ABT737通过激活JNK/c-Jun通路上调Bim诱导宫颈癌细胞凋亡

【目的】探讨JNK/c-Jun信号通路激活Bim在ABT737诱导宫颈癌细胞凋亡中的作用。【方法】用MTT法检测ABT-737对人宫颈癌Hela细胞的生长抑制作用;用流式细胞术检测细胞凋亡率;用Western blot方法检测JNK、phospho-JNK、c-Jun、phospho-c-Jun以及Bim蛋白的表达;用RT-PCR检测Bim在mRNA水平的变化;用JNK特异性抑制剂SP600125和siRNA瞬时转染抑制JNK及c-Jun的活性。 【结果】ABT-737能抑制Hela细胞的生长,诱导HeLa细胞发生凋亡。ABT737可激活JNK激酶活性其下游靶分子c-Jun,凋亡相关基因Bim在mRNA水平和蛋白水平的表达也随之上调。应用JNK特异性抑制剂SP600125和靶向JNK及c-Jun的siRNA抑制JNK或c-Jun的活性或表达后,ABT737诱导的Bim上调及细胞凋亡亦被有效阻断。【结论】ABT737通过JNK/c-Jun信号通路上调凋亡相关基因Bim的表达,诱导HeLa细胞发生凋亡。

Role of JNK-mediated Bim Expression in ABT737 -induced Apoptosis in HeLa Cells

【Objective】 ABT-737 is a BH3 mimetic small molecule inhibitor that can effectively inhibit the activity of antiapoptotic Bcl-2 family proteins including Bcl-2, Bcl-xL and Bcl-w, and further enhances the effect of apoptosis. We explored the pivotal role of JNK-mediated Bim expression in ABT737 -induced apoptosis in HeLa cells. 【Methods】 Annexin V-PI staining was used to assess the apoptosis. The expression of JNK, phospho-JNK, c-Jun, phospho-c-Jun, Bim were detected using Western blot analysis. RT-PCR was used to detect the mRNA level of Bim. JNK specific inhibitor SP600125 or siRNA against JNK c-Jun were used to block activation of JNK. 【Results】 ABT737 significantly inhibited cell growth of HeLa cells with IC50 value of 15.7 μmol/L. ABT737 induced apoptosis in HeLa cells. JNK was activated in cells exposed to ABT737 and the phosphorylation of c-Jun also increased. In the meantime, the expression of Bim was up-regulated in HeLa cells. The up-regulation of Bim expression and apoptosis induced by ABT737 were blocked by SP600125 or small interfering RNA directed against JNK or c-Jun. 【Conclusion】 JNK/c-Jun pathway mediates Bim up-regulation in apoptosis induced by ABT737.