title: Antitumor activity of palmitic acid found as a selective cytotoxic substance in a marine red alga.
abstract: In a previous report, we discussed an extract from a marine red alga, Amphiroa zonata, which shows selective cytotoxic activity to human leukemic cells, but no cytotoxicity to normal human dermal fibroblast (HDF) cells in vitro. In this study, we identified palmitic acid, a selective cytotoxic substance from the marine algal extract, and investigated its biological activities. At concentrations ranging from 12.5 to 50 micrograms/ml, palmitic acid shows selective cytotoxicity to human leukemic cells, but no cytotoxicity to normal HDF cells. Furthermore, palmitic acid induces apoptosis in the human leukemic cell line MOLT-4 at 50 micrograms/ml. Palmitic acid also shows in vivo antitumor activity in mice. One molecular target of palmitic acid in tumor cells is DNA topoisomerase I, however, interestingly, it does not affect DNA topoisomerase II, suggesting that palmitic acid may be a lead compound of anticancer drugs.
authors.affiliation: Marine and Highland Bioscience Center, Saga University, 152-1 Shonan-cho, Karatsu, Saga 847-0021, Japan.
authors.forename: Hideki
authors.initials: H
authors.lastname: Harada
authors.forename: Uki
authors.initials: U
authors.lastname: Yamashita
authors.forename: Hideyuki
authors.initials: H
authors.lastname: Kurihara
authors.forename: Eri
authors.initials: E
authors.lastname: Fukushi
authors.forename: Jun
authors.initials: J
authors.lastname: Kawabata
authors.forename: Yuto
authors.initials: Y
authors.lastname: Kamei
mesh_terms: D000818:Animals; D000970:Antineoplastic Agents / Q000737:chemistry* / Q000302:isolation & purification / Q000494:pharmacology*; D002455:Cell Division / Q000187:drug effects; D004354:Drug Screening Assays, Antitumor; D004791:Enzyme Inhibitors / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology; D018922:HL-60 Cells / Q000187:drug effects; D006801:Humans; D020014:K562 Cells / Q000187:drug effects; D007938:Leukemia / Q000188:drug therapy / Q000473:pathology; D051379:Mice; D008809:Mice, Inbred C3H; D019308:Palmitic Acid / Q000737:chemistry* / Q000302:isolation & purification / Q000494:pharmacology*; D000461:Rhodophyta / Q000737:chemistry*; D059004:Topoisomerase I Inhibitors; D059005:Topoisomerase II Inhibitors
chemical_list: D000970:Antineoplastic Agents; D004791:Enzyme Inhibitors; D059004:Topoisomerase I Inhibitors; D059005:Topoisomerase II Inhibitors; D019308:Palmitic Acid