Gli autori desiderano ringraziare biolitec Research GmbH (Jena, Germania) per averci gentilmente fornito con la formulazione liposomiale mTHPC, con un ringraziamento speciale a Susanna Gräfe e Arno Wiehe per il loro aiuto e la competenza tecnica. Vorremmo anche ringraziare Kerstin Reidy, che ha generato una gran parte dei risultati ed è stato corresponsabile per la sua pubblicazione 11. Questo lavoro è stato sostenuto da sovvenzioni dal Schweizerischer Verein Balgrist, dell&#39;Università di Zurigo, il Krebsliga Zurigo così come da una sovvenzione da Walter L. e Johanna Lupo Foundation, Zurigo, Svizzera e una sovvenzione da EuroNanoMed ERA-NET / SNF svizzera National Science Foundation 31NM30-131004/1. Questo lavoro è stato supportato anche dal programma (altamente specializzati Medicina) per muscoloscheletrico Oncologia del Canton Zurigo HSM.

1. Confronto tra l&#39;assorbimento del mTHPC nei rispettivi basso e altamente metastatico HOS e 143B OS Linee Cellulari <ol><li> Preparare terreno di coltura contenente DMEM, Ham F12, e siero fetale di vitello inattivato al calore in un rapporto 4.5:4.5:1. Nota: La formulazione liposomiale del PS mTHPC è stato disciolto in acqua ad una concentrazione finale di 1,5 mg / ml mTHPC. </li><li> Tavola 0.2 x 10 6 HOS e cellule 143B / pozzetto in piastre da 6 pozzetti (triplicato per ogni condizione), e lasciare che le cellule aderiscono durante la notte. Nota: il numero deve essere regolato per linee di cellule singole. Una confluenza del 80-90% è più adatto al momento dell&#39;esperimento. </li><li> Il giorno seguente, incubare le cellule con una concentrazione fissa di mTHPC per diversi periodi di tempo (assorbimento dipendente dal tempo), o con concentrazioni crescenti di mTHPC durante un periodo di tempo fisso (dose assorbimento dipendente). </li><li> Incubare le cellule con mTHPC per tempo specifico points o concentrazioni di mTHPC. Nota: In questo studio, sia l&#39;HOS e linee cellulari 143B sono state incubate con 0,6 ug / ml mTHPC per 0, 2,5, 5 o 10 ore, o con 0, 0,6, 2,5, e 10 ug / ml mTHPC per 5 ore. I periodi di tempo richiesti e dosaggi possono variare a seconda della linea cellulare utilizzata. </li><li> Ricordatevi di lavorare sempre al buio o in condizioni di luce soffusa per evitare l&#39;esposizione a luce diretta delle cellule. </li><li> Dopo incubazione delle cellule alle condizioni indicate, aspirare il terreno e lavare le cellule tre volte con PBS. Successivamente, staccare le cellule con 0,5 ml di tripsina / EDTA e contare le cellule. </li><li> Dopo distacco, centrifugare le cellule a 400 xg per 5 min, aspirare il terreno e risospendere le cellule in PBS ad una densità finale di 200.000 cellule / ml. </li><li> Pipettare 100 ml di sospensione cellulare ottenuta (ossia 20.000 cellule) in una piastra a 96 pozzetti e misurare la fluorescenza di queste cellule in uno spettrofotometro a fluorescenza. L&#39;impostaziones per mTHPC misure di fluorescenza sono: 417 nm per l&#39;eccitazione e 652 nm per l&#39;emissione. </li><li> Per calcolare la quantità di mTHPC internalizzato per cella, normalizzare l&#39;unità di fluorescenza relativa (RFU) per il numero di cellule e volume cellulare come segue: </li><li> Preparare una curva standard utilizzando diverse concentrazioni di mTHPC in PBS 0-4 mcg / ml (misure uso triplice copia). Pipettare 100 ml di ogni diluizione in una piastra a 96 pozzetti e misurare la fluorescenza dei pozzetti usando le impostazioni descritte sotto passo 1.6. </li><li> Dividere la RFU (ottenuto per 20.000 cellule) dalla pendenza della curva standard lineare di mTHPC, che rappresenta la concentrazione di mTHPC (in mg / ml) nel pozzo. </li><li> Dividere questa concentrazione mTHPC per 10 per ottenere la quantità totale di mTHPC in un pozzetto (in mg, che rappresenta 100 microlitri di sospensione cellulare) e dividere questo valore per il volume di 20.000 cellule. </li><li> Calcolare il volume con la formula per una sfera: (4/3 x π) xr 3. Ottenere il raggio r misurando il diametro di 20 cellule trypsinized al microscopio, e dividendo questo valore per 2. </li><li> Infine, normalizzare tutti i valori a quelli ottenuti con cellule HOS dopo 10 ore di incubazione (dose assorbimento dipendente) o trattati con 10 mg / ml mTHPC (uptake funzione del tempo), che sono stati fissati al 100%. </li></ol> 2. Misurazione della fototossicità di PS In Vitro <ol><li> Seed 3.000 cellule / pozzetto in una piastra a 96 pozzetti (triplicato per ciascuna concentrazione di mTHPC usati) e farli aderire durante la notte. Analogamente preparare una piastra da 96 pozzetti supplementari e trattare le cellule come descritto di seguito, ma poi messo da parte per l&#39;imaging a contrasto di fase. Nota: il numero deve essere regolata per ogni linea singola cella. Una confluenza del 50-60% al momento dell&#39;esperimento è ideale. <ol><li> Tenere a mente per aggiungere il corrispondente controllo di tossicità scuro di cellule per ciascuna delle concentrazioni mTHPC. Ilse sono cellule che saranno incubate in assenza o in presenza di concentrazioni selezionati di mTHPC, ma non si illuminerà. </li></ol></li><li> Il giorno seguente, incubare le cellule con differenti concentrazioni di mTHPC (0, 0,0001, 0,001, 0,01, 0,03, 0,075, 0,15, 0,3, 0,6, 1,25, 2,5, 5 e 10 mg / ml) a seconda delle linee cellulari e tenerli al buio per 5 ore. <ol><li> Fare riferimento alla sezione 1.3.2 Nota: Il tempo di incubazione prima illuminazione dipende dalla linea cellulare e del PS usato, quindi è consigliabile per testare diverse concentrazioni e tempi diversi in esperimenti separati. </li></ol></li><li> Dopo l&#39;incubazione per il periodo di tempo indicato, lavare le cellule due volte con PBS e aggiungere nuovo terreno fresco, senza mTHPC. </li><li> Illuminare le cellule con un diodo laser 652 nm, specifico per lo spettro di assorbimento mTHPC (vedi Figura 1). <ol><li> Impostare il laser a 21.88 mW / cm 2 potenza ad una altezza di 13,5 centimetri distaSNO dalle cellule, al fine di ottenere una dose di energia 5 J / cm 2. Illuminare le cellule per 230 sec. Non illuminare le cellule di controllo tossicità scuri (con e senza mTHPC). Nota: indossare sempre occhiali per proteggere gli occhi dalla luce laser utilizzato per l&#39;eccitazione del PS. </li></ol></li><li> Dopo l&#39;illuminazione, mantenere le celle al buio a 37 ° C per 24 ore. Successivamente, aggiungere acqua tetrazolio solubile (WST-1) reattivo (10 μl/100 ml di media). </li><li> Tre ore dopo l&#39;aggiunta del reagente WST-1, misurare l&#39;assorbanza dei singoli pozzetti della piastra a 96 pozzetti a 415 nm. </li><li> Per calcolare la percentuale di cellule sopravvissute, impostare la media dei valori ottenuti per le cellule trattate mTHPC non per ciascuna condizione al 100% (cioè illuminati, senza mTHPC e nonilluminated senza mTHPC). </li></ol> 3. Stima del numero di cellule contando cellulare <ol><li> Seed 20.000 cellule / noill in una piastra a 24 pozzetti e farli aderire durante la notte. </li><li> Incubare le cellule per 5 ore con mTHPC (0,001, 0,003, 0,15, 0,6, e 1,25 mg / ml) e illuminare come descritto sopra. </li><li> Raccogliere il mezzo, lavare le cellule una volta con PBS, li trypsinize e alla loro raccolta per centrifugazione a 400 xg per 5 min. </li><li> Dopo centrifugazione, aspirare il terreno e risospendere le cellule in 200 ml di terreno fresco. </li><li> Contare le cellule in una camera di Neubauer. </li></ol>

<ol>
	<li>Juarranz, A., Jaen, P., Sanz-Rodriguez, F., Cuevas, J., Gonzalez, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Photodynamic+therapy+of+cancer.+Basic+principles+and+applications.">Photodynamic therapy of cancer. Basic principles and applications.</a> Clin. Transl. Oncol. 10, 148-154 (2008).</li><li>Agostinis, P., 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=Photodynamic+therapy+of+cancer:+an+update.">Photodynamic therapy of cancer: an update.</a> CA Cancer. 61, 250-281 (2011).</li><li>D'Adamo, D. R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Appraising+the+current+role+of+chemotherapy+for+the+treatment+of+sarcoma.">Appraising the current role of chemotherapy for the treatment of sarcoma.</a> Semin. Oncol. 38 Suppl 3, 19-29 (2011).</li><li>Allison, D. 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=A+meta-analysis+of+osteosarcoma+outcomes+in+the+modern+medical+era.">A meta-analysis of osteosarcoma outcomes in the modern medical era.</a> Sarcoma. , (2012).</li><li>Anninga, J. K., 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=Chemotherapeutic+adjuvant+treatment+for+osteosarcoma:+where+do+we+stand.">Chemotherapeutic adjuvant treatment for osteosarcoma: where do we stand.</a> Eur. J. Cancer. 47, 2431-2445 (2011).</li><li>Bacci, G., 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=Pattern+of+relapse+in+patients+with+osteosarcoma+of+the+extremities+treated+with+neoadjuvant+chemotherapy.">Pattern of relapse in patients with osteosarcoma of the extremities treated with neoadjuvant chemotherapy.</a> Eur. J. Cancer. 37, 32-38 (2001).</li><li>Briccoli, A., 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=Resection+of+recurrent+pulmonary+metastases+in+patients+with+osteosarcoma.">Resection of recurrent pulmonary metastases in patients with osteosarcoma.</a> Cancer. 104, 1721-1725 (2005).</li><li>Milla Sanabria, L., 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=Direct+and+indirect+photodynamic+therapy+effects+on+the+cellular+and+molecular+components+of+the+tumor+microenvironment.">Direct and indirect photodynamic therapy effects on the cellular and molecular components of the tumor microenvironment.</a> Biochim. Biophys. Acta. 1835, 36-45 (2013).</li><li>Mitra, S., Foster, T. H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Photophysical+parameters,+photosensitizer+retention+and+tissue+optical+properties+completely+account+for+the+higher+photodynamic+efficacy+of+meso-tetra-hydroxyphenyl-chlorin+vs+Photofrin.">Photophysical parameters, photosensitizer retention and tissue optical properties completely account for the higher photodynamic efficacy of meso-tetra-hydroxyphenyl-chlorin vs Photofrin.</a> Photochem. Photobiol. 81, 849-859 (2005).</li><li>Ma, L., Moan, J., Berg, K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Evaluation+of+a+new+photosensitizer,+meso-tetra-hydroxyphenyl-chlorin,+for+use+in+photodynamic+therapy:+a+comparison+of+its+photobiological+properties+with+those+of+two+other+photosensitizers.">Evaluation of a new photosensitizer, meso-tetra-hydroxyphenyl-chlorin, for use in photodynamic therapy: a comparison of its photobiological properties with those of two other photosensitizers.</a> Int. J. Cancer. 57, 883-888 (1994).</li><li>Reidy, K., Campanile, C., Muff, R., Born, W., Fuchs, B. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=mTHPC-mediated+photodynamic+therapy+is+effective+in+the+metastatic+human+143B+osteosarcoma+cells.">mTHPC-mediated photodynamic therapy is effective in the metastatic human 143B osteosarcoma cells.</a> Photochem. Photobiol. 88, 721-727 (2012).</li><li>Triesscheijn, M., Ruevekamp, M., Aalders, M., Baas, P., Stewart, F. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Comparative+sensitivity+of+microvascular+endothelial+cells,+fibroblasts+and+tumor+cells+after+in+vitro+photodynamic+therapy+with+meso-tetra-hydroxyphenyl-chlorin.">Comparative sensitivity of microvascular endothelial cells, fibroblasts and tumor cells after in vitro photodynamic therapy with meso-tetra-hydroxyphenyl-chlorin.</a> Photochem. Photobiol. 80, 236-241 (2004).</li><li>Triesscheijn, M., Baas, P., Schellens, J. H., Stewart, F. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Photodynamic+therapy+in+oncology.">Photodynamic therapy in oncology.</a> Oncologist. 11, 1034-1044 (2006).</li><li>Burch, S., 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=Treatment+of+canine+osseous+tumors+with+photodynamic+therapy:+a+pilot+study.">Treatment of canine osseous tumors with photodynamic therapy: a pilot study.</a> Clin. Orthop. Relat. Res. 467, 1028-1034 (2009).</li></ol>

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Per ottenere citotossicità ottimale in risposta a PDT, è fondamentale scegliere le impostazioni di luce laser destra e tempi di incubazione. Le procedure qui descritte sono coerenti ed efficienti per determinare PS assorbimento e quantificare citotossicità PDT indotta in vitro. Utilizzando le specifiche lunghezze d&#39;onda di assorbimento della PS mTHPC, il PS assorbimento cellulare può essere determinato in modo diretto, e il PS può essere attivato per generare citotossici specie reattive dell&#39;ossige...

Lo stato odierno del trattamento arte di osteosarcoma (OS), un tumore osseo primario, comprende una combinazione di chemioterapia neo adiuvante e chirurgia. Questo regime terapeutico rivelato un aumento del tasso di sopravvivenza dei pazienti con malattia localizzata da circa il 20% prima dell&#39;uso della chemioterapia, per attualmente tra 60-70% 3, 4. Tuttavia, negli ultimi due decenni, la sopravvivenza complessiva dei pazienti con malattia del sistema operativo locale ha plateaued 4, 5. Inoltre, il 30-40% di questi pazienti ricaduta entro 3 anni dopo la diagnosi e pazienti con malattia metastatica continuare ad avere una scarsa sopravvivenza del 20-30% 4, 6, 7. Per migliorare l&#39;esito di questi pazienti, nuove strategie terapeutiche devono essere sviluppate. La terapia fotodinamica (PDT), una terapia antitumorale piuttosto romanzo, utilizza la luce di una specifica lunghezza d&#39;onda di eccitazione di un photosensitizer (PS), che si accumula nelle cellule tumorali dopo l&#39;iniezione nel flusso sanguigno. Luce laser di eccitazione del PS genera radicali dell&#39;ossigeno in presenza di ossigeno, che inducono reazione citotossica nelle cellule tumorali e cellule morte. Oltre a questo meccanismo principale, due ulteriori PDT evocato processi biologici contribuiscono alla crescita del tumore ridotta: PDT provoca vasocostrizione e la formazione di trombi del microcircolo tumore e, di conseguenza, ipossia e anossia locale all&#39;interno del tumore, con conseguente tumore infarto. Infine, PDT ferito e cellule tumorali muoiono innescare una risposta immunitaria locale, una caratteristica piuttosto unica di PDT. Ciò comporta il sistema del complemento e l&#39;attivazione delle cellule presentanti l&#39;antigene dendritiche 8. Così, si creano le condizioni per la presentazione di antigeni tumorali con conseguente attivazione di cellule linfoidi, portando a tumore immunità specifica. Finora, PDT è stato usato per trattare diversi tipi di tumori dei tessuti molli e hyperplasia, quali cheratosi attinica, esofago di Barrett, tumori endobronchiali, cancro della vescica, carcinomi a cellule basali, e il trattamento palliativo della testa e del collo 2. Il trattamento è noto per indurre locale, necrosi larga scala con solo pochi effetti collaterali, e quindi ha il potenziale per eradicare selettivamente tessuto tumorale. Nonostante questi vantaggi, l&#39;applicazione di PDT rimane tecnicamente più impegnativo rispetto alla somministrazione di farmaci chemioterapici. Al fine di raggiungere la massima efficacia, la concentrazione PS, tempo di esposizione alla luce e totale trasferimento di energia luminosa devono essere ottimizzate. Questo può essere fatto in esperimenti in vivo, ma, a causa del gran numero relativo di parametri che devono essere ottimizzate, è più efficiente per determinare inizialmente condizioni ottimali in vitro. Negli esperimenti descritti di seguito, abbiamo testato l&#39;efficacia in vitro di PDT utilizzando il PS 5,10,15,20-tetrakis (meta-idrossifenil) chlOrin, abbreviato mTHPC (Figura 1A). mTHPC è il principio attivo contenuto nel medicinale Foscan, che viene attualmente utilizzato in clinica per il trattamento palliativo del carcinoma della testa e del collo. Si tratta di uno dei più potenti PS, inducendo danno cellulare massiccia già a basse concentrazioni, ed è stato dimostrato di essere superiore ad altri PS in termini di penetrazione nel tessuto 9, 10. Il suo spettro di assorbimento della luce (Figura 1B) presenta due picchi prominenti, una a 417 nm ed una seconda a 652 nm, che sono utilizzati per la localizzazione del tessuto di accumulare PS e per l&#39;induzione PDT, rispettivamente. Attualmente, una formulazione liposomiale per mTHPC è in fase di sviluppo. Qui, descriviamo le procedure per quantificare l&#39;assorbimento di questa formulazione liposomiale, e per eseguire PDT in due linee di cellule del sistema operativo umani, la bassa HOS metastatico e le alte cellule metastatiche 143B. Alcuni dei dati presentati qui sono stati segnalati in precedenza 11. The approccio qui descritto permette di studiare l&#39;effetto di un fenotipo metastatico sul PDT efficacia. 143B cellule, ortotopicamente iniettate nelle arti posteriori del sistema immunitario topi SCID con deficit causano tumori intratibial metastatizzanti primari, un modello mimando la malattia metastasi umana. Così, gli esperimenti proposti in vitro sono perfettamente adatti per valutare le impostazioni ottimali PDT per essere successivamente utilizzati in esperimenti in vivo.

<table border="0" cellpadding="0" cellspacing="0" width="955">
	<colgroup>
		<col />
		<col />
		<col />
		<col />
	</colgroup>
	<tbody>
		<tr height="21">
			<td height="21" style="height:21px;width:291px;">DMEM</td>
			<td style="width:251px;">PAA GmbH, Freiburg, Germany</td>
			<td style="width:127px;">E15-883</td>
			<td style="width:287px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:291px;">HAM F12</td>
			<td>PAA GmbH, Freiburg, Germany</td>
			<td style="width:127px;">E15-817</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:291px;">heat-inactivated fetal calf serum</td>
			<td>GIBCO, Basel, Switzerland</td>
			<td style="width:127px;">10500-064</td>
			<td></td>
		</tr>
		<tr height="147">
			<td height="147" style="height:147px;width:291px;">mTHPC</td>
			<td style="width:251px;">biolitec research GmbH, Jena, Germany</td>
			<td style="width:127px;"></td>
			<td style="width:287px;">As this liposomal formulation is originating from R &#38; D 
			no catalogue number is available at the moment. Stock: 1.5mg/ml; provided in a 9:1 mixture of dipalmitoylphosphatidylcholine (DPPC) and dipalmitoylphosphatidylglycerol (DPPG; &#62;99% purity)</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Spectramax Gemini XS plate reader</td>
			<td style="width:251px;">Molecular Devices, Sunnyvale, CA</td>
			<td style="width:127px;">ID# 861</td>
			<td></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:291px;">Microscope Zeiss Observer.Z1</td>
			<td style="width:251px;">Axio Observer, Axio Vision Release 4.6.3 SP1, Jena Germany</td>
			<td style="width:127px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:291px;">Ceralas PDT 652 nm Laser</td>
			<td style="width:251px;">Biolitec AG, Jena, Germany</td>
			<td style="width:127px;">LD652nm2W400u</td>
			<td></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:291px;">Water-soluble tetrazolium (WST) reagent</td>
			<td style="width:251px;">Roche Diagnostics AG, Rotkreuz, Switzerland</td>
			<td style="width:127px;">1644807</td>
			<td></td>
		</tr>
	</tbody>
</table>

cytotoxic efficacy of photodynamic therapy in osteosarcoma cells in vitro

Negli ultimi anni, vi è stata la difficoltà di trovare terapie più efficaci contro il cancro con meno effetti collaterali sistemici. Pertanto Terapia Fotodinamica è un nuovo approccio per un trattamento selettivo più del tumore. La terapia fotodinamica (PDT) che fa uso di un fotosensibilizzatore tossico (PS), il quale, dopo attivazione con luce di una specifica lunghezza d&#39;onda, in presenza di ossigeno, genera radicali dell&#39;ossigeno che suscitano una risposta citotossica 1. Nonostante la sua approvazione quasi vent&#39;anni fa dalla FDA, PDT è oggi utilizzato solo per il trattamento di un numero limitato di tipi di cancro (pelle, della vescica) e le malattie nononcological (psoriasi, cheratosi attinica) 2. Il principale vantaggio della PDT è la capacità di eseguire un trattamento locale, che previene gli effetti collaterali sistemici. Inoltre, permette il trattamento di tumori in siti delicati (ad esempio attorno nervi o vasi sanguigni). Qui, un intraoperatapplicazione ive di PDT è considerato in osteosarcoma (OS), un tumore dell&#39;osso, per indirizzare satelliti tumorali primari lasciati nel tumore tessuto circostante dopo la resezione chirurgica del tumore. Il trattamento mira a ridurre il numero di recidive e di ridurre il rischio di (postoperatorio) metastasi. Nel presente studio, presentiamo in vitro procedure PDT stabilire le impostazioni ottimali PDT per il trattamento efficace di linee cellulari OS diffusi che vengono utilizzati per riprodurre la malattia umana in modelli murini OS intratibial consolidate. L&#39;assorbimento del PS mTHPC è stato esaminato con uno spettrofotometro e fototossicità è stato provocato con la luce laser di eccitazione di mTHPC a 652 nm per indurre la morte cellulare valutata con WST-1 test e il conteggio delle cellule sopravvissute. Le tecniche consolidate ci consentono di definire le impostazioni ottimali PDT per futuri studi in modelli animali. Sono uno strumento semplice e rapido per la valutazione dell&#39;efficacia di PDT <em&gt; In vitro prima di un&#39;applicazione in vivo.

Con le tecniche qui riportate, abbiamo studiato a base di mTHPC PDT in cellule umane del sistema operativo. In primo luogo, l&#39;assorbimento dipendente dal tempo e dose di mTHPC è stato studiato nel partire HOS metastatico e nelle linee cellulari 143B OS altamente metastatiche. mTHPC assorbimento può essere valutata misurando la fluorescenza di mTHPC con uno spettrofotometro a fluorescenza (Figura 2, riprodotto con il permesso Reidy et al. 11). Figura 2A illustra...

Watch this Scientific Journal Video about Cytotoxic Efficacy of Photodynamic Therapy in Osteosarcoma Cells In Vitro at JoVE.com

Cytotoxic Efficacy of Photodynamic Therapy in Osteosarcoma Cells In Vitro

Il protocollo qui riportato permette di valutare l&#39;efficacia della terapia fotodinamica (PDT) in linee cellulari e l&#39;ottimizzazione delle impostazioni PDT prima di applicare la terapia in modelli animali.

Citotossico Efficacia della terapia fotodinamica in cellule di osteosarcoma<em&gt; In Vitro</em

In recent years, there has been the difficulty in finding more effective therapies against cancer with less systemic side effects. Therefore Photodynamic ...

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Cytotoxic Efficacy of Photodynamic Therapy in Osteosarcoma Cells In Vitro

12.7K Views.  Balgrist University Hospital, Zurich, Switzerland.  Il protocollo qui riportato permette di valutare l'efficacia della terapia fotodinamica (PDT) in linee cellulari e l'ottimizzazione delle impostazioni PDT prima di applicare la terapia in modelli animali. 

Video: Cytotoxic Efficacy of Photodynamic Therapy in Osteosarcoma Cells In Vitro

Subretinal Injection of Gene Therapy Vectors and Stem Cells in the Perinatal Mouse Eye

The loss of sight affects approximately 3.4 million people in the United States and is expected to increase in the upcoming years.1 Recently, gene therapy and stem cell transplantations have become key therapeutic tools for treating blindness resulting from retinal degenerative diseases. Several forms of autologous transplantation for age-related macular degeneration (AMD), such as iris pigment epithelial cell transplantation, have generated encouraging results, and human clinical trials have begun for other forms of gene and stem cell therapies.2 These include RPE65 gene replacement therapy in patients with Leber's congenital amaurosis and an RPE cell transplantation using human embryonic stem (ES) cells in Stargardt's disease.3-4 Now that there are gene therapy vectors and stem cells available for treating patients with retinal diseases, it is important to verify these potential therapies in animal models before applying them in human studies. The mouse has become an important scientific model for testing the therapeutic efficacy of gene therapy vectors and stem cell transplantation in the eye.5-8 In this video article, we present a technique to inject gene therapy vectors or stem cells into the subretinal space of the mouse eye while minimizing damage to the surrounding tissue.

This surgical technique illustrates the injection of gene therapy vectors and stem cells into the subretinal space of the mouse eye.

Iniezione sottoretinico di vettori di terapia genica e cellule staminali nel Eye mouse

The loss of sight affects approximately 3.4 million people in the United States and is expected to increase in the upcoming years.1 Recently, gene therapy ...

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Medicina

In vitro Enrichment of Ovarian Cancer Tumor-initiating Cells

Evidence suggests that small subpopulations of tumor cells maintain a unique self-renewing and differentiation capacity and may be responsible for tumor initiation and/or relapse. Clarifying the mechanisms by which these tumor-initiating cells (TICs) support tumor formation and progression could lead to the development of clinically favorable therapies. Ovarian cancer is a heterogeneous and highly recurrent disease. Recent studies suggest TICs may play an important role in disease biology. We have identified culture conditions that enrich for TICs from ovarian cancer cell lines. Growing either adherent cells or non-adherent &#8216;floater&#8217; cells in a low attachment plate with serum free media in the presence of growth factors supports the propagation of ovarian cancer TICs with stem cell markers (CD133 and ALDH activity) and increased tumorigenicity without the need to physically separate the TICs from other cell types within the culture. Although the presence of floater cells is not common for all cell lines, this population of cells with innate low adherence may have high tumorigenic potential.Compared to adherent cells grown in the presence of serum, TICs readily form spheres, are significantly more tumorigenic in mice, and express putative stem cell markers. The conditions are easy to establish in a timely manner and can be used to study signaling pathways important for maintaining stem characteristics, and to identify drugs or combinations of drugs targeting TICs. The culture conditions described herein are applicable for a variety of ovarian cancer cells of epithelial origin and will be critical in providing new information about the role of TICs in tumor initiation, progression, and relapse.

In vitro Enrichment of Ovarian Cancer Tumor-initiating Cells

Tumor-initiating cells (TICs) may represent a viable therapeutic target for the treatment of ovarian cancer, a highly recurrent and fatal disease. We present a protocol for culture conditions that enrich for this highly tumorigenic population of cells.

In Arricchimento vitro di Ovarian Cancer Cells-tumorali avvio

Evidence suggests that small subpopulations of tumor cells maintain a unique self-renewing and differentiation capacity and may be responsible for tumor ...

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 ...

Depletion of Mouse Cells from Human Tumor Xenografts Significantly Improves Downstream Analysis of Target Cells

The use of in vitro cell line models for cancer research has been a useful tool. However, it has been shown that these models fail to reliably mimic patient tumors in different assays1. Human tumor xenografts represent the gold standard with respect to tumor biology, drug discovery, and metastasis research 2-4. Tumor xenografts can be derived from different types of material like tumor cell lines, tumor tissue from primary patient tumors4 or serially transplanted tumors. When propagated in vivo, xenografted tissue is infiltrated and vascularized by cells of mouse origin. Multiple factors such as the tumor entity, the origin of xenografted material, growth rate and region of transplantation influence the composition and the amount of mouse cells present in tumor xenografts. However, even when these factors are kept constant, the degree of mouse cell contamination is highly variable.
Contaminating mouse cells significantly impair downstream analyses of human tumor xenografts. As mouse fibroblasts show high plating efficacies and proliferation rates, they tend to overgrow cultures of human tumor cells, especially slowly proliferating subpopulations. Mouse cell derived DNA, mRNA, and protein components can bias downstream gene expression analysis, next-generation sequencing, as well as proteome analysis 5. To overcome these limitations, we have developed a fast and easy method to isolate untouched human tumor cells from xenografted tumor tissue. This procedure is based on the comprehensive depletion of cells of mouse origin by combining automated tissue dissociation with the benchtop tissue dissociator and magnetic cell sorting. Here, we demonstrate that human target cells can be can be obtained with purities higher than 96% within less than 20 min independent of the tumor type.

Human tumor xenografts are vascularized and infiltrated by cells of mouse origin during the growth phase in vivo. To circumvent the bias caused by these contaminating cells during downstream analysis, we developed a method allowing for comprehensive depletion of all mouse cells by magnetic cell sorting.

L&#39;esaurimento delle cellule di topo da xenotrapianti tumorali umani migliora in modo significativo Analisi A valle delle cellule bersaglio

The use of in vitro cell line models for cancer research has been a useful tool. However, it has been shown that these models fail to reliably mimic ...

Forskolin-induced Swelling in Intestinal Organoids: An In Vitro Assay for Assessing Drug Response in Cystic Fibrosis Patients

Recently-developed cystic fibrosis transmembrane conductance regulator (CFTR)-modulating drugs correct surface expression and/or function of the mutant CFTR channel in subjects with cystic fibrosis (CF). Identification of subjects that may benefit from these drugs is challenging because of the extensive heterogeneity of CFTR mutations, as well as other unknown factors that contribute to individual drug efficacy. Here, we describe a simple and relatively rapid assay for measuring individual CFTR function and response to CFTR modulators in vitro. Three dimensional (3D) epithelial organoids are grown from rectal biopsies in standard organoid medium. Once established, the organoids can be bio-banked for future analysis. For the assay, 30-80 organoids are seeded in 96-well plates in basement membrane matrix and are then exposed to drugs. One day later, the organoids are stained with calcein green, and forskolin-induced swelling is monitored by confocal live cell microscopy at 37 &#176;C. Forskolin-induced swelling is fully CFTR-dependent and is sufficiently sensitive and precise to allow for discrimination between the drug responses of individuals with different and even identical CFTR mutations. In vitro swell responses correlate with the clinical response to therapy. This assay provides a cost-effective approach for the identification of drug-responsive individuals, independent of their CFTR mutations. It may also be instrumental in the development of future CFTR modulators.

Forskolin-induced Swelling in Intestinal Organoids: An In Vitro Assay for Assessing Drug Response in Cystic Fibrosis Patients

This protocol describes an assay for measuring CFTR function and CFTR modulator responses in cultured tissue from subjects with cystic fibrosis (CF). Biopsy-derived intestinal organoids swell in a cAMP-driven fashion, a response that is defective (or strongly reduced) in CF organoids and can be restored by exposure to CFTR modulators.

Forskolin indotta Gonfiore intestinale organoidi: An<em&gt; In Vitro</em&gt; Test per la valutazione della risposta farmacologica nella fibrosi cistica pazienti

Recently-developed cystic fibrosis transmembrane conductance regulator (CFTR)-modulating drugs correct surface expression and/or function of the mutant ...

Preparation and In Vitro Characterization of Magnetized miR-modified Endothelial Cells

To date, the available surgical and pharmacological treatments for cardiovascular diseases (CVD) are limited and often palliative. At the same time, gene and cell therapies are highly promising alternative approaches for CVD treatment. However, the broad clinical application of gene therapy is greatly limited by the lack of suitable gene delivery systems. The development of appropriate gene delivery vectors can provide a solution to current challenges in cell therapy. In particular, existing drawbacks, such as limited efficiency and low cell retention in the injured organ, could be overcome by appropriate cell engineering (i.e., genetic) prior to transplantation. The presented protocol describes the efficient and safe transient modification of endothelial cells using a polyethyleneimine superparamagnetic magnetic nanoparticle (PEI/MNP)-based delivery vector. Also, the algorithm and methods for cell characterization are defined. The successful intracellular delivery of microRNA (miR) into human umbilical vein endothelial cells (HUVECs) has been achieved without affecting cell viability, functionality, or intercellular communication. Moreover, this approach was proven to cause a strong functional effect in introduced exogenous miR. Importantly, the application of this MNP-based vector ensures cell magnetization, with accompanying possibilities of magnetic targeting and non-invasive MRI tracing. This may provide a basis for magnetically guided, genetically engineered cell therapeutics that can be monitored non-invasively with MRI.

Preparation and In Vitro Characterization of Magnetized miR-modified Endothelial Cells

This manuscript describes the efficient, non-viral delivery of miR to endothelial cells by a PEI/MNP vector and their magnetization. Thus, in addition to genetic modification, this approach allows for magnetic cell guidance and MRI detectability. The technique can be used to improve the characteristics of therapeutic cell products.

preparazione e<em&gt; In Vitro</em&gt; Caratterizzazione di magnetizzato miR-modificato cellule endoteliali

To date, the available surgical and pharmacological treatments for cardiovascular diseases (CVD) are limited and often palliative. At the same time, gene ...

A Method for Quantifying Upper Limb Performance in Daily Life Using Accelerometers

A key reason for referral to rehabilitation services after stroke and other neurological conditions is to improve one's ability to function in daily life. It has become important to measure a person's activities in daily life, and not just measure their capacity for activity in the structured environment of a clinic or laboratory. A wearable sensor that is now enabling measurement of daily movement is the accelerometer. Accelerometers are commercially-available devices resembling large wrist watches that can be worn throughout the day. Data from accelerometers can quantify how the limbs are engaged to perform activities in peoples' homes and communities. This report describes a methodology to collect accelerometry data and turn it into clinically-relevant information. First, data are collected by having the participant wear two accelerometers (one on each wrist) for 24 h or longer. The accelerometry data are then downloaded and processed to produce four different variables that describe key aspects of upper limb activity in daily life: hours of use, use ratio, magnitude ratio, and the bilateral magnitude. Density plots can be constructed that visually represent the data from the 24 h wearing period. The variables and their resultant density plots are highly consistent in neurologically-intact, community-dwelling adults. This striking consistency makes them a useful tool for determining if upper limb daily performance is different from normal. This methodology is appropriate for research studies investigating upper limb dysfunction and interventions designed to improve upper limb performance in daily life in people with stroke and other patient populations. Because of its relative simplicity, it may not be long before it is also incorporated in clinical neurorehabilitation practice.

This protocol describes a method to quantify upper limb performance in daily life using wrist-worn accelerometers.

Un metodo per la quantificazione degli arti superiori performance nella vita quotidiana che utilizzano accelerometri

A key reason for referral to rehabilitation services after stroke and other neurological conditions is to improve one's ability to function in daily life. ...

An In Vitro Approach to Photodynamic Therapy

Photodynamic therapy (PDT) is a medical procedure that involves incubation of an exogenously applied photosensitizer (PS) followed by visible light photoactivation to induce cell apoptosis. The Federal Drug Administration has approved PDT for the treatment of actinic keratosis, and clinical guidelines recommend PDT as a treatment for certain non-melanoma skin cancers and acne vulgaris. PDT is an advantageous therapeutic modality as it is low cost, non-invasive, and associated with minimal adverse events and scaring. In the first step of PDT, a PS is applied and allowed to accumulate intracellularly. Subsequent light irradiation induces reactive oxygen species formation, which may ultimately lead to cell apoptosis, membrane disruption, mitochondrial damage, immune modulation, keratinocyte proliferation, and collagen turnover. Herein, we present an in vitro method to study PDT in an adherent cell line. This treatment protocol is designed to simulate PDT and may be adjusted to studying the use of PDT with various cell lines, photosensitizers, incubation temperatures, or photoactivation wavelengths. Squamous cell carcinoma cells were incubated with 0, 0.5, 1.0, and 2 mM 5-aminolevulinic acid (5-ALA) for 30 min and photoactivated with 417 nm blue light for 1,000 s. The primary outcome measure was apoptosis and necrosis, as measured by annexin-V and 7-aminoactinomycin D flow cytometry. There was a dose-dependent increase in cell apoptosis following thirty-minute incubation of 5-ALA. To achieve high inter-test validity, it is important to maintain consistent incubation and light parameters when performing in vitro PDT experiments. PDT is a useful clinical procedure and in vitro research may allow for the development of novel PSs, optimization of protocols, and new indications for PDT.

An In Vitro Approach to Photodynamic Therapy

Photodynamic therapy (PDT) is a medical procedure that involves incubation of an exogenously applied photosensitizer (PS) followed by visible light photoactivation to induce apoptosis. We present an in vitro PDT protocol designed to simulate PDT that may be used to study differences in PS incubation and light treatment parameters.

Un approccio In Vitro alla terapia fotodinamica

Photodynamic therapy (PDT) is a medical procedure that involves incubation of an exogenously applied photosensitizer (PS) followed by visible light ...

Preparation Of Gushukang (GSK) Granules for In Vivo and In Vitro Experiments

Traditional Chinese herbal medicine plays a role as an alternative method in treating many diseases, such as postmenopausal osteoporosis (POP). Gushukang (GSK) granules, a marketed prescription in China, have bone-protective effects in treating POP. Before administration to the body, one standard preparation procedure is commonly required, which aims to promote the release of active constituents from raw herbs and enhance the pharmacological effects as well as therapeutic outcomes. This study proposes a detailed protocol for using GSK granules in in vivo and in vitro experimental assays. The authors first provide a detailed protocol to calculate the animal-appropriate dosages of granules for in vivo investigation: weighing, dissolving, storage, and administration. Second, this article describes protocols for micro-CT scanning and the measurement of bone parameters. Sample preparation, protocols for running the micro-CT machine and quantification of bone parameters were evaluated. Third, serum-containing GSK granules are prepared, and drug-containing serum is extracted for in vitro osteoclastogenesis and osteoblastogenesis. GSK granules were intragastrically administered twice per day to rats for three consecutive days. Blood was then collected, centrifuged, inactivated, and filtered. Finally, serum was diluted and used for performing osteoclastogenesis and osteoblastogenesis. The protocol described here can be considered a reference for pharmacological investigations of herbal prescription medicines, such as granules.

Preparation Of Gushukang GSK Granules for In Vivo and In Vitro Experiments

This article provides a detailed protocol for preparing a working solution of Gushukang granules for animal studies and GSK granule containing serum for in vitro experiments. This protocol can be applied to pharmacological investigations of herbal medicines as well as prescriptions for both in vivo and in vitro experiments.

Preparazione di Gushukang (GSK) Granuli per in vivo e in vitro

Traditional Chinese herbal medicine plays a role as an alternative method in treating many diseases, such as postmenopausal osteoporosis (POP). Gushukang ...

Large Animal Model for Evaluating the Efficacy of the Gene Therapy in Ischemic Heart

Coronary artery disease is one of the significant causes of mortality and morbidity worldwide. Despite the progression of current therapeutics, a considerable proportion of coronary artery disease patients remain symptomatic. Gene therapy-mediated therapeutic angiogenesis offers a novel therapeutic method for improving myocardial perfusion and relieving symptoms. Gene therapy with different angiogenic factors has been studied in few clinical trials. Due to the novelty of the method, the progress of myocardial gene therapy is a continuous path from bench to bedside. Therefore, large animal models are needed for evaluating the safety and efficacy. The more the large animal model identifies the original disease and the endpoints used in clinics, the more predictable outcomes are from clinical trials. Here, we introduce a large animal model for evaluating the efficacy of the gene therapy in the ischemic porcine heart. We use clinically relevant imaging methods such as ultrasound imaging and 15H2O-PET. For targeting the gene transfers into the desired area, electroanatomical mapping is used. The aim of this method is: (1) to mimic chronic coronary artery disease, (2) to induce therapeutic angiogenesis at hypoxic areas of the heart, and (3) to evaluate the safety and efficacy of the gene therapy by using relevant endpoints.

Myocardial gene therapy for ischemic heart disease holds great promise for future therapeutics. Here, we introduce a large animal model for evaluating the efficacy of gene therapy in the ischemic heart.