May 23, 2017

A CLOUD of Possibilities: Finding New Therapies by Combining Drugs

(c) Nature Chemical Biology / Stefan Kubicek

The CeMM Library of Unique Drugs (CLOUD) is the first condensed set of FDA-approved drugs representing the entire target and chemical space of all clinical compounds. Its potential was shown in a combinatorial high throughput screen at the CeMM chemical screening platform and published in Nature Chemical Biology: A pair of hitherto unrelated drugs proved to be highly effective against multiple prostate cancer cell lines. 

(Vienna, May 22, 2017) The synergy of two combined pharmaceuticals assessed in an experimental setting can reveal completely new therapeutic options. Nevertheless, finding a novel combination of drugs for a given disease within the more than 30,000 drug products approved by the regulatory agencies was hitherto a big challenge for scientists.To facilitate systematic screening for synergistic interactions of drugs, CeMM PI Stefan Kubicek and his colleagues established a collection of 308 compounds (CeMM Library of Unique Drugs, CLOUD) that effectively represent the diversity of structures and molecular targets of all FDA-approved chemical entities. 

Moreover, the scientists proved the potential of the CLOUD with CeMM´s highly automated chemical screening platform by identifying a novel synergistic effect of two drugs (flutamide and phenprocoumon (PPC)) on prostate cancer cells. The results of Kubicek´s team with Marco Licciardello as first author where published in Nature Chemical Biology (DOI:10.1038/nchembio.2382) “The combination induced massive cell death in prostate cancer cells. We then went back to the entire approved drug list, and indeed, we could show that all drugs from the clusters that flutamide and phenprocoumon represent synergize. Thereby we validated the reductionist concept underlying the CLOUD library,” Stefan Kubicek explains. 

With their experiments, Kubicek´s team in collaboration with scientists from the Medical University of Vienna, the Uppsala University, Enamine Kiev and the Max Planck Institute for Informatics in Saarbrücken proved that the CLOUD is the ideal set of compounds to develop screening assays and discover new applications for approved active ingredients. At CeMM, a number of key discoveries on new applications for approved drugs have already been made with the CLOUD. Furthermore, as shown in the current issue of Nature Chemical Biology, the CLOUD is ideal for finding new drug combinations. “In view of these successes, I would predict that this set of compounds will become world standard for all screening campaigns”, Stefan Kubicek emphasizes.


Marco P Licciardello, Anna Ringler, Patrick Markt, Freya Klepsch, Charles-Hugues Lardeau, Sara Sdelci, Erika Schirghuber, André C Müller, Michael Caldera, Anja Wagner, Rebecca Herzog, Thomas Penz, Michael Schuster, Bernd Boidol, Gerhard Dürnberger, Yasin Folkvaljon, Pär Stattin, Vladimir Ivanov, Jacques Colinge, Christoph Bock, Klaus Kratochwill, Jörg Menche, Keiryn L Bennett & Stefan Kubicek. A combinatorial screen of the CLOUD uncovers a synergy targeting the androgen receptor. Nature Chemical Biology, May 22, 2017. DOI:10.1038/nchembio.2382


This study was supported by a Marie Curie Career Integration Grant, the Austrian Federal Ministry of Science, Research and Economy, the National Foundation for Research, Technology, and Development and the Austrian Science Fund (FWF).