MMP9 and neoplasm: Toll-like receptor 4 signalling in colon cancer cells is involved in tumour immune escape, accompanied by apoptosis resistance and the preferential induction of immunosuppressive factors and chemokines, such as TGF-β, NO, IL-8, MCP-1, and MMP-9, resulting in tumourigenesis and the promotion of tumour metastasis (Cianchi et al, 2004; Molteni et al, 2006; Wang et al, 2003, Lee and Lim, 2007).