缺氧诱导因子1α在肝癌细胞上皮-间充质化中的作用

目的:探讨缺氧诱导因子1 α(HIF-1 α)在肝癌上皮-间充质化(EMT)中的作用.方法:采用可调控HIF-1 α表达的肝癌HepG2Tet-on-HIF-1α细胞系,首先用real-time PCR与Western blot方法检测低氧环境中HepG2Tet-on-HIF-1α细胞EMT相关分子(E-cadherin,vimentin,FSP-1)及HIF-1 α的mRNA和蛋白表达水平,然后在常氧环境下,采用强力霉素(Dox)诱导HepG2Tet-on-HIF-1α细胞HIF-1 α过表达,以及HepG2Tet-on-HIF-1α细胞经Dox处理后再转染HIF-1αsiRNA,观察上述分子的表达情况.结果:低氧处理后,HepG2Tet-on-HIF-1α细胞EMT相关分子及HIF-1 α的mRNA和蛋白表达水平较常氧状态下均明显增加(均P＜0.05)；常氧环境下,Dox能诱导HepG2Tet-on-HIF-1α细胞HIF-1 α过表达,同时明显增加EMT相关分子的mRNA和蛋白表达水平(均P＜0.05),但转染HIF-1αsiRNA后,Dox的诱导作用被取消.结论:HIF-1α促进HepG2细胞EMT,并可能是肝癌基因治疗的有效靶点.

Function of hypoxia inducible factor 1α&alpha|in epithelial-mesenchymal transition of liver cancer cells

Objective: To investigate the role of hypoxia inducible factor 1α (HIF-1α) in epithelial-mesenchymal transition (EMT) process of hepatocellular carcinoma. Methods: HIF-1α inducible liver cancer cell line HepG2Tet-on-HIF-1α cells were used. First, the mRNA and protein expressions of EMT-related molecules (E-cadherin, vimentin and FSP-1) and HIF-1α in HepG2Tet-on-HIF-1α cells under hypoxia were determined by real-time PCR and Western blot analysis, respectively. Then, under normoxia condition, the expressions of above molecules were determined in HepG2Tet-on-HIF-1α cells with HIF-1α overexpression induced by doxycycline (Dox), and HepG2Tet-on-HIF-1α cells transfected with HIF-1α siRNA after Dox treatment. Results: After hypoxia treatment, the mRNA and protein expressions of EMT-related molecules and HIF-1α in HepG2Tet-on-HIF-1α cells were all significantly increased compared with normoxia status (all P<0.05). Under normoxia condition, HIF-1α was overexpressed, and the EMT-related molecules expressions were simultaneously increased significantly in HepG2Tet-on-HIF-1α by Dox exposure (all P<0.05), but the above effect of Dox was abolished by HIF-1α siRNA transfection. Conclusion: HIF-1α can promote EMT process in HepG2 cells, and probably may be an effective target for liver cancer gene therapy.