title: The 4'-O-benzylated doxorubicin analog WP744 overcomes resistance mediated by P-glycoprotein, multidrug resistance protein and breast cancer resistance protein in cell lines and acute myeloid leukemia cells.
abstract: BACKGROUND
  The synthetic 4'-O-benzylated doxorubicin analog WP744 was designed to abrogate transport by the multidrug resistance (MDR)-associated ATP-binding cassette (ABC) proteins P-glycoprotein (Pgp) and multidrug resistance protein (MRP-1). We compared its uptake and cytotoxicity with those of doxorubicin and daunorubicin in cell lines overexpressing Pgp, MRP-1 or breast cancer resistance protein (BCRP) and in acute myeloid leukemia (AML) cells.
  
  
  METHODS
  Cellular uptake was studied by flow cytometry and cytotoxicity in 96-h 96-well cultures in cell lines overexpressing Pgp, MRP-1 or wild type (BCRP(R482)) or mutant (BCRP(R482T), BCRP(R482G)) BCRP and in pre-treatment AML marrow cells.
  
  
  RESULTS
  Uptake and cytotoxicity of WP744 were consistently greater than those of doxorubicin and daunorubicin at equimolar concentrations in all cell lines studied and in AML cells.
  
  
  CONCLUSIONS
  WP744 overcomes transport by Pgp, MRP-1 and BCRP in cell lines and AML cells and is a promising agent for clinical development in AML and other malignancies with broad-spectrum multidrug resistance.
authors.affiliation: Department of Medicine, Roswell Park Cancer Institute, Buffalo, NY, USA.
authors.forename: Tracy A
authors.initials: TA
authors.lastname: Brooks
authors.forename: Kieran L
authors.initials: KL
authors.lastname: O'Loughlin
authors.forename: Hans
authors.initials: H
authors.lastname: Minderman
authors.forename: Brian N
authors.initials: BN
authors.lastname: Bundy
authors.forename: Laurie A
authors.initials: LA
authors.lastname: Ford
authors.forename: Michael R
authors.initials: MR
authors.lastname: Vredenburg
authors.forename: Ralph J
authors.initials: RJ
authors.lastname: Bernacki
authors.forename: Waldemar
authors.initials: W
authors.lastname: Priebe
authors.forename: Maria R
authors.initials: MR
authors.lastname: Baer
mesh_terms: D020168:ATP Binding Cassette Transporter, Subfamily B, Member 1 / Q000235:genetics / Q000502:physiology*; D000070997:ATP Binding Cassette Transporter, Subfamily G, Member 2; D018528:ATP-Binding Cassette Transporters / Q000235:genetics / Q000502:physiology*; D000328:Adult; D000368:Aged; D018943:Anthracyclines / Q000378:metabolism / Q000494:pharmacology*; D000903:Antibiotics, Antineoplastic / Q000378:metabolism; D000970:Antineoplastic Agents / Q000378:metabolism / Q000494:pharmacology*; D045744:Cell Line, Tumor; D002470:Cell Survival / Q000187:drug effects; D003630:Daunorubicin / Q000378:metabolism; D004317:Doxorubicin / Q000378:metabolism; D019008:Drug Resistance, Neoplasm / Q000187:drug effects*; D005260:Female; D005453:Fluorescence; D006801:Humans; D007951:Leukemia, Myeloid / Q000473:pathology*; D008297:Male; D008875:Middle Aged; D009363:Neoplasm Proteins / Q000235:genetics / Q000502:physiology*
chemical_list: C116614:ABCG2 protein, human; D020168:ATP Binding Cassette Transporter, Subfamily B, Member 1; D000070997:ATP Binding Cassette Transporter, Subfamily G, Member 2; D018528:ATP-Binding Cassette Transporters; D018943:Anthracyclines; D000903:Antibiotics, Antineoplastic; D000970:Antineoplastic Agents; D009363:Neoplasm Proteins; C451735:WP 744; D004317:Doxorubicin; D003630:Daunorubicin