title: Constituents of Brazilian red propolis and their preferential cytotoxic activity against human pancreatic PANC-1 cancer cell line in nutrient-deprived condition.
abstract: Human pancreatic cancer cells such as PANC-1 are known to exhibit marked tolerance to nutrition starvation that enables them to survive for prolonged period of time even under extremely nutrient-deprived conditions. Thus, elimination of this tolerance to nutrition starvation is regarded as a novel approach in anticancer drug development. In this study, the MeOH soluble extract of Brazilian red propolis was found to kill 100% PANC-1 cells preferentially in the nutrient-deprived condition at the concentration of 10 microg/mL. Further phytochemical investigation led to the isolation of 43 compounds including three new compounds, (6aS,11aS)-6a-ethoxymedicarpan (1), 2-(2',4'-dihydroxyphenyl)-3-methyl-6-methoxybenzofuran (2), and 2,6-dihydroxy-2-[(4-hydroxyphenyl)methyl]-3-benzofuranone (3). Among them, (6aR,11aR)-3,8-dihydroxy-9-methoxypterocarpan (21, DMPC) displayed the most potent 100% preferential cytotoxicity (PC(100)) at the concentration of 12.5 microM. Further study on the mode of cell death induced by DMPC against PANC-1 cells indicated that killing process was not accompanied by DNA fragmentation, rather through a nonapoptotic pathway accompanied by necrotic-type morphological changes.
authors.affiliation: Institute of Natural Medicine, University of Toyama, 2630 Sugitani, Toyama 930-0194, Japan.
authors.forename: Suresh
authors.initials: S
authors.lastname: Awale
authors.forename: Feng
authors.initials: F
authors.lastname: Li
authors.forename: Hiroko
authors.initials: H
authors.lastname: Onozuka
authors.forename: Hiroyasu
authors.initials: H
authors.lastname: Esumi
authors.forename: Yasuhiro
authors.initials: Y
authors.lastname: Tezuka
authors.forename: Shigetoshi
authors.initials: S
authors.lastname: Kadota
mesh_terms: D000970:Antineoplastic Agents / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology; D045744:Cell Line, Tumor; D004354:Drug Screening Assays, Antitumor; D006801:Humans; D009336:Necrosis / Q000139:chemically induced; D009751:Nutritional Requirements; D010190:Pancreatic Neoplasms / Q000188:drug therapy* / Q000473:pathology*; D008517:Phytotherapy; D010936:Plant Extracts / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology; D011429:Propolis / Q000737:chemistry* / Q000627:therapeutic use*; D012680:Sensitivity and Specificity
chemical_list: D000970:Antineoplastic Agents; D010936:Plant Extracts; D011429:Propolis