全反式维A酸联合c-myc RNA干扰抑制肺腺癌细胞增殖并诱导凋亡

目的 探讨全反式维A酸(ATRA)联合c-myc RNA干扰后肺腺癌细胞A549增殖和凋亡的改变及对survivin 基因表达的影响.方法 构建c-myc特异RNA小干扰(siRNA)的表达载体,转染A549细胞后G418(Geneticin)筛选出稳定表达c-myc特异siRNA的细胞株,荧光实时定量RT-PCR和免疫印迹 (Western blot)检测c-myc基因表达水平.ATRA作用于c-myc RNA干扰细胞,四甲基偶氮唑蓝(MTT)法检测吸光度值,流式细胞仪测凋亡率,定量RT-PCR和免疫印迹检测survivin基因表达.结果 成功构建c-myc-siRNA表达载体.c-myc基因mRNA和蛋白表达下降71.9%和85.6%.ATRA联合c-myc-siRNA细胞组吸光度值在各时间点较单用ATRA组,单用c-myc-siRNA组以及对照组均下降,差异有显著性(P＜0.01),凋亡率增加,差异有显著性(P＜0.01).ATRA联合c-myc-siRNA细胞, survivin表达下降49.2%,差异有显著性(P＜0.01).结论 ATRA联合c-myc-siRNA较单用ATRA或c-myc siRNA能更有效地抑制A549细胞的增殖,促进细胞的凋亡.survivin基因表达降低.

ATRA with c-myc RNA interference inhibits cell growth and induces apoptosis of lung adenocarcinoma

Objective To investigate the effects of all-trans retinoic acid(ATRA) with c-myc RNA interference on cell proliferation and apoptosis in lung adenocarcinoma cell.Methods The c-myc-siRNA expression vector was constructed and conformed by sequencing.This c-myc-siRNA expression vector was transfected into A549 cell and G418(geneticin)was used for selecting cell line which express c-myc-siRNA stably.The level of c-myc expression was tested by FQ RT-PCR and Western blot.This transfected cell was treated with ATRA.The cell proliferation and apoptosis were analyzed by MTT assay and flow cyclometry,survivin expression was tested by FQ RT-PCR and Western blot.Results C-myc-siRNA expression vector was constructed and transfected into A549 cell successfully,which could effectively reduce the c-myc mRNA and protein expression(71.9% and 85.6%,respectively).Cells treated with c-myc-siRNA and ATRA had a lower absorbance value at every time point than that of simple ATRA group,simple c-myc-siRNA group and control group(P<0.01).The apoptosis rate was also higher(P<0.01).In the course of apoptosis survivin expression was inhibited obviously.Conclusions The ATRA with c-myc-siRNA expression vector can effectively inhibit the proliferation and induce the apoptosis of lung adenocarcinoma A549.It can also effectively inhibit the expression of survivin gene.