MicroRNAs 221 and 222 in the Pathogenesis of Solid Childhood Tumors

MYCN amplification is a common feature of aggressive neuroblastoma. MicroRNAs (miRNA) are a class of short RNAs that repress translation and promote mRNA degradation by sequence-specific interaction with target mRNAs. Previous studies have associated high expression of the co-regulated miR-221 and miR-222 with progression of various cancer entities. We identified miR-221 to be induced by MYCN in vitro and to correlate with MYCN amplification in primary neuroblastomas. Therefore, we aimed to analyze the effect of manipulating mir221/222-expression in vivo using targeted transgenesis in mice. For this purpose, we…