Therapeutic Effects of Hybrid Liposomes Against Xenograft Mouse Model of Colorectal Cancer In Vivo Due to Long-term Accumulation.

Abstract

To examine therapeutic effects of hybrid liposomes (HL) composed of L-α-dimyristylphosphatidylcholine (DMPC) and polyoxyethylene (25) dodecyl ether (C12(EO)25) against human colorectal cancer (WiDr) cells in vitro and in vivo. HL composed of 90 mol% DMPC and 10 mol% C12(EO)25 were prepared by the sonication method. Therapeutic effects of HL in the subcutaneous xenograft model mice of colorectal cancer were examined in vivo. Inhibitory effects of HL on the growth of WiDr cells were obtained along with apoptosis measurement. Selective accumulation of HL, including a fluorescence probe (indocyanine green; (ICG)), was observed for WiDr cells using a fluorescence microscope. Remarkable reduction of tumor volume in xenograft model of mice topically HL-treated without drugs after the subcutaneous inoculation of WiDr cells was verified in vivo. Induction of apoptosis in tumor cells of xenograft mice topically administered with HL was observed in micrographs on the basis of terminal deoxynucleotidyl tranferase-mediated dUTP-biotin nick end labeling (TUNEL) method. Accumulation of HL, including ICG, for long-term into the tumor was obtained in the xenograft model. Therapeutic effects of HL without any drugs in the murine xenograft model after subcutaneous inoculation of human colorectal cancer were revealed for the first time in vivo due to long-term accumulation.