LATS1过表达对肺癌A549细胞增殖及周期的影响

通过过表达手段上调大肿瘤抑制因子1（1arge tumor suppressor gene 1，LATS1）基因在A549细胞中的表达，研究LATS1对A549细胞生长和细胞周期调控的作用。构建过表达LATS1基因的慢病毒载体，转染A549N胞株，采用RT-PCR和蛋白质印迹法检测转染后A549细胞中LATS1、YAPmRNA和蛋白的表达效率；流式细胞术检测细胞凋亡、周期情况：CCK-8检测细胞的增殖水平变化。结果发现，过表达LATS1慢病毒载体转染A549细胞株后，LATS1mRNA及蛋白表达水平高于未处理组及转染空载体组，YAPmRNA及蛋白表达水平低于未处理组及转染空载体组；过表达LATS1慢病毒转染后，A549细胞增殖率从第五天开始低于对照组（P〈0．05），过表达组细胞G1期比例明显增高（P〈0．05），凋亡率明显增加（P〈0．05），差异均有统计学意义。以上结果提示，LATS1可通过下调YAP的表达水平促进A549细胞的凋亡，诱导G1期阻滞，降低细胞的增殖能力。

Effect of LATS1 Over-Expression on Proliferation and Cell Cycle Regulation of A549 Cells

By over-expressing large tumor suppressor gene 1 （LATS1）, we aimed to investigate its effect on the proliferation and cell cycle regulation in lung cancer cell A549. LATS1 gene coding region was cloned into len- tivirus vector, and then lentivirus particles were transfected into A549 cells to up-regulate the expression of LATS1 gene. The expression of LATS1 and YAP were detected at both mRNA and protein levels by RT-PCR and Western blot. The apoptosis and cycle of cells were detected by flow cytometry. The proliferation level of cells was detected by CCK-8. The expression levels of LATS1 mRNA and protein were up-regulated significantly after the lentivirus vector of LATS1 over expression transfected into A549 cells. Meanwhile, the expression levels of YAP mRNA and protein were down-regulated. 5th days after transfection with lentivirus vector of LATS1 over expression, the pro- liferation rate of transfected cells was lower than untransfected cells （P〈0.05）. Flow cytometry showed that more cells of transfected went into phase G1 and fewer cells went into phase S. Moreover, apoptosis rate was significant increased in transfected cells （P〈0.05）. The results demonstrate that LATS 1 can promote A549 cells apoptosis, in- duce G1 phase arrest and inhibit the cell proliferation by down-regulating the expression of YAE