title: Modulation of multidrug resistance protein 1 (MRP1/ABCC1)-mediated multidrug resistance by bivalent apigenin homodimers and their derivatives.
abstract: Here we showed that bivalency approach is effective in modulating multidrug resistance protein 1 (MRP1/ABCC1)-mediated doxorubicin (DOX) and etoposide (VP16) resistance in human 2008/MRP1 ovarian carcinoma cells. Flavonoid dimers bearing five or six ethylene glycol (EG) units with 6-methyl (4e, 4f) or 7-methyl (5e, 5f) substitution on the ring A of flavonoid dimers have the highest modulating activity for DOX against MRP1 with an EC(50) ranging from 73 to 133 nM. At 0.5 microM, the flavonoid dimer 4e was sufficient to restore DOX accumulation in 2008/MRP1 to parental 2008/P level. Lineweaver-Burk and Dixon plot suggested that it is likely a competitive inhibitor of DOX transport with a K(i) = 0.2 microM. Our data suggest that flavonoid dimers have a high affinity toward binding to DOX recognition site of MRP1. This results in inhibiting DOX transport, increasing intracellular DOX retention, and finally resensitizing 2008/MRP1 to DOX. The present study demonstrates that flavonoid dimers can be employed as an effective modulator of MRP1-mediated drug resistance in cancer cells.
authors.affiliation: Department of Applied Biology and Chemical Technology, The Hong Kong Polytechnic University, Hung Hum, Hong Kong, SAR.
authors.forename: Iris L K
authors.initials: IL
authors.lastname: Wong
authors.forename: Kin-Fai
authors.initials: KF
authors.lastname: Chan
authors.forename: Ka Hing
authors.initials: KH
authors.lastname: Tsang
authors.forename: Chi Yin
authors.initials: CY
authors.lastname: Lam
authors.forename: Yunzhe
authors.initials: Y
authors.lastname: Zhao
authors.forename: Tak Hang
authors.initials: TH
authors.lastname: Chan
authors.forename: Larry Ming Cheung
authors.initials: LM
authors.lastname: Chow
mesh_terms: D047310:Apigenin / Q000737:chemistry* / Q000494:pharmacology*; D001667:Binding, Competitive; D045744:Cell Line, Tumor; D019281:Dimerization; D004305:Dose-Response Relationship, Drug; D004317:Doxorubicin / Q000378:metabolism / Q000494:pharmacology; D018432:Drug Resistance, Multiple / Q000187:drug effects*; D005047:Etoposide / Q000494:pharmacology; D006801:Humans; D006878:Hydroxides / Q000737:chemistry; D042541:Intracellular Space / Q000187:drug effects / Q000378:metabolism; D027425:ATP-Binding Cassette, Sub-Family C Proteins / Q000037:antagonists & inhibitors / Q000378:metabolism*; D013329:Structure-Activity Relationship
chemical_list: D047310:Apigenin; D004317:Doxorubicin; D005047:Etoposide; D006878:Hydroxides; D027425:ATP-Binding Cassette, Sub-Family C Proteins; C031356:hydroxide ion; C421109:multidrug resistance-associated protein 1