Project description:The aim of the study was to identify differentially expressed miRNAs in different Wilms tumor subtypes. Comparison of miRNA expression profiles in Wilms tumor of different subtypes (total n=62) compared to normal kidney tissue (n=4)
Project description:The aim of the study was to identify differentially expressed mRNAs in different Wilms tumor subtypes and correlate them to miRNA expression profiles of the same tumor samples.
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:Abstract: Background: MiRNA signatures in human sera have been reported for various tumor diseases. Here we generated miRNA profiles analyzing 1205 mature miRNA transcripts of serum samples of Wilms tumor patients, taken prior and after chemotherapy according to SIOP protocol 2001. Using a feature subset selection filter approach we identified a minimal number of miRNAs with a maximum contribution for the classification between treated and untreated patients and between patients and controls. Results: Analyzing 1205 mature miRNAs, we separated controls and Wilms tumor patients prior chemotherapy with an accuracy of 0.81. We obtained a similar accuracy (0.82) for the separation between controls and sera of Wilms tumor patients after preoperative chemotherapy. We identified 23 miRNAs that were differentially expressed in both comparisons. Subset selection improved the overall classification accuracy between controls and Wilms tumor patients prior and after chemotherapy to 0.94 and 0.91, respectively. Subset selection also allowed separating between Wilms tumor patients prior and after chemotherapy with an accuracy of 0.98. Conclusion: Our analysis identified serum based miRNA signatures that allowed separating between controls, untreated Wilms tumor patients, and Wilms tumor patients after chemotherapy with high accuracy for each of these comparisons.
Project description:Blood-borne miRNA signatures have recently been reported for various tumor diseases. Here, we compared the miRNA signature in Wilms tumor patients prior to and after preoperative chemotherapy according to the SIOP protocol 2001. We did not find a significant difference between the miRNA signatures of both groups. However, both Wilms tumor patients prior to and after chemotherapy showed a miRNA signature different from that of healthy controls. The signature of Wilms tumor patients prior to chemotherapy showed an accuracy of 97.5% and of patients after chemotherapy an accuracy of 97.0%, each as compared to healthy controls. Our results provide evidence for a blood-borne Wilms tumor miRNA signature largely independent of four weeks preoperative chemotherapy treatment. This project analyzes peripheral blood profiles of Wilms tumor patients and controls in order to detect specific profiles. n=19 normal controls and n=23 Wilms tumor patients were screened for the complete miRNA repertoire. Please note that each miRNA has been measured in seven replicates and the median of the replica has been computed.
Project description:Profiling of adult and pediatric renal tumors reveals that genome wide miRNA expression patterns are unique to each tumor subtypes. Keywords: Disease state analysis Samples from Clear Cell RCC, Papillary RCC, Chromophobe RCC, Oncocytoma, and Wilms Tumor compared to pooled normal kidney samples from these same patients. No technical replicates.