PIK3CA and neoplasm: Others have shown that NOTCH2 possessed a tumor suppressor function in gastric cancer by modulation of the PI3K/Akt pathway and MMP9 suggesting the importance of physiological levels of NOTCH2 expression in preventing stomach carcinogenesis [37], supported by another report of higher NOTCH2 expression in early-stage gastric tumors as compared to advance-stage tumors [38].