However, inhibition of total pericellular proteolysis (by inhibiting MMPs, cathepsins, uPA, etc.)attenuates mesenchymal migration, often leading to the mesenchymal-to-amoeboid transition (MAT) in which cells obtain flexible, “pathfinding” amoeba-like characteristics, as observed for HT-1080 fibrosarcoma and MDA-MB-231 carcinoma cells [89]. This evidence concerns the gene CTSS and fibrosarcoma.