Expression of genes associated with differentiation in ATRA resistant APL cells. NB4.306 cells were treated for 24 hrs (left panels) or 48 hrs (right panels) with ATRA (0.5μM), atorvastatin (2μM), or the combination of ATRA and atorvastatin, as indicated. Expression of mRNAs for CCL3 (A), IL1B (B), BTG2 (C) or NCF2 (D) was evaluated by quantitative real time RT-PCR (TaqMan), using GAPDH for normalization. Data are expressed as fold increase over untreated samples and represent means ± S.E. of 2-independent experiments.