PIK3CA and neoplasm: As one of the most disrupted pathways in cancer, various activating mutations in oncogenes as well as inactivation of tumor suppressor genes can trigger abnormal activation of the PI3K/AKT/mTOR signaling pathway, which in turn regulates autophagy to participate in the malignant biological behaviors and prognosis of many types of tumors (Polivka and Janku, 2014).