Obviation of drug resistance and affinity purification of P-glycoprotein by isoquinolinesulfonamides.
A newly synthesized isoquinolinesulfonamide named H-85; N-[2-[N-formyl-N-[[3-(4-chlorophenyl)-2-propenyl] amino] ethyl]-5-isoquinolinesulfonamide was found to reverse drug resistance in multidrug resistant P388 murine leukemic cells (P388/ADR). The energy-dependent extrusion of [3H]vinblastine from P388/ADR-cells was significantly suppressed by 10 microM H-85 but not so the efflux from the sensitive P388 cells. A 140-kDa protein overexpressed in P388/ADR cells was photoaffinity labeled with a vinblastine analog; N-(P-azid-[3-125I]salicyl-N'-(beta-aminoethyl) vindesine and H-85 selectively inhibited photolabeling of the 140-kDa protein. This 140-kDa protein was purified to apparent homogeneity by succeeding steps of phosphocellulose, DEAE-cellulose, and W-66 (a derivative of H-85)-coupled sepharose chromatography. The purified 140-kDa protein proved to be immunopositive with the P-glycoprotein-specific monoclonal antibody, C219.
Department of Pharmacology, Nagoya University School of Medicine, Japan.
M
M
Hagiwara
S
S
Wakusawa
K
K
Miyamoto
H
H
Hidaka
D020168:ATP Binding Cassette Transporter, Subfamily B, Member 1; D000818:Animals; D002846:Chromatography, Affinity; D002848:Chromatography, DEAE-Cellulose; D004305:Dose-Response Relationship, Drug; D004351:Drug Resistance; D004591:Electrophoresis, Polyacrylamide Gel; D005260:Female; D066298:In Vitro Techniques; D007546:Isoquinolines / Q000494:pharmacology*; D007941:Leukemia P388 / Q000188:drug therapy*; D008562:Membrane Glycoproteins / Q000378:metabolism*; D051379:Mice; D014407:Tumor Cells, Cultured; D014747:Vinblastine / Q000378:metabolism / Q000627:therapeutic use
D020168:ATP Binding Cassette Transporter, Subfamily B, Member 1; D007546:Isoquinolines; D008562:Membrane Glycoproteins; C071449:H 85; D014747:Vinblastine