The heat map as shown in Supplementary Figure 2 represents the changes in the relative content of type I pro-collagen alpha 1 chain (COL1A1) and type III procollagen alpha 1 chain (COL3A1) in 15 metastatic breast cancer cell lines and 11 non-metastatic breast cancer cell lines. The gene discussed is COL1A1; the disease is breast carcinoma.