Project description:Array CGH analysis of paired blood and tumor DNA samples from 14 patients with sporadic Wilms tumor. Previously array CGH studies in WT have only been performed in tumor tissue samples. We herein describe a novel set of constitutional abnormalities and point to candidate genes that might be associated with WT development.
Project description:We have sequenced miRNA libraries from human embryonic, neural and foetal mesenchymal stem cells. We report that the majority of miRNA genes encode mature isomers that vary in size by one or more bases at the 3’ and/or 5’ end of the miRNA. Northern blotting for individual miRNAs showed that the proportions of isomiRs expressed by a single miRNA gene often differ between cell and tissue types. IsomiRs were readily co-immunoprecipitated with Argonaute proteins in vivo and were active in luciferase assays, indicating that they are functional. Bioinformatics analysis predicts substantial differences in targeting between miRNAs with minor 5’ differences and in support of this we report that a 5’ isomiR-9-1 gained the ability to inhibit the expression of DNMT3B and NCAM2 but lost the ability to inhibit CDH1 in vitro. This result was confirmed by the use of isomiR-specific sponges. Our analysis of the miRGator database indicates that a small percentage of human miRNA genes express isomiRs as the dominant transcript in certain cell types and analysis of miRBase shows that 5’ isomiRs have replaced canonical miRNAs many times during evolution. This strongly indicates that isomiRs are of functional importance and have contributed to the evolution of miRNA genes
Project description:Array CGH analysis of paired blood and tumor DNA samples from 14 patients with sporadic Wilms tumor. Previously array CGH studies in WT have only been performed in tumor tissue samples. We herein describe a novel set of constitutional abnormalities and point to candidate genes that might be associated with WT development. 28 paired DNA samples of peripheral blood/fresh tumor tissue from 14 patients (10 males, 4 females) with histologically confirmed WT. All tumor samples were collected from primary tumors from patients treated with the same neoadjuvant chemotherapy following the International Society of Paediatric Oncology (SIOP) WT 2001 trial protocol.
