Invadopodia: specialized cell structures for cancer invasion.

The spread of cancer cells to distant sites in the body is the major cause of cancer patient death. Growing evidence connects specialized subcellular structures, invadopodia, to cancer invasion and metastasis. Invadopodia, or invasive foot processes, are actin-rich protrusions that localize matrix-degrading activity to cell-substratum contact points and represent sites where cell signaling, proteolytic, adhesive, cytoskeletal, and membrane trafficking pathways physically converge. Understanding how invadopodia form and function should aid in the identification of novel targets for anti-invasive therapy.