title: Liposomal delivery enhances short-chain ceramide-induced apoptosis of breast cancer cells.
abstract: It is therapeutically desirable to effectively deliver ceramide, an antimitogenic and proapoptotic lipid second messenger, to transformed cell types. However, the targeted delivery of cell-permeable ceramide analogs, including C6-ceramide, to cells may be impeded by the hydrophobicity of these bioactive lipids, resulting in reduced efficacy. The objective of this study is to develop and optimize liposomal vehicles to augment ceramide delivery to a breast adenocarcinoma cell line. We designed conventional, cationic, and pegylated drug release vesicles to efficaciously deliver ceramide to MDA-MB-231 breast adenocarcinoma cells. In vitro pharmacokinetic analysis demonstrated that liposomal ceramide delivery resulted in significantly greater accumulation of ceramide in MDA-MB-231 cells. Ceramide-formulated liposomes significantly inhibited MDA-MB-231 cell proliferation as compared with nonliposomal administration of ceramide. Ceramide-induced apoptosis correlated with the pharmacokinetic profile and the diminished proliferation in this highly aggressive, metastatic cell line. Liposomal ceramide formulations inhibited phosphorylated Akt levels and stimulated caspase-3/7 activity more effectively than nonliposomal ceramide, events consistent with apoptosis. Together, these results indicate that bioactive ceramide analogs can be incorporated into conventional, cationic, or pegylated liposomal vehicles for improved drug delivery and release.
authors.affiliation: Department of Pharmacology, Penn State College of Medicine, P.O. Box 850, Hershey, PA 17033, USA.
authors.forename: Tom
authors.initials: T
authors.lastname: Stover
authors.forename: Mark
authors.initials: M
authors.lastname: Kester
mesh_terms: D017209:Apoptosis; D001943:Breast Neoplasms / Q000473:pathology; D002455:Cell Division / Q000187:drug effects; D002518:Ceramides / Q000008:administration & dosage* / Q000493:pharmacokinetics; D002626:Chemistry, Pharmaceutical; D004337:Drug Carriers; D016503:Drug Delivery Systems; D005260:Female; D006801:Humans; D008081:Liposomes / Q000737:chemistry*; D015398:Signal Transduction / Q000502:physiology; D014407:Tumor Cells, Cultured
chemical_list: D002518:Ceramides; D004337:Drug Carriers; D008081:Liposomes; C101954:N-caproylsphingosine