Fig. 3

Purinergic Receptor and TGF-β signaling in ATP-induced invasion in A549 cells. Effect of non-selective P2 purinergic antagonist (suramin and BAPTA) and P2X7 inhibitors (KN-62 and oATP), on A549 cell invasion. A549 cells were incubated with different inhibitors in the presence and absence of extracellular ATP for 20 h, and differential invasion rates were determined using Transwell assays. a, b Representative images and quantification of the invaded cells under suramin and BAPTA treatment. c, d Representative images and quantification of invaded cells under KN-62 and oATP treatment. e A549 cells were transfected with scrambled siRNA or P2X7 siRNA and incubated for 48 h. The expression of P2X7 was detected by Western blot. f 48 h after transfection, ATP-induced cell invasion was examined using a Transwell Assay. g Relative effects of ATP and TGF-β on cell migration. h Relative effects of ATP and TGF-β on cell invasion. Experiments were performed in triplicate and data are presented as the mean ± standard deviation. *P < 0.05, **P < 0.01 and ***P < 0.001