The Effects Of Nilotinib Combined With Arsenic Trioxide On Proliferation And Apoptosis Of K562 Cells

Objective: To observe the apoptosis, proliferation and expression of BCR-ABL gene in K562 cells after treatment of Nilotinib(AMN107) combined with Arsenic Trioxide(ATO). Tish study intended to explore the possible synergistic effect and its mechanism between the two drugs and provide theoretical evidence for new therepy of Chronic Myelocytic Leukemia.Methods :K562 cells were cultured in vitro and seperated into experimental group and control group. The experimental group included AMN107 treatment group, ATO treatment group, and AMN107+ ATO treatment group. After treated with different concentrations of AMN107, ATO, AMN107+ ATO, K562 cells were collected to study proliferation, apoptosis, and cell cycle using MTT and FCM. Moreover, the expression of BCR-ABL was deceted by RT-PCR.The data was analysis by SPSS13.0 statistical software, with P<0.05 for the test of significance level.Results:1 The effect of AMN107 and ATO on the proliferation of K562 cellsDifferent concentrations of AMN107 treated with the K562 cells, the proliferation inhibitory rate was increased with the increasing concentration of AMN107(P<0.05). At the same concentration, AMN107 acted on the K562 cells for differentiation over time, the proliferation inhibitory rate was increased with the time extension(P<0.05).Different concentrations of ATO treated with the K562 cells, the proliferation inhibitory rate was increased with the increasing concentration of ATO(P<0.05). At the same concentration, ATO acted on the K562 cells for differentiation over time, the proliferation inhibitory rate was increased with the time extension(P<0.05).AMN107 combined with ATO treated K562 cells for differentiation over time, the proliferation inhibitory rate was increased with the time extension, it can achieve IC50 sooner than used AMN107 or ATO alone(P<0.05). Meanwhile, the combination groups had higher inhibitory rate than used AMN107 or ATO alone(P<0.05).2 The effect of AMN107 and ATO on apoptosis of K562 cells1μM ATO acted on K562 cells after 48 h, the apoptosis rate had no significant difference compared with control group(P>0.05). 2.5μM and 5.0μM ATO treated with K562 cells after 48 h, the apoptosis rate was much higher than control group(P<0.05), indicating that ATO induced cell apoptosis in a dose-dependent pattern.Different concentrations of AMN107 acted on the K562 cells, the apoptosis rate was increased with the increasing concentration of AMN107(P<0.05).AMN107 combined with ATO acted on K562 cells had higher apoptosis rate than used AMN107 or ATO alone(P<0.05).3 The effect of ATO on the cell cycle of K562 cellsDifferent concentrations of ATO acted on K562 cells, the percentage of G0/G1 phase was gradually increased with the increasing concentration of ATO, and the percentage of S and G2/M phase was decreased(P<0.05).4 The effects of AMN107 and ATO on the expression of BCR-ABL gene of K562 cellsAt the same time, different concentrations of AMN107 acted on the K562 cells, the expression of BCR-ABL genes were decreased with the increasing concentration of AMN107(P<0.05). At the same concentration, AMN107 acted on the K562 cells for differentiation over time, the expression levels of BCR-ABL genes were decreased with the time extension(P<0.05).At the same time, different concentrations of ATO acted on the K562 cells, the expression of BCR-ABL genes were decreased with the increasing concentration of ATO(P<0.05). At the same concentration, ATO acted on the K562 cells for differentiation over time, the expression levels of BCR-ABL genes were decreased with the time extension(P<0.05).At the same concentration, AMN107 combined with ATO acted on K562 cells for differentiation over time, the expression levels of BCR-ABL genes were decreased with the time extension(P<0.05). AT the same time, the combination groups could inhibit the expression levels of BCR-ABL genes deeper than used AMN107 or ATO alone(P<0.05).Conclusions:1 AMN107 could inhibit proliferation and induce apoptosis of K562 cells in a dose- and time-dependent pattern. This maight be associatedwith the degradation of BCR-ABL.2 ATO could inhibit proliferation and induce apoptosis of K562 cells in a dose- and time-dependent pattern. This maight be contributed byG0/G1 phase arresting and degradation of BCR-ABL.3 AMN107 combined with ATO increased the inhibitory effects in K562 cells than single agent, indicating that the two drugs had some synergistic effects. They maight down-regulate the expression of BCR-ABLthrough different pathways.