In TGF beta signaling pathway (Figure 7), taking the sub-pathway from TGFB to E2F4/5 as an example, in primary breast cancer, gene DCN (node Decorin) was active, and it inhibited TGFB expression; however, RBL1 (node p107) and E2F5 were active (active sub-pathway DCN-TGFB-RBL1-E2F5); in breast to liver metastatic cancer, TGFB3 (node TGBF) was active, as well as E2F4 (active sub-pathway TGFB3-E2F4). This evidence concerns the gene E2F4 and breast cancer.