Project description:The lysine-specific demethylase LSD1/KDM1A is a key regulator of stem cell potential in acute myeloid leukemia (AML). Inhibition of its expression or catalytic activity overcomes the differentiation block and reduces colony formation potential. We have developed ORY-1001 as highly potent and selective inhibitor of KDM1A. Treatment of AML cell lines with ORY-1001 induces accumulation of H3K4me2 marks at KDM1A target genes, compromises leukemic stem cell capacity, and provokes blast differentiation. ORY-1001 exhibits potent synergy with standard of care drugs and with inhibitors of other epigenetic targets; reduces tumor growth and extends survival in mouse xenograft models of acute leukemia. To develop tools for use in clinical trials, we selected a panel of surrogate biomarkers for pharmacodynamic analysis based on expression changes in a panel of 24 leukemia cell lines. ORY-1001/RG6016 was the first selective KDM1A inhibitor to enter the clinic and is currently being evaluated in leukemia and solid tumor clinical trials.
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:Gene expression profiling of immortalized human mesenchymal stem cells with hTERT/E6/E7 transfected MSCs. hTERT may change gene expression in MSCs. Goal was to determine the gene expressions of immortalized MSCs.
