During cancer progression, C-C motif chemokine ligand 2 (CCL2) and colony-stimulating factor 1 (CSF1) recruit and maintain macrophages in the TME (206), and CSF1-recruited TAMs express TFs, including Ets2, to promote angiogenesis, tumor growth, and breast cancer metastasis (207). This evidence concerns the gene CCL2 and breast cancer.