Our data show that the activation of Rho, ROCK, the phosphorylation of MLC and non-muscle myosin II ATPases activity is necessary for effective invasiveness of both A3 and PR9692 sarcoma cells, and that the activation of Rho and MLC phosphorylation is necessary for the effective metastasis of PR9692 cells. The gene discussed is MLC1; the disease is sarcoma.