Frequency of resistant clones decreases with increasing nilotinib concentrations. Ba/F3 Mig EGFP Bcr-Abl p185 wild-type cells were cultured in 96-well plates in the presence of nilotinib at the indicated concentrations. Resistant colonies were picked and analyzed for the presence of point mutations within the Bcr-Abl kinase domain. Wild-type (□) and mutant (▪) sublines are shown separately. The frequency is shown as resistant clones per million cells at the beginning of culture.