PIK3CA and neoplasm: A downstream target of PI3K/AKT is mTOR, activation of which results in phosphorylation of ribosomal protein S6 kinase (S6K) and eukaryotic translation initiation factor 4E (eIF4E)‐binding protein 1 (4EBP‐1), permitting the transcription, proliferation, growth, and protein synthesis of tumor cells [7, 9, 24, 26, 27] (Figure 1).