While no significant difference in mRNA levels of S100A8 and S100A9 were detected between ER+-breast tumor tissues and their corresponding tumor-adjacent tissues (Figure 5B); The S100A8 and S100A9 were highly expressed and their mRNA levels were significantly higher in ER--breast tumor tissues than in their corresponding tumor-adjacent tissues (Figure 5C). This evidence concerns the gene S100A9 and breast neoplasm.