Extreme Vulnerability of IDH1 Mutant Cancers to NAD+ Depletion

Publication date: 14 December 2015
Source:Cancer Cell, Volume 28, Issue 6
Author(s): Kensuke Tateishi, Hiroaki Wakimoto, A. John Iafrate, Shota Tanaka, Franziska Loebel, Nina Lelic, Dmitri Wiederschain, Olivier Bedel, Gejing Deng, Bailin Zhang, Timothy He, Xu Shi, Robert E. Gerszten, Yiyun Zhang, Jing-Ruey J. Yeh, William T. Curry, Dan Zhao, Sudhandra Sundaram, Fares Nigim, Mara V.A. Koerner, Quan Ho, David E. Fisher, Elisabeth M. Roider, Lajos V. Kemeny, Yardena Samuels, Keith T. Flaherty, Tracy T. Batchelor, Andrew S. Chi, Daniel P. Cahill
Heterozygous mutation of IDH1 in cancers modifies IDH1 enzymatic activity, reprogramming metabolite flux and markedly elevating 2-hydroxyglutarate (2-HG). Here, we found that 2-HG depletion did not inhibit growth of several IDH1 mutant solid cancer types. To identify other metabolic therapeutic targets, we systematically profiled metabolites in endogenous IDH1 mutant cancer cells after mutant IDH1 inhibition and discovered a profound vulnerability to depletion of the coenzyme NAD+. Mutant IDH1 lowered NAD+ levels by downregulating the NAD+ salvage pathway enzyme nicotinate phosphoribosyltransferase (Naprt1), sensitizing to NAD+ depletion via concomitant nicotinamide phosphoribosyltransferase (NAMPT) inhibition. NAD+ depletion activated the intracellular energy sensor AMPK, triggered autophagy, and resulted in cytotoxicity. Thus, we identify NAD+ depletion as a metabolic susceptibility of IDH1 mutant cancers.

Graphical abstract

Teaser

Tateishi et al. find that proliferation of IDH1 mutant solid cancers can be decoupled from 2-hydroxyglutarate levels and identify NAD⁺ depletion as a metabolic susceptibility in these cancers. Mutant IDH1 lowers NAD⁺ levels by downregulating Naprt1. NAD⁺ depletion triggers autophagy and results in cytotoxicity.


from Cancer via ola Kala on Inoreader http://ift.tt/1Za6TfM
via IFTTT