Project description:In this study, we defined a novel miRNA, hsa-miR-12462, through small RNA sequencing of the bone marrow (BM) cells from 128 newly diagnosed subjects with AML
Project description:We constructed a genome wide target profile of hsa-miR-503, hsa-miR-103, and hsa-miR-494 by sequencing RNA isolated from Ago2 immunoprecipitations and total RNA samples following transfection of the respective miRNA in mature duplex form
Project description:We report the application of transcriptome sequencing for investigating of the hsa-miR-371a-5p and hsa-miR-518a-3p regulated genes. JAR, JEG-3 and BeWo choriocarcinoma cells were transfected with hsa-miR-371a-5p or hsa-miR-518a-3p inhibitors or control inhibitors. Totally, 237, 132 and 277 genes with > 2 folds change and adjusted P < 0.05 were upregulated in JAR, JEG-3 and BeWo cells respectively after hsa-miR-371a-5p knockdown. Meanwhile, 229, 269 and 191 genes were upregulated in JAR, JEG-3 and BeWo cells respectively after hsa-miR-518a-3p knockdown. The top upregulated genes included many oncogenes or oncogenesis associated ones. Enrichment analysis showed hsa-miR-371a-5p and hsa-miR-518a-3p regulated diverse pathways related to tumorigenesis and metastasis. Our results would be helpful for the searching of early molecular biomarkers and therapeutic targets for gestational trophoblastic neoplasia.
Project description:We constructed a genome wide target profile of hsa-miR-503, hsa-miR-103, and hsa-miR-494 by sequencing RNA isolated from Ago2 immunoprecipitations and total RNA samples following transfection of the respective miRNA in mature duplex form Examination of mRNA levels in HeLa cells and Ago2 immunoprecipitations from HeLa cells following miR-503, miR-103, or miR-494 mature duplex or control siRNA transfection
Project description:Specificity of interaction between a microRNA (miRNA) and its targets crucially depends on the seed region located in its 5’-end. It is often implicitly considered that two miRNAs sharing the same biological activity should display similarity beyond the strict six nucleotide region that forms the seed, in order to form specific complexes with the same mRNA targets. We have found that expression of hsa-miR-147b and hsa-miR-210, though triggered by different stimuli (i.e. lipopolysaccharides and hypoxia, respectively), induce very similar cellular effects in term of proliferation, migration and apoptosis. Hsa-miR-147b only shares a “minimal” 6-nucleotides seed sequence with hsa-miR-210, but is identical with hsa-miR-147a over 20 nucleotides, except for one base located in the seed region. Phenotypic changes induced after heterologous expression of miR-147a strikingly differ from those induced by miR-147b or miR-210. In particular, miR-147a behaves as a potent inhibitor of cell proliferation and migration. These data fit well with the gene expression profiles observed for miR-147b and miR-210, which are very similar, and the gene expression profile of miR-147a, which is distinct from the two others. Bioinformatics analysis of all human miRNA sequences indicates multiple cases of miRNAs from distinct families exhibiting the same kind of similarity that would need to be further characterized in terms of putative functional redundancy. Besides, it implies that functional impact of some miRNAs can be masked by robust expression of miRNAs belonging to distinct families. To compare the set of transcripts targeted by hsa-miR-147a, hsa-miR-147b and hsa-miR-210, we overexpressed these miRNAs in human lung adenocarcinoma A549 cells by transfecting them with synthetic pre-miRNAs or a synthetic “negative” pre-miRNA as a control (miR-Neg). RNA samples were harvested at 48 hours post-transfection and 3 independent experiments were carried out. 48 hours post-transfection, 3 independent experiments were performed in dye-swap: hsa-miR-147a versus miR-Neg; hsa-miR-147b versus miR-Neg; hsa-miR-210 versus miR-Neg.
Project description:Myocardial regeneration is restricted to early postnatal life, when mammalian cardiomyocytes still retain the ability to proliferate. The molecular cues that induce cell cycle arrest of neonatal cardiomyocytes towards terminally differentiated adult heart muscle cells remain obscure. We report that the miR-106b~25cluster is higher expressed in the early postnatal myocardium and decreases in expression towards adulthood, especially under conditions of overload, and orchestrates the transition of cardiomyocyte hyperplasia towards cell cycle arrest and hypertrophy by virtue of its targetome. To identify the relevant targets of individual miRNAs in the miR-106b~15 cluster and elucidate the molecular mechanisms underlying the proliferative effects of this microRNA cluster, we assessed the global transcriptomic changes by deep-sequencing total neonatal mouse cardiomyocyte RNA after exogeneous transfection with hsa-miR-106b-5p, hsa-miR-93-5p, hsa-miR-25-3p and compared the transcriptomic profiles to cardiomyocytes transfected with cel-miR-67, a control miRNA.
Project description:Specificity of interaction between a microRNA (miRNA) and its targets crucially depends on the seed region located in its 5’-end. It is often implicitly considered that two miRNAs sharing the same biological activity should display similarity beyond the strict six nucleotide region that forms the seed, in order to form specific complexes with the same mRNA targets. We have found that expression of hsa-miR-147b and hsa-miR-210, though triggered by different stimuli (i.e. lipopolysaccharides and hypoxia, respectively), induce very similar cellular effects in term of proliferation, migration and apoptosis. Hsa-miR-147b only shares a “minimal” 6-nucleotides seed sequence with hsa-miR-210, but is identical with hsa-miR-147a over 20 nucleotides, except for one base located in the seed region. Phenotypic changes induced after heterologous expression of miR-147a strikingly differ from those induced by miR-147b or miR-210. In particular, miR-147a behaves as a potent inhibitor of cell proliferation and migration. These data fit well with the gene expression profiles observed for miR-147b and miR-210, which are very similar, and the gene expression profile of miR-147a, which is distinct from the two others. Bioinformatics analysis of all human miRNA sequences indicates multiple cases of miRNAs from distinct families exhibiting the same kind of similarity that would need to be further characterized in terms of putative functional redundancy. Besides, it implies that functional impact of some miRNAs can be masked by robust expression of miRNAs belonging to distinct families.
Project description:The aim of this small RNA Seq is to determine if the sequence reads observed for hsa-miR-34b-5p and hsa-miR-449c-5p represent library artifacts or sequencing artifacts
Project description:Surface expression of C-X-C chemokine receptor type 4 (CXCR4) in acute myeloid leukemia (AML) has been reported to be an independent prognostic factor for disease relapse and survival. We previously reported that targeting the stromal-derived factor 1M-NM-1 (SDF-1M-NM-1)/CXCR4 axis could overcome resistance of AML cells to chemotherapy both in vitro and in vivo. To further explore the mechanism of targeting CXCR4, in the current study we focused on the regulation of microRNA. Microarray analysis revealed that the hsa-let-7a microRNA was down-regulated in OCI-AML3 cells by SDF-1M-NM-1 treatment and increased after CXCR4 inhibition. To further investigate the role of hsa-let-7a in leukemia biology, we overexpressed it in AML cell lines, which resulted in decreased Bcl-xL protein expression and consequently enhanced cell sensitivity to the chemotherapeutic agent cytarabine, both in vitro and in vivo. We also identified the transcription factor Yin Yang 1 (YY1) as a mediator that links the SDF-1M-NM-1/CXCR4 axis with hsa-let-7a. Western blotting and immunocytochemistry demonstrated a correlation between YY1 and CXCR4 activation. ChIP assay confirmed the binding of YY1 to pri-let-7a DNA fragments. In primary AML samples (n=50), high CXCR4 surface expression was associated with low hsa-let-7a levels (r2=0.53). Improved effects of cytarabine treatment associated with greatly extended survival of human AML carrying mice was observed in primary human AML overexpressing hsa-let-7a. On the basis of these results, we propose that CXCR4 regulation of hsa-let-7a microRNA through YY1 and transcriptional silencing of the Bcl-xL protein together identifies a novel mechanism by which CXCR4 functions to induce chemoresistance in AML cells. MicroRNA expression profiling of OCI-AML3 cell lines treated with CXCR4 antagonist or SDF-1M-NM-1. OCI-AML3 cells were treated with 100 ng/mL SDF-1M-NM-1 or 250 nM POL6326 (a CXCR4 antagonist, Allschwil, Switzerland), total RNA was extracted at specific time points (1, 2, 4, and 8 h), and miRNA expression profiling was performed