This was somewhat expected considering reports that several MMPs, including gelatinase B/MMP-9, display anti-tumor activity [72,112,113,284,285,402,403], different MMPs may be involved in different stages of tumour progression and the most potent endogenous gelatinase B/MMP-9 inhibitor, TIMP-1 may promote scattered micro-metastases in the liver [404]. The gene discussed is MMP9; the disease is neoplasm.