Effect of Akt/GSK-3β/Snail signaling pathway on EMT in A549/DDP cells mediated by TGF-β1 / 中国病理生理杂志

ABSTRACT

AIM:To observe the expression of Akt/GSK-3β/Snail signaling pathway-related molecules in cis-platin-resistant cell line A549/DDP mediated by transforming growth factor-β1 (TGF-β1), and to explore the association of Akt/GSK-3β/Snail signaling pathway with epithelial-mesenchymal transition (EMT). METHODS:The A549/DDP cells were divided into TGF-β1(+) group, TGF-β1(-) group and LY294002 group. The morphological changes of A549/DDP cells treated with TGF-β1 were observed under microscope. The protein expression of E-cadherin and N-cadherin was determined by the methods of immumofluorescence and Western blot. The protein levels of Akt, p-Akt, GSK-3β, p-GSK-3βSer9 and Snail were also detected by Western blot. RESULTS:The A549/DDP cells in TGF-β1(+) group were disper-sive, showed a spindle-like shape and developed pseudopodia. This transformation was conformed to classic EMT markers. Compared with TGF-β1(-) group, the protein expression of E-cadherin in TGF-β1(+) group was significantly decreased (P<0.05), and N-cadherin was significantly increased (P<0.05). The protein levels of p-Akt, p-GSK-3βSer9 and Snail were also significantly increased ( P<0.05). Compared with TGF-β1(+) group, the protein levels of p-Akt, p-GSK-3βSer9 and Snail were significantly decreased in LY294002 group (P<0.05). No difference of Akt and GSK-3β expression between TGF-β1(-) group and TGF-β1(+) group was observed. CONCLUSION:The mechanism of EMT in A549/DDP cells might be related to Akt/GSK-3β/Snail signaling pathway activated by TGF-β1.