PTGS2 and non-small cell lung carcinoma: The hubs in the network with the highest numbers of links (≥ 10) included CD44, MET, IRS1, GRB10, ITGA2, PTGS2, and THBS1, all of which were highly expressed in EGFR-mutant NSCLC cells, indicating that some of the differentially expressed genes were at central positions of this signaling network.