CCL2 is mainly expressed by BMSCs, along with other cells facilitating tumor metastasis such as bone marrow‐derived dendritic cells (BMDCs), fibroblasts, endothelial cells, smooth muscle cells, etc. These observations suggest that the interaction between FBXW7, NOTCH, and CCL2 can be a crucial driver event of cancer metastasis. The gene discussed is CCL2; the disease is cancer.