Interestingly, comparing all BC subtypes we found that TNBC and HER2 positive BC subgroups exhibit the highest expression levels of S100A8 and S100A9, as determined exploring two diverse public BC datasets (Additional file 3: Supplementary Fig. S3F-G; Additional file 4: Supplementary Fig. S4A-C). This evidence concerns the gene S100A9 and breast cancer.