Drug-cancer SL network representing the set of cancer-related nodes and their SL drug-associated partners (Additional file 8). Triangles represent cancer-related nodes and circles, SL drug-associated partners. Red color indicates that this node has associated a gene which is target of anti-cancer drug. Green color indicates a non-cancer drug associated to the node. Blue color only appears in triangles representing that there is no drug in the DrugBank database associated to these cancer-related genes. Essential genes are overlined. Large nodes are examples of existent anti-cancer drug target with a cancer-related SL pair (PPP6C-PSMB2, BUB1*-TUBB*, ERCC2-DCK7), and also our suggested examples of novel use for existent cancer-unrelated drugs that target a SL partner of a cancer-related gene (RAD50-PRDX2, MRE11A-PRDX2 AND PPP6C-CDC42). The BUB1* node represents BUB1 and BUB1B genes, whereas TUBB* node includes TUBB2B, TUBB3, TUBB2A and TUBB6 tubulin family members.