title: Synthesis and characterization of novel ceramide analogs for induction of apoptosis in human cancer cells.
abstract: A variety of anti-cancer drugs elevate endogenous ceramide, thereby inducing apoptosis in tumor cells. Recently, we have introduced novel ceramide analogs of the beta-hydroxy alkyl amide type, which trigger pro-apoptotic signaling pathways without prior elevation of endogenous ceramide. They induce apoptosis specifically in rapidly dividing neuroblastoma cells, but not in resting or differentiated cells. We characterize new ceramide mimics that have been derived from N-acylation of serinol (S), diethanolamine (B), propanolamine (P), and tris(hydroxy-methyl)methylamine (T) with myristic (14), palmitic (16), or oleic (18) acid. The water solubility of these compounds exceeds that of ceramide by more than 100-fold (up to 5 mM). Apoptosis of human neuroblastoma, glioma, medulloblastoma, and adenocarcinoma cells is induced by N-(2-hydroxy-1-(hydroxymethyl)ethyl)-palmitoylamide, C16-serinol (S16), N-(2-hydroxy-1-(hydroxymethyl)ethyl)-oleoylamide, C18-serinol (S18), N-bis(2-hydroxyethyl)-myristoyl-amide (B16), and N-tris(hydroxymethyl)methyl-oleoylamide (T18) within 60 min of incubation, and is completed even after removal of the compound from the medium. This is most likely due to a rapid uptake of the analogs followed by their slow release from the cells. Alteration of the acyl chain length to less than 14 methylene units, removal of the amino group, or reducing the number of hydroxyalkyl residues to less than two significantly lowers or eliminates the pro-apoptotic potential of these compounds. The target specificity of novel ceramide analogs for tumor cells, their water solubility, and fast pro-apoptotic mechanism indicates a high therapeutic potential for cancer treatment.
authors.affiliation: Institute of Molecular Medicine and Genetics, Medical College of Georgia, 1120 15th Street, Room CB-2803, Augusta, GA 30912, USA. ebieberich@mail.mcg.edu
authors.forename: Erhard
authors.initials: E
authors.lastname: Bieberich
authors.forename: Bin
authors.initials: B
authors.lastname: Hu
authors.forename: Jeane
authors.initials: J
authors.lastname: Silva
authors.forename: Sarah
authors.initials: S
authors.lastname: MacKinnon
authors.forename: Robert K
authors.initials: RK
authors.lastname: Yu
authors.forename: Helen
authors.initials: H
authors.lastname: Fillmore
authors.forename: William C
authors.initials: WC
authors.lastname: Broaddus
authors.forename: Raphael M
authors.initials: RM
authors.lastname: Ottenbrite
mesh_terms: D017209:Apoptosis; D002518:Ceramides / Q000138:chemical synthesis / Q000494:pharmacology*; D004305:Dose-Response Relationship, Drug; D006801:Humans; D016328:NF-kappa B / Q000378:metabolism; D009369:Neoplasms / Q000188:drug therapy / Q000473:pathology*; D013329:Structure-Activity Relationship; D014407:Tumor Cells, Cultured
chemical_list: D002518:Ceramides; D016328:NF-kappa B