目的 探讨X连锁凋亡抑制蛋白（XIAP）抑制剂蒽贝素抑制人胰腺癌细胞Mia PaCa-2凋亡的作用及其可能机制。方法 MTT法和流式细胞术检测不同剂量蒽贝素对Mia PaCa-2细胞增殖和凋亡的影响；RT-PCR法对蒽贝素处理前后Mia PaCa-2细胞中XIAP基因的表达进行检测。Western blotting方法检测蒽贝素作用后细胞XIAP、Caspase 3、促凋亡蛋白Bax和抗凋亡蛋白Bcl-2表达的变化。结果 蒽贝素对人胰腺癌细胞增殖具有显著抑制作用（P<0.05），经不同剂量蒽贝素处理后Mia PaCa-2细胞凋亡率明显增高，与未处理组比较差异具有显著性（P<0.01）；RT-PCR显示对照组细胞中XIAP的-△△CT值是实验组的11.31倍；经蒽贝素作用24 h后，Mia PaCa-2细胞出现Caspase 3裂解片段，且Bax/Bcl-2比值增大。结论 蒽贝素在体外可显著抑制Mia PaCa-2细胞增殖，诱导细胞凋亡，其机制可能是通过拮抗XIAP的作用，激活Caspase相关性的细胞凋亡内源性途径而诱导人胰腺癌细胞发生凋亡。

Objective To discuss the effect of X-linked inhibitor of apoptosis (XIAP) inhibitor embelin on the apoptosis of pancreatic cancer Mia PaCa-2 cells and its possible mechanism. Methods The growth suppression and the apoptotic rate of embelin on Mia PaCa-2 cells were evaluated by MTT assay and flow cytometry. Real-time quantitative reverse transcriptionpolymerase chain reaction (RT-PCR) method was used to detect the expression of XIAP gene in Mia PaCa-2 cells with or without treatment of embelin. Western blotting analysis was performed to assess the expression of XIAP, Caspase 3, pro-apoptotic factor Bax as well as the pro-survival factor Bcl-2. Results Embelin inhibited the proliferation of the pancreatic cancer cells (P<0.05). The apoptosis of Mia PaCa-2 cells were significantly increased after embelin treatment at different concentration as compared with that in the control group (P<0.01). Furthermore, the -△△CT value of XIAP in the control group was 11.31 times as much as that in the treatment group. The cleavage of Caspase 3 was observed after 24 h treated with embelin. Moreover, Bax expression was upregulated while Bcl-2 levels were decreased. Conclusion Embelin can significantly inhibit the proliferation of Mia PaCa-2 cells, induce the apoptosis of Mia PaCa-2 cells by antagonizing the endogenous XIAP pathway that activates caspase-dependent apoptosis in Mia PaCa-2 cells.

天津市卫生局重点课题资助项目（2012KR06）