Figure 1.

TNF-α and TGF-β1 combination induced A549 EMT in a reversible manner. (A) Pipeline of EMT induction and reversion (MET) in A549 cells. Cells were treated for 5 days with TNFα/TGF-β1 and then the cytokines were removed during the 5 next days (arrows) (B) Lung cancer cells A549 were observed on the fifth day of adherence with or without TNFα/TGF-β1 treatment under the microscope (40X magnification). To observe the cells undergoing MET (mesenchymal epithelial transition), the cytokines TNF-α and TGF-β1 were removed during the next 5 days. (C) Expression of epithelial marker E-CADHERIN and mesenchymal marker VIMENTIN in A549 after treatment with TNF-α and TGF-β1 were measured by Western-Blotting. One or two weeks after the removal of cytokines, expressions of E- CADHERIN and VIMENTIN were tested again. (D) EPCAM staining measured by FACS after treatment with TNF-α and TGF-β1, as well as, after the removal of cytokines during the next five days. The experiments in panels B, C and D were realized 4 times with similar results. (E) Representative staining of F-Actin using Rhodamine Phalloidin in A549 treated or not with TNF-α/TGF-β1. Nuclei were stained with DAPI. (F) The change in the invasive capacity of A549 with or without TNFα/TGF-β1 treatment was measured using Matrigel system. This experiment was performed in duplicate, and repeated 3 times (left: quantification; right: representative pictures).