NPM1 and neuroblastoma: Two different sequences were investigated: the fragment corresponding to the 2nd helix of the C-terminal domain of nucleophosmin 1 (NPM1264–277), encompassing residues 264–277, which is able to form amyloid-like assemblies and fibrils toxic to neuroblastoma cells, and the fragment spanning residues 21–40 of the Aβ amyloid peptide (Aβ21–40).