ASCL1 and neuroblastoma: To probe the role of endogenous ASCL1 in maintaining the proliferating adrenergic phenotype of neuroblastoma cells, we investigated the effect of ASCL1 deletion in two neuroblastoma lines; the MYCN-amplified IMR32 cell line and the non-MYCN amplified SH-SY5Y cell line, which both express similar levels of ASCL1 (Supplementary Figure S1A).