It was found that hypoxia upregulates MCP-1 in VSMCs, in addition to causing macrophage chemotaxis and upregulating IL-6 expression in THP-1 cells, which in turn leads to apoptosis via STAT1 in VSMCs.220 On the other hand, Mcp-1 can also promote aneurysm repair.221 Slow-release Mcp-1 promoted carotid aneurysm growth and healing in mice in a dose-dependent manner. This evidence concerns the gene CCL2 and aneurysm.