Inhibition of CHD4 does not sensitize normal CD34⁺ progenitor cells to DNR and ara-C. CD34⁺ hematopoietic progenitors were isolated from the 3 normal donors. Depletion of CHD4 did not significantly increase the sensitivity of the CD34⁺ cells to either (A) DNR or (B) ara-C. (C) The CD34⁺ cells were found to contain significantly more endogenous CHD4 protein than the AML cell lines (U937, MV4-11, AML-3) and primary AML blasts isolated from the bone marrow of 3 patients. Interestingly, there was no difference in CHD4 mRNA between the CD34⁺ and AML cells. *P < .05. N.S., not statistically significant.