CREB1 and acute lymphoblastic leukemia: Whereas none of the BCP-ALL samples responded to the drug despite high CREB phosphorylation, all 4 primary T-ALL samples showed sensitivity to the drug in a dose-dependent manner (Figure 7C and 7D, LC-50 values for T-ALL 1, 2, 3, and 4 were 10.32 μM, 7.16 μM, 9.07 μM, and 45.90 μM, respectively).