Active MMP-7 not only degrades ECM but also activates other potential forms of MMPs, such as MMP-2 and MMP-9. As for MMP-9 aka gelatinase B, its precursor can be secreted by monocytes, macrophages, neutrophils, vascular smooth muscle cells, endothelial cells, foam cells, fibroblasts, microglial cells, and tumor cells (11–13). Here, MMP9 is linked to neoplasm.