Inhibitory Effect of Hybrid Liposomes on the Growth of NP2 Glioma Cells

Keiji Kuwabara, Hideaki Ichihara, Yoko Matsumoto

The inhibitory activity of hybrid liposomes (HLs), composed of 90 mol% L-α-dimyristoyl-phosphatidylcholine (DMPC) and 10 mol% polyoxyethylene (25) dodecyl ether (C12(EO)25), was investigated in human glioma NP2 cells. HLs with a hydrodynamic diameter below 100 nm persisted for 4 weeks. The inhibitory effect of HLs on the proliferation of NP2 cells was evaluated. Induction of apoptosis in NP2 cells treated with HL was measured through a PI assay and the TUNEL method. HLs caused apoptosis in NP2 cells through the mitochondrial pathway. An increase of AIF protein expression was observed in HL-treated cells. Cellular membrane fluidity of NP2 cells was also increased as revealed by the fluorescence depolarization method. Enhanced HL accumulation in the membrane of NP2 cells was observed.