RNA干扰沉默CXCR4基因对Jurkat细胞周期和凋亡的影响

本文研究探讨下调CXCR4的表达对人T-ALL Jurkat细胞周期和凋亡的影响。设计合成CXCR4的特异性siRNA，采用脂质体转染Jurkat细胞株。用RT—PCR检测siRNA对细胞内CXCR4基因表达的影响，用流式细胞术检测细胞周期分布和细胞的凋亡情况。结果表明：成功构建了CXCR4的特异性siRNA；与空白对照组相比，转染CXCR4siRNA的Jurkat细胞的CXCR4mRNA表达水平明显下降（56．9％±1．4％FS68．3％±2．4％），G0／G1期细胞比例增加（35．8％±1．9％vs18．1％±1．2％），G，／M期和S期细胞比例相应下降（19．8％±1．7％VS27．2％±1．5％；44．4％±2．1％VS54．7％±2．8％），凋亡细胞率明显增高（20．9％±2．0％VS3．13％±0．9％）。结论：CXCR4的特异性siRNA能够有效下调CXCR4基因表达，诱导Jurkat细胞凋亡和细胞周期阻滞，从而抑制细胞的增殖。

Effects of CXCR4 Silence Induced by RNA Interference on Cell Cycle Distribution and Apoptosis of Jurkat Cells

This study was aimed to investigate the effect of down-regulating the CXCR4 expression on cell cycle and cell apoptosis of human T-ALL Jurkat cells. The CXCR4 specific siRNA plasmid vector was constructed and then transfected into the cultrued Jurkat cell line by DMRIE-C. The expression of CXCR4 mRNA was detected by RT-PCR, the cell distribution in cell cycle and cell apoptosis were determined by flow cytometry. The experiments were divided into 3 groups： group A （blank control）, group B （ non-silencing dsRNA as negative control ） and group C （ CXCR4 siRNA）. The results showed that the expression level of CXCR4 mRNA in Jurkat cells transfected with CXCR4 siRNA （ group C） decreased and cell proportion in G0/G1 phase increased as compared with group A （ 56.9% ± 1.4% vs 68. 3 % ± 2.4% and 35.8% ± 1.9% vs 18.1% ± 1.2% respectively） （p 〈 0.01 ）, cell proportion in G2/M and S phase decreased as compared with group A （19. 8% ± 1.7%, 44.4% ±2. 1% vs 27. 2% ± 1.5%, 54. 7% ±2. 8% respectively） （p 〈0.01 ）. The apoptosis rate of Jurkat cells in group C increased as compared with group A （20.9% ± 2.0% vs 3.13% vs 0.9% respectively） （p 〈0.01） , and the comparison between group A and B showed no statistical difference. It is concluded that the CXCR4 specific siRNA can effectively down-regulate the CXCR4 mRNA expression, which induces the cell apoptosis and cell cycle arrest, thereby inhibits the Jurkat cell proliferation.