CXCL8 and neoplasm: IL-6, CXCL8, and epidermal growth factor (EGF) secreted by tumor cells improve the survival rate and angiogenic potential of endothelial cells through the activation of STAT3/ protein kinase B (AKT)/extracellular signal-regulated kinase (ERK) signaling pathways, respectively [95], while VEGF secreted by endothelial cells can enhance the migration of tumor cells and protect them from apoptosis [96].