A central role for a transmembrane member of the MMP family, membrane-type 1 MMP (MT1), in cancer metastasis has emerged in association with the aggressive behaviour of several cancer types (Aznavoorian et al, 2001; Seiki, 2003; Ueda et al, 2003; Sabeh et al, 2004; Cao et al, 2005), as reviewed by Sounni and Noel (2005). The gene discussed is MT1F; the disease is cancer.