title: Increased expression of the breast cancer resistance protein (BCRP) in relapsed or refractory acute myeloid leukemia (AML).
abstract: Expression of the multidrug resistance proteins P-glycoprotein, encoded by the MDR1 gene, multidrug resistance-associated protein (MRP1) and the lung resistance-related protein or major vault protein (LRP/MVP) is associated with clinical resistance to chemotherapy in acute myeloid leukemia (AML). Recently, the breast cancer-resistant protein (BCRP), the equivalent of mitoxantrone-resistant protein (MXR) or placental ABC transporter (ABCP), was described in AML. We investigated MDR1, MRP1, LRP/MVP and BCRP mRNA expression simultaneously in 20 paired clinical AML samples from diagnosis and relapse or refractory disease, using quantitative Taqman analysis. In addition, standard assays for P-glycoprotein expression and function were performed. BCRP was the only resistance protein that was expressed at a significantly higher RNA level (median 1.7-fold, P = 0.04) at relapsed/refractory state as compared to diagnosis. In contrast, LRP/MVP mRNA expression decreased as disease evolved (P = 0.02), whereas MDR1 and MRP1 mRNA levels were not different at relapse as compared to diagnosis. Also, at the protein level no difference of MDR1 between diagnosis and relapse was found. A significant co-expression of BCRP and MDR1 was found at diagnosis (r = 0.47, P = 0.04). The present results suggest that BCRP, but not MDR1, MRP1 or LRP/MVP is associated with clinical resistant disease in AML.
authors: Department of Hematology, University Hospital, Erasmus University, Rotterdam, The Netherlands.
authors: M M
authors: MM
authors: van den Heuvel-Eibrink
authors: E A C
authors: EA
authors: Wiemer
authors: A
authors: A
authors: Prins
authors: J P P
authors: JP
authors: Meijerink
authors: P J M
authors: PJ
authors: Vossebeld
authors: B
authors: B
authors: van der Holt
authors: R
authors: R
authors: Pieters
authors: P
authors: P
authors: Sonneveld
mesh_terms: D020168:ATP Binding Cassette Transporter, Subfamily B, Member 1 / Q000235:genetics / Q000378:metabolism; D000070997:ATP Binding Cassette Transporter, Subfamily G, Member 2; D018528:ATP-Binding Cassette Transporters / Q000235:genetics / Q000378:metabolism* / Q000502:physiology; D000208:Acute Disease; D000293:Adolescent; D000328:Adult; D000368:Aged; D001854:Bone Marrow Cells / Q000473:pathology; D002648:Child; D002675:Child, Preschool; D018450:Disease Progression; D019008:Drug Resistance, Neoplasm; D006801:Humans; D007223:Infant; D007951:Leukemia, Myeloid / Q000188:drug therapy / Q000378:metabolism* / Q000473:pathology; D008875:Middle Aged; D027425:ATP-Binding Cassette, Sub-Family C Proteins / Q000235:genetics / Q000378:metabolism; D009363:Neoplasm Proteins / Q000235:genetics / Q000378:metabolism* / Q000502:physiology; D016133:Polymerase Chain Reaction; D012333:RNA, Messenger / Q000378:metabolism; D012008:Recurrence; D015854:Up-Regulation; D020394:Vault Ribonucleoprotein Particles / Q000235:genetics / Q000378:metabolism; D000099187:Major Vault Protein
chemical_list: D020168:ATP Binding Cassette Transporter, Subfamily B, Member 1; D000070997:ATP Binding Cassette Transporter, Subfamily G, Member 2; D018528:ATP-Binding Cassette Transporters; D027425:ATP-Binding Cassette, Sub-Family C Proteins; D009363:Neoplasm Proteins; D012333:RNA, Messenger; D020394:Vault Ribonucleoprotein Particles; D000099187:Major Vault Protein; C116614:ABCG2 protein, human; C421109:multidrug resistance-associated protein 1