BMP4 and basal cell carcinoma: In addition, the DEGs with high degree values (including FN1, ITGB6, COL1A2, ITGA11, LAMB2, ITGA5, ITGA3, and ITGB5) were involved in ECM–receptor interaction; LEF1, FZD3, PLCB2, and SMAD3 were involved in Wnt signaling; LEF1, FZD3, PTCH2, GLI3, PTCH1, SHH, and BMP4 were involved in basal cell carcinoma; FST, BMPR2, SMAD7, ACVR1B, THBS1, BMP4, and SMAD3 were involved in TGF-β signaling; NOTCH2, MAML3, and DTX4 were involved in Notch signaling; and LEF1, DLG2, FZD3, BMPR2, SMAD7, YWHAZ, DLG4, YAP1, BMP4, and SMAD3 were involved in the Hippo signaling pathway.