PIK3CA and osteosarcoma: In contrast, STEAP2 (sixtransmembrane epithelial antigen of prostate 2), zinc finger CCHC domain containing 12 gene (ZCCHC12) (Figure 3E), and fibulin-4 (Figure 4A) are promoters of osteosarcoma, which can be induced by the PI3K/AKT/mTOR pathway to induce EMT and promote tumor growth, invasion and metastasis of osteosarcoma cells (104, 135, 139).