RAC1对人舌鳞癌CAL27细胞迁移、侵袭的影响

目的: 构建RAC1基因小干扰RNA（small interfering RNA,siRNA）,探讨RAC1对人舌鳞癌CAL27细胞侵袭、迁移的影响及其分子机制。 方法: 针对人RAC1基因设计并合成3条siRNA,通过脂质体介导转染进3组人舌鳞癌细胞CAL27中,以抑制RAC1的表达;同时设置阴性对照组（转染无关核苷酸序列）和空白对照组（未转染）,采用实时荧光定量PCR检测细胞中RAC1 mRNA的表达, Western 免疫印迹实验检测RAC1、PAK1、LIMK1蛋白的表达,通过划痕实验及Transwell细胞侵袭实验检测转染后细胞迁移和侵袭能力的变化。采用SPSS 18.0软件包对数据进行统计学分析。 结果: 细胞转染48 h后,与阴性对照组和空白对照组相比,RAC1干扰组细胞RAC1 mRNA和蛋白表达均显著下降（P<0.05）,PAK1、LIMK1蛋白表达显著下降（P<0.05）,细胞迁移和侵袭能力显著降低（P<0.05）。 结论: 沉默RAC1基因可抑制舌鳞癌CAL27细胞的侵袭和转移,其机制可能与细胞内PAK1、LIMK1的表达下调有关。

Effect of RAC1 on migration and invasion of human squamous cell carcinoma of tongue cell line of CAL27

PURPOSE: To investigate the effect of RAC1 on invasion and migration of human squamous cell carcinoma of tongue cells of CAL27, as well as the possible molecular mechanism. METHODS: The specific small interfering RNAs (siRNAs) was designed and constructed on the basis of RAC1 gene sequence. Through liposome mediation, these three RAC1 siRNAs were transfected into CAL27 cells to inhibit RAC1 expression. Meanwhile, negative control group and blank control group were transfected with random sequence NC-siRNA and liposome, respectively. The mRNA of RAC1 were detected by real-time fluorescence quantitative polymerase chain reaction and the protein expression of RAC1, PAK1, LIMK1 were examined by Western blotting. The migration and invasion ability were analyzed by wound healing assay and Transwell chamber test. One-Way ANOVA and student's t test were used for data analysis with SPSS 18.0 software package. RESULTS: The protein expression of RAC1 was decreased significantly 48h after transfection (P<0.05), the expression of PAK1 and LIMK1 were suppressed (P<0.05), the migration and invasion ability of CAL27 cells was also significantly inhibited (P<0.05). CONCLUSIONS: Silencing RAC1 gene can inhibit migration and invasion ability of human squamous cell carcinoma of tongue CAL27 cells, and the mechanism may be related to down-regulation of PAK1 and LIMK1 expression in tongue cancer cells.