Overexpression of MMPs, in particular gelatinase A (MMP-2), gelatinase B (MMP-9) and stromelysin-3 (MMP-11), is related to tumour progression and metastasis in solid tumours including gastric (Schwartz, 1996), colon (Karakiulakis et al, 1997) and lung cancer (Cox et al, 2000b). Here, MMP11 is linked to lung cancer.