Objective: To explore the role of SIRT1 in the occurrence of epithelial-mesenchymal transition (EMT) in EC-9706 and Eca-109 cells and the possible mechanism.
Methods: Three chemically synthesized siRNA targeting SIRT1 were transfected into EC-9706 and Eca-109 cells with the non-transfected cells and cells transfected with the negative siRNAs as controls. Real-time PCR and Western blotting were used to detect the expressions of SIRT1, E-cadherin, vimentin, Snail, Twist1 and ZEB in the cells. Transwell invasion assay and wounding healing assay were used to examine the changes in the invasion and metastasis abilities of the cells after transfection.
Results: EC-9706 and Eca-109 cells transfected with SIRT1 siRNA1 and SIRT1 siRNA3 showed significantly decreased mRNA and protein expressions of SIRT1 (P < 0.05). Transwell invasion assay and wounding healing assay showed that transfection with SIRT1 siRNA1 and SIRT1 siRNA3 caused significantly lowered invasion and metastasis abilities in EC-9706 and Eca-109 cells (P < 0.05). In EC-9706 and Eca-109 cells transfected with SIRT1 siRNA1 and SIRT1 siRNA3, the expression level of E-cadherin was significantly increased while the expressions of vimentin, Snail and Twist were significantly lowered (P < 0.05).
Conclusions: SIRT1 participates in the invasion and metastasis of EC-9706 and Eca- 109 cells probably by inducing EMT via regulating the expression of Snail.
目的: 探讨沉默信息调节因子1（SIRT1）诱导食管癌EC-9706和Eca-109细胞上皮间质转化（EMT）发生中的作用和机制。
方法: 转染3条化学合成SIRT1 siRNA入食管癌EC-9706和Eca-109细胞，以空白细胞和转染阴性对照siRNA细胞作为对照real-time PCR和western blot检测转染效果。Transwell侵袭小室和划痕实验检测各组细胞的侵袭转移能力变化。Real-time PCR和Western blot检测各组细胞上皮间质转化相关分子E-cadherin和vimentin的表达变化，同时进一步检测E-cadherin转录抑制因子Snail、twist1和ZEB的表达变化。
结果: 与空白组和阴性对照组细胞相比，转染SIRT1 siRNA1和SIRT1 siRNA3的EC-9706和Eca-109细胞SIRT1 mRNA和蛋白表达均明显降低，差异有统计学意义（P < 0.01）。Transwell侵袭小室和划痕实验结果显示转染SIRT1 siRNA1和SIRT1 siRNA3组EC-9706和Eca-109细胞穿膜细胞数和划痕愈合能力较空白组和阴性对照组细胞下降，差异有统计学意义（P < 0.05）。转染SIRT1 siRNA1和SIRT1 siRNA3组EC-9706和Eca-109细胞E-cadherin表达明显升高，而vimentin表达下降，与空白组和阴性对照组细胞相比差异有统计学意义（P < 0.05）。转染SIRT1 siRNA1和SIRT1 siRNA3组EC-9706细胞Snail表达下降，与空白组和阴性对照组细胞相比差异有统计学意义（P < 0.01）。转染SIRT1 siRNA1和SIRT1 siRNA3组Eca-109细胞Snail和twist1表达下降，与空白组和阴性对照组细胞相比差异有统计学意义（P < 0.01）。
结论: SIRT1有可能通过调控Snail表达诱导EMT发生从而在食管癌细胞侵袭转移中发挥作用。
Keywords: SIRT1; Snail; epithelial-mesenchymal transition; esophageal carcinoma; invasion and metastasis.