CB-839 (Telaglenastat), a potent, reversible, and selective small-molecule inhibitor that targets GLS-1 and has a half-maximal inhibitory concentration (IC50) of 24 nM for recombinant human glutaminase C, has been investigated in solid tumors and in AML, diffuse large B-cell lymphoma, and multiple myeloma cells alone or in combination with other anticancer drugs (10, 11, 20–26). Here, GLS is linked to plasma cell myeloma.