It has been shown that matrix metalloproteinase-1 (MMP-1) causes activation of PAR1 leading to expression of the pro-angiogenic secreted chemokines CXCL8 (IL-8), CXCL1 (GRO-α), and CCL2 (MCP-1) by the cancer cells [42]. Here, CXCL1 is linked to cancer.