TIMP1 and neoplasm: For example, tumor cell-derived exosomes may be enriched in angiogenic factors such as angiopoietin, IL-6, IL-8, vascular endothelial-derived growth factor (VEGF), tissue inhibitor of metalloproteinase 1/2 (TIMP-1/2), and other angiogenic factors, to activate EC function and enhance their activity to stimulate angiogenesis [97].