title: Multidrug resistance gene (MDR1) polymorphisms correlate with imatinib response in chronic myeloid leukemia.
abstract: The human multidrug resistance gene (MDR1, ABCB1) codes for P-glycoprotein (P-gp) that affects the pharmacokinetics of many drugs. MDR1 single nucleotide polymorphisms (SNPs) are associated with drug clearance. Imatinib is a substrate of P-gp-mediated efflux. We investigated the MDR1 T1236C, G 2677T/A, and C3435T polymorphism in 52 patients with chronic myeloid leukemia treated with imatinib. The distribution of MDR1 1236, 2677, or 3435 genotypes was significantly different between the resistance patients and sensitivity patients. The resistance incidence correlated with the number of T alleles at locus 1236 and 3435. Resistance was higher for patients homozygous for the 1236T allele when compared to patients with CT/CC genotype groups (75% vs. 31.3%, P = 0.004). For the G2677T/A polymorphism, a better complete cytogenetic remission was observed for patients with genotype AG/AT/AA, when compared to other genotype groups (TT/GT/GG, P = 0.02). Patients with 3435 TT/CT genotypes showed a higher resistance when compared with patients with CC genotype (59.4% vs. 25%, P = 0.023). In conclusion, determination of 1236T, C3435T, and G2677T MDR1 polymorphisms might be useful in response prediction to therapy with imatinib in patients with CML.
authors.affiliation: Department of Hematology, Jiangsu Province Hospital, The First Affiliated Nanjing Medical University Hospital, Nanjing Medical University, 300 Guangzhou Rd, 210029 Nanjing, China.
authors.forename: Ling-Na
authors.initials: LN
authors.lastname: Ni
authors.forename: Jian-Yong
authors.initials: JY
authors.lastname: Li
authors.forename: Kou-Rong
authors.initials: KR
authors.lastname: Miao
authors.forename: Chun
authors.initials: C
authors.lastname: Qiao
authors.forename: Su-Jiang
authors.initials: SJ
authors.lastname: Zhang
authors.forename: Hai-Rong
authors.initials: HR
authors.lastname: Qiu
authors.forename: Si-Xuan
authors.initials: SX
authors.lastname: Qian
mesh_terms: D018435:ATP Binding Cassette Transporter, Subfamily B; D020168:ATP Binding Cassette Transporter, Subfamily B, Member 1 / Q000235:genetics*; D000293:Adolescent; D000328:Adult; D000368:Aged; D000970:Antineoplastic Agents / Q000627:therapeutic use*; D001549:Benzamides; D019008:Drug Resistance, Neoplasm / Q000235:genetics*; D005260:Female; D005838:Genotype; D006801:Humans; D000068877:Imatinib Mesylate; D015464:Leukemia, Myelogenous, Chronic, BCR-ABL Positive / Q000188:drug therapy* / Q000235:genetics*; D008297:Male; D008875:Middle Aged; D010879:Piperazines / Q000627:therapeutic use*; D011110:Polymorphism, Genetic / Q000235:genetics*; D011379:Prognosis; D011743:Pyrimidines / Q000627:therapeutic use*; D015996:Survival Rate; D055815:Young Adult
chemical_list: C513055:ABCB1 protein, human; D018435:ATP Binding Cassette Transporter, Subfamily B; D020168:ATP Binding Cassette Transporter, Subfamily B, Member 1; D000970:Antineoplastic Agents; D001549:Benzamides; D010879:Piperazines; D011743:Pyrimidines; D000068877:Imatinib Mesylate