The PPIN nodes with degree greater than 13 and BC greater than 63.94 were considered hubs, including COL1A1, COL1A2, COL3A1, COL5A1, COL4A1, FN1, COL5A2, MMP2, ITGA2, SPARC, THBS1, and ITGA5. This evidence concerns the gene COL4A1 and breast cancer.