PIK3CA and esophageal cancer: It is known that activation of PI3K/Akt pathway plays a crucial role in progression and metastasis of esophageal cancer.32 To investigate the potential contribution of the PI3K/AKT pathway in poorly differentiated esophageal adenocarcinoma, we compared the expression of PI3Kp85 (regulatory subunit), Akt and its downstream substrates PRAS40 and p70S6K in normal HET-1A cells and PDEAC cell lines ESO-26 and OE33.