PT  - JOURNAL ARTICLE
AU  - Daniel J. Urban
AU  - Natalia J. Martinez
AU  - Mindy I. Davis
AU  - Kyle R. Brimacombe
AU  - Dorian M. Cheff
AU  - Tobie D. Lee
AU  - Mark J. Henderson
AU  - Steven A. Titus
AU  - Rajan Pragani
AU  - Jason M. Rohde
AU  - Yuhong Wang
AU  - Surendra Karavadhi
AU  - Pranav Shah
AU  - Olivia W. Lee
AU  - Amy Wang
AU  - Andrew McIver
AU  - Hongchao Zheng
AU  - Xiaodong Wang
AU  - Xin Xu
AU  - Ajit Jadhav
AU  - Anton Simeonov
AU  - Min Shen
AU  - Matthew B. Boxer
AU  - Matthew D. Hall
TI  - Assessing inhibitors of mutant isocitrate dehydrogenase using a suite of pre-clinical discovery assays
AID  - 10.1101/124024
DP  - 2017 Jan 01
TA  - bioRxiv
PG  - 124024
4099  - http://biorxiv.org/content/early/2017/04/07/124024.short
4100  - http://biorxiv.org/content/early/2017/04/07/124024.full
AB  - Isocitrate dehydrogenase 1 and 2 (IDH1 and IDH2) are key metabolic enzymes that are mutated in a variety of cancers to confer a gain-of-function activity resulting in the accumulation and secretion of an oncometabolite, D-2-hydroxyglutarate (2-HG). Accumulation of 2-HG can result in epigenetic dysregulation and a block in cellular differentiation, suggesting these mutations play a role in neoplasia. Based on its potential as a cancer target, a number of small molecule inhibitors have been developed to specifically inhibit mutant forms of IDH (mIDH1 and mIDH2). Here, a panel of mIDH inhibitors were systematically profiled using biochemical, cell-based, and tier-one ADME techniques. We quantified the biochemical effect of each inhibitor on mIDH1 (R132H and R132C) and mIDH2 (R172Q). The effect of these inhibitors on 2-HG concentrations in seven cell lines representing five different IDH1 mutations in both 2D and 3D cell cultures was assessed. Target engagement of these inhibitors was analyzed utilizing cellular thermal shift assays (CETSA), the effects of inhibitors on reversing 2-HG-induced block on leukemic cellular differentiation. We conclude from our mIDH1 assay panel that AG-120 and a Novartis inhibitor exhibited excellent activity in all biochemical and most cellular assays. While AG-120 has superior DMPK properties, it lacks efficacy a leukemic differentiation model. In conclusion, we present a comprehensive suite of in vitro preclinical drug development assays that can be used as a tool-box to identify lead compounds for mIDH drug discovery programs, as well as what we believe is the most comprehensive publically available dataset on the top mIDH inhibitors.