A recent study reported that the RNF5 pharmacological activator Analog-1 exerts a potent cytotoxic effect against neuroblastoma and melanoma, probably by promoting the degradation of proteins relevant to the growth of these tumors by activating RNF5.17 We thus utilized wild-type cells and cells in which the expression of RNF5 had been silenced by shRNA to test how this agent impacts the stability of E. Analog-1 effectively reduced the stability of E without detectably impacting the protein level of RNF5 (Supplementary Fig. 5a, lanes 1–4). The gene discussed is RNF5; the disease is neuroblastoma.