Characterizing combinatorial regulation in the subnetworks. (A) An illustration of the identified key active subnetworks. Identified key transcription factors form the inner ring and their target genes the outer ring. Target genes are colored based on whether they are more highly expressed in the angiogenic (red) or non-angiogenic subtype (blue) and are organized based on their classification. Angiogenic subnetwork edges (red) and non-angiogenic subnetwork edges (blue) extend between these rings, from the regulating transcription factor in the inner ring, to its target gene in the outer ring. (B) A table of the top three co-regulatory TF-pairs targeting “A+” genes, (C) a diagram illustrating these co-regulatory interactions, and (D) a Venn-diagram showing the overlap of the “A+” genes targeted by these TFs. (E) A table of the top three co-regulatory TF-pairs targeting “N-” genes, (F) a diagram illustrating all significant co-regulatory events between these TFs in “N-” genes, and (G) a Venn diagram showing the overlap of “N-” genes targeted by each of these TFs.