Level of Vav3 expression is correlated with cell death of p190-BCR-ABL transduced human CD34⁺ cells. (A) Relative Vav3 mRNA expression was assessed by real-time quantitative RT-PCR. Three different shRNA-containing vectors were lentivirally transduced and different levels of Vav3 gene interference were detected cycle threshold (Ct > 50, undetectable level). (B) Apoptosis as determined by annexin V binding in shRNA-transduced p190-BCR-ABL⁺ human B-cell progenitors (day 15 of culture). ***P < .001 from day 10 onward for shRNA #1 (red symbols and line) and from day 13 onward for shRNA #2 (green symbols and line) and shRNA #3 (blue symbols and line) versus control (ANOVA test). Black symbols and line denote control shRNA values. (C) Representative example of FACS analysis of annexin V binding. Annexin V binding was analyzed on EGFP (shRNA)⁺/EYFP (p190-BCR-ABL)⁺/CD19⁺/CD34⁺ cells.