Figure 1: A PPI network construction by mapping 244 DEPs to a web-based HAPPI database and its topological features.

(A) The seeds of 244 DEPs were mapped onto HAPPI database and were expanded to their first-degree neighbors, resulting in an extended network with 22 604 interactions between 6392 nodes. Different colors denote nodes with different degree and k-shell. (B) The degree distribution of the PPI network. (C) The contributions of the two factors in terms of factor scores versus
are 52.25% and 43.71%, respectively.