Role of murine double minute 2 in apoptosis of acute lymphoblastic leukemia EU-4 cells induced by berberine / 中华实用儿科临床杂志

ABSTRACT

Objective To explore the role of murine double minute 2 (MDM2) in apoptosis of acute lymphoblastic leukemia EU-4 cells induced by berberine.Methods EU-4 cells at logarithm growth phase were chosen to carry out the experiments.EU-4 cells were incubated with different doses of berberine for 72 hours,and the final doses of berberine were 0,1,10 and 100 μmoL/L,respectively.Then the apoptosis rate of EU-4 cells were detected by flow cytometry,and the expression levels of MDM2 protein were tested by Western blot.The levels of MDM2 gene were examined by means of real-time PCR at 0,24,48 and 72 hours after incubation of EU-4 cells with 100 μmol/L berberine,respectively.EU-4 cells in MDM2 small interfering RNA(siRNA) group were transfected with 150 nmol/L MDM2 siRNA,and the control siRNA group were transfected with 150 nmol/L control siRNA.The apoptosis rates of EU-4 cells were detected 48 hours after transfection by flow cytometry.Results The apoptosis rates of EU-4 cells were increased in a dosedependent manner,and the highest apoptosis rate was up to(60.13 ± 4.21)％,which was incubated with 100 μmol/L berberine.Significant differences were found in all groups (F =280.56,P ＜ 0.05).Berberine treatment suppressed the protein expression of MDM2 in a dose-dependent manner(F =73.82,P ＜ 0.01).The mRNA expression of MDM2 was inhibited in a time-dependent manner by 100 μmol/L berberine(F =45.37,P ＜0.01).The apoptosis rates of control siRNA group and MDM2 siRNA group were(11.09 ± 1.63) ％ and (29.84 ± 1.75) ％,respectively.Significant difference was found between the 2 groups (t =-13.57,P ＜ 0.01).Conclusions Berberine can inhibit the expression of MDM2 in a dose-and time-dependent manner,which may be one of the mechanisms of apoptosis induced by berberine in leukemia cells.