CCR2 and neoplasm: At the same time, there was a large overlap between the genomes of PMN-MDSCs and M-MDSCs involved in immunosuppression, such as IL-1B, ARG-2, CD84, and WFDC17, and chemokine receptors, such as CCR2 and CXCR2, revealing that MDSCs could be migrated to the primary tumor by tumor-derived chemokines.