In this study, we have shown that HDAC2 suppresses TP53INP1 expression and consequently reduces p53 protein phosphorylation at Ser-46, that up-regulation of HDAC2 protects p53 wild type neuroblastoma cells against apoptosis, and that apoptosis due to loss of HDAC2 expression can be blocked by simultaneous depletion of TP53INP1 from the cell. The gene discussed is HDAC2; the disease is neuroblastoma.