More importantly, TA-MSCs can recruit macrophages and myeloid-derived suppressor cells (MDSCs) into the tumor microenvironment through CC-chemokine receptor 2 (CCR2) ligands, including CC-chemokine ligand 2 (CCL2), CCL7, and CCL12 (Ren et al., 2012). Here, CCL2 is linked to neoplasm.