Knockdown of H19 enhances differentiation capacity to epidermis of parthenogenetic embryonic stem cells

Linc-ROR Promotes Osteogenic Differentiation of Mesenchymal Stem Cells by Functioning as a Competing Endogenous RNA for miR-138 and miR-145

Long noncoding RNAs (lncRNAs), which serve as important and powerful regulators of various biological activities, have gained widespread attention in recent years. Emerging evidence has shown that some lncRNAs play important regulatory roles in osteoblast differentiation of mesenchymal stem cells (MSCs), suggesting a potential therapeutic strategy for bone fracture. As a recently identified lncRNA, linc-ROR was reported to mediate the reprogramming ability of differentiated cells into induced pluripotent stem cells (iPSCs) and human embryonic stem cells (ESCs) self-renewal. However, other functions of linc-ROR remain elusive. In this study, linc-ROR was found to be upregulated during osteogenesis of human bone-marrow-derived MSCs. Ectopic expression of linc-ROR significantly accelerated, whereas knockdown of linc-ROR suppressed, osteoblast differentiation. Using bioinformatic prediction and luciferase reporter assays, we demonstrated that linc-ROR functioned as a microRNA (miRNA) sponge for miR-138 and miR-145, both of which were negative regulators of osteogenesis. Further investigations revealed that linc-ROR antagonized the functions of these two miRNAs and led to the de-repression of their shared target ZEB2, which eventually activated Wnt/β-catenin pathway and hence potentiated osteogenesis. Taken together, linc-ROR modulated osteoblast differentiation by acting as a competing endogenous RNA (ceRNA), which may shed light on the functional characterization of lncRNAs in coordinating osteogenesis.

Identification of differentially expressed lncRNAs involved in transient regeneration of the neonatal C57BL/6J mouse heart by next-generation high-throughput RNA sequencing

Previous studies have shown that mammalian cardiac tissue has a regenerative capacity. Remarkably, neonatal mice can regenerate their cardiac tissue for up to 6 days after birth, but this capacity is lost by day 7. In this study, we aimed to explore the expression pattern of long noncoding RNA (lncRNA) during this period and examine the mechanisms underlying this process. We found that 685 lncRNAs and 1833 mRNAs were differentially expressed at P1 and P7 by the next-generation high-throughput RNA sequencing. The coding genes associated with differentially expressed lncRNAs were mainly involved in metabolic processes and cell proliferation, and also were potentially associated with several key regeneration signalling pathways, including PI3K-Akt, MAPK, Hippo and Wnt. In addition, we identified some correlated targets of highly-dysregulated lncRNAs such as Igfbp3, Trnp1, Itgb6, and Pim3 by the coding-noncoding gene co-expression network. These data may offer a reference resource for further investigation about the mechanisms by which lncRNAs regulate cardiac regeneration.

Association between long non-coding RNAs expression and pathogenesis and progression of gliomas

The incidence rate of gliomas is the highest among primary brain tumors. Although the understanding of the molecular pathology of glioma has improved during the previous two decades, effective therapies are not yet available to treat these tumors. Previous studies have indicated that long non-coding RNAs (lncRNAs) have a close association with glioma, suggesting that lncRNAs may be potential targets for the development of novel treatments for glioma. The present review summarized the latest studies on the dysregulation of lncRNAs in glioma, and discussed their potential use in the diagnosis, prognosis and therapies of glioma. The emergence of lncRNAs has revealed an additional facet to glioma oncogenesis. An improved understanding of their functions is important to advance lncRNA-based diagnosis, prognosis and therapeutic interventions of glioma.

Long noncoding RNAs (LncRNAs) - The dawning of a new treatment for cardiac hypertrophy and heart failure

Long noncoding RNAs (lncRNAs) represent a category of noncoding RNAs with the potential for genetic and epigenetic regulations. As important regulators of gene expression, increasing evidence has proven that lncRNAs play a significant regulatory role in various cardiovascular pathologies. In particular, lncRNAs have been proved to be participating in gene regulatory mechanisms involved in heart growth and development that can be exploited to repair the injured adult heart. Furthermore, lncRNAs have been revealed as possible therapeutic targets for heart failure with different causes and in different stages. In the journey from a healthy heart to heart failure, lncRNAs have been shown to participate in almost every landmark of heart failure pathogenesis including ischemic injury, cardiac hypertrophy, and cardiac fibrosis. Furthermore, the manipulation of lncRNAs palliates the progression of heart failure by attenuating ischemic heart injury, cardiac hypertrophy and cardiac fibrosis, as well as facilitating heart regeneration and therapeutic angiogenesis. This review will highlight recent updates regarding the involvement of lncRNAs in cardiac hypertrophy and heart failure and their potential as novel therapeutic targets. This article is part of a Special Issue entitled: Genetic and epigenetic control of heart failure - edited by Jun Ren & Megan Yingmei Zhang.

Downregulation of long non-coding RNA H19 promotes P19CL6 cells proliferation and inhibits apoptosis during late-stage cardiac differentiation via miR-19b-modulated Sox6

Background

Regulating cardiac differentiation to maintain normal heart development and function is very important. At present, biological functions of H19 in cardiac differentiation is not completely clear.

Methods

To explore the functional effect of H19 during cardiac differentiation. Expression levels of early cardiac-specific markers Nkx-2.5 and GATA4, cardiac contractile protein genes α-MHC and MLC-2v were determined by qRT-PCR and western lot. The levels of lncRNA H19 and miR-19b were detected by qRT-PCR. We further predicted the binding sequence of H19 and miR-19b by online softwares starBase v2.0 and TargetScan. The biological functions of H19 and Sox6 were evaluated by CCK-8 kit, cell cycle and apoptosis assay and caspase-3 activity.

Results

The expression levels of α-MHC, MLC-2v and H19 were upregulated, and miR-19b was downregulated significantly in mouse P19CL6 cells at the late stage of cardiac differentiation. Biological function analysis showed that knockdown of H19 promoted cell proliferation and inhibits cell apoptosis. H19 suppressed miR-19b expression and miR-19b targeted Sox6, which inhibited cell proliferation and promoted apoptosis in P19CL6 cells during late-stage cardiac differentiation. Importantly, Sox6 overexpression could reverse the positive effects of H19 knockdown on P19CL6 cells.

Conclusion

Downregulation of H19 promoted cell proliferation and inhibited cell apoptosis during late-stage cardiac differentiation by regulating the negative role of miR-19b in Sox6 expression, which suggested that the manipulation of H19 expression could serve as a potential strategy for heart disease.

Long noncoding RNAs: Novel molecules in cardiovascular biology, disease and regeneration

Remarkable breakthroughs made in genomic technologies have facilitated the discovery of thousands of novel transcripts that do not template protein synthesis. Numerous RNAs termed as long noncoding RNAs (lncRNAs) generated from this pervasive transcription function vividly in gene regulatory networks and a variety of biological and cellular processes. Here, we make a brief description of the known and putative functions of lncRNAs in cardiovascular biology and disease. The association between lncRNAs and stem cells mediated cardiomyocytes differentiation and neovascularization is discussed then. It will provide a new clue for further studies on these novel molecules in cardiovascular disease and bring bright prospects for their future applications in cardiac regenerative medicine.

Non-coding RNAs in cardiac regeneration

Developing new therapeutic strategies which could enhance cardiomyocyte regenerative capacity is of significant clinical importance. Though promising, methods to promote cardiac regeneration have had limited success due to the weak regenerative capacity of the adult mammalian heart. Non-coding RNAs (ncRNAs), including microRNAs (miRNAs, miRs) and long non-coding RNAs (lncRNAs), are functional RNA molecules without a protein coding function that have been reported to engage in cardiac regeneration and repair. In light of current regenerative strategies, the regulatory effects of ncRNAs can be categorized as follows: cardiac proliferation, cardiac differentiation, cardiac survival and cardiac reprogramming. miR-590, miR-199a, miR-17-92 cluster, miR302-367 cluster and miR-222 have been reported to promote cardiomyocyte proliferation while miR-1 and miR-133 suppress that. miR-499 and miR-1 promote the differentiation of cardiac progenitors into cardiomyocyte while miR-133 and H19 inhibit that. miR-21, miR-24, miR-221, miR-199a and miR-155 improve cardiac survival while miR-34a, miR-1 and miR-320 exhibit opposite effects. miR-1, miR-133, miR-208 and miR-499 are capable of reprogramming fibroblasts to cardiomyocyte-like cells and miR-284, miR-302, miR-93 , miR-106b and lncRNA-ST8SIA3 are able to enhace cardiac reprogramming. Exploring non-coding RNA-based methods to enhance cardiac regeneration would be instrumental for devising new effective therapies against cardiovascular diseases.

Long Non-Coding RNAs: The Key Players in Glioma Pathogenesis

Long non-coding RNAs (LncRNAs) represent a novel class of RNAs with no functional protein-coding ability, yet it has become increasingly clear that interactions between lncRNAs with other molecules are responsible for important gene regulatory functions in various contexts. Given their relatively high expressions in the brain, lncRNAs are now thought to play important roles in normal brain development as well as diverse disease processes including gliomagenesis. Intriguingly, certain lncRNAs are closely associated with the initiation, differentiation, progression, recurrence and stem-like characteristics in glioma, and may therefore be exploited for the purposes of sub-classification, diagnosis and prognosis. LncRNAs may also serve as potential therapeutic targets as well as a novel biomarkers in the treatment of glioma. In this article, the functional aspects of lncRNAs, particularly within the central nervous system (CNS), will be briefly discussed, followed by highlights of the important roles of lncRNAs in mediating critical steps during glioma development. In addition, the key lncRNA players and their possible mechanistic pathways associated with gliomagenesis will be addressed.

Long Non-Coding RNAs Dysregulation and Function in Glioblastoma Stem Cells

Glioblastoma multiforme (GBM), the most common form of primary brain tumor, is highly resistant to current treatment paradigms and has a high rate of recurrence. Recent advances in the field of tumor-initiating cells suggest that glioblastoma stem cells (GSCs) may be responsible for GBM's rapid progression, treatment resistance, tumor recurrence and ultimately poor clinical prognosis. Understanding the biologically significant pathways that mediate GSC-specific characteristics offers promises in the development of novel biomarkers and therapeutics. Long non-coding RNAs (lncRNAs) have been increasingly implicated in the regulation of cancer cell biological behavior through various mechanisms. Initial studies strongly suggested that lncRNA expressions are highly dysregulated in GSCs and may play important roles in determining malignant phenotypes in GBM. Here, we review available evidence on aberrantly expressed lncRNAs identified by high throughput microarray profiling studies in GSCs. We also explore the potential functional pathways by analyzing their interactive proteins and miRNAs, with a view to shed lights on how this novel class of molecular candidates may mediate GSC maintenance and differentiation.

Ascorbic acid improves pluripotency of human parthenogenetic embryonic stem cells through modifying imprinted gene expression in the Dlk1-Dio3 region

Introduction

Human parthenogenetic embryonic stem cells (hpESCs) are generated from artificially activated oocytes, however, the issue of whether hpESCs have equivalent differentiation ability to human fertilized embryonic stem cells remains controversial.

Methods

hpESCs were injected into male severe combined immunodeficiency (SCID) mice and the efficiency of teratoma formation was calculated. Then the gene expression and methylation modification were detected by real time-PCR and bisulfate methods.

Results

Comparison of five hpESCs with different differentiation abilities revealed that levels of paternal genes in the Dlk1-Dio3 region on chromosome 14 in the hpESCs with high differentiation potential are enhanced, but strictly methylated and silenced in the hpESCs with lower differentiation potential. Treatment with ascorbic acid, rescued their ability to support teratoma formation and altered the expression profiles of paternally expressed genes in hpESCs that could not form teratoma easily. No differences in the expression of other imprinting genes were evident between hpESCs with higher and lower differentiation potential, except for those in the Dlk1-Dio3 region.

Conclusions

The Dlk1-Dio3 imprinting gene cluster distinguishes the differentiation ability of hpESCs. Moreover, modification by ascorbic acid may facilitate application of hpESCs to clinical settings in the future by enhancing their pluripotency.

Electronic supplementary material

The online version of this article (doi:10.1186/s13287-015-0054-9) contains supplementary material, which is available to authorized users.

Enrichment of Human Stem-Like Prostate Cells with s-SHIP Promoter Activity Uncovers a Role in Stemness for the Long Noncoding RNA H19

Understanding normal and cancer stem cells should provide insights into the origin of prostate cancer and their mechanisms of resistance to current treatment strategies. In this study, we isolated and characterized stem-like cells present in the immortalized human prostate cell line, RWPE-1. We used a reporter system with green fluorescent protein (GFP) driven by the promoter of s-SHIP (for stem-SH2-domain-containing 5'-inositol phosphatase) whose stem cell-specific expression has been previously shown. We observed that s-SHIP-GFP-expressing RWPE-1 cells showed stem cell characteristics such as increased expression of stem cell surface markers (CD44, CD166, TROP2) and pluripotency transcription factors (Oct4, Sox2), and enhanced sphere-forming capacity and resistance to arsenite-induced cell death. Concomitant increased expression of the long noncoding RNA H19 was observed, which prompted us to investigate a putative role in stemness for this oncofetal gene. Targeted suppression of H19 with siRNA decreased Oct4 and Sox2 gene expression and colony-forming potential in RWPE-1 cells. Conversely, overexpression of H19 significantly increased gene expression of these two transcription factors and the sphere-forming capacity of RWPE-1 cells. Analysis of H19 expression in various prostate and mammary human cell lines revealed similarities with Sox2 expression, suggesting that a functional relationship may exist between H19 and Sox2. Collectively, we provide the first evidence that s-SHIP-GFP promoter reporter offers a unique marker for the enrichment of human stem-like cell populations and highlight a role in stemness for the long noncoding RNA H19.