title: Chemopreventive effects of polysaccharides extract from Asterina pectinifera on HT-29 human colon adenocarcinoma cells.
abstract: We examined the effects of polysaccharides extracted from Asterina pectinifera on the activities of quinone reductase (QR), glutathione S-transferase (GST), ornithine decarboxylase (ODC), cyclooxygenase (COX)-2 and glutathione (GSH) levels in HT-29 human colon adenocarcinoma cells. We found that the polysaccharides extract induced QR activity in a dose-dependent manner over a concentration range of 20 approximately 60 microg/ml and increased GST activity as much as 1.4-fold over controls. GSH levels were increased 1.3- and 1.5-fold with the extract at 40 and 60 microg/ml, respectively. The activity and protein expression of ODC in 12-O-tetradecanoylphorbol-13-acetate (TPA)-induced colon cancer cells was inhibited by the extract. The polysaccharides suppressed TPA-induced prostaglandin (PG) production. These data indicate that polysaccharides from A. pectinifera increase phase II detoxification enzyme activity and inhibit ODC and COX-2 activities in HT-29 human colon adenocarcinoma cells. Consequently, this effect may contribute to the protective effect of polysaccharides from A. pectinifera against colon cancer.
authors.affiliation: Department of Pharmacology, College of Medicine, Dongguk University, Gyeongju 780-714, Korea.
authors.forename: Kyung-Soo
authors.initials: KS
authors.lastname: Nam
authors.forename: Yun-Hee
authors.initials: YH
authors.lastname: Shon
mesh_terms: D000230:Adenocarcinoma / Q000201:enzymology*; D000818:Animals; D047288:Asterina / Q000737:chemistry*; D003110:Colonic Neoplasms / Q000201:enzymology*; D051546:Cyclooxygenase 2 / Q000378:metabolism; D016861:Cyclooxygenase Inhibitors / Q000378:metabolism; D004305:Dose-Response Relationship, Drug; D005978:Glutathione / Q000378:metabolism; D005982:Glutathione Transferase / Q000378:metabolism; D019073:HT29 Cells / Q000187:drug effects*; D006801:Humans; D016660:NAD(P)H Dehydrogenase (Quinone) / Q000378:metabolism; D009955:Ornithine Decarboxylase / Q000378:metabolism; D065108:Ornithine Decarboxylase Inhibitors; D011134:Polysaccharides / Q000494:pharmacology*
chemical_list: D016861:Cyclooxygenase Inhibitors; D065108:Ornithine Decarboxylase Inhibitors; D011134:Polysaccharides; D051546:Cyclooxygenase 2; C496540:PTGS2 protein, human; D016660:NAD(P)H Dehydrogenase (Quinone); D005982:Glutathione Transferase; D009955:Ornithine Decarboxylase; D005978:Glutathione