Compared with differential expression analysis, our hub genes mostly acted as gatekeepers or core relays in multiple important pathways, such as FZD8/9, controlling the entry of canonical Wnt pathway, or RRAS2, which dominate Ras signaling pathway and proven to be associated with anti-breast cancer drug tamoxifen (Mendes-Pereira et al., 2012). This evidence concerns the gene RRAS2 and breast cancer.