转染肿瘤坏死因子相关凋亡诱导配体对膀胱癌细胞的抑制作用

目的探讨肿瘤坏死因子相关凋亡诱导配体（TRAIL）对膀胱癌细胞的抑制作用。方法构建TRAIL融合增强绿色荧光蛋白（EGFP）真核表达载体，脂质体法转染膀胱癌细胞株玎细胞。荧光显微镜下计算转染率。分别采用逆转录-聚合酶链反应（RT-PCR）、Western blot检测TRAIL的表达。采用流式细胞仪检测细胞凋亡，噻唑蓝（MTT）法、细胞倍增时间和集落形成率观察TRAIL的抑制作用。结果48h观察重组载体转染率为38．4％，空载体转染率为35．3％（P〉0．05）．RT-PCR和Western blot证实转染后EJ细胞中TRAIL的表达明显增加；凋亡率明显高于转染空白载体和未转染组（P〈0．01）；EJ细胞增殖受到明显抑制（P〈0．01）。结论TRAIL具有诱导膀胱癌细胞凋亡、抑制增殖的作用，有望成为治疗膀胱癌的新方法。

Inhibitory effects of tumor necrosis factor- related apoptosis-inducing ligand on human bladder carcinoma

Objective To investigate the inhibitory effects of tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) gene on the apoptosis and the growth of human bladder carcinoma cells. Methods The cDNA encoding full-length human TRAIL was cloned. The eukaryotic expression vector pEGFP-N1-TRAIL containing enhanced green fluorescent protein (EGFP) gene and expressing TRAIL was constructed, then transfected into EJ cells using a liposome-mediated transfection system. EGFP gene as a report gene was detected by fluorescent microscopy. TRAIL expression was detected by RT-PCR and Western blot. The apoptosis was determined by flow cytometry, and the cell growth inhibition were assessed by MTT, cell doubling generation time and colonyforming efficiency. Results Twenty-four h after transfection, fluorescence microscopy showed great number of EJ cells that expressed green fluorescence in both the pEGFP-N1 group and pEGFP-N1-TRAIL group. The rates of green fluorescent protein positive cells were 38.4% and 35.3% respectively in these two groups (P>0.05). RT-PCR and Western blot revealed TRAIL was increased significantly after transfection with TRAIL. A significantly higher rate of apoptosis was found in EJ cells transfected with TRAIL (P<0.01).The proliferation of the cells transfected with TRAIL was significantly decreased (P<0.01).Conclusion TRAIL may induce apoptosis and inhibit the proliferation of human bladder carcinoma cells, and may become a novel approach to treatment of cancer.