On the other hand, Rho–ROCK activity is critical for the protease-independent rounded motility of tumour cells and cell types with few adhesion contacts (ameboid) when Rho-dependent contractile forces generate hydrostatic pressure forming multiple membrane blebs to invade the ECM (Sahai and Marshall, 2003; Sanz-Moreno et al., 2008). This evidence concerns the gene RHO and neoplasm.