In order to identify drugs to treat the two most common cancers lung and breast cancers, as well as overcome acquired resistance to targeted therapy, first, we searched the Gene Expression Omnibus (GEO) database for lung cancer or breast cancer vs. respective normal tissue, EGFR TKI-sensitive vs. acquired resistant lung cancer, and tamoxifen-sensitive vs. acquired resistant breast cancer. This evidence concerns the gene EGFR and lung cancer.