Chemokines such as CXCL12-CXCR4, CCL2-CCR2, and CX3CL1-CX3CR1 guide the lamellipodia of melanoma cells to intercellular junctions, where the cells can secrete MMP2, MMP9, and heparanase locally to transiently disrupt the endothelial basement membrane [61]. The gene discussed is CXCL12; the disease is melanoma.