Supportato in parte da una sovvenzione del National Cancer Institute 1R03CA172923.

Etica Dichiarazione: L&#39;uso di topi nella ricerca è accettabile solo nei casi in cui si potrebbe avanzare la comprensione umana della biologia fondamentale o verso l&#39;eventuale trattamento della malattia. 1. Ordine <ol><li> Acquisto femminile C57BL / 6 topi (all&#39;età di 6 - 8 settimane), 5 topi per gruppo. Consentire diversi giorni per i topi per regolare. </li></ol> 2. Preparazione di cellule B16-BL6 <ol><li> Rimuovere piastre di coltura di cellule da incubatore a 37 gradi e posto in una cappa sterile. Le piastre devono essere circa il 70% confluenti con cellule di melanoma murino B16-BL6. Una maggiore confluenza può alterare le cellule potenziale metastatico. </li><li> Aggiungere 1 ml di 0,05% tripsina-EDTA per piastra, lasciate riposare per 1 minuto, e poi aspirare la soluzione di tripsina-media. </li><li> Aggiungere 1 ml di tripsina per piastra e tornare piastre incubatrice per 10 min. </li><li> Dopo aver spostato le piastre dal termostato alla cappa sterile, aggiungere 4 ml di privo di siero Rosewell Park Memorial Institute Medium (RPMI) per ogni piatto. </li><li> Raccogliere le cellule con una sterile, pipetta motorizzato. Estrarre cellule contro il fondo della piastra, con la punta pressata a una leggera angolazione, per rompere le cellule. Ripetere più volte al fine di garantire un&#39;adeguata separazione dei grumi di cellule, che altrimenti potrebbero intasare l&#39;ago espulsione. Ricordare e trasferire in una provetta conica da 50 ml. </li><li> Utilizzare un emocitometro per determinare la densità cellulare. Mantenere il numero totale di cellule B16-BL6 costante, determinare il volume di RPMI senza siero necessario per raggiungere concentrazioni finali di 0, 0,065, 0,015, 0,25 e 0,5 milioni di cellule / ml. </li><li> Altrettanto un&#39;aliquota media del tubo da 50 ml a 15 ml provette coniche. Centrifugare le provette coniche a 2.250 xg per 5 min. Decantare il supporto. Aggiungere un volume adeguato di RPMI senza siero e confermare la densità cellulare desiderato tramite emocitometro. Regolare densities- con l&#39;aggiunta di ulteriore RPMI o filatura e risospensione in un volume- più piccolo di conseguenza. </li><li> Aliquota 500 microlitridi ciascuna sospensione cellulare in etichettato 1,8 ml provette su ghiaccio. </li></ol> 3. Tail Vein Injection <ol><li> Prendere un topo, che si tiene per la coda, e guidarla posteriore prima nel dispositivo di immobilizzazione del mouse. Con il torso nella camera principale del dispositivo di immobilizzazione, con la coda fuori, tirare il mouse verso la fine del dispositivo di immobilizzazione. Inserire il dispositivo di immobilizzazione-stantuffo, continuando a spingere fino a quando il mouse è sicuro. </li><li> Ruotare il mouse 90 gradi in modo che una delle vene coda laterale rivolta in alto. Usando un tampone di alcool, vigorosamente pulire il lato di coda del topo, in particolare quando la vena della coda è più visibile. Nota: Una buona illuminazione è essenziale per la coda efficace visualizzazione vena sul B57BL 6J /. lampade di calore o pastiglie chirurgia riscaldata, mentre non necessario, aiuterà anche aumentando il volume della vena della coda. </li><li> In una cappa sterile cultura, raccogliere 300 ml di terreni di coltura delle cellule dal / tubo di 2 milioni di cellule ml. Invertire l&#39;ago, sfogliando le side e spingendo lo stantuffo, per espellere le bolle dalla siringa. Estrarre coltura RPMI-tradursi in un volume finale di 250 microlitri. </li><li> Estendere il mouse-coda con la mano non dominante. Tenere la coda con l&#39;estremità prossimale della coda elevata con l&#39;indice della mano non dominante, e la porzione distale della coda premuto con il pollice. Nota: In questo modo, la vena della coda viene tenuto in posizione laterale, parallelo alla superficie restrainer, con una voce congruente possibile nella parte più distale della coda. </li><li> Inserire l&#39;ago nella vena della coda, verso l&#39;estremità distale, ad un angolo verso il basso minuti per cominciare, e quindi regolare l&#39;ago per abbinare l&#39;angolo della vena caudale dopo ulteriore inserimento (abbassamento fine stantuffo della siringa rispetto all&#39;ago) . </li><li> Inserire l&#39;ago di circa 1 cm nel vena della coda. Dopo l&#39;inserimento, iniziano a spingere lo stantuffo, tenendo l&#39;ago costante. Nota: Se l&#39;ago è in vena della coda e l&#39;estremità dell&#39;ago è not ostruito i media dovrebbero fluire senza ostacoli nella vena. iniezione efficace è caratterizzata da depurazione del sangue dalla vena. Se c&#39;è resistenza, o una bolla inizia a formarsi il sito in iniezione, rimuovere l&#39;ago e riprovare in una posizione più prossimale lungo la vena della coda. </li><li> Rimuovere l&#39;ago dalla vena e disfarsene. Tenere garza contro il sito di entrata per fermare le emorragie. </li><li> Rimuovere lo stantuffo dalla restrainer e posizionare il mouse nella gabbia destinatario. </li><li> Ripetere l&#39;operazione per tutte le altre concentrazioni. Nota:. Lung stabilimento foci richiede circa 2 - 3 settimane, con variabilità a seconda della linea cellulare e la dimensione desiderata dei fuochi 9 Nel frattempo, i topi devono essere monitorati per sintomi che potrebbero giustificare l&#39;eutanasia presto, come ansimante eccessivo. </li></ol> 4. Contare il polmone Foci <ol><li> Euthanize il mouse posizionando in una camera di CO 2 ed esponendo al 100% CO 2 </sub&gt; introdotto al 10-30% del volume della camera per minuto per 5 min. Seguire con una dislocazione cervicale. </li><li> Splay il mouse sul polistirolo. Utilizzando forbici chirurgiche, creare una incisione chirurgica lungo lo sterno. </li><li> Fare due incisioni aggiuntivi, sia dalla parte superiore dell&#39;incisione sterno e ramificazione verso le spalle del mouse, esponendo la gabbia toracica. </li><li> Fare due tagli, ciascuno lungo i lati laterali dello sterno, per rimuovere la gabbia toracica dal tronco, esponendo i polmoni e il cuore. </li><li> Tenendo cuore con le pinzette chirurgiche, tagliare l&#39;esofago e la trachea, liberando il cuore ei polmoni dal mouse. Mettere sotto un microscopio da dissezione, a 10X di ingrandimento, per una migliore visualizzazione. </li><li> Sezionare cuore dai polmoni e rimuovere il timo, lasciando solo i due polmoni. </li><li> Con i polmoni sotto un ambito dissezione, cominciare a contare i fuochi polmone. Ogni foci dovrebbe apparire come circolare, obtrusion marrone sulla superficie dei polmoni. <ol><li> Percoerenza tra topi, contare il numero di focolai sulla superficie di un lobo, e poi invertire tale lobo. Facendo ciascuno dei quattro lobi permette singolarmente per il conteggio più facile. </li></ol></li><li> Salvare e fissare i polmoni se l&#39;esecuzione di IHC, in caso contrario, eliminare i resti. </li></ol>

<ol>
	<li>Chaffer, C. L., Weinberg, R. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+perspective+on+cancer+cell+metastasis.">A perspective on cancer cell metastasis.</a> Science. 331, 1559-1564 (2011).</li><li>Kalluri, R., Weinberg, R. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+basics+of+epithelial-mesenchymal+transition.">The basics of epithelial-mesenchymal transition.</a> J Clin Invest. 119 (6), 1420-1428 (2009).</li><li>Stetler-Stevenson, W. G., Aznavoorian, S., Liotta, L. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Tumor+cell+interactions+with+the+extracellular+matrix+during+invasion+and+metastasis.">Tumor cell interactions with the extracellular matrix during invasion and metastasis.</a> Annu Rev Cell Biol. 9, 541-573 (1993).</li><li>Allard, W. J., Matera, J., Miller, M. C., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Tumor+cells+circulate+in+the+peripheral+blood+of+all+major+carcinomas+but+not+in+healthy+subjects+or+patients+with+nonmalignant+disease.">Tumor cells circulate in the peripheral blood of all major carcinomas but not in healthy subjects or patients with nonmalignant disease.</a> Clin Cancer Res. 10, 6897-6904 (2004).</li><li>Dunn, G. P., Bruce, A. T., Ikeda, H., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Cancer+immunoediting:+from+iimmunosurveillance+to+tumor+escape.">Cancer immunoediting: from iimmunosurveillance to tumor escape.</a> Nat Immunol. 3, 991-998 (2002).</li><li>Hugo, H., Ackland, M. L., Blick, T., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Epithelial-mesenchymal+and+mesenchymal-epithelial+transition+in+carcinoma+progression.">Epithelial-mesenchymal and mesenchymal-epithelial transition in carcinoma progression.</a> J Cell Physiol. 213, 374-383 (2007).</li><li>Kang, Y., Massague, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Epithelial-mesenchymal+transitions:+Twist+in+development+and+metastasis.">Epithelial-mesenchymal transitions: Twist in development and metastasis.</a> Cell. 118, 277-279 (2004).</li><li>Hodi, S. F., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Improved+survival+with+Ipilimumab+in+patients+with+metastatic+melanoma.">Improved survival with Ipilimumab in patients with metastatic melanoma.</a> NEJM. 363 (13), 711-723 (2002).</li><li>Ekwueme, D. U., Guy, G. P., Li, C., Rim, S. H., Parelkar, P., Chen, S. C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+health+burden+and+economic+costs+of+cutaneous+melanoma+motality+by+race/ethnicity-United+States.">The health burden and economic costs of cutaneous melanoma motality by race/ethnicity-United States.</a> J. Am. Acad. Dermatol. 65, 133-143 (2011).</li><li>Alizadeh, A. 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Oncol. 1 (3), 263-264 (2007).</li><li>Ishiguro, T., Nakajima, M., Naito, M., Muto, T., Tsuruo, T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Identification+of+genes+differentially+expressed+in+B16+murine+melanoma+sublines+with+different+metastatic+potentials.">Identification of genes differentially expressed in B16 murine melanoma sublines with different metastatic potentials.</a> Cancer Res. 56 (4), 875-879 (1996).</li><li>Clark, E. A., Todd, R. G., Lander, E. S., Hynes, R. O. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Genomic+analysis+of+metastasis+reveals+an+essential+role+for+RhoC.">Genomic analysis of metastasis reveals an essential role for RhoC.</a> Nature. 406, 532-535 (2000).</li><li>Terranova, V. P., Hic, S., Diflorio, R. M., Lyall, R. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Tumor+cell+metastasis.">Tumor cell metastasis.</a> Crit. Rev. Oncol. Hematol. 5 (2), 87-114 (1986).</li><li>Elkin, M., Vlodavsky, I. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Tail+vein+assay+of+cancer+metastasis.">Tail vein assay of cancer metastasis.</a> Curr Protoc in Cell Biol. , (2001).</li><li>Hagedorn, H. G., Bachmeier, B. E., Nerlich, A. G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Synthesis+and+degradation+of+basement+membranes+and+extracellular+matrix+and+their+regulation+by+TGF-beta+in+invasive+carcinomas+(Review).">Synthesis and degradation of basement membranes and extracellular matrix and their regulation by TGF-beta in invasive carcinomas (Review).</a> Int. J. Oncol. 18 (4), 669-681 (2001).</li><li>Hart, I. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+selection+and+characterization+of+an+invasive+variant+of+the+B16+melanoma.">The selection and characterization of an invasive variant of the B16 melanoma.</a> Am J Pathol. 97 (3), 587-600 (1979).</li><li>Overwijk, W. 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Gli autori dichiarano di non avere interessi finanziari concorrenti.

Circolanti cellule tumorali da una iniezione coda vena rappresentare le metastasi che eludono i siti di crescita primaria e migrare attraverso percorsi come il sangue o il sistema linfatico, di tanto in tanto si stabilisce nei letti capillari di luoghi distanti. 14 Il protocollo sopra descritto serve da modello per la secondaria metastasi. Con un numero ottimale di cellule B16-BL6 iniettato, sperimentatori in grado di determinare l&#39;effetto relativo di un farmaco somministrato o di una popolazione di cellule immunitarie, post-neutralizzazione, sulle metastasi delle cellule tumorali. Questo protocollo ha limitazioni. Le cellule tumorali circolanti sono state selezionate per la loro capacità di metastatizzare e sono quindi non immunogenica, con livelli inferiori di maggiore di istocompatibilità di classe complessa 1 molecole. 12 Inoltre, l&#39;introduzione improvvisa e cluster di gran numero di metastasi è diverso scenario tipico in pazienti dove un piccolo numero di cellule tumorali metastatichedissipare per un periodo prolungato di tempo dalla localizzazione del tumore primario. Inoltre, le cellule tumorali per via endovenosa introdotte sono da coltura tissutale e non di origine tumore primario. Pertanto, queste cellule sono a differenza delle metastasi secondarie che derivano da alterazioni nella adesione cellulare, la migrazione, il riconoscimento immunitario e stabilimento organo ricevente. 15,16 Un protocollo alternativo sarebbe l&#39;iniezione sottocutanea di B16 / BL6 per la generazione di tumori primari e l&#39;analisi delle risultanti metastasi polmonari &quot;spontanee&quot;. Queste metastasi &quot;spontanee&quot; sono stati trovati per contenere più l&#39;eterogeneità delle loro controparti &quot;sperimentali&quot;, più strettamente corrispondono a quelli dei pazienti umani. Il protocollo è limitante nella sua capacità di determinare l&#39;influenza di un composto sperimentale di metastasi. Con una laterale iniezione vena della coda, il numero di cellule di melanoma iniettato nel sangue può essere approssimata tramite hemocytometer. Con metastasi &quot;spontanee&quot;, tuttavia, vi è una maggiore eterogeneità tra tumori, aggiungendo un&#39;ulteriore variabile per il numero di foci risultante polmonare. 16 In conclusione, la B16-BL6 modello di melanoma murino vena della coda rappresenta un modello semplice per determinare l&#39;influenza di un trattamento o immunoterapia in metastasi. In via endovenosa iniezione di cellule tumorali circolanti, i ricercatori possono replicare, in una certa misura, i pazienti post-metastasi. Considerando gli effetti distruttivi delle cellule tumorali metastatiche nei pazienti affetti da cancro, questo modello è un potente strumento per la comprensione del processo multistep di metastasi.

Metastasi è una delle principali cause di morte tra i pazienti con neoplasie. Il processo di diffusione metastatica delle cellule tumorali è poco conosciuta, ma sembra coinvolgere diversi passaggi, tra cui invasione dei tessuti adiacenti, intravasation nei vasi linfatici e vasi, la sopravvivenza e la traslocazione all&#39;interno del sistema circolatorio, stravaso dal sistema vascolare presso il sito di metastasi, l&#39;adattamento al nuovo microambiente del nuovo sito, e la colonizzazione al nuovo sito proliferazione e formazione di tumori secondari. 1 Ciascuno di questi eventi biologici coinvolgono la trasformazione, la diffusione e la sopravvivenza delle cellule tumorali metastatiche. Per esempio, la trasformazione del fenotipo epiteliale della cellula tumorale in un fenotipo mesenchimale, accoppiato con l&#39;interazione positiva con la matrice extracellulare, consentire loro di invadere i tessuti adiacenti e metastasi in altre parti del corpo. 2,3 Inoltre, questi metastatico celluledeve sopravvivere all&#39;interno del flusso sanguigno circolante e evadere la sorveglianza immunitaria dall&#39;host. 4,5 Infine, quando impiantato in un sito lontano all&#39;interno del corpo, le cellule tumorali devono adattarsi al loro microambiente per proliferare e formare tumori secondari. 6,7 Pertanto , anche se le metastasi è un fenomeno comune tra i pazienti affetti da cancro, le cellule tumorali metastatiche hanno molteplici aree di vulnerabilità che sono suscettibili di intervento terapeutico. Data la natura immunogenica del melanoma, e il recente interesse per le immunoterapie, modelli per il melanoma sono sempre più utile. 8 Nei soli Stati Uniti, il melanoma è la causa di una stima di 9.000 morti l&#39;anno. 9 sedi comuni di metastasi del melanoma sono ossa, cervello , fegato e polmoni. La maggior parte delle metastasi a siti distanti avviene attraverso il flusso sanguigno. Circolanti cellule tumorali nel sangue deve eludere spazio immunitario, raggiungere un letto capillare di un organo distale einvadono attraverso le cellule endoteliali dei vasi sanguigni per stabilire correttamente se stessi. 4-7,10, 11 Per simulare i fenomeni comuni e virulenti di metastasi, è stato creato la linea cellulare B16-BL6 murino. Un defunto della parentali C57BL / 6 linea di cellule di melanoma B16-F0, B16-BL6 è il prodotto finale di 10 selezioni successive per metastasi polmonari da iniezione endovenosa (con conseguente B16-F10), seguita da 6 selezioni successive per la penetrazione della membrana della vescica. 12 come tale, è una linea cellulare di melanoma affidabile per la creazione di foci metastatici nel topo, in particolare quando iniettato per via endovenosa. 13 Dopo l&#39;iniezione di una quantità sufficiente di B16-BL6 cellule nella vena della coda di un B57BL / 6 del mouse, seguito da due o più settimane per permettere impianto e la crescita delle cellule B16 / BL6, foci metastatici formerà nei polmoni. Al momento l&#39;eutanasia e l&#39;ispezione al microscopio dissezione, il numero difoci presente individuo può essere quantificato. Questo, a sua volta, può essere utilizzato per stabilire un effetto dose-metastasi, come il numero di cellule B16-BL6 iniettati è correlato al numero di foci formata sulla superficie dei polmoni. Questo modello è conosciuto come &quot;metastasi sperimentale&quot;, in cui le cellule conosciute metastatico vengono introdotti direttamente nel flusso sanguigno, favorendo una diffusione rapida e prevedibile e stabilimento nel polmoni, fegato, o di altro organo di indagine. Questo è in contrasto con &quot;metastasi spontanee&quot;, in cui le cellule tumorali vengono impiantati, spesso per via sottocutanea, e metastasi provengono da organicamente capannone cellule tumorali. 14,15 E &#39;importante per iniettare una quantità appropriata di cellule B16 / BL6 nelle vene coda dei topi. Troppi, ei polmoni saranno coperti con metastasi e la vicina focolai saranno indistinguibili gli uni dagli altri. Troppo pochi, e l&#39;influenza di un agente terapeutico sarà indistinguibile causa intrinseca varizioni tra le iniezioni. Per ottenere un numero ottimale di foci sui polmoni dei C57BL 6 topi /, è necessario correlare il numero di cellule iniettate con la quantità di foci metastatici stabilito sulla superficie dei polmoni tenendo conto la distinguibilità dei singoli foci. Questo protocollo dimostrerà un modello murino di melanoma metastatico in topi C57BL / 6.

<table border="0" cellpadding="0" cellspacing="0" width="1227">
	<tbody>
		<tr height="21">
			<td height="21" style="height:21px;width:377px;">Trypsin</td>
			<td style="width:275px;">Corning</td>
			<td style="width:288px;">MT25052CV</td>
			<td style="width:287px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">RPMI 1640 Medium</td>
			<td>Corning</td>
			<td>MT15040CM</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Phase Contraast Hemacytometer</td>
			<td>Hausser</td>
			<td>02-671-54</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Micro-Fine IV Insulin Syringes</td>
			<td>BD</td>
			<td>14-829-1D</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Sterile Alcohol Prep Pads</td>
			<td>Fisherbrand</td>
			<td>22-363-750</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Mouse Restrainer</td>
			<td>Braintree Scientific</td>
			<td>NC9999969</td>
			<td>Restrainer choice depends on age/size of mice</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Heating Pad</td>
			<td>Harry Schein</td>
			<td>NC0012697</td>
			<td>Optional</td>
		</tr>
	</tbody>
</table>

injection of syngeneic murine melanoma cells to determine their metastatic potential in the lungs

Approximately 90% of human cancer deaths are linked to metastasis. Despite the prevalence and relative harm of metastasis, therapeutics for treatment or prevention are lacking. We report a method for the establishment of pulmonary metastases in mice, useful for the study of this phenomenon. Tail vein injection of B57BL/6J mice with B16-BL6 is among the most used models for melanoma metastases. Some of the circulating tumor cells establish themselves in the lungs of the mouse, creating "experimental" metastatic foci. With this model it is possible to measure the relative effects of therapeutic agents on the development of cancer metastasis. The difference in enumerated lung foci between treated and untreated mice indicates the efficacy of metastases neutralization. However, prior to the investigation of a therapeutic agent, it is necessary to determine an optimal number of injected B16-BL6 cells for the quantitative analysis of metastatic foci. Injection of too many cells may result in an overabundance of metastatic foci, impairing proper quantification and overwhelming the effects of anti-cancer therapies, while injection of too few cells will hinder the comparison between treated and controls.

Su ispezione visiva, la variazione foci superficie è evidente. Contando il numero di tumori sotto un microscopio da dissezione dovrebbe produrre una relazione lineare tra il numero di cellule tumorali iniettate e il numero di foci risultante e numerabile. Utilizzando un numero ottimale di cellule iniettabili, l&#39;obiettivo è quello in cui i polmoni non sono completamente coperti, in quanto sono a 500.000 cellule / ml in figura 1A, e non troppo scarsamente coperte, come sono a 62.500 cellule / ml e 125.000 cellule / ml. Questo è anche quantificabile dalla correlazione lineare (Figura 1B). <img alt="Figura 1" src="/files/ftp_upload/54039/54039fig1.jpg" /> Figura 1. Lung Foci risultante dalla vena della coda hanno iniettato cellule B16 / BL6. (A) foci polmone può essere visualizzata sulla superficie dei polmoni da C57BL / 6 topi come masse circolari marrone (foci rappresentante alle frecce). Come le tanelità della coltura cellulare iniettato (sopra ogni immagine) aumenta, così fa il corrispondente numero di focolai risultante polmone (sotto ogni immagine). I polmoni del mouse con la più alta densità di cellule iniettate ha la maggiore copertura visiva di foci del polmone. Barre di scala rappresentano 20 mm. (B) enumerazione dei fuochi polmone rispetto alla densità di coltura cellulare. Esiste una relazione approssimativamente lineare sopra 125.000 cellule / ml, come determinato da emocitometro. <a href="https://www.jove.com/files/ftp_upload/54039/54039fig1large.jpg" target="_blank">Si prega di cliccare qui per vedere una versione più grande di questa figura.</a>

Watch this Scientific Journal Video about Injection of Syngeneic Murine Melanoma Cells to Determine Their Metastatic Potential in the Lungs at JoVE.com

Injection of Syngeneic Murine Melanoma Cells to Determine Their Metastatic Potential in the Lungs

Metastasis plays a profound role in the virulence of cancer, accounting for an estimated 90% of deaths. We report a protocol for a metastatic melanoma model in mice that is useful for determining the efficacy of therapeutic agents against this clinical phenomenon.

Iniezione di cellule singenici del topo melanoma per determinare il loro potenziale metastatico nei polmoni

Approximately 90% of human cancer deaths are linked to metastasis.  Despite the prevalence and relative harm of metastasis, therapeutics for treatment or ...

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JoVE Journal

Medicine

17.5K Views.  Beth Israel Deaconess Medical Center & Harvard Medical School. Metastasis plays a profound role in the virulence of cancer, accounting for an estimated 90% of deaths. We report a protocol for a metastatic melanoma model in mice that is useful for determining the efficacy of therapeutic agents against this clinical phenomenon.

Video: Injection of Syngeneic Murine Melanoma Cells to Determine Their Metastatic Potential in the Lungs

An In Vitro System to Study Tumor Dormancy and the Switch to Metastatic Growth

Recurrence of breast cancer often follows a long latent period in which there are no signs of cancer, and metastases may not become clinically apparent until many years after removal of the primary tumor and adjuvant therapy. A likely explanation of this phenomenon is that tumor cells have seeded metastatic sites, are resistant to conventional therapies, and remain dormant for long periods of time 1-4.
The existence of dormant cancer cells at secondary sites has been described previously as quiescent solitary cells that neither proliferate nor undergo apoptosis 5-7. Moreover, these solitary cells has been shown to disseminate from the primary tumor at an early stage of disease progression 8-10 and reside growth-arrested in the patients' bone marrow, blood and lymph nodes 1,4,11. Therefore, understanding mechanisms that regulate dormancy or the switch to a proliferative state is critical for discovering novel targets and interventions to prevent disease recurrence. However, unraveling the mechanisms regulating the switch from tumor dormancy to metastatic growth has been hampered by the lack of available model systems.
in vivo and ex vivo model systems to study metastatic progression of tumor cells have been described previously 1,12-14. However these model systems have not provided in real time and in a high throughput manner mechanistic insights into what triggers the emergence of solitary dormant tumor cells to proliferate as metastatic disease. We have recently developed a 3D in vitro system to model the in vivo growth characteristics of cells that exhibit either dormant (D2.OR, MCF7, K7M2-AS.46) or proliferative (D2A1, MDA-MB-231, K7M2) metastatic behavior in vivo . We demonstrated that tumor cells that exhibit dormancy in vivo at a metastatic site remain quiescent when cultured in a 3-dimension (3D) basement membrane extract (BME), whereas cells highly metastatic in vivo readily proliferate in 3D culture after variable, but relatively short periods of quiescence. Importantly by utilizing the 3D in vitro model system we demonstrated for the first time that the ECM composition plays an important role in regulating whether dormant tumor cells will switch to a proliferative state and have confirmed this in in vivo studies15-17. Hence, the model system described in this report provides an in vitro method to model tumor dormancy and study the transition to proliferative growth induced by the microenvironment.

An In Vitro System to Study Tumor Dormancy and the Switch to Metastatic Growth

A modified 3-D in vitro system is presented in which growth characteristics of several tumor cell lines in reconstituted basement membrane correlate with the dormant or proliferative behavior of the tumor cells at a metastatic secondary site in vivo.

Un In Vitro Sistema per studio dormienza tumorale e l&#39;interruttore di crescita metastatica

Recurrence of breast cancer often follows a long latent period in which there are no signs of cancer, and metastases may not become clinically apparent ...

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Medicina

The Measurement and Treatment of Suppression in Amblyopia

Amblyopia, a developmental disorder of the visual cortex, is one of the leading causes of visual dysfunction in the working age population. Current estimates put the prevalence of amblyopia at approximately 1-3%1-3, the majority of cases being monocular2. Amblyopia is most frequently caused by ocular misalignment (strabismus), blur induced by unequal refractive error (anisometropia), and in some cases by form deprivation.
Although amblyopia is initially caused by abnormal visual input in infancy, once established, the visual deficit often remains when normal visual input has been restored using surgery and/or refractive correction. This is because amblyopia is the result of abnormal visual cortex development rather than a problem with the amblyopic eye itself4,5 . Amblyopia is characterized by both monocular and binocular deficits6,7 which include impaired visual acuity and poor or absent stereopsis respectively. The visual dysfunction in amblyopia is often associated with a strong suppression of the inputs from the amblyopic eye under binocular viewing conditions8. Recent work has indicated that suppression may play a central role in both the monocular and binocular deficits associated with amblyopia9,10 .
Current clinical tests for suppression tend to verify the presence or absence of suppression rather than giving a quantitative measurement of the degree of suppression. Here we describe a technique for measuring amblyopic suppression with a compact, portable device11,12 . The device consists of a laptop computer connected to a pair of virtual reality goggles. The novelty of the technique lies in the way we present visual stimuli to measure suppression. Stimuli are shown to the amblyopic eye at high contrast while the contrast of the stimuli shown to the non-amblyopic eye are varied. Patients perform a simple signal/noise task that allows for a precise measurement of the strength of excitatory binocular interactions. The contrast offset at which neither eye has a performance advantage is a measure of the "balance point" and is a direct measure of suppression. This technique has been validated psychophysically both in control13,14 and patient6,9,11 populations.
In addition to measuring suppression this technique also forms the basis of a novel form of treatment to decrease suppression over time and improve binocular and often monocular function in adult patients with amblyopia12,15,16 . This new treatment approach can be deployed either on the goggle system described above or on a specially modified iPod touch device15.

Amblyopia is a developmental disorder of the visual cortex that is often accompanied by strong suppression of one eye. We present a new technique for measuring and treating interocular suppression in patients with amblyopia that can be deployed using virtual reality goggles or a portable iPod Touch device.

La misurazione e trattamento di soppressione in Ambliopia

Amblyopia, a developmental disorder of the visual cortex, is one of the leading causes of visual dysfunction in the working age population. Current ...

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

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

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

Utilizzando quantitativa real-time PCR per la determinazione cellulare attecchimento dei donatori in un modello murino competitivo trapianto di midollo osseo

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

Myocardial Infarction and Functional Outcome Assessment in Pigs

Introduction of newly discovered cardiovascular therapeutics into first-in-man trials depends on a strictly regulated ethical and legal roadmap. One important prerequisite is a good understanding of all safety and efficacy aspects obtained in a large animal model that validly reflect the human scenario of myocardial infarction (MI). Pigs are widely used in this regard since their cardiac size, hemodynamics, and coronary anatomy are close to that of humans. Here, we present an effective protocol for using the porcine MI model using a closed-chest coronary balloon occlusion of the left anterior descending artery (LAD), followed by reperfusion. This approach is based on 90 min of myocardial ischemia, inducing large left ventricle infarction of the anterior, septal and inferoseptal walls. Furthermore, we present protocols for various measures of outcome that provide a wide range of information on the heart, such as cardiac systolic and diastolic function, hemodynamics, coronary flow velocity, microvascular resistance, and infarct size. This protocol can be easily tailored to meet study specific requirements for the validation of novel cardioregenerative biologics at different stages (i.e. directly after the acute ischemic insult, in the subacute setting or even in the chronic MI once scar formation has been completed). This model therefore provides a useful translational tool to study MI, subsequent adverse remodeling, and the potential of novel cardioregenerative agents.

This protocol describes the porcine myocardial infarction (MI) model using a 90 min closed-chest coronary balloon occlusion of the left anterior descending artery (LAD), followed by reperfusion. Furthermore, the protocol for several outcome parameters, such as cardiac function, hemodynamics, microvascular resistance, and infarct size, are also presented.

Infarto miocardico e funzionale Outcome Assessment in Pigs

Introduction of newly discovered cardiovascular therapeutics into first-in-man trials depends on a strictly regulated ethical and legal roadmap. One ...

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.

A Modified<em&gt; In vitro</em&gt; Invasion test per determinare il ruolo potenziale di ormoni, citochine e / o fattori di crescita nella mediazione Cancer Invasion cellulare

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

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.

Concentrarsi Formazione: Un test cellulare per determinare il potenziale oncogeno di un gene

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

Measurement of the Pressure-volume Curve in Mouse Lungs

In recent decades the mouse has become the primary animal model of a variety of lung diseases. In models of emphysema or fibrosis, the essential phenotypic changes are best assessed by measurement of the changes in lung elasticity. To best understand specific mechanisms underlying such pathologies in mice, it is essential to make functional measurements that can reflect the developing pathology. Although there are many ways to measure elasticity, the classical method is that of the total lung pressure-volume (PV) curve done over the whole range of lung volumes. This measurement has been made on adult lungs from nearly all mammalian species dating back almost 100 years, and such PV curves also played a major role in the discovery and understanding of the function of pulmonary surfactant in fetal lung development. Unfortunately, such total PV curves have not been widely reported in the mouse, despite the fact that they can provide useful information on the macroscopic effects of structural changes in the lung. Although partial PV curves measuring just the changes in lung volume are sometimes reported, without a measure of absolute volume, the nonlinear nature of the total PV curve makes these partial ones very difficult to interpret. In the present study, we describe a standardized way to measure the total PV curve. We have then tested the ability of these curves to detect changes in mouse lung structure in two common lung pathologies, emphysema and fibrosis. Results showed significant changes in several variables consistent with expected structural changes with these pathologies. This measurement of the lung PV curve in mice thus provides a straightforward means to monitor the progression of the pathophysiologic changes over time and the potential effect of therapeutic procedures.

Here we present a protocol to simply and reliably measure the lung pressure-volume curve in mice, showing that it is sufficiently sensitive to detect phenotypic parenchymal changes in two common lung pathologies, pulmonary fibrosis and emphysema. This metric provides a means to quantify the lung&#8217;s structural changes with developing pathology.

Misura della curva di pressione-volume in mouse polmoni

In recent decades the mouse has become the primary animal model of a variety of lung diseases. In models of emphysema or fibrosis, the essential ...

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.

Studiare cancro del pancreas staminali caratteristiche cellulari per lo sviluppo di nuove strategie di trattamento

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

A "Patient-Like" Orthotopic Syngeneic Mouse Model of Hepatocellular Carcinoma Metastasis

The majority of cancer-related deaths are caused by the metastasis of the cancer rather than the primary tumor itself. Yet, the underlying mechanisms of cancer metastasis are still unclear. Animal models are essential for elucidating the mechanisms and for evaluating novel strategies for the treatment of metastatic cancers. Here, an in-depth description of a &#8220;patient-like&#8221; orthotopic syngeneic mouse model for exploring the mechanisms of metastasis of solid organ tumors is provided. The survival surgical implantation of BNL 1ME A.7R.1 mouse hepatocellular carcinoma cells directly into the liver (the organ of origin) of the inbred wild-type immune competent laboratory mouse strain, BALB/c is described. The success and reproducibility of this methodology recommends it for widespread use in elucidating the biological mechanisms of solid organ cancer metastasis.

The metastatic spread of cancer is the major cause of cancer-related deaths. We provide an in-depth description of our survival surgery methodology for establishing a &#8220;patient-like&#8221; orthotopic syngeneic mouse model system for studying the mechanisms of metastasis in solid organ tumors.

A &quot;paziente-Like&quot; ortotopico Singenico modello murino della carcinoma epatocellulare Metastasi

The majority of cancer-related deaths are caused by the metastasis of the cancer rather than the primary tumor itself. Yet, the underlying mechanisms of ...

Isolation of Endothelial Progenitor Cells from Healthy Volunteers and Their Migratory Potential Influenced by Serum Samples After Cardiac Surgery

Endothelial progenitor cells (EPCs) are recruited from the bone marrow under pathological conditions like hypoxia and are crucially involved in the neovascularization of ischemic tissues. The origin, classification and characterization of EPCs are complex; notwithstanding, two prominent sub-types of EPCs have been established: so-called &#34;early&#34; EPCs (subsequently referred to as early-EPCs) and late-outgrowth EPCs (late-EPCs). They can be classified by biological properties as well as by their appearance during in vitro culture. While &#34;early&#34; EPCs appear in less than a week after culture of peripheral blood-derived mononuclear cells in EC-specific media, late-outgrowth EPCs can be found after 2-3 weeks. Late-outgrowth EPCs have been recognized to be directly involved in neovascularization, mainly through their ability to differentiate into mature endothelial cells, whereas &#34;early&#34; EPCs express various angiogenic factors as endogenous cargo to promote angiogenesis in a paracrine manner. During myocardial ischemia/reperfusion (I/R), various factors control the homing of EPCs to regions of blood vessel formation.
Macrophage migration inhibitory factor (MIF) is a chemokine-like pro-inflammatory and ubiquitously expressed cytokine and was recently described to function as key regulator of EPCs migration at physiological concentrations1. Interestingly, MIF is stored in intracellular pools and can rapidly be released into the blood stream after several stimuli (e.g. myocardial infarction). 
This protocol describes a method for the reliable isolation and culture of early-EPCs from adult human peripheral blood based on CD34-positive selection with subsequent culture in medium containing endothelial growth factors on fibronectin-coated plates for use in in vitro migration assays against serum samples of cardiac surgical patients. Furthermore, the migratory influence of MIF on chemotaxis of EPCs compared to other well-known angiogenesis-stimulating cytokines is demonstrated.

Endothelial progenitor cells (EPCs) are crucially involved in the neovascularization of ischemic tissues. This method describes the isolation of human EPCs from peripheral blood, as well as the identification of their migratory potential against serum samples of cardiac surgical patients.

L&#39;isolamento di cellule progenitrici endoteliali da volontari sani e il loro potenziale migratori influenzato dal siero campioni dopo cardiochirurgia

Endothelial progenitor cells (EPCs) are recruited from the bone marrow under pathological conditions like hypoxia and are crucially involved in the ...