MYCN and neuroblastoma: For the rest eleven miRNAs, as shown in Figure 3D-3F, siRNA knockdown of MYCN expression leads to a significant upregulation of six miRNAs (miR-449b-5p, miR-137, miR-124-3p, miR-34a-5p, miR-449a and miR-506-3p) in at least one of the three neuroblastoma cell lines examined, indicating that N-Myc functions as a repressor of these miRNA expressions.