MMP-9 is produced by a variety of cells, including epithelial cells, fibroblasts, keratinocytes, osteoblasts, dendritic cells, macrophages, granulocytes, and T-cells [29]; however, its expression can be induced in cases of tissue remodeling, such as embryonic development, scarring, or growth, as well as tumor invasion [30,31]. The gene discussed is MMP9; the disease is neoplasm.