Cytotoxic effects of compounds from Iris tectorum on human cancer cell lines.
In the course of searching for novel cytotoxic compounds which can be used in chemotherapy, several Traditional Chinese Medicines (TCM) have been screened by bioassay-guided fractionation and isolation. An extract of rhizomes of Iris tectorum Maxim., a TCM used to treat cancer, exhibited highest potency and led to the isolation of two flavonoids, 7-O-methylaromadendrin and tectorigenin, and four iridal-type triterpenes, iritectols A and B, isoiridogermanal and iridobelamal A. The cytotoxicities of the isolated compounds against four human cancer cell lines were evaluated by the SRB assay. Iritectol B, isoiridogermanal and iridobelamal A showed similar cytotoxicity with IG(50) around 11 microM and 23 microM against MCF-7 and C32 cell lines, respectively. Cell cycle-specific inhibition and apoptosis induced by the isolated compounds were determined using flow cytometry with two sets of co-labelling systems: annexin V-FITC/propidium iodide and fluorescein diacetate/propidium iodide. Iritectol B demonstrated dose-dependent apoptotic effect against COR-L23 cells with an apoptotic rate of 33% at 100 microM. Tectorigenin (an analogue of genistein) showed cell cycle specific inhibition and arrested cells at G(2)/M phase up to 400 microM, but did not demonstrate apoptotic effect against COR-L23 cells up to 1 mM. The overall activities of isolated compounds observed in the present study support the traditional use of Iris tectorum Maxim. in the treatment of cancer.
Fang
Rui
R
Centre for Natural Medicines Research, King's College London, Franklin-Wilkins Building, 150 Stamford Street, London SE1 9NH, United Kingdom.
Houghton
Peter J
PJ
Hylands
Peter J
PJ
D000972:Antineoplastic Agents, Phytogenic / Q000008:administration & dosage / Q000302:isolation & purification / Q000494:pharmacology*; D017209:Apoptosis / Q000187:drug effects; D002453:Cell Cycle / Q000187:drug effects; D045744:Cell Line, Tumor; D004305:Dose-Response Relationship, Drug; D004365:Drugs, Chinese Herbal / Q000494:pharmacology; D005419:Flavonoids / Q000008:administration & dosage / Q000302:isolation & purification / Q000494:pharmacology; D005434:Flow Cytometry; D006801:Humans; D031323:Iris Plant / Q000737:chemistry*; D010936:Plant Extracts / Q000008:administration & dosage / Q000494:pharmacology*; D027343:Rhizome; D014315:Triterpenes / Q000008:administration & dosage / Q000302:isolation & purification / Q000494:pharmacology
D000972:Antineoplastic Agents, Phytogenic; D004365:Drugs, Chinese Herbal; D005419:Flavonoids; D010936:Plant Extracts; D014315:Triterpenes