DKK1 and pancreatic ductal adenocarcinoma: Kimura et al. [27] found that the inhibition of DKK1 using antibodies decreased p-Akt expression in pancreatic ductal adenocarcinoma cells, and Lyros et al. [64] found that DKK1 inhibition using siRNA decreased p-Akt expression in esophageal adenocarcinoma cells.