PDCD4对DAP5表达及大肠癌细胞凋亡的影响

【摘要】目的 探讨程序性死亡基因4(PDCD4)对死亡相关蛋白5（DAP5) 的表达及对人大肠癌细胞系LOVO凋亡的影响。方法 构建重组真核表达载体pFLAG/PDCD4，转染人大肠癌细胞LOVO，G418（500 mg/L）筛选获得稳定表达PDCD4的细胞系。RT-PCR及Western blotting检测LOVO细胞中PDCD4的mRNA及蛋白表达，流式细胞仪检测LOVO细胞凋亡情况，Western blotting检测LOVO细胞DAP5表达的变化。结果 成功建立稳定表达PDCD4的大肠癌 细胞LOVO-pFLAG/PDCD4。转染PDCD4 的LOVO-pFLAG/PDCD4 组与空白对照LOVO 组、转染空载质粒的LOVO-pFLAG组相比，PDCD4蛋白表达和mRNA水平明显升高（P < 0.01）；细胞凋亡率明显增加（P < 0.01）；同时伴有DAP5蛋白表达明显升高（P < 0.01）。结论PDCD4能够诱导大肠癌细胞LOVO的凋亡，其机制可能与上调DAP5的表达有关。

Effects of Programmed Cell Death 4 Gene on Expression of Death Associated Protein 5 and Apoptosis in Colon Cancer Cells

Abstract]ObjectiveTo investigate the effect of exogenous programmed cell death4(PDCD4) gene on the expres-sion of death associated protein5(DAP5) and apoptosis of human colorectal cancer cell LOVO, and involved mechanisms thereof.MethodsRecombinant eukaryotic plasmid pFLAG/PDCD4was constructed and transfected into human colorectal cancer cell LOVO. Cells stably expressing PDCD4were established by G418selection (500mg/L). The levels of PDCD4protein and mRNA were analyzed by RT-PCR and Western blotting. The apoptotic cells were measured by flow cytometry, and protein expression of DAP5was detected by Western blotting.Results LOVO-pFLAG/PDCD4cell line was successfully es-tablished by G418selection. Compared to non-transfection and mock-transfection group, the levels of PDCD4mRNA and protein were significantly increased, the cell apoptosis ratio was enhanced and the expression of DAP5protein was increased in transfection group (P<0.01).Conclusion PDCD4could induce apoptosis of human colorectal cancer LOVO cells, which mechanism might be involved in up-regulating DAP5protein.