HIF1A and neoplasm: This is widely expressed and found in almost all populations of innate and adaptive immunity, and HIF2α, in which the expression is observed in a number of cell types, including endothelial cells associated with tumor macrophages [333,334], etc. It is well known that hypoxia is a typical feature of solid tumors [335] and leads to the HIF1α stabilization in cancer cells, promoting the recruitment of myeloid cells in two ways: Activating chemokine receptors and stimulating the chemokine production, as well as increasing the cytokine secretion.