MMP9 and neoplasm: Inflammation occurs in the tumor microenvironment, which in turn accumulates a large number of cytokines, chemical mediators and enzymes, such as TNF-a, IL-6, VEGF, iNOS, Cox-2, and MMP-9, for mediating inflammation and driving its malignant transformation (Gasparini et al., 2003; Balkwill et al., 2005; Kulbe et al., 2007; Lawrence, 2007; Lin and Karin, 2007).