lncRNA-TINCR Functions as a Competitive Endogenous RNA to Regulate the Migration of Mesenchymal Stem Cells by Sponging miR-761

Recent insights into the microRNA and long non-coding RNA-mediated regulation of stem cell populations

Stem cells are undifferentiated cells that have multi-lineage differentiation. The transition from self-renewal to differentiation requires rapid and extensive gene expression alterations. Since different stem cells exhibit diverse non-coding RNAs (ncRNAs) expression profiles, the critical roles of ncRNAs in stem cell reprogramming, pluripotency maintenance, and differentiation have been widely investigated over the past few years. Hence, in this current review, the two main categories of ncRNAs, microRNAs (miRNAs) and long non-coding RNAs (lncRNAs), are discussed. While the primary way by which miRNAs restrict mRNA transcription is through miRNA-mRNA interaction, lncRNAs have a wide range of effects on mRNA functioning, including interactions with miRNAs. Both of these ncRNAs participate in the post-transcriptional regulation of crucial biological mechanisms, such as cell cycle regulation, apoptosis, aging, and cell fate decisions. These findings shed light on a previously unknown aspect of gene regulation in stem cell fate determination and behavior. Overall, we summarized the key roles of miRNAs (including exosomal miRNAs) and lncRNAs in the regulation of stem cell populations, such as cardiac, hematopoietic, mesenchymal, neural, and spermatogonial, as well ncRNAs' influence on malignancy through modulating cancer stem cells, which might significantly contribute to clinical stem cell therapy and in regenerative medicine.

Identification of novel key regulatory lncRNAs in gastric adenocarcinoma

Background

Stomach adenocarcinoma (STAD) is one of the most common and deadly cancers worldwide. Recent evidence has demonstrated that dysregulation of long noncoding RNAs (lncRNA) is associated with different hallmarks of cancer. lncRNAs also were suggested as novel promising biomarkers for cancer diagnosis and prognosis. Despite these previous investigations, the expression pattern, diagnostic role, and hallmark association of lncRNAs in STAD remain unclear.

Results

In this study, The STAD lncRNA-mRNA network was constructed based on RNAs that differentially expressed among tumor and normal samples and had a strong expression correlation with others. The high degree nodes of the network were associated with overall survival. In addition, we found that the hubs’ regulatory roles have previously been confirmed in different types of cancers by literature. For example, the HCG22 hub inhibited cell proliferation and invasion and induced apoptosis in oral squamous cell carcinoma (OSCC) cells. The levels of PCNA, Vimentin, and Bcl2 were decreased and E-cadherin and Bax expression was elevated in OSCC cells after HCG22 overexpression. Additionally, HCG22 overexpression inhibited the Akt, mTOR, and Wnt/β-catenin pathways.

Then lncRNAs were mapped to their related GO terms and cancer hallmarks. Based on these mappings, we predict the hallmarks that might be associated with each lncRNA. Finally, the literature review confirmed our prediction.

Among the 20 lncRNAs of the STAD network, 11 lncRNAs (LINC02560, SOX21-AS1, C5orf66-AS1, HCG22, PGM5-AS1, NALT1, ENSG00000241224.2, TINCR, MIR205HG, HNF4A-AS1, ENSG00000262756) demonstrated expression correlation with overall survival (OS). Based on expression analysis, survival analysis, hallmark associations, and literature review, LINC02560, SOX21-AS1, C5orf66-AS1, HCG22, PGM5-AS1, NALT1, ENSG00000241224.2, TINCR, MIR205HG, HNF4A-AS1 plays a regulatory role in STAD. For example, our prediction of association between C5orf66-AS1 expression dysregulation and “sustaining proliferative signal” and “Activating invasion and metastasis” has been confirmed in STAD, OSCC and cervical cancer. Finally, we developed a lncRNA signature with SOX21-AS1 and LINC02560, which classified patients into high and low-risk subgroups with significantly different survival outcomes. The mortality rate of the high-risk patients was significantly higher compared to the low-risk patients (28/1% vs 60.13).

Conclusion

These findings help in designing more precise and detailed experimental studies to find STAD biomarkers and therapeutic targets.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12864-022-08578-6.

LncRNA TINCR improves cardiac hypertrophy by regulating the miR-211-3p-VEGFB-SDF-1α-CXCR4 pathway

Cardiac hypertrophy is a common cardiovascular disease that is found worldwide and is characterized by heart enlargement, eventually resulting in heart failure. Exploring the regulatory mechanism of cardiac hypertrophy is beneficial for understanding its pathogenesis and treatment. In our study, we have showed TINCR was downregulated and miR-211-3p was upregulated in TAC- or Ang II-induced models of cardiac hypertrophy. Dual luciferase and RIP assays revealed that TINCR served as a competitive endogenous RNA (ceRNA) for miR-211-3p. Then, we observed that knockdown of miR-211-3p alleviated TAC- or Ang II-induced cardiac hypertrophy both in vivo and in vitro. Mechanistically, we demonstrated that miR-211-3p directly targeted VEGFB and thus regulated the expression of SDF-1α and CXCR4. Rescue assays further confirmed that TINCR suppressed the progression of cardiac hypertrophy by competitively binding to miR-211-3p, thereby enhancing the expression of VEGFB and activating the VEGFB-SDF-1α- CXCR4 signal. Furthermore, overexpression of TINCR suppressed TAC-induced cardiac hypertrophy in vivo by targeting miR-211-3p-VEGFB-SDF-1α- CXCR4 signalling. In conclusion, our research suggests that LncRNA TINCR improves cardiac hypertrophy by targeting miR-211-3p, thus relieving its suppressive effects on the VEGFB-SDF-1α-CXCR4 signalling axis. TINCR and miR-211-3p might act as therapeutic targets for the treatment of cardiac hypertrophy.

Identification and Functional Analysis of lncRNAs Responsive to Hypoxia in Eospalax fontanierii

Subterranean rodents could maintain their normal activities in hypoxic environments underground. Eospalax fontanierii, as one kind of subterranean rodent found in China can survive very low oxygen concentration in labs. It has been demonstrated that long non-coding RNAs (lncRNAs) have important roles in gene expression regulations at different levels and some lncRNAs were found as hypoxia-regulated lncRNAs in cancers. We predicted thousands of lncRNAs in the liver and heart tissues by analyzing RNA-Seq data in Eospalax fontanierii. Those lncRNAs often have shorter lengths, lower expression levels, and lower GC contents than mRNAs. Majors of lncRNAs have expression peaks in hypoxia conditions. We found 1128 DE-lncRNAs (differential expressed lncRNAs) responding to hypoxia. To search the miRNA regulation network for lncRNAs, we predicted 471 and 92 DE-lncRNAs acting as potential miRNA target and target mimics, respectively. We also predicted the functions of DE-lncRNAs based on the co-expression networks of lncRNA-mRNA. The DE-lncRNAs participated in the functions of biological regulation, signaling, development, oxoacid metabolic process, lipid metabolic/biosynthetic process, and catalytic activity. As the first study of lncRNAs in Eospalax fontanierii, our results show that lncRNAs are popular in transcriptome widely and can participate in multiple biological processes in hypoxia responses.

Mesenchymal Stem Cells for Neurological Disorders

Neurological disorders are becoming a growing burden as society ages, and there is a compelling need to address this spiraling problem. Stem cell-based regenerative medicine is becoming an increasingly attractive approach to designing therapies for such disorders. The unique characteristics of mesenchymal stem cells (MSCs) make them among the most sought after cell sources. Researchers have extensively studied the modulatory properties of MSCs and their engineering, labeling, and delivery methods to the brain. The first part of this review provides an overview of studies on the application of MSCs to various neurological diseases, including stroke, traumatic brain injury, spinal cord injury, multiple sclerosis, amyotrophic lateral sclerosis, Alzheimer's disease, Huntington's disease, Parkinson's disease, and other less frequently studied clinical entities. In the second part, stem cell delivery to the brain is focused. This fundamental but still understudied problem needs to be overcome to apply stem cells to brain diseases successfully. Here the value of cell engineering is also emphasized to facilitate MSC diapedesis, migration, and homing to brain areas affected by the disease to implement precision medicine paradigms into stem cell-based therapies.

Imbalance of Molecular Module of TINCR-miR-761 Promotes the Metastatic Potential of Early Triple Negative Breast Cancer and Partially Offsets the Anti-Tumor Activity of Luteolin

Background

Triple negative breast cancer (TNBC) poses a great threat to patient prognosis. LncRNA-miRNA is a molecular module formed by a long non-coding RNA (LncRNA) and a microRNA (miRNA) that mediates the metastatic potential of tumours such as TNBC, and luteolin (LU) is a natural compound with anti-TNBC activity.

Objective

We aim to explore the regulatory mechanism of terminal differentiation-induced non-coding RNA (TINCR)-miR-761 molecular module in early TNBC, as well as its influence on anti-tumor activity of LU.

Methods

The serum was collected from TNBC patients in early stage to detect the expression of TINCR and miR-761 using RT-PCR. Transwell method was applied for the determination of cell migration and invasion, Western blot for epithelial–mesenchymal transition (EMT), flow cytometry (FCM) for cell apoptosis, and dual luciferase reporter and RNA pull-down experiment for the verification of the targeted relationship between TINCR and miR-761.

Results

Both TINCR and miR-761 were up-regulated in the serum of patients with early TNBC and the area under the curve (AUC) of the two for distinguishing TNBC from BC was not less than 0.850. In the cell function tests, down-regulation of TINCR or miR-761 notably suppressed the metastatic potentials (cell migration, invasion and EMT) of TNBC cells were remarkably inhibited, while up-regulation of TINCR or miR-761 notably promoted the metastatic potentials. We also confirmed that TINCR acts as the molecular sponge of miR-761, and has positive regulation on it. Besides, LU can significantly down-regulate TINCR and miR-761, and partially offset the anti-TNBC activity of LU when they were abnormally up-regulated, which was mainly reflected in the decrease of anti-proliferation and pro-apoptotic ability of LU against TNBC.

Conclusion

There is an imbalance of TINCR-miR-761 molecular module in early TNBC, which may be a potential new therapeutic target of TNBC.

First trimester placental mesenchymal stem cells improve cardiac function of rat after myocardial infarction via enhanced neovascularization

Acute myocardial infarction (AMI) is the most critical heart disease. Mesenchymal stem cells (MSCs) have been widely used as a therapy for AMI for several years. The human placenta has emerged as a valuable source of transplantable cells of mesenchymal origin that can be used for multiple cytotherapeutic purposes. However, the different abilities of first trimester placental chorion mesenchymal stem cells (FCMSCs) and third trimester placental chorion mesenchymal stem cells (TCMSCs) have not yet been explored. In this study, we aimed to compare the effectiveness of FCMSCs and TCMSCs on the treatment of AMI. FCMSCs and TCMSCs were isolated and characterized, and then they were subjected to in vitro endothelial cell (EC) differentiation induction and tube formation to evaluate angiogenic ability. Moreover, the in vivo effects of FCMSCs and TCMSCs on cardiac improvement were also evaluated in a rat MI model. Both FCSMCs and TCMSCs expressed a series of MSCs surface markers. After differentiation induction, FCMSCs-derived EC (FCMSCs-EC) exhibited morphology that was more similar to that of ECs and had higher CD31 and vWF levels than TCMSCs-EC. Furthermore, tube formation could be achieved by FCMSCs-EC that was significantly better than that of TCMSCs-EC. Especially, FCMSCs-EC expressed higher levels of pro-angiogenesis genes, PDGFD, VEGFA, and TNC, and lower levels of anti-angiogenesis genes, SPRY1 and ANGPTL1. In addition, cardiac improvement, indicated by left ventricular end-diastolic diameter (LVEDd), left ventricular end-systolic diameter (LVEDs), left ventricular ejection fraction (LVEF) and left ventricular shortening fraction (LVSF), could be observed following treatment with FCMSCs, and it was superior to that of TCMSCs and Bone marrow MSCs (BMSCs). FCMSCs exhibited a superior ability to generate EC differentiation, as evidenced by in vitro morphology, angiogenic potential and in vivo cardiac function improvement; further, increased levels of expression of pro-angiogenesis genes may be the mechanism by which this effect occurred.

Role of LncRNAs and CircRNAs in Bone Metabolism and Osteoporosis

Bone is a mechanosensitive organ that provides strength and support. Many bone cells, various pathways, and signaling molecules coordinate bone metabolism and also determine the course of bone diseases, such as osteoporosis, osteonecrosis, osteopenia, etc. Osteoporosis is caused by increased bone resorption and reduced bone formation due to the changes in the level of different proteins and RNAs in osteoclast or/and osteoblasts. The available therapeutic interventions can significantly reduce bone resorption or enhance bone formation, but their prolonged use has deleterious side effects. Therefore, the use of non-coding RNAs as therapeutics has emerged as an interesting field of research. Despite advancements in the molecular field, not much is known about the role of long non-coding RNAs (lncRNAs) and circular RNAs (circRNAs) in bone homeostasis and osteoporosis. Therefore, in this article, we summarize the role of lncRNAs and circRNAs in different bone cells and osteoporosis so that it might help in the development of osteoporotic therapeutics.