Antitumor-promoting activity of coumarins from citrus plants.
In order to identify antitumor-promoting agents, we performed primary in vitro screening of 31 coumarins isolated from 11 plants of the Citrus species (Rutaceae), examining their possible inhibitory effects on Epstein-Barr virus early antigen (EBV-EA) activation induced by 12- O-tetradecanoylphorbol-13-acetate (TPA) in Raji cells. Some of the 8-substituted coumarins, 8-formyl-7-hydroxycoumarin (5), osthenol (7), demethylauraptenol (8), osthenon (9) and dihydroosthenon (10), were found to significantly inhibit EBV-EA activation (IC50: 129-207 mol ratio/32 pmol TPA). Osthenol (7) exhibited a marked inhibitory effect on mouse skin tumor promotion in an in vivo two-stage carcinogenesis test.
Ito
Chihiro
C
Faculty of Pharmacy, Meijo University, Tempaku, Nagoya, Japan.
Itoigawa
Masataka
M
Ju-ichi
Motoharu
M
Sakamoto
Naoyuki
N
Tokuda
Harukuni
H
Nishino
Hoyoku
H
Furukawa
Hiroshi
H
D015127:9,10-Dimethyl-1,2-benzanthracene; D000818:Animals; D000972:Antineoplastic Agents, Phytogenic / Q000008:administration & dosage / Q000494:pharmacology* / Q000627:therapeutic use; D045744:Cell Line, Tumor / Q000187:drug effects; D002957:Citrus; D003374:Coumarins / Q000008:administration & dosage / Q000494:pharmacology / Q000627:therapeutic use; D020128:Inhibitory Concentration 50; D051379:Mice; D008517:Phytotherapy; D012878:Skin Neoplasms / Q000139:chemically induced / Q000188:drug therapy / Q000473:pathology
D000972:Antineoplastic Agents, Phytogenic; D003374:Coumarins; D015127:9,10-Dimethyl-1,2-benzanthracene