Este trabalho é apoiado pela BRC imperial, o Instituto Nacional de Pesquisa em Saúde e Acção contra o Cancro, com menção especial para Hilary Craft e Sir Douglas Myers.

Os procedimentos a seguir foram eticamente aprovado pelo Imperial College, de Londres. 1. Geração de primárias Mammospheres de linhas celulares de cancro da mama humano NOTA: Execute as seguintes etapas sob uma capa de cultura estéril. <ol><li> Prepare Mammosphere meios contendo DMEM / F12 suplementado com 2 mM de L-glutamina, 100 U / ml de penicilina, 100 U / ml de estreptomicina. Prepare media completo imediatamente antes da utilização, adicionando 20 fator ng / ml recombinante de crescimento epidérmico humano (EGF; Sigma), 10 ng / ml fator recombinante humano básico de crescimento de fibroblastos (bFGF; Sistemas I &amp; D) e suplemento 1x B27. </li><li> Aspirar meios de balão contendo aderentes MCF-7 ou MDA-MB-231 (ou uma linha celular de cancro da mama de sua escolha; 70-80% de confluência), lavar duas vezes em 1x PBS, e trypsinize células. </li><li> Centrifugar células a 200 xg à temperatura ambiente durante 5 min. Células sobrenadante e ressuspender Decantar em 1-5 ml de mídia mammosphere. Pipetacima e para baixo e, se necessário, use um 40 um filtro cap filtro de células para obter a suspensão de uma única célula. Usar um hemocitómetro para assegurar uma suspensão de célula única formou (se não, usar uma agulha G 25, a seringa da suspensão de células até 3 vezes). </li><li> Se necessário isolar CD44 + CD24- subconjunto celular através de FACS utilizando anticorpos anti-CD24-ficoeritrina (PE) e isotiocianato (FITC) anticorpos monoclonais anti-9-CD44 fluoresceína. Alternativamente, isolar tais população que utiliza uma célula magnética ativado triagem do sistema (MACS) com anti-CD44 e microbeads combinados-anti-CD24 biotina, conforme as instruções do fabricante. Realizar seleção positiva usando LS colunas e seleção negativa usando colunas LD e confirmar os fenótipos de todas as células isoladas por citometria de fluxo 17. </li><li> Calcula-se o número de células viáveis ​​por ml, utilizando azul de tripano. NOTA: A viabilidade das células é calculada como o número de células viáveis, dividido pelo número total de células dentro das grades na hemocytometer. As células que ocupam azul tripan são considerados inviáveis. O procedimento seguinte é utilizado para determinar com precisão a percentagem de células viáveis. <ol><li> Prepara-se uma solução 0,4% de azul de tripano em PBS. Adicionar 0,1 ml de solução de estoque de azul de tripano a 1 ml de células. Coloque um hemocitômetro e examinar imediatamente sob um microscópio com pequeno aumento. Contar o número de células totais e o número de células coradas de azul. As células viáveis ​​= [1,00 - (número de células azuis ÷ Número de células totais)] x 100. </li><li> Para calcular o número de células viáveis ​​por ml de cultura, utilize a fórmula abaixo. Lembre-se de corrigir o fator de diluição. Número de células viáveis ​​× 10 × 1,1 = 4 células / ml de cultura </li></ol></li><li> Ressuspender uma quantidade pré-determinada de células em 2 ml de meio mammosphere completos em cada poço de uma placa de 6 poços aderente ultra-baixo. A densidade de sementeira é normalmente 500-4,000 células / cm2 de células por poço. Utilização lo Opcionalmentefixação w placas de 24 poços enquanto sementeira de células com a mesma densidade em 0,5 ml de meio. NOTA: Recomendamos a otimização da densidade de semeadura e tempo de cultivo para cada linhas de células de interesse. </li><li> Incubar baixa de fixação 6-se placas de ultra a 37 ° C e 5% de CO 2 durante 5-10 dias (dependendo da linha de células e o tamanho do mammospheres) sem perturbar as placas, particularmente durante a fase de crescimento dos primeiros 5 dias . </li></ol> 2. Geração de primárias Mammospheres de cancro da mama humano amostras clínicas NOTA: tecido de cancro da mama humano pode ser obtido a partir de doentes submetidos a cirurgia para a remoção de tumores da mama. Tecido da loja em gelo durante até 24 horas em tubos de 50 ml estéreis em meio de cultura contendo 100 U / ml de penicilina e 100 U / ml de estreptomicina. Execute as seguintes etapas em uma capa de cultura estéril. <ol><li> Transfira a amostra num tecido 100 milímetros placa de Petri com um pequeno volume de meio. REMOVe do tecido adiposo com tesoura estéril, scapel e pinças. </li><li> Adicionar 2-3 ml de DMEM / F12 e pique a amostra em 1 milímetro 3 peças com um scapel estéril ou lâmina de barbear até que não haja grandes pedaços permanecem. </li><li> Ressuspender as peças de tecido em pré-aquecida de 10 ml de DMEM contendo enzimas proteolíticas (3.000 U / ml de colagenase e 1.000 U / ml de hialuronidase) e incubar a 37 ° C num agitador rotativo até que todos os fragmentos de tecido são digeridos. Normalmente, a digestão completa leva 1-3 horas. Ajuste o tempo de digestão de acordo com caracteres patológicos de tumores. (Por exemplo adenocarcinoma de mama é geralmente mais difícil de digerir em comparação com carcinoma mucinoso que é mais frágil e necessita de menor tempo de digestão). Avaliar o grau de digestão cada hora ½ observando 20 suspensão ul sob hemocitômetro. </li><li> Permitir que os fragmentos a sedimentar durante 5 min, em seguida, transferir o sobrenadante num tubo de polipropileno cónico de 15 ml e centrifugar a 200 xg durante 10 min a ma quartoratura. Decantar cuidadosamente as células sobrenadante e ressuspender em 1-5 ml de mídia mammosphere. </li><li> Siga os passos descritos acima para 1,1-1,4 linhas celulares para obter e chapa suspensões de células individuais. Passe células através da seringa 25 G um máximo de 2 vezes, se necessário limitar células prejudiciais. </li></ol> 3. Mammosphere Formando Eficiência (%) Cálculo <ol><li> Após o período de cultura, contar os mammospheres (maior do que 40 um) de diâmetro sob um microscópio com uma ampliação de 40X. Imagem digital 5 campos aleatórios utilizando uma câmera digital em um microscópio de luz e determinar o tamanho mammospheres usando o software de aquisição. Usar qualquer imagem Software Analysis. </li><li> Calcule Mammosphere Eficiência Formando (MFE%) utilizando a seguinte equação: MFE (%) = (# de mammospheres por poço) / (# de células semeadas por poço) x 100 </li></ol> 4. Passaging Serial de Mammospheres de Avaliação da auto-renovação <ol><li&gt; Pipeta o meio contendo as mammospheres de cada poço para um tubo de 15 ml. Lavar os poços com PBS e adicionar aos media recolhidos. Centrifugar a 115 xg durante 10 min à temperatura ambiente. </li><li> Descartar o sobrenadante e ressuspender o sedimento em 500 ul de pré-aquecido 0,5% de tripsina / EDTA a 0,2%. Incubar por 2-3 min. </li><li> Adicionar 500 ul de FCS para neutralizar a tripsina. Centrifugar a 500 xg durante 5 min. Elimine o sobrenadante e ressuspender sedimento em 100 mL de mídia mammospheres, pipetagem cima e para baixo para desagregar esferas. </li><li> Contar as células com um hemocitómetro e determinar se as células estão em suspensão de célula única. Se não passar através de uma seringa 25 G até 3 vezes para se obter células isoladas. Semente as células em um novo ultra-baixo apego 6 bem-placa com a mesma densidade utilizado na geração primária. </li><li> Depois de 5-10 dias, conte esferas&gt; 40 mm e calcular a eficiência de formação de esfera usando a fórmula relatada antes. </li></ol>

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The authors declare that there is no conflict of interest that could be perceived as prejudicing the impartiality of this article.

Avaliação positiva dos mammospheres primárias e secundárias depende das células sendo banhado pelo suficientemente baixas densidades que mammospheres formulário a partir de clones de solteiro, com esfera de agregação mínima. No entanto em densidades que são muito baixos, muito poucos mammospheres podem formar para distinguir os efeitos de tratamentos estatisticamente. Densidade de semeadura deve ser otimizado para cada linha celular utilizada, uma vez que podem variar consideravelmente em suas eficiências esf...

A existência de linhagens de células tumorais chefiadas por células-tronco cancerosas-tronco como contribuiu largamente para a nossa compreensão da heterogeneidade tumor. Enquanto alguns diversidade fenotípica em tumores que surgem do crescimento clonal de clones geneticamente distintas, um componente substancial parece resultar de diferenças epigenéticas: as células cancerosas podem fazer a transição (por vezes de forma reversível) entre a haste, progenitor, e os estados diferenciados através da ativação ou repressão do gene específico programas de expressão 1-3. Isto pode reflectir factores intrínsecos ou extrínsecos de células, reflectindo a expressão do gene programa actualmente a ser expresso em uma célula com a sua sinalização a autócrino resultante em conjunto com sinalização parácrina da vizinha cancro, estromais ou células imunitárias entregar factores moduladores, e microenviromental condições tais como o grau de hipóxia 2,4,5. Embora as abordagens rastreamento de linhagem inovadorasestão avançando a nossa capacidade de estudar as células-tronco do câncer putativos em sua in vivo nicho 6-8, ensaios de formação de esfera continuará a ser uma abordagem popular e conveniente para estimar o potencial de células de câncer de mama &quot;para se comportar como células-tronco, pelo menos nas condições de ensaio utilizados. É frequentemente utilizado juntamente com os métodos retrospectivos para cancro de células estaminais de purificação, pela sua expressão de marcadores de membrana CD44 e CD24 9, e os níveis de enzima ALDH (aldeído desidrogenase) de actividade 10, marcadores que têm sido propostos para corresponder a mais mesenchymal- e epitelial -como células-tronco do câncer, respectivamente 11. A abordagem formação esfera foi desenvolvido pela primeira vez como o ensaio de neuroesferas, permitindo o crescimento de células estaminais putativas a partir de clones individuais em não-aderentes, condições livres de soro, com a adição de factor de crescimento epitelial (EGF) 12, sendo posteriormente aplicado utilmente ao normal e canceroso tecidos mamários. <p class = &quot;jove_content&quot;&gt; A identidade da célula fundadora formador de esfera, e os tipos de células mistas que constituem a massa esfera, são relevantes para as deduções que podem ser feitos a partir de mammo-, ou outra esfera formando-ensaios. Células-tronco a longo prazo ósseas repouso fide, pensado para descansar em fase G0, não vai experimentar a combinação precisa de fatores que favorecem a ativação in vivo. O ensaio mammosphere vez permite o crescimento de células ou pronta para divisão mitótica ou já divisórias 13. Estes progenitores, embora não uma célula verdadeiramente quiescente, pode ser a célula que prolifera fase com os agentes mitogénicos de EGF e factor de crescimento de fibroblastos básico (bFGF) utilizados no ensaio. No entanto, eles contêm uma variedade de haste ativado sinalização associado a células vias 14. Além disso, a taxa da sua formação está relacionada com a tumorigenicidade de tecido que foram retiradas, quando medido pela sua potência para ensaios de diluição limitadas em xenoenxertos de ratinho 2,15,16 &lt;/ Sup&gt;. Aqui nós fornecemos protocolos detalhados para isolar células individuais e que geram mammospheres primárias de ambas as linhas de células de câncer de mama humano e amostras clínicas de tumores de mama. Nós também descrevem como executar passagens em série de mammospheres primários para avaliar a auto-renovação, e como calcular esfera formando eficiência que permite a comparação entre diferentes densidades de semeadura (ver esquema na figura 1).

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			<td height="21" style="height:21px;width:625px;">Name of Material/ Equipment</td>
			<td style="width:139px;">Company</td>
			<td style="width:119px;">Catalog Number</td>
			<td style="width:167px;">Comments/Description</td>
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			<td height="21" style="height:21px;">DMEM/F12</td>
			<td style="width:139px;">Lonza</td>
			<td>CC-3151</td>
			<td></td>
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		<tr height="25">
			<td height="25" style="height:25px;width:625px;">2mM L-Glutamine</td>
			<td style="width:139px;">Sigma Aldrich</td>
			<td>G8540</td>
			<td></td>
		</tr>
		<tr height="27">
			<td height="27" style="height:27px;width:625px;">100U/ml Penicillin &#38; Streptomycin</td>
			<td style="width:139px;">Sigma Aldrich</td>
			<td>P4083</td>
			<td></td>
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		<tr height="25">
			<td height="25" style="height:25px;width:625px;">20ng/ml recombinant human epidermal growth factor (EGF)</td>
			<td style="width:139px;">Sigma Aldrich</td>
			<td>E9644</td>
			<td></td>
		</tr>
		<tr height="22">
			<td height="22" style="height:22px;width:625px;">20ng/ml recombinant human basic fibroblast growth factor (bFGF)</td>
			<td style="width:139px;">R&#38;D systems</td>
			<td>233-FB-025</td>
			<td></td>
		</tr>
		<tr height="22">
			<td height="22" style="height:22px;width:625px;">1x B27 supplement&#160;</td>
			<td style="width:139px;">Invitrogen</td>
			<td>17504-044</td>
			<td></td>
		</tr>
		<tr height="27">
			<td height="27" style="height:27px;">Phosphate buffered saline (PBS);</td>
			<td style="width:139px;">Thermo Scientific</td>
			<td>12399902</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">&#160;0.5% trypsin-0.2%EDTA;</td>
			<td style="width:139px;">Sigma Aldrich</td>
			<td>59418C</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Fetal Calf Serum</td>
			<td style="width:139px;">First Link UK</td>
			<td>02-00-850</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">&#160;Trypan Blue</td>
			<td style="width:139px;">Sigma Aldrich</td>
			<td>93595</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">&#160;Low attachment 6 well plates</td>
			<td style="width:139px;">Corning</td>
			<td>CLS3814</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Collagenase type 1A</td>
			<td style="width:139px;">Sigma Aldrich</td>
			<td>C9891</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Hyaluronidase</td>
			<td style="width:139px;">Sigma Aldrich</td>
			<td>H3506</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Sterile razor blades</td>
			<td style="width:139px;">Fisher Scientific</td>
			<td>12443170</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:625px;">Sterile scalpel</td>
			<td style="width:139px;">Fisher Scientific</td>
			<td style="width:119px;">11758353</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:625px;">Sterile micro-dissecting scissors</td>
			<td style="width:139px;">Sigma Aldrich</td>
			<td>S3146</td>
			<td></td>
		</tr>
	</tbody>
</table>

mammosphere formation assay from human breast cancer tissues and cell lines

Similar aos tecidos saudáveis, muitas sangue e tumores sólidos são pensados ​​agora para ser organizados hierarquicamente, com um subconjunto de células-tronco cancerosas, como que se auto-renovar, dando origem a descendência mais diferenciada. Compreensão e segmentação destas células-tronco cancerosas no câncer de mama, que pode possuir reforçada quimio e radio-resistência em comparação com o volume do tumor não-haste, tornou-se uma importante área de pesquisa. Os marcadores, incluindo CD44, CD24, e a actividade de ALDH pode ser avaliada utilizando células activadas por fluorescência (FACS) para prospectivamente isolar células que exibem tumorigenicidade aumentada quando implantadas em ratinhos imunocomprometidos: o ensaio mammosphere também tem sido amplamente usada para a sua capacidade para identificar retrospectivamente sphere- formação de células que se desenvolvem a partir de clones de células-tronco como single. Aqui destacamos abordagens para a cultura apropriada de mammospheres de linhas celulares ou amostras primárias do paciente, sua passaging e cálculos para estimar esfera feficiência orming (SFE). Primeiro vamos discutir as principais considerações e armadilhas no planejamento e interpretação de experimentos mammosphere apropriado.

Diferentes amostras ou os sujeitos a diferentes tratamentos podem variar no número de mammospheres&gt; 40 mm que se formam após a normalização para células iniciais semeadas. Calcular mammosphere formando eficiência (MFE) para cada tratamento cultivadas em triplicado. Isto permite que as experiências com diferentes densidades de semeadura para ser comparadas. Os dados são melhor apresentado em um gráfico de barras, de preferência, com os controlos positivos e negativos, e mostrar o desvio padrão entre as cavi...

Watch this Scientific Journal Video about Mammosphere Formation Assay from Human Breast Cancer Tissues and Cell Lines at JoVE.com

Mammosphere Formation Assay from Human Breast Cancer Tissues and Cell Lines

Floating mammosphere assays can investigate the subset of stem-like breast cancer cells that survive in suspension conditions and show enhanced tumorigenesis when implanted into mice. This protocol provides a convenient in vitro measure of sphere-forming ability, a proxy for in vivo tumorigenesis, while facilitating analysis of the stem-associated transcriptional landscape.

Formação Mammosphere Ensaio de cancro da mama humano tecidos e linhas celulares

Similar to healthy tissues, many blood and solid malignancies are now thought to be organised hierarchically, with a subset of stem-like cancer cells that ...

mammosphere-formation-assay-from-human-breast-cancer-tissues-cell

Research

JoVE Journal

Medicine

33.0K visualizações.  Imperial College London. Floating mammosphere assays can investigate the subset of stem-like breast cancer cells that survive in suspension conditions and show enhanced tumorigenesis when implanted into mice. This protocol provides a convenient in vitro measure of sphere-forming ability, a proxy for in vivo tumorigenesis, while facilitating analysis of the stem-associated transcriptional landscape.

Vídeo: Mammosphere Formation Assay from Human Breast Cancer Tissues and Cell Lines

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 ...

Medicina

Processing of Human Reduction Mammoplasty and Mastectomy Tissues for Cell Culture

Experimental examination of normal human mammary epithelial cell (HMEC) behavior, and how normal cells acquire abnormal properties, can be facilitated by in vitro culture systems that more accurately model in vivo biology. The use of human derived material for studying cellular differentiation, aging, senescence, and immortalization is particularly advantageous given the many significant molecular differences in these properties between human and commonly utilized rodent cells1-2. Mammary cells present a convenient model system because large quantities of normal and abnormal tissues are available due to the frequency of reduction mammoplasty and mastectomy surgeries.
The mammary gland consists of a complex admixture of many distinct cell types, e.g., epithelial, adipose, mesenchymal, endothelial. The epithelial cells are responsible for the differentiated mammary function of lactation, and are also the origin of the vast majority of human breast cancers. We have developed methods to process mammary gland surgical discard tissues into pure epithelial components as well as mesenchymal cells3. The processed material can be stored frozen indefinitely, or initiated into primary culture. Surgical discard material is transported to the laboratory and manually dissected to enrich for epithelial containing tissue. Subsequent digestion of the dissected tissue using collagenase and hyaluronidase strips stromal material from the epithelia at the basement membrane. The resulting small pieces of the epithelial tree (organoids) can be separated from the digested stroma by sequential filtration on membranes of fixed pore size. Depending upon pore size, fractions can be obtained consisting of larger ductal/alveolar pieces, smaller alveolar clusters, or stromal cells. We have observed superior growth when cultures are initiated as organoids rather than as dissociated single cells. Placement of organoids in culture using low-stress inducing media supports long-term growth of normal HMEC with markers of multiple lineage types (myoepithelial, luminal, progenitor)4-5. Sufficient numbers of cells can be obtained from one individual's tissue to allow extensive experimental examination using standardized cell batches, as well as interrogation using high throughput modalities.
Cultured HMEC have been employed in a wide variety of studies examining the normal processes governing growth, differentiation, aging, and senescence, and how these normal processes are altered during immortal and malignant transformation4-15,16. The effects of growth in the presence of extracellular matrix material, other cell types, and/or 3D culture can be compared with growth on plastic5,15. Cultured HMEC, starting with normal cells, provide an experimentally tractable system to examine factors that may propel or prevent human aging and carcinogenesis.

A method to process human mammary surgical discard material is described. Processed tissue, in the form of organoids, can be stored frozen indefinitely or placed in culture for long-term growth. This method enables experimental examination of normal human epithelial cell biology, and the effects of exogenous perturbations.

Processamento da mamoplastia redutora e tecidos humanos Mastectomia para cultura de células

Experimental  examination of normal human mammary epithelial cell (HMEC) behavior, and how  normal cells acquire abnormal properties, can be facilitated ...

Time-lapse Imaging of Primary Preneoplastic Mammary Epithelial Cells Derived from Genetically Engineered Mouse Models of Breast Cancer

Time-lapse imaging can be used to compare behavior of cultured primary preneoplastic mammary epithelial cells derived from different genetically engineered mouse models of breast cancer. For example, time between cell divisions (cell lifetimes), apoptotic cell numbers, evolution of morphological changes, and mechanism of colony formation can be quantified and compared in cells carrying specific genetic lesions. Primary mammary epithelial cell cultures are generated from mammary glands without palpable tumor. Glands are carefully resected with clear separation from adjacent muscle, lymph nodes are removed, and single-cell suspensions of enriched mammary epithelial cells are generated by mincing mammary tissue followed by enzymatic dissociation and filtration. Single-cell suspensions are plated and placed directly under a microscope within an incubator chamber for live-cell imaging. Sixteen 650 &mu;m x 700 &mu;m fields in a 4x4 configuration from each well of a 6-well plate are imaged every 15 min for 5 days. Time-lapse images are examined directly to measure cellular behaviors that can include mechanism and frequency of cell colony formation within the first 24 hr of plating the cells (aggregation versus cell proliferation), incidence of apoptosis, and phasing of morphological changes. Single-cell tracking is used to generate cell fate maps for measurement of individual cell lifetimes and investigation of cell division patterns. Quantitative data are statistically analyzed to assess for significant differences in behavior correlated with specific genetic lesions.

Time-lapse imaging is used to assess behavior of primary preneoplastic mammary epithelial cells derived from genetically engineered mouse models of breast cancer risk to determine if there are correlations between specific behavioral parameters and distinct genetic lesions.

Lapso de tempo de imagem de pré-neoplásicas primárias células epiteliais mamárias derivados de modelos de rato geneticamente modificado do cancro da mama

Time-lapse  imaging can be used to compare behavior of cultured primary preneoplastic  mammary epithelial cells derived from different genetically ...

The Use of Reverse Phase Protein Arrays (RPPA) to Explore Protein Expression Variation within Individual Renal Cell Cancers

Currently there is no curative treatment for metastatic clear cell renal cell cancer, the commonest variant of the disease. A key factor in this treatment resistance is thought to be the molecular complexity of the disease 1. Targeted therapy such as the tyrosine kinase inhibitor (TKI)-sunitinib have been utilized, but only 40% of patients will respond, with the overwhelming majority of these patients relapsing within 1 year 2. As such the question of intrinsic and acquired resistance in renal cell cancer patients is highly relevant 3.
In order to study resistance to TKIs, with the ultimate goal of developing effective, personalized treatments, sequential tissue after a specific period of targeted therapy is required, an approach which had proved successful in chronic myeloid leukaemia 4. However the application of such a strategy in renal cell carcinoma is complicated by the high level of both inter- and intratumoral heterogeneity, which is a feature of renal cell carcinoma5,6 as well as other solid tumors 7. Intertumoral heterogeneity due to transcriptomic and genetic differences is well established even in patients with similar presentation, stage and grade of tumor. In addition it is clear that there is great morphological (intratumoral) heterogeneity in RCC, which is likely to represent even greater molecular heterogeneity. Detailed mapping and categorization of RCC tumors by combined morphological analysis and Fuhrman grading allows the selection of representative areas for proteomic analysis.
Protein based analysis of RCC8 is attractive due to its widespread availability in pathology laboratories; however, its application can be problematic due to the limited availability of specific antibodies 9. Due to the dot blot nature of the Reverse Phase Protein Arrays (RPPA), antibody specificity must be pre-validated; as such strict quality control of antibodies used is of paramount importance. Despite this limitation the dot blot format does allow assay miniaturization, allowing for the printing of hundreds of samples onto a single nitrocellulose slide. Printed slides can then be analyzed in a similar fashion to Western analysis with the use of target specific primary antibodies and fluorescently labelled secondary antibodies, allowing for multiplexing. Differential protein expression across all the samples on a slide can then be analyzed simultaneously by comparing the relative level of fluorescence in a more cost-effective and high-throughput manner.

The Use of Reverse Phase Protein Arrays RPPA to Explore Protein Expression Variation within Individual Renal Cell Cancers

RPPA enables the protein expression of hundreds of samples, printed on nitrocellulose slides to be interrogated simultaneously, using fluorescently labelled antibodies. This technique has been applied to study the effect of drug treatment heterogeneity within clear cell renal carcinoma.

O uso de matrizes de fase reversa Proteínas (RPPA) para explorar variação Protein Expression individuais dentro de câncer de células renais

Currently there is no curative treatment for metastatic clear cell renal cell cancer, the commonest variant of the disease. A key factor in this treatment ...

Formation of Human Prostate Epithelium Using Tissue Recombination of Rodent Urogenital Sinus Mesenchyme and Human Stem Cells

Progress in prostate cancer research is severely limited by the availability of human-derived and hormone-na&iuml;ve model systems, which limit our ability to understand genetic and molecular events underlying prostate disease initiation. Toward developing better model systems for studying human prostate carcinogenesis, we and others have taken advantage of the unique pro-prostatic inductive potential of embryonic rodent prostate stroma, termed urogenital sinus mesenchyme (UGSM). When recombined with certain pluripotent cell populations such as embryonic stem cells, UGSM induces the formation of normal human prostate epithelia in a testosterone-dependent manner. Such a human model system can be used to investigate and experimentally test the ability of candidate prostate cancer susceptibility genes at an accelerated pace compared to typical rodent transgenic studies. Since Human embryonic stem cells (hESCs) can be genetically modified in culture using inducible gene expression or siRNA knock-down vectors prior to tissue recombination, such a model facilitates testing the functional consequences of genes, or combinations of genes, which are thought to promote or prevent carcinogenesis.
The technique of isolating pure populations of UGSM cells, however, is challenging and learning often requires someone with previous expertise to personally teach. Moreover, inoculation of cell mixtures under the renal capsule of an immunocompromised host can be technically challenging. Here we outline and illustrate proper isolation of UGSM from rodent embryos and renal capsule implantation of tissue mixtures to form human prostate epithelium. Such an approach, at its current stage, requires in vivo xenografting of embryonic stem cells; future applications could potentially include in vitro gland formation or the use of induced pluripotent stem cell populations (iPSCs).

To unravel the earliest molecular mechanisms underlying prostate cancer initiation, novel and innovative human model systems and approaches are desperately needed. The potential of pre-prostatic urogenital sinus mesenchyme (UGSM) to induce pluripotent stem cell populations to form human prostate epithelium is a powerful experimental tool in prostate research.

Formação de Epithelium próstata humano utilizando Tissue Recombinação de Rodent Urogenital Mesênquima Sinus e células-tronco humanas

Progress in prostate cancer research is severely  limited by the availability of human-derived and hormone-na&iuml;ve model systems,  which limit our ...

Profiling of Estrogen-regulated MicroRNAs in Breast Cancer Cells

Estrogen plays vital roles in mammary gland development and breast cancer progression. It mediates its function by binding to and activating the estrogen receptors (ERs), ER&#945;, and ER&#946;. ER&#945; is frequently upregulated in breast cancer and drives the proliferation of breast cancer cells. The ERs function as transcription factors and regulate gene expression. Whereas ER&#945;&#39;s regulation of protein-coding genes is well established, its regulation of noncoding microRNA (miRNA) is less explored. miRNAs play a major role in the post-transcriptional regulation of genes, inhibiting their translation or degrading their mRNA. miRNAs can function as oncogenes or tumor suppressors&#160;and are also promising biomarkers. Among the miRNA assays available, microarray and quantitative real-time polymerase chain reaction (qPCR) have been extensively used to detect and quantify miRNA levels. To identify miRNAs regulated by estrogen signaling in breast cancer, their expression in ER&#945;-positive breast cancer cell lines were compared before and after estrogen-activation using both the &#181;Paraflo-microfluidic microarrays and Dual Labeled Probes-low density arrays. Results were validated using specific qPCR assays, applying both Cyanine dye-based and Dual Labeled Probes-based chemistry. Furthermore, a time-point assay was used to identify regulations over time. Advantages of the miRNA assay approach used in this study is that it enables a fast screening of mature miRNA regulations in numerous samples, even with limited sample amounts. The layout, including the specific conditions for cell culture and estrogen treatment, biological and technical replicates, and large-scale screening followed by in-depth confirmations using separate techniques, ensures a robust detection of miRNA regulations,&#160;and eliminates false positives and other artifacts. However, mutated or unknown miRNAs, or regulations at the primary and precursor transcript level, will not be detected. The method presented here represents a thorough investigation of estrogen-mediated miRNA regulation.

Molecular signaling through both estrogen and microRNAs are critical in breast cancer development and growth. Estrogen activates the estrogen receptors, which are transcription factors. Many transcription factors can regulate the expression of microRNAs, and estrogen-regulated microRNAs can be profiled using different large-scale techniques.

Profiling de MicroRNAs estrogênio regulados em células do cancro da mama

Estrogen plays vital roles in mammary gland development and breast cancer progression. It mediates its function by binding to and activating the estrogen ...

Quantification of Breast Cancer Cell Invasiveness Using a Three-dimensional (3D) Model

It is now well known that the cellular and tissue microenvironment are critical regulators influencing tumor initiation and progression. Moreover, the extracellular matrix (ECM) has been demonstrated to be a critical regulator of cell behavior in culture and homeostasis in vivo. The current approach of culturing cells on two-dimensional (2D), plastic surfaces results in the disturbance and loss of complex interactions between cells and their microenvironment. Through the use of three-dimensional (3D) culture assays, the conditions for cell-microenvironment interaction are established resembling the in vivo microenvironment. This article provides a detailed methodology to grow breast cancer cells in a 3D basement membrane protein matrix, exemplifying the potential of 3D culture in the assessment of cell invasion into the surrounding environment. In addition, we discuss how these 3D assays have the potential to examine the loss of signaling molecules that regulate epithelial morphology by immunostaining procedures. These studies aid to identify important mechanistic details into the processes regulating invasion, required for the spread of breast cancer.

Quantification of Breast Cancer Cell Invasiveness Using a Three-dimensional 3D Model

This article provides detailed methodologies for the use of three-dimensional (3D) assays to quantify breast cancer cell invasion. Specifically, we discuss the procedures required to set up such assays, quantification, and data analysis, as well as methods to examine the loss of membrane integrity that occurs when cells invade.

Quantificação de cancro da mama invasiva das células usando um modelo (3D) tridimensional

It is now well known that the cellular and tissue microenvironment are critical regulators influencing tumor initiation and progression. Moreover, the ...

Enrichment for Chemoresistant Ovarian Cancer Stem Cells from Human Cell Lines

Cancer stem cells (CSCs) are defined as a subset of slow cycling and undifferentiated cells that divide asymmetrically to generate highly proliferative, invasive, and chemoresistant tumor cells. Therefore, CSCs are an attractive population of cells to target therapeutically. CSCs are predicted to contribute to a number of types of malignancies including those in the blood, brain, lung, gastrointestinal tract, prostate, and ovary. Isolating and enriching a tumor cell population for CSCs will enable researchers to study the properties, genetics, and therapeutic response of CSCs. We generated a protocol that reproducibly enriches for ovarian cancer CSCs from ovarian cancer cell lines (SKOV3 and OVCA429). Cell lines are treated with 20 &#181;M cisplatin for 3 days. Surviving cells are isolated and cultured in a serum-free stem cell media containing cytokines and growth factors. We demonstrate an enrichment of these purified CSCs by analyzing the isolated cells for known stem cell markers Oct4, Nanog, and Prom1 (CD133) and cell surface expression of CD177 and CD133. The CSCs exhibit increased chemoresistance. This method for isolation of CSCs is a useful tool for studying the role of CSCs in chemoresistance and tumor relapse.

Cancer stem cells (CSCs) are&#160;implicated in tumor relapse due to chemoresistance. We have optimized a protocol for selection and expansion of CSCs from ovarian cancer cell lines. By treating cells with the chemotherapeutic cisplatin and culturing&#160;in a stem cell promoting media we enrich for non-adherent CSC cultures.

Enriquecimento para resistente à quimioterapia do cancro do ovário células-tronco de linhas de células humanas

Cancer stem cells (CSCs) are defined as a subset of slow cycling and undifferentiated cells that divide asymmetrically to generate highly proliferative, ...

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 ...

Methods for Culturing Human Femur Tissue Explants to Study Breast Cancer Cell Colonization of the Metastatic Niche

Bone is the most common site of breast cancer metastasis. Although it is widely accepted that the microenvironment influences cancer cell behavior, little is known about breast cancer cell properties and behaviors within the native microenvironment of human bone tissue.We have developed approaches to track, quantify and modulate human breast cancer cells within the microenvironment of cultured human bone tissue fragments isolated from discarded femoral heads following total hip replacement surgeries. Using breast cancer cells engineered for luciferase and enhanced green fluorescent protein (EGFP) expression, we are able to reproducibly quantitate migration and proliferation patterns using bioluminescence imaging (BLI), track cell interactions within the bone fragments using fluorescence microscopy, and evaluate breast cells after colonization with flow cytometry. The key advantages of this model include: 1) a native, architecturally intact tissue microenvironment that includes relevant human cell types, and 2) direct access to the microenvironment, which facilitates rapid quantitative and qualitative monitoring and perturbation of breast and bone cell properties, behaviors and interactions. A primary limitation, at present, is the finite viability of the tissue fragments, which confines the window of study to short-term culture. Applications of the model system include studying the basic biology of&#160;breast cancer and other bone-seeking malignancies within the metastatic niche, and developing therapeutic strategies to effectively target breast cancer cells in bone tissues.

Protocols are described for studying breast cancer cell migration, proliferation and colonization in a human bone tissue explant model system.

Métodos para a cultura fémur humano explantes de tecido para o Estudo de Câncer de Mama Colonização celular do Niche metastático

Bone is the most common site of breast cancer metastasis. Although it is widely accepted that the microenvironment influences cancer cell behavior, little ...