PIK3CA and neoplasm: In colon cancer, tumor-derived exosomes containing miR-10b are transferred to fibroblasts in which Phosphatidylinositol-4,5-bisphosphate 3-kinase Catalytic Subunit Alpha (PIK3CA) expression is significantly suppressed by downregulation of PI3K/Akt/Mechanistic target of Rapamycin Kinase (mTOR) pathway activity.