Project description:Systemic lupus erythematosus (SLE) damages multiple organs by producing various autoantibodies. Insufficient interleukin-2 (IL-2) production causes decreased regulatory T cells and permits expansion of autoreactive T cells in the development of SLE. We here show that decreased miR-200a-3p causes IL-2 hypoproduction through directly recruiting ZEB1 or ZEB2 and CtBP2 (ZEB1/ZEB2-CtBP2) complex in SLE T cells. First, we performed RNA sequencing with Illumina Hiseq to obtain the candidate miRNAs and mRNAs involved in the pathogenesis of SLE. We found that miR-200a-3p was significantly downregulated, while its putative targets, ZEB2 and CtBP2 were upregulated in CD4+ T cells in MRL/lpr lupus model mice compared with those of C57BL/6J control mice. ZEB1 and ZEB2 compose ZEB family and suppress various genes including IL-2 by recruiting CtBP2. IL-2 plays a critical role in immune tolerance and IL-2 defect has been recognized in SLE pathogenesis. Therefore, we hypothesized that decreased miR-200a-3p cause IL-2 defect through ZEB1/ZEB2-CtBP2 complex in SLE CD4+T cells. Overexpression of miR-200a-3p induced IL-2 production though downregulating ZEB1, ZEB2 and CtBP2 in EL4 cell lines. We further revealed that miR-200a-3p promote IL-2 expression by reducing the bindings of suppressive ZEB1/ZEB2-CtBP2 complex on NRE-A of IL-2 promoter in SLE murine T cells. Interestingly, ZEB1/ZEB2-CtBP2 complex on NRE-A (a negative regulatory element) were significantly upregulated after phorbol-12-myristate-13-acetate and ionomycin (PMA/Iono) stimulation in lupus T cells. Our findings provide a new insight for the epigenetic regulation of IL-2 defect in SLE.
Project description:Oxaliplatin (oxPt) resistance in colorectal cancers (CRC) is a major unsolved problem. Consequently, predictive markers and a better understanding of resistance mechanisms are urgently needed. To investigate if the recently identified predictive miR-625-3p is functionally involved in oxPt resistance, stable and inducible models of miR-625-3p dysregulation were analyzed. Ectopic expression of miR-625-3p in CRC cells led to increased resistance towards oxPt. The mitogen-activated protein kinase (MAPK) kinase 6 (MAP2K6/MKK6) – an activator of p38 MAPK - was identified as a functional target of miR-625-3p, and, in agreement, was down-regulated in patients not responding to oxPt therapy. The miR-625-3p resistance phenotype could be reversed by anti-miR-625-3p treatment and by ectopic expression of a miR-625-3p insensitive MAP2K6 variant. Transcriptome, proteome and phosphoproteome profiles revealed inactivation of MAP2K6-p38 signaling as a possible driving force behind oxPt resistance. We conclude that miR-625-3p induces oxPt resistance by abrogating MAP2K6-p38 regulated apoptosis and cell cycle control networks.
Project description:Three metastatic melanoma cell lines (BD-0548-ME, DP-0574-ME and WP-0614-ME) were transfected with miR precursors: hsa-miR negative control (NC) or hsa-miR-200a-3p precursors (miR-200a). The objective of this experiment was to determine miR-200a targets in metastatic melanoma cell lines. We selected low -miR-200a expression cell lines and then we overexpressed miR-200a or NC. Finally, we compared the metastatic melanoma cell lines with miR-200a overexpression (miR-200a) to the same cell line transfected with the negative control miR (NC).
Project description:Meningiomas, one of the most common human brain tumors, are derived from arachnoidal cells associated with brain meninges, usually benign and frequently associated with neurofibromatosis type 2. Here we define a human meningioma-typical miRNA profile and characterize effects of one down-regulated miRNA, miR-200a, on tumor growth. Elevated levels of miR-200a inhibited meningioma cell growth in culture and in a tumor model in vivo. Up-regulation of miR-200a decreased expression of transcription factors, ZEB1 and SIP1, with consequently increased expression of E-cadherin, an adhesion protein associated with cell differentiation. Down-regulation of miR-200a in meningiomas and arachnoidal cells resulted in increased expression of β -catenin and cyclin D1 involved in cell proliferation. miR-200a was found to directly target β -catenin mRNA, thereby inhibiting its translation and blocking β -catenin-Wnt signaling, frequently involved in cancer. A direct correlation was found between down-regulation of miR-200a and up-regulation of β-catenin in human meningioma samples. Thus, miR-200a appears to act as a multi-functional tumor suppressor miRNA in meningiomas through effects on the E-cadherin and β -catenin-Wnt signaling pathways. This reveals a previously unrecognized signaling cascade involved in meningioma tumor development and highlights a novel molecular interaction between miR-200a and Wnt signaling, thereby providing insights into novel therapies for meningiomas.
Project description:Meningiomas, one of the most common human brain tumors, are derived from arachnoidal cells associated with brain meninges, usually benign and frequently associated with neurofibromatosis type 2. Here we define a human meningioma-typical miRNA profile and characterize effects of one down-regulated miRNA, miR-200a, on tumor growth. Elevated levels of miR-200a inhibited meningioma cell growth in culture and in a tumor model in vivo. Up-regulation of miR-200a decreased expression of transcription factors, ZEB1 and SIP1, with consequently increased expression of E-cadherin, an adhesion protein associated with cell differentiation. Down-regulation of miR-200a in meningiomas and arachnoidal cells resulted in increased expression of β -catenin and cyclin D1 involved in cell proliferation. miR-200a was found to directly target β -catenin mRNA, thereby inhibiting its translation and blocking β -catenin-Wnt signaling, frequently involved in cancer. A direct correlation was found between down-regulation of miR-200a and up-regulation of β-catenin in human meningioma samples. Thus, miR-200a appears to act as a multi-functional tumor suppressor miRNA in meningiomas through effects on the E-cadherin and β -catenin-Wnt signaling pathways. This reveals a previously unrecognized signaling cascade involved in meningioma tumor development and highlights a novel molecular interaction between miR-200a and Wnt signaling, thereby providing insights into novel therapies for meningiomas. 14 meningioma tumor samples were compared to 3 arachnoidal tissue control samples. Two technical replicates were performed for each sample. Normalization and processing included combining the data from technical replicates. The below table contains quantile-normalized data.
Project description:Oxaliplatin (oxPt) resistance in colorectal cancers (CRC) is a major unsolved problem. Consequently, predictive markers and a better understanding of resistance mechanisms are urgently needed. To investigate if the recently identified predictive miR-625-3p is functionally involved in oxPt resistance, stable and inducible models of miR-625-3p dysregulation were analyzed. Ectopic expression of miR-625-3p in CRC cells led to increased resistance towards oxPt. The mitogen-activated protein kinase (MAPK) kinase 6 (MAP2K6/MKK6) – an activator of p38 MAPK - was identified as a functional target of miR-625-3p, and, in agreement, was down-regulated in patients not responding to oxPt therapy. The miR-625-3p resistance phenotype could be reversed by anti-miR-625-3p treatment and by ectopic expression of a miR-625-3p insensitive MAP2K6 variant. Transcriptome, proteome and phosphoproteome profiles revealed inactivation of MAP2K6-p38 signaling as a possible driving force behind oxPt resistance. We conclude that miR-625-3p induces oxPt resistance by abrogating MAP2K6-p38 regulated apoptosis and cell cycle control networks. Experimental design for mass spectrometry SILAC experiments can be found at https://figshare.com/s/8e79f008e0e58ec6efc2 or https://doi.org/10.6084/m9.figshare.4888139
Project description:Hibernating American black bears have significantly different clotting parameters than their active summer counterparts, affording them innate protection against venous thromboembolism (VTE) despite prolonged periods of immobility. Physiologic changes that occur during hibernation are thought to result from differential gene expression, rather than novel genes, and there is increasing evidence miRNAs may play an important role this regulation. We propose that significant differences exist in miRNA expression in the plasma of hibernating black bears compared to their active counter parts (summer), which lead to critical gene regulation responsible for auto-anticoagulation during hibernation. Methods: Blood was collected from 21 American black bears in the Northern Michigan Peninsula in summer 2017 and winter 2018 (11 active, 10 hibernating). Plasma was extracted Results: Fifteen miRNAs were differentially expressed in the plasma of hibernating black bears. Nine miRNAs were significantly downregulated (miR10b-3p, miR-136-3p, miR-181c-5p , miR-200a-3p, miR-200b-5p, miR-200c-3p, miR-320b, miR-320c and miR-320d) and six miRNAs were significantly upregulated (miR-15a-5p, miR-15b-3p, miR-15b-5p, miR-16-5p, miR-92a-3p, miR-150-5p) during hibernation. Twelve miRNAs had no identifiable targets, but miR-200a-3p, miR-200b-5p and miR-200c-3p found to be targets of SERPINC1, the gene responsible for the production of antithrombin (AT). Conclusions: Several miRNAs were differentially expressed in hibernating bears (12). Most importantly miR-200a-3p, miR-200b-5p and miR-200c-3p were all downregulated in hibernation and associated with increased expression of SERPINC1 and production of AT. AT is a powerful anticoagulant and this finding may explain the hibernating black bears ability to achieve auto-anticoagulation and protection from VTE.
Project description:Long non-coding RNAs (lncRNAs) play pivotal roles in diseases such as osteoarthritis (OA). However, knowledge of the biological roles of lncRNAs is limited in OA. We aimed to explore the biological function and molecular mechanism of HOTTIP in chondrogenesis and cartilage degradation. We used the human mesenchymal stem cell (MSC) model of chondrogenesis, in parallel with, tissue biopsies from normal and OA cartilage to detect HOTTIP, CCL3, and miR-455-3p expression in vitro. Biological interactions between HOTTIP and miR-455-3p were determined by RNA silencing and overexpression in vitro. We evaluated the effect of HOTTIP on chondrogenesis and degeneration, and its regulation of miR-455-3p via competing endogenous RNA (ceRNA). Our in vitro ceRNA findings were further confirmed within animal models in vivo. Mechanisms of ceRNAs were determined by bioinformatic analysis, a luciferase reporter system, RNA pull-down, and RNA immunoprecipitation (RIP) assays. We found reduced miR-455-3p expression and significantly upregulated lncRNA HOTTIP and CCL3 expression in OA cartilage tissues and chondrocytes. The expression of HOTTIP and CCL3 was increased in chondrocytes treated with interleukin-1β (IL-1β) in vitro. Knockdown of HOTTIP promoted cartilage-specific gene expression and suppressed CCL3. Conversely, HOTTIP overexpression reduced cartilage-specific genes and increased CCL3. Notably, HOTTIP negatively regulated miR-455-3p and increased CCL3 levels in human primary chondrocytes. Mechanistic investigations indicated that HOTTIP functioned as ceRNA for miR-455-3p enhanced CCL3 expression. Taken together, the ceRNA regulatory network of HOTTIP/miR-455-3p/CCL3 plays a critical role in OA pathogenesis and suggests HOTTIP is a potential target in OA therapy.
Project description:Microglia were derived from iPSCs and treated with mimics and inhibitors of the miRNAs hsa-miR-150-5p, hsa-miR-193a-3p and hsa-miR-19b-3p. RNA-sequencing was then performed to examine the effects of up- and down-regulation of the respective miRNAs.
Project description:Tumor progression is accompanied by an altered myelopoiesis that causes the accumulation of cells inhibiting anti-tumor T lymphocytes. We previously reported that immunosuppressive cells can be generated in vitro from bone marrow cells (BM) after four days GM-CSF and IL-6 treatment. Here, we describe that miR-142-3p down-regulation directs macrophage differentiation and determines the acquisition of their immunosuppressive function in cancer. Enforced miR over-expression impaired monocyte to macrophage transition both in vitro and in vivo. Conversely, forced miR down-regulation promoted the generation of immunosuppressive macrophages even during G-CSF-induced granulocytic differentiation. To identify how miR-142-3p regulates MDSC generation and activity, we analyze the gene expression of BM cultures transfected with either CTRL- or miR 142-3p mimic oligo -transfected before four days GM-CSF and IL-6 treatment. Keywords: Expression profiling by array BM cells were transfected either CTRL- or miR 142-3p mimic oligo before GM-CSF and IL-6 treatment to generate in vitro MDSCs during enforced miR over-expression. A triplicate of each sample was considered.Total RNA from obtained in vitro BM-differentiated MDSCs was isolated by Trizol reagent, and cRNA samples were hybridized to the Affymetrix GeneChip MOE430 2.0.