Fig. 2: Pharmacologic GSK3β inhibition enhances N1-ICD stability and CLL cell viability.

A Box and whisker plots with data points of real-time PCR analysis of NOTCH1, HES1 and DELTEX (DTX) mRNA in CLL cells cultured for 3 h with 5 μM SB216763 or DMSO as control (n = 12). mRNA levels were normalized to GAPDH and represented as fold change using control cells as a reference. *P < 0.05; ns, not significant, according to Wilcoxon paired test. B, C After pretreatment with 5 μM SB216763 or DMSO for 1.5 h, CLL cells were treated (T = 0) with 50 μg/ml CHX and harvested at the indicated times for Western blot analysis of N1-ICD and GAPDH, as a loading control (n = 6). B The values under the blots relative to each treatment indicate the fold change in N1-ICD expression at the different time points compared with the respective T = 0 (set to 1), normalized to GAPDH levels. Three CLL samples are shown. C N1-ICD bands were quantified by densitometry analysis, normalized to GAPDH and represented as percentage of T = 0 value set to 100%. Data are presented as the mean ± SD of 6 CLL samples. *P < 0.05 according to Wilcoxon paired test. D CLL cells were cultured for 18 h with 5 μM SB216763 or DMSO as control (n = 8). Cell viability was measured by MTS assay. Box and whisker plots with data points, expressed as optical density (OD) values, are shown. **P < 0.01 according to Wilcoxon paired test.