肝细胞生长因子诱导人肝癌细胞上皮间质化

上皮间质转化（epithelial-mesenchymal transition，EMT）与肿瘤侵袭转移密切相关.虽然肝细胞生长因子（hepatocyte growth factor，HGF）已被证实为肿瘤EMT的主要诱导剂，但是HGF诱导肿瘤EMT发生的分子机制尚不完全清楚.本研究旨在探讨Snail在HGF诱导肝癌细胞上皮间质转化中的作用.用HGF处理肝癌HepG2和Hep3B细胞，显微镜观察细胞形态变化，划痕试验及Transwell试验检测细胞迁移能力，Western印迹检测Met，AKT的磷酸化及蛋白质表达的变化，Western印迹与real-time RT-PCR检测上皮细胞表面标志E-Cadherin和间质细胞表面标志N-Cadherin、Fibronectin的表达变化，以及EMT相关转录因子的表达变化.经HGF处理的HepG2、Hep3B细胞，Met和AKT的磷酸化水平显著增强；相差倒置显微镜下观察细胞形态向间质型细胞形态转化；细胞划痕和Transwell试验检测细胞的迁移能力较对照组显著增强；Real-time RT-PCR和Western印迹实验显示HGF的诱导能上调间质标记蛋白的表达及下调上皮型标志蛋白的表达.进一步发现，HGF能上调转录因子Snail的表达，干扰Snail能逆转HGF对HepG2和Hep 3B细胞EMT发生的诱导作用.由此可见，HGF可能通过诱导Snail的表达促进肝癌细胞EMT的发生.这为阐明肝癌细胞侵袭转移机制，以及肝癌的防治提供新线索.

Hepatocyte Growth Factor-induced Epithelial-mesenchymal Transition in Human Hepatocellular Carcinoma Cells

The epithelial-mesenchymal transition (EMT) is closely associated with the invasion and metastasis of tumors. Hepatocyte growth factor (HGF) can be a main inducer of tumor EMT, but the underlying mechanism is still not clear. In this study, we investigated the effect of Snail on HGF-induced EMT in HepG2 and Hep 3B hepatocellular carcinoma cells. The migration of HepG2 and Hep 3B cells were detected by wound healing and transwell assays. The proteins of p-Met, p-AKT, E-cadherin, Vmentin, Fibronectin, and Snail were determined by Western blotting. The mRNA expression of E-cadherin, vimentin, fibronectin, and Snail were determined by real-time RT-PCR. HGF induced HepG2 and Hep 3B underwent morphological changes from epithelial to mesenchymal appearance with increased migration behavior. HGF1 also up-regulated the expression of mesenchymal marker proteins and down-regulated the epithelial markers, with increased level of Snail expression. The EMT induced by HGF could be blocked by knocking down Snail. It suggested that Snail was involved in the invasion and metastasis of epatocellular carcinoma cells.