To date, the exact mechanisms underlying resistance to HDACi in neuroblastoma remains largely unknown, although somatic heterozygous mutations in the genes encoding histones H3.1 and H3.3 are observed in pediatric high-grade gliomas (Liu et al., 2014), and truncating mutations of HDAC2 have been attributed to resistance to traditional HDACi in colorectal cancer (Ropero et al., 2006). The gene discussed is HDAC2; the disease is neuroblastoma.