中文摘要：

目的应用RNA干扰技术抑制人舌癌细胞株Tca8113和SCC-4中Rho A基因的表达,探讨Rho A基因表达下调对舌癌细胞侵袭的影响。方法登录Genbank数据库确定人Rho A基因序列,针对Rho A的基因序列设计短链RNA,利用Lipofectamine2000介导法将Rho A-si RNA转染至舌癌Tca8113和SCC-4细胞。采用实时荧光定量聚合酶链反应检测转染后的舌癌细胞中Rho A m RNA的表达,蛋白质印迹法检测Rho A、半乳糖凝集素-3（galectin-3）和基质金属蛋白酶-9（MMP-9）蛋白的表达,Transwell小室检测细胞的侵袭能力。结果舌癌细胞转染Rho A-si RNA后,Rho A的基因和蛋白表达下降,galectin-3和MMP-9蛋白表达下降,细胞体外侵袭能力降低。结论 Rho A-si RNA可以有效地抑制舌癌Tca8113和SCC-4细胞中Rho A的表达,通过降低galectin-3和MMP-9的表达从而降低细胞的侵袭能力。Rho A在舌癌的侵袭和转移中可能发挥重要的作用。

英文摘要：

Objective To study the effects of Rho A down-regulation by RNA interference on the invasion of tongue carcinoma Tca8113 and SCC-4. Methods Determination of the human Rho A sequence as well as the design and construction of a short specific small interfering RNAs（si RNA） were performed. The si RNA of Rho A gene was transfected into human tongue squamous cell carcinoma Tca8113 and SCC-4 cells line by Lipofectamine 2000. Quantitative real-time polymerase chain reaction was used to examine the m RNA expression levels of Rho A. Protein expressions of m RNA, galectin-3, and matrix metalloproteinase（MMP）-9 were evaluated by Western blot. Transwell invasion assay was performed to assess the invasion ability of tongue carcinoma. Results Rho A expressions in Tca8113 and SCC-4 cells were reduced significantly after transfection of Rho A-si RNA. Protein levels of galectin-3 and MMP-9 were also down-regulated significantly. Invasion ability was inhibited as well. Conclusion Rho Asi RNA can effectively inhibit Rho A expression in Tca8113 and SCC-4 cells. The invasion ability of tongue carcinoma cells decreased with down-regulation of the protein expressions of galectin-3 and MMP-9, indicating that Rho A-si RNA can inhibit invasion of tongue carcinoma. Results show that Rho A may play an important role in the processes of invasion and metastasis of tongue carcinoma.