TGF-β1基因转染对人晶状体上皮细胞周期调控的影响

Effect of TGF-β1 gene transfection on the cell cycle control of human lens epithelial cell

目的:探讨脂质体介导的TGF-β1基因(pEGFP-TGF-β1)转染诱导人晶状体上皮细胞系-B3(HLEC-B3)细胞周期蛋白激酶抑制因子p21及细胞周期蛋白激酶CDK2的表达及其对细胞周期调控的影响。方法:将pEGFP-TGF-β1转染人晶状体上皮细胞系-B3(HLEC-B3),采用RT-PCR和Western-blot方法检测pEGFP-TGF-β1转染后24,48,72,96hp21,CDK2和Smad4mRNA和蛋白的表达,设立正常细胞组及pEGFP-C2转染组为对照组。结果:pEGFP-TGF-β1转染组TGF-β124h开始升高,48h达到最高,72h略有减少,96h明显减少,但仍高于正常组,而空载体组与正常细胞组则无明显变化。p21变化趋势和TGF-β1相符,CDK2组变化趋势则正好相反,Smad4组48h明显升高,72h下降明显,96h基本恢复正常。结论:TGF-β1通过活化凋亡基因p21,降低细胞周期蛋白激酶CDK2。

AIM： To investigate the change of p21 ,CDK2 and Smad4 on the HLEC transfected with pEGFP-TGF-β1 plasmid and the effect of TGF-β1 gene transfection on the cell cycle control of human lens epithelial cell. METHODS. Immortalized human lens epithelial cellline （HLEC-B3） was transfered by pEGFP-TGF-β1 gene. The expression of TGF-β1mRNA, p21mRNA, CDK2mRNA and Smad4 mRNA and protein induced by transfered by TGF- β1 gene were measured by RT-PCR and Western- blot at different time periods. RESULTS： RT-PCR detected that TGF-β1 mRNA began to raise after 24h, culminated after 48h ,decreased after 72h, decreased much after 96h,but still more than the normal. p21mRNA companied with it. but CDK2 decreased with it. Western-blot detected that the consequence consisted with RT-PCR. The effect of TGF-β1 gene was demonstrated from the lever of transcription and translation. Smad4 protein raised with the lever of TGF-β1 gene at various time point, but disappeared very quickly. CONCLUSION： TGF-β1 can increase p21, but decrease CDK2, to impact the cell cycle of HLEC. TGF-β/Smad4 pathway take part in the course.