Cyclin E表达失调导致人类结肠癌染色体不稳定

Deregulation of Cyclin E induces chromosomal instability in human colon cancer

目的:研究Cyclin E的表达失调对人类结肠癌细胞系DLD1染色体稳定性的影响．方法:建立四环素调控的Cyclin E稳定表达的细胞系DLD1tTA—Cyclin E．Western blot检测Cyclin E表达．Cyclin E持续稳定表达1,3,5,7和14 d后,对细胞进行DAPI染色,在荧光显微镜下计数CIN细胞的百分比．结果:Western blot显示,Cyclin E表达在96 h后达最高峰．Cyclin E表达关闭的DLD1细胞中．CIN细胞的百分比波动在0．97％-1．22％之间(t =3．81,P>0．01);而Cyclin E持续表达1,3,5,7和14 d后的DLD1细胞中,CTN细胞的百分比分别为2．41％,3．63％,3．92％,6．17％和8．34％(t= 4．77,P<0．01)．结论:Cyclin E的表达失调可导致DLD1结肠癌细胞非整倍体数染色体的形成,也是造成结肠癌CIN的重要因素．

AIM： To study the influence of stably inducible expression of Cyclin E on the chromosomal instability in human colon cancer cell line DLD1.METHODS ： Tetracycline-responsive geneinducible cell line DLD1tTA-cyclin E was generated. Western blot was used to examine the induction of Cyclin E expression upon removal of doxycycline. 4＇-6-Diamidino-2-phenylindole （DAPI） staining was performed to detect the percentage of cells with chromosomal instability 1, 3, 5, 7 and 14 d after the induction of Cyclin E expression.RESULTS： Western blot showed that the peak of Cyclin E expression appeared 96 h after induction. The percentage of cells with chromosomal instability in tet-off DLD1tTA-Cyclin E cells ranged from 0.97% to 1.22% （t = 3.81, P 〉 0.01）. However, the percentages of cells with chromosomal instability were 2.41%, 3.63%, 3.92%, 6.17% and 8.34%, respectively, 1, 3, 5, 7 and 14 d after the induction of Cyclin E expression （t = 4.77, P 〈 0.01）.CONCLUSION： Deregulation of cyclin E can induce the formation of aneuploidy in human colon cancer cell line DLD1, and it also plays an important role in the pathway of chromosomal instability.