MYC protein levels in PML-RARα + MYC or MYC mutant leukemias. (A) Whole-cell lysates from normal bone marrow (Cntr) and PML-RARα + MYC, MYCT58A, or MYCΔMBII leukemic cells were probed with anti-MYC. The same blot was stripped and reprobed with anti–β-actin antibody for loading control. Cell lysates of FDC-P1 cells and FDC-P1 transduced with MYC are also shown. (B) Optical density of MYC protein was normalized to β-actin and shown as the percentage of MYC level in normal bone marrow (Cntr). Means ± SD are shown. n = 3 in each group. Normal bone marrows were from three normal FVB/n mice. Leukemic samples were from nine independent APLs arising from the survival experiments shown in Figs. 1 A, 3 A, and 3 B. Data were obtained from two independent immunoblots; each sample was analyzed once. *, P < .05; **, P < .01 for comparison to normal Cntr bone marrow.
