Illicit-extended drug-target network, highlighted with hubs. Nodes with readable labels are hubs, which were defined by their degrees being greater than eight. Rectangular nodes in green correspond to illicit drugs, triangular nodes in green correspond to illicit-related drugs, and circle nodes in red correspond to target genes. Red edges represent the interactions between illicit drugs and their target genes and grey edges represent the interactions between illicit-related drugs and their target genes that are also targeted by illicit drugs. Font size corresponds to the degree of interactions.