Luciferase activity determination. (A) The changes of luciferase activity after PirGLO- CREB1-3’UTR normal plasmid co-transfecting with miR-1468 mimics (miR-1468-mi group) and mimics reference substance (NC group) for 48 h. Compared with NC group, the column marking** showed extremely significant difference (P<0.01); (B) The changes of luciferase activity after PirGLO-CREB1-3’UTR mutant plasmid plasmid co-transfecting with miR-1468 mimics (miR-1468-mi group) and mimics reference substance (NC group) for 48 h. Compared with NC group, the column without marking**or* showed no significant difference (P>0.05).