Project description:Leukemia cells instruct their surrounding bone marrow microenvironment (BMM) rendering it hospitable to leukemia cell survival. Conversely, how cells of the BMM influence leukemia progression is less well understood. Pleckstrin homology domain family M member 1 (PLEKHM1) serves as a hub between fusion and secretion of intracellular vesicles. Here, we performed label-free quantitative proteomics to investigate the exosomal cargo released by BMM-derived mesenchymal stromal cells (MSC) lacking Plekhm1 compared to wild-type cells.
Project description:Overexpression and inhibition of miR-29 (pre-miR and anti-miR to miR-29b) in murine aortic smooth muscle cells, analysis of their secretome (conditioned media after serum starvation), n=3 for all four groups (pre-miR control, pre-miR-29b, anti-miR control, anti-miR-29b).
Project description:Primary epithelial cells isolated from fetal lungs of rat fetuses with or without lung hypoplasia induced by the administration of nitrofen to pregnant rats. Control group included epithelial cells from normal fetal lungs. Treatment with amniotic fluid stem cell derived extracellular vesicles or with mesenchymal stromal cell derived exosomes, RNA-seq of both cargos included.
Project description:Tumor progression depends on the bidirectional interactions between cancer and stroma in the heterogenous tumor microenvironment (TME) partially through extracellular vesicles (EVs). However, the secretary mechanism and biological effect of cancer cell derived EVs on tumor survival under starvation is poorly defined. Here, we identify cancer cells preferentially secrete miR-33a in the tumor core region with poor nutrient level. Exosomal miR-33a suppresses putrescine biosynthesis by targeting AGMAT in stromal cells, where putrescine suppresses the expression of demethylase KDM5C. Chromatin immunoprecipitation sequencing identifies miR-33a/KDM5C axis tightly regulates TIA1 gene, functioning stress granule (SG) marker. Exosomal miR-33a diminishes the assembly of stromal SGs but inducing more extracellular matrix accumulation. Collectively, our study reveals tumor selectively secretes miR-33a through EVs to remodel the stromal SG formation and extracellular matrix profiles to gain survival possibility for cancer cells under starvation, highlighting a novel regulatory mechanism of nutrient level on EV secretion and the function of polyamine metabolism in reshaping epigenetic profiles of TME.
Project description:Tissue fibrosis is a significant health issue associated with organ dysfunction and failure. Increased deposition of collagen and other extracellular matrix (ECM) proteins in the interstitial area is a major process in the formation of tissue fibrosis. The microRNA-29 (miR-29) family has been demonstrated as anti-fibrotic microRNAs. Our recent work also showed that dysregulation of miR-29 contributes to the formation of cardiac fibrosis in animal models of uremic cardiomyopathy and replenish of miR-29 attenuated cardiac fibrosis in these animals. However, due to the multi-targeting effect, overexpression of miR-29 could result in unexpected side effect. In the current study, we constructed a novel col1a1-miR-29b vector using collagen 1a1 promoter, which can strategically express miR-29b-3p (miR-29b) in cells with high expression of collagen and thus minimize the side effect of excessive miR-29b. Because of the similarity between the col1a1 promoter in the plasmid and the endogenous col1a1 promoter in the cell, pro-fibrotic factors that stimulate endogenous collagen expression will simultaneously activate the col1a1 promoter in the plasmid vector and thus stimulate the anti-fibrotic miR-29b expression. The increased miR-29b will then contra-regulate the collagen synthesis and maintain a dynamic balance of collagen. To evaluate the anti-fibrotic effect of miR-29b overexpression, we performed RNA sequencing in MEF cells transfected with the col1a1-miR-29b vector with or without TGF-β treatment. A CMV-miR-29b vector was used as positive control. The RNA-sequencing data showed that TGF-β treatment upregulated a broad spectrum of extracellular matrix (ECM) genes. In accordance, the Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis using GAGE package showed that the top 5 upregulated pathways after TGF-β treatment were mostly fibrosis-related, including focal adhesion, ECM reaction, and TGF-β signaling pathways, while transfection of miR-29b expression vectors attenuated the activation of these pathways, suggesting their anti-fibrotic effect. However, despite that the expression of miR-29b in CMV-miR-29b transfected cells were about 1000 times higher compared to the col1a1-miR-29b transfected cells, there was no significant difference in the anti-fibrotic effect in these cells. In summary, our work demonstrated that the col1a1-miR-29b vector expresses much lower miR-29b compared to the CMV-miR-29b vector, but it is as effective as the CMV-miR-29b vector in blocking the fibrosis-related signaling pathways in response to TGF-β treatment. Our results also suggest that miR-29b has a moderate effect on each of its targeting genes, and its anti-fibrotic effect may result from perturbation of a broad spectrum of fibrosis-related signaling pathways.
Project description:Mesenchymal stem cell transplantation (MSCT) has been widely used to treat a variety of human diseases. However, the detailed mechanisms underlying its success are not fully understood. Here we show that MSCT rescues recipient bone marrow mesenchymal stem cell (BMMSC) function in Fas-deficient-MRL/lpr systemic lupus erythematosus (SLE) mice via a miR-29b/Dnmt1/Notch epigenetic cascade. Using the microRNA microarray, we found that MSCT could rescue the high level of miR-29b in the recipient BMMSCs of MRL/lpr mice.
Project description:Dendritic cells (DCs) are among the major components of multiple myeloma (MM)-associated bone-marrow microenvironment and are involved in MM progression, growth and chemo-resistance. We observed that after 24h co-culture with different MM cell lines, DCs downregulate miR-29b expression. To gain insight on the effects of miR-29b, we performed a transcriptome analysis of DCs after transient transfection of a negative control or miR-29b mimics and 24h co-culture with U266 cell line.
