Fig. 7: DT-061 exerts antileukemic activity and reduces N1-ICD expression in the Eµ-TCL1 mouse model of CLL.

A A schematic outline of the treatment schedule is shown. Eμ-TCL1 cells were transplanted into C57BL/6 mice by intravenous (i.v.) injection. Twenty-eight days after transplantation (day 0), treatment started with DT-061 (5 mg/kg once daily for 28 days via oral gavage; n = 3) or vehicle (n = 3). Peripheral blood (PB) was harvested at the start of treatment (day 0), and at day +14 and day +28 from the start of the treatment. At day +28, mice were sacrificed, and spleen and bone marrow were collected. B The bar graphs with data points indicate the percentage of CD19⁺/CD5⁺ cells in PB from DT-061- and vehicle-treated mice, determined by flow cytometry. Data are presented as the mean ± SD of 3 mice per group. ^*P < 0.05 according to unpaired Student’s t-test. C, D The bar graphs with data points indicate the number (left) and the percentage (middle) of CD19⁺/CD5⁺ cells in the spleen (C) and bone marrow (D) from DT-061- and vehicle-treated mice, determined by flow cytometry. Data are presented as the mean ± SD of 3 mice per group.^*P < 0.05; ^***P < 0.001 according to unpaired Student’s t-test. One representative dot plot of CD19/CD5 staining relative to each treatment is shown (right). E, F Left, bar graphs with data points indicate the percentage of viable Annexin V⁻ (An V⁻) cells in CD19⁺/CD5⁺ sorted from the spleen (E) and bone marrow (F) of DT-061- and vehicle-treated mice. Data are presented as the mean ± SD of 3 mice per group. ^*P < 0.05 according to unpaired Student’s t-test. Middle, Western blot analysis of N1-ICD in CD19⁺/CD5⁺ cells sorted from the spleen (E) and bone marrow (F) of DT-061- and vehicle-treated mice performed using the anti-NOTCH1 Val1744 antibody. Right, bar graphs with data points of densitometric analysis of N1-ICD are shown. ^*P < 0.05; ^**P < 0.01 according to unpaired Student’s t-test.