l-ase increases GS expression in AML, which may represent a mechanism of resistance tol-ase. (A) MOLM-14, OCI-AML3, and primary AML blast cells from 3 patients were cultured over a 24-hour period with or without 0.1, 1, or 10 UI/mL E colil-ase. GS expression was determined by western blotting. (B) OCI-AML3 and MV4-11 cells were stably infected with a lentiviral vector expressing either a CTR or a GS shRNA and then cultured with or without 10 UI/mL E colil-ase and with or without glutamine at 4 mM for 24 hours. Western blotting was then performed to assess the GS expression level. (C) The same cell lines were tested by flow cytometry analysis of Annexin V fixation for apoptosis induction after 24 hours in the presence or absence of E colil-ase at 10 UI/mL and with or without glutamine starvation.