IL-6调节Twist的表达对肝癌细胞BEL-7402上皮-间质转化的影响

Influence of interleukin-6 on epithelial-mesenchymal transition through the regulation of Twist expression in human hepatoma cell line BEL-7402

目的探讨白细胞介素6(interleukin-6,IL-6)通过调节Twist的表达调控肝癌细胞上皮-间质转化(epithelial-mesenchy-mal transition,EMT)及侵袭转移的相关机制。方法用IL-6处理肝癌细胞BEL-7402,采用Transwell实验检测细胞迁移侵袭能力。采用Western blot和qRT-PCR技术检测低表达Twist对E-cadherin和vimentin蛋白表达水平的影响和mRNA表达的变化。结果 IL-6处理BEL-7402细胞后侵袭和迁移能力明显提高。相较于空白对照组(CON组)和RNA干扰阴性对照组(RNAi-NC组),在转染组RNAi-Twist细胞中,E-cadherin蛋白和mRNA的表达水平明显增加;vimentin的蛋白表达水平明显下调,而mRNA的表达水平差异无显著性。加入50 ng/ml IL-6孵育细胞24 h后,CON组和RNAi-NC组E-cadherin蛋白和mRNA表达均较未处理时明显减少,RNAi-Twist组减少的趋势不明显;vimentin蛋白表达均较未处理时明显升高,而RNAi-Twist组升高不明显,相应mRNA的表达水平差异均无显著性。结论 IL-6可提高肝癌细胞BEL-7402体外侵袭、迁移能力,促进EMT过程,其机制可能通过调节Twist的表达,从而诱导发生EMT和侵袭转移。

Purpose To investigate of the mechanism of interleukin-6 （IL-6） on epithelial-mesenchymal transition through the regula- tion of Twist expression in human hepatoma cell line BEL-7402. Methods Pretreatment with IL-6, cell migration and invasion were detected by transwell chamber assays. The influence of loss of Twist expression on the expression of E-eadherin and vimentin mRNAs and proteins was evaluated by quantitative reverse transcription polymerase chain reaction （qRT-PCR） and Western blot. Results By pretreatment with IL-6, the ability of cell migration and invasion was significantly increased. Compared to non-transfected BEL-7402 cells （control group） and those tranfected with RNAi-NC （RNAi negative control group）, the expression of E-cadherin mRNA and protein remarkably increased in BEL-7402 cells transfected with RNAi-Twist. Loss of Twist expression down-regulated vimentin protein expression, but had no significant impact on vimentin mRNA expression in BEL-7402 cells and those transfected with different siRNAs. After treated with IL-6 at a final concentration of 50 ng/ml for 24 h, the expression of E-cadherin mRNA and protein remarkably de- creased in non-transfected BEL-7402 cells and those tranfected with RNAi-NC and the decreasing trend was not significant in BEL-7402 cells transfected with RNAi-Twist. The expression of vimentin protein remarkably increased in non-transfected BEL-7402 cells and those tranfected with RNAi-NC and the increasing trend was not significant in BEL-7402 cells transfected with RNAi-Twist. The expres- sion of vimentin mRNA in BEL-7402 cells and those transfected with different siRNAs was not significantly different. Conclusion IL- 6 could promote the cell invasion, migration and epithelial-mesenchymal transition process of human hepatoma cells by regulation of Twist expression and the expression of EMT protein （ E-cadherin and vimentin）.