BMC Cancer Research article Cytotoxic effects of Gemcitabine-loaded liposomes in human anaplastic thyroid carcinoma cells Marilena Celano1, Maria Grazia Calvagno1, Stefania Bulotta1, Donatella Paolino1,2, Franco Arturi1, Domenicoantonio Rotiroti1, Sebastiano Filetti3, Massimo Fresta1 and Diego Russo*1 BioMed Central Open Access Address: 1Department of Pharmacobiological Sciences, University of Catanzaro "Magna Græcia", 88100 Catanzaro, Italy, 2Department of Pharmaceutical Sciences, University of Catania, 95100 Catania, Italy and 3Department of Clinical Sciences, University of Roma "La Sapienza", 00100 Roma, Italy Email: Marilena Celano - celano.donato@tiscali.it; Maria Grazia Calvagno - marycalv@yahoo.com; Stefania Bulotta - bulotta@unicz.it; Donatella Paolino - paolino@unicz.it; Franco Arturi - arturi@unicz.it; Domenicoantonio Rotiroti - rotiroti@unicz.it; Sebastiano Filetti - sebastiano.filetti@uniroma1.it; Massimo Fresta - fresta@unicz.it; Diego Russo* - d.russo@unicz.it * Corresponding author Published: 13 September 2004 BMC Cancer 2004, 4:63 doi:10.1186/1471-2407-4-63 This article is available from: http://www.biomedcentral.com/1471-2407/4/63 Received: 02 March 2004 Accepted: 13 September 2004 © 2004 Celano et al; licensee BioMed Central Ltd. This is an open-access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Abstract Background: Identification of effective systemic antineoplastic drugs against anaplastic thyroid carcinomas has particularly important implications. In fact, the efficacy of the chemotherapeutic agents presently used in these tumours, is strongly limited by their low therapeutic index. Methods: In this study gemcitabine was entrapped within a pegylated liposomal delivery system to improve the drug antitumoral activity, thus exploiting the possibility to reduce doses to be administered in cancer therapy. The cytotoxic effects of free or liposome-entrapped gemcitabine was evaluated against a human thyroid tumour cell line. ARO cells, derived from a thyroid anaplastic carcinoma, were exposed to different concentrations of the drug. Liposomes formulations were made up of 1,2-dipalmitoyl-sn-glycero-3-phosphocholine/cholesterol/1,2- distearoyl-sn-glycero-3-phosphoethanolamine-MPEG (8:3:1 molar ratio). Cell viability was assessed by both trypan bleu dye exclusion assay and fluorimetric analysis of cell DNA content. Results: A cytotoxic effect of free gemcitabine was present only after 72 h incubation (ARO cell mortality increased of approximately 4 fold over control at 1 µM, 7 fold at 100 µM). When gemcitabine was encapsulated in liposomes, a significant effect was observed by using lower concentrations of the drug (increased cell mortality of 2.4 fold vs. control at 0.3 µM) and earlier exposure time (24 h). Conclusion: These findings show that, in vitro against human thyroid cancer cells, the gemcitabine incorporation within liposomes enhances the drug cytotoxic effect with respect to free gemcitabine, thus suggesting a more effective drug uptake inside the cells. This may allow the use of new formulations with lower dosages (side effect free) for the treatment of anaplastic human thyroid tumours. Page 1 of 5 (page number not for citation purposes)