PIK3CA and neoplasm: ALK forms a tyrosine kinase active dimer with its fusion partner, Activate ALK and its downstream Rat Sarcoma virus-Mitogen Activated Protein Kinase(RAS-MAPK) and Phosphatidylinositol 3 Kinase/protein kinase B(PI3K-AKT) signaling pathway, thereby causing abnormal cell proliferation and differentiation, forming a powerful tumor driving force, leading to malignant tumor proliferation.