Development of liposome for targeting therapy against brain tumor.

Liposomes were investigated as a carrier for the delivery of therapeutic agents to target brain tumors. We have developed the coating of liposomes with pullulan and 1-aminolactose pullulan, and compared with conventional neutral liposome. When pullulan-coated liposome labeled with¹⁴ C was intracarotidly administrated into the 9L cells immlanted brain tumor rats, brain tumor uptake of radioactivity increased 4.5 times and spleen uptake decrease compared with the neutral liposome. The cytotoxity of cisplatin against 9L-glioma cells was not inhibited by encapsulation of pullulan-coated liposmes. The quantity of platinum of 1-aminolactose pullulan-coated liposome-encapsulated cisplatin into the brain tumor was about 4 times as great as that of pullulan-coated liposome-encapsulated cisplatin. Considering that polysaccharide-coated liposomes become more stable, both physio chemically and biochemically, than conventional liposomes, 1-aminolactose pullulan-coated liposomes may be useful in targeting brain tumors.