Fig. 3. Inhibition of Src is required for the combined inhibitory effects of dasatinib and trametinib.

a Western blot analysis was performed on whole cell lysates from the 8505C cell line expressing either an empty vector (EV), wild-type Src (WT) or drug-resistant gatekeeper mutant Src (GK) treated with either DMSO, 100 nM trametinib, 100 nM dasatinib, or the combination for 24 h. Lysates were analyzed using the indicated antibodies. b The 8505C cell line expressing either an empty vector (EV), wild-type Src (WT) or drug-resistant GK mutant Src were treated with increasing doses of dasatinib ranging from (0.019 μM to 1.25 μM) for 72 h, in the presence of either DMSO or 100 nM trametinib. Cell growth was measured using the Sulforhodamine B assay. c Dasatinib IC₅₀ values were calculated using graphpad prism software in the presence or absence of 100 nM trametinib