Epac1

Western blotting was performed as previously described.^{15 (link)} The following primary antibodies were used: antibodies against HDAC8, Epac1, Epac2 and glycogen synthase kinase-3β (GSK-3β) were purchased from Santa Cruz Biotechnology; antibodies against cAMP response element binding protein (CREB), p-CREB, p-PKA substrates, Rap1, p-Akt, Akt, p-GSK-3β, p-β-catenin, p-MKK4, MMK4, p-JNK, JNK, Myc, poly (ADP-ribose) polymerase (PARP), cleaved caspase-3 and cleaved caspase-9 were purchased from Cell Signaling Technology (Beverly, MA, USA); antibodies against TIPRL were purchased from Abcam (Cambridge, UK); an antibody against β-actin was purchased from Sigma-Aldrich. The proteins were visualized with the Enhanced Chemiluminescence (ECL) reagent (Thermo Fisher Scientific, Waltham, MA, USA) and detected using an LAS-3000 luminescent image analyzer (Fuji, Tokyo, Japan). The densities of the visualized bands were quantified using the Multi Gauge v.2.3 software (Fuji). The densities were normalized to corresponding control densities and expressed relative to the control.