Kar resistance elicits an unforeseen metabolic vulnerability in MM cells. (A) qPCR analysis of the indicated genes in AMO-1 cells was performed by comparing isogenic wild-type (Kar/S) and Kar-resistant (Kar/R) cells. (B) Violin plot representing GLS1 expression level in tumor cells derived from NDMM (Kar/S) and RRMM (Kar/R) patients. (C) Dose-response curves of AMO-1 Kar/S and Kar/R cells to increasing doses of Erw-ASNase (0.1-0.5 U/mL for 48 hours). All data are mean ± SD of 3 independent experiments. **P < .01, ***P < .001, Student t test.