NDRG1 suppresses TGF-β-induced epithelial-mesenchymal transition in lung cancer A549 cells / 中国医师杂志

ABSTRACT

Objective To explore the effect and molecular mechanism of N-myc downstream regulated gene 1 (NDRG1) on transforming growth factor-beta (TGF-β)-induced epithelial-mesenchymal transition (EMT) in human lung cancer cells.Methods Lung cancer A549 cells were transfected with NDRG1 overexpressed vector,and then treated with 5 μg/L TGF-β1.The abilities of invasion were detected by Transwell assay.The expressions of NDRG1 mRNA and protein were analyzed by teal-time reverse transcription polymerase chain reaction (RT-PCR) were examined with Western blot.The expressions of EMT-associated markers E-cadherin and Vimentin,and EMT-associated signaling molecules Snail,AKT and Smad were detected with Western blot.Results We found that TGF-β1 treatment could induce morphological alteration of A549 cells from epithelial morphology to mesenchymal morphology.TGF-β1 significantly increased the migration of A549 cells,and increased the expression of mesenchymal maker vimentin and decreased epithelial marker E-cadherin.More importantly,overexpression of NDRG1 significandy reversed the effects of TGF-β1 on A549 cells.Moreover,NDRG1 significandy decreased the levels of phospho-AKT,and suppressed the expression of EMT-related transcription factor Snail.Conclusions NDRG1 could reverse the effects of TGF-β1 on EMT in A549 cells,by which mechanism is related to reduction of the expressions of phospho-AKT and Snail.