Abstract:

Objective To study the effects of RhoA down-regulation by RNA interference on the invasion of tongue carcinoma Tca8113 and SCC-4. Methods Determination of the human RhoA sequence as well as the design and construction of a short specific small interfering RNAs (siRNA) were performed. The siRNA of RhoA 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 mRNA expression levels of RhoA. Protein expressions of mRNA, 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 RhoA expressions in Tca8113 and SCC-4 cells were reduced significantly after transfection of RhoA-siRNA. Protein levels of galectin-3 and MMP-9 were also down-regulated significantly. Invasion ability was inhibited as well. Conclusion RhoA-siRNA can effectively inhibit RhoA 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 RhoA-siRNA can inhibit invasion of tongue carcinoma. Results show that RhoA may play an important role in the processes of invasion and metastasis of tongue carcinoma.

Key words: RhoA gene, galectin-3, matrix metalloproteinase-9, RNA interference, tongue carcinoma, invasion