Figure 3

Changes in mutual information vs. expression changes. Each dot corresponds to a lost edge in the tumor network. X-axis represents the difference in mutual information (T-N), while the y-axis contains the expression difference between tumor and normal for either the TF or the target gene of that edge. Thus, every edge is represented by two dots in the plot. The area colored in red, where most of the dots fall, corresponds to lost interactions in the tumor (ΔMI < -0.25) in which there is no transcriptional silencing neither of the TF nor the target gene. The fact that most of the edges (~96%) fall in that region suggests that genetic or epigenetic silencing is not involved in this massive loss of transcriptional regulation in tumor cells.