CASP3 and tongue cancer: To further verify the inhibitory effect of activated GSK-3β on tongue cancer, we used the selective GSK-3β inhibitor kenpaullone (KP) to treat IL-18-transfected CRL1623 cells and found that KP reduced GSK-3β phosphorylation and its activation, in turn inhibiting the activity of caspase-3 and -7 (Fig. 4B).