Figure 7

Mcl-1 depletion in JAK2 ^V617F mutant SET-2 cells increases apoptosis and sensitizes the cells to NVP-BSK805-induced cell death. A: Cell proliferation assays were carried out in SET-2 cells treated with increasing concentrations of NVP-BSK805 (empty triangles/solid line), obatoclax (filled squares/dotted line) or NVP-BSK805 in combination with a fixed obatoclax concentration of 700 nM (filled triangles/stippled line) for 72 hours. B: SET-2 cells were transfected with control (Ctrl) or Mcl-1 siRNAs. After 48 hours cells were treated with DMSO or 500 nM NVP-BSK805 for 24 hours. Then, DNA content was measured by FACS using propidium iodide (PI) staining. The x- and y-axes represent fluorescent channel 2-area (FL2-A) fluorescence intensity for PI staining and cell count, respectively. The percentage of cells in the respective cell cycle phases is indicated for each treatment condition. C: SET-2 cells were transfected with control (Ctrl) or Mcl-1 siRNAs. After 48 hours, cells were treated with 500 nM NVP-BSK805 or the drug vehicle DMSO for 24 hours and extracted for Western blot analysis. Arrowhead depicts cleaved PAPR running below the full-length PARP protein. β-tubulin was probed for as a loading control. D: SET-2 cells were transfected with control (Ctrl) or Mcl-1 siRNAs. After 24 hours cells were incubated for 48 hours with increasing concentrations of NVP-BSK805 to assess cell proliferation relative to the respective DMSO treated controls.