1. Supplemental Figure 1. Specificity of CCL2 and Fsp1 immunostaining of breast tumor tissues. Sections of invasive ductal carcinoma were incubated with primary antibodies to CCL2 and Fsp1. CCL2 was detected using anti-goat biotinylated secondary antibodies. Fsp1 was detected using anti-rabbit-biotinylated secondary antibodies. Staining specificity was determined by incubating sections with secondary antibodies only or incubating sections with primary antibodies with 5 fold excess blocking peptide to CCL2 or Fsp1. Scale bar= 100 microns. CCL2 Primary antibody+ Secondary antibody Primary antibody+ blocking peptide+ Secondary antibody Secondary antibody only Fsp1

2. p=0.0158 r=0.6096 Supplemental Figure 2. Image J analysis significantly correlates with manual scoring of CCL2 and Fsp1. A. Image J values for epithelial CCL2 staining were cross referenced to samples manually scored weak or strong were. B. Image J values for total Fsp1 expression analyzed for associations with manual scoring. * CCL2 (weak) CCL2 (strong) Epithelial CCL2 0.4 0.3 0.2 0.1 0.0 0.8 0.6 0.4 0.2 0.0 0.80.60.40.20.01.0 Total Fsp1(Image J values) Total Fsp1 (Manual Score) A B

3. ** * Supplemental Figure 3. Stromal CCL2 expression inversely correlates with overall stage and T stage in basal-like breast cancer. Stromal CCL2 expression was analyzed for associations with A. overall stage and B. T stage. Statistical analysis was performed using Mann- Whitney’ test (overall stage) or Kruskal-Wallis test with Dunn’s post-hoc comparison (T stage). Statistical significance was determined by *p<0.05; **p<0.05. A B