TP53 and neuroblastoma: This is consistent with, and may help to explain why human MYCN amplified and TH-MYCN transgenic mouse neuroblastoma tumors have high levels of apoptosis, and MYCN amplified and Tet21N MYCN+ neuroblastoma cells undergo higher levels of apoptosis in response to chemotherapeutic agents (Fulda et al., 1999, 2000; Paffhausen et al., 2007; Chesler et al., 2008), irradiation (Bell et al., 2006), and MDM2-p53 antagonists (Gamble et al., 2012).