PLK1 and neuroblastoma: Notably, PLK1 and MYCN can activate each other reciprocally [32], and aurora A stabilizes MYCN through direct binding [33], indicating that pharmacological inhibition of either aurora A, MLN8054, and MLN8237 [33], or PLK1, BI 2536, BI 6727 (vorasercib), and GSK461364 [34,35], could be beneficial for treating MYCN-amplified neuroblastomas (Figure 1).