HIF1A and neoplasm: Currently, copper has been found to play an important role in the high-affinity copper transporter (CTR-1) (32), LOX (33), hypoxia-inducible factor (HIF-1α) (34), antioxidant protein-1(ATOX-1) (35, 36), RAS-RAF-MEK-ERK signaling pathway (37) (38, 39) and PD-L1 (40), which are associated with tumorigenesis, adaptation to hypoxic environment (41), tumor extracellular matrix construction(ECM), neovascularization, epithelial to mesenchymal tissue transition (EMT) and tumor metastasis.