We have previously shown that isogenic glioblastoma cells expressing IDH1R132H mutant are more sensitive to GLS pharmacological inhibition or GLS gene silencing.11 In addition, GLS pharmacological inhibition preferential inhibits IDH1/2 mutant patient-derived AML cells proliferation in vitro.16 Therefore, we explored the direct effect of 2 glutamine antagonist prodrugs (JAM326 and JHU-083) in genetically diverse cancer cells. The gene discussed is IDH1; the disease is cancer.