title: Enhanced photodynamic antitumor effect on gastric cancer by a novel photosensitive stealth liposome.
abstract: Lipophilic photosensitizers hold potential for cancer photodynamic therapy. We sought to develop a novel photosensitive stealth liposome (PSSL) which incorporating a lipophilic photosensitizer into its lipid bilayer and to examine its photoactivity. We prepared PSSL composed of lipophilic chlorin e6 (Ce6) ester, dilauroylphosphatidylcholine, dioleoylphosphatidylethanolamine and distearoyl-phosphoethanolamine-N-[poly (ethylene glycol) 2000] and evaluated its photodynamic effect against gastric cancer cell lines and tumor-bearing nude mice models. In gastric cancer cell lines, LC(80) of PSSL was a maximum of 53 times as low as that of Ce6 sodium salt (Ce6-Na). PSSL completely destroyed all tumors in animal models and tumor recurrence levels were minimal (1.5 +/- 0.9%). PSSL achieved greater photodynamic effects in gastric cancer cell lines and in murine models than Ce6-Na. PSSL holds promise for photodynamic therapy for gastric cancer.
authors.affiliation: Institute of Clinical Medicine and Research, The Jikei University School of Medicine, 163-1 Kashiwa-shita, Kashiwa City, Chiba 277-8567, Japan. yoshihisan@jikei.ac.jp
authors.forename: Yoshihisa
authors.initials: Y
authors.lastname: Namiki
authors.forename: Tamami
authors.initials: T
authors.lastname: Namiki
authors.forename: Masataka
authors.initials: M
authors.lastname: Date
authors.forename: Kazuyoshi
authors.initials: K
authors.lastname: Yanagihara
authors.forename: Masakazu
authors.initials: M
authors.lastname: Yashiro
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Takahashi
mesh_terms: D000818:Animals; D045744:Cell Line, Tumor; D004337:Drug Carriers; D007834:Lasers; D008051:Lipid Bilayers; D008081:Liposomes; D051379:Mice; D008819:Mice, Nude; D008856:Microscopy, Fluorescence; D009368:Neoplasm Transplantation; D010778:Photochemotherapy; D017319:Photosensitizing Agents / Q000008:administration & dosage* / Q000493:pharmacokinetics / Q000627:therapeutic use*; D013056:Spectrophotometry, Ultraviolet; D013274:Stomach Neoplasms / Q000473:pathology / Q000628:therapy*; D014018:Tissue Distribution
chemical_list: D004337:Drug Carriers; D008051:Lipid Bilayers; D008081:Liposomes; D017319:Photosensitizing Agents