Project description:Growing evidence shows a strong interplay between post-transcriptional regulation, mediated by miRs and epigenetic regulation. Nevertheless, the number of experimentally validated miRs (called epimiRs) involved in these regulatory circuitries is still very small. Material & methods:We propose a pipeline to prioritize candidate epi-miRs and to identify potential epigenetic interactors of any given miR starting from miR transfection experiment datasets. Results & conclusion: We identified 34 candidate epi-miRs: 19 of them are known epi-miRs, while 15 are new. Moreover, using an in-house generated gene expression dataset, we experimentally proved that a component of the polycomb-repressive complex 2, the histone methyltransferase enhancer of zeste homolog 2 (EZH2), interacts with miR-214, a well-known prometastatic miR in melanoma and breast cancer, highlighting a miR-214-EZH2 regulatory axis potentially relevant in tumor progression.
Project description:We treated horse mammary derived epithelial cells (MDECs) with either a miR-214-3p mimic or a negative mimic control in the presence of the carcinogenic agent DMBA. Over expression of miR-214-3p suppressed cell apoptosis compared to the control, and suggests a potential oncogenic role in breast cancer.
Project description:Mutations of RUNX1 are detected in patients with myelodysplastic syndrome (MDS). In particular, C-terminal truncation mutations lack a transcription regulatory domain and have increased DNA binding through the runt homology domain (RHD). The expression of the RHD, RUNX1(41-214), in mouse hematopoietic cells induced progression to MDS and acute myeloid leukemia (AML). Analysis of pre-myelodysplastic animals revealed expansion of c-Kit+Sca-1+Lin- (KSL) cells and skewed differentiation to myeloid at the expense of the lymphoid lineage. These abnormalities correlate with the phenotype of Runx1-deficient animals, as expected given the reported dominant-negative role of C-terminal mutations over the full-length RUNX1. However, MDS is not observed in Runx1-deficient animals. Gene expression profiling revealed that RUNX1(41-214) KSLs have an overlapping yet distinct gene expression profile from Runx1-deficient animals. Moreover, an unexpected parallel was observed between the hematopoietic phenotype of RUNX1(41-214) and aged animals. Genes deregulated in RUNX1(41-214), but not in Runx1-deficient animals, were inversely correlated with the aging gene signature of hematopoietic stem cells (HSC), suggesting that disruption of the expression of genes related to normal aging by RUNX1 mutations contributes to development of MDS. The data presented here provide insights into the mechanisms of development of MDS in HSCs by C-terminal mutations of RUNX1. Gene expression analysis were performed on c-Kit+/Sca-1+/Lin-/IL7Ra- (KSL) cells sorted from RUNX1(41-214)-expressing and Runx1-knockout (Runx1floxed/floxed MxCre+/-) and control mice (Runx1floxed/floxedMxCre-/-).
Project description:Despite increasing understanding of the prognostic importance of vascular stiffening linked to perivascular fibrosis in hypertension, the molecular and cellular regulation of this process is poorly understood. We aimed to study the functional role of microRNA-214 (miR-214) in the induction of perivascular fibrosis and endothelial dysfunction driving vascular stiffening. Out of 381 miRs screened in the perivascular tissues (PVAT) in response to angiotensin II (Ang II)-mediated hypertension, miR-214 showed the highest induction (8-fold, p<0.01). MiR-214 induction was pronounced in perivascular and circulating T cells, but not in PVAT adipocytes. Global deletion of miR-214-/- prevented Ang II-induced periaortic fibrosis Col1a1, Col3a1, Col5a1 and Tgfb1 expression, hydroxyproline accumulation and vascular stiffening, without difference in blood pressure. Mechanistic studies revealed that miR-214-/- mice were protected against endothelial dysfunction, oxidative stress and increased Nox2, all of which were induced by Ang II in WT mice. Ang II-induced recruitment of T cells into PVAT was abolished in miR-214-/- mice. Adoptive transfer of miR-214-/- T cells into RAG1-/- mice resulted in reduced perivascular fibrosis compared to the effect of WT T cells. Ang II induced hypertension caused significant change in the expression of 1380 T cell genes in WT, but only 51 in miR-214-/-. T cell activation, proliferation and chemotaxis pathways were differentially affected. miR-214-/- prevented Ang II-induction of pro-fibrotic T cell cytokines (IL-17, TNF, IL-9 and IFN) and chemokine receptors (CCR1, CCR2, CCR4, CCR5, CCR6 and CXCR3). This manifested in reduced in vitro and in vivo T cell chemotaxis resulting in attenuation of profibrotic perivascular inflammation. Translationally, we show that miR-214 is increased in plasma of hypertensive patients and is directly correlated to pulse wave velocity as a measure of vascular stiffness.
Project description:Mutations of RUNX1 are detected in patients with myelodysplastic syndrome (MDS). In particular, C-terminal truncation mutations lack a transcription regulatory domain and have increased DNA binding through the runt homology domain (RHD). The expression of the RHD, RUNX1(41-214), in mouse hematopoietic cells induced progression to MDS and acute myeloid leukemia (AML). Analysis of pre-myelodysplastic animals revealed expansion of c-Kit+Sca-1+Lin- (KSL) cells and skewed differentiation to myeloid at the expense of the lymphoid lineage. These abnormalities correlate with the phenotype of Runx1-deficient animals, as expected given the reported dominant-negative role of C-terminal mutations over the full-length RUNX1. However, MDS is not observed in Runx1-deficient animals. Gene expression profiling revealed that RUNX1(41-214) KSLs have an overlapping yet distinct gene expression profile from Runx1-deficient animals. Moreover, an unexpected parallel was observed between the hematopoietic phenotype of RUNX1(41-214) and aged animals. Genes deregulated in RUNX1(41-214), but not in Runx1-deficient animals, were inversely correlated with the aging gene signature of hematopoietic stem cells (HSC), suggesting that disruption of the expression of genes related to normal aging by RUNX1 mutations contributes to development of MDS. The data presented here provide insights into the mechanisms of development of MDS in HSCs by C-terminal mutations of RUNX1.
Project description:The goal of this study was to investigate the effects of miR-138 or miR-181ab1 on regulating osteogenesis. Gene expression profiles were analyzed in human de-differentiated chondrocytes (DDCs) over-expressing either miR-138 or miR-181ab1 following day 2 or day 7 of osteogenic induction. DDCs were isolated from human osteoarthritic articular cartilage and over-expression of miR-138 or miR-181ab1 was induced following lentiviral transduction of DDCs over-expressing the precursor form of miR-138 or miR-181ab1. Control DDCs were transduced with lentivirus expressing a non-silencing (NS) control RNA. Total RNA was harvested at day 2 or day 7 following osteogenic induction and subjected to RNA-Seq analysis.
Project description:Animals were sc dosed with 5mg/kg anti-miR-214 or control anti-miR, had UUO performed and were sacrificed at 7 days. n=4 animals per group, 2 groups