雷帕霉素靶向阻断作用对鼻咽癌细胞生长的实验研究

Inhibition of cell growth by rapamycin through targeting mammalian target of rapamycin signaling pathway in nasopharyngeal carcinoma

目的 研究雷帕霉素对鼻咽癌细胞株CNE-1、CNE-2的生长抑制作用及对细胞周期的影响.方法 采用活细胞计数试剂盒法（cellcounting kit-8,CCK-8法）观察不同浓度雷帕霉素在不同时间点对鼻咽癌细胞的生长抑制作用,光学显微镜下观察其形态学变化,流式细胞仪检测其细胞周期变化及细胞凋亡情况,反转录聚合酶链反应分析哺乳动物雷帕霉素靶蛋白基因的表达情况.结果 雷帕霉索在一定浓度范围内对鼻咽癌细胞株CNE-1、CNE-2的生长抑制作用随药物浓度的升高而逐渐增强.光镜下可观察到细胞变圆、密度降低等形态学的改变.流式细胞仪显示,150 nmol/L雷帕霉素作用48 h,CNE-1和CNE-2细胞生长周期均出现G0/G1期阻滞,且变化亦随药物浓度升高而增强;但诱导细胞凋亡作用不明显.反转录聚合酶链反应显示雷帕霉素使CNE-2细胞株哺乳动物雷帕霉素靶蛋白mRNA的表达下降（t=10.625,P＜0.01）.结论 雷帕霉素对鼻咽癌细胞株CNE-1、CNE-2具有生长抑制作用,可阻滞细胞周期进展,并可能通过下调哺乳动物雷帕霉素靶蛋白的表达而抑制细胞生长和细胞周期.

Objective To study the effects of rapamycin on cell growth and cell cycle in CNE-1 and CNE-2 cells. Methods Growth inhibition effect of rapamycin on CNE-1 and CNE-2 cells were assessed by cell counting kit-8 （CCK-8） assay. Morphological alterations of the cells were observed by microscope. Cell cycle and cell apoptosis were analyzed by FCM. The expression of mammalian target of rapamycin （mTOR）was analyzed by reverse transcription-polymerase chain reaction（RT-PCR）. Results The growth of CNE-1and CNE-2 cells was inhibited significantly by rapamycin dose-dependently. FCM showed that CNE-1 and CNE-2 cells at 48 hours after rapamycin （ 150 nmoL/L） treatment were arrested in the G0/G1 phase of cell cycle. However rapamycin treatment did not significantly induce apoptosis of CNE-1 and CNE-2 cells （P 〉0. 05）. RT-PCR showed that rapamycin significantly inhibited mRNA expression of mTOR in CNE-2 cells （t = 10. 625 ,P 〈 0. 01 ）. Conclusions Rapamycin inhibits the growth of CNE-1 and CNE-2 cells by inhibiting the progression of cell cycle, which could be achieved through decreaseing the expression of mTOR.