CDH1 and gastric cancer: We next measured signaling activity of the PI3K-AKT and MAPK pathway in hereditary c.1380delA CDH1 SB.mhdgc.-1 gastric cancer cells versus a panel of sporadic gastric cancer cell lines by determining ratios of phosphorylated Akt, PDK1, and ERK1/2 (MAPK42/44) to total Akt, PDK1, and ERK kinase levels.