MYCN and neuroblastoma: However, despite MYCN being known to be important in proliferation of mesenchymal progenitor cells during nephrogenesis [16] and an established oncogenic transcription factor of developmental cancers such as medulloblastoma and neuroblastoma (NB) [17], virtually nothing is known about the biological activities of MYCN in WT, including protein expression patterns, downstream transcriptional targets, and possible pathways regulated.