title: Bioassay-Guided Isolation of Two Flavonoids from Derris scandens with Topoisomerase II Poison Activity.
abstract: Derris scandens (ROXB.) BENTH. (Fabaceae) is used as an alternative treatment for cancer in Thai traditional medicine. Investigation of the topoisomerase II (Top2) poison of compounds isolated from this plant may reveal new drug leads for the treatment of cancer. Bioassay-guided isolation was performed on an extract of D. scandens stems using a yeast cell-based assay. A yeast strain expressing the top2-1 temperature-sensitive mutant was used to assay Top2 activity. At the permissive temperature of 25°C, yeast cells were highly sensitive to Top2 poison agents. At the semi-permissive temperature of 30°C, where enzyme activity was present but greatly diminished, cells displayed only marginal sensitivity. The bioassay-guided fractionation of the extract led to the isolation of two known isoflavones: 5,7,4'-trihydroxy-6,8-diprenylisoflavone (1) and lupalbigenin (2). These two compounds also displayed cytotoxicity against three different cancer cell lines, KB, MCF-7 and NCI-H187. In conclusion, Top2 poison agents from D. scandens are reported for the first time, substantiating the use of D. scandens in Thai traditional medicine for cancer treatment.
authors.affiliation: Department of Pharmacognosy and Pharmaceutical Botany, Unit Cell for Research and Development of Herbal Medicines, Biomaterials and Dental Material for Dental Care and Therapy.
authors.forename: Suphattra
authors.initials: S
authors.lastname: Sangmalee
authors.forename: Areerat
authors.initials: A
authors.lastname: Laorpaksa
authors.forename: Boonchoo
authors.initials: B
authors.lastname: Sritularak
authors.forename: Suchada
authors.initials: S
authors.lastname: Sukrong
mesh_terms: D000818:Animals; D000970:Antineoplastic Agents / Q000302:isolation & purification / Q000633:toxicity; D001681:Biological Assay; D045744:Cell Line, Tumor; D002470:Cell Survival / Q000187:drug effects; D002522:Chlorocebus aethiops; D004250:DNA Topoisomerases, Type II / Q000235:genetics / Q000378:metabolism; D029866:Derris; D006801:Humans; D007529:Isoflavones / Q000302:isolation & purification / Q000633:toxicity; D018547:Plant Stems; D012441:Saccharomyces cerevisiae / Q000235:genetics; D059005:Topoisomerase II Inhibitors / Q000302:isolation & purification / Q000633:toxicity; D014709:Vero Cells
chemical_list: D000970:Antineoplastic Agents; D007529:Isoflavones; D059005:Topoisomerase II Inhibitors; D004250:DNA Topoisomerases, Type II