title: [P-glycoprotein expression in hematological malignancies].
abstract: To clarify the common characteristics among P-glycoprotein (P-gp)-expressing hematological malignancies and whether chemotherapies could or could not induce P-gp expression, we analyzed P-gp/MDR1 expression in tumor cells from 200 Japanese patients (104 with acute myeloblastic leukemia (AML); 30 with acute lymphoblastic leukemia (ALL); 66 with mature lymphoid malignancies). Functional P-gp expression was examined by Rhodamine-123 efflux test, and estimated with the data by RT-PCR method. In mature lymphoid malignancies, the cells of T or natural killer (NK) cell malignancies frequently expressed P-gp/MDR1. In AML, frequent P-gp/MDR1 expression was associated with the expression of CD7 or c-kit and with 8; 21 chromosomal translocation (p < 0.01), which were thought to be the characteristics of the hematopoietic stem cell. Though the expression of P-gp/MDR1 was more frequent at onset than at relapse phase, the increase is thought to result from the expansion of blastic fraction expressing P-gp/MDR1. In ALL, P-gp/MDR1 expression was not frequent in B-cell precursor lineage (three of eighteen patients), but the incidence was high in CD7(+) surface CD3(-) cases (seven of the cases). These results indicate P-gp/MDR1 expression is more frequently in the tumor of T, NK cell and stem cell, reflecting the characteristics of its normal counterpart.
authors.affiliation: Second Department of Internal Medicine, Mie University School of Medicine.
authors.forename: M
authors.initials: M
authors.lastname: Yamaguchi
authors.forename: M
authors.initials: M
authors.lastname: Mizutani
authors.forename: H
authors.initials: H
authors.lastname: Miwa
authors.forename: K
authors.initials: K
authors.lastname: Kita
mesh_terms: D020168:ATP Binding Cassette Transporter, Subfamily B, Member 1 / Q000378:metabolism*; D018432:Drug Resistance, Multiple / Q000235:genetics; D006801:Humans; D015470:Leukemia, Myeloid, Acute / Q000188:drug therapy / Q000378:metabolism*
chemical_list: D020168:ATP Binding Cassette Transporter, Subfamily B, Member 1