MDM2 and neuroblastoma: In summary, we have characterized 10 neuroblastoma cell lines for alterations at the p53/MDM2/p14ARF signaling pathway, finding that no cell line presented MDM2 amplification, p14ARF promoter methylation, p14ARF homozygous deletions, or p14ARF expression, while only one of them had a TP53 point mutation.