Abstract
The motile behavior of non-muscle cells often differs between healthy and pathological conditions. Two disease processes, cancer and atherosclerosis, are associated with high morbidity and mortality in our society. The cells involved in both the pathogenesis of and me defense against these diseases undergo marked changes in the organization of their actin cytoskeletonl1,2. In response to a signal originating from the extracellular space, from surrounding cells, or as the result of a mutation, diseased cells initiate a process of motion away from their normal location. Local growth inhibitors are lost, and displaced cells undergo unchecked proliferation1. One example of such a phenomenon is the migration of fibroblasts and smooth muscle cells into the vascular intima and their proliferation in patients with atherosclerotic coronary artery disease2. Another example is the proliferation of metastatic cells distant from the site of primary tumor1.