A, U251-MG cells were treated with 1 μM JSI-124 for the indicated times, lysed and immunoblotted with the indicated Ab. B, U251-MG cells were pretreated with various concentrations of JSI-124 for 2 h, followed by treatment with 1 ng/ml OSM for 15 min. Cells were lysed and immunoblotted with the indicated Ab. C, U251-MG cells were plated in 96 well plates and incubated with various concentrations of JSI-124 or vehicle control (DMSO) for the indicated times, and the WST-1 cell proliferation assay was performed. Data represent mean ± SD, replicates of three. Beginning at 24 h, the 0.1 μM, 1 μM and 10 μM concentrations of JSI-124 reached statistical significance (*, p<0.005; ANOVA). D, Cytotoxic drug dose response curve of U251-MG cells with a 24 h treatment with JSI-124. E, U251-MG cells were treated with various concentrations of JSI-124 for 24 h, lysed and immunoblotted with the indicated Ab.