特异性干扰TACC3基因表达对CD133^+CD44^+口腔鳞癌干细胞增殖及凋亡的影响

Effects of specific interfering TACC3 gene expression on proliferation and apoptosis of CD133^+CD44^+ oral squamous cell carcinoma cells

背景:研究表明,TACC3基因在多种肿瘤中均表达上调,因此体外特异性干预TACC3的表达,可能是治疗或干预肿瘤生长的重要靶点。目的:探讨沉默TACC3基因表达对口腔鳞癌干细胞增殖和凋亡的影响。方法:采用免疫磁珠分选技术从人口腔鳞癌细胞Cal-27中分选出CD133^+CD44^+口腔鳞癌干细胞。shRNA转染组设计及合成TACC3 shRNA序列,利用Lipofectamine^(TM)2000将TACC3 shRNA序列转染至CD133^+CD44^+口腔鳞癌干细胞,设置空载体转染阴性对照组和未转染组。转染48 h后,采用MTT、细胞克隆形成实验、TUNEL凋亡实验检测沉默TACC3基因对体外CD133^+CD44^+口腔鳞癌干细胞增殖、凋亡的影响;Western blot检测沉默TACC3基因对CD133^+CD44^+口腔鳞癌干细胞Ki67、Bax、Bcl-2蛋白表达的影响。结果与结论:(1)细胞增殖:shR NA转染组细胞增殖速度、增殖相关蛋白Ki67表达水平明显低于阴性对照组和未转染组(P<0.05);(2)细胞克隆形成能力:shRNA转染组细胞克隆形成能力显著低于阴性对照组和未转染组(P<0.05);(3)细胞凋亡:shRNA转染组细胞凋亡高于阴性对照组和未转染组,促凋亡蛋白Bax水平高于未转染组、对照组,抗凋亡蛋白Bcl-2表达低于阴性对照组和未转染组;(4)结果表明:干扰抑制TACC3基因表达,可抑制口腔鳞癌干细胞的增殖,促进其凋亡。

BACKGROUND:Studies have indicated that the abnormal expression of TACC3is closely related to the occurrence and development of many kinds of tumors,and the expression of TACC3is up-regulated in these tumors.Therefore,in vitro specific inhibition of TACC3expression may become an important target for the treatment or intervention of tumor growth.OBJECTIVE:To investigate the mechanism by which TACC3gene expression regulates cell proliferation and apoptosis in oral squamous cell carcinoma.METHODS:CD133+CD44+oral squamous cell carcinoma cells were sorted from human oral squamous cell carcinoma cell line Cal-27by immunomagnetic beads.In experimental group,the shRNA sequence of TACC3was designed andsynthesized,which was then trasnfected into CD133+CD44+oral cancer stem cells by LipofectamineTM2000.Empty vector-trasnfected(negative control)and untransfected cells were used as callsed.Forty-eight hours after the transfection,effects of TACC3gene silencing on proliferation and apoptosis in vitro in CD133+CD44+oral squamous cell carcinoma were detected by MTT,clone formation test,and TUNEL assay.Western blot assay was used to detect the effect of TACC3gene silencing on Ki67,Bax and Bcl-2protein expression in CD133+CD44+oral squamous cell carcinoma.RESULTS AND CONCLUSION:(1)Cell proliferation.The proliferation rate and expression level of Ki67were significantly lower in the experimental group than the negative control and untransfected groups(P<0.05).(2)Clone formation.The clone formation ability in the experimental group was significantly lower than that in the negative control and untransfected groups(P<0.05).(3)Cell apoptosis.TACC3gene silencing caused an obvious decrease in Bcl-2protein expression and a significant increase in Bax protein expression.These findings further confirmed that specific interference of TACC3gene expression could inhibit the proliferation of CD133+CD44+cells and promote the apoptosis.