title: [Reversal effect of berbamine on multidrug resistance of K562/A02 cells and its mechanism].
abstract: This preject is to explore the reversal efficacy of calmodulin antagonist berbamine (BBM) on multidrug resistance (MDR) and its mechanism. Human erythroleukemic cell line K562 and its adriamycin-resistant counterpart K562/A02 were used in the study. The cells were co-cultured with ADR and BBM in different concentrations. MTT assay was used to analyze the effect of BBM on cell growth inhibition. According to the MTT assay, the 50% inhibitory concentration (IC(50)), the multiples of drug resistance and increased sensitivity of ADR were calculated. The concentration of intracellular ADR and expression level of P-gp were detected by flow cytometry (FCM). The expression level of mdr1 mRNA and survivin mRNA was detected by semi-quantitative reverse transcriptase polymerase chain reaction (RT-PCR) with beta-actin as internal reference. The results showed that IC(50) of ADR in K562 and K562/A02 cells was 1.16 +/- 0.09 micro mol/L and 37.47 +/- 1.76 micro mol/L, respectively. The resistant multiple of K562/A02 cells to ADR was 32.30 higher than that of K562 cells. BBM increased the chemo-sensitivity of ADR in K562/A02 cells with dose-dependent relationship, i.e. when 5, 10 and 20 micro mol/L BBM was added in the culture the chemo-sensitivity of ADR was increased to 2.01-, 9.68-, and 41.18-fold (P < 0.01), respectively. After treating K562/A02 cells by 5 or 10 micro mol/L BBM for 2 hours the accumulation of intracellular ADR was increased to 1.41- and 1.52-fold (P < 0.01), respectively. Treating by BBM for 72 hours decreased 4.12% (P < 0.05) and 27.09% (P < 0.01) of P-gp expression, respectively, meanwhile down-regulated expression of mdr1 mRNA and survivin mRNA was found. In conclusion, BBM could increase intracellular concentration of ADR in K562/A02 that down-regulated expression level of mdr1 mRNA and P-gp and survivin so that the sensitivity of K562/A02 to ADR was increased significantly.
authors.affiliation: Department of Hematology The First Hospital, Peking University, Beijing 100034, China.
authors.forename: Yan-Qiu
authors.initials: YQ
authors.lastname: Han
authors.forename: Jia-Ying
authors.initials: JY
authors.lastname: Yuan
authors.forename: Yong-Jin
authors.initials: YJ
authors.lastname: Shi
authors.forename: Yan
authors.initials: Y
authors.lastname: Zhu
authors.forename: Shu-Lan
authors.initials: SL
authors.lastname: Wu
mesh_terms: D020168:ATP Binding Cassette Transporter, Subfamily B, Member 1 / Q000032:analysis; D000470:Alkaloids; D044182:Benzylisoquinolines / Q000494:pharmacology*; D002147:Calmodulin / Q000037:antagonists & inhibitors*; D002455:Cell Division / Q000187:drug effects; D004317:Doxorubicin / Q000493:pharmacokinetics / Q000494:pharmacology; D018432:Drug Resistance, Multiple; D019008:Drug Resistance, Neoplasm; D019450:Genes, MDR; D006801:Humans; D051034:Inhibitor of Apoptosis Proteins; D020014:K562 Cells; D007938:Leukemia / Q000188:drug therapy*; D008869:Microtubule-Associated Proteins / Q000235:genetics; D009363:Neoplasm Proteins; D012333:RNA, Messenger / Q000032:analysis; D000077022:Survivin
chemical_list: D020168:ATP Binding Cassette Transporter, Subfamily B, Member 1; D000470:Alkaloids; C107489:BIRC5 protein, human; D044182:Benzylisoquinolines; D002147:Calmodulin; D051034:Inhibitor of Apoptosis Proteins; D008869:Microtubule-Associated Proteins; D009363:Neoplasm Proteins; D012333:RNA, Messenger; D000077022:Survivin; D004317:Doxorubicin; C027870:berbamine