CCL2 and breast cancer: Th2 cells produce IL‐4, IL‐5, IL‐13, chemokine ligand 2 (CCL2) also referred to as monocyte chemoattractant protein 1 (MCP‐1), CCL7, and CCL11 that stimulate antibody production by B cells and M2 macrophage polarization that are essential in mediating a humoral immune response reported to enhance mammary tumor development.23, 24