miR-125b regulates chemotaxis and survival of bone marrow derived granulocytes in vitro and in vivo

Comprehensive circRNA Analyses in Human Vertebrae of GIOP and Its Molecular Mechanism

Circular RNAs (circRNAs) are a novel class of noncoding RNAs that play important roles in human diseases. However, the regulation of circRNAs in glucocorticoid-induced osteoporosis (GIOP) has not been reported. In this study, we performed high-throughput sequencing to identify altered circRNAs in the vertebrae from GIOP patients. A total of 65 clinical samples were collected in this study. Bioinformatics algorithms were employed to predict the target relationship between circRNAs and miRNAs and the circRNAs-miRNAs regulatory network. We focused on the top 10 significantly up-/downregulated circRNAs (hsa_circ_0004906, hsa_circ_0001172, hsa_circ_0005778, hsa_circ_0004276, hsa_circ_0005729, hsa_circ_0006173, hsa_circ_0007662, hsa_circ_0001451, hsa_circ_0001564, and hsa_circ_0108735) and measured their expression by qRT-PCR in clinical samples. Bioinformatics analyses demonstrated that 87 miRNAs were predicted in upregulated circRNAs and 104 miRNAs were predicted in downregulated circRNAs. The functional enrichment analysis showed these targeted miRNAs were significantly enriched in bone metabolism-related biological processes and pathways, including the MAPK signaling pathway, positive regulation of the metabolic process and metabolic pathways, etc. Collectively, our study revealed circRNA regulation and circRNAs-miRNAs regulatory network in GIOP for the first time, which provides a new perspective on the molecular mechanism of GIOP and lays a foundation for GIOP treatment.

Serum MicroRNA on inflammation: a literature review of mouse model studies

MicroRNAs (miRNAs) are small non-coding RNA molecules that regulate target gene expression by binding to sequences in messenger RNA processing. Inflammation is a protective reaction from harmful stimuli. MiRNAs can be biomarkers of diseases related to inflammation and are widely expressed in serum. However, overall changes in serum miRNA levels during inflammation have yet to be observed. Here, we selected studies published until 20 January 2020 that examined miRNAs in mouse models of inflammation. Serum microRNA, inflammation, inflammatory and mouse were used as search terms to select articles from PubMed and MEDLINE. Among the articles, sepsis and 18 related miRNAs were mainly examined. Eleven miRNAs were related to brain disease and 10 with fibrosis. Seventeen injury-induced inflammatory disease studies were included, as well as other inflammatory diseases, such as metabolic disease, vascular disease, arthritis, asthma, autoimmune disease, inflammatory bowel disease, and thyroiditis. The data described miRNA-associated downstream pathways associated with inflammation as well as mitochondrial responses, oxidative responses, apoptosis, cell signalling, and cell differentiation. We expect that the data will inform future animal inflammation-related miRNA studies.

Melanoma-Derived Exosomal miR-125b-5p Educates Tumor Associated Macrophages (TAMs) by Targeting Lysosomal Acid Lipase A (LIPA)

Tumor-associated macrophages (TAMs) are the most abundant immune cells in the tumor microenvironment, promoting tumor initiation, growth, progression, metastasis, and immune evasion. Recently it was shown that cancer cell-derived exosomes induce a tumor-promoting phenotype in TAMs. Exosome-loaded proteins, DNA, and RNAs may contribute to the macrophage reprogramming. However, the exact mediators and mechanisms, particularly in melanoma, are not known. In this study we examined the effects of cutaneous melanoma-derived exosomes on macrophage function and the underlying mechanisms. First, we showed that exposure to melanoma exosomes induces a tumor-promoting TAM phenotype in macrophages. Sequencing revealed enrichment for several miRNAs including miR-125b-5p in cutaneous melanoma exosomes. We showed that miR-125b-5p is delivered to macrophages by melanoma exosomes and partially induces the observed tumor-promoting TAM phenotype. Finally, we showed that miR-125b-5p targets the lysosomal acid lipase A (LIPA) in macrophages, which in turn contributes to their phenotype switch and promotes macrophage survival. Thus, our data show for the first time that miR-125b-5p transferred by cutaneous melanoma-derived exosomes induces a tumor-promoting TAM phenotype in macrophages.