TIMP-2 is a serine protease inhibitor that inhibits MMPs. It is known to act on MMP-1, MMP-2, MMP-3, MMP-7, MMP-8, MMP-9, MMP-10, MMP-13, MMP-14, MMP-15, MMP-16 and MMP-19 []. As opposed to other TIMPs, TIMP-2 abrogates angiogenic factor-induced endothelial cell proliferation in vitro and angiogenesis in vivo independent of MMP inhibition. These effects require alpha 3 beta 1 integrin-mediated binding of TIMP-2 to endothelial cells. Further, TIMP-2 induces a decrease in total protein tyrosine phosphatase (PTP) activity associated with beta1 integrin subunits as well as dissociation of the phosphatase SHP-1 from beta1. TIMP-2 treatment also results in a concomitant increase in PTP activity associated with tyrosine kinase receptors FGFR-1 and KDR [].Tissue inhibitors of metalloproteinases (TIMPs) are natural inhibitors of matrix metalloproteinases (MMPs) found in most tissues and body fluids. By inhibiting MMPs activities, they participate in tissue remodeling of the extracellular matrix (ECM). The balance between MMPs and TIMPs activities is involved in both normal and pathological events such as wound healing, tissue remodeling, angiogenesis, invasion, tumourigenesis and metastasis []. TIMPs also exhibit functions that appear to be independent of their metalloproteinase inhibitory capacity []. There are four mammalian TIMPs (TIMP-1 to -4), and each TIMP has its own profile of metalloproteinase inhibition.
