title: Mito-DCA: a mitochondria targeted molecular scaffold for efficacious delivery of metabolic modulator dichloroacetate.
abstract: Tumor growth is fueled by the use of glycolysis, which normal cells use only in the scarcity of oxygen. Glycolysis makes tumor cells resistant to normal death processes. Targeting this unique tumor metabolism can provide an alternative strategy to selectively destroy the tumor, leaving normal tissue unharmed. The orphan drug dichloroacetate (DCA) is a mitochondrial kinase inhibitor that has the ability to show such characteristics. However, its molecular form shows poor uptake and bioavailability and limited ability to reach its target mitochondria. Here, we describe a targeted molecular scaffold for construction of a multiple DCA loaded compound, Mito-DCA, with three orders of magnitude enhanced potency and cancer cell specificity compared to DCA. Incorporation of a lipophilic triphenylphosphonium cation through a biodegradable linker in Mito-DCA allowed for mitochondria targeting. Mito-DCA did not show any significant metabolic effects toward normal cells but tumor cells with dysfunctional mitochondria were affected by Mito-DCA, which caused a switch from glycolysis to glucose oxidation and subsequent cell death via apoptosis. Effective delivery of DCA to the mitochondria resulted in significant reduction in lactate levels and played important roles in modulating dendritic cell (DC) phenotype evidenced by secretion of interleukin-12 from DCs upon activation with tumor antigens from Mito-DCA treated cancer cells. Targeting mitochondrial metabolic inhibitors to the mitochondria could lead to induction of an efficient antitumor immune response, thus introducing the concept of combining glycolysis inhibition with immune system to destroy tumor.
authors.affiliation: NanoTherapeutics Research Laboratory, Department of Chemistry and ‡Department of Infectious Diseases, University of Georgia , Athens, Georgia 30602, United States.
authors.forename: Rakesh K
authors.initials: RK
authors.lastname: Pathak
authors.forename: Sean
authors.initials: S
authors.lastname: Marrache
authors.forename: Donald A
authors.initials: DA
authors.lastname: Harn
authors.forename: Shanta
authors.initials: S
authors.lastname: Dhar
mesh_terms: D000818:Animals; D000970:Antineoplastic Agents / Q000008:administration & dosage* / Q000494:pharmacology; D045744:Cell Line, Tumor; D003999:Dichloroacetic Acid / Q000008:administration & dosage* / Q000494:pharmacology; D004337:Drug Carriers / Q000737:chemistry*; D016503:Drug Delivery Systems; D005947:Glucose / Q000378:metabolism; D006801:Humans; D019344:Lactic Acid / Q000378:metabolism; D053078:Membrane Potential, Mitochondrial / Q000187:drug effects; D051379:Mice; D008810:Mice, Inbred C57BL; D008928:Mitochondria / Q000187:drug effects / Q000378:metabolism*; D009369:Neoplasms / Q000188:drug therapy / Q000378:metabolism; D009943:Organophosphorus Compounds / Q000737:chemistry; D047428:Protein Kinase Inhibitors / Q000008:administration & dosage* / Q000494:pharmacology
chemical_list: D000970:Antineoplastic Agents; D004337:Drug Carriers; D009943:Organophosphorus Compounds; D047428:Protein Kinase Inhibitors; D019344:Lactic Acid; D003999:Dichloroacetic Acid; D005947:Glucose