MYCN and neuroblastoma: When grown in culture, the MYCN PTEN+/− neuroblastoma cells consistently showed higher AlamarBlue fluorescence intensity compared to MYCN PTEN+/+ tumor cells, indicating a higher number of viable MYCN PTEN+/− cells (Figure 3C) and supporting a key inhibitory role for PTEN in growth of neuroblastoma cells in vitro.