DKK2 and neoplasm: In contrast to primary masses, which had a robust adrenergic signature and harbored predominantly neuroblast-like clusters, metastatic sites had diverse malignant populations including neural-crest neuroblast (Nbt) progenitors (TENM2, FGF13, DSCAM27), mesenchymal neural-crest-like tumor cells (MES-Nbt; EYA1, PTN, PDE3A28,29), and their cycling counterparts (TOP2A, MKI6, HMGB2), as well as a discrete DKK2+ Nbt metastatic phenotype (DKK2+ NB Met; VCAN, FUT9, DCC, DKK221,22,23) (Fig. 2A–E and Supplementary Fig. S3).