title: CYP1-mediated antiproliferative activity of dietary flavonoids in MDA-MB-468 breast cancer cells.
abstract: Among the different mechanisms proposed to explain the cancer-protecting effect of dietary flavonoids, substrate-like interactions with cytochrome P450 CYP1 enzymes have recently been explored. In the present study, the metabolism of the flavonoids chrysin, baicalein, scutellarein, sinensetin and genkwanin by recombinant CYP1A1, CYP1B1 and CYP1A2 enzymes, as well as their antiproliferative activity in MDA-MB-468 human breast adenocarcinoma and MCF-10A normal breast cell lines, were investigated. Baicalein and 6-hydroxyluteolin were the only conversion products of chrysin and scutellarein metabolism by CYP1 family enzymes, respectively, while baicalein itself was not metabolized further. Sinensetin and genkwanin produced a greater number of metabolites and were shown to inhibit strongly in vitro proliferation of MDA-MB-468 cells at submicromolar and micromolar concentrations, respectively, without essentially affecting the viability of MCF-10A cells. Cotreatment of the CYP1 family inhibitor acacetin reversed the antiproliferative activity noticed for the two flavones in MDA-MB-468 cells to 13 and 14 microM respectively. In contrast chrysin, baicalein and scutellarein inhibited proliferation of MDA-MB-468 cells to a lesser extent than sinensetin and genkwanin. The metabolism of genkwanin to apigenin and of chrysin to baicalein was favored by CYP1B1 and CYP1A1, respectively. Taken together the data suggests that CYP1 family enzymes enhance the antiproliferative activity of dietary flavonoids in breast cancer cells, through bioconversion to more active products.
authors: Laboratory of Forensic Sciences and Toxicology, University of Crete, Heraklion, Voutes, Greece. vasilis_androutsopoulos@yahoo.com
authors: Vasilis P
authors: VP
authors: Androutsopoulos
authors: Ketan
authors: K
authors: Ruparelia
authors: Randolph R J
authors: RR
authors: Arroo
authors: Aristidis M
authors: AM
authors: Tsatsakis
authors: Demetrios A
authors: DA
authors: Spandidos
mesh_terms: D000230:Adenocarcinoma / Q000201:enzymology / Q000473:pathology*; D000970:Antineoplastic Agents / Q000378:metabolism / Q000494:pharmacology*; D001189:Aryl Hydrocarbon Hydroxylases / Q000037:antagonists & inhibitors / Q000378:metabolism*; D001711:Biotransformation; D001943:Breast Neoplasms / Q000201:enzymology / Q000473:pathology*; D045744:Cell Line, Tumor; D049109:Cell Proliferation / Q000187:drug effects*; D002470:Cell Survival / Q000187:drug effects; D019363:Cytochrome P-450 CYP1A1 / Q000378:metabolism; D019388:Cytochrome P-450 CYP1A2 / Q000378:metabolism; D065633:Cytochrome P-450 CYP1B1; D003640:Dealkylation; D004032:Diet; D004305:Dose-Response Relationship, Drug; D004791:Enzyme Inhibitors / Q000494:pharmacology; D005260:Female; D047309:Flavones / Q000494:pharmacology; D005419:Flavonoids / Q000378:metabolism / Q000494:pharmacology*; D006801:Humans; D006900:Hydroxylation; D007700:Kinetics; D011994:Recombinant Proteins / Q000378:metabolism
chemical_list: D000970:Antineoplastic Agents; D004791:Enzyme Inhibitors; D047309:Flavones; D005419:Flavonoids; D011994:Recombinant Proteins; D001189:Aryl Hydrocarbon Hydroxylases; C504573:CYP1A2 protein, human; C585496:CYP1B1 protein, human; D019363:Cytochrome P-450 CYP1A1; D019388:Cytochrome P-450 CYP1A2; D065633:Cytochrome P-450 CYP1B1; C023717:acacetin