Coexpression of Lyn and Syk induced nilotinib resistance in Ks cells. Ks cells were transfected with Lyn and Syk constructs with a ratio of 4:1 to mimic the over expression of Lyn in K-rn cells. Both Lyn wild type (Lyn wt panel A) and the constitutively activated Lyn (Lyn Y508 panel B) were used in combination with Syk wild type (wt), constitutively activated (Y130) and kinase dead (K402). On day 1 at the time of transfection nilotinib was added (indicated by the arrow, 20nM) and cell proliferation was quantified over a 4 days time course experiment by triplicate cell counting. Results are from 1 experiment representative of 2. (C) Samples taken at day 4 and analyzed for Lyn and Syk expression.