EGFR and brain cancer: We found that co-resistance between gefitinib and AMDs (i.e., gefitinib ↔ paclitaxel or gefitinib ↔ epothilone B) can serve as a proxy to represent co-resistance between all EGFR-TKIs and AMDs, at least based on the similar co-resistance frequencies in lung, breast, and brain cancers (Fig. 1c).