Nevertheless, CCL2 is produced by a variety of cell types, including endothelial cells and smooth muscle cells [33], astrocytes as a major source of CCL2 during central nervous system inflammation [34] and cancer and stromal cells as a major source of CCL2 in tumour microenvironments [35]; thus, the cellular sources of CCL2 during anaphylaxis are currently unknown. The gene discussed is CCL2; the disease is cancer.