Expression of cyclins A and D in leukemia cells. TF-1 (A) or K562 (B) myeloid leukemia cells were transduced with control and CREB shRNA lentivirus and synchronized. At 12 hours, 5 μg of total RNA was isolated for q-PCR by SyberGreen method. Cyclin A1- and D1-specific primers were used, and expression was normalized to the house keeping gene β-actin. Experiments were performed in triplicate. Error bars represent SE.