PTK2 and prostate cancer: Unpublished observations from our group also support the biochemical association of CXCL8 with Src and FAK-induced chemotaxis and adhesion to bone marrow endothelial cells (a common clinical site of extravasation), while studies on prostate cancer biopsy tissue demonstrate that expression of CXCL8 correlates with increased FAK and Src phosphorylation [64].