title: Expression of P-glycoprotein in adult T-cell leukemia cells.
abstract: We have examined the expression of P-glycoprotein (P-gp) in adult T-cell leukemia (ATL) samples from 25 patients. Based on immunoblotting with a monoclonal antibody against P-gp, C219, 8 of 20 ATL patients were P-gp positive at the initial presentation. All 6 patients at the relapsed stage were P-gp positive, and refractory to chemotherapy. The expression of MDR1 mRNA in P-gp-positive ATL cells was increased at the relapsed stage of one patient. P-gp of this patient was photolabeled with [3H]azidopine and the labeling was inhibited with nimodipine, vinblastine and progesterone. These results suggest that P-gp expressed in ATL cells from patients at relapsed stage has the same binding site(s) for the drugs as that in multidrug resistant cells, and is correlated with the refractory nature of the cells to chemotherapy.
authors.affiliation: Cancer Research Institute, Kagoshima University, Japan.
authors.forename: Y
authors.initials: Y
authors.lastname: Kuwazuru
authors.forename: S
authors.initials: S
authors.lastname: Hanada
authors.forename: T
authors.initials: T
authors.lastname: Furukawa
authors.forename: A
authors.initials: A
authors.lastname: Yoshimura
authors.forename: T
authors.initials: T
authors.lastname: Sumizawa
authors.forename: A
authors.initials: A
authors.lastname: Utsunomiya
authors.forename: K
authors.initials: K
authors.lastname: Ishibashi
authors.forename: T
authors.initials: T
authors.lastname: Saito
authors.forename: K
authors.initials: K
authors.lastname: Uozumi
authors.forename: M
authors.initials: M
authors.lastname: Maruyama
mesh_terms: D020168:ATP Binding Cassette Transporter, Subfamily B, Member 1; D000911:Antibodies, Monoclonal / Q000276:immunology; D001386:Azides; D001752:Blast Crisis / Q000378:metabolism; D002460:Cell Line; D004095:Dihydropyridines; D015973:Gene Expression Regulation, Leukemic; D006801:Humans; D015151:Immunoblotting; D015464:Leukemia, Myelogenous, Chronic, BCR-ABL Positive / Q000235:genetics / Q000378:metabolism; D015470:Leukemia, Myeloid, Acute / Q000235:genetics / Q000378:metabolism; D015458:Leukemia, T-Cell / Q000235:genetics* / Q000378:metabolism; D008198:Lymph Nodes / Q000378:metabolism / Q000473:pathology; D008562:Membrane Glycoproteins / Q000235:genetics* / Q000276:immunology / Q000378:metabolism; D009553:Nimodipine / Q000494:pharmacology; D016133:Polymerase Chain Reaction; D054198:Precursor Cell Lymphoblastic Leukemia-Lymphoma / Q000235:genetics / Q000378:metabolism; D011374:Progesterone / Q000494:pharmacology; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D014316:Tritium; D014747:Vinblastine / Q000494:pharmacology
chemical_list: D020168:ATP Binding Cassette Transporter, Subfamily B, Member 1; D000911:Antibodies, Monoclonal; D001386:Azides; D004095:Dihydropyridines; D008562:Membrane Glycoproteins; D012333:RNA, Messenger; D014316:Tritium; D011374:Progesterone; D009553:Nimodipine; D014747:Vinblastine; C041130:azidopine