To study the essentiality of DCAF15 in the mode of action of aryl sulfonamides in neuroblastoma, we generated DCAF15 knockout cells using CRISPR–Cas9 in KELLY (Supplementary Fig. 7) in which loss of DCAF15 rescued acute RBM39 degradation from indisulam treatment (6 h, 10 μM, Supplementary Fig. 8). This evidence concerns the gene DCAF15 and neuroblastoma.