MMP9 and neoplasm: Lung tumor–associated NK cells (TANKs) of peripheral blood and tumor-infiltrating NK cells (TINKs) induced functional angiogenesis-associated behaviors of endothelial cells in vitro. TANKs release TIMP-1, TIMP-2, and MMP-9, proteins involved in tissue remodeling and invasion process. They also increase the expression the angiogenin, VEGF and CXCL8, depending on tumor location