Table 1.

Features of the metabolic networks considered in the paper

	Human [[25]]	Cancer [[14]]
Number of reactions	2469	940
Number of metabolites	1587	654
Number of compartments	8	8
Number of pathways	83	62
Number of drugs	85	55

The human network has been obtained from BIGG (http://bigg.ucsd.edu/), whereas the cancer network has been provided us by the authors of [14]. The number of reactions here reported is before the splitting of every reversible process in a pair of irreversible reactions. Drugs have been selected from DrugBank database [26] as described in Methods. The complete list is reported in Additional file 1: Table S1).