 ROCK1 activation by RhoA also promotes stabilization of F-actin, phosphorylation of regulatory myosin light chain (MLC) and an increase in contractility, which plays a crucial role in tumor cell migration and metastasis.This activated ROCK1 also activates LIM kinase, which, phosphorylates cofilin, inhibiting its actin-depolymerizing activity.This depolymerization results in stabilization of actin filaments and decreased branching which promotes contraction.