We compared the expression levels of DHPS with responses to more than 297 drugs across 169 lung cancer cell lines (Supplementary Table 2); DHPS expression correlated negatively with cellular sensitivity to inhibitors of EGFR, BRAF, or MEK1/2 (Fig. 5b, c and Supplementary Fig. 3), indicating that high DHPS expression renders these cells and tumors more resistant to kinase inhibitors that target this pathway. Here, MAP2K1 is linked to lung cancer.