PTK2 and cancer: In cancer cells, FAK has been shown to regulate cell migration and invasion through distinct pathways by promoting the dynamic regulation of focal adhesion and peripheral actin structures (Lauffenburger and Horwitz, 1996; Friedl and Bröcker, 2000; Schlaepfer et al, 2004), as well as the matrix metalloproteinases (MMP)-mediated matrix degradation (Siesser and Hanks, 2006).