KDR and neoplasm: Since it has been described that ARF inhibits angiogenesis by stimulating the expression of tissue inhibitor of metalloproteinase-3 (TIMP-3) [22], and TIMP-3 has been shown to inhibit VEGFR-2 and adhesion molecules as VE-cadherin or VCAM- 1 [23–25], we further explored levels of TIMP- 3 in B16F10-ARF−/− tumor xenografts.