CXCL8 and neoplasm: In particular, conditioned media from human breast adenocarcinoma cells were found to contain soluble factors playing a crucial role for the recruitment and adhesion of myeloid cells to the tumor, including macrophage inflammatory protein-1β (MIP-1β), vascular endothelial growth factor-α (VEGF-α), IL-8, IFN-γ and granulocyte colony-stimulating factor (G-CSF) [56].