NIH hibe P30 CA051008 ve T32 CA009686 (ATR) tarafından desteklenir.

Sferoidlerin 1. Üretim <ol><li> Bir PBS kullanarak 70% konfluansa ~ adherent kanseri hücre kültürleri ayırarak damla kültürleri asılı tek hücre süspansiyonu hazırlamak% 0.05 tripsin-EDTA solüsyonuna maruz bırakılarak, ardından yıkama. <ol><li> Hücre kültür ortamı ile tripsin solüsyonu nötralize ve hücre süspansiyonu, bir kısım kullanarak hücreleri sayın. Not: Hücre hattı bağlıdır belirli bir hücre kültür ortamı, test edilen. Hücre kültür ortamı genellikle DMEM +% 10 FBS olduğu, ATCC medya önerileri uygulayın. Daha fazla bilgi Malzemeleri Tablo bulunabilir. </li><li> Hücre kültür ortamı 20 ul damla başına 500-1000 hücre ekimi için izin vermek için bir seyreltme gerçekleştirin. </li></ol></li><li> 10 cm çanak Edinme ve alt steril PBS 5 ml ekleyin. Not: Bu adım asılı buharlaşma damla korur. Düşük maliyetli &quot;bakteriyolojik notu&quot; yemekleri, hücre kültürü sınıf yemekleri yerine kullanılabilecek kadar hücreler devamı olmazKültür yüzey hareket ederler. </li><li> Kapağın iç yüzeyine seyreltilmiş hücre süspansiyonu, 20 ul damlalar aktarmak için bir çok kanallı pipet kullanın. <ol><li> Pipet 40 10 cm çanak kapağı üzerine (8 damla 5 satır) düşer. </li></ol></li><li> Kültür çanak üzerinde kapağı ve yer ters çevirin. Sferoidler oluşturmak için 72 saat boyunca 37 ° C &#39;de asılı damla kültürleri inkübe edin. <ol><li> Kendine güvenen, henüz kontrollü bir şekilde kapağı çevirin. Not: Çok hızlı veya çok yavaş kapağı Inverting damlacıklar kaydırmaya neden olabilir. Diğerleri, kompakt agrega üretilmesi için fazla 72 saat gerekebilir Bazı hücre hatları, 48 saat ya da daha az parçacıklarının oluşturabilir. </li></ol></li></ol> 3D Matrix içine sferoitlerin 2. gömülmesi <ol><li> Gece boyunca sferoidler, gömme işlemi öncesinde 4 ° C&#39;de büyüme faktörü azaltılmış bazal membran malzeme bir kısım çözülme. <ol><li> İsteğe bağlı: Önceden ECM ile Katman kuyu doku kültürlerdeki potansiyel sfero etkileşimi önlemek içinyüzeye yeniden. <ol><li> 24 oyuklu bir plaka üzerinde oyuk başına ECM&#39;nin pipetleyin 200 ul. </li><li> ECM tüm kuyu yüzeyini kaplayan emin olmak için plakayı eğin. </li><li> Dikkatle bir pipet ile aşırı ECM çıkarın. </li><li> 3 saat oda sıcaklığında ya da gece boyunca 4 ° C&#39;de: kuyu kuruyana kadar plaka inkübe edin. </li></ol></li></ol></li><li> Doku kültürü çanak kapağı devirme ve medyayı bir araya getirerek parçacıklarının toplayın. 1.5 ml mikrosantrifüj tüp içine sferoidlerle medya aktarın. </li><li> Sferoidler mikrosantrifüj tüp dibinde yerleşmek için 10 dakika bekleyin. Sferoidler gözle görünür olmalıdır. </li><li> . Soğuk (4 ° C) 100 ul bir ayrı ön-soğutulmuş bir tüp içinde kollajen tip ile bazal membran malzeme 100 ul karıştırın erken katılaşmasını önlemek için ya da bir jel, 4 ° C &#39;de karışımı tutun. <ol><li> Küçük hacimli transfer eğer önceden soğutulmuş pipet ipuçlarını kullanın. </li><li> Dikkatli verBen hava kabarcığı oluşumunu önlemek için bazal membran malzeme ve kollajen tip karıştırma. Not: jel gömülü hale eğer Hava kabarcıkları protokolde daha sonra görüntüleme engelleyebilir. </li></ol></li><li> Mikrosantrifüj tüp 40 ul alt kısmından parçacıklarının aspire ve ben karışımı kollajen bazal membran malzemeleri / tip ile birleştirir. Karıştırma sırasında hava kabarcığı oluşumunu önlemek için dikkatli olun. Not: Çözelti 100 ul kollajen tip I ve sferoitlerin 40 ul 4 bağımsız 3D kültürler için yeterli malzeme yaratacak, 100 ul bazal membran malzemelerinin içeren. Bu büyütülüyor veya aşağı olabilir. </li><li> Pipet, 24 oyuklu bir plaka üzerinde kuyuların merkezlerine viskoz karışımın 40 ul düşer. Kuyunun tarafına çalışmasını karışımı önlemek için plaka düz tutun. Not: 24 oyuklu bir plaka üzerinde bir tek sütun - 4 kuyu - Her bir durumda test edilecek için tavsiye edilir. </li><li> Plaka int yerleştirinoa 37 ° C inkübatör ve 30 dakika boyunca rahatsız edilmeden bırakın. 3D kültür bu dönemde polimerize olur. </li><li> Yavaş yavaş hücre kültür ortamının 1 ml 3D kültürleri daldırın. <ol><li> Ayrıca jel polimerizasyonu teşvik etmek kuyular içine eklerken medya sıcak olduğundan emin olun. </li><li> KRİTİK ADIM: yavaşça 3D kültürlere medya ekleyebilirsiniz. Kuyulara çok hızlı bir şekilde ortam Pipetleme doku kültürü yüzeyinden 3D kültürlerin ayrılması yol açabilir. </li></ol></li></ol> 3. İzleme ve Sfero Invasion Analizi <ol><li> Araştırmacı tarafından karar zaman noktalarında çevredeki 3D matris içine sferoitlerin Image işgali. 20x objektif lens bir ters mikroskop kullanılarak fotoğraf elde edin. Not: İdeal zaman noktaları test edilen hücre hattı bağlı olarak farklılık gösterecektir. Daha invaziv hücre hatları kısa bir süre sonra kaplama sferoidler kendi dışarı çıkmasını başlar ve bu nedenle, ilk fotoğrafı alacakkaplama sonrası birkaç saat içinde s. Genel olarak, fotoğraf (kaplama) sonra 0 saat, 24 saat ve 48 saat sonra alınmıştır. Invasion genellikle kaplama sonrası 24 saat 48 varmıştır. </li><li> Görüntü J. gibi görüntü analiz yazılımı kullanarak invaziv yeteneklerini ölçmek <ol><li> Sfero kenarından hücre mesafe olarak işgali analiz edin. <ol><li> Yarıçapı ve / veya maksimal invaziv mesafeyi işaretlemek için Düz Beraberlik Aracı&#39;nı kullanın. </li><li> Uzunluk ölçümünü görüntülemek için &quot;Tedbir&quot; üst menüde &quot;Analiz&quot;, ve sonra tıklatın. </li></ol></li><li> Sfero dışında toplam invaziv alanı olarak işgal edilmesi. <ol><li> Sfero ve / veya toplam invaziv alanın sınırını izlemek için Freehand Beraberlik Aracı&#39;nı kullanın. </li><li> Alan ölçümünü görüntülemek için &quot;Tedbir&quot; üst menüde &quot;Analiz&quot;, ve sonra tıklatın. </li></ol></li><li> Görüntülerin bir yığın için ölçümler oluşturmak için ROI Yöneticisi Araçları gibi bir eklenti kullanın. </li></ol>
	</li>
</ol>

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The authors declare that they have no competing financial interests.

Bu çalışma, bir küremsi yayılması deneyinin (Tablo 1) kanser hücre soylarının bir paneli performansını değerlendirildi. Genel olarak, sferoid oluşumu hücre-hücre birleşme varlığı küremsi benzeri mimari oluşumunu teşvik fazla epitelyal dönük hücre hatları, gelişmiş olduğunu fark. MDA-MB-231 hücreleri gibi, bir epitelyal mezenkimal geçiş geçirmiş bilinen hücre hatları, dolayı azaltılmış E-, N- ve P-kadherin ifadesi 16 büyük olasılıkla Asılı damla k?...

Kanser hücre hareketi gibi davranışlar dolaşım sistemi 1 içine bazal membran ve giriş yoluyla işgali kolaylaştırır göz önüne alındığında, metastatik potansiyelin belirleyici olduğu bilinmektedir. Motilite üzerinde en çok araştırma yaygın bir üç boyutlu (3D) matris içinde hücrelerin hareketi olacak aslında nasıl bu aynı hücrelerin daha fazla temsilcisi olduğunu olma yolunda hızla ilerliyor olsa hücreler, iki boyutlu (2D) ayarında nasıl davrandığını odaklanmıştır vivo 2 davranır. 3D kültür sistemleri giderek büyüme kinetikleri ve ilaç duyarlılık 3, hücre morfolojisi değişir hücresel davranışları incelemek için kullanılır. 3D ortamın kapsamında kanser hücre işgali izlemek için arzu 3D hücre dışı içine bu parçacıklarının gömerek ardından asılı damla kültür yöntemiyle 4 aracılığıyla 3D hücre agrega (sferoidler) üretimini kapsayan daha önce kurulmuş tekniklerin sentezine yol açmıştır Matris (ECM) kolajen ve bazal membran malzemelerinin 5 oluşur. Bu yöntem, kolaylıkla deneysel koşullar altında çeşitli işgali karşılaştırma için kullanılabilir akıcı bir yaklaşım sağlayarak bu, daha önce bilinen teknikler geliştirmek için çalışmaktadır. In vitro hücre motilitesini değerlendirmek için daha geleneksel yolları çizilmeye yara tahlil ve transwell tahlil 6 bulunmaktadır. Eski deney 2B ortamda hücre motilitesini tasvir ve in vivo işgali için kritik çeşitli özellikler, örneğin, bir proteaz aktivitesi 7 bağımsızdır. Transwell tahlil de ekler ters membran yüzeyinde hücre görünümü, yani ECM yüzeylerde ancak, yalnızca tek bir parametre ile daha iyi bir model hücre işgali kaplanır zaman ölçülen ve hücre işgali birçok nüanslar böylece kolaylıkla gözlemlenebilir değildirler. Bu teknikler, kanser hücresi sferoid yayılması deneyinin (Şekil 1 &lt;aksine/ strong&gt;) Sadece fizyolojik ilgili olmayan bir ortamda hücre işgali gerçek zamanlı izleme sağlar, fakat aynı zamanda kolektif vs bireysel hücre göçü 8 olarak görüntülenebilir önemli hücre çizgisi özgü özellikleri, izin verir. Bu yöntem aynı zamanda, standart 3D kültürü büyüme tahlilleri fazla avantaj elde edilir. Hücreler bu kısıtlama kaldırdı sonra işgal etmeye teşvik edilecektir böylece asılı damla yöntemi ile hücresel agrega üretimi başlangıçta hücre hareketi kısıtlar. Bu kısıtlama kaldırdı kez Dahası, hücre çıkış sonra uygun quantitated edilebilir bir üniforma yönde devam edecektir. Kanser hücresi sferoidler deneyleri için kullanılan en popüler ECM malzeme Matrigel ve bu bileşenlerin her biri metastatik davranışını etkileyen önemli ve farklı rolleri vardır burada tip I, hücre oranında yerleştirilmiştir. Matrigel Engelbreth-Holm Swarm fare sarkoma hücreleri tarafından üretilen proteinlerin salgılanan karışımıdır ve baseme içinde zenginleştirilmiş olanBöyle laminin, Entactin ve tip IV kollajen 9 olarak nt zar proteinleri. Bu nedenle, Matrigel bundan böyle adlandırılır &quot;bazal membran malzemeler&quot;. Bu bazal zar malzemeleri hücre davranışı 11 üzerindeki etkileri bir dizi gösterirler sayıdaki başka protein ek olarak, kanser hücresi yayılımını tamamen 10 boyunca yapışma integrin için gerekli temel ligandı sunar. Buna karşılık, genellikle tendon ve diğer yoğun kollajen yapılar 12 asit sindirimleri hazırlanabilir I kolajen türü, vücut bağ dokusu ve stromanın destekleyici dokuların ve organların büyük bir yapısal elemanı olarak hizmet eden daha basit bir dolgu maddesi. Bu kollajen fiziksel özellikleri, hücre motilitesinin bir dizi özellik düzenleyen ortaya konmuştur; örneğin tümör-stroma arayüzünde kolajen fibrilleri hizalama stroma 13 içine işgalci, sonradan bu fibriller boyunca geçirmek için kanser hücrelerinin izin verir. Burada yer alan deneyinde, hem tip I kolajen ve bazal zar malzemeleri 3D kanser hücresi-stroma etkileşimleri incelemek için bir araç olarak kullanılır. Hücreler 3 boyutlu bir matris içine gömülü edildikten sonra işgal izlenebilir kontrol yollarının engellenmesi veya stimülasyon etkisi. Hücreler, asılı damla ya da uzun bir işleme işgali modüle etmek için gerekli olacaktır bağlı olarak 3D kültür, transfer üzerine büyüme sırasında ön muameleye tabi tutulabilir. Kısa tedaviler için, ilacın alımından sonra küremsi süspansiyon, hem de hücrelere yeterli ilaç maruziyeti kolaylaştırmak için, 3D kültürleri saracak ortamı ile karıştırılabilir önerilir. Daha sonra, normal veya tümör bağlantılı stromal hücreleri, tümör hücresi istilasını modüle edilmesinde rolünü değerlendirmek için, ya da ne kadar parakrin ve otokrin sinyal etkiler, hücre davranışını tespit etmek matris malzemesi ile karıştırılabilmektedir. Bu fikir bir çalışmada gösterilmiştir nerede col Coculturekanser ve asılı damla endotelyal hücreler üzerinde sferoidler 14 içinde damar ağı yol açtı. Kanser hücre istilası farklı alt-tabaka 15 tarafından temas edilmesinin Son olarak, ECM bileşenleri, aynı zamanda, değiştirilebilir. Aşağıda sunulan durumda, yöntem, çeşitli koşullar altında kanser hücresi invazyonunu değerlendirilmesi için bir çerçeve sağlar. Genel olarak, tüm hücre kuşakları asılı damla parçacıklarının yaratacak ve epitel dönük hücre hatları genellikle, normal küre formunda olduğu belirlendi.

<table>
	<tbody>
		<tr>
			<td>Matrigel Growth Factor Reduced</td>
			<td>Corning</td>
			<td>CB-40234</td>
			<td></td>
		</tr>
		<tr>
			<td>Collagen Type I, Rat Tail, 100 mg</td>
			<td>Millipore</td>
			<td>08-115</td>
			<td></td>
		</tr>
		<tr>
			<td>DMEM</td>
			<td>Life Technologies</td>
			<td>11995-065</td>
			<td></td>
		</tr>
		<tr>
			<td>RPMI 1640 Medium&#160;</td>
			<td>Life Technologies</td>
			<td>11875-093</td>
			<td></td>
		</tr>
		<tr>
			<td>PBS</td>
			<td>Life Technologies</td>
			<td>10010-023</td>
			<td></td>
		</tr>
		<tr>
			<td>0.05% Trypsin-EDTA</td>
			<td>Life Technologies</td>
			<td>25300-054</td>
			<td></td>
		</tr>
		<tr>
			<td>Fetal Bovine Serum, Heat Inactivated</td>
			<td>Omega Scientific</td>
			<td>FB-12</td>
			<td></td>
		</tr>
		<tr>
			<td>100mm TC-treated Dishes</td>
			<td>Corning Incorporated</td>
			<td>430167</td>
			<td></td>
		</tr>
		<tr>
			<td>24-well TC-treated Plates</td>
			<td>NEST Biotechnlology</td>
			<td>702001</td>
			<td></td>
		</tr>
		<tr>
			<td>Olympus IX-71 Inverted Microscope</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td colspan="4">Cell lines were maintained in DMEM + 10% FBS, with the expection of BT-474 and LNCaP cells, which were mantained in RPMI + 10% FBS.</td>
		</tr>
	</tbody>
</table>

a cancer cell spheroid assay to assess invasion in a 3d setting

The invasive nature of cancer cell lines is thought to correlate with their metastatic potential. Most traditional assays, however, do not examine these invasive features in a three-dimensional environment and the resulting data suffer from reduced biological applicability. Here an approach is presented to visualize the invasive ability of cell lines in a physiologically relevant setting. The cancer cell spheroid invasion assay first utilizes gravity to generate spheroids within drops of media that hang from the lid of a cell culture dish. Next, these spheroids are embedded in a 3D matrix consisting of a mixture of basement membrane materials and type I collagen. Cancer cell egression from the spheroids into the surrounding matrix is then monitored over time. The method described here can be modified to examine invasion after coculture of different cell types, inclusion of drugs/inhibitors, or alterations in extracellular matrix (ECM) constituents.

Sferoid invazyon testi kullanılarak (Şekil 1), kanser hücre soylarının bir paneli, hem de bazal membran malzemeleri ve tip I kolajen oluşan 3 boyutlu bir matris içinde implantasyon sonrası sergilenen hücre egress miktarı için küreler oluşturma kabiliyetleri için test edildi (Tablo 1). Bu sonuçlar, her kanser hücre çizgisi, in vitro olarak bir epitel morfolojisi sahip hücre çizgileri düzenli ve düzgün agrega üretme eğilimindeydi iyi biçimli sferoidler, y...

Watch this Scientific Journal Video about A Cancer Cell Spheroid Assay to Assess Invasion in a 3D Setting at JoVE.com

A Cancer Cell Spheroid Assay to Assess Invasion in a 3D Setting

This method evaluates cancer cell invasion from spheroids into a surrounding 3D matrix. Spheroids are generated via the hanging drop culture method and then embedded in a matrix comprised of basement membrane materials and type I collagen. Invasion out of the spheroids is subsequently monitored.

Bir Kanseri Hücre Sfero Testi 3D ortamda Invasion Değerlendirmek için

The invasive nature of cancer cell lines is thought to correlate with their metastatic potential.  Most traditional assays, however, do not examine these ...

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32.3K Görüntüleme.  Georgetown University. This method evaluates cancer cell invasion from spheroids into a surrounding 3D matrix. Spheroids are generated via the hanging drop culture method and then embedded in a matrix comprised of basement membrane materials and type I collagen. Invasion out of the spheroids is subsequently monitored. 

Video: A Cancer Cell Spheroid Assay to Assess Invasion in a 3D Setting

A Real-time Electrical Impedance Based Technique to Measure Invasion of Endothelial Cell Monolayer by Cancer Cells

Metastatic dissemination of malignant cells requires degradation of basement membrane, attachment of tumor cells to vascular endothelium, retraction of endothelial junctions and finally invasion and migration of tumor cells through the endothelial layer to enter the bloodstream as a means of transport to distant sites in the host1-3. Once in the circulatory system, cancer cells adhere to capillary walls and extravasate to the surrounding tissue to form metastatic tumors4,5. The various components of tumor cell-endothelial cell interaction can be replicated in vitro by challenging a monolayer of human umbilical vein endothelial cells (HUVEC) with cancer cells. Studies performed with electron and phase-contrast microscopy suggest that the in vitro sequence of events fairly represent the in vivo metastatic process6. Here, we describe an electrical-impedance based technique that monitors and quantifies in real-time the invasion of endothelial cells by malignant tumor cells.
Giaever and Keese first described a technique for measuring fluctuations in impedance when a population of cells grow on the surface of electrodes7,8. The xCELLigence instrument, manufactured by Roche, utilizes a similar technique to measure changes in electrical impedance as cells attach and spread in a culture dish covered with a gold microelectrode array that covers approximately 80% of the area on the bottom of a well. As cells attach and spread on the electrode surface, it leads to an increase in electrical impedance9-12. The impedance is displayed as a dimensionless parameter termed cell-index, which is directly proportional to the total area of tissue-culture well that is covered by cells. Hence, the cell-index can be used to monitor cell adhesion, spreading, morphology and cell density.
The invasion assay described in this article is based on changes in electrical impedance at the electrode/cell interphase, as a population of malignant cells invade through a HUVEC monolayer (Figure 1). The disruption of endothelial junctions, retraction of endothelial monolayer and replacement by tumor cells lead to large changes in impedance. These changes directly correlate with the invasive capacity of tumor cells, i.e., invasion by highly aggressive cells lead to large changes in cell impedance and vice versa. This technique provides a two-fold advantage over existing methods of measuring invasion, such as boyden chamber and matrigel assays: 1) the endothelial cell-tumor cell interaction more closely mimics the in vivo process, and 2) the data is obtained in real-time and is more easily quantifiable, as opposed to end-point analysis for other methods.

This article describes an in vitro technique for monitoring cancer cells invading through a monolayer of endothelial cells. The data is acquired in real-time as a function of changes in impedance on the surface of electrodes at the well bottom.

Kanser Hücreleri Endotel Hücre Tek tabakalı Invasion Tedbir Gerçek zamanlı Elektrik Empedans Tabanlı Tekniği

Metastatic dissemination of malignant cells requires degradation of basement membrane, attachment of tumor cells to vascular endothelium, retraction of ...

Tıp

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.

Oral Skuamöz Hücre Karsinomu Ortotopik Fare Modeli Tümör Hücre Invasion Multi-foton Görüntüleme

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

Spheroid Assay to Measure TGF-&#946;-induced Invasion

TGF-&beta; has opposing roles in breast cancer progression by acting as a tumor suppressor in the initial phase, but stimulating invasion and metastasis at later stage1,2. Moreover, TGF-&beta; is frequently overexpressed in breast cancer and its expression correlates with poor prognosis and metastasis 3,4. The mechanisms by which TGF-&beta; induces invasion are not well understood.
TGF-&beta; elicits its cellular responses via TGF-&beta; type II (T&beta;RII) and type I (T&beta;RI) receptors. Upon TGF-&beta;-induced heteromeric complex formation, T&beta;RII phosphorylates the T&beta;RI. The activated T&beta;RI initiates its intracellular canonical signaling pathway by phosphorylating receptor Smads (R-Smads), i.e. Smad2 and Smad3. These activated R-Smads form heteromeric complexes with Smad4, which accumulate in the nucleus and regulate the transcription of target genes5. In addition to the previously described Smad pathway, receptor activation results in activation of several other non-Smad signaling pathways, for example Mitogen Activated Protein Kinase (MAPK) pathways6.
To study the role of TGF-&beta; in different stages of breast cancer, we made use of the MCF10A cell system. This system consists of spontaneously immortalized MCF10A1 (M1) breast epithelial cells7, the H-RAS transformed M1-derivative MCF10AneoT (M2), which produces premalignant lesions in mice8, and the M2-derivative MCF10CA1a (M4), which was established from M2 xenografts and forms high grade carcinomas with the ability to metastasize to the lung9. This MCF10A series offers the possibility to study the responses of cells with different grades of malignancy that are not biased by a different genetic background.
For the analysis of TGF-&beta;-induced invasion, we generated homotypic MCF10A spheroid cell cultures embedded in a 3D collagen matrix in vitro (Fig 1). Such models closely resemble human tumors in vivo by establishing a gradient of oxygen and nutrients, resulting in active and invasive cells on the outside and quiescent or even necrotic cells in the inside of the spheroid10. Spheroid based assays have also been shown to better recapitulate drug resistance than monolayer cultures11. This MCF10 3D model system allowed us to investigate the impact of TGF-&beta; signaling on the invasive properties of breast cells in different stages of malignancy.

Spheroid Assay to Measure TGF-&amp;#946;-induced Invasion

An assay to quantitatively measure Transforming Growth Factor (TGF)-&#x03B2;-induced invasion in 3-dimensional collagen gels is described. This assay takes advantage of the MCF10A series of cell lines, which represent different stages of breast cancer development. This method can be adopted to be used with other cell lines and might be used to investigate other potential activators or inhibitors of invasion.

TGF-β-kaynaklı Invasion Tedbir Sfero Testi

TGF-&beta; has opposing roles in breast cancer progression by acting as a tumor suppressor in the initial phase, but stimulating invasion and metastasis ...

Modeling and Imaging 3-Dimensional Collective Cell Invasion

A defining characteristic of cancer malignancy is invasion and metastasis 1. In some cancers (e.g. glioma 2), local invasion into surrounding healthy tissue is the root cause of disease and death. For other cancers (e.g. breast, lung, etc.), it is the process of metastasis, in which tumor cells move from a primary tumor mass, colonize distal sites and ultimately contribute to organ failure, that eventually leads to morbidity and mortality 3. It has been estimated that invasion and metastasis are responsible for 90&#37; of cancer deaths 4. As a result, there has been intense interest in identifying the molecular processes and critical protein mediators of invasion and metastasis for the purposes of improving diagnosis and treatment 5.
A challenge for cancer scientists is to develop invasion assays that sufficiently resemble the in vivo situation to enable accurate disease modeling 6. Two-dimensional cell motility assays are only informative about one aspect of invasion and do not take into account extracellular matrix (ECM) protein remodeling which is also a critical element. Recently, research has refined our understanding of tumor cell invasion and revealed that individual cells may move by elongated or rounded modes 7. In addition, there has been greater appreciation of the contribution of collective invasion, in which cells invade in strands, sheets and clusters, particularly in highly differentiated tumors that maintain epithelial characteristics, to the spread of cancer 8.
We present a refined method 9 for examining the contributions of candidate proteins to collective invasion 10. In particular, by engineering separate pools of cells to express different fluorescent proteins, it is possible to molecularly dissect the activities and proteins required in leading cells versus those required in following cells. The use of RNAi provides the molecular tool to experimentally disassemble the processes involved in individual cell invasion as well as in different positions of collective invasion. In this procedure, mixtures of fluorescently-labeled cells are plated on the bottom of a Transwell insert previously filled with Matrigel ECM protein, then allowed to invade "upwards" through the filter and into the Matrigel. Reconstruction of z-series image stacks, obtained by confocal imaging, into three-dimensional representations allows for visualization of collectively invading strands and analysis of the representation of fluorescently-labeled cells in leading versus following positions.

Models of tumor cell invasion into three-dimensional extracellular matrix better reflect the in vivo situation than two-dimensional motility assays. Using matrix invasion assays combined with confocal imaging of fluorescently-labeled cells, detailed information on invasion modes and the distinct contributions of leading versus following cells can be obtained.

Modelleme ve Görüntüleme 3-Boyutlu Toplu Hücre Invasion

A defining characteristic of cancer malignancy is invasion and metastasis 1. In some cancers (e.g. glioma 2), local invasion into surrounding healthy ...

In vitro Mesothelial Clearance Assay that Models the Early Steps of Ovarian Cancer Metastasis

Ovarian cancer is the fifth leading cause of cancer related deaths in the United States1. Despite a positive initial response to therapies, 70 to 90 percent of women with ovarian cancer develop new metastases, and the recurrence is often fatal2. It is, therefore, necessary to understand how secondary metastases arise in order to develop better treatments for intermediate and late stage ovarian cancer. Ovarian cancer metastasis occurs when malignant cells detach from the primary tumor site and disseminate throughout the peritoneal cavity. The disseminated cells can form multicellular clusters, or spheroids, that will either remain unattached, or implant onto organs within the peritoneal cavity3 (Figure 1, Movie 1). 
All of the organs within the peritoneal cavity are lined with a single, continuous, layer of mesothelial cells4-6 (Figure 2). However, mesothelial cells are absent from underneath peritoneal tumor masses, as revealed by electron micrograph studies of excised human tumor tissue sections3,5-7 (Figure 2). This suggests that mesothelial cells are excluded from underneath the tumor mass by an unknown process. 
Previous in vitro experiments demonstrated that primary ovarian cancer cells attach more efficiently to extracellular matrix than to mesothelial cells8, and more recent studies showed that primary peritoneal mesothelial cells actually provide a barrier to ovarian cancer cell adhesion and invasion (as compared to adhesion and invasion on substrates that were not covered with mesothelial cells)9,10. This would suggest that mesothelial cells act as a barrier against ovarian cancer metastasis. The cellular and molecular mechanisms by which ovarian cancer cells breach this barrier, and exclude the mesothelium have, until recently, remained unknown. 
Here we describe the methodology for an in vitro assay that models the interaction between ovarian cancer cell spheroids and mesothelial cells in vivo (Figure 3, Movie 2). Our protocol was adapted from previously described methods for analyzing ovarian tumor cell interactions with mesothelial monolayers8-16, and was first described in a report showing that ovarian tumor cells utilize an integrin &#x2013;dependent activation of myosin and traction force to promote the exclusion of the mesothelial cells from under a tumor spheroid17. This model takes advantage of time-lapse fluorescence microscopy to monitor the two cell populations in real time, providing spatial and temporal information on the interaction. The ovarian cancer cells express red fluorescent protein (RFP) while the mesothelial cells express green fluorescent protein (GFP). RFP-expressing ovarian cancer cell spheroids attach to the GFP-expressing mesothelial monolayer. The spheroids spread, invade, and force the mesothelial cells aside creating a hole in the monolayer. This hole is visualized as the negative space (black) in the GFP image. The area of the hole can then be measured to quantitatively analyze differences in clearance activity between control and experimental populations of ovarian cancer and/ or mesothelial cells. This assay requires only a small number of ovarian cancer cells (100 cells per spheroid X 20-30 spheroids per condition), so it is feasible to perform this assay using precious primary tumor cell samples. Furthermore, this assay can be easily adapted for high throughput screening.

In vitro Mesothelial Clearance Assay that Models the Early Steps of Ovarian Cancer Metastasis

The mesothelial clearance assay described here takes advantage of fluorescently labeled cells and time-lapse video microscopy to visualize and quantitatively measure the interactions of ovarian cancer multicellular spheroids and mesothelial cell monolayers. This assay models the early steps of ovarian cancer metastasis.

In vitro Mezotelyal Gümrükleme Assay o Yumurtalık Kanseri Metastaz Erken Adımlar modeller

Ovarian cancer is the fifth leading cause of cancer related deaths in the United States1. Despite a positive initial response to therapies, 70 to 90 ...

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.

Üç boyutlu (3D) Modeli Kullanılarak Meme Kanseri Hücre invazivliğinin Kantitasyonu

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

A Modified In vitro Invasion Assay to Determine the Potential Role of Hormones, Cytokines and/or Growth Factors in Mediating Cancer Cell Invasion

Blood serum serves as a chemoattractant towards which cancer cells migrate and invade, facilitating their intravasation into microvessels. However, the actual molecules towards which the cells migrate remain elusive. This modified invasion assay has been developed to identify targets which drive cell migration and invasion. This technique compares the invasion index under three conditions to determine whether a specific hormone, growth factor, or cytokine plays a role in mediating the invasive potential of a cancer cell. These conditions include i) normal fetal bovine serum (FBS), ii) charcoal-stripped FBS (CS-FBS), which removes hormones, growth factors, and cytokines and iii) CS-FBS + molecule (denoted &#8220;X&#8221;). A significant change in cell invasion with CS-FBS as compared to FBS, indicates the involvement of hormones, cytokines or growth factors in mediating the change. Individual molecules can then be added back to CS-FBS to assay their ability to reverse or rescue the invasion phenotype. Furthermore, two or more factors can be combined to evaluate the additive or synergistic effects of multiple molecules in driving or inhibiting invasion. Overall, this method enables the investigator to determine whether hormones, cytokines, and/or growth factors play a role in cell invasion by serving as chemoattractants or inhibitors of invasion for a particular type of cancer cell or a specific mutant. By identifying specific chemoattractants and inhibitors, this modified invasion assay may help to elucidate signaling pathways that direct cancer cell invasion.

A Modified In vitro Invasion Assay to Determine the Potential Role of Hormones, Cytokines and/or Growth Factors in Mediating Cancer Cell Invasion

This video article describes a modified in vitro method to examine the role of hormones, cytokines and/or growth factors in driving cancer cell invasion.

Bir Modifiye<em&gt; In vitro</em&gt; Invasion Deneyi Hormonlar, Açan Kanser Hücre Invasion Sitokinlerin ve / veya Büyüme Faktörleri Potansiyel Rolü belirlemek için

Blood serum serves as a chemoattractant towards which cancer cells migrate and invade, facilitating their intravasation into microvessels. However, the ...

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.

Real Time Mezotelyal Hücrelerinin Yumurtalık Kanseri Sferoid Ek ve Invasion Değerlendirilmesi

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

Focus Formation: A Cell-based Assay to Determine the Oncogenic Potential of a Gene

Malignant transformation of cells is typically associated with increased proliferation, loss of contact inhibition, acquisition of anchorage-independent growth potential, and the ability to form tumors in experimental animals1. In NIH 3T3 cells, the Ras signal transduction pathway is known to trigger many of these events, what is known as Ras transformation. The introduction of an overexpressed gene in NIH 3T3 cells may promote morphological transformation and loss of contact inhibition, which can help determine the oncogenic potential of that gene of interest. An assay that provides a straightforward method to assess one aspect of the transforming potential of an oncogene is the Focus Formation Assay (FFA)2. When NIH 3T3 cells divide normally in culture, they do so until they reach a confluent monolayer. However, in the presence of an overexpressed oncogene, these cells can begin to grow in dense, multilayered foci1 that can be visualized and quantified by crystal violet or Hema 3 staining. In this article we describe the FFA protocol with retroviral transduction of the gene of interest into NIH 3T3 cells, and how to quantify the number of foci through staining. Retroviral transduction offers a more efficient method of gene delivery than transfection, and the use of an ecotropic murine retrovirus provides a biosafety control when working with potential human oncogenes.

The Focus Formation Assay provides a straightforward method to assess the transforming potential of a candidate oncogene.

Formation Odak: bir hücreye dayalı tahlil, bir genin onkojenik potansiyeli belirlemek için

Malignant transformation of cells is typically associated with increased proliferation, loss of contact inhibition, acquisition of anchorage-independent ...

Carotid Artery Infusions for Pharmacokinetic and Pharmacodynamic Analysis of Taxanes in Mice

When proposing the use of a drug, drug combination, or drug delivery into a novel system, one must assess the pharmacokinetics of the drug in the study model. As the use of mouse models are often a vital step in preclinical drug discovery and drug development1-8, it is necessary to design a system to introduce drugs into mice in a uniform, reproducible manner. Ideally, the system should permit the collection of blood samples at regular intervals over a set time course. The ability to measure drug concentrations by mass-spectrometry, has allowed investigators to follow the changes in plasma drug levels over time in individual mice1, 9, 10. In this study, paclitaxel was introduced into transgenic mice as a continuous arterial infusion over three hours, while blood samples were simultaneously taken by retro-orbital bleeds at set time points. Carotid artery infusions are a potential alternative to jugular vein infusions, when factors such as mammary tumors or other obstructions make jugular infusions impractical. Using this technique, paclitaxel concentrations in plasma and tissue achieved similar levels as compared to jugular infusion. In this tutorial, we will demonstrate how to successfully catheterize the carotid artery by preparing an optimized catheter for the individual mouse model, then show how to insert and secure the catheter into the mouse carotid artery, thread the end of the catheter out through the back of the mouse&#8217;s neck, and hook the mouse to a pump to deliver a controlled rate of drug influx. Multiple low volume retro-orbital bleeds allow for analysis of plasma drug concentrations over time.

This method was developed with the goal of delivering a steady drug solution via the carotid artery, to assess the pharmacokinetics of novel drugs in mouse models.

Farelerde Taksanlar Farmakokinetik ve Farmakodinamik Analiz Karotis Arter İnfüzyonlar

When proposing the use of a drug, drug combination, or drug delivery into a novel system, one must assess the pharmacokinetics of the drug in the study ...