(A) PCAF mRNA induction in ATRA-treated NB4, HL-60, and APL primary cells. (B) PCAF induction in the bone marrow of APL patients during the ATRA-containing chemotherapy. Day 1 represents the mRNA level prior to the treatment. (C) PCAF knocked-down in HL-60 cells by 3 independent shRNA against PCAF or non-targeting shRNA (control) (Upper left). PCAF knocked-down cells lack a capacity to differentiate into granulocytes (CD11b positive cells) by ATRA-treatment (***; p<0.001, n=3) (lower left, and right).