RNAi against HDAC1 induces BTK-targeting miRs to reduce BTK protein in primary CLL cells. (A-B) Primary CLL cells were nucleofected with small interferring RNA (siRNA) against HDAC1 for 48 hours before being harvested for RNA and protein. The top panel shows the effect of siRNA-HDAC1 on HDAC1 protein. GAPDH was used as a loading control (middle panel). The bottom panel shows the consequence of si-HDAC1 on BTK protein. The figure is representative of 10 independent transfections. (B) Quantitation of the effect of siHDAC1 on HDAC1 protein. Data represent mean ± SEM of 10 CLL samples (P < .01, paired Student t test). (C) The expression of miR-147b, miR-210, miR-425, miR-1253, miR-4269, miR-4667-3p was quantitated in the primary CLL cells nucleofected in (A). Data represent mean ± SEM of 7 CLL samples. (D) The expression of BTK mRNA in the primary CLL cells nucleofected in (A). Data represent mean ± SEM of 7 CLL samples. (E) The expression of BTK protein (P < .05, Wilcoxon signed rank test) in the primary CLL cells nucleofected in (A). Data represent mean ± SEM of 9 CLL samples. *P ≤ .05; **P ≤ .01.