2009 Biospecimen research network symposium: advancing cancer research through biospecimen science.

This report details the proceedings of the 2009 Biospecimen Research Network (BRN) Symposium that took place on March 16 to 18, 2009, the second in a series of annual symposia sponsored by the National Cancer Institute Office of Biorepositories and Biospecimen Research. The BRN Symposium is a public forum addressing the relevance of biospecimen quality to progress in cancer research and the systematic investigation needed to understand how different methods of collection, processing, and storage of human biospecimens affect subsequent molecular research results. More than 300 participants from industry, academia, and government attended the symposium, which featured both formal presentations and a day of workshops aimed at addressing several key issues in biospecimen science. An additional 100 individuals participated via a live webcast (archived at http://brnsymposium.com). The BRN Symposium is part of a larger program designed as a networked, multidisciplinary research approach to increase the knowledge base for biospecimen science. Biospecimens are generally understood to represent an accurate representation of a patient's disease biology, but can instead reflect a combination of disease biology and the biospecimen's response to a wide range of biological stresses. The molecular signatures of disease can thus be confounded by the signatures of biospecimen biological stress, with the potential to affect clinical and research outcomes through incorrect diagnosis of disease, improper use of a given therapy, and irreproducible research results that can lead to misinterpretation of artifacts as biomarkers. Biospecimen research represents the kind of bricks-and-mortar research that provides a solid scientific foundation for future advances that will directly help patients.

Investigation of drug-induced mitochondrial toxicity using fluorescence-based oxygen-sensitive probes.

Mitochondrial dysfunction is a common mechanism of drug-induced toxicity. Early identification of new chemical entities (NCEs) that perturb mitochondrial function is of significant importance to avoid attrition in later stages of drug development. One of the most informative ways of assessing mitochondrial dysfunction is by measuring mitochondrial oxygen consumption. However, the conventional polarographic method of measuring oxygen consumption is not amenable to high sample throughput or automation. We present an alternative, low-bulk, high-throughput approach to the analysis of isolated-mitochondrial oxygen consumption using luminescent oxygen-sensitive probes. These probes are dispensable and are analyzed in standard microtitre plates on a fluorescence plate reader. Respiratory substrate and adenosine diphosphate (ADP) dependencies of mitochondrial oxygen consumption were assessed using the fluorescence-based method, and results compared favourably to conventional polarographic analysis. To assess assay performance, the method was then applied to the analysis of a panel of classical modulators of oxidative phosphorylation. The effect of uncoupler concentration was analyzed in detail to identify factors which would be important in applying this method to large scale NCE screening and mechanistic investigations. Results demonstrate that the 96-well format can accommodate up to approximately 200 compounds/day at a single concentration or alternatively IC(50) values can be generated for approximately 25 compounds. Throughput may be increased by moving to a 384-well plate format.