To test our hypothesis that osimertinib may decrease DR4 expression in EGFRm NSCLC cells due to its potent effect on suppressing the MEK/ERK signaling, we first determined the effect of osimertinib on DR4 expression in the two sensitive EGFRm NSCLC cell lines, PC-9 and HCC827. The gene discussed is MAP2K7; the disease is non-small cell lung carcinoma.