中文摘要：

为研究鼻咽癌相关新基因NPCEDRG的功能,探讨其对鼻咽癌细胞生长特性的影响,利用Tet-on调控系统,建立受强力霉素（deoxycycline,Dox）诱导NPCEDRG基因表达的CNE2细胞系.运用RT-PCR选择背景表达低、诱导活性高的细胞克隆,以不同浓度Dox诱导CNE2/Tet/TRE-NPCEDRG细胞,确定Dox的最佳诱导浓度.借助形态学观察、细胞生长曲线、软琼脂克隆形成试验和流式细胞仪分析等方法,对Dox诱导NPCEDRG高表达后CNE2细胞的生物学行为进行了检测.结果显示,NPCEDRG高表达后CNE2细胞增殖速度显著减慢（P〈0.05）,克隆形成能力显著降低（P〈0.01）,瘤细胞群体中处于G0/G1期细胞数增加,S期细胞数减少,细胞阻滞于G0/G1期.Tet调控NPCEDRG基因表达CNE2细胞系成功建立,恢复NPCEDRG表达能部分逆转CNE2的恶性表型,证明NPCEDRG是一个鼻咽癌相关的抑瘤基因.

英文摘要：

To investigate the inhibitory function of NPCEDRG,a novel tumor suppressor gene,in nasopharyngeal carcinoma（NPC）,Tet-on system was introduced.Two plasmids were co-transfected into CNE2 cells,then a transgene CNE2 cell line,which had rapidly inducible and reversible expression of NPCEDRG,was obtained after two selections with G418 or hygromycin.NPCEDRG mRNA expression was detected via RT-PCR assay.Dox was used to induce the expression of NPCEDRG and a cell clone sensitive to Dox was selected.The best-induced concentration was determined with different concentration of Dox induction.Cell morphology observation,growth curves,clone formation rate and cell cycle distribution were detected after NPCEDRG restoration expression with Dox induction.After the restoration of NPCEDRG expression,the degree of CNE2 differentiation was higher than ever,the growth capacity and clone formation potential of CNE2 cells in soft agar were significantly suppressed,and the cell percentage in G0/G1 phase increased,while percentage of cells entering the S and G2 phase decreased.This data indicates that an abnormality of NPCEDRG expression is associated with nasopharyngeal carcinogenesis and that it may play an important role in inducing cell differentiation,controlling cell growth and regulating the cell cycle.