Fig. 1

First neighbours have a central position in cellular signalling networks. a The signalling network of colon cancer (interactions based on the SignaLink resource). Node sizes are proportional to their betweenness centrality network parameter. Green nodes represent cancer-related proteins, orange nodes are their first neighbours and grey nodes represent the proteins that do not belong to any of these categories (here termed as “unaffected” proteins). Based on cancer-relatedness, sub-graphs have been created, with their major network properties shown below them. Note the different ratio of nodes in the giant component, which is the largest connected graph. (Exact test *** p < 0.001) b Distribution of network topological properties for each subgraph: degree (local centrality), betweenness centrality (global centrality), and clustering coefficient (neighbourhood connectivity). White dots represent median values, boxes stretch from the 25th percentile to the 75th percentile, and whiskers are twice the length of the boxes. Wilcoxon rank sum tests have been used for statistical testing, with the whole network serving as control. The level of significance is represented using the following scale: *p < 0.05, **p < 0.01, ***p < 0.001