Drug discovery and toxicity studies require access to methods and technologies that can provide comprehensive evaluation of the types of cellular impacts caused by anti-cancer compounds. In particular, there is growing emphasis on the study of mitochondrial toxicity at an early phase of compound evaluation and its relations to multiple cell death processes that include apoptotic cell death, caspase-independent death and autophagic processes. The study of oxidative stress and its relation to cell death pathways also provides insights into mechanism of cellular stress. In this study we have used multiparametric assays that correlate changes in mitochondria with different cell health parameters using plate-based microcapillary cytometry on guava easyCyte platforms. Compound screening studies were performed on Jurkats (suspension) and HeLa adherent cell lines using an array of over 80 compounds to study inter-relationships between mitochondrial perturbations and different cell health parameters. Compounds were evaluated for mitochondrial depolarization and relationship to apoptosis and cell death; mitochondrial perturbations with regard to caspase levels were also evaluated; and the parallel connection between mitochondrial superoxide stress and apoptosis was also studied. Our studies identified several hit compounds, examples of which included compounds like gambogic acid, thimerosal, camtothecin, antimycin A, staurosporine, celastrol and juglone which caused significant mitochondrial perturbation and apoptosis. In addition, compounds such as antimycin A and staurosporine caused significant oxidative stress. Simplified and rapid screening assays that provide information on multiple parameters of cellular stress and apoptosis can greatly benefit the identification of hit compounds and provide a more comprehensive understanding of the mechanism of compound toxicity.

Citation Format: Katherine Gillis, Julie Clor, Kimvan Tran, Asima Khan, Kamala Tyagarajan. Multiparametric approaches to evaluate mitochondrial toxicity, oxidative stress and apoptosis in drug discovery studies. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 1738. doi:10.1158/1538-7445.AM2013-1738