2-DG增强TRAIL诱导鼻咽癌细胞凋亡的敏感性作用

2-DG sensitizes nasopharyngeal carcinoma cells to TRAIL induced apoptosis

目的探讨糖基化抑制剂2-脱氧葡萄糖(2-deoxy-D-glucose,2-DG)对肿瘤坏死因子相关凋亡诱导配体(tumorsnecrosis factor-related apotosis-inducing ligand,TRAIL)诱导肿瘤细胞凋亡作用的影响,以期为鼻咽癌的治疗提供新的靶点。方法 MTT法检测不同浓度(0、0.625、1.25、2.5、5、10mmol·L-1)2-DG以及不同浓度2-DG与TRAIL(200μg·L-1)合用对鼻咽癌细胞CNE-2的增殖抑制作用。溴化丙啶(propidium iodide,PI)单染检测2-DG(5 mmol·L-1)对TRAIL诱导鼻咽癌细胞CNE-2凋亡的影响;Western blot检测2-DG(5 mmol·L-1)处理鼻咽癌细胞CNE-2不同时间(0、6、16、24 h)葡萄糖调节蛋白(glucose-regulated protein 78,GRP-78)以及联合TRAIL处理后Caspase-3的表达;实验中检测了2-DG及TRAIL合用对集落克隆形成的影响。结果 5 mmol·L-12-DG作用于鼻咽癌细胞CNE-2 24、48、72 h细胞存活率分别为76.96%、70.83%、69.39%,而诱导CNE-224 h细胞凋亡率仅为7.7%。5 mmol·L-12-DG与TRAIL联合作用于鼻咽癌细胞CNE-2 24 h的凋亡率为78.9%,高于TRAIL单用诱导凋亡率38.2%,并且2-DG可增强TRAIL抑制鼻咽癌细胞CNE-2的集落克隆形成的作用。2-DG能上调GRP-78的活性并且增强Caspase-3的激活。结论 2-DG能增强TRAIL诱导鼻咽癌细胞的凋亡,其机制可能通过引起过度的内质网应激反应以及增强Caspase-3的激活。

Aim To determine whether 2-DG （2-deoxy-D-glucose） can synergize with tumors necrosis fac- tor-related apotosis-inducing ligand （TRAIL） which is used in nasopharyngeal carcinoma treatment and wish to find new targets for human nasopharyngeal carcinoma chemotherapy. Methods Nasopharyngeal carcinoma cells CNE-2 were incubated with varying concentrations of 2-DG （0, 0.625, 1.25, 2.5, 5, 10 mmol · L-1） with or without TRAIL （200 μg · L- l ）. Cell viability was measured by the MTF （3-（4, 5-dimethylthiazol-2- yl ） -2-5 diphenyltetrazolium bromide ） assay. Then propidium iodide （PI） staining was used to measure ap- optotic cells in Flow Cytometry （FCM）. CNE-2 cells were treated with 2-DG （5 mmol· L-1） （with or without TRAIL） for different time points （0, 6, 16, 24 h）. Western blot was used to measure the protein expression of glucose-regulated protein 78 （ GRP-78 ） and Caspase-3. Results Combining 2-DG with TRAIL resulted in enhanced cell death compared with the individual use of each agent, 2-DG induced apoptosis cells hardly reached 10% and 2-DG markedly up-regulated GRP-78 and Caspase-3 expression. With the combination of 2-DG and TRAIL, the apoptotic rate of CNE-2 cells reached 78.9%. Conclusion These results indicate that 2-DG sensitizes nasopharyngeal carcinoma cells to TRAIL induced apoptosis by up-regulation of GRP-78 and Caspase-3.