Speciation analysis in preclinical drug development

In an interdisciplinary approach we will seek to implement analytical methods capable of assaying metallodrug - biomolecule interactions in preclinical drug development. It is now widely accepted that knowledge obtained by extensive preclinical assessment essentially contributes to the successful development of new anticancer compounds. The novel bioanalytical strategies will be established for known binding partners of metallodrugs as metallothioneins and glutathione, both involved in cellular detoxification processes. These investigations form a prerequisite for the ultimate goal, namely establishing high throughput methods for studying metallodrugs - biomolecule association. Understanding these types of interactions plays a key role in many aspects essential for successful drug development. In the planned project we will focus on resistance. In clinical practice, development of chemotherapy resistance is the major impediment for successful curative treatment of cancer patients at the advanced, disseminated stage. Consequently, this biological phenomenon represents not only the central reason for the still unacceptable high number of cancer deaths but also a major economical health problem. We will study already successfully used drugs as cisplatin and oxaliplatin and two promising novel lead substances, an oxaliplatin analogue and a ruthenium compound currently scheduled for clinical trial phase1b. The interdisciplinary study capitalizes already established collaborations between the BOKU Vienna (Analytical Chemistry), the Medical University of Vienna (Tumour Cell Biology) and the University of Vienna (Inorganic Chemistry). Speciation analytical methods employing multidimensional separations with elemental and molecular mass spectrometric detection will be integrated in cell biological and preclinical studies. As a novelty, the methods will deliver both quantitative data and structural information on formation metallodrug adducts and will hence give novel insights into drug- biomolecule interaction patterns in living cells and their impact on drug activity.

The project dealt with the development of novel analytical strategies in the (pre)clinical development of metallodrugs establishing an unique link between analytical chemistry and preclinical cancer research. Major focus was the assessment of metallodrug - biomolecule interaction in vitro and in vivo, since adduct formation with biomolecules might be in part responsible for the cytotoxic activity of these drugs. Hence, understanding these types of interactions plays a key role in many aspects essential for successful drug development. Surprisingly, even for the clinically established anticancer platinum drugs the knowledge on intracellular events is fragmentary, since most intracellular targets are deduced from ex vivo incubations in solutions mimicking biological situations. Moreover, in recent years, the mechanisms of metallodrug-induced cell death was extensively studied using exclusively biological/biochemical methods, i.e. addressing the involvement of the drugs in biochemical processes and signaling pathways in preclinical (cell models) and clinical samples. In this project complementary quantitative information on drug uptake, efflux, intracellular stability, drug-protein adduct formation could be obtained, revealing novel insights into drug activity profiles and resistance mechanisms.