Genes within this functional family that may be relevant to tumor progression encode cathepsins B, C, D, Z, legumain, a disintegrin-like and metalloprotease reprolysin type with thrombospondin type 1 motif 4 (ADAMTS4), matrix metalloproteinases 2 and 3 (MMP2, MMP3), and FURIN, which processes latent precursor proteins into their biologically active counterparts (Table 1). The gene discussed is FURIN; the disease is neoplasm.