Increased efficacy of aphidicolin killing of human neuroblastoma cells in vitro by encapsulation in liposomes

Aphidicolin is a tetracyclic diterpene antibiotic which kills human neuroblastoma cells (NB) in vitro while it has no significant effect on the viability of different human cell types including normal embryonal cells. In the present study, we tested whether aphidicolin encapsulated in liposomes kills NB cells with the efficacy superior to that of unencapsulated aphidicolin. The drug was entrapped in vesicles composed of phosphatidylcholine, phosphatidylserine and cholesterol in a molar ratio of 83 : 5 : 12. The treatment with encapsulated aphidicolin at a concentration of 200 nmol for 5 days killed all cells of three human NB cell lines. In contrast, at least 30% of the cells survived 5 days of treatment with 200 nmol unencapsulated aphidicolin The results showed that aphidicolin killing of human NB cells may be increased by encapsulation in liposomes.