MYCN and neuroblastoma: Similarly, MYCN also regulates LIN28B expression via interaction with the LIN28B promoter and establishes a direct MYCN-LIN28B regulatory axis through which elevated LIN28B expression levels contribute to NB tumorigenesis via let-7 dependent de-repression of MYCN [20] and feedback loops that regulate the MYCN-LIN28B axis [18,19,20,21] (See LIN28B paragraph) (Figure 4).