These results were consistent with our finding that the CXCL1/CXCL2/CXCL5 and S100A8/S100A9, which were chemoattractants for N1 and N2 neutrophils, respectively, played an antitumor or pro-tumor role in breast cancer metastasis, respectively. This evidence concerns the gene CXCL2 and breast carcinoma.