PTK2 and cancer: These include Y397 (p-PTK2), the autophosphorylation site of focal adhesion kinase (PTK2/FAK) critical for PTK2 activation and interaction with downstream partners such as 118Y-p-Paxillin, an adapter proteins and partner of PTK2 in focal adhesion signaling and regulation of focal adhesion turnover during cancer cell locomotion; and 416Y-p-Src, which regulate Src multiple downstream signaling pathways, including Src interaction with PTK2 during in cell migration and invasion.