Stability and antitumor effects of all-trans retinoic acid-loaded liposomes contained sterylglucoside mixture.

The aim of this study was to develop an intravenous delivery of all-trans retinoic acid (ATRA) for the treatment of cancer. Two kinds of liposomes composed of dipalmitoylphosphatidylcholine and cholesterol with sterylglucoside (SG) mixture (SG liposomes) or without SG (non-SG liposomes) were prepared. A limited amount of ATRA was incorporated into liposomes approximately 3mol%. ATRA-loaded SG liposomes were more stable at 4 degrees C with light protection for 24 days than non-SG liposomes; maintaining 83.1% ATRA and the average diameter 198.5 nm (36 days), and in 80% rat serum for 120 min. SG seems to increase the ATRA-loaded efficiency in liposomes and stability of liposomes compared with cholesterol. The mean survival time of mice given SG liposomes (18.2 days) indicated a greater antitumor activity than saline (14.1 days) (P<0.001) without change of mean body weight. It is concluded that the current ATRA-loaded SG liposomes are potentially applicable for hepatic metastasis of M5076 tumor.