GDF5 and breast cancer: As an illustration for the down-regulated genes by BC, GO: MF signaling receptor regulator activity GO:0030545 with 22:554 genes, comprising a series of genes, including GDF5, GDF15, BMP4, FGF13, FGF18, IL34, WNT2B, and CCL11 showing paracrine factors, is also diminished by BC (Supplementary Figure S2 and Table S7).