Since both EGFR and ERK5 are broadly expressed in various kinds of tissues, overexpression of TRAF4 in tumor cells leads to uncontrolled proliferation of tumor cells and development of NSCLC through setting up the EGFR‐TRAF4‐MEKK3‐ERK5 signaling axis. This evidence concerns the gene MAPK7 and non-small cell lung carcinoma.