CDK9在动脉粥样硬化组织中的表达及其敲低对血管平滑肌细胞增殖的影响  

EXPRESSION OF CDK9 IN ATHEROSCLEROTIC TISSUE AND EFFECT OF ITS KNOCKDOWN ON PROLIFERATION OF VASCULAR SMOOTH MUSCLE CELLS

作　　者：何兴强 陈作元[1] 田嘉伟[2] 李荣[1] 吕晓冰[1] 董蓓蓓 辛辉[1] HE Xingqiang;CHEN Zuoyuan;TIAN Jiawei;LI Rong;LYU Xiaobing;DONG Beibei;XIN Hui(Department of Cardiology, The Affiliated Hospital of Qingdao University, Qingdao 266003, China)

机构地区：[1]青岛大学附属医院心内科,山东青岛266003 [2]青岛大学附属医院急诊内科,山东青岛266003

出　　处：《精准医学杂志》2020年第3期222-225,229,共5页Journal of Precision Medicine

基　　金：青岛市民生科技计划项目(19-6-1-7-nsh)。

摘　　要：目的研究细胞周期蛋白依赖性激酶9(CDK9)在动脉粥样硬化(AS)组织中的表达,及其敲低对血管平滑肌细胞(VSMCs)增殖的影响及调控机制,并探讨其临床意义。方法收集我院健康体检者(A组)及冠心病患者(B组)外周血标本各20例,正常颈动脉内膜组织(C组)及颈动脉粥样硬化斑块组织(D组)各6例。选取VSMCs,分为阴性转染组(E组)和CDK9敲低组(F组),其中E组转染CDK9阴性对照(CDK9-NC),F组转染CDK9小干扰RNA(CDK9-siRNA)。通过实时荧光定量PCR(RT-qPCR)检测CDK9 mRNA在各组中的表达量以及E、F组中增殖细胞核抗原(PCNA)mRNA的表达量;采用Western blotting方法检测E、F组中CDK9、PCNA蛋白的表达量;通过EDU、CCK-8实验检测E、F组细胞的增殖情况。结果RT-qPCR检测结果显示,A组与B组、C组与D组中CDK9 mRNA的表达量比较,差异有显著性(t=7.94、4.79,P<0.05)。RT-qPCR和Western blotting检测结果显示,E组和F组中CDK9 mRNA和蛋白相对表达量比较,差异有显著性(t=30.33、16.39,P<0.05);E组和F组中PCNA mRNA和蛋白相对表达量比较,差异有显著性(t=8.14、12.62,P<0.05)。EDU和CCK-8实验结果显示,E组和F组平均吸光度值、波长450 nm处吸光度值比较,差异有显著性(t=13.13、6.78,P<0.05)。结论CDK9 mRNA在动脉粥样硬化组织中显著升高。在VSMCs中敲低CDK9可显著抑制细胞增殖及PCNA的表达。在AS中,CDK9可能通过影响PCNA的表达而调控VSMCs的增殖。Objective To investigate the expression of cyclin-dependent kinase 9(CDK9)in atherosclerotic tissue and the effect of its knockdown on the proliferation of vascular smooth muscle cells(VSMCs)and the regulatory mechanism,and to discuss its clinical significance.Methods Twenty peripheral blood samples each of healthy people on physical examination and patients with coronary heart disease were designated as group A and group B,respectively;six pieces of tissue each from normal carotid intima and carotid atherosclerotic plaque served as group C and group D,respectively;VSMCs were transfected with negative control siRNA(group E),or with CDK9-siRNA to knock down CDK9(group F).RT-qPCR was performed to determine the mRNA expression of CDK9 in each group and the mRNA expression of proliferating cell nuclear antigen(PCNA)in groups E and F.Western blotting was conducted to measure the protein expression of CDK9 and PCNA in groups E and F.EDU and CCK-8 assays were applied to determine cell proliferation in groups E and F.Results RT-qPCR showed that there were significant differences in the mRNA expression of CDK9 between group A and group B,and between group C and group D(t=7.94,4.79,P<0.05).The mRNA and protein expression of CDK9 and PCNA all exhibited significant differences between group E and group F(CDK9 mRNA and protein:t=30.33,16.39,P<0.05;PCNA mRNA and protein:t=8.14,12.62,P<0.05),according to RT-qPCR and Western blotting.The EDU and CCK-8 assays revealed that there were significant differences in mean absorbance value and the absorbance value at 450 nm between group E and group F(t=13.13,6.78,P<0.05).Conclusion The expression of CDK9 mRNA is up-regulated in atherosclerotic tissue.Knocking down CDK9 in VSMCs can significantly inhibit PCNA expression and cell proliferation.CDK9 may regulate the proliferation of VSMCs by affecting PCNA expression in atherosclerosis.

关 键 词：细胞周期蛋白依赖激酶9 肌细胞 平滑肌 肌 平滑 血管 细胞增殖 动脉粥样硬化 基因敲低技术 

分 类 号：R543.5[医药卫生—心血管疾病] R329.25[医药卫生—内科学]