去甲斑蝥素和紫杉醇联合诱导白血病细胞K562凋亡

目的探讨去甲斑蝥素(norcantharidin,NCTD)和紫杉醇(paclitaxel,PTX)联合诱导白血病细胞K562凋亡的效应及机制。方法采用流式细胞术分析细胞凋亡和线粒体膜电位;采用免疫印迹技术检测细胞内凋亡相关信号分子Bim、Bax和Bcl-2表达。结果 7.5μmol/L NCTD单独作用可诱导(2.6±0.7)%白血病细胞K562发生凋亡;0、2.5、5和10nmol/L的PTX诱导细胞凋亡的百分率分别为(0.8±0.3)%(、4.7±1.9)%(、7.2±2.6)%和(9.4±2.9)%;而NCTD(7.5μmol/L)与PTX联合作用(2.55、和10 nmol/L)后,细胞凋亡率分别增高至(8.5±2.2)%(、19.3±3.1)%和(23.4±4.1)%。药物联合后Bim和Bax表达增强,而Bcl-2表达减少。结论 NCTD通过线粒体途径凋亡信号的转导,增强PTX诱导K562细胞凋亡的效应。

Norcantharidin increases leukemic cells K562 sensitivity to paclitaxel-induced apoptosis

Objective To study the apoptosis promoting effect of norcantharidin（NCTD） combined with paclitaxel on leukemic cells K562 and its mechanism.Methods Cell apoptosis and mitochondrial membrane potential（MMP） were measured by flow cytometry.The expression of apoptosis-related molecules Bim,Bax and Bcl-2 was detected by Western blot assay.Results 7.5 μmol/L NCTD caused apoptosis in（2.6±0.7）% of K562 cells.The apoptosis rate induced by different concentrations of paclitaxel（2.5,5 and 10 nmol/L） was（0.8±0.3）%,（4.7±1.9）%,（7.2±2.6）%,and（9.4±2.9）%,respectively.The apoptosis rate was increased to（8.5±2.2）%,（19.3±3.1）% and（23.4±4.1）% by the same concentrations of paclitaxel combined with 7.5 μmol/L NCTD.NCTD promoted paclitaxel-induced mitochondrial damage.Compared with those treated by paclitaxel or NCTD alone,the expression of Bim and Bax increased in cells treated by paclitaxel combined with NCTD while the level of Bcl-2 decreased.Conclusions NCTD promotes apoptosis signaling in K562 cells treated by paclitaxel.Thus,cell apoptosis is increased by paclitaxel combined with NCTD.