title: Circumvention of multidrug resistance by a quinoline derivative, MS-209, in multidrug-resistant human small-cell lung cancer cells and its synergistic interaction with cyclosporin A or verapamil.
abstract: OBJECTIVE
  To develop a clinically useful approach to circumvent P-glycoprotein (P-gp)-mediated multidrug resistance (MDR) in MDR human small-cell lung cancer (SCLC), we examined the ability of a novel quinoline compound, MS-209, to reverse MDR by inhibition of P-gp function in combination with other MDR-reversing drugs using a cytotoxicity assay.
  
  
  RESULTS
  We established MDR human SCLC cells by culture in medium with gradually increasing concentrations of adriamycin (ADM). Compared with the parental human SCLC cells, SBC-3, the MDR variant SBC-3 cells obtained (SBC-3/ADM) were highly resistant to various chemotherapeutic agents due to P-gp expression. MS-209 reversed the resistance to ADM and vincristine (VCR) of SBC-3/ADM and H69/VP cells in a dose-dependent manner. Moreover, MS-209 in combination with cyclosporin A (CsA) or verapamil (VER) synergistically enhanced the antitumor effects of ADM and VCR on SBC-3/ADM cells. MS-209 restored ADM incorporation and this effect was enhanced by CsA and VER, suggesting that these synergistic effects were due to competitive inhibition of P-gp function.
  
  
  CONCLUSIONS
  MS-209 in combination with CsA or VER might increase the efficacy of these chemotherapeutic agents against MDR human SCLC cells.
authors.affiliation: Third Department of Internal Medicine, The University of Tokushima School of Medicine, Japan.
authors.forename: P
authors.initials: P
authors.lastname: Shrivastava
authors.forename: M
authors.initials: M
authors.lastname: Hanibuchi
authors.forename: S
authors.initials: S
authors.lastname: Yano
authors.forename: P
authors.initials: P
authors.lastname: Parajuli
authors.forename: T
authors.initials: T
authors.lastname: Tsuruo
authors.forename: S
authors.initials: S
authors.lastname: Sone
mesh_terms: D020168:ATP Binding Cassette Transporter, Subfamily B, Member 1 / Q000378:metabolism; D000970:Antineoplastic Agents / Q000494:pharmacology / Q000627:therapeutic use; D018288:Carcinoma, Small Cell / Q000188:drug therapy* / Q000378:metabolism / Q000473:pathology; D016572:Cyclosporine / Q000494:pharmacology / Q000627:therapeutic use*; D018432:Drug Resistance, Multiple; D019008:Drug Resistance, Neoplasm; D004357:Drug Synergism; D006801:Humans; D008175:Lung Neoplasms / Q000188:drug therapy* / Q000378:metabolism / Q000473:pathology; D011804:Quinolines / Q000494:pharmacology / Q000627:therapeutic use*; D014407:Tumor Cells, Cultured; D014700:Verapamil / Q000494:pharmacology / Q000627:therapeutic use*
chemical_list: D020168:ATP Binding Cassette Transporter, Subfamily B, Member 1; D000970:Antineoplastic Agents; D011804:Quinolines; C087719:dofequidar; D016572:Cyclosporine; D014700:Verapamil