However, considering the significant validation tests related to nonhubs (nodes with lower K, BC), including NID2, MXRA5, FKBP10, SULF1, THY1, AEBP1, TGM2, CDH17, CDH6, TGIF1, IGFBP2, and PAPPA, we hypothesize that these nodes can be associated with hubs and have the potential to be GC biomarkers. This evidence concerns the gene PAPPA and breast cancer.