Wir danken den Mitgliedern unseres Labors für ihre hilfreichen Gespräche und Unterstützung. Unsere Forschung zu Brustkrebsstammzellen und der Tumormikroumgebung wird durch Zuschüsse des Canadian Cancer Research Society Research Institute und des Brustkrebsprogramms des US-Verteidigungsministeriums (Grant # BC160912) finanziert. V.B. wird durch ein Western Postdoctoral Fellowship (Western University) unterstützt, und sowohl A.L.A. als auch V.B. werden von der Breast Cancer Society of Canada unterstützt. C.L. wird durch ein Vanier Canada Graduate Scholarship der kanadischen Regierung unterstützt.

Die Autoren haben nichts offenzulegen.

Brustkrebsmetastasen und Therapieresistenzen sind weltweit zu einer Haupttodesursache bei Frauen geworden. Die Existenz einer Subpopulation von Brustkrebsstammzellen (BCSCs) trägt zur verstärkten Metastasierung 26,43,44,45,46 und Therapieresistenz21,47,48 bei. Daher...

Das Verständnis der zellulären und molekularen Mechanismen menschlicher Brustkrebsstammzellen (BCSCs) ist entscheidend, um die Herausforderungen bei der Brustkrebsbehandlung zu bewältigen. Die Entstehung des BCSC-Konzepts geht auf das frühe 21. Jahrhundert zurück, als eine kleine Population von CD44+CD24-/niedrigen Brustkrebszellen in der Lage war, heterogene Tumore in Mäusen zu erzeugen 1,2. Anschließend wurde beobachtet, dass menschliche Brustkrebszellen mit hoher enzymatischer Aktivität der Aldehyddehydrogenase (ALDHhigh) ebenfalls ähnliche stammzellähnliche Eigenschaften aufwiesen3. Diese BCSCs stellen eine kleine Population von Zellen dar, die zur Selbsterneuerung und Differenzierung fähig sind, was zur heterogenen Natur von Massentumoren beiträgt 1,2,3. Zunehmende Beweise deuten darauf hin, dass Veränderungen in evolutionär konservierten Signalwegen das Überleben und die Aufrechterhaltung von BCSC vorantreiben 4,5,6,7,8,9,10,11,12,13,14 . Darüber hinaus hat sich gezeigt, dass die extrinsische Mikroumgebung der Zelle eine entscheidende Rolle bei der Bestimmung verschiedener BCSC-Funktionen spielt15,16,17. Diese molekularen Signalwege und die externen Faktoren, die die BCSC-Funktion regulieren, tragen zum Rückfall von Brustkrebs, zur Metastasierung18 und zur Entwicklung von Therapieresistenzen bei 19,20,21, wobei die Restexistenz von BCSCs nach der Behandlung eine große Herausforderung für das Gesamtüberleben von Brustkrebspatientinnen darstellt22,23 . Die präklinische Bewertung dieser Faktoren ist daher sehr wichtig, um BCSC-zielgerichtete Therapien zu identifizieren, die für bessere Behandlungsergebnisse und ein verbessertes Gesamtüberleben bei Brustkrebspatientinnen von Vorteil sein könnten.
Mehrere in vitro menschliche Brustkrebs-Zelllinienmodelle und in vivo menschliche Xenograft-Modelle wurden verwendet, um BCSCs 24,25,26,27,28,29 zu charakterisieren. Die Fähigkeit von Zelllinien, sich nach jeder nachfolgenden Passage kontinuierlich neu zu besiedeln, macht diese zu einem idealen Modellsystem für die Durchführung von Omics-basierten und pharmakogenomischen Studien. Zelllinien können jedoch die in Patientenproben beobachtete Heterogenität oft nicht rekapitulieren. Daher ist es wichtig, Zellliniendaten mit Patientenproben zu ergänzen. Die Isolierung von BCSCs in ihrer reinsten Form ist wichtig, um eine detaillierte Charakterisierung von BCSCs zu ermöglichen. Das Erreichen dieser Reinheit hängt von der Auswahl der phänotypischen Marker ab, die für BCSCs spezifisch sind. Derzeit wird der ALDH-Zellphänotypmit hohemCD44+CD24-Zellgehalt am häufigsten verwendet, um humane BCSCs aus Massen-Brustkrebszellpopulationen zu unterscheiden und zu isolieren, wobei Fluoreszenz-aktivierte Zellsortierung (FACS) für maximale Reinheit verwendet wird 1, 3,26. Darüber hinaus können die Eigenschaften isolierter BCSCs wie Selbsterneuerung, Proliferation und Differenzierung mit in vitro und in vivo Techniken bewertet werden.
Zum Beispiel können In-vitro-Koloniebildungsassays verwendet werden, um die Fähigkeit einer einzelnen Zelle zu beurteilen, sich selbst zu erneuern, um eine Kolonie von 50 Zellen oder mehr bei unterschiedlichen Behandlungsbedingungen zu bilden30. Mammosphären-Assays können auch verwendet werden, um das Selbsterneuerungspotenzial von Brustkrebszellen unter verankerten Bedingungen zu beurteilen. Dieser Assay misst die Fähigkeit einzelner Zellen, bei jeder nachfolgenden Passage unter serumfreien, nicht adhärenten Kulturbedingungen als Kugeln (Mischung aus BCSCs und Nicht-BCSCs) zu erzeugen und zu wachsen31. Darüber hinaus können 3-dimensionale (3D) Kulturmodelle verwendet werden, um die BCSC-Funktion zu bewerten, einschließlich Zell-Zell- und Zell-Matrix-Interaktionen, die die In-vivo-Mikroumgebung genau rekapitulieren und die Untersuchung der Aktivität potenzieller BCSC-zielgerichteter Therapien ermöglichen32. Trotz der vielfältigen Anwendungen von In-vitro-Modellen ist es schwierig, die Komplexität von In-vivo-Bedingungen nur mit In-vitro-Assays zu modellieren. Diese Herausforderung kann durch die Verwendung von Maus-Xenograft-Modellen zur Bewertung des BCSC-Verhaltens in vivo überwunden werden. Insbesondere dienen solche Modelle als ideales System zur Beurteilung der Brustkrebsmetastasierung33, zur Untersuchung von Wechselwirkungen mit der Mikroumgebung während des Krankheitsverlaufs 34, zur In-vivo-Bildgebung 35 und zur Vorhersage der patientenspezifischen Toxizität und Wirksamkeit von Antitumorwirkstoffen 34.
Dieses Protokoll bietet eine detaillierte Beschreibung für die Isolierung von humanen ALDHhohenCD44+CD24- BCSCs in maximaler Reinheit aus Massenpopulationen heterogener Brustkrebszellen. Wir bieten auch eine detaillierte Beschreibung von drei In-vitro-Techniken (koloniebildender Assay, Mammosphärentest und 3D-Kulturmodell) und einen In-vivo-Tumor-Xenograft-Assay, der zur Beurteilung verschiedener Funktionen von BCSCs verwendet werden kann. Diese Methoden wären für Forscher geeignet, die an der Isolierung und Charakterisierung von BCSCs aus menschlichen Brustkrebszelllinien oder primär von Patienten abgeleiteten Brustkrebszellen und Tumorgewebe interessiert sind, um die BCSC-Biologie zu verstehen und/oder neuartige BCSC-zielgerichtete Therapien zu untersuchen.

<table>
	<tbody>
		<tr>
			<td>7-Aminoactinomycin D (7AAD)</td>
			<td>BD</td>
			<td>51-68981E</td>
			<td>suggested: 0.25 &#181;g/1x106 cells</td>
		</tr>
		<tr>
			<td>Acetone</td>
			<td>Fisher</td>
			<td>A18-1</td>
			<td></td>
		</tr>
		<tr>
			<td>Aldehyde dehydrogenase (ALDH) substrate</td>
			<td>Stemcell Technologies</td>
			<td>1700</td>
			<td>Sold commerically as part of the ALDEFLOUR Assay kit; follow manufacturer&#39;s instructions for ALDH substrate preparation</td>
		</tr>
		<tr>
			<td>Basement membrane extract (BME)</td>
			<td>Corning</td>
			<td>354234</td>
			<td>Sold under the commercial name Matrigel</td>
		</tr>
		<tr>
			<td>Cell culture plates: 6 well</td>
			<td>Corning</td>
			<td>877218</td>
			<td></td>
		</tr>
		<tr>
			<td>Cell culture plates: 60mm</td>
			<td>Corning</td>
			<td>353002</td>
			<td></td>
		</tr>
		<tr>
			<td>Cell culture plates: 96-well ultra low attachment</td>
			<td>Corning</td>
			<td>3474</td>
			<td></td>
		</tr>
		<tr>
			<td>Cell strainer: 40 micron</td>
			<td>BD</td>
			<td>352340</td>
			<td></td>
		</tr>
		<tr>
			<td>Collagen</td>
			<td>Stemcell Technologies</td>
			<td>7001</td>
			<td>Prepare 1:30 dilution of 3 mg/mL collagen in PBS</td>
		</tr>
		<tr>
			<td>Collagenase</td>
			<td>Sigma</td>
			<td>11088807001</td>
			<td>1x</td>
		</tr>
		<tr>
			<td>Conical tubes: 50 mL</td>
			<td>Fisher scientific</td>
			<td>05-539-7</td>
			<td></td>
		</tr>
		<tr>
			<td>Crystal violet</td>
			<td>Sigma</td>
			<td>C6158</td>
			<td>Use 0.05% crystal violet solution in water for staining</td>
		</tr>
		<tr>
			<td>Dispase</td>
			<td>Stemcell Technologies</td>
			<td>7913</td>
			<td>5U/mL</td>
		</tr>
		<tr>
			<td>DMEM:F12</td>
			<td>Gibco</td>
			<td>11330-032</td>
			<td>1x, With L-glutamine and 15 mM HEPES</td>
		</tr>
		<tr>
			<td>DNAse</td>
			<td>Sigma</td>
			<td>D5052</td>
			<td>0.1 mg/mL final concentration</td>
		</tr>
		<tr>
			<td>FBS</td>
			<td>Avantor Seradigm Lifescience</td>
			<td>97068-085</td>
			<td>&#160;</td>
		</tr>
		<tr>
			<td>Flow tubes: 5ml</td>
			<td>BD</td>
			<td>352063</td>
			<td>Polypropylene round-bottom tubes</td>
		</tr>
		<tr>
			<td>Methanol</td>
			<td>Fisher</td>
			<td>84124</td>
			<td></td>
		</tr>
		<tr>
			<td>mouse anti-Human CD24 antibody</td>
			<td>BD</td>
			<td>561646</td>
			<td>R-phycoerythrin and Cyanine dye conjugated Clone: ML5</td>
		</tr>
		<tr>
			<td>mouse anti-Human CD44 antibody</td>
			<td>BD</td>
			<td>555479</td>
			<td>R-phycoerythrin conjugated, Clone: G44-26</td>
		</tr>
		<tr>
			<td>N,N-diethylaminobenzaldehyde (DEAB)</td>
			<td>Stemcell Technologies</td>
			<td>1700</td>
			<td>Sold commerically as part of the ALDEFLOUR Assay kit; follow manufacturer&#39;s instructions DEAB preparation</td>
		</tr>
		<tr>
			<td>PBS</td>
			<td>Wisent Inc</td>
			<td>311-425-CL</td>
			<td>1x, Without calcium and magnesium</td>
		</tr>
		<tr>
			<td>Trypsin-EDTA</td>
			<td>Gibco</td>
			<td>25200-056</td>
			<td></td>
		</tr>
		<tr>
			<td></td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Mammosphere Media Composition</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>B27</td>
			<td>Gibco</td>
			<td>17504-44</td>
			<td>1x</td>
		</tr>
		<tr>
			<td>bFGF</td>
			<td>Sigma</td>
			<td>F2006</td>
			<td>10 ng/mL</td>
		</tr>
		<tr>
			<td>BSA</td>
			<td>Bioshop</td>
			<td>ALB003</td>
			<td>04%</td>
		</tr>
		<tr>
			<td>DMEM:F12</td>
			<td>Gibco</td>
			<td>11330-032</td>
			<td>1x, With L-glutamine and 15 mM HEPES</td>
		</tr>
		<tr>
			<td>EGF</td>
			<td>Sigma</td>
			<td>E9644</td>
			<td>20 ng/mL</td>
		</tr>
		<tr>
			<td>Insulin</td>
			<td>Sigma</td>
			<td>16634</td>
			<td>5 &#181;g/mL</td>
		</tr>
		<tr>
			<td></td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>3D Organoid Media Composition</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>A8301</td>
			<td>Tocris</td>
			<td>2939</td>
			<td>500 nM</td>
		</tr>
		<tr>
			<td>B27</td>
			<td>Gibco</td>
			<td>17504-44</td>
			<td>1x</td>
		</tr>
		<tr>
			<td>DMEM:F12</td>
			<td>Gibco</td>
			<td>11330-032</td>
			<td>1x, With L-glutamine and 15 mM HEPES</td>
		</tr>
		<tr>
			<td>EGF</td>
			<td>Sigma</td>
			<td>E9644</td>
			<td>5 ng/mL</td>
		</tr>
		<tr>
			<td>FGF10</td>
			<td>Peprotech</td>
			<td>100-26</td>
			<td>20 ng/mL</td>
		</tr>
		<tr>
			<td>FGF7</td>
			<td>Peprotech</td>
			<td>100-19</td>
			<td>5 ng/mL</td>
		</tr>
		<tr>
			<td>GlutaMax</td>
			<td>Invitrogen</td>
			<td>35050-061</td>
			<td>1x</td>
		</tr>
		<tr>
			<td>HEPES</td>
			<td>Gibco</td>
			<td>15630-080</td>
			<td>10 mM</td>
		</tr>
		<tr>
			<td>N-acetylcysteine</td>
			<td>Sigma</td>
			<td>A9165</td>
			<td>1.25 mM</td>
		</tr>
		<tr>
			<td>Neuregulin &#946;1</td>
			<td>Peprotech</td>
			<td>100-03</td>
			<td>5 nM</td>
		</tr>
		<tr>
			<td>Nicotinamide</td>
			<td>Sigma</td>
			<td>N0636</td>
			<td>5 mM</td>
		</tr>
		<tr>
			<td>Noggin</td>
			<td>Peprotech</td>
			<td>120-10C</td>
			<td>100 ng/mL</td>
		</tr>
		<tr>
			<td>R-spondin3</td>
			<td>R&#38;D</td>
			<td>3500</td>
			<td>250 ng/mL</td>
		</tr>
		<tr>
			<td>SB202190</td>
			<td>Sigma</td>
			<td>S7067</td>
			<td>500 nM</td>
		</tr>
		<tr>
			<td>Y-27632</td>
			<td>Tocris</td>
			<td>1254</td>
			<td>5 &#181;M</td>
		</tr>
	</tbody>
</table>

isolation and functional assessment of human breast cancer stem cells from cell and tissue samples

Brustkrebsstammzellen (BCSCs) sind Krebszellen mit vererbten oder erworbenen stammzellähnlichen Eigenschaften. Trotz ihrer geringen Häufigkeit tragen sie wesentlich zur Entstehung, zum Rückfall, zur Metastasierung und zur Therapieresistenz von Brustkrebs bei. Es ist unerlässlich, die Biologie von Brustkrebsstammzellen zu verstehen, um neue therapeutische Ziele zur Behandlung von Brustkrebs zu identifizieren. Brustkrebsstammzellen werden isoliert und charakterisiert, basierend auf der Expression einzigartiger Zelloberflächenmarker wie CD44, CD24 und der enzymatischen Aktivität der Aldehyddehydrogenase (ALDH). Diese ALDHHighCD44+CD24- Zellen bilden die BCSC-Population und können durch fluoreszenzaktivierte Zellsortierung (FACS) für nachgeschaltete funktionelle Studien isoliert werden. Je nach wissenschaftlicher Fragestellung können unterschiedliche in vitro und in vivo Methoden verwendet werden, um die funktionellen Eigenschaften von BCSCs zu beurteilen. Hier stellen wir ein detailliertes experimentelles Protokoll zur Isolierung von humanen BCSCs sowohl aus heterogenen Populationen von Brustkrebszellen als auch aus primärem Tumorgewebe von Brustkrebspatientinnen zur Verfügung. Darüber hinaus heben wir nachgeschaltete In-vitro - und In-vivo-Funktionstests hervor, einschließlich koloniebildender Assays, Mammosphären-Assays, 3D-Kulturmodelle und Tumor-Xenograft-Assays, die zur Beurteilung der BCSC-Funktion verwendet werden können.

Das beschriebene Protokoll ermöglicht die Isolierung humaner BCSCs aus einer heterogenen Population von Brustkrebszellen, entweder aus Zelllinien oder aus dissoziiertem Tumorgewebe. Für jede gegebene Zelllinie oder Gewebeprobe ist es entscheidend, eine einheitliche Einzelzellsuspension zu erzeugen, um BCSCs mit maximaler Reinheit zu isolieren, da die Kontamination von Nicht-BCSC-Populationen zu variablen zellulären Reaktionen führen könnte, insbesondere wenn das Studienziel darin besteht, die Wirksamkeit von Therape...

Watch this Scientific Journal Video about Isolation and Functional Assessment of Human Breast Cancer Stem Cells from Cell and Tissue Samples at JoVE.com

Isolation and Functional Assessment of Human Breast Cancer Stem Cells from Cell and Tissue Samples

Dieses experimentelle Protokoll beschreibt die Isolierung von BCSCs aus Brustkrebszell- und Gewebeproben sowie die in vitro und in vivo Assays, die zur Beurteilung des BCSC-Phänotyps und der BCSC-Funktion verwendet werden können.

Isolierung und funktionelle Beurteilung menschlicher Brustkrebsstammzellen aus Zell- und Gewebeproben

Breast cancer stem cells (BCSCs) are cancer cells with inherited or acquired stem cell-like characteristics. Despite their low frequency, they are major ...

isolation-functional-assessment-human-breast-cancer-stem-cells-from

Research

JoVE Journal

Cancer Research

4.2K Aufrufe.  London Regional Cancer Program. Dieses experimentelle Protokoll beschreibt die Isolierung von BCSCs aus Brustkrebszell- und Gewebeproben sowie die in vitro und in vivo Assays, die zur Beurteilung des BCSC-Phänotyps und der BCSC-Funktion verwendet werden können.

Serie: Isolation and Functional Assessment of Human Breast Cancer Stem Cells from Cell and Tissue Samples

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.

Gründung der Krebszellkulturen von Human Konventionelle Osteosarkom Stem

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

Forschung

Krebsforschung

Utilizing Functional Genomics Screening to Identify Potentially Novel Drug Targets in Cancer Cell Spheroid Cultures

The identification of functional driver events in cancer is central to furthering our understanding of cancer biology and indispensable for the discovery of the next generation of novel drug targets. It is becoming apparent that more complex models of cancer are required to fully appreciate the contributing factors that drive tumorigenesis in vivo and increase the efficacy of novel therapies that make the transition from pre-clinical models to clinical trials.
Here we present a methodology for generating uniform and reproducible tumor spheroids that can be subjected to siRNA functional screening. These spheroids display many characteristics that are found in solid tumors that are not present in traditional two-dimension culture. We show that several commonly used breast cancer cell lines are amenable to this protocol. Furthermore, we provide proof-of-principle data utilizing the breast cancer cell line BT474, confirming their dependency on amplification of the epidermal growth factor receptor HER2 and mutation of phosphatidylinositol-4,5-biphosphate 3-kinase (PIK3CA) when grown as tumor spheroids. Finally, we are able to further investigate and confirm the spatial impact of these dependencies using immunohistochemistry.

Identifying novel drug targets that transition from pre-clinical testing to human trials is a scientific priority. To that end, here we describe a functional genomics approach for examining the impact of gene depletion on cancer cell line spheroids, which more appropriately model human cancers in vivo.

Functional Genomics Screening Verwendung zur Identifizierung möglicher neuer Wirkstoff-Targets in Cancer Cell Sphäroid-Kulturen

The identification of functional driver events in cancer is central to furthering our understanding of cancer biology and indispensable for the discovery ...

Synthesis and Characterization of an Aspirin-fumarate Prodrug that Inhibits NF&#954;B Activity and Breast Cancer Stem Cells

Inflammation is a cancer hallmark that underlies cancer incidence and promotion, and eventually progression to metastasis. Therefore, adding an anti-inflammatory drug to standard cancer regiments may improve patient outcome. One such drug, aspirin (acetylsalicylic acid, ASA), has been explored for cancer chemoprevention and anti-tumor activity. Besides inhibiting the cyclooxygenase 2-prostaglandin axis, ASA&#39;s anti-cancer activities have also been attributed to nuclear factor &#312;B (NF&#312;B) inhibition. Because prolonged ASA use may cause gastrointestinal toxicity, a prodrug strategy has been implemented successfully. In this prodrug design the carboxylic acid of ASA is masked and additional pharmacophores are incorporated.
This protocol describes how we synthesized an aspirin-fumarate prodrug, GTCpFE, and characterized its inhibition of the NF&#312;B pathway in breast cancer cells and attenuation of the cancer stem-like properties, an important NF&#312;B-dependent phenotype. GTCpFE effectively inhibits the NF&#312;B pathway in breast cancer cell lines whereas ASA lacks any inhibitory activity, indicating that adding fumarate to ASA structure significantly contributes to its activity. In addition, GTCpFE shows significant anti-cancer stem cell activity by blocking mammosphere formation and attenuating the cancer stem cell associated CD44+CD24- immunophenotype. These results establish a viable strategy to develop improved anti-inflammatory drugs for chemoprevention and cancer therapy.

Synthesis and Characterization of an Aspirin-fumarate Prodrug that Inhibits NF&amp;#954;B Activity and Breast Cancer Stem Cells

This procedure will demonstrate how we synthesized and characterized the anti-NF&#954;B and anti-cancer stem cell activity of an aspirin-fumarate prodrug.

Synthese und Charakterisierung eines Aspirin-Fumarat Prodrug, die NFkB-Aktivität hemmt und Brustkrebs-Stammzellen

Inflammation is a cancer hallmark that underlies cancer incidence and promotion, and eventually progression to metastasis. Therefore, adding an ...

Invasive Behavior of Human Breast Cancer Cells in Embryonic Zebrafish

In many cases, cancer patients do not die of a primary tumor, but rather because of metastasis. Although numerous rodent models are available for studying cancer metastasis in vivo, other efficient, reliable, low-cost models are needed to quickly access the potential effects of (epi)genetic changes or pharmacological compounds. As such, we illustrate and explain the feasibility of xenograft models using human breast cancer cells injected into zebrafish embryos to support this goal. Under the microscope, fluorescent proteins or chemically labeled human breast cancer cells are transplanted into transgenic zebrafish embryos, Tg (fli:EGFP), at the perivitelline space or duct of Cuvier (Doc) 48 h after fertilization. Shortly afterwards, the temporal-spatial process of cancer cell invasion, dissemination, and metastasis in the living fish body is visualized under a fluorescent microscope. The models using different injection sites, i.e., perivitelline space or Doc are complementary to one another, reflecting the early stage (intravasation step) and late stage (extravasation step) of the multistep metastatic cascade of events. Moreover, peritumoral and intratumoral angiogenesis can be observed with the injection into the perivitelline space. The entire experimental period is no more than 8 days. These two models combine cell labeling, micro-transplantation, and fluorescence imaging techniques, enabling the rapid evaluation of cancer metastasis in response to genetic and pharmacological manipulations.

Here, we describe xenograft zebrafish models using two different injection sites, i.e., perivitelline space and duct of Cuvier, to investigate the invasive behavior and to assess the intravasation and extravasation potential of human breast cancer cells, respectively.

Invasive Verhalten von menschlichen Brustkrebszellen in embryonalem Zebrabärbling

In many cases, cancer patients do not die of a primary tumor, but rather because of metastasis. Although numerous rodent models are available for studying ...

Flow Cytometric Detection of Newly-formed Breast Cancer Stem Cell-like Cells After Apoptosis Reversal

Cancer recurrence has long been studied by oncologists while the underlying mechanisms remain unclear. Recently, we and others found that a phenomenon named apoptosis reversal leads to increased tumorigenicity in various cell models under different stimuli. Previous studies have been focused on tracking this process in vitro and in vivo; however, the isolation of real reversed cells has yet to be achieved, which limits our understanding on the consequences of apoptosis reversal. Here, we take advantage of a Caspase-3/7 Green Detection dye to label cells with activated caspases after apoptotic induction. Cells with positive signals are further sorted out by fluorescence-activated cell sorting (FACS) for recovery. Morphological examination under confocal microscopy helps confirm the apoptotic status before FACS. An increase in tumorigenicity can often be attributed to the elevation in the percentage of cancer stem cell (CSC)-like cells. Also, given the heterogeneity of breast cancer, identifying the origin of these CSC-like cells would be critical to cancer treatment. Thus, we prepare breast non-stem cancer cells before triggering apoptosis, isolating caspase-activated cells and performing the apoptosis reversal procedure. Flow cytometry analysis reveals that breast CSC-like cells re-appear in the reversed group, indicating breast CSC-like cells are transited from breast non-stem cancer cells during apoptosis reversal. In summary, this protocol includes the isolation of apoptotic breast cancer cells and detection of changes in CSC percentage in reversed cells by flow cytometry.

Here, we present a protocol to isolate apoptotic breast cancer cells by fluorescence-activated cell sorting and further detect the transition of breast non-stem cancer cells to breast cancer stem cell-like cells after apoptosis reversal by flow cytometry.

Flow durchflusszytometrischen Erkennung von neu gebildeten Stammzellen-wie Brustkrebszellen nach Apoptose Umkehr

Cancer recurrence has long been studied by oncologists while the underlying mechanisms remain unclear. Recently, we and others found that a phenomenon ...

Mesenchymal Stem Cell Isolation from Pulp Tissue and Co-Culture with Cancer Cells to Study Their Interactions

Cancer as a multistep process and complicated disease is not only regulated by individual cell proliferation and growth but also controlled by tumor environment and cell-cell interactions. Identification of cancer and stem cell interactions, including changes in extracellular environment, physical interactions, and secreted factors, might enable the discovery of new therapy options. We combine known co-culture techniques to create a model system for mesenchymal stem cells (MSCs) and cancer cell interactions. In the current study, dental pulp stem cells (DPSCs) and PC-3 prostate cancer cell interactions were examined by direct and indirect co-culture techniques. Condition medium (CM) obtained from DPSCs and 0.4 &#181;m pore sized trans-well membranes were used to study paracrine activity. Co-culture of different cell types together was performed to study direct cell-cell interaction. The results revealed that CM increased cell proliferation and decreased apoptosis in prostate cancer cell cultures. Both CM and trans-well system increased cell migration capacity of PC-3 cells. Cells stained with different membrane dyes were seeded into the same culture vessels, and DPSCs participated in a self-organized structure with PC-3 cells under this direct co-culture condition. Overall, the results indicated that co-culture techniques could be useful for cancer and MSC interactions as a model system.

We provide protocols for evaluation of mesenchymal stem cells isolated from dental pulp and prostate cancer cell interactions based on direct and indirect co-culture methods. Condition medium and trans-well membranes are suitable to analyze indirect paracrine activity. Seeding differentially stained cells together is an appropriate model for direct cell-cell interaction.

Mesenchymale Stammzellen isoliert von Pulpagewebe und Kokultur mit Krebszellen ihre Interaktionen zu untersuchen

Cancer as a multistep process and complicated disease is not only regulated by individual cell proliferation and growth but also controlled by tumor ...

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.

Beschaffung von Krebsstammzellkugeln aus gynäkologischen und Brustkrebstumoren

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

Functional Assessment of BRCA1 variants using CRISPR-Mediated Base Editors

Recent studies have investigated the risks associated with BRCA1 gene mutations using various functional assessment methods such as fluorescent reporter assays, embryonic stem cell viability assays, and therapeutic drug-based sensitivity assays. Although they have clarified a lot of BRCA1 variants, these assays involving the use of exogenously expressed BRCA1 variants are associated with overexpression issues and cannot be applied to post-transcriptional regulation. To resolve these limitations, we previously reported a method for functional analysis of BRCA1 variants via CRISPR-mediated cytosine base editor that induce targeted nucleotide substitution in living cells. Using this method, we identified variants whose functions remain ambiguous, including c.-97C&#62;T, c.154C&#62;T, c.3847C&#62;T, c.5056C&#62;T, and c.4986+5G&#62;A, and confirmed that CRISPR-mediated base editors are useful tools for reclassifying the variants of uncertain significance in BRCA1. Here, we describe a protocol for functional analysis of BRCA1 variants using CRISPR-based cytosine base editor. This protocol provides guidelines for the selection of target sites, functional analysis and evaluation of BRCA1 variants.

Functional Assessment of BRCA1 variants using CRISPR-Mediated Base Editors

People with BRCA1 mutations have a higher risk of developing cancer, which warrants accurate evaluation of the function of BRCA1 variants. Herein, we described a protocol for functional assessment of BRCA1 variants using CRISPR-mediated cytosine base editors that enable targeted C:G to T:A conversion in living cells.

Funktionsbewertung von BRCA1-Varianten mit CRISPR-mediated Base Editors

Recent studies have investigated the risks associated with BRCA1 gene mutations using various functional assessment methods such as fluorescent reporter ...

Modeling Breast Cancer in Human Breast Tissue using a Microphysiological System

Breast cancer (BC) remains a leading cause of death for women. Despite more than $700 million invested in BC research annually, 97% of candidate BC drugs fail clinical trials. Therefore, new models are needed to improve our understanding of the disease. The NIH Microphysiological Systems (MPS) program was developed to improve the clinical translation of basic science discoveries and promising new therapeutic strategies. Here we present a method for generating MPS for breast cancers (BC-MPS). This model adapts a previously described approach of culturing primary human white adipose tissue (WAT) by sandwiching WAT between adipose-derived stem cell sheets (ASC)s. Novel aspects of our BC-MPS include seeding BC cells into non-diseased human breast tissue (HBT) containing native extracellular matrix, mature adipocytes, resident fibroblasts, and immune cells; and sandwiching the BC-HBT admixture between HBT-derived ASC sheets. The resulting BC-MPS is stable in culture ex vivo for at least 14 days. This model system contains multiple elements of the microenvironment that influence BC including adipocytes, stromal cells, immune cells, and the extracellular matrix. Thus BC-MPS can be used to study the interactions between BC and its microenvironment. 
We demonstrate the advantages of our BC-MPS by studying two BC behaviors known to influence cancer progression and metastasis: 1) BC motility and 2) BC-HBT metabolic crosstalk. While BC motility has previously been demonstrated using intravital imaging, BC-MPS allows for high-resolution time-lapse imaging using fluorescence microscopy over several days. Furthermore, while metabolic crosstalk was previously demonstrated using BC cells and murine pre-adipocytes differentiated into immature adipocytes, our BC-MPS model is the first system to demonstrate this crosstalk between primary human mammary adipocytes and BC cells in vitro.

This protocol describes the construction of an in vitro microphysiological system for studying breast cancer using primary human breast tissue with off the shelf materials.

Modellierung von Brustkrebs im menschlichen Brustgewebe mit einem mikrophysiologischen System

Breast cancer (BC) remains a leading cause of death for women. Despite more than $700 million invested in BC research annually, 97% of candidate BC drugs ...

A Rapid Screening Workflow to Identify Potential Combination Therapy for GBM using Patient-Derived Glioma Stem Cells

The glioma stem cells (GSCs) are a small fraction of cancer cells which play essential roles in tumor initiation, angiogenesis, and drug resistance in glioblastoma (GBM), the most prevalent and devastating primary brain tumor. The presence of GSCs makes the GBM very refractory to most of individual targeted agents, so high-throughput screening methods are required to identify potential effective combination therapeutics. The protocol describes a simple workflow to enable rapid screening for potential combination therapy with synergistic interaction. The general steps of this workflow consist of establishing luciferase-tagged GSCs, preparing matrigel coated plates, combination drug screening, analyzing, and validating the results.

Ein schneller Screening-Workflow zur Identifizierung einer potenziellen Kombinationstherapie für GBM unter Verwendung von vom Patienten abgeleiteten Gliomstammzellen

The glioma stem cells (GSCs) are a small fraction of cancer cells which play essential roles in tumor initiation, angiogenesis, and drug resistance in ...