This project will establish a computational strategy which exploits polypharmacology to identify drug targets in biological systems implicated in cancer. The value of our polyphamacology platform will be tested by application to glioblastoma multiforme, a deadly brain cancer. The aim will be to identify multiple targets in protein networks linked to glioblastoma to thereby enable repositioning of drugs against that cancer. The novelty of the work will lie in its use of protein domain structure data to link known and putative drug compounds to biological networks.The project is proposed as an interdisciplinar and intersectoral research: (i) It will be developed on the basis of the domain structure resources and expertise in the host group of Prof. Orengo at University College London (UCL), and the compound-target libraries and drug discovery expertise within the pharmaceutical company GlaxoSmithKline, which will be a seconded host institution; (ii) it will benefit from the expertise in protein-ligand interactions developed in the group of Prof. Janet Thornton and the group of Prof. John Overington at the European Bioinformatics Institute; (iii) the experimental testing of putative drug compounds will be undertaken in collaboration with the group of Dr Matilda Katan-Muller at UCL and the group of Prof David Selwood at UCL.