Representative Western blot.

These blots show (A) BCR-ABL expression and (B) DNA-PKcs expression and the effects of proteasome inhibition in CD34⁺ cells from a patient with CML and in CD34⁺ control cells from a patient with a neuroblastoma. Cells were grown in the presence of rhGM-CSF for 4 hours, with 2 μM lactacystin (lane 4) or 10 μM lactacystin (lanes 2 and 5) and without lactacystin (lanes 1 and 3). Using 10 μM lactacystin, it was possible to reverse the down-regulation of DNA-PKcs in the CD34⁺CML cells.