalização da via de membros ou qualquer outra proteína que é o alvo de investigação para o seu papel em dormência diluído para as diluições específicas recomendadas pelo fabricante em PBS 0,1% de Triton X -100. </li><li> Lavar 3 vezes com PBS. Incubar lamelas com anticorpos conjugados com fluoróforo à temperatura ambiente durante 2 h. Como um exemplo, Alexa Fluor 488 de burro anti-IgG de ratinho de anticorpos podem ser utilizados para detectar anticorpos primários monoclonais de murino. Mount lamelas lado célula para baixo em lâminas de vidro, utilizando um agente antifade com DAPI. Selar os perímetros com unha polonês. </li><li> Para imunofluorescência direta, realizar a BSAbloqueio como acima no ponto 2.4.2), incubar com o anticorpo primário conjugado com fluoróforo durante a noite a 4 ° C. Lavar 3 vezes com PBS. Incubar as lâminas com um agente antifade e Dapi e selo com unha polonês. </li><li> Bandejas tampa deslizante com folha de alumínio e armazenar a 4 ° C para geração de imagens ea fotografia a qualquer hora até várias semanas depois. Veja fotos e células utilizando quaisquer sistemas de imagens microscópicas de fluorescência equipado com uma câmera de 1000X ampliação. </li><li> Para a coloração de actina fibrilar, bloco desliza em 1% de albumina de soro bovino (BSA) durante 30 min e incubar em BODIPY FL-Phallacidin (verde) ou rodamina-faloidina (vermelho) à temperatura ambiente durante 20 min. Adicionar um agente antifade e selar como acima. </li></ol></li></ol> 3. clonogénico Incubação de Estudos Moleculares <ol><li> Western Blots <ol><li> Incubar ER + do câncer de mama células MCF-7 ou T47D em densidades clonogénicos de 20.000 células / placa de 60 mm e 50.000 células / placa 100mm em fibronecplacas a 37 ° C em 5% de CO 2 revestido de estanho. </li><li> Incubar as células em densidades ligeiramente superiores de 75.000 células / 100 mm placa para estudos moleculares que exijam montantes mg para proteína de lisados. Use até dez placas por ponto experimental para coletar proteína suficiente para estudos moleculares utilizando Western blot ou para isolamento de RNA de transferência de Northern. </li><li> O número de células de gel com base de carregamento é um complemento necessário para comparar a expressão da proteína em células de cultivo e dormentes vastamente diferentes tamanhos. Recolher as células por trypsinizing e contagem de uma alíquota num hemocitómetro em 0,2% de Azul de Tripano, para preparação de lisados ​​de Western blot em vez de raspar as células com uma única lâmina de borda. </li><li> Células de centrífuga a 10.000 xg durante 2 minutos, retirar o suporte por aspiração, adicionar 200 ul de tampão de lise, sonicar as células em tampão de lise e determinar a concentração de proteína. </li><li> Calcula-se a quantidade de proteína por célula, dividindo a produção de proteína ao número de célulasque gerou esse montante. Carregar o lisado para cada poço de géis de poliacrilamida separadas que representa tanto a) quantidades equivalentes de proteína e b) as quantidades de proteína que representam o número de células equivalentes. Pelo menos 25 mg de proteína deve ser carregado em cada poço. NOTA: Isto irá permitir comparações entre crescimento e dormentes células, que são significativamente diferentes em tamanho e conteúdo de proteína (Figura 1). </li></ol></li><li> Citometria de Fluxo <ol><li> Recolher as células a partir de placas de 100 mm por tripsinização, como em 3.1 e analisar por células activadas por fluorescência (FACS padrão) usando protocolos de coloração por imunofluorescência primário ou secundário tanto para antigénios intracelulares ou extracelulares, como descrito em 2.4. NOTA: Desanexando células a partir das placas de cultura de tecidos por tripsinização não afecta a concentração de proteínas de membrana, conforme determinado por marcação com anticorpos. </li></ol></li></ol>

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M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Differential+temporal+and+spatial+gene+expression+of+fibroblast+growth+factor+family+members+during+mouse+mammary+gland+development.">Differential temporal and spatial gene expression of fibroblast growth factor family members during mouse mammary gland development.</a> Molecular Endocrinology. 8 (2), 218-229 (1994).</li><li>Plath, 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=Expression+and+localization+of+members+of+the+fibroblast+growth+factor+family+in+the+bovine+mammary+gland.">Expression and localization of members of the fibroblast growth factor family in the bovine mammary gland.</a> J Dairy Science. 81 (10), 2604-2613 (1998).</li><li>Lavandero, S., Chappuzeau, A., Sapag-Hagar, M., Oka, T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=In+vivo+and+in+vitro+evidence+of+basic+fibroblast+growth+factor+action+in+mouse+mammary+gland+development.">In vivo and in vitro evidence of basic fibroblast growth factor action in mouse mammary gland development.</a> FEBS letters. 439 (3), 351-356 (1998).</li><li>Sinowatz, F., Schams, D., Plath, A., Kolle, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Expression+and+localization+of+growth+factors+during+mammary+gland+development.">Expression and localization of growth factors during mammary gland development.</a> Adv in Exp Med &amp; Biol. 480, 19-27 (2000).</li><li>Korah, R., Sysounthone, V., Scheff, E., Wieder, R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Intracellular+FGF-2+promotes+differentiation+in+T47-D+breast+cancer+cells.">Intracellular FGF-2 promotes differentiation in T47-D breast cancer cells.</a> Biochem Biophys Res Comm. 277 (1), 255-260 (2000).</li><li>Korah, R., Das, K., Lindy, M. E., Hameed, M., Wieder, R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Co-ordinate+loss+of+FGF-2+and+laminin+5+expression+during+neoplastic+progression+of+mammary+duct+epithelium.">Co-ordinate loss of FGF-2 and laminin 5 expression during neoplastic progression of mammary duct epithelium.</a> Human Pathology. 38 (1), 154-160 (2007).</li><li>Wieder, R., 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=Overexpression+of+basic+fibroblast+growth+factor+in+MCF-7+human+breast+cancer+cells:+lack+of+correlation+between+inhibition+of+cell+growth+and+MAP+kinase+activation.">Overexpression of basic fibroblast growth factor in MCF-7 human breast cancer cells: lack of correlation between inhibition of cell growth and MAP kinase activation.</a> J. Cellular Physiology. 177, 411-425 (1998).</li><li>Brunner, G., Gabrilove, J., Rifkin, D. B., Wilson, E. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Phospholipase+C+release+of+basic+fibroblast+growth+factor+from+human+bone+marrow+cultures+as+a+biologically+active+complex+with+a+phosphatidylinositol-anchored+heparan+sulfate+proteoglycan.">Phospholipase C release of basic fibroblast growth factor from human bone marrow cultures as a biologically active complex with a phosphatidylinositol-anchored heparan sulfate proteoglycan.</a> J Cell Biol. 114 (6), 1275-1283 (1991).</li><li>Wilson, E. L., Rifkin, D. B., Kelly, F., Hannocks, M. J., Gabrilove, J. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Basic+fibroblast+growth+factor+stimulates+myelopoiesis+in+long-term+human+bone+marrow+cultures.">Basic fibroblast growth factor stimulates myelopoiesis in long-term human bone marrow cultures.</a> Blood. 77 (5), 954-960 (1991).</li><li>Gupta, P., McCarthy, J. B., Verfaillie, C. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Stromal+fibroblast+heparan+sulfate+is+required+for+cytokine-mediated+ex+vivo+maintenance+of+human+long-term+culture-initiating+cells.">Stromal fibroblast heparan sulfate is required for cytokine-mediated ex vivo maintenance of human long-term culture-initiating cells.</a> Blood. 87 (8), 3229-3236 (1996).</li><li>Chatterjee, M., van Golen, K. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Farnesyl+transferase+inhibitor+treatment+of+breast+cancer+cells+leads+to+altered+RhoA+and+RhoC+GTPase+activity+and+induces+a+dormant+phenotype.">Farnesyl transferase inhibitor treatment of breast cancer cells leads to altered RhoA and RhoC GTPase activity and induces a dormant phenotype.</a> Int J Cancer. 129 (1), 61-69 (2011).</li><li>Korah, R., Sysounthone, V., Golowa, Y., Wieder, R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Basic+fibroblast+growth+factor+confers+a+more+differentiated+phenotype+in+MDA-MB-231+human+breast+cancer+cells.">Basic fibroblast growth factor confers a more differentiated phenotype in MDA-MB-231 human breast cancer cells.</a> Cancer Res. 60 (3), 733-740 (2000).</li><li>Dontu, G., 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=In+vitro+propagation+and+transcriptional+profiling+of+human+mammary+stem/progenitor+cells.">In vitro propagation and transcriptional profiling of human mammary stem/progenitor cells.</a> Genes &amp; Dev. 17 (10), 1253-1270 (2003).</li><li>Tivari, S., Lu, H., Dasgupta, T., Wieder, R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Reactivation+of+dormant+estrogen-dependent+breast+cancer+micrometastases+by+bone+marrow+stromal+injury+in+an+in+vitro+model+of+dormancy.">Reactivation of dormant estrogen-dependent breast cancer micrometastases by bone marrow stromal injury in an in vitro model of dormancy.</a> Proceedings of the 105th Annual Meeting of the American Association for Cancer Research. , (2014).</li></ol>

Compatível com o Departamento de Defesa Grants DAMD17-01-C-0343 e DAMD17-03-1-0524, a Comissão Estado de Nova Jersey em Cancer Research 02-1140-CCR-E0 ea Ruth Goldberg Estrin Memorial para Pesquisa do Câncer (RW)

O nosso modelo é composta por vários elementos chave de dormência na medula óssea. É composto de estrogénio células sensíveis, que são do tipo susceptíveis de permanecer dormentes na medula por períodos prolongados 10, que consiste de fibronectina, um elemento estrutural chave da medula, o FGF-2, um factor de crescimento abundantemente sintetizado pelo estroma da medula óssea e fortemente depositado na matriz extracelular da medula óssea 31,32 e incubação de células clonogénicas, e...

Células de cancro da mama metastizar para a medula óssea antes de a doença é detectável 1, assim que os tumores se desenvolvem pequenos vasos sanguíneos 2,3. O processo metastático é rápida, mas ineficiente. Células entram os novos vasos sanguíneos rapidamente, a milhões por dia 4, mas poucos sobrevivem a viagem para órgãos distantes 5. No entanto, algumas micrometástases sobreviver no osso e pode ser encontrado como células individuais ou pequenos aglomerados de células nos aspirados de medula óssea de pacientes recentemente diagnosticados 1. Estas células resistem à quimioterapia adjuvante, que é administrado pela própria finalidade de eliminá-los 6. Esta resistência é dotado, substancialmente, por sobrevivência sinalização iniciada por interacções com o microambiente da medula óssea 7,8. Micrometástases pode ser encontrado em cerca de um terço das mulheres com câncer de mama localizado e representam um indicador independente de sobrevida quando analisados ​​por análise univariada 9. Alguns micrometástases são o crescimento iniciado, mas padrões de retorno depende do tipo de célula. Pacientes com câncer de mama triplo negativo tendem a recorrer entre 1 a 4 anos, sugerindo pobre controle sobre o estado de dormência. Outros tipos de células, incluindo ER / PR +, células podem permanecer dormentes por até 20 anos, com uma taxa constante e contínuo de recorrência 10. Embora as diferenças em dormência assinaturas de expressão gênica entre ER- linhas de células de mama e tumores ER + e refletem diferentes potenciais de dormência 11, interacções com estroma da medula óssea provavelmente representam um contributo significativo para a dormência. O estudo de dormência in vivo é excepcionalmente difícil porque micrometástases são raros e estão em desvantagem por células hematopoiéticas em mais de 10 vezes de 6. Assim, os modelos relevantes devem ser gerados que fornecem dados in vitro que pode sugerir mecanismos e gerar hipóteses testáveis ​​in vivo. Uma série de modelos de dormência, incluindo mathemodelos matical 12,13, modelos in vitro, in vivo 7,8,14,15 modelos de xenotransplante de 16, combinações de in vitro e modelos de xenotransplante de 17,18 e tumorais e metástases modelos espontâneos 19, têm rendido alguns insights sobre a dormência célula cancerosa 20 . Cada um desses modelos têm as suas próprias limitações e são em si principalmente útil para gerar hipóteses sobre a sinalização molecular e interações que regem a dormência a ser testada em modelos mais biologicamente relevantes. Com o objetivo geral de definir os mecanismos moleculares de dormência, as interações com o microambiente que resulta na paragem do ciclo, rediferenciação e resistência e os mecanismos terapêuticos que resultam em recorrência em células ER +, desenvolvemos um modelo in vitro que fornece selecionado elementos relevantes da estromal microambiente 7. Este modelo, embora relativamente escassa em seu componentes, é suficientemente robusto para permitir investigadores para derivar mecanismos moleculares específicos que afectam funções significativas de dormência. Estas experiências gerar hipóteses que podem ser directamente testados in vivo. O modelo baseia-se em alguns elementos-chave que demonstraram ser relevante em dormência. Eles incluem a utilização de células de cancro da mama dependentes de estrogénio, a cultura de células a uma densidade clonogénico onde a sua interacção é principalmente com o substrato e os componentes solúveis do meio, um substrato fibronectina e a presença do factor de crescimento básico de fibroblastos (FGF-2) no meio. Foram caracterizados os mecanismos que governam o sistema in vitro, incluindo a indução de paragem do ciclo celular por FGF-2 21, mediada através de TGFp 22, a sobrevivência a sinalização através de PI3-quinase ERK 7,8 e 8 e diferenciação morfogénica para um fenótipo epitelial, que dependia RhoA inactivação, integrina45; 5β1 regulação positiva e ligadura de fibronectina do estroma para a sobrevivência 7,15 (Figura 1). Os efeitos do ciclo celular in vitro de FGF-2 em células MCF-7 em concentrações começam pelo menos um log inferior a 10 ng / mL 21,23. A lógica baseou-se no controlo temporal da expressão de FGF-2 que regula a morfogénese ductal da mama, de expansão cíclica e recessão em um certo número de sistemas de mamíferos 24-27. Nós demonstramos que o FGF-2 induz a diferenciação, incluindo morfogénese ductal in cultura 3D 28, e que a expressão de FGF-2 são geralmente perdido com a transformação maligna de tumores humanos 29. A expressão de FGR1 permaneceu intacto em carcinomas da mama examinados 29 e MCF-7 de células continuam a expressar todos os quatro receptores de FGF 30. No contexto da dormência, o FGF-2 é exportada por e fortemente depositado em estroma de medula óssea 31,32 onde funciona na preservação de células-tronco hematopoiéticas 33. Nós demmonstrado que o FGF-2 induz um estado dormente em ER + do câncer de mama células cultivadas em substratos fibronectina, também abundantes na medula, onde induz a diferenciação morphogenic 7. No modelo, as células de cancro da mama são crescimento inibido, inactivar Rho A através do RhoGap Graf, redifferentiate a um fenótipo epitelial e re-express integrinas α5β1 lost com a progressão maligna. Ligam-se fibronectina através integrina α5β1 e activar a sobrevivência de sinalização que torná-las resistentes à terapia citotóxica 7,8,15 (Figura 1). A inibição de Rho GTPases classe tem sido demonstrado anteriormente para induzir um fenótipo dormente 34. Aqui vamos delinear os procedimentos específicos que permitam aos investigadores estabelecer o modelo e estudar os mecanismos moleculares e celulares específicas que regulam a dormência das células ER + do câncer de mama. Nas experiências aqui apresentadas para ilustrar o uso do modelo, Que orientada via PI3K (Figura 1B) com um inibidor Akt e um inibidor de PI3K e todos os membros da família Rho (Figura 1B) com um inibidor da pan-Rho e Rho cinase um (ROCK) inibidor.

<table border="0" cellpadding="0" cellspacing="0">
	<tbody>
		<tr>
			<td>MCF-7 cells</td>
			<td>ATCC</td>
			<td>HTB-22</td>
			<td></td>
		</tr>
		<tr>
			<td>T47D cells&#160;</td>
			<td>ATCC</td>
			<td>HTB-123</td>
			<td></td>
		</tr>
		<tr>
			<td>BD BioCoat Fibronectin 24 Well Clear Flat Bottom TC-Treated Multiwell Plate</td>
			<td>Corning</td>
			<td>354411</td>
			<td></td>
		</tr>
		<tr>
			<td>BD BioCoat Fibronectin 60 mm Culture Dishes</td>
			<td>Corning</td>
			<td>354403</td>
			<td></td>
		</tr>
		<tr>
			<td>BD BioCoat Fibronectin 100 mm Culture Dishes</td>
			<td>Corning</td>
			<td>354451</td>
			<td></td>
		</tr>
		<tr>
			<td>BD BioCoat 22x22mm #1 Glass Coverslip with a uniform application of human fibronectin</td>
			<td>Corning</td>
			<td>354088</td>
			<td></td>
		</tr>
		<tr>
			<td>6 Well tissue culture plate</td>
			<td>CellTreat</td>
			<td>229106</td>
			<td></td>
		</tr>
		<tr>
			<td>Dulbecco Modified Eagle Medium High Glucose 10X Powder</td>
			<td>Corning Life Sciences</td>
			<td>50-013-PB</td>
			<td></td>
		</tr>
		<tr>
			<td>Heat Inactivated, Fetal Bovine Serum</td>
			<td>Serum Source International</td>
			<td>FB02-500HI</td>
			<td></td>
		</tr>
		<tr>
			<td>0.25% Trypsin/2.21 mM EDTA</td>
			<td>Corning</td>
			<td>25-053-CI</td>
			<td></td>
		</tr>
		<tr>
			<td>Penicillin-Streptomycin Solution, 100X</td>
			<td>Corning</td>
			<td>30-002-CI</td>
			<td></td>
		</tr>
		<tr>
			<td>L-Glutamine, 100x, Liquid</td>
			<td>Corning</td>
			<td>25-005-CI</td>
			<td></td>
		</tr>
		<tr>
			<td>Recombinant Human FGF&#160;basic</td>
			<td>R&#38;D Systems</td>
			<td>234-FSE-025</td>
			<td></td>
		</tr>
		<tr>
			<td>Akt Inhibitor (1L6-Hydroxymethyl-chiro-inositol-2-(R)-2-O-methyl-3-O-octadecyl-sn-glycerocarbonate)</td>
			<td>CalBiochem</td>
			<td>124005</td>
			<td></td>
		</tr>
		<tr>
			<td>LY294002&#160;</td>
			<td>CalBiochem</td>
			<td>19-142</td>
			<td>Chenical PI3K inhibitor</td>
		</tr>
		<tr>
			<td>C3 transferase&#160;</td>
			<td>Cytoskeleton</td>
			<td>CTO3</td>
			<td>Inhibits RhoA, RhoB, and RhoC, but not related GTPases such as Cdc42 or Rac1</td>
		</tr>
		<tr>
			<td>Y-27632 dihydrochloride&#160;</td>
			<td>Santa Cruz Biotechnology</td>
			<td>129830-28-2</td>
			<td></td>
		</tr>
		<tr>
			<td>BODIPY FL-Phallacidin (green)&#160;</td>
			<td>Molecular Probes</td>
			<td>B607</td>
			<td>Fluorochrome for fibrillar actin staining</td>
		</tr>
		<tr>
			<td>BODIPY FL-Rhodamine phalloidin (red)&#160;</td>
			<td>Molecular Probes</td>
			<td>R415</td>
			<td>Fluorochrome for fibrillar actin staining</td>
		</tr>
		<tr>
			<td>Alexa Fluor 488 Donkey anti-Mouse IgG Antibody, ReadyProbes Reagent&#160;</td>
			<td>Molecular Probes</td>
			<td>R37114</td>
			<td></td>
		</tr>
		<tr>
			<td>ProLong Gold Antifade Mountant with DAPI&#160;</td>
			<td>Molecular Probes</td>
			<td>P-36931</td>
			<td></td>
		</tr>
	</tbody>
</table>

an in vitro dormancy model of estrogen-sensitive breast cancer in the bone marrow: a tool for molecular mechanism studies and hypothesis generation

The study of breast cancer dormancy in the bone marrow is an exceptionally difficult undertaking due to the complexity of the interactions of dormant cells with their microenvironment, their rarity and the overwhelming excess of hematopoietic cells. Towards this end, we developed an in vitro 2D clonogenic model of dormancy of estrogen-sensitive breast cancer cells in the bone marrow. The model consists of a few key elements necessary for dormancy. These include 1) the use of estrogen sensitive breast cancer cells, which are the type likely to remain dormant for extended periods, 2) incubation of cells at clonogenic density, where the structural interaction of each cell is primarily with the substratum, 3) fibronectin, a key structural element of the marrow and 4) FGF-2, a growth factor abundantly synthesized by bone marrow stromal cells and heavily deposited in the extracellular matrix. Cells incubated with FGF-2 form dormant clones after 6 days, which consist of 12 or less cells that have a distinct flat appearance, are significantly larger and more spread out than growing cells and have large cytoplasm to nucleus ratios. In contrast, cells incubated without FGF-2 form primarily growing colonies consisting of >30 relatively small cells. Perturbations of the system with antibodies, inhibitors, peptides or nucleic acids on day 3 after incubation can significantly affect various phenotypic and molecular aspects of the dormant cells at 6 days and can be used to assess the roles of membrane-localized or intracellular molecules, factors or signaling pathways on the dormant state or survival of dormant cells. While recognizing the in vitro nature of the assay, it can function as a highly useful tool to glean significant information about the molecular mechanisms necessary for establishment and survival of dormant cells. This data can be used to generate hypotheses to be tested in vivo models.

<html> As experiências foram conduzidas de recapitular o ensaio. O curso do tempo da experiência é mostrado na Figura 2A. As células são incubadas a densidade clonogénico no dia -1, é adicionado FGF-2 em meio fresco no dia 0 e as células são cultivadas até ao dia 6, quando eles são coradas e as colónias são contadas. Quaisquer perturbações do sistema são administrados no dia 3 em volumes de 100 uL a 10X a concentração final desejada. A Figura 2B mostra a aparência típ...

Watch this Scientific Journal Video about An In Vitro Dormancy Model of Estrogen-sensitive Breast Cancer in the Bone Marrow: A Tool for Molecular Mechanism Studies and Hypothesis Generation at JoVE.co

An In Vitro Dormancy Model of Estrogen-sensitive Breast Cancer in the Bone Marrow: A Tool for Molecular Mechanism Studies and Hypothesis Generation

We developed an in vitro model of dormancy in the bone marrow for estrogen-sensitive breast cancer cells. The goal of this protocol is to demonstrate use of the model for the study of the molecular and cellular biology of dormancy and for generation of hypotheses for subsequent testing in vivo.

Um<em&gt; In Vitro</em&gt; Dormência Modelo de câncer de mama estrogênio-sensíveis na medula óssea: Uma Ferramenta para Estudos Moleculares Mecanismo e Hipótese Geração

The study of breast cancer dormancy in the bone marrow is an exceptionally difficult undertaking due to the complexity of the interactions of dormant ...

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An In Vitro Dormancy Model of Estrogen-sensitive Breast Cancer in the Bone Marrow: A Tool for Molecular Mechanism Studies and Hypothesis Generation

8.2K visualizações.  Rutgers New Jersey Medical School. We developed an in vitro model of dormancy in the bone marrow for estrogen-sensitive breast cancer cells. The goal of this protocol is to demonstrate use of the model for the study of the molecular and cellular biology of dormancy and for generation of hypotheses for subsequent testing in vivo. 

Vídeo: An In Vitro Dormancy Model of Estrogen-sensitive Breast Cancer in the Bone Marrow: A Tool for Molecular Mechanism Studies and Hypothesis Generation

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

Multi-photon Imaging of Tumor Cell Invasion in an Orthotopic Mouse Model of Oral Squamous Cell Carcinoma

Loco-regional invasion of head and neck cancer is linked to metastatic risk and presents a difficult challenge in designing and implementing patient management strategies. Orthotopic mouse models of oral cancer have been developed to facilitate the study of factors that impact invasion and serve as model system for evaluating anti-tumor therapeutics. In these systems, visualization of disseminated tumor cells within oral cavity tissues has typically been conducted by either conventional histology or with in vivo bioluminescent methods. A primary drawback of these techniques is the inherent inability to accurately visualize and quantify early tumor cell invasion arising from the primary site in three dimensions. Here we describe a protocol that combines an established model for squamous cell carcinoma of the tongue (SCOT) with two-photon imaging to allow multi-vectorial visualization of lingual tumor spread. The OSC-19 head and neck tumor cell line was stably engineered to express the F-actin binding peptide LifeAct fused to the mCherry fluorescent protein (LifeAct-mCherry). Fox1nu/nu mice injected with these cells reliably form tumors that allow the tongue to be visualized by ex-vivo application of two-photon microscopy. This technique allows for the orthotopic visualization of the tumor mass and locally invading cells in excised tongues without disruption of the regional tumor microenvironment. In addition, this system allows for the quantification of tumor cell invasion by calculating distances that invaded cells move from the primary tumor site. Overall this procedure provides an enhanced model system for analyzing factors that contribute to SCOT invasion and therapeutic treatments tailored to prevent local invasion and distant metastatic spread. This method also has the potential to be ultimately combined with other imaging modalities in an in vivo setting.

A comprehensive overview of the techniques involved in generating a mouse model of oral cancer and quantitative monitoring of tumor invasion within the tongue through multi-photon microscopy of labeled cells is presented. This system can serve as a useful platform for the molecular assessment and drug efficacy of anti-invasive compounds.

Multi-fotão imagem de invasão das células tumorais em um modelo de camundongo ortotópico de carcinoma epidermóide oral

Loco-regional invasion of head and neck cancer is linked to metastatic risk and presents a difficult challenge in designing and implementing patient ...

Multi-modal Imaging of Angiogenesis in a Nude Rat Model of Breast Cancer Bone Metastasis Using Magnetic Resonance Imaging, Volumetric Computed Tomography and Ultrasound

Angiogenesis is an essential feature of cancer growth and metastasis formation. In bone metastasis, angiogenic factors are pivotal for tumor cell proliferation in the bone marrow cavity as well as for interaction of tumor and bone cells resulting in local bone destruction. Our aim was to develop a model of experimental bone metastasis that allows in vivo assessment of angiogenesis in skeletal lesions using non-invasive imaging techniques.
For this purpose, we injected 105 MDA-MB-231 human breast cancer cells into the superficial epigastric artery, which precludes the growth of metastases in body areas other than the respective hind leg1. Following 25-30 days after tumor cell inoculation, site-specific bone metastases develop, restricted to the distal femur, proximal tibia and proximal fibula1. Morphological and functional aspects of angiogenesis can be investigated longitudinally in bone metastases using magnetic resonance imaging (MRI), volumetric computed tomography (VCT) and ultrasound (US).
MRI displays morphologic information on the soft tissue part of bone metastases that is initially confined to the bone marrow cavity and subsequently exceeds cortical bone while progressing. Using dynamic contrast-enhanced MRI (DCE-MRI) functional data including regional blood volume, perfusion and vessel permeability can be obtained and quantified2-4. Bone destruction is captured in high resolution using morphological VCT imaging. Complementary to MRI findings, osteolytic lesions can be located adjacent to sites of intramedullary tumor growth. After contrast agent application, VCT angiography reveals the macrovessel architecture in bone metastases in high resolution, and DCE-VCT enables insight in the microcirculation of these lesions5,6. US is applicable to assess morphological and functional features from skeletal lesions due to local osteolysis of cortical bone. Using B-mode and Doppler techniques, structure and perfusion of the soft tissue metastases can be evaluated, respectively. DCE-US allows for real-time imaging of vascularization in bone metastases after injection of microbubbles7.
In conclusion, in a model of site-specific breast cancer bone metastases multi-modal imaging techniques including MRI, VCT and US offer complementary information on morphology and functional parameters of angiogenesis in these skeletal lesions.

In the pathogenesis of bone metastasis, angiogenesis is a crucial process and therefore represents a target for imaging and therapy. Here, we present a rat model of site-specific breast cancer bone metastasis and describe strategies to non-invasively image angiogenesis in vivo using magnetic resonance imaging, volumetric computed tomography and ultrasound.

Multi-modal de imagem de angiogênese em um modelo de rato nu de Câncer de mama utilizando a ressonância magnética, tomografia computadorizada volumétrica e ultra-som

Angiogenesis is an essential feature of cancer growth and metastasis formation. In bone metastasis, angiogenic factors are pivotal for tumor cell ...

Screening for Melanoma Modifiers using a Zebrafish Autochthonous Tumor Model

Genomic studies of human cancers have yielded a wealth of information about genes that are altered in tumors1,2,3. A challenge arising from these studies is that many genes are altered, and it can be difficult to distinguish genetic alterations that drove tumorigenesis from that those arose incidentally during transformation. To draw this distinction it is beneficial to have an assay that can quantitatively measure the effect of an altered gene on tumor initiation and other processes that enable tumors to persist and disseminate. Here we present a rapid means to screen large numbers of candidate melanoma modifiers in zebrafish using an autochthonous tumor model4 that encompasses steps required for melanoma initiation and maintenance. A key reagent in this assay is the miniCoopR vector, which couples a wild-type copy of the mitfa melanocyte specification factor to a Gateway recombination cassette into which candidate melanoma genes can be recombined5. The miniCoopR vector has a mitfa rescuing minigene which contains the promoter, open reading frame and 3'-untranslated region of the wild-type mitfa gene. It allows us to make constructs using full-length open reading frames of candidate melanoma modifiers. These individual clones can then be injected into single cell Tg(mitfa:BRAFV600E);p53(lf);mitfa(lf)zebrafish embryos. The miniCoopR vector gets integrated by Tol2-mediated transgenesis6 and rescues melanocytes. Because they are physically coupled to the mitfa rescuing minigene, candidate genes are expressed in rescued melanocytes, some of which will transform and develop into tumors. The effect of a candidate gene on melanoma initiation and melanoma cell properties can be measured using melanoma-free survival curves, invasion assays, antibody staining and transplantation assays.

A rapid way to screen for melanoma modifiers using a zebrafish autochthonous tumor model is presented. It takes advantage of the miniCoopR vector which allows for expression of candidate melanoma genes in melanocytes. A method to obtain melanoma-free survival curves, an invasion assay, a protocol for antibody staining of scale melanocytes and a melanoma transplantation assay are described.

Triagem para Modificadores Melanoma usando um modelo de tumor Zebrafish autóctone

Genomic studies of  human cancers have yielded a wealth of information about genes that are altered  in tumors1,2,3. A challenge arising from these ...

Using Quantitative Real-time PCR to Determine Donor Cell Engraftment in a Competitive Murine Bone Marrow Transplantation Model

Murine bone marrow transplantation models provide an important tool in measuring hematopoietic stem cell (HSC) functions and determining genes/molecules that regulate HSCs. In these transplant model systems, the function of HSCs is determined by the ability of these cells to engraft and reconstitute lethally irradiated recipient mice. Commonly, the donor cell contribution/engraftment is measured by antibodies to donor- specific cell surface proteins using flow cytometry. However, this method heavily depends on the specificity and the ability of the cell surface marker to differentiate donor-derived cells from recipient-originated cells, which may not be available for all mouse strains. Considering the various backgrounds of genetically modified mouse strains in the market, this cell surface/ flow cytometry-based method has significant limitations especially in mouse strains that lack well-defined surface markers to separate donor cells from congenic recipient cells. Here, we reported a PCR-based technique to determine donor cell engraftment/contribution in transplant recipient mice. We transplanted male donor bone marrow HSCs to lethally irradiated congenic female mice. Peripheral blood samples were collected at different time points post transplantation. Bone marrow samples were obtained at the end of the experiments. Genomic DNA was isolated and the Y chromosome specific gene, Zfy1, was amplified using quantitative Real time PCR. The engraftment of male donor-derived cells in the female recipient mice was calculated against standard curve with known percentage of male vs. female DNAs. Bcl2 was used as a reference gene to normalize the total DNA amount. Our data suggested that this approach reliably determines donor cell engraftment and provides a useful, yet simple method in measuring hematopoietic cell reconstitution in murine bone marrow transplantation models. Our method can be routinely performed in most laboratories because no costly equipment such as flow cytometry is required.

Determining donor cell engraftment presents a challenge in mouse bone marrow transplant models that lack well-defined phenotypical markers. We described a methodology to quantify male donor cell engraftment in female transplant recipient mice. This method can be used in all mouse strains for the study of HSC functions.

Usando Quantitative PCR em tempo real para determinar enxerto célula dadora num modelo murino de osso Competitiva Marrow Transplantation

Murine bone marrow transplantation models provide an important tool in measuring hematopoietic stem cell (HSC) functions and determining genes/molecules ...

Excitotoxic Stimulation of Brain Microslices as an In vitro Model of Stroke

Examining molecular mechanisms involved in neuropathological conditions, such as ischemic stroke, can be difficult when using whole animal systems. As such, primary or &#39;neuronal-like&#39; cell culture systems are commonly utilized. While&#160;these systems are relatively easy to work with, and are useful model systems in which various functional outcomes (such as cell death) can be readily quantified, the examined outcomes and pathways in cultured immature neurons (such as excitotoxicity-mediated cell death pathways) are not necessarily the same as those observed in mature brain, or in intact tissue. Therefore, there is the need to develop models in which cellular mechanisms in mature neural tissue can be examined. We have developed an in vitro technique that can be used to investigate a variety of molecular pathways in intact nervous tissue. The technique described herein utilizes rat cortical tissue, but this technique can be adapted to use tissue from a variety of species (such as mouse, rabbit, guinea pig, and chicken) or brain regions (for example, hippocampus, striatum, etc.). Additionally, a variety of stimulations/treatments can be used (for example, excitotoxic, administration of inhibitors, etc.). In conclusion, the brain slice model described herein can be used to examine a variety of molecular mechanisms involved in excitotoxicity-mediated brain injury.

Excitotoxic Stimulation of Brain Microslices as an In vitro Model of Stroke

We have developed a brain slice model which can be used to examine molecular mechanisms involved in excitotoxicity-mediated brain injury.&#160;This technique generates viable mature brain tissue and reduces animal numbers required for experimentation, whilst keeping the neuronal circuitry, cellular interactions, and postsynaptic compartments partly intact.

Excitotóxico Estimulação do Microslices cérebro como um<em&gt; In vitro</em&gt; Modelo de AVC

Examining molecular mechanisms involved in neuropathological conditions, such as ischemic stroke, can be difficult when using whole animal systems. As ...

Femoral Bone Marrow Aspiration in Live Mice

Serial sampling of the cellular composition of bone marrow (BM) is a routine procedure critical to clinical hematology. This protocol describes a detailed step-by-step technical procedure for an analogous procedure in live mice which allows for serial characterization of cells present in the BM. This procedure facilitates studies aimed to detect the presence of exogenously administered cells within the BM of mice as would be done in xenograft studies for instance. Moreover, this procedure allows for the retrieval and characterization of cells enriched in the BM such as hematopoietic stem and progenitor cells (HSPCs) without sacrifice of mice. Given that the cellular composition of peripheral blood is not necessarily reflective of proportions and types of stem and progenitor cells present in the marrow, procedures which provide access to this compartment without requiring termination of the mice are very helpful. The use of femoral bone marrow aspiration is illustrated here for cytological analysis of marrow cells, flow cytometric characterization of the hematopoietic stem/progenitor compartment, and culture of sorted HSPCs obtained by femoral BM aspiration compared with conventional marrow harvest.

This protocol describes a procedure for serial sampling of femoral bone marrow (BM) without requiring the sacrifice of mice. This procedure facilitates longitudinal studies of the BM composition of mice over time and provides serial access to cells within the BM for ex vivo and transplantation studies.

Femoral Medula Óssea aspiração Live Ratos

Serial sampling of the cellular composition of bone marrow (BM) is a routine procedure critical to clinical hematology. This protocol describes a detailed ...

An Ex vivo Model to Study Hormone Action in the Human Breast

The study of hormone action in the human breast has been hampered by lack of adequate model systems. Upon in vitro culture, primary mammary epithelial cells tend to lose hormone receptor expression. Widely used hormone receptor positive breast cancer cell lines are of limited relevance to the in vivo situation. Here, we describe an ex vivo model to study hormone action in the human breast. Fresh human breast tissue specimens from surgical discard material such as reduction mammoplasties or mammectomies are mechanically and enzymatically digested to obtain tissue fragments containing ducts and lobules and multiple stromal cell types. These tissue microstructures kept in basal medium without growth factors preserve their intercellular contacts, the tissue architecture, and remain hormone responsive for several days. They are readily processed for RNA and protein extraction, histological analysis or stored in freezing medium. Fluorescence activated cell sorting (FACS) can be used to enrich for specific cell populations. This protocol provides a straightforward, standard approach for translational studies with highly complex, varied human specimens.

An Ex vivo Model to Study Hormone Action in the Human Breast

We have developed a novel ex vivo model to study hormone action in the human breast. It is based on tissue microstructures isolated from surgical breast tissue specimens which preserve tissue architecture, intercellular interactions, and paracrine signaling.

Um<em&gt; Ex vivo</em&gt; Modelo para estudar a ação do hormônio no peito humano

The study of hormone action in the human breast has been hampered by lack of adequate model systems. Upon in vitro culture, primary mammary epithelial ...

In Vivo and Ex Vivo Approaches to Study Ovarian Cancer Metastatic Colonization of Milky Spot Structures in Peritoneal Adipose

High-grade serous ovarian cancer (HGSC), the cause of widespread peritoneal metastases, continues to have an extremely poor prognosis; fewer than 30% of women are alive 5 years after diagnosis. The omentum is a preferred site of HGSC metastasis formation. Despite the clinical importance of this microenvironment, the contribution of omental adipose tissue to ovarian cancer progression remains understudied. Omental adipose is unusual in that it contains structures known as milky spots, which are comprised of B, T, and NK cells, macrophages, and progenitor cells surrounding dense nests of vasculature. Milky spots play a key role in the physiologic functions of the omentum, which are required for peritoneal homeostasis. We have shown that milky spots also promote ovarian cancer metastatic colonization of peritoneal adipose, a key step in the development of peritoneal metastases. Here we describe the approaches we developed to evaluate and quantify milky spots in peritoneal adipose and study their functional contribution to ovarian cancer cell metastatic colonization of omental tissues both in vivo and ex vivo. These approaches are generalizable to additional mouse models and cell lines, thus enabling the study of ovarian cancer metastasis formation from initial localization of cells to milky spot structures to the development of widespread peritoneal metastases.

In Vivo and Ex Vivo Approaches to Study Ovarian Cancer Metastatic Colonization of Milky Spot Structures in Peritoneal Adipose

We outline a protocol that implements both in vivo and ex vivo approaches to study ovarian cancer colonization of peritoneal adipose tissues, particularly the omentum. Furthermore, we present a protocol to quantitate and analyze immune cell-structures in the omentum known as milky spots, which promote metastases of peritoneal adipose.

In Vivo e Ex Vivo Abordagens para o Estudo do cancro do ovário metastático Colonização de Estruturas Láctea natural em Peritoneal adiposo

High-grade serous ovarian cancer (HGSC), the cause of widespread peritoneal metastases, continues to have an extremely poor prognosis; fewer than 30% of ...

Utilization of the Soft Agar Colony Formation Assay to Identify Inhibitors of Tumorigenicity in Breast Cancer Cells

Given the inherent difficulties in investigating the mechanisms of tumor progression in vivo, cell-based assays such as the soft agar colony formation assay (hereafter called soft agar assay), which measures the ability of cells to proliferate in semi-solid matrices, remain a hallmark of cancer research. A key advantage of this technique over conventional 2D monolayer or 3D spheroid cell culture assays is the close mimicry of the 3D cellular environment to that seen in vivo. Importantly, the soft agar assay also provides an ideal tool to rigorously test the effects of novel compounds or treatment conditions on cell proliferation and migration. Additionally, this assay enables the quantitative assessment of cell transformation potential within the context of genetic perturbations. We recently identified peptidylarginine deiminase 2 (PADI2) as a potential breast cancer biomarker and therapeutic target. Here we highlight the utility of the soft agar assay for preclinical anti-cancer studies by testing the effects of the PADI inhibitor, BB-Cl-amidine (BB-CLA), on the tumorigenicity of human ductal carcinoma in situ (MCF10DCIS) cells.

Here, we document the use of the soft agar colony formation assay to test the effects of a peptidylarginine deiminase (PADI) enzyme inhibitor, BB-Cl-amidine, on breast cancer tumorigenicity in vitro.

Utilização do ensaio de formação de colónia agar mole para identificar inibidores de tumorigenicidade em células de cancro da mama

Given the inherent difficulties in investigating the mechanisms of tumor progression in vivo, cell-based assays such as the soft agar colony formation ...