Mobilization followed by increased mobility of endothelial cells is also orchestrated by the products of the secretome of cancer cells, PMCs, and PFBs, e.g., ovarian cancer cells secrete high amounts of CXCL1/GRO-1, CXCL8/IL-8, IL-6, HGF, and VEGF [87], whereas PMCs generate constitutively CXCL1/GRO-1, CXCL12/SDF1, bFGF, MMP-2, MMP-9, and VEGF [124, 125]. This evidence concerns the gene MMP9 and cancer.