MYCN and neuroblastoma: Interestingly, despite functional, transcriptionally active p53, we have previously reported a failure for MYCN amplified neuroblastoma cells to G1 arrest after DNA damage (Tweddle et al., 2001b; Bell et al., 2006) and have recently shown that the outcome of the p53-mediated response to DNA damage in neuroblastoma cell lines is determined by both morphological subtype (neuronal or substrate adherent) and MYCN expression (Carr-Wilkinson et al., 2011).