Figure 3.

Dasatinib inhibits LCK phosphorylation and downstream TCR signaling and induces cell killing when cotreated with temsirolimus. (A) Schematic of TCR and PI3K/AKT/mTOR signaling pathways along with pathway inhibitors. (B) Western blot analysis of T-ALL cells following drug treatment (dasatinib at 100 nM, temsirolimus at 200 nM) for 30 minutes. Representative blot from 3 biological replicates. (C) Western blot showing expression of total LCK and ZAP70 in Jurkat and MOLT-4 wild-type, LCK-deficient (J.Cam1.6 and MOLT-4 clone 12) and ZAP70-deficient (P116) T-ALL cells. Histone H3 (H3) expression used as loading control. (D) Dose-response curves following single drug and combination therapy in LCK- or ZAP70-deficient cells after 72 hours of treatment assessed by CellTiter-Glo. Error bars ± SEM. n = 3 samples/data point. Not significant (ns) by Student 2-tailed t test.