Figure 2.

Cells expressing ROS fusion kinases are sensitive to ALK inhibitors. A, ROS fusion kinases-expressing Rat1 cells were grown in the presence of NVP-TAE684 to determine IC₅₀ values. B, western blot analysis of total cell lysates from pooled Rat1 clones of ROS fusion kinases treated with NVP-TAE684 for 24 hours and probed for the indicated signaling proteins using phospho-specific antibodies. Blots were stripped and rehybridized with the indicated antibodies to control for expression levels and loading. (C–E) NVP-TAE684 reverses ROS fusion kinase-expressing Rat1 cells transformed phenotype. Cells were treated with NVP-TAE684 (10 nM) or vehicle and assayed for (C) saturation density growth inhibition, (D) focus formation and (E) growth in soft agar. Quantitation of the focus formation assay is depicted in Supplementary Fig. 4B.