IC50 of inhibition of TEL-ABL and TEL-PDGFR kinases. BaF3 TEL-ABL (A) or BAF3 TEL-PDGFR (B) cells were incubated for 1.5 hours in the presence of the indicated concentration of inhibitor. Cells were lysed and equal amounts of lysate were analyzed by immunoblotting with antiphosphotyrosine (top panel of A and B) or anti-ABL or anti-PDGFR antibodies (bottom panel of A and B). Data were analyzed as for Fig 2. The data shown are representative of two separate experiments and similar values were obtained for the IC50s.