The deletion mutation abrogates RA-induced APL cell differentiation.

(A) The expression of PML-RARA protein was examined by Western blot analysis with anti-FLAG antibody in established Wt-PML-RARA and mutant- PML-RARA expressing cells. (B) Cell growth assay in established Wt-PML-RARA and mutant-PML-RARA expressing cells. (C, D) Mean fluorescence intensity (MFI) ratios of CD11b to isotype controls in ATRA- (C) and tamibarotene- (D) treated Wt-PML-RARA and mutatnt-PML-RARA expressing cells. The cells were treated with 1 μM of ATRA or tamibarotene for seven days. Error bars represent mean values ± S.D. of at least three independent experiments. (E) Frequencies of NBT reduction of neutrophils. Cells were treated with 1 μM ATRA or tamibarotene for seven days. Error bars represent mean values ± S.D. of at least three independent experiments.