Study on the mechanism of luteolin reversing multidrug resistance in leukemia K562/ADR cells / 天津医药

ABSTRACT

Objective To investigate the mechanism of luteolin's(Lut)reversal effect on multidrug resistance of chronic myeloid leukemia K562/ADR cells.Methods CCK-8 assay was used to detect drug resistance in K562 and K562/ADR cells 24 hours after treatment with different doses of adriamycin(ADR).CCK-8 assay was used to assess the cytotoxicity and sensitizing effect of Lut on ADR after K562/ADR cells were treated with Lut alone or in combination with ADR for 24 hours.K562/ADR cells in logarithmic growth phase were separated into three group:0μmol/L Lut,2μmol/L and 4μmol/L Lut groups.ADR accumulation in cells was measured using flow cytometry.Nuclear factor erythroid-2-related factor 2(Nrf2),multidrug resistance associated protein 1(MRP1),P-glycoprotein(P-gp)and glutathione-S-transferase-PI(GST-pi)mRNA and protein expressions were identified using RT-PCR and Western blot assay.Glutathione(GSH)kit was used to detect intracellular GSH content.Results Compared with K562 cells,K562/ADR cell line was significantly resistant to ADR,and the drug resistance was 53.69 times.K562/ADR cell proliferation was decreased to variable degrees by different doses of Lut when compared to the 0μmol/L Lut group(P＜0.05).The proliferation inhibition rates of K562/ADR cells treated with 2 and 4μmol/L Lut were less than 10%,indicating that the concentration of Lut was non-toxic.Compared with the 0 μmol/L Lut group,the 2 μmol/L Lut group and the 4 μmol/L Lut group showed significantly increased ADR growth inhibition rate on K562/ADR and increased accumulation of ADR in cells,improved the reversal resistance fold,and decreased GSH content in cells.MRP1,P-gp,GST-pi and Nrf2 mRNA and protein expression were reduced in cells(P＜0.05).The effect of 4 mol/L Lut was greater than that of 2 mol/L Lut.Conclusion Lut may decrease K562/ADR cell proliferation and reverse ADR medication resistance.The mechanism could be connected to the downregulation of Nrf2,MRP1,P-gp and GST-pi expression,which leads to an increase in ADR accumulation in K562/ADR cells.