title: Inhibitory effects of phaseolotoxin on proliferation of leukemia cells HL-60, K-562 and L1210 and pancreatic cells RIN-m5F.
abstract: Phaseolotoxin (PT) is a non-host specific phytotoxin produced by the plant pathogenic bacterium Pseudomonas syringae (P.s.) pv. phaseolicola. In the present study, the inhibitory effect of PT on the proliferation of leukemia cells was studied. After 4 days of treatment, PT decreased cell growth of leukemia cell lines HL-60, K-562 and L1210 in a dose-dependent manner. In addition, PT also reduced cell growth of the insulinoma pancreatic cell line RIN-m5F. IC50 values were 2.1 +/- 1.0 microM (HL-60), 13.3 +/- 3.7 microM (K-562), 2.5 +/- 0.4 microM (L1210) and 5.5 +/- 0.3 microM (RIN-m5F). Although the exact mechanism by which PT inhibits cell growth in these cells is currently not known, we present first evidence that PT may in part be active via inhibition of ornithine decarboxylase (ODC). Based on our findings, PT presents a lead compound with potential for further development into a new anti-cancer agent.
authors.affiliation: Pacific Biomedical Research Center and Biotechnology Program, University of Hawaii at Manoa, 1993 East-West Road, Honolulu, HI 96822, USA. abachmann@crch.hawaii.edu
authors.forename: André S
authors.initials: AS
authors.lastname: Bachmann
authors.forename: Ronghui
authors.initials: R
authors.lastname: Xu
authors.forename: Lal
authors.initials: L
authors.lastname: Ratnapala
authors.forename: Suresh S
authors.initials: SS
authors.lastname: Patil
mesh_terms: D000818:Animals; D000970:Antineoplastic Agents / Q000494:pharmacology*; D002455:Cell Division / Q000187:drug effects; D045744:Cell Line, Tumor / Q000187:drug effects; D004791:Enzyme Inhibitors / Q000494:pharmacology; D005098:Exotoxins / Q000494:pharmacology*; D005260:Female; D018922:HL-60 Cells / Q000187:drug effects; D006801:Humans; D007340:Insulinoma / Q000473:pathology; D020014:K562 Cells / Q000187:drug effects; D007939:Leukemia L1210 / Q000473:pathology; D051379:Mice; D009952:Ornithine / Q000031:analogs & derivatives; D065108:Ornithine Decarboxylase Inhibitors; D010190:Pancreatic Neoplasms / Q000473:pathology; D051381:Rats
chemical_list: D000970:Antineoplastic Agents; D004791:Enzyme Inhibitors; D005098:Exotoxins; D065108:Ornithine Decarboxylase Inhibitors; C021234:phaseolotoxin; D009952:Ornithine