MYC and neuroblastoma: Therefore, ALK-wt overexpression and activating ALK mutants may not only upregulate MYCN mRNA expression, as shown in neuronal and NB cells [243], but also cooperate with MYCN in NB tumorigenesis [184,243,244,245,247] and they may also upregulate and cooperate with Myc, as observed in murine NCPC [246].