Development of a liposome-encapsulated radionuclide with preferential tumor accumulation--the choice of radionuclide and chelating ligand.
Various radionuclide-ligand complexes were encapsulated in liposomes and their accumulations in tumors were studied. Increased tumor accumulation was observed with every complex in the liposome-encapsulated form. However, different accumulation levels were registered for the various radionuclides even though they were all delivered using a similar liposome formulation. Though the liposomes remained intact in the circulation, they were degraded in the tumor, liver and spleen eventually. Thus, this suggests that tumor accumulation of liposome-encapsulated radionuclides is dependent on not only the in vivo behavior of the liposomes themselves, but also the characteristics of nuclide-ligand complexes after their release from liposomes. A correct choice of radionuclides and ligands for encapsulation in liposomes would enable excellent tumor-imaging agents to be achieved.
Ogihara-Umeda
I
I
Faculty of Pharmaceutical Sciences, Teikyo University, Kanagawa, Japan.
Sasaki
T
T
Nishigori
H
H
D000818:Animals; D002614:Chelating Agents; D002784:Cholesterol; D002860:Chromium Radioisotopes / Q000008:administration & dosage / Q000493:pharmacokinetics*; D003037:Cobalt Radioisotopes / Q000008:administration & dosage / Q000493:pharmacokinetics*; D004337:Drug Carriers; D005710:Gallium Radioisotopes / Q000008:administration & dosage / Q000493:pharmacokinetics*; D007504:Iron Radioisotopes / Q000008:administration & dosage / Q000493:pharmacokinetics*; D008024:Ligands; D008081:Liposomes; D008297:Male; D051379:Mice; D008815:Mice, Inbred Strains; D010713:Phosphatidylcholines; D012510:Sarcoma 180 / Q000378:metabolism*; D013997:Time Factors; D014018:Tissue Distribution
D002614:Chelating Agents; D002860:Chromium Radioisotopes; D003037:Cobalt Radioisotopes; D004337:Drug Carriers; D005710:Gallium Radioisotopes; D007504:Iron Radioisotopes; D008024:Ligands; D008081:Liposomes; D010713:Phosphatidylcholines; D002784:Cholesterol; C010942:1,2-distearoyllecithin