EGFR and breast carcinoma: In line with our earlier findings with the breast carcinoma cell lines [17], LY294002 strongly downregulated NKG2D ligands, but PD98059 showed smaller effect than LY294002 on the expression of NKG2D ligands in both A549 (Fig 4E) and PC–9 cells (S4E Fig) suggesting that the EGFR signalling maintained the basal expression of NKG2D ligands via mainly PI3K-AKT pathway in both 2 cell lines.