Telaglenastat (CB 839) is a glutaminase 1 (GLS1) inhibitor with selective, reversible, and oral activity. Telaglenastat has antitumor activity and induces cellular autophagy.

endogenous glutaminase (mouse brain):28 nM, Glutaminase:24 nM, CT-26 cells:0.42 μM, TNBC:20-55 nM, H22 cells:> 10 μM, A549 cells:0.026 μM, CAKI-1 cells:0.04 μM, HCC1806 cells:100 nM, MDA-MB-436 cells:0.52 μM, HCC827 cells:51.42 μM, HCT116 cells:0.028 μM, HT1080 cells:44.38 μM, NCI-H358 cells:> 1 μM, NCI-H4 cells:0.036 μM, endogenous glutaminase (mouse kidney):23 nM

Inhibition of CB-839 on rHu-GAC: The enzymatic activity is measured in assay buffer containing 50 mM Tris-Acetate pH 8.6, 150 mM K2HPO4 , 0.25 mM EDTA, 0.1 mg/mL bovine serum albumin, 1 mM DTT, 2 mM NADP+ and 0.01% Triton X-100. To measure inhibition, the inhibitor (prepared in DMSO) is first pre-mixed with glutamine and glutamate dehydrogenase (GDH) and reactions are initiated by the addition of rHu-GAC. Final reactions contains 2 nM rHu-GAC, 10 mM glutamine, 6 units/mL GDH and 2% DMSO. Generation of NADPH is monitored by fluorescence (Ex340/Em460 nm) every minute for 15 minutes on a SpectraMax M5e plate reader. Relative fluorescence units (RFU) are converted to units of NADPH concentration (μM) using a standard curve of NADPH. Each assay plate incorporates control reactions that monitores the conversion of glutamate (1 to 75 μM) plus NADP+ to α-ketoglutarate plus NADPH by GDH. Under these assay conditions, up to 75 μM glutamate is stoichiometrically converts to α-ketoglutarate/NADPH by GDH. Initial reaction velocities are calculated by fitting the first 5 minutes of each progress curve to a straight line. Inhibition curves are fitted to a four-parameter dose response equation of the form: % activity = Bottom + (Top-Bottom)/(1+10^((LogIC50-X)*HillSlope)).

For viability assays, all cell lines are treated with CB-839 at the indicated concentrations for 72 hours and analyzed for antiproliferative effects using Cell Titer Glo.(Only for Reference)