ABT-199 response in human T-ALL cell lines. (A) The effect of 48 hours of ABT-199 treatment on the viability of human T-ALL cell lines relative to cells treated with dimethylsulfoxide (100%). The results represent the average and standard deviation for at least 2 independent experiments. SD, standard deviation. (B) Caspase 3/7 activity was measured 24 hours after adding ABT-199 and was plotted relative to the DMSO control. The average and standard deviation of 3 independent experiments is shown. The caspase activity after treatment with 20 nM of ABT-199 was significantly higher in LOUCY than ALL-SIL (P = .0088; 2-sided t test), PEER (P = .0008; 2-sided t test), or JURKAT (P = .0119; 2-sided t test with Welch's correction). (C) BCL-2 and BCL-2L1 expression measured with quantitative real-time polymerase chain reactions in a panel of T-ALL cell lines. The graph shows the calibrated normalized relative quantities values and corresponding standard error as calculated with qBasePLUS. The gene expression was standardized against HMBS, TBP, and UBC. (D) Correlation between the IC₅₀ values for ABT-199 and BCL-2 mRNA expression in human T-ALL cell lines. (E) Western blot of BCL-2 and BCL-XL in T-ALL cell lines with β-actin as the loading control. (F) Correlation between the IC₅₀ values for ABT-199 and BCL-2 protein levels in human T-ALL cell lines.