Fig. 4

Dynamical changes in the network for the progression of two diseases. To validate the results from HMM-based method, we show the dynamical evolution of the network structure for the two diseases. For each network, the color of nodes represents the fluctuation of expression, and the thickness of links stands for the correlation between each pair of nodes. a For HCC, the figures show the dynamical changes of the human molecular network (3425 genes and 5826 edges) at 4 sampling stages, i.e., low-grade dysplastic stage, high-grade dysplastic stage, very-early HCC stage, early HCC stage. The subnetwork composed by selected 230 genes (from Fig. 3 c) is placed at the top corner. It can be seen that at the “very-early HCC" stage, there is a significant change in the selected subnetwork, which signals the upcoming deterioration into HCC. b For live influenza infection, it shows the dynamical changes of the human molecular network (3839 genes and 7281 edges) at 4 sampling time points, i.e., 5 hr, 12 hr, 29 hr, 60 hr. The subnetwork composed by selected 180 genes (from Fig. 3 d) is placed at the top corner. Obviously, at 29 hr the structure of the selected subnetwork exhibits the most significant change, which suggests the pre-disease stage around 29 hr and presents a warning signal for the imminent deterioration into the influenza infection. It is worth noting that the critical phenomena in the network structure only appear when the system is near the critical transition point