Figure 6.

Combination of dasatinib and temsirolimus inhibit Jurkat T-ALL growth in mouse xenografts. (A) Schematic of experimental design. (B) Representative images of NSG mice engrafted with luciferase+/dsRED2+ Jurkat cells prior to the first day of treatment (day 0) or imaged after treatment on the days noted within each image panel. (C) Kaplan-Meier survival curves. Combination treated mice had significant survival benefit compared with nontreated or monotherapy-treated mice (∗P < .05; ∗∗P < .01, log-rank, Mantel-Cox test). (D) Average radiance of each individual mice measured by bioluminescence. Squares denote the last radiance measurement of moribund animals. Two of 6 combination-treated mice had undetectable leukemia burden at 60 days. ∗P < .05; ∗∗∗P < .001; by Tukey’s post hoc analysis. (E) Quantification of dsRed+ T-ALL cells by flow cytometry analysis of the spleen, bone marrow (BM), and peripheral blood from engrafted mice. Error bars equal ± SEM. ∗P < .05; ∗∗P < .01 by Tukey’s post hoc analysis. (F) Histopathologic analysis of spleens from control and combination therapy-treated mice. Hematoxylin and eosin (H&E), TUNEL, and co-immunohistochemistry for human CD45 (hCD45, FITC) along with either phospho-LCK or phospho-S6K (Alexa Fluor^–594) and DAPI (blue). Scale bars equal 20 μm. Arrows show representative stained cells. (G) Quantification of IHC analysis of spleens denoting the total number of hCD45 T-ALL cells/3 mm² across replicates (i) and TUNEL (ii). The average percentage of positive cells ± SEM is noted. (H) Quantification of phospho-LCK or phospho-S6K staining in CD45⁺ T-ALL cells found in the spleen based on IHC staining. Average intensity is denoted by black bars quantified across >3 animals per condition and 3 sections per spleen. More than 3000 cells were analyzed per condition (G-H). ∗∗P < .01; ∗∗∗∗P < .0001 by Student 2-tailed t test (G-H).