CXCR4 and neoplasm: Shioppa and colleagues found that hypoxiaincreased CXCR4 mRNA and cell-surface protein expression in several cell types,including monocytes, human monocyte-derived macrophages, tumor-associatedmacrophages, HUVECs, CAOV3 ovarian carcinoma cells, and MCF-7 breast carcinomacells, leading to increased migration towards CXCL12 due to the activation ofHIF-1 [132].