沉默变异性浆细胞瘤异位1抑制鼻咽癌细胞增殖作用的机制研究  

The mechanisms of PVT1 downregulation on the cell proliferation of nasopharyngeal carcinoma

作　　者：万仁强[1] 翁泽平[2] 师小径[1] 裴娜娜 WAN Renqiang;WENG Zeping;SHI Xiaojing;PEI Nana(Department of Otolaryngology Head and Neck Surgery,Guangdong Second Provincial General Hospital,Guangzhou 510317,China;Department of Pathology,the First Affiliated Hospital of Jinan University,Guangzhou 510630,China)

机构地区：[1]广东省第二人民医院耳鼻咽喉头颈外科,广东广州510317 [2]暨南大学附属第一医院病理科,广东广州510630

出　　处：《中国耳鼻咽喉颅底外科杂志》2020年第5期485-490,共6页Chinese Journal of Otorhinolaryngology-skull Base Surgery

基　　金：国家自然科学基金青年科学基金项目(81702688);广东省医学科学技术研究基金项目(A2018351,A2017126);广东省第二人民医院青年基金(YQ2017-004)。

摘　　要：目的探讨变异性浆细胞瘤异位1(plasmacyto-mavarianttranslocation1,PVT1)抑制鼻咽癌细胞增殖的分子机制。方法构建特异性的shRNA PVT1慢病毒载体,包装慢病毒(LV/shRNA PVT1)并转导鼻咽癌C666-1细胞,检测Smad4的表达;LV/shRNA PVT1转导C666-1细胞24 h后转染Smad4 siRNA,通过细胞计数、四甲基偶氮唑蓝(MTT)法及流式细胞术分析沉默Smad4对LV/shRNA PVT1介导的鼻咽癌细胞生长及细胞周期的影响,并检测细胞周期相关调控因子的表达。结果下调PVT1后鼻咽癌细胞中Smad4的表达升高,而用siRNA沉默Smad4表达后,结果显示,抑制Smad4表达可阻断LV/shRNA PVT1介导的细胞生长抑制效应,同时细胞周期结果显示,与对照组相比,shRNA PVT1/Smad4 siRNA组细胞G1期比例降低,S期和G2期比例升高,并且CDK4、CDK6及c-myc的mRNA水平升高。结论下调PVT1可抑制鼻咽癌细胞增殖,并升高Smad4的表达,沉默Smad4可阻断shRNA PVT1对鼻咽癌细胞增殖的抑制效应;提示Smad4可能是PVT1作用的一个下游靶基因,下调PVT1可能通过Smad4抑制鼻咽癌细胞增殖。Objective To investigate the molecular mechanisms of plasmacytoma variant translocation 1(PVT1) downregulation on the cell proliferation of nasopharyngeal carcinoma(NPC).Methods Recombinant lentivirus that encoded PVT1 shRNA(LV/shRNA PVT1) was prepared. The NPC C666-1 cells were transduced with LV/shRNA PVT1 and then the expression of Smad4 was detected. Twenty-four hours after transduction, the C666-1 cells were transfected with Smad4 siRNA or control siRNA following the manufacturer’s protocol. And then cytometry, tetramethylazolazolam(MTT) method, and flow cytometry were adopted to detect the effects of silence of Smad4 on the cell growth and cell cycle of PVT1-induced C666-1 cells as well as the expressions of cell cycle regulators.Results The PVT1 expression was reduced while the Smad4 expression was increased after LV/shRNA PVT1 transduction. Transfection of Smad4 siRNA into C666-1 cells reduced the level of Smad4 expression and caused a significant blockage on the downregulation of PVT1-induced cell growth inhibition. Compared with the control cells, the number of S and G2-phase cells was significantly increased and that of G1-phase cells was reduced with significant increase in the expression of CDK4, CDK6 and c-myc in the PVT1-induced C666-1 cells.Conclusion Downregulation of PVT1 can inhibit the cell growth and increase the expression of Smad4. Silence of Smad4 may block the PVT1-induced cell growth inhibition. All these suggest that Smad4 maybe a downstream target gene of PVT1 and down-regulation of PVT1 expression may inhibit the cell growth via Smad4.

关 键 词：鼻咽癌 变异性浆细胞瘤异位1 SMAD4 细胞增殖 细胞周期 

分 类 号：R739.63[医药卫生—肿瘤]