MLC1 and fibrosarcoma: Figure 6a shows that all three inhibitors caused fs164 and fs120 cells to switch to a mesenchymal morphology (compare Figure 6a with Figure 1) and accelerated their migration but not that of fswt and fs188 cells (Figure 6b). P6 inhibited MLC phosphorylation in all the fibrosarcoma cells (Figure 6c) as previously shown for melanoma cells [30] but interestingly also induced a marked up-regulation of integrin β1 (Figure 6c).