MYCN was shown to recruit HDAC1/2/3/5 to promoter sites to repress transcription in neuroblastoma cells,18, 19, 20, 21 whereas HDAC8 and HDAC10 inhibit differentiation and promote autophagy-mediated survival in a MYCN-independent manner.22, 23 Gao et al.24 identified and characterized HDAC11 in 2002, the only class IV HDAC family member identified to date, which is located within the ~25 kb region of chromosome 3p25.1. Here, HDAC9 is linked to neuroblastoma.