title: Preferential action of liposome-entrapped 1-(2-chloroethyl)-3-(4-methylcyclohexyl)-1-nitrosourea on lung metastasis of Lewis lung carcinoma as compared with the free drug.
abstract: Lipid vesicles entrapping a lipophilic antitumor agent, 1-(2-chloroethyl)-3-(4-methylcyclohexyl)-1-nitrosourea (MeCCNU), within the membrane phase were prepared and their antimetastatic activity was compared with that of free MeCCNU using intravenously inoculated Lewis lung carcinoma. It was found that the liposome preparation exhibited more potent inhibitory activity than the free drug on colony formation in the lung, when administered intravenously as well as intraperitoneally. Superior life-prolongation effect was also observed with liposome preparations as compared with the free drug in this system. However, the two forms of MeCCNU showed almost the same activity against not only Lewis lung carcinoma but also P388 leukemia inoculated subcutaneously and intraperitoneally, respectively. These results suggest that the superior effect of liposome-entrapped MeCCNU on lung metastasis might be due, at least in part, to preferential distribution of liposomes to the lung as compared with the free drug.
mesh_terms: D000818:Animals; D008081:Liposomes / Q000008:administration & dosage*; D008175:Lung Neoplasms / Q000188:drug therapy* / Q000556:secondary; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D008811:Mice, Inbred DBA; D009374:Neoplasms, Experimental / Q000188:drug therapy; D009607:Nitrosourea Compounds / Q000627:therapeutic use*; D012673:Semustine / Q000008:administration & dosage / Q000627:therapeutic use*
chemical_list: D008081:Liposomes; D009607:Nitrosourea Compounds; D012673:Semustine