Collectively, the presence of the genomic/genetic characteristics of ATM haploinsufficiency or allelic variants, which are a common hallmark of 11q loss, and the loss of functional p53, which is characterized by abnormalities of the p53/MDM2/p14ARF pathway in neuroblastomas, are likely candidates to sensitize PARP inhibitor-induced cytotoxicity by “accelerating” the cell cycle to induce catastrophic cell death (Figure 2). The gene discussed is MDM2; the disease is neuroblastoma.