Fig. 8: USP28 inhibition decreases CLL cell viability and shows additive effect to venetoclax treatment.

A Cell viability analysis by 7-AAD staining of primary CLL cells (n = 12; 7 NOTCH1 WT and 5 NOTCH1 MUT) treated with 10 µM AZ1. Non-viable cells are quantified as the percentage of 7-AAD+ cells in each individual sample. Statistical significance was assessed via unpaired Student’s t test. B Cell viability analysis by ATP quantification (Cell-Titer Glo) of primary CLL cells (n = 30; 17 NOTCH1 WT and 13 NOTCH1 MUT; Supplementary Table 5) treated with DMSO, 10 µM AZ1, 1 µM nirogacestat (Niro) or the combination of AZ1 and nirogacestat for 24 h. Lines depict median and boxes the interquartile range, data points represent single patient samples. Statistical significance was assessed via two-way ANOVA, followed by Tukey’s multiple comparisons test. C Cell viability analysis by ATP quantification (Cell-Titer Glo) of primary CLL cells (n = 15; 10 NOTCH1 WT (4 NICD low, 6 NICD high) and 5 NOTCH1 MUT; Supplementary Table 4) treated with 1 µM ibrutinib (Ibr), 1.25 nm venetoclax (Ven), increasing doses of AZ1 (5 and 10 µM) or the combination of 10 µM AZ1 with ibrutinib or venetoclax for 24 h. Lines depict median and boxes the interquartile range, data points represent single patient samples. Statistical significance was assessed via one-way ANOVA, followed by Tukey’s multiple comparisons test. WT wild type, MUT mutated, Niro nirogacestat, Ibr ibrutinib, Ven venetoclax.