Project description:miRNAs which are differentially expressed upon MYCN overexpression (1h, 4h and 24h after induction) in a neuroblastoma line were detected using deep sequencing.
Project description:To determine the downstream genes regulated by MYCN in RB, MYCN was silenced in Y79 cell line, which expressed hign levels of MYCN, using two lentiviral shRNA constructs targetting MYCN.
Project description:Global miRNAs expression profilling of SK-N-BE(2)-C cells after dsRNA-mediated knockdown of MYCN To identify MYCN-associated miRNAs, we carried out a small RNA-seq on MYCN knockdown in SK-N-BE(2)-C cells to profile the miRNA expression.
Project description:Neuroblastomas are tumors of the developing peripheral sympathetic nervous system, which originates from the neural crest. Twenty percent of neuroblastomas show amplification of the MYCN oncogene, which correlates with poor prognosis. The MYCN transcription factor can activate and repress gene expression. To broaden our insight in the spectrum of genes down-regulated by MYCN, we generated gene expression profiles of the neuroblastoma cell lines SHEP-21N and SKNAS-NmycER, in which MYCN activity can be regulated. In this study, we show that MYCN suppresses the expression of Dickkopf-1 (DKK1) in both cell lines. DKK1 is a potent inhibitor of the wnt/beta-catenin signalling cascade, which is known to function in neural crest cell migration. We generated a DKK1 inducible cell line, IMR32-DKK1, which showed impaired proliferation upon DKK1 expression. Surprisingly, DKK1 expression did not inhibit the canonical wnt/beta-catenin signalling, suggesting a role of DKK1 in an alternative route of the wnt pathway. Gene expression profiling of two IMR32-DKK1 clones showed that only a few genes, amongst which SYNPO2, were up-regulated by DKK1. SYNPO2 encodes an actin-binding protein and was previously found to inhibit proliferation and invasiveness of prostate cancer cells. These results suggest that MYCN might stimulate cell proliferation by inhibiting the expression of DKK1. DKK1 might exert part of its growth suppressive effect by induction of SYNPO2 expression. Keywords: DKK1, MYCN, neuroblastoma, Dickkopf
Project description:miRNA profiling of Jurkat T-ALL cells after knockdown with two control shRNAs and two shRNAs targeting TAL1 to identify miRNAs that are regulated by TAL1
