PIK3CA and esophageal cancer: Our current findings showed for the first time that wortmannin and LY294002 significantly enhanced the sensitivity of parental esophageal cancer cells and chemoresistant sublines to chemotherapeutic drugs not only in vitro, but also in xenografted animal models (Figures 6-7), which strongly suggest that combining PI3K/AKT inhibitors and conventional chemotherapeutic drugs may be a potentially useful therapeutic strategy in treating esophageal cancer patients, particularly as upfront therapy before tumors have a chance to develop chemoresistance.