JNK信号通路受抑制的人白血病K562/ADR细胞对尼洛替尼敏感性

Sensitivity of human leukemia K562/ADR cells with inhibited JNK signaling pathway to nilotinib

目的观察JNK信号通路受到抑制的人白血病K562/ADR细胞对尼洛替尼的敏感性。方法培养人白血病敏感细胞株K562和耐阿霉素细胞株K562/ADR,采用CCK-8法测算尼洛替尼对细胞的半抑制浓度(IC_(50))及耐药指数。用4μg/m L的SP600125抑制K562/ADR细胞JNK信号通路后进行尼洛替尼处理,CCK-8法测算细胞尼洛替尼IC_(50)。将K562/ADR细胞分为对照组、尼洛替尼组、联合组,对照组未处理,尼洛替尼组采用20μmol/L尼洛替尼处理,联合组先用4μg/m L SP600125预处理2 h,再用20μmol/L尼洛替尼处理,荧光定量PCR检测各组细胞内MDR1基因,Western blot法检测各组细胞内P-糖蛋白(P-gp)。结果 K562/ADR细胞对尼洛替尼的耐药指数为K562细胞的19.58倍。抑制JNK信号通路后,尼洛替尼对K562/ADR细胞的IC_(50)由(12.53±0.11)μmol/L下降到(6.77±0.24)μmol/L(P<0.05)。对照组、尼洛替尼组、联合组K562/ADR细胞MDR1 mRNA相对表达量分别为0.967 8±0.006 2、0.513 6±0.012 4、0.267 1±0.008 7,P-gp相对表达量分别为1.007 4±0.004 1、0.596 1±0.013 6、0.363 7±0.006 9,两两组间比较,P均<0.05。结论 JNK信号通路受抑制的人白血病K562/ADR细胞对尼洛替尼敏感性增加,这与抑制JNK信号通路可降低K562/ADR细胞中MDR1基因的表达有关。

Objective To observe the influence of inhibiting JNK signaling pathway on the sensitivity of K562/ADR cells to nilotinib. Methods The inhibitory concentration （ICs0） and resistance index of K562 cells and K562/ADR cells to nilotinib was measured by CCK-8 assay. K562/ADR cells were exposed to nilotinib after JNK signaling pathway was in- hibited by 4 Ixg/mL SP600125. CCK-8 assay was used to detect the IC50. K562/ADR cells were divided into the control group, nilotinib group and the combination group. The control group was not treated, nilotinib group was treated with 20 I^mol/L nilotinib, and the combination group was first treated with 4 p,g/mL SP600125 for 2 h, and then treated with 20 txmol/L nilotinib. The MDR1 gene was detected by real-time PCR. The P-glyeoprotein （P-g＇p） was detected by Western blotting. Results The resistance index of K562/ADR cells to nilotinib was 19.58 times higher than that of K562 cells. The IC50 of K562/ADR cells to nilotinib decreased from （ 12.53 ~ 0.11 ） p^mol/L to （6.77 -＋ 0.24） Ixmol/L after inhibi- tion of JNK signaling pathway （P 〈 0.05 ）. The relative expression of MDR1 mRNA in K562/ADR cells was 0. 967 8±0.006 2, 0. 513 6 ± 0.012 4, and 0. 267 1±0. 008 7 in the control group, nilotinib group and the combination group; the relative expression of P-gp was 1. 007 4± 0. 004 1,0. 596 1± 0. 013 6, and 0.363 7 ± 0.006 9, respectively; and significant difference was found between every two groups （ all P 〈 0.05 ）. Conclusion The sensitivity of human leukemia K562/ ADR cells with inhibited JNK signaling pathway to nilotinib is increased, which is associated with that the inhibition of JNK signaling pathway can decrease the expression of MDR1 gene in K562/ADR cells.