Name: evaluation of stem cell properties in human ovarian carcinoma cells using multi and single cell-based spheres assays
Uploaded: 2015-01-03T15:00:00.000+00:00
Duration: 8 min 39 s
Description: Watch this Scientific Journal Video about Evaluation of Stem Cell Properties in Human Ovarian Carcinoma Cells Using Multi and Single Cell-based Spheres Assays at JoVE.com

This study was supported by a grant from the Baden-W&#252;rttemberg Stiftung (Adult Stem Cells Program II) awarded to C.L. We thank Dr. Martina Konantz for critical input and review of the manuscript. We thank Emmanuel Traunecker and Toni Krebs from the DBM FACS Facility (University Hospital Basel) for assistance with FACS sorting.

1. Geração de células humanas de carcinoma de ovário OVCAR-3 estavelmente transduzidas com Lentiviruses Contendo o Reporter Construct SOX2 Região Regulatory <ol><li> Gerar partículas lentivirais por transfecção da linha celular 293T HEK-embalagem com uma construção repórter reconhecer uma região reguladora SOX2 como descrito 10,21. NOTA: O repórter construir contém ainda um domínio desestabilização do System Shield ProteoTuner à frente da proteína tdTomato fluorescência. Shield1 se liga ao domínio desestabilização impedindo assim o proteassoma para degradar a proteína de fluorescência 22. </li><li> Transduzir células OVCAR-3 com partículas lentivirais durante um período de tempo de 24 horas. Em seguida, remover o sobrenadante viral e lavar as células com solução salina de fosfato tamponada (PBS) e cultivadas em meio completo (meio RPMI suplementado com 10% de FBS, 100 U / ml de penicilina, 100 ug / ml de estreptomicina). </li><li> 48 horas depois, 10 ug / ml puromicina foram adicionados às culturas e mantidas durante 5 dias para permitir a selecção de células transduzidas adequadamente. </li></ol> 2. Preparação de células de classificação e Galvanização <ol><li> Adicionar Shield1 a 1: 1000 de diluição 24 h antes da separação de células. Use estavelmente transduzidas OVCAR-3 em células sem tratamento Shield1 como controlos negativos (Figura 1). Aspirar meios de balão, lavar as células com PBS 1x e trypsinize células com 0,05% Tripsina-EDTA durante 3 min. </li><li> Pare tripsina utilizando meio completo (ver acima), contar o número de células, as células de centrifugação a 300 xg à temperatura ambiente (15 - 25 ° C) durante 5 min. </li><li> Decantar o sobrenadante e ressuspender as células cuidadosamente em 0,5-1 ml de PBS estéril. </li><li> Use 40 um filtro cap filtro de células para obter a suspensão de uma única célula. </li><li> Ajustar a contagem de células a 5 milhões de células por ml. </li><li> Prepare baixa fixação placas ultra-96 poços com 100 ul esferas médio (MEGM suplementado com fatores de crescimento, citocinas e suplementos,B-27, heparina-sódio; ou DMEM / F12 suplementado com factores de crescimento, citocinas e suplementos, B-27, heparina-sódio, com ou sem adição de 1% de metilcelulose, ver também a Tabela 1). Opcionalmente adicionar antibióticos para o meio a uma concentração de 100 U / ml de penicilina e 100 ug / ml de estreptomicina para minimizar o risco de possível contaminação. </li><li> Ordenar as células em RFP- preparadas placas de 96 poços a partir de cima e RFP +, uma célula por cavidade (ensaio de esferas único baseado em células), e 100 células por poço (de ensaio de multi esferas baseados em células), respectivamente. Execute classificador de células tipo em comercialmente disponível (ver Materiais) usando o modo de única célula, Sort setup: 100 μ bocal, pressão do invólucro 20 psi, e rendimento de máscara 0, pureza máscara de 32, a máscara de fase 16. </li><li> Avaliar a eficiência do plaqueamento por microscopicamente conseguir poços contendo células (para o ensaio de base celular único) e por contagem do número de células em poços individuais (para o ensaio baseado em células múltiplas; Figura 2 </strong&gt;). </li><li> Incubar as células em condições normais médias em esferas (para a composição ver passo 2.6) a 37 ° C e 5% de CO 2. Suplemento de bFGF por dia (20 ng / ml) e EGF (20 ng / ml). </li><li> Após uma semana, contar o número de esferas de tumor emergente usando um microscópio padrão com 4X ou ampliação de 10X e um microscópio de fluorescência para detectar o sinal de fluorescência a partir do sistema repórter integrada. Contagem de esferas com um diâmetro superior a 100 um, como esferas &quot;grandes&quot; e as esferas com um diâmetro de 50 - 100 mm como &quot;pequenos&quot; esferas (Figura 3). Tenha certeza de que você contar esferas reais e não celular clusters. NOTA: Em ensaios baseados em células individuais formação esfera é mais fácil para marcar microscopicamente após 10 (contra 7) dias de cultura. </li><li> Calcular a proporção de células formadoras de esfera em RFP + e células, respectivamente RFP- em ensaios baseados em células individuais (uma placa de 96 poços para cada experiência individual) ou de multi-célula baesferas ensaios sed (um bem para cada experimento indivíduo), como apresentado por Shaw et al. 16 NOTA: Proporção de células formando esfera (%) = (número de esferas) / (número de células semeadas) x 100 </li></ol> 3. Passaging Serial de Esferas <ol><li> Colocar o conteúdo de cada cavidade dentro de um tubo estéril adequado e centrifugar a 300 xg durante 10 min à temperatura ambiente. Para baseados em células múltiplas esferas ensaios, reúna as esferas de um bem. Lava-se a bem 3 - 5 vezes com PBS e centrifugação mais 2 min. Para individuais baseados em células esferas ensaios, coletar esferas individuais. Devido ao baixo número de células, utilizar tubos de 1,5 ml para centrifugação e lavagem passos. </li><li> Remover o sobrenadante e ressuspender o sedimento em 200 ul de 0,05% de tripsina-EDTA. </li><li> A fim de conseguir a separação celular óptimo, incubar a suspensão de células a 37 ° C durante 5 min num agitador suave. Otimizar tripsinizaï¿½o tempo para a sua linha de células de menor taxa de morte celular: se nenhuma grandeesferas é triturado visível delicadamente com uma pipeta de ponta de 100 mL. No caso de grandes esferas ainda estão presentes, incube com tripsina outro 3 min e, em seguida, avançar para a etapa de trituração. No caso de um único ensaios baseados em células para se certificar de optimizar o tempo de rendimento óptimo das células de células vivas durante o passo de tripsinização. </li><li> Para inactivar a tripsina, adicionar 500 ul meio completo e centrifugação a 300 xg durante 10 min, no caso de ensaios de células individuais, centrifugar durante mais 2 min. </li><li> Remover sobrenadante e ressuspender as células em meio de esferas cuidadosamente. </li><li> Usar um filtro de 40 um filtro de células de tampão para se obter uma suspensão de célula única. </li><li> No caso de se utilizar células RFP- em ensaios bassed de células multi-RFP + e, avaliar a percentagem de células fluorescentes em cada poço após ressuspensão através de análise de citometria de fluxo. </li><li> Para os ensaios de replating série de células individuais, sementes de 1 célula por cavidade em um novo ultra-baixo fixação placa de 96 poços preparados tal como acima descrito. A partir de uma esfera individual, semear aproximadamente 20 poços individuais. Para os ensaios de esferas replating primários múltiplos baseados em células, as células de semente obtido a partir de um poço de esferas primárias para uma nova placa de 96 poços e contar o número de células no dia seguinte por microscopia. </li><li> Avaliar a percentagem de células formadoras de esfera em esferas secundárias ensaios usando a fórmula descrita no passo 2.11. </li></ol> Análise 4. Resultado <ol><li> Analisar os resultados de experimentos realizados em triplicatas independentes e usar o teste t de Student dois lados para analisar os valores normalmente distribuídos e de outra forma Mann-Whitney-testes para análise estatística. </li></ol>

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The authors have nothing to disclose.

Esferas culturas é um método amplamente utilizado para testar o potencial de células estaminais do cancro e para enriquecer as células estaminais do tipo em uma ampla variedade de células tumorais humanas 15,25,26. Sob estas condições de cultura, as células cancerosas que não têm capacidade de auto-renovação são esperados para diferenciar e eventualmente sofrem morte celular. Embora eles podem, inicialmente, formar grupos de células tumorais ou mesmo esferas especialmente em ensaios preliminares...

There is increasing evidence that ovarian carcinomas are comprised of heterogeneous mixtures of cells and harbor so-called &#8220;cancer stem cells&#8221; (CSCs) responsible for disease initiation, maintenance and relapse after conventional cytotoxic therapies1-3. Therefore, the development of molecular strategies targeting ovarian CSCs is an important goal and promises to improve the therapy of ovarian cancer patients.
A pre-requisite for the understanding of the molecular features of CSCs is their reliable isolation from the non-CSCs. However, identification of ovarian CSCs appears challenging. While CD133 expression and aldehyde dehydrogenase (ALDH) activity4,5 have been reported to mark ovarian CSCs, some data indicate that these markers are unstable6. Consistently, in ovarian cancer, other than for example in breast carcinoma7, expression of ALDH1 associates with favorable outcome8 and expression of the proposed stem cell marker CD44 variant has no prognostic value9. More recently, we have shown that expression of the embryonic stem cell protein SOX2 confers stemness to ovarian carcinoma cells10 and high SOX2 expression associates with clinically aggressive ovarian and breast carcinomas11,12. Therefore, in this report we use a lentiviral reporter construct containing a red fluorescence protein (RFP) whose expression is controlled by a SOX2 regulatory region, as a method to isolate putative ovarian CSCs.
By definition, CSCs can both self-renew and differentiate, giving rise to all tumor cell types. Putative CSC populations need to be analyzed in functional assays performed in vivo. For obvious reasons, in human cells such functional tests are confined to xenograft assays, comprising mostly transplantation of human tumor cells into immuno-compromised mice10,13.
An alternative in vitro method was offered by Brent Reynolds and Sam Weiss who firstly reported the so-called neurosphere assay as a surrogate assay evaluating stem potential in neural cells14. Dontu and colleagues later confirmed the use of this assay for evaluation of stem cell potential in breast cells15,16. Here, human mammary cells were plated in different numbers in serum-free medium supplemented with epidermal growth factor (EGF), basic fibroblast growth factor (bFGF), B-27 and heparin and cultured under non-adherent conditions for seven to ten days before sphere formation was scored by microscopy. Following this protocol with some adjustments in cell numbers, growth medium and supplements, several groups have explored in vitro stem cell potential from several cancer types such as breast17, brain18, pancreas19 and colon20 tumors. In ovarian carcinoma, we have recently reported feasibility of the spheres assay and compared its results to those collected in in vivo murine xenograft models10. We found that overexpression of the stem cell protein SOX2 enhanced both in vitro sphere formation as well as in vivo tumorigenicity of human ovarian carcinoma cells10. However, the frequency of sphere-initiating cells was higher than the frequency of tumor-initiating cells measured in vivo10 suggesting that either the sphere assay may lead to false positive results due to technical reasons or, alternatively, the in vivo assay may be inefficient and result in false negative results.
In this report, we analyze multi cell-based ovarian spheres assays in more detail, review the different protocols available in the literature and compare them to a single cell-based assay. We show that the single cell-based assay provides more accurate and reproducible results than multi cell-based assays, which can be highly influenced by the density of plated cells unless methylcellulose is added to the cultures to immobilize cells. However, also in single cell-based assays, in vitro sphere-initiating potential is observed at higher frequency than in vivo tumor-initiating potential.

<table><tbody><tr><td>Low-attachment plate</td><td>Corning</td><td>3474</td><td></td></tr><tr><td>MEGM</td><td>Lonza</td><td>CC-3151</td><td></td></tr><tr><td>Insulin</td><td>Lonza</td><td>CC-4136</td><td>SingleQuots&amp;trade; Kit</td></tr><tr><td>Hydrocortisone</td><td>Lonza</td><td>CC-4136</td><td>SingleQuots&amp;trade; Kit</td></tr><tr><td>EGF</td><td>Lonza</td><td>CC-4136</td><td>SingleQuots&amp;trade; Kit</td></tr><tr><td>EGF</td><td>Sigma</td><td>E9644</td><td>end concentration: 20 ng/ml</td></tr><tr><td>FGF</td><td>PeproTech</td><td>100-18B</td><td>end concentration: 20 ng/ml</td></tr><tr><td>B-27</td><td>Invitrogen/ Gibco</td><td>17504-044</td><td>end concentration: 1X</td></tr><tr><td>Heparin-Natrium-25000 IE</td><td>Ratiopharm</td><td>N68542.02</td><td>dilution 1:1,000</td></tr><tr><td>Pen/Strep</td><td>Gibco</td><td>15140-122</td><td></td></tr><tr><td>FCS</td><td>Gibco</td><td>10500-064</td><td></td></tr><tr><td>RPMI 1640</td><td>Gibco</td><td>21875-034</td><td></td></tr><tr><td>Trypsin-EDTA</td><td>Gibco</td><td>25300-054</td><td></td></tr><tr><td>Dulbecco&amp;rsquo;s PBS (1X)</td><td>Gibco</td><td>14190-094</td><td></td></tr><tr><td>Shield1</td><td>Clontech</td><td>632189</td><td>dilution 1:1,000</td></tr><tr><td>DMEM/F12</td><td>Gibco</td><td>21041-025</td><td></td></tr><tr><td>DMEM/F12 (powder)</td><td>Gibco</td><td>42400-010</td><td></td></tr><tr><td>Methyl cellulose</td><td>Sigma</td><td>M0387</td><td></td></tr><tr><td>Puromycin dihydrochloride</td><td>Applichem</td><td>A2856</td><td></td></tr><tr><td>Cell sorter</td><td>BD</td><td></td><td>Aria III cell sorter</td></tr><tr><td>FACS analyser</td><td>BD</td><td></td><td>Accuri c6 flow cytometer</td></tr><tr><td>Microscope</td><td>Olympus</td><td></td><td>IX50 Osiris</td></tr></tbody></table>

evaluation of stem cell properties in human ovarian carcinoma cells using multi and single cell-based spheres assays

Years of research indicates that ovarian cancers harbor a heterogeneous mixture of cells including a subpopulation of so-called &#8220;cancer stem cells&#8221; (CSCs) responsible for tumor initiation, maintenance and relapse following conventional chemotherapies. Identification of ovarian CSCs is therefore an important goal. A commonly used method to assess CSC potential in vitro is the spheres assay in which cells are plated under non-adherent culture conditions in serum-free medium supplemented with growth factors and sphere formation is scored after a few days. Here, we review currently available protocols for human ovarian cancer spheres assays and perform a side-by-side analysis between commonly used multi cell-based assays and a more accurate system based on single cell plating. Our results indicate that both multi cell-based as well as single cell-based spheres assays can be used to investigate sphere formation in vitro. The more laborious and expensive single cell-based assays are more suitable for functional assessment of individual cells and lead to overall more accurate results while multi cell-based assays can be strongly influenced by the density of plated cells and require titration experiments upfront. Methylcellulose supplementation to multi cell-based assays can be effectively used to reduce mechanical artifacts.

Em ensaios de esferas convencionais, cerca de 40% de RFP + OVCAR-3 células vs. 20% de células RFP- deu origem a uma esfera tumor individual no ensaio de esferas primário (Figura 4A). Além disso, as esferas formadas por RFP + células eram maiores em tamanho do que os que são formados por células RFP-. Quando colocadas em ensaios baseados em células individuais, células RFP + também formou mais esferas do que as células RFP-, confirmando os resultados acima. No enta...

Watch this Scientific Journal Video about Evaluation of Stem Cell Properties in Human Ovarian Carcinoma Cells Using Multi and Single Cell-based Spheres Assays at JoVE.com

Evaluation of Stem Cell Properties in Human Ovarian Carcinoma Cells Using Multi and Single Cell-based Spheres Assays

In vitro spheres assays are commonly used to identify cancer stem cells. Here we compare single with multi cell-based spheres assays. The more laborious single cell-based assays or methylcellulose supplementation give more accurate results while multi cell-based assays performed in liquid medium can be highly influenced by cell density.

Avaliação das Propriedades Stem Cell em carcinomas de células do ovário humano utilizar multi e individuais baseados em células Esferas Ensaios

Years of research indicates that ovarian cancers harbor a heterogeneous mixture of cells including a subpopulation of so-called &#8220;cancer stem ...

evaluation-stem-cell-properties-human-ovarian-carcinoma-cells-using

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Medicine

9.5K visualizações.  University Hospital Basel. In vitro spheres assays are commonly used to identify cancer stem cells. Here we compare single with multi cell-based spheres assays. The more laborious single cell-based assays or methylcellulose supplementation give more accurate results while multi cell-based assays performed in liquid medium can be highly influenced by cell density.

Vídeo: Evaluation of Stem Cell Properties in Human Ovarian Carcinoma Cells Using Multi and Single Cell-based Spheres Assays

Establishment of Cancer Stem Cell Cultures from Human Conventional Osteosarcoma

The current improvements in therapy against osteosarcoma (OS) have prolonged the lives of cancer patients, but the survival rate of five years remains poor when metastasis has occurred. The Cancer Stem Cell (CSC) theory holds that there is a subset of tumor cells within the tumor that have stem-like characteristics, including the capacity to maintain the tumor and to resist multidrug chemotherapy. Therefore, a better understanding of OS biology and pathogenesis is needed in order to advance the development of targeted therapies to eradicate this particular subset and to reduce morbidity and mortality among patients. Isolating CSCs, establishing cell cultures of CSCs, and studying their biology are important steps to improving our understanding of OS biology and pathogenesis. The establishment of human-derived OS-CSCs from biopsies of OS has been made possible using several methods, including the capacity to create 3-dimensional stem cell cultures under nonadherent conditions. Under these conditions, CSCs are able to create spherical floating colonies formed by daughter stem cells; these colonies are termed &#34;cellular spheres&#34;. Here, we describe a method to establish CSC cultures from primary cell cultures of conventional OS obtained from OS biopsies. We clearly describe the several passages required to isolate and characterize CSCs.

The presence of cancer stem cells (CSCs) in bone sarcomas has recently been linked to their pathogenesis. In this article, we present the isolation of CSCs from primary cell cultures obtained from human biopsies of conventional osteosarcoma (OS) using the ability of CSCs to grow under nonadherent conditions.

Establishment of Cancer Stem Cell Cultures de Human osteossarcoma convencional

The current improvements in therapy against osteosarcoma (OS) have prolonged the lives of cancer patients, but the survival rate of five years remains ...

Pesquisa do câncer

Heterotypic Three-dimensional In Vitro Modeling of Stromal-Epithelial Interactions During Ovarian Cancer Initiation and Progression

Epithelial ovarian cancers (EOCs) are the leading cause of death from gynecological malignancy in Western societies. Despite advances in surgical treatments and improved platinum-based chemotherapies, there has been little improvement in EOC survival rates for more than four decades 1,2. Whilst stage I tumors have 5-year survival rates &gt;85%, survival rates for stage III/IV disease are &lt;40%. Thus, the high rates of mortality for EOC could be significantly decreased if tumors were detected at earlier, more treatable, stages 3-5. At present, the molecular genetic and biological basis of early stage disease development is poorly understood. More specifically, little is known about the role of the microenvironment during tumor initiation; but known risk factors for EOCs (e.g. age and parity) suggest that the microenvironment plays a key role in the early genesis of EOCs. We therefore developed three-dimensional heterotypic models of both the normal ovary and of early stage ovarian cancers. For the normal ovary, we co-cultured normal ovarian surface epithelial (IOSE) and normal stromal fibroblast (INOF)&nbsp;cells, immortalized by retrovrial transduction of the catalytic subunit of human telomerase holoenzyme (hTERT) to extend the lifespan of these cells in culture. To model the earliest stages of ovarian epithelial cell transformation, overexpression of the CMYC oncogene in IOSE cells, again co-cultured with INOF cells. These heterotypic models were used to investigate the effects of aging and senescence on the transformation and invasion of epithelial cells. Here we describe the methodological steps in development of these three-dimensional model; these methodologies aren't specific to the development of normal ovary and ovarian cancer tissues, and could be used to study other tissue types where stromal and epithelial cell interactions are a fundamental aspect of the tissue maintenance and disease development.

Heterotypic Three-dimensional In Vitro Modeling of Stromal-Epithelial Interactions During Ovarian Cancer Initiation and Progression

We describe methodologies for establishing in vitro heterotypic three-dimensional models comprising ovarian fibroblasts and normal ovarian surface or ovarian cancer epithelial cells. We discuss the use of these models to study stromal-epithelial interactions that occur during ovarian cancer development.

Heterotípica tridimensional<em&gt; In Vitro</em&gt; Modelagem de Estroma-epitelial de ovário Interações durante o início e progressão do câncer

Epithelial ovarian cancers (EOCs) are the leading cause of death from gynecological malignancy in Western societies. Despite advances in surgical ...

Medicina

Physiologic Patient Derived 3D Spheroids for Anti-neoplastic Drug Screening to Target Cancer Stem Cells

In this protocol, we outline the procedure for generation of tumor spheroids within 384-well hanging droplets to allow for high-throughput screening of anti-cancer therapeutics in a physiologically representative microenvironment. We outline the formation of patient derived cancer stem cell spheroids, as well as, the manipulation of these spheroids for thorough analysis following drug treatment. Specifically, we describe collection of spheroid morphology, proliferation, viability, drug toxicity, cell phenotype and cell localization data. This protocol focuses heavily on analysis techniques that are easily implemented using the 384-well hanging drop platform, making it ideal for high throughput drug screening. While we emphasize the importance of this model in ovarian cancer studies and cancer stem cell research, the 384-well platform is amenable to research of other cancer types and disease models, extending the utility of the platform to many fields. By improving the speed of personalized drug screening and the quality of screening results through easily implemented physiologically representative 3D cultures, this platform is predicted to aid in the development of new therapeutics and patient-specific treatment strategies, and thus have wide-reaching clinical impact.

This protocol describes generation of patient-derived spheroids, and downstream analysis including quantification of proliferation, cytotoxicity testing, flow cytometry, immunofluorescence staining and confocal imaging, in order to assess drug candidates&#8217; potential as anti-neoplastic therapeutics. This protocol supports precision medicine with identification of specific drugs for each patient and stage of disease.

Spheroids 3D derivados do paciente fisiológico para a seleção antineoplástica da droga para alvejar pilhas de haste do cancro

In this protocol, we outline the procedure for generation of tumor spheroids within 384-well hanging droplets to allow for high-throughput screening of ...

Obtaining Cancer Stem Cell Spheres from Gynecological and Breast Cancer Tumors

Cancer stem cells (CSC) are a small population with self-renewal and plasticity which are responsible for tumorigenesis, resistance to treatment and recurrent disease. This population can be identified by surface markers, enzymatic activity and a functional profile. These approaches per se are limited, due to phenotypic heterogeneity and CSC plasticity. Here, we update the sphere-forming protocol to obtain CSC spheres from breast and gynecological cancers, assessing functional properties, CSC markers and protein expression. The spheres are obtained with single-cell seeding at low density in suspension culture, using a semi-solid methylcellulose medium to avoid migration and aggregates. This profitable protocol can be used in cancer cell lines but also in primary tumors. The tridimensional non-adherent suspension culture thought to mimic the tumor microenvironment, particularly the CSC-niche, is supplemented with epidermal growth factor and basic fibroblast growth factor to ensure CSC signaling. Aiming for robust identification of CSC, we propose a complementary approach, combining functional and phenotypic evaluation. Sphere-forming capacity, self-renewal and sphere projection area establish CSC functional properties. Additionally, characterization comprises flow cytometry evaluation of the markers, represented by CD44+/CD24- and CD133, and Western blot, considering ALDH. The presented protocol was also optimized for primary tumor samples, following a sample digestion procedure, useful for translational research.

The aim of this methodology is to identify cancer stem cells (CSC) in cancer cell lines and primary human tumor samples with the sphere-forming protocol, in a robust manner, using functional assays and phenotypic characterization with flow cytometry and Western blot.

Obtenção de esferas de células-tronco cancerígenas de tumores ginecológicos e de câncer de mama

Cancer stem cells (CSC) are a small population with self-renewal and plasticity which are responsible for tumorigenesis, resistance to treatment and ...

Isolation and Expansion of Human Glioblastoma Multiforme Tumor Cells Using the Neurosphere Assay

Stem-like cells have been isolated in tumors such as breast, lung, colon, prostate and brain. A critical issue in all these tumors, especially in glioblastoma mutliforme (GBM), is to identify and isolate tumor initiating cell population(s) to investigate their role in tumor formation, progression, and recurrence. Understanding tumor initiating cell populations will provide clues to finding effective therapeutic approaches for these tumors. The neurosphere assay (NSA) due to its simplicity and reproducibility has been used as the method of choice for isolation and propagation of many of this tumor cells. This protocol demonstrates the neurosphere culture method to isolate and expand stem-like cells in surgically resected human GBM tumor tissue. The procedures include an initial chemical digestion and mechanical dissociation of tumor tissue, and subsequently plating the resulting single cell suspension in NSA culture. After 7-10 days, primary neurospheres of 150-200 &mu;m in diameter can be observed and are ready for further passaging and expansion.

This video protocol demonstrates the isolation and expansion of stem like cells from surgically resected human glioblastoma mutliforme (GBM) tumor tissue using the neurosphere assay culture method.

Isolamento e Expansão da Human Glioblastoma Multiforme Células Tumorais Utilizando o Ensaio Neurosphere

Stem-like cells have been isolated in tumors such as breast, lung, colon, prostate and brain. A critical issue in all these tumors, especially in ...

Neurociência

Assessment of Ovarian Cancer Spheroid Attachment and Invasion of Mesothelial Cells in Real Time

Ovarian cancers metastasize by shedding into the peritoneal fluid and dispersing to distal sites within the peritoneum. Monolayer cultures do not accurately model the behaviors of cancer cells within a nonadherent environment, as cancer cells inherently aggregate into multicellular structures which contribute to the metastatic process by attaching to and invading the peritoneal lining to form secondary tumors. To model this important stage of ovarian cancer metastasis, multicellular aggregates, or spheroids, can be generated from established ovarian cancer cell lines maintained under nonadherent conditions. To mimic the peritoneal microenvironment encountered by tumor cells in vivo, a spheroid-mesothelial co-culture model was established in which preformed spheroids are plated on top of a human mesothelial cell monolayer, formed over an extracellular matrix barrier. Methods were then developed using a real-time cell analyzer to conduct quantitative real time measurements of the invasive capacity of different ovarian cancer cell lines grown as spheroids. This approach allows for the continuous measurement of invasion over long periods of time, which has several advantages over traditional endpoint assays and more laborious real time microscopy image analyses. In short, this method enables a rapid, determination of factors which regulate the interactions between ovarian cancer spheroid cells invading through mesothelial and matrix barriers over time.

Ovarian cancer cell invasion into the mesothelial lining of the peritoneum is a dynamic process over time. Utilizing a real time analyzer, the invasive capacity of ovarian cancer cells in a spheroid-mesothelial cell co-culture model can be quantified over prolonged time periods, providing insights into factors regulating the metastatic process.

Avaliação do cancro do ovário esferóide Apego e invasão de células mesoteliais em Tempo real

Ovarian cancers metastasize by shedding into the peritoneal fluid and dispersing to distal sites within the peritoneum. Monolayer cultures do not ...

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, ...

Mammosphere Formation Assay from Human Breast Cancer Tissues and Cell Lines

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 self-renew while giving rise to more differentiated progeny. Understanding and targeting these cancer stem cells in breast cancer, which may possess enhanced chemo- and radio-resistance compared to the non-stem tumor bulk, has become an important research area. Markers including CD44, CD24, and ALDH activity can be assessed using fluorescence activated cell sorting (FACS) to prospectively isolate cells that display enhanced tumorigenicity when implanted into immunocompromised mice: the mammosphere assay has also become widely used for its ability to retrospectively identify sphere-forming cells that develop from single stem cell-like clones. Here we outline approaches for the appropriate culturing of mammospheres from cell lines or primary patient samples, their passaging, and calculations to estimate sphere forming efficiency (SFE). First we discuss key considerations and pitfalls in the appropriate planning and interpretation of mammosphere experiments.

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 ...

Studying Pancreatic Cancer Stem Cell Characteristics for Developing New Treatment Strategies

Pancreatic ductal adenocarcinoma (PDAC) contains a subset of exclusively tumorigenic cancer stem cells (CSCs) which have been shown to drive tumor initiation, metastasis and resistance to radio- and chemotherapy. Here we describe a specific methodology for culturing primary human pancreatic CSCs as tumor spheres in anchorage-independent conditions. Cells are grown in serum-free, non-adherent conditions in order to enrich for CSCs while their more differentiated progenies do not survive and proliferate during the initial phase following seeding of single cells. This assay can be used to estimate the percentage of CSCs present in a population of tumor cells. Both size (which can range from 35 to 250 micrometers) and number of tumor spheres formed represents CSC activity harbored in either bulk populations of cultured cancer cells or freshly harvested and digested tumors 1,2. Using this assay, we recently found that metformin selectively ablates pancreatic CSCs; a finding that was subsequently further corroborated by demonstrating diminished expression of pluripotency-associated genes/surface markers and reduced in vivo tumorigenicity of metformin-treated cells. As the final step for preclinical development we treated mice bearing established tumors with metformin and found significantly prolonged survival. Clinical studies testing the use of metformin in patients with PDAC are currently underway (e.g., NCT01210911, NCT01167738, and NCT01488552). Mechanistically, we found that metformin induces a fatal energy crisis in CSCs by enhancing reactive oxygen species (ROS) production and reducing mitochondrial transmembrane potential. In contrast, non-CSCs were not eliminated by metformin treatment, but rather underwent reversible cell cycle arrest. Therefore, our study serves as a successful example for the potential of in vitro sphere formation as a screening tool to identify compounds that potentially target CSCs, but this technique will require further in vitro and in vivo validation to eliminate false discoveries.

Pancreatic cancer stem cells (CSCs) can be expanded in vitro using the anchorage-independent sphere culture technique, which represents a powerful tool to study CSC biology and can serve as the first step to develop novel CSC-targeting therapies. Here the methodology for expanding, analyzing and targeting of pancreatic CSCs is provided.

Estudar o cancro do pâncreas Stem características celulares para desenvolver estratégias Novo tratamento

Pancreatic ductal adenocarcinoma (PDAC) contains a subset of exclusively tumorigenic cancer stem cells (CSCs) which have been shown to drive tumor ...

Evaluating the Angiogenetic Properties of Ovarian Cancer Stem-Like Cells using the Three-Dimensional Co-Culture System, NICO-1

Cancer stem cells (CSCs) reside in a supportive niche, constituting a microenvironment comprised of adjacent stromal cells, vessels, and extracellular matrix. The ability of CSCs to participate in the development of endothelium constitutes an important characteristic that directly contributes to the general understanding of the mechanisms of tumorigenesis and tumor metastasis. The purpose of this work is to establish a reproducible methodology to investigate the tumor-initiation capability of ovarian cancer stem cells (OCSCs). Herein, we examined the neovascularization mechanism between endothelial cells and OCSCs along with the morphological changes of endothelial cells using the in vitro co-culture model NICO-1. This protocol allows visualization of the neovascularization step surrounding the OCSCs in a time course manner. The technique can provide insight regarding the angiogenetic properties of OCSCs in tumor metastasis.

Ovarian cancer stem cells (OCSC) are responsible for cancer initiation, recurrence, therapeutic resistance, and metastasis. The OCSC vascular niche is considered to promote self-renewal of OCSCs, leading to chemoresistance. This protocol provides the basis for establishing a reproducible OCSC vascular niche model in vitro.

Avaliando as propriedades angiogenéticas de células-tronco do câncer de ovário usando o Sistema de Cocultura Tridimensional, NICO-1

Cancer stem cells (CSCs) reside in a supportive niche, constituting a microenvironment comprised of adjacent stromal cells, vessels, and extracellular ...