Fig. 4. RBM39 degradation and RNA mis-splicing via aryl sulfonamides is DCAF15 dependent.

a, b KELLY DCAF15^WT or DCAF15^KO cell line treated with aryl sulfonamide indisulam (a) or E7820 (b) for 72 h. Cell growth was measured by SRB assay. n = 3 independent experiments. c Representative images of KELLY DCAF15^WT or DCAF15^KO cells treated with 1.25 μM indisulam or E7820 (IncuCyte, Sartorius) (n = 3 independent experiments). The scale bar is 400 µm. d, e Caspase 3/7 signal following 48 h treatment of indisulam (d) or E7820 (e). Data normalised to cell mass (SRB) (n = 3 independent experiments). f PCR gel depicting exon skipping of CDK4 (exon 2–4) and TRIM27 (exon 6–7) of KELLY DCAF15^WT or DCAF15^KO cells treated with indisulam or E7820. Representative image of n = 3 independent experiments. g Western blot analysis of RBM39, TYMS, CDK4 and β-actin following 24 h treatment of indisulam or E7820 (representative blot of n = 3 independent experiments). h Densitometry of CDK4 protein analysis of (g). Data are presented as mean values ± SD (a, b) or SEM (d, e, h). Statistical significance in (d, e, h) was determined by a two-tailed unpaired t-test. Source data are provided as a Source Data File.