左旋门冬酰胺酶与盐霉素联合作用对急性T淋巴细胞白血病Jurkat细胞株增殖凋亡的影响

 目的：研究左旋门冬酰胺酶（L-asparaginase，L-ASP）与盐霉素（salinomycin，Sal）联合作用对急性T淋巴细胞白血病Jurkat细胞株增殖和凋亡的影响及其机制。方法：CCK-8试剂盒检测细胞增殖情况；Western blotting方法检测凋亡相关蛋白Bcl-2、caspase-3、caspase-8、caspase-9及细胞色素C表达的变化；流式细胞术分析各实验组细胞凋亡率之间的差别。结果：不同浓度的L-ASP和Sal单独处理Jurkat细胞株后均显示出明显的增殖抑制作用，L-ASP的IC50为812 IU/L,Sal 的IC50为0.75 μmol/L。而两药联合使用的增殖抑制作用更显著（P<0.05）；合用指数计算公式结果显示两药为协同作用。Western blotting 显示联合用药组与L-Asp、Sal单独处理组相比，Bcl-2蛋白表达明显减少，caspase-3、caspase-8、caspase-9和胞浆细胞色素C水平明显增高；干预48 h后行流式细胞术检测结果显示L-ASP（25 IU/L）单独处理组和Sal（0.5μmol/L）单独处理组细胞凋亡率分别为（7.11±0.23）%和（25.43±047）%，与对照组（6.67±0.13）%比较差别有统计学意义（P＜0.05)，联合用药组细胞凋亡率（39.12±1.97）%分别与L-ASP、Sal单独处理组比较，差别有统计学意义（P＜0.05)。结论：左旋门冬氨酸酶与盐霉素联合作用于Jurkat细胞具有协同抑制增殖和诱导凋亡的作用。

Effects of salinomycin combined with L-asparaginase on proliferation and apoptosis of human acute T-cell leukemia Jurkat cells

AIM:To investigate the effects of salinomycin alone or in combination with L-asparaginase on the growth and apoptosis of human acute T-cell leukemia Jurkat cells, and the possible mechanism. METHODS:The growth of Jurkat cells was tested by Cell Counting Kit-8 in vitro. The levels of cytochrome C, Bcl-2, caspase-3, caspase-8 and caspase-9 were measured by Western blotting. Flow cytometry was used to assay cell apoptosis. RESULTS:Salinomycin or L-asparaginase alone inhibited the growth of Jurkat cells in a dose-dependent manner. The IC50 value of L-asparaginase was 8.12 IU/L, while that of salinomycin was 0.75 μmol/L. Salinomycin combined with L-asparaginase induced more significant inhibition of cell proliferation (P<0.05). Western blotting showed that the expression of Bcl-2 protein in combination group was significantly reduced, and the expression of caspase-3, caspase-8, caspase-9 and cytochrome C was significantly increased (P<0.05). Flow cytometry showed that the apoptotic rates of Jurkat cells incubated with salinomycin (0.5 μmol/L), L-asparaginase (2.5 IU/L) and both drugs for 48 h were (7.11±0.23)%, (25.43±0.47)% and (39.12±1.97)%, respectively, and significantly higher than that in control group ［(6.67±0.13)%, P<0.05］.CONCLUSION: Salinomycin synergizes with L-asparaginase-induced cytotoxicity in vitro, and the combined treatment with salinomycin and L-asparaginase induces the apoptosis of Jurkat cells.