While eIF4E1 was found in all cell lines tested (Supplementary Figure S4A), the expression level of eIF4E3 varied considerably (it was undetectable in the non-tumoural cell lines NIH3T3, MEF and MRC5, but highest in the mouse neuroblastoma cell line N2a) (Supplementary Figure S4B). This evidence concerns the gene EIF4E and neuroblastoma.