Fig. 4

Effect of P2R antagonist on EGFR ligand release and expression in poly(I:C)-treated NCI-H292 cells. a-d Effect of a non-selective antagonist of P2R, suramin on the release and expression of EGFR ligands (amphiregulin and TGF-α). A 10 micromolar concentration of suramin was added 30 min before 10 μg/ml poly(I:C) treatment. After 24 h, whole cells and supernatants were harvested and assayed for the release of amphiregulin and TGF-α by ELISA and the expression of amphiregulin and TGF-α gene by Real-time PCR. e, f Effect of P2Y2R silencing with siRNA on the release of amphiregulin and TGF-α on poly(I:C)-treated cells. Cells were treated with P2Y2R silencing by siRNA prior to the treatment with 10 μg/ml poly(I:C). After 24 h, the supernatants were harvested and assayed for the release of amphiregulin and TGF-α. The data are expressed as the means ± SEM for three to four separate experiments. P2Y2R siRNA(-) siRNA denotes non-targeting siRNA treatment. **p < 0.01, ***p < 0.001 compared with the values of vehicle-treated control. ⁺⁺⁺ p < 0.001 compared with the values of suramin or siRNA-treated control