Fig. 3

Loss of PI3 kinase association increases the sensitivity of secondary mutations of KIT to Imatinib. a, b Ba/F3 cells stably expressing KIT mutants with or without PI3 kinase association were washed, starved and incubated with various concentrations of Imatinib and c, d Copanlisib (50 nM) for 4 h. After stimulation with 100 ng/ml SCF for 2 min and cell lysis, KIT activation was detected by probe KIT immunoprecipitates with pY antibody 4G10 and KitC1. pAkt, Akt and β-actin antibody were used to detect Akt activation in total cell lysates. Signal intensity was quantified and calculated to show the relative KIT activation