To define cell lines that are responsive to combined Src and MEK1/2 inhibition, we chose 90 nM as the IC50 cutoff for dasatinib based on the selectivity of dasatinib and the peak/plasma concentration in chronic myelogenous leukemia patients [19]. The gene discussed is MAP2K1; the disease is chronic myelogenous leukemia, BCR-ABL1 positive.