肿瘤坏死因子相关凋亡诱导配体的抗胰腺癌细胞的作用

目的 ：探讨腺病毒介导的肿瘤坏死因子相关凋亡诱导配体（TRAIL）基因对人胰腺癌株Panc-1细胞的抑制作用及其机制。方法 ：利用腺病毒载体Ad-TRAIL将人类TRAIL全长cDNA转染导入Panc-1细胞。分别利用RT-PCR和Western blot检测TRAIL在mRNA 水平及蛋白水平的表达。利用MTT法测定细胞增殖活性及TRAIL基因的旁观效应。利用流式细胞仪检测胰腺癌细胞的凋亡率，并用Western blot检测procaspase-8和procaspase-3蛋白的表达。结果 ：Panc-1细胞感染Ad-TRAIL腺病毒后，可稳定地高表达TRAIL。Ad-TRAIL能显著抑制Panc-1细胞的生长。高表达TRAIL的转染细胞能通过旁观效应导致未转染细胞的生长抑制。Ad-TRAIL实验组的凋亡率显著高于对照组（ P <0.01），且Ad-TRAIL能使procaspase-8和procaspase-3蛋白表达下降。结论 ：Ad-TRAIL对胰腺癌Panc-1细胞具有明显的抑制作用，其机制可能与促凋亡和旁观效应有关。

Antitumor effect of tumor necrosis factor-related apoptosis-inducing ligand gene transfection mediated by adenovirus in human pancreatic carcinoma cell

Objective To investigate the antitumor effect of tumor necrosis factor-related apoptosis-inducing ligand(TRAIL) gene transfection mediated by adenovirus into human pancreatic carcinoma cell line Panc-1,and the mechanisms involved in this effect.Methods TRAIL gene was transfected into pancreatic cancer cell line Panc-1 by an adenovirus vector(Ad-TRAIL).Level of TRAIL mRNA expression was determined using RT-PCR,and TRAIL protein synthesis was evaluated with Western blot.Cell-growth activities were determined by MTT assay.The bystander effect was observed by co-culturing the Panc-1 cells with and without the transfected TRAIL gene at different ratios.Apoptosis in pancreatic cancer cells was detected by flow cytometry.Proaspase-8 and procaspase-3 proteins were determined by Western blot.Results The stable overexpression of TRAIL was detected in Panc-1 cells transfected by Ad-TRAIL.Ad-TRAIL significantly inhibited cell viability of Panc-1 cells.Furthermore,co-culture of cancer cells transfected with TRAIL resulted in the nontransfected cell inhibition by bystander effect.Moreover,the percentage of apoptotic cells was significantly higher in the Ad-TRAIL-treatment group compared to the control groups(P<0.01),and there was a diminished amount of procaspase-8 and procaspase-3 after infection with Ad-TRAIL transfection.Conclusions The overexpression of TRAIL gene in Panc-1 cells by Ad-TRAIL exerts a marked antitumor effect,and the mechanisms involved in this effect may be related to proapoptosis and bystander effect.