Finally, Okabe-Kado et al [75] examined serum NME1 protein levels in 217 patients with neuroblastoma, demonstrating that (i) the serum NME1 protein level was higher in neuroblastoma patients than in control children; (ii) patients with MYCN amplification had higher serum NME1 levels than those with a single copy of MYCN. Here, MYCN is linked to neuroblastoma.