miR-133过表达对结肠癌细胞SW480凋亡、增殖和裸鼠成瘤的影响

Effects of miR-133 overexpression on apoptosis,proliferation and tumor formation of colon cancer cells SW480 in nude mice

目的:探究miR-133过表达对结肠癌细胞SW480凋亡、增殖和裸鼠成瘤的影响。方法:将miR-133 mimic转染至SW480细胞,将细胞分为3组:对照组、Scramble组和miR-133 mimic组。RT-PCR检测miR-133表达水平;流式细胞仪检测细胞凋亡;Western印迹检测Bcl-2、Bax、Caspase-3、Caspase-9、c-Myc蛋白表达水平;CCK-8法检测细胞增殖倍数;克隆形成实验检测细胞克隆形成率;裸鼠右侧腋窝处皮下注射SW480细胞悬液建立裸鼠移植瘤模型,检测肿瘤重量,RT-PCR检测肿瘤组织miR-133表达水平,免疫组化检测Caspase-3、Ki67阳性细胞数。结果:与对照组相比,miR-133 mimic组miR-133表达升高(F=136.70,P<0.05),细胞凋亡率升高(F=59.995,P<0.05),Bax/Bcl-2、cleaved Caspase-3/Caspase-3、cleaved Caspase-9/Caspase-9表达升高(F=726.85、138.76、55.85,均P<0.05),c-Myc蛋白表达水平降低(F=88.98,P<0.05),细胞活力降低(F=48.50,P<0.05),克隆形成率降低(F=42.63,P<0.05),肿瘤重量降低(t=1.788,P<0.05),肿瘤组织miR-133表达水平升高(t=1.043,P<0.05),Caspase-3阳性细胞数升高(t=1.167,P<0.05),Ki67阳性细胞数降低(t=1.557,P<0.05)。结论:miR-133过表达诱导SW480细胞凋亡,抑制SW480细胞增殖和裸鼠肿瘤的形成。

Objective:To investigate the effects of miR-133 overexpression on the apoptosis,proliferation and tumor formation of colon cancer cells SW480 in nude mice.Methods:SW480 cells were transfected with miR-133 mimic.The cells were divided into three groups:control group,Scramble group and miR-133 mimic group.The expression of miR-133 was detected by RT-PCR.Flow cytometry was used to detect apoptosis.Western blotting was used to detect the expression of Bcl-2,Bax,Caspase-3,Caspase-9 and c-Myc.Cell proliferation was measured by CCK-8 method.The clone formation rate of cells was detected by clone formation experiment.The xenograft model of nude mice was established by subcutaneous injection of SW480 cell suspension in the right armpit,tumor weight was detected,the expression of miR-133 in tumor tissues was detected by RT-PCR,and the number of Caspase-3 and Ki67 positive cells were detected by immunohistochemistry.Results:Compared with control group,miR-133 mimic group showed increased expression of miR-133(F=136.70,P<0.05),increased apoptosis rate(F=59.995,P<0.05),increased Bax/Bcl-2,cleaved Caspase-3/Caspase-3,and cleaved Caspase-9/Caspase-9 expression(F=726.85,138.76,55.85,all P<0.05),and cell apoptosis rate(F=59.995,P<0.05),decreased C-Myc protein expression levels(F=88.98,P<0.05),decreased cell viability(F=48.50,P<0.05),decreased clone formation rate(F=42.63,P<0.05),reduced tumor weight(t=1.788,P<0.05),increased tumor tissue expression of miR-133 levels(t=1.043,P<0.05),increased Caspase-3 positive cells(t=1.167,P<0.05),reduced number of Ki67 positive cells(t=1.557,P<0.05).Conclusion:Overexpression of miR-133 induces apoptosis of SW480 cells and inhibits SW480 cells proliferation and tumor formation in nude mice.