PIK3CA and gastric cancer: The PIK3CA gene, which encodes phosphatidylinositol-4,5-bisphosphate 3-kinase catalytic subunit alpha, is mutated in a number of tumors, including glioblastomas, gastric cancers, lung cancers, ovarian cancers, hepatocellular carcinomas, endometrial carcinomas, brain cancers, and breast cancers [7].The higher frequency of PIK3CA missense mutations in luminal breast cancer samples prompted us to ask how PIK3CA mutations interact with other mutated genes to trigger cancer progression and metastases.