MicroRNA-125b-2 overexpression represses ectodermal differentiation of mouse embryonic stem cells

Gene Expression Studies in Down Syndrome: What Do They Tell Us about Disease Phenotypes?

Down syndrome is a well-studied aneuploidy condition in humans, which is associated with various disease phenotypes including cardiovascular, neurological, haematological and immunological disease processes. This review paper aims to discuss the research conducted on gene expression studies during fetal development. A descriptive review was conducted, encompassing all papers published on the PubMed database between September 1960 and September 2022. We found that in amniotic fluid, certain genes such as COL6A1 and DSCR1 were found to be affected, resulting in phenotypical craniofacial changes. Additionally, other genes such as GSTT1, CLIC6, ITGB2, C21orf67, C21orf86 and RUNX1 were also identified to be affected in the amniotic fluid. In the placenta, dysregulation of genes like MEST, SNF1LK and LOX was observed, which in turn affected nervous system development. In the brain, dysregulation of genes DYRK1A, DNMT3L, DNMT3B, TBX1, olig2 and AQP4 has been shown to contribute to intellectual disability. In the cardiac tissues, dysregulated expression of genes GART, ETS2 and ERG was found to cause abnormalities. Furthermore, dysregulation of XIST, RUNX1, SON, ERG and STAT1 was observed, contributing to myeloproliferative disorders. Understanding the differential expression of genes provides insights into the genetic consequences of DS. A better understanding of these processes could potentially pave the way for the development of genetic and pharmacological therapies.

Mir125b-2 imprinted in human but not mouse brain regulates hippocampal function and circuit in mice

Genomic imprinting predominantly occurs in the placenta and brain. Few imprinted microRNAs have been identified in the brain, and their functional roles in the brain are not clear. Here we show paternal, but not maternal, expression of MIR125B2 in human but not mouse brain. Moreover, Mir125b-2^m-/p- mice showed impaired learning and memory, and anxiety, whose functions were hippocampus-dependent. Hippocampal granule cells from Mir125b-2^m-/p- mice displayed increased neuronal excitability, increased excitatory synaptic transmission, and decreased inhibitory synaptic transmission. Glutamate ionotropic receptor NMDA type subunit 2A (Grin2a), a key regulator of synaptic plasticity, was physically bound by miR-125b-2 and upregulated in the hippocampus of Mir125b-2^m-/p- mice. Taken together, our findings demonstrate MIR125B2 imprinted in human but not mouse brain, mediated learning, memory, and anxiety, regulated excitability and synaptic transmission in hippocampal granule cells, and affected hippocampal expression of Grin2a. Our work provides functional mechanisms of a species-specific imprinted microRNA in the brain.

Characterization of Dental Pulp Stem Cell Populations in the Teeth of Patients With Neurofibromatosis Type 1 - Therapeutic Potential for Bone Tissue Engineering

BACKGROUND/AIM

Neurofibromas (NF) are the most common benign nerve sheath tumors in the tongue, gingiva, major salivary glands, and jaw bones. Nowadays, tissue engineering is a revolutionary technique for reconstructing tissues. To explore the feasibility of using stem cells derived from NF teeth to treat orofacial bone defects, the differences in cell biological properties between an NF teeth group and Normal teeth group.

PATIENTS AND METHODS

The intra-dental pulp tissues from each tooth were extracted. The cell survival rates, morphology, proliferation rates, cell activity, and differentiation abilities were contrastively analyzed between the NF teeth group and Normal teeth group.

RESULTS

Between the two groups, there were no differences in the primary generation (P0) cells (p>0.05), the cell yield, and the time required for the cells to grow out of the pulp tissue and attach to the culture plate. Furthermore, no differences were found at the first generation (passage) between the two groups in colony formation rate and cell survival rate. The proliferation capacity, cell growth curve, and surface marker expression of dental pulp cells was not altered in the third generation (p>0.05).

CONCLUSION

Dental pulp stem cells from NF teeth were successfully obtained and were not different from normal dental pulp stem cells. Although, clinical research using tissue-engineered bone to repair bone defects is still in its infancy, it will eventually enter the clinic and become a routine means of bone defect reconstruction treatment as related disciplines and technologies develop.

MiR-125 Family in Cardiovascular and Cerebrovascular Diseases

Cardiovascular and cerebrovascular diseases are a serious threaten to the health of modern people. Understanding the mechanism of occurrence and development of cardiovascular and cerebrovascular diseases, as well as reasonable prevention and treatment of them, is a huge challenge that we are currently facing. The miR-125 family consists of hsa-miR-125a, hsa-miR-125b-1 and hsa-miR-125b-2. It is a kind of miRNA family that is highly conserved among different species. A large amount of literature shows that the lack of miR-125 can cause abnormal development of the cardiovascular system in the embryonic period. At the same time, the miR-125 family participates in the occurrence and development of a variety of cardiovascular and cerebrovascular diseases, including myocardial ischemia, atherosclerosis, ischemia-reperfusion injury, ischemic stroke, and heart failure directly or indirectly. In this article, we summarized the role of the miR-125 family in the development and maturation of cardiovascular system, the occurrence and development of cardiovascular and cerebrovascular diseases, and its important value in the current fiery stem cell therapy. In addition, we presented this in the form of table and diagrams. We also discussed the difficulties and challenges faced by the miR-125 family in clinical applications.

Retinoic acid and microRNA

Retinoic acid (RA), the biologically active metabolite of vitamin A, regulates a vast spectrum of biological processes, such as cell differentiation, proliferation, apoptosis, and morphogenesis. microRNAs (miRNAs) play a crucial role in regulating gene expression by binding to messenger RNA (mRNA) which leads to mRNA degradation and/or translational repression. Like RA, miRNAs regulate multiple biological processes, including proliferation, differentiation, apoptosis, neurogenesis, tumorigenesis, and immunity. In fact, RA regulates the expression of many miRNAs to exert its biological functions. miRNA and RA regulatory networks have been studied in recent years. In this manuscript, we summarize literature that highlights the impact of miRNAs in RA-regulated molecular networks included in the PubMed.

MicroRNA and retinoic acid

BACKGROUND AND OBJECTIVE

Retinoic acid is a metabolite of vitamin A that is necessary to maintain health in human and most of the other vertebrates. MicroRNAs (miR or miRNAs) are small, non-coding RNA particles that diminish mRNA translation of various genes and so can regulate critical cell processes including cell death, proliferation, development, etc. The aim of this review is to study interrelations between retinoic acid with miRNAs.

METHODS

We reviewed and summarized all published articles in PubMed, Europe PMC, and Embase databases with any relationship between retinoic acid and miRNAs from Jun 2003 to Dec 2018 that includes 126 articles.

RESULTS

Results showed direct and indirect relationships between retinoic acid and miRNAs in various levels including effects of retinoic acid on expression of various miRNAs and miRNA-biogenesis enzymes, and effect of miRNAs on metabolism of retinoic acid.

DISCUTION AND CONCLUSION

This review indicates that retinoic acid has inter-correlations with various miRNA members and their metabolism in health and disease may require implications of the other.

A miR-125b/CSF1-CX3CL1/tumor-associated macrophage recruitment axis controls testicular germ cell tumor growth

Tumor growth is modulated by crosstalk between cancer cells and the tumor microenvironment. Recent advances have shown that miRNA dysfunction in tumor cells can modulate the tumor microenvironment to indirectly determine their progression. However, this process is poorly understood in testicular germ cell tumors (TGCTs). We reported here that miR-125b was repressed in TGCT samples by epigenetic modifications rather than genetic alternations. Furthermore, miR-125b overexpression significantly alleviated the tumor growth in two NCCIT human embryonic carcinoma xenograft models in vivo, whereas miR-125b did not stimulate autonomous tumor cell growth in vitro. Notably, forced expression of miR-125b in NCCIT embryonic carcinoma cells decreased the abundance of host tumor-associated macrophages (TAMs) within tumor microenvironment. Selective deletion of host macrophages by clodronate abolished the anti-tumoral ability of miR-125b in xenograft models. By RNA profiling, Western blot and luciferase reporter assay, we further observed that miR-125b directly regulated tumor cell-derived chemokine CSF1 and CX3CL1, which are known to control the recruitment of TAMs to tumor sites. Lastly, we found that one set of miRNAs, which are under the regulation of miR-125b, might convergently target CSF1/CX3CL1 in NCCIT cells using miRNA profiling. These findings uncover the anticancer effect of miR-125b via mediating tumor-stroma crosstalk in xenograft models of TGCTs and raise the possibility of targeting miR-125b as miRNA therapeutics.

Roles of microRNAs in mammalian reproduction: from the commitment of germ cells to peri-implantation embryos

MicroRNAs (miRNAs) are active regulators of numerous biological and physiological processes including most of the events of mammalian reproduction. Understanding the biological functions of miRNAs in the context of mammalian reproduction will allow a better and comparative understanding of fertility and sterility in male and female mammals. Herein, we summarize recent progress in miRNA‐mediated regulation of mammalian reproduction and highlight the significance of miRNAs in different aspects of mammalian reproduction including the biogenesis of germ cells, the functionality of reproductive organs, and the development of early embryos. Furthermore, we focus on the gene expression regulatory feedback loops involving hormones and miRNA expression to increase our understanding of germ cell commitment and the functioning of reproductive organs. Finally, we discuss the influence of miRNAs on male and female reproductive failure, and provide perspectives for future studies on this topic.

The expression and functional roles of microRNAs in stem cell differentiation

microRNAs (miRNAs) are key regulators of cell state transition and retention during stem cell proliferation and differentiation by post-transcriptionally downregulating hundreds of conserved target genes via seed-pairing in their 3' untranslated region. In embryonic and adult stem cells, dozens of miRNAs that elaborately control stem cell processes by modulating the transcriptomic context therein have been identified. Some miRNAs accelerate the change of cell state into progenitor cell lineages-such as myoblast, myeloid or lymphoid progenitors, and neuro precursor stem cells-and other miRNAs decelerate the change but induce proliferative activity, resulting in cell state retention. This cell state choice can be controlled by endogenously or exogenously changing miRNA levels or by including or excluding target sites. This control of miRNA-mediated gene regulation could improve our understanding of stem cell biology and facilitate their development as therapeutic tools.

Tumor suppressor miR-149-5p is associated with cellular migration, proliferation and apoptosis in renal cell carcinoma

Several studies have recently explored the role of microRNAs (miRNAs, miRs) in the tumorigenesis of various types of cancer. miRNAs have been reported to be involved in numerous cell processes, including cell apoptosis, proliferation and migration, thus suggesting that miRNAs may have an important role in cancer progression. Downregulation of miR-149-5p has been detected in RCC tissues by microarray profiling; however, its expression and function in RCC has yet to be elucidated. In the present study, reverse transcription‑quantitative polymerase chain reaction was performed to detect the expression levels of miR‑149‑5p in RCC tissues and paired normal tissues. In order to determine whether miR-149-5p was able to regulate cell proliferation, apoptosis or migration, 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide, flow cytometric and wound healing assays were conducted. The results demonstrated that miR‑149‑5p was significantly downregulated in RCC tissues compared with in normal tissues (P<0.05). The restoration of miR-149-5p expression using synthetic mimics suppressed cell proliferation and migration, and promoted cell apoptosis. These results indicated that miR‑149‑5p may act as a tumor suppressor in RCC. The present study is the first, to the best of our knowledge, to identify miR‑149‑5p as a tumor suppressor in RCC. Future studies will be focused on the potential role of miR‑149‑5p as a biomarker for the early detection and prognostic prediction of RCC, and as a therapeutic target in RCC. In addition, further exploration regarding the pathways underlying the effects of miR‑149‑5p in RCC is required.