LMP1瞬时过表达对鼻咽癌CNE2细胞迁移的影响

The effect of transient over-expression of LMP1 on the migration of human nasopharyngeal carcinoma CNE2 cells

目的 :探讨潜伏膜蛋白1(latent membrane protein 1,LMP1)瞬时过表达对鼻咽癌CNE2细胞迁移的影响及其可能的作用机制。方法 :成功构建重组真核表达载体pEGFP-C1-LMP1,并将其瞬时转染至CNE2细胞,激光共聚焦显微镜下观察LMP1在CNE2细胞中的定位,Transwell法检测LMP1对CNE2细胞迁移和侵袭能力的影响,实时荧光定量PCR和蛋白质印迹法检测LMP1和Ras相关C3肉毒素底物1(Ras-related C3 botulinum toxin substrate 1,Rac1)mRNA及蛋白的表达。结果 :pEGFP-C1-LMP1成功转染至CNE2细胞后,可见LMP1主要表达于细胞膜和部分细胞质中,CNE2细胞的侵袭和迁移能力明显低于转染空载体的对照组(P<0.05),CNE2细胞中LMP1 mRNA及蛋白的表达水平明显高于转染空载体的对照组(P<0.01),而Rac1 mRNA及蛋白的表达水平明显低于转染空载体的对照组(P<0.05)。结论 :LMP1瞬时过表达可抑制鼻咽癌CNE2细胞的迁移,这一作用可能与Rac1表达下调有关。

Objective： To investigate the effect of transient over-expression of latent membrane protein 1 （LMP1） on the migration of human nasopharyngeal carcinoma CNE2 cells and its possible mechanism. Methods： The recombination eukaryotic expression plasmid pEGFP-C1-LMP1 was successfully constructed, and it was transiently transfected into nasopharyngeal carcinoma CNE2 cells. After pEGFP- C1-LMP1 was transfected into CNE2 cells, the location of LMP1 was observed under a laser confocal microscope, and the abilities of migration and invasion of CNE2 cells were analyzed by Transwell assay, then the expression levels of LMP1 and Ras-related C3 botulinum toxin substrate 1 （Racl） mRNAs and proteins were examined by real-time fluorescence quantitative-PCR and Western blotting, respectively. Results： After pEGFP-C1-LMP1 was successfully transfected into CNE2 cells, LMP1 could be obtained mainly in cell membrane and part of the cytoplasm of CNE2 cells. The capacities of migration and invasion of CNE2 cells transfected with pEGFP-C1-LMP1 were weaker than those of the CNE2 cells transfected with empty vector （as a control） （P 〈 0.05）. The expression levels of LMP1 mRNA and protein in CNE2 cells transfected with pEGFP-C1-LMP1 were higher than those of the control （P 〈 0.01）, whereas the expression levels of Racl mRNA and protein were just the opposite （P 〈 0.05）. Conclusion： The transient over-expression of LMP1 can inhibit the migration of nasopharyngeal carcinoma CNE2 cells. This effect may be related to the down-regulation of Racl expression.