The long noncoding RNA TUG1 regulates blood-tumor barrier permeability by targeting miR-144

Engineering extracellular vesicles to transiently permeabilize the blood-brain barrier

BACKGROUND

Drug delivery to the brain is challenging due to the restrict permeability of the blood brain barrier (BBB). Recent studies indicate that BBB permeability increases over time during physiological aging likely due to factors (including extracellular vesicles (EVs)) that exist in the bloodstream. Therefore, inspiration can be taken from aging to develop new strategies for the transient opening of the BBB for drug delivery to the brain.

RESULTS

Here, we evaluated the impact of small EVs (sEVs) enriched with microRNAs (miRNAs) overexpressed during aging, with the capacity to interfere transiently with the BBB. Initially, we investigated whether the miRNAs were overexpressed in sEVs collected from plasma of aged individuals. Next, we evaluated the opening properties of the miRNA-enriched sEVs in a static or dynamic (under flow) human in vitro BBB model. Our results showed that miR-383-3p-enriched sEVs significantly increased BBB permeability in a reversible manner by decreasing the expression of claudin 5, an important tight junction protein of brain endothelial cells (BECs) of the BBB, mediated in part by the knockdown of activating transcription factor 4 (ATF4).

CONCLUSIONS

Our findings suggest that engineered sEVs have potential as a strategy for the temporary BBB opening, making it easier for drugs to reach the brain when injected into the bloodstream.

Immunological processes of enhancers and suppressors of long non-coding RNAs associated with brain tumors and inflammation

Immunological processes, such as inflammation, can both cause tumor suppression and cancer progression. Moreover, deregulated levels of long non-coding RNA (lncRNA) expression in the brain may cause inflammation and lead to the growth of tumors. Like other biological processes, the immune system's role in cancer is complicated, varies, and can help or hurt the cancer's maintenance. According to research, inflammation and brain cancer are correlated via several signaling pathways. A variety of lncRNAs have recently been revealed to influence cancer by modulating inflammatory pathways. As a result, lncRNAs have the potential to influence carcinogenesis, tumor formation, or tumor suppression via an increase or decrease in inflammation functions. Although the study and targeting of lncRNAs have made great progress in the treatment of cancer, there are definitely limitations and challenges. Using new technologies like nanocarriers and cell-penetrating peptides (CPPs) to target treatments without hurting healthy body tissues has shown to be very effective. In this review article, we have collected significantly related lncRNAs and their inhibitory or stimulating roles in inflammation and brain cancer for the first time. However, there are limitations, such as side effects and damage to normal tissues. With the advancement of new targeting technologies, these lncRNAs may be candidates for the specific targeting therapy of brain cancers by limiting inflammation or stimulating the immune system against them in the future.

Expression of lncRNAs in glioma: A lighthouse for patients with glioma

Glioma is the most common malignant tumour in the central nervous system, accounting for approximately 30 % of the primary tumours of this system. The World Health Organization grades for glioma include: Grade I (pilocytic astrocytoma), Grade II (astrocytoma, oligodastoma, etc.), Grade III (anaplastic astrocytoma, anaplastic oligodastoma, etc.) and Grade IV (glioblastoma). With grade increases, the proliferation, invasion and other malignant biological properties of the glioma are enhanced, and the treatment results are less satisfactory. The overall survival of patients with glioblastoma is less than 15 months. Recent research has focused on the roles of long non-coding RNAs, previously regarded as "transcriptional noise", in diseases, leading to a new understanding of these roles. Therefore, we conducted this review to explore the progress of research regarding the expression and mechanism of long non-coding RNAs in glioma.

The role of microRNAs in brain metastasis

Brain metastasis (BM) is the most common type of brain tumor and frequently foreshadows disease progression and poor overall survival with patients having a median survival of 6 months. 70,000 new cases of BM are diagnosed each year in the United States (US) and the incidence rate for BM is increasing with improved detection. MicroRNAs (miRNAs) are small non-coding RNAs that serve as critical regulators of gene expression and can act as powerful oncogenes and tumor suppressors. MiRNAs have been heavily implicated in cancer and proposed as biomarkers or therapeutic targets or agents. In this review, we summarize an extensive body of scientific work investigating the role of microRNAs in BM. We discuss miRNA dysregulation, functions, targets, and mechanisms of action in BM and present the current standing of miRNAs as biomarkers and potential therapeutics for BM. We conclude with future directions of miRNA basic and clinical research in BM.

The role and clinical relevance of long non-coding RNAs in glioma

Glioma represents a complex and heterogeneous disease, posing significant challenges to both clinicians and researchers. Despite notable advancements in glioma treatment, the overall survival rate for most glioma patients remains dishearteningly low. Hence, there is an urgent necessity to discover novel biomarkers and therapeutic targets specifically tailored for glioma. In recent years, long non-coding RNAs (lncRNAs) have emerged as pivotal regulators of gene expression and have garnered attention for their involvement in the development and progression of various cancers, including glioma. The dysregulation of lncRNAs plays a critical role in glioma pathogenesis and influences clinical outcomes. Consequently, there is growing interest in exploring the potential of lncRNAs as diagnostic and prognostic biomarkers, as well as therapeutic targets. By understanding the functions and dysregulation of lncRNAs in glioma, researchers aim to unlock new avenues for the development of innovative treatment strategies catered to glioma patients. The identification and thorough characterization of lncRNAs hold the promise of novel therapeutic approaches that could potentially improve patient outcomes and enhance the management of glioma, ultimately striving for better prospects and enhanced quality of life for those affected by this challenging disease. The primary objective of this paper is to comprehensively review the current state of knowledge regarding lncRNA biology and their intricate roles in glioma. It also delves into the potential of lncRNAs as valuable diagnostic and prognostic indicators and explores their feasibility as promising targets for therapeutic interventions.

Urinary Long Non-Coding RNA Levels as Biomarkers of Lupus Nephritis

BACKGROUND

Emerging evidence suggests that long non-coding RNA (lncRNA) plays important roles in the regulation of gene expression. We determine the role of using urinary lncRNA as a non-invasive biomarker for lupus nephritis.

METHOD

We studied three cohorts of lupus nephritis patients (31, 78, and 12 patients, respectively) and controls (6, 7, and 24 subjects, respectively). The urinary sediment levels of specific lncRNA targets were studied using real-time quantitative polymerase chain reactions.

RESULTS

The severity of proteinuria inversely correlated with urinary maternally expressed gene 3 (MEG3) (r = -0.423, p = 0.018) and ANRIL levels (r = -0.483, p = 0.008). Urinary MEG3 level also inversely correlated with the SLEDAI score (r = -0.383, p = 0.034). Urinary cancer susceptibility candidate 2 (CASC2) levels were significantly different between histological classes of nephritis (p = 0.026) and patients with pure class V nephritis probably had the highest levels, while urinary metastasis-associated lung carcinoma transcript 1 (MALAT1) level significantly correlated with the histological activity index (r = -0.321, p = 0.004). Urinary taurine-upregulated gene 1 (TUG1) level was significantly lower in pure class V lupus nephritis than primary membranous nephropathy (p = 0.003) and minimal change nephropathy (p = 0.04), and urinary TUG1 level correlated with eGFR in class V lupus nephritis (r = 0.706, p = 0.01).

CONCLUSIONS

We identified certain urinary lncRNA targets that may help the identification of lupus nephritis and predict the histological class of nephritis. Our findings indicate that urinary lncRNA levels may be developed as biomarkers for lupus nephritis.

Deciphering glioma epitranscriptome: focus on RNA modifications

Gliomas are highly malignant tumors accounting for the majority of brain neoplasms. They are characterized by nuclear atypia, high mitotic rate and cellular polymorphism that often contributes to aggressiveness and resistance to standard therapy. They often associate with challenging treatment approaches and poor outcomes. New treatment strategies or regimens to improve the efficacy of glioma treatment require a deeper understanding of glioma occurrence and development as well as elucidation of their molecular biological characteristics. Recent studies have revealed RNA modifications as a key regulatory mechanism involved in tumorigenesis, tumor progression, immune regulation, and response to therapy. The present review discusses research advances on several RNA modifications involved in glioma progression and tumor microenvironment (TME) immunoregulation as well as in the development of adaptive drug resistance, summarizing current progress on major RNA modification targeting strategies.

Insights into the Role of LncRNAs and miRNAs in Glioma Progression and Their Potential as Novel Therapeutic Targets

Accumulating evidence supports that both long non-coding and micro RNAs (lncRNAs and miRNAs) are implicated in glioma tumorigenesis and progression. Poor outcome of gliomas has been linked to late-stage diagnosis and mostly ineffectiveness of conventional treatment due to low knowledge about the early stage of gliomas, which are not possible to observe with conventional diagnostic approaches. The past few years witnessed a revolutionary advance in biotechnology and neuroscience with the understanding of tumor-related molecules, including non-coding RNAs that are involved in the angiogenesis and progression of glioma cells and thus are used as prognostic biomarkers as well as novel therapeutic targets. The emerging research on lncRNAs and miRNAs highlights their crucial role in glioma progression, offering new insights into the disease. These non-coding RNAs hold significant potential as novel therapeutic targets, paving the way for innovative treatment approaches against glioma. This review encompasses a comprehensive discussion about the role of lncRNAs and miRNAs in gene regulation that is responsible for the promotion or the inhibition of glioma progression and collects the existing links between these key cancer-related molecules.

LncRNA IUR downregulates miR-144 to regulate PTEN in nasopharyngeal carcinoma

IUR is a recently identified oncogenic lncRNA in leukaemia, while its roles in nasopharyngeal carcinoma (NPC) are unclear. We aimed to explore the possible involvement of IUR in NPC. IUR and PTEN were downregulated, while miR-144 was upregulated in NPC. In addition, IUR was inversely correlated with miR-144 and positively correlated with PTEN. In NPC cells, overexpression of IUR resulted in a downregulated expression of miR-144 and an upregulated expression of PTEN. Overexpression of miR-144 led to a downregulated expression of PTEN and attenuated the effects of overexpression of IUR. Cell proliferation assay showed that overexpression of IUR and PTEN resulted in decreased NPC cell proliferation rate. Overexpression of miR-144 played an opposite role and attenuated the effects of overexpression of IUR. In conclusion, IUR can downregulate miR-144 to upregulate PTEN in NPC, therefore inhibiting NPC cell proliferation.

HSF1 and Its Role in Huntington's Disease Pathology

PURPOSE OF REVIEW

Heat shock factor 1 (HSF1) is the master transcriptional regulator of the heat shock response (HSR) in mammalian cells and is a critical element in maintaining protein homeostasis. HSF1 functions at the center of many physiological processes like embryogenesis, metabolism, immune response, aging, cancer, and neurodegeneration. However, the mechanisms that allow HSF1 to control these different biological and pathophysiological processes are not fully understood. This review focuses on Huntington's disease (HD), a neurodegenerative disease characterized by severe protein aggregation of the huntingtin (HTT) protein. The aggregation of HTT, in turn, leads to a halt in the function of HSF1. Understanding the pathways that regulate HSF1 in different contexts like HD may hold the key to understanding the pathomechanisms underlying other proteinopathies. We provide the most current information on HSF1 structure, function, and regulation, emphasizing HD, and discussing its potential as a biological target for therapy.

DATA SOURCES

We performed PubMed search to find established and recent reports in HSF1, heat shock proteins (Hsp), HD, Hsp inhibitors, HSF1 activators, and HSF1 in aging, inflammation, cancer, brain development, mitochondria, synaptic plasticity, polyglutamine (polyQ) diseases, and HD.

STUDY SELECTIONS

Research and review articles that described the mechanisms of action of HSF1 were selected based on terms used in PubMed search.

RESULTS

HSF1 plays a crucial role in the progression of HD and other protein-misfolding related neurodegenerative diseases. Different animal models of HD, as well as postmortem brains of patients with HD, reveal a connection between the levels of HSF1 and HSF1 dysfunction to mutant HTT (mHTT)-induced toxicity and protein aggregation, dysregulation of the ubiquitin-proteasome system (UPS), oxidative stress, mitochondrial dysfunction, and disruption of the structural and functional integrity of synaptic connections, which eventually leads to neuronal loss. These features are shared with other neurodegenerative diseases (NDs). Currently, several inhibitors against negative regulators of HSF1, as well as HSF1 activators, are developed and hold promise to prevent neurodegeneration in HD and other NDs.

CONCLUSION

Understanding the role of HSF1 during protein aggregation and neurodegeneration in HD may help to develop therapeutic strategies that could be effective across different NDs.

lncRNA SERPINB9P1 Regulates SIRT6 Mediated Osteogenic Differentiation of BMSCs via miR-545-3p

Evidence has shown that the altered osteogenic differentiation of human bone marrow stromal cells (BMSCs) under pathological conditions, such as osteoporosis, lead to the imbalance of bone tissue generation and destruction. Recent studies have indicated that long noncoding RNAs may play a role in regulating BMSCs osteogenic differentiation. This contributed to our impetus to move forward with the investigation of the function of lncRNA SERPINB9P1 in osteogenic differentiation of BMSCs and the potential mechanisms involved. Osteogenic differentiation of BMSCs was induced by osteogenic medium. Relative expression of lncRNA SERPINB9P1 and miR-545-3p were tested by qRT-PCR. Osteogenic mineralization was examined by Alizarin S Red staining, ALP staining, and ALP activity assay. Expression of osteoblastic markers were detected by Western blot. RNA-binding protein immunoprecipitation and dual-luciferase reporter assays were performed to test the interaction between lncRNA SERPINB9P1 and miR-545-3p. BMSCs osteogenic differentiation resulted in LncRNA SERPINB9P1 overexpression while miR-545-3p inhibition. Functional assays suggest that knockdown of lncRNA SERPINB9P1 or overexpression of miR-545-3p both inhibit BMSC osteogenic differentiation. lncRNA SERPINB9P1 was proven to regulate the osteogenic differentiation of BMSCs by altering SIRT6 expression through its suppressive effects on miR-545-3p. lncRNA SERPINB9P1 promotes osteogenic differentiation of BMSCs through the miR-545-3p/SIRT6 pathway.

Interplay between mammalian heat shock factors 1 and 2 in physiology and pathology

The heat-shock factors (HSFs) belong to an evolutionary conserved family of transcription factors that were discovered already over 30 years ago. The HSFs have been shown to a have a broad repertoire of target genes, and they also have crucial functions during normal development. Importantly, HSFs have been linked to several disease states, such as neurodegenerative disorders and cancer, highlighting their importance in physiology and pathology. However, it is still unclear how HSFs are regulated and how they choose their specific target genes under different conditions. Posttranslational modifications and interplay among the HSF family members have been shown to be key regulatory mechanisms for these transcription factors. In this review, we focus on the mammalian HSF1 and HSF2, including their interplay, and provide an updated overview of the advances in understanding how HSFs are regulated and how they function in multiple processes of development, aging, and disease. We also discuss HSFs as therapeutic targets, especially the recently reported HSF1 inhibitors.

Altered expression levels of miR-144-3p and ATP1B2 are associated with schizophrenia

Objectives: Schizophrenia is a devastating mental disease. Various microRNAs were proven to be associated with schizophrenia. Altered microRNA-144-3p (miR-144-3p) levels were found in various neurological and psychotic disorders. Beta2-subunit of Na(+)/K(+)-ATPase (ATP1B2) regulates neuronal migration and cell growth during brain development through the PI3K/Akt/mTOR pathway. The present study explored the associations of miR-144-3p and ATP1B2 with schizophrenia and their mutual interaction.Methods: A schizophrenic animal model employing repeated MK-801 administration was established and 293 T cells over-expressing miR-144-3p were constructed by lentivirus. The in vitro and in vivo levels of miR-144-3p, ATP1B2, and the PI3K/Akt/mTOR pathway were examined by qRT-PCR and Western Blots. The interaction between miR-144-3p and ATP1B2 was predicted and assessed by using bioinformatic methods and a luciferase reporter gene assay, respectively.Results: MiR-144-3p expression was elevated in the schizophrenic rat hippocampus. ATP1B2 was down-regulated in schizophrenic patients by analysing GEO datasets. Additionally, miR-144-3p can directly bind with ATP1B2. Furthermore, the ATP1B2 expression and PI3K/Akt/mTOR phosphorylation levels were down-regulated in the 293 T cells over-expressing miR-144-3p and schizophrenic rat hippocampus, which could be reversed by risperidone.Conclusions: This study revealed that up-regulated miR-144-3p might be associated with schizophrenia through down-regulating ATP1B2, implicating new targets of schizophrenia treatment.

Long Non Coding RNA Based Regulation of Cerebrovascular Endothelium

The rapid and high throughput discovery of long non coding RNAs (lncRNAs) has far outstripped the functional annotation of these novel transcripts in their respective cellular contexts. The cells of the blood brain barrier (BBB), especially the cerebrovascular endothelial cells (CVECs), are strictly regulated to maintain a controlled state of homeostasis for undisrupted brain function. Several key pathways are understood in CVEC function that lead to the development and maintenance of their barrier properties, the dysregulation of which leads to BBB breakdown and neuronal injury. Endothelial lncRNAs have been discovered and functionally validated in the past decade, spanning a wide variety of regulatory mechanisms in health and disease. We summarize here the lncRNA-mediated regulation of established pathways that maintain or disrupt the barrier property of CVECs, including in conditions such as ischemic stroke and glioma. These lncRNAs namely regulate the tight junction assembly/disassembly, angiogenesis, autophagy, apoptosis, and so on. The identification of these lncRNAs suggests a less understood mechanistic layer, calling for further studies in appropriate models of the blood brain barrier to shed light on the lncRNA-mediated regulation of CVEC function. Finally, we gather various approaches for validating lncRNAs in BBB function in human organoids and animal models and discuss the therapeutic potential of CVEC lncRNAs along with the current limitations.

Non-coding RNAs in the regulation of blood–brain barrier functions in central nervous system disorders

The blood–brain barrier (BBB) is an essential component of the neurovascular unit that controls the exchanges of various biological substances between the blood and the brain. BBB damage is a common feature of different central nervous systems (CNS) disorders and plays a vital role in the pathogenesis of the diseases. Non-coding RNAs (ncRNAs), such as microRNAs (miRNAs), long non-coding RNA (lncRNAs), and circular RNAs (circRNAs), are important regulatory RNA molecules that are involved in almost all cellular processes in normal development and various diseases, including CNS diseases. Cumulative evidences have demonstrated ncRNA regulation of BBB functions in different CNS diseases. In this review, we have summarized the miRNAs, lncRNAs, and circRNAs that can be served as diagnostic and prognostic biomarkers for BBB injuries, and demonstrated the involvement and underlying mechanisms of ncRNAs in modulating BBB structure and function in various CNS diseases, including ischemic stroke, hemorrhagic stroke, traumatic brain injury (TBI), spinal cord injury (SCI), multiple sclerosis (MS), Alzheimer's disease (AD), vascular cognitive impairment and dementia (VCID), brain tumors, brain infections, diabetes, sepsis-associated encephalopathy (SAE), and others. We have also discussed the pharmaceutical drugs that can regulate BBB functions via ncRNAs-related signaling cascades in CNS disorders, along with the challenges, perspective, and therapeutic potential of ncRNA regulation of BBB functions in CNS diseases.

LncRNA Tug1 maintains blood-testis barrier integrity by modulating Ccl2 expression in high-fat diet mice

Sertoli cells are essential for spermatogenesis in the testicular seminiferous tubules by forming blood-testis barrier (BTB) and creating a unique microenvironment for spermatogenesis. Many lncRNAs have been reported to participate in spermatogenesis. However, the role of long noncoding RNAs (lncRNAs) in Sertoli cells has rarely been examined. Herein, we found that a high-fat diet (HFD) decreased sperm quality, impaired BTB integrity and resulted in accumulation of saturated fatty acids (SFAs), especially palmitic acid (PA), in mouse testes. PA decreased the expression of tight junction (TJ)-related proteins, increased permeability and decreased transepithelial electrical resistance (TER) in primary Sertoli cells and TM4 cells. Moreover, lncRNA Tug1 was found to be involved in PA-induced BTB disruption by RNA-seq. Tug1 depletion distinctly impaired the TJs of Sertoli cells and overexpression of Tug1 alleviated the disruption of BTB integrity induced by PA. Moreover, Ccl2 was found to be a downstream target of Tug1, and decreased TJ-related protein levels and TER and increased FITC-dextran permeability in vitro. Furthermore, the addition of Ccl2 damaged BTB integrity after overexpression of Tug1 in the presence of PA. Mechanistically, we found that Tug1 could directly bind to EZH2 and regulate H3K27me3 occupancy in the Ccl2 promoter region by RNA immunoprecipitation and chromatin immunoprecipitation assays. Our study revealed an important role of Tug1 in the BTB integrity of Sertoli cells and provided a new view of the role of lncRNAs in male infertility.

The Long-Noncoding RNA TUG1 Regulates Oxygen-Induced Retinal Neovascularization in Mice via MiR-299

Purpose

The oxygen-induced retinal neovascularization mouse model closely approximates pathological changes associated with human retinal neovascularization-associated diseases, including retinopathies. We used this model and human retinal endothelial cells (HRECs) under hypoxia to explore the relationship between taurine upregulated gene-1 (TUG1), vascular endothelial growth factor (VEGF), and miR-299-3p on retinopathy of prematurity (ROP).

Methods

An oxygen-induced retinopathy (OIR) mouse model was established; the mice were divided into a normal control group, OIR group, TUG1 control group (lentivirus control), and TUG1-knockdown group. The apoptosis of retinal cells was evaluated using a TUNEL assay. Angiogenic, apoptotic, and inflammatory factors were detected by Western blot, immunohistochemistry, and immunofluorescence analyses. HRECs were cultured under hypoxia and assessed for VEGF expression, apoptosis, tubule formation, and migration ability. The relationship between TUG1, VEGF, and miR-299-3p was detected via a dual luciferase reporter gene assay.

Results

Intravitreal injection of TUG1 lentivirus reduced the inflammatory response in the mouse retinal tissue and markedly reduced pathological changes in the retina. Overexpression of miR-299 in HRECs reduced the apoptosis rate, tube formation, and migration ability of hypoxia-treated cells, thereby inhibiting the formation of new blood vessels. The dual luciferase reporter gene assay suggested that miR-299 has binding sites for TUG1 and VEGF.

Conclusions

TUG1 reduces the expression of VEGFA by competitively adsorbing miR-299-3p and facilitates the regulation of retinal neovascularization, suggesting that it may serve as a new therapeutic target for retinal neovascular diseases.

Role of mammalian long non-coding RNAs in normal and neuro oncological disorders

Long non-coding RNAs (lncRNAs) are expressed at lower levels than protein-coding genes but have a crucial role in gene regulation. LncRNA is distinct, they are being transcribed using RNA polymerase II, and their functionality depends on subcellular localization. Depending on their niche, they specifically interact with DNA, RNA, and proteins and modify chromatin function, regulate transcription at various stages, forms nuclear condensation bodies and nucleolar organization. lncRNAs may also change the stability and translation of cytoplasmic mRNAs and hamper signaling pathways. Thus, lncRNAs affect the physio-pathological states and lead to the development of various disorders, immune responses, and cancer. To date, ~40% of lncRNAs have been reported in the nervous system (NS) and are involved in the early development/differentiation of the NS to synaptogenesis. LncRNA expression patterns in the most common adult and pediatric tumor suggest them as potential biomarkers and provide a rationale for targeting them pharmaceutically. Here, we discuss the mechanisms of lncRNA synthesis, localization, and functions in transcriptional, post-transcriptional, and other forms of gene regulation, methods of lncRNA identification, and their potential therapeutic applications in neuro oncological disorders as explained by molecular mechanisms in other malignant disorders.

Non-coding RNAs: the extensive and interactive regulators of the blood-brain barrier permeability

The blood-brain barrier (BBB), which controls permeability into and out of the nervous system, is a tightly connected, structural, and functional separation between the central nervous system (CNS) and circulating blood. CNS diseases, such as Alzheimer’s disease, multiple sclerosis, traumatic brain injury, stroke, meningitis, and brain cancers, often develop with the increased BBB permeability and further leads to irreversible CNS injury. Non-coding RNAs (ncRNAs) are functional RNA molecules that generally lack the coding abilities but can actively regulate the mRNA expression and function through different mechanisms. Various types of ncRNAs, including microRNAs (miRNAs), long ncRNAs (lncRNAs), and circular RNAs (circRNAs), are highly expressed in brain microvascular endothelial cells and are potential mediators of BBB permeability. Here, we summarized the recent research progress on miRNA, lncRNA, and circRNA roles regulating the BBB permeability in different CNS diseases. Understanding how these ncRNAs affect the BBB permeability shall provide important therapeutic insights into the prevention and control of the BBB dysfunction.

Long Non-Coding RNAs in Diagnosis, Treatment, Prognosis, and Progression of Glioma: A State-of-the-Art Review

Glioma is the most common malignant central nervous system tumor with significant mortality and morbidity. Despite considerable advances, the exact molecular pathways involved in tumor progression are not fully elucidated, and patients commonly face a poor prognosis. Long non-coding RNAs (lncRNAs) have recently drawn extra attention for their potential roles in different types of cancer as well as non-malignant diseases. More than 200 lncRNAs have been reported to be associated with glioma. We aimed to assess the roles of the most investigated lncRNAs in different stages of tumor progression and the mediating molecular pathways in addition to their clinical applications. lncRNAs are involved in different stages of tumor formation, invasion, and progression, including regulating the cell cycle, apoptosis, autophagy, epithelial-to-mesenchymal transition, tumor stemness, angiogenesis, the integrity of the blood-tumor-brain barrier, tumor metabolism, and immunological responses. The well-known oncogenic lncRNAs, which are upregulated in glioma, are H19, HOTAIR, PVT1, UCA1, XIST, CRNDE, FOXD2-AS1, ANRIL, HOXA11-AS, TP73-AS1, and DANCR. On the other hand, MEG3, GAS5, CCASC2, and TUSC7 are tumor suppressor lncRNAs, which are downregulated. While most studies reported oncogenic effects for MALAT1, TUG1, and NEAT1, there are some controversies regarding these lncRNAs. Expression levels of lncRNAs can be associated with tumor grade, survival, treatment response (chemotherapy drugs or radiotherapy), and overall prognosis. Moreover, circulatory levels of lncRNAs, such as MALAT1, H19, HOTAIR, NEAT1, TUG1, GAS5, LINK-A, and TUSC7, can provide non-invasive diagnostic and prognostic tools. Modulation of expression of lncRNAs using antisense oligonucleotides can lead to novel therapeutics. Notably, a profound understanding of the underlying molecular pathways involved in the function of lncRNAs is required to develop novel therapeutic targets. More investigations with large sample sizes and increased focus on in-vivo models are required to expand our understanding of the potential roles and application of lncRNAs in glioma.

Involvement of noncoding RNA in blood-brain barrier integrity in central nervous system disease

Given the important role of the blood-brain barrier (BBB) in the central nervous system (CNS), increasing studies have been carried out to determine how the structural and functional integrity of the BBB impacts the pathogenesis of CNS diseases such as stroke, traumatic brain injuries (TBIs), and gliomas. Emerging studies have revealed that noncoding RNAs (ncRNAs) help to maintain the integrity and permeability of the BBB, thereby mediating CNS homeostasis. This review summarizes recent studies that focus on the effects of ncRNAs on the BBB in CNS diseases, including regulating the biological processes of inflammation, necrosis, and apoptosis of cells, affecting the translational dysfunction of proteins and regulating tight junctions (TJs). A comprehensive and detailed understanding of the interaction between ncRNAs and the BBB will lay a solid foundation for the development of early diagnostic methods and effective treatments for CNS diseases.

Knockdown of Long Non-Coding RNA HCP5 Increases Radiosensitivity Through Cellular Senescence by Regulating microRNA-128 in Gliomas

Introduction

Glioma is the most common malignant brain tumor in adults. Radiation is a key therapy in glioma. However, the radioresistance of glioma was a big challenge. HLA complex P5 (HCP5) has been reported dysregulated in several types of malignant tumor, including glioma. The role of HCP5 in the radiosensitivity of glioma is so far unknown. The present study aimed to investigate the effect of HCP5 on radiosensitivity in gliomas.

Methods

The levels of HCP5 and microRNA (miR)-128 were detected using qRT-PCR. The cell growth curve was used to show the cell proliferation and evaluate the radiosensitivity of glioma cells following exposure to X-ray. Senescence-associated β-galactosidase (SA-β-Gal) staining was used to test the cellular senescence. Luciferase reporter and RNA immunoprecipitation (RIP) assays were performed to determine the correlation between HCP5 and miR-128.

Results

HCP5 level of glioma cells was significantly higher than human astrocytes, whereas miR-128 level was lower in glioma cells. Besides, the HCP5 expression was increased in glioma tissues compared to normal brain tissues (NBTs). Knockdown of HCP5 inhibited cell proliferation and increased radiosensitivity in glioma cells. MiR-128 was predicted to be a target of HCP5. It was demonstrated that HCP5 directly bound to miR-128 and regulated its expression in glioma cells. Furthermore, the effects of HCP5 knockdown on radiosensitivity of glioma cells were attenuated by the inhibitor of miR-128.

Conclusion

These findings suggested that interaction between lncRNA HCP5 and microRNA-128 could regulate the radiosensitivity of glioma cells by intervening in cellular senescence. This might be used as the potential radio-sensitization targets for glioma therapy.

LncRNAs associated with glioblastoma: From transcriptional noise to novel regulators with a promising role in therapeutics

Glioblastoma multiforme (GBM) is the most widespread and aggressive subtype of glioma in adult patients. Numerous long non-coding RNAs (lncRNAs) are deregulated or differentially expressed in GBM. These lncRNAs possess unique regulatory functions in GBM cells, ranging from high invasion/migration to recurrence. This review outlines the present status of specific involvement of lncRNAs in GBM pathogenesis, with a focus on their association with key molecular and cellular regulatory mechanisms. Also, we highlighted the potential of different novel RNA-based strategies that may be beneficial for therapeutic purposes.

Potential of long non-coding RNAs as a therapeutic target and molecular markers in glioblastoma pathogenesis

Glioblastoma (GB) is by far the most hostile type of malignant tumor that primarily affects the brain and spine, derived from star-shaped glial cells that are astrocytes and oligodendrocytes. Despite of significant efforts in recent years in glioblastoma research, the clinical efficacy of existing medical intervention is still limited and very few potential diagnostic markers are available. Long non-coding RNAs (lncRNAs) that lacks protein-coding capabilities were previously thought to be "junk sequences" in mammalian genomes are quite indispensible epigenetic regulators that can positively or negatively regulate gene expression and nuclear architecture, with significant roles in the initiation and development of tumors. Nevertheless, the precise mechanism of these distortedly expressed lncRNAs in glioblastoma pathogenesis is not yet fully understood. Since the advent of high-throughput sequencing technologies, more and more research have elucidated that lncRNAs are one of the most promising prognostic biomarkers and therapeutic targets for glioblastoma. In this paper, I briefly outlined the existing findings of lncRNAs. And also summarizes the profiles of different lncRNAs that have been broadly classified in glioblastoma research, with emphasis on both their prognostic and therapeutic values.

Long Non-coding RNA MALAT1 Upregulates ZEB2 Expression to Promote Malignant Progression of Glioma by Attenuating miR-124

Long non-coding RNA (lncRNA) metastasis-associated lung adenocarcinoma transcript 1 (MALAT1) has been shown to play a critical role in the development of several malignancies. However, the potential molecular mechanism of MALAT1 in glioma remains unclear. In the present study, we found that the expression of MALAT1 was aberrantly increased in both human glioma tissues and cells and associated with poor prognosis in glioma patients. We further found that MALAT1 silencing significantly inhibited glioma cell proliferation while induced cell cycle arrest and apoptosis. In parallel, knockdown of MALAT1 decreased tumor volume in vivo. These results suggested that MALAT1 acts as a functional oncogene, resulting in the oncogenicity in glioma. Nevertheless, the tumor-suppressive effect of MALAT1 silencing was reversed by miR-124. Besides, the relevance of ZEB2 in tumor progression has been studied in several forms of human cancer, and ZEB2 was identified as a target of miR-124 and negatively regulated by miR-124. MALAT1 overexpression or miR-124 inhibitor led to increased expression of ZEB2. In summary, our study depicts a novel pathway of MALAT1/miR-124/ZEB2 that regulates the progression of glioma and might provide a promising strategy for glioma therapy.

Long non-coding RNAs in brain tumors

Long non-coding RNAs (lncRNAs) have been found to be central players in the epigenetic, transcriptional and post-transcriptional regulation of gene expression. There is an accumulation of evidence on newly discovered lncRNAs, their molecular interactions and their roles in the development and progression of human brain tumors. LncRNAs can have either tumor suppressive or oncogenic functions in different brain cancers, making them attractive therapeutic targets and biomarkers for personalized therapy and precision diagnostics. Here, we summarize the current state of knowledge of the lncRNAs that have been implicated in brain cancer pathogenesis, particularly in gliomas and medulloblastomas. We discuss their epigenetic regulation as well as the prospects of using lncRNAs as diagnostic biomarkers and therapeutic targets in patients with brain tumors.

Urinary expression of long non-coding RNA TUG1 in non-diabetic patients with glomerulonephritides

Metabolic alterations serve a significant role in the pathogenesis of kidney disease. Long non-coding RNA (lncRNA) taurine upregulated gene 1 (TUG1) is a known regulator of podocyte health and mitochondrial biogenesis. Although TUG1 protects against podocyte loss in models of diabetic nephropathy, it is unknown if urinary TUG1 expression is associated with clinical and histopathological findings in non-diabetic patients diagnosed with glomerulonephritides. In the present study, the expression of TUG1, podocyte-specific markers (nephrin and podocin) and mitochondrial biogenesis-associated mRNAs (transcription factor A mitochondrial, cytochrome C oxidase subunit 5A and peroxisome proliferator-activated receptor γ coactivator 1α) were examined in urinary sediment of non-diabetic patients with biopsy-confirmed glomerulonephritides and healthy controls. Urinary expression of TUG1 was significantly lower in patients with glomerulonephritides, particularly those diagnosed with Focal Segmental Glomerulosclerosis (FSGS). Furthermore, TUG1 levels were associated with urinary expression of podocyte-specific markers and mRNAs associated with mitochondrial biogenesis. Loss of TUG1 expression in urinary sediment was strongly associated with FSGS, highlighting the potential of this lncRNA and its mitochondrial biogenesis-associated targets as non-invasive biomarkers of assessing podocytopathy.

Pathophysiological Functions of the lncRNA TUG1

BACKGROUND

Long non-coding RNAs (lncRNAs) with little or no coding capacity are associated with a plethora of cellular functions, participating in various biological processes. Cumulative study of lncRNA provides explanations to the physiological and pathological processes and new perspectives to the diagnosis, prevention, and treatment of some clinical diseases. Long non-coding RNA taurine-upregulated gene 1(TUG1) is one of the first identified lncRNAs associated with human disease, which actively involved in various physiological processes, including regulating genes at epigenetics, transcription, post-transcription, translation, and posttranslation. The aim of this review was to explore the molecular mechanism of TUG1 in various types of human diseases.

METHODS

In this review, we summarized and analyzed the latest findings related to the physiologic and pathophysiological processes of TUG1 in human diseases. The related studies were retrieved and selected the last six years of research articles in PubMed with lncRNA and TUG1 as keywords.

RESULTS

TUG1 is a valuable lncRNA that its dysregulated expression and regulating the biological processes were found in a variety of human diseases. TUG1 is found to exhibit aberrant expression in a variety of malignancies. Dysregulation of TUG1 has been shown to contribute to proliferation, migration, cell cycle changes, inhibited apoptosis, and drug resistance of cancer cells, which revealed an oncogenic role for this lncRNA, but some reports have shown downregulation of TUG1 in lung cancer samples compared with noncancerous samples. In addition, the molecular and biological functions of TUG1 in physiology and disease (relevant to endocrinology, metabolism, immunology, neurobiology) have also been highlighted. Finally, we discuss the limitations and tremendous diagnostic/therapeutic potential of TUG1 in cancer and other diseases.

CONCLUSION

Long non-coding RNA-TUG1 likely served as useful disease biomarkers or therapy targets and effectively applied in different kinds of diseases, such as human cancer and cardiovascular diseases.

Brain Tumor-Derived Extracellular Vesicles as Carriers of Disease Markers: Molecular Chaperones and MicroRNAs

Primary and metastatic brain tumors are usually serious conditions with poor prognosis, which reveal the urgent need of developing rapid diagnostic tools and efficacious treatments. To achieve these objectives, progress must be made in the understanding of brain tumor biology, for example, how they resist natural defenses and therapeutic intervention. One resistance mechanism involves extracellular vesicles that are released by tumors to meet target cells nearby or distant via circulation and reprogram them by introducing their cargo. This consists of different molecules among which are microRNAs (miRNAs) and molecular chaperones, the focus of this article. miRNAs modify target cells in the immune system to avoid antitumor reaction and chaperones are key survival molecules for the tumor cell. Extracellular vesicles cargo reflects the composition and metabolism of the original tumor cell; therefore, it is a source of markers, including the miRNAs and chaperones discussed in this article, with potential diagnostic and prognostic value. This and their relatively easy availability by minimally invasive procedures (e.g., drawing venous blood) illustrate the potential of extracellular vesicles as useful materials to manage brain tumor patients. Furthermore, understanding extracellular vesicles circulation and interaction with target cells will provide the basis for using this vesicle for delivering therapeutic compounds to selected tumor cells.

Non-Coding RNAs in Multiple Myeloma Bone Disease Pathophysiology

Bone remodeling is uncoupled in the multiple myeloma (MM) bone marrow niche, resulting in enhanced osteoclastogenesis responsible of MM-related bone disease (MMBD). Several studies have disclosed the mechanisms underlying increased osteoclast formation and activity triggered by the various cellular components of the MM bone marrow microenvironment, leading to the identification of novel targets for therapeutic intervention. In this regard, recent attention has been given to non-coding RNA (ncRNA) molecules, that finely tune gene expression programs involved in bone homeostasis both in physiological and pathological settings. In this review, we will analyze major signaling pathways involved in MMBD pathophysiology, and report emerging evidence of their regulation by different classes of ncRNAs.

Role of taurine, its haloamines and its lncRNA TUG1 in both inflammation and cancer progression. On the road to therapeutics? (Review)

For one century, taurine is considered as an end product of sulfur metabolism. In this review, we discuss the beneficial effect of taurine, its haloamines and taurine upregulated gene 1 (TUG1) long non‑coding RNA (lncRNA) in both cancer and inflammation. We outline how taurine or its haloamines (N‑Bromotaurine or N‑Chlorotaurine) can induce robust and efficient responses against inflammatory diseases, providing insight into their molecular mechanisms. We also provide information about the use of taurine as a therapeutic approach to cancer. Taurine can be combined with other chemotherapeutic drugs, not only mediating durable responses in various malignancies, but also circumventing the limitations met from chemotherapeutic drugs, thus improving the therapeutic outcome. Interestingly, the lncRNA TUG1 is regarded as a promising therapeutic approach, which can overcome acquired resistance of cancer cells to selected strategies. In this regard, we can translate basic knowledge about taurine and its TUG1 lncRNA into potential therapeutic options directed against specific oncogenic signaling targets, thereby bridging the gap between bench and bedside.

Inhibition of lncRNA LINC00461/miR-216a/aquaporin 4 pathway suppresses cell proliferation, migration, invasion, and chemoresistance in glioma

Long noncoding RNA (lncRNA) LINC00461 (LINC00461) is reported to be related to glioma progression. However, the mechanism of LINC00461 in glioma remains unclear. Expression of LINC00461, miRNA (miR)-216a, and aquaporin 4 (AQP4) was detected using real-time quantitative PCR (RT-qPCR) and western blotting. Proliferation, temozolomide (TMZ) resistance, migration, and invasion were assessed by MTT, colony formation, and transwell assays, respectively. The target binding among miR-216a, LINC00461, and AQP4 was confirmed by the luciferase reporter assay. The tumor growth was monitored in the xenograft experiment. LINC00461 was upregulated, and miR-216a was downregulated in glioma tissues and cells, and LINC00461 upregulation was correlated with large tumor size, higher WHO grade and recurrence, and poor overall survival. LINC00461 knockdown suppressed cell viability, abilities of cell cloning and migration and invasion, and TMZ resistance in glioma. Mechanically, LINC00461 was confirmed to sponge miR-216a to affect AQP4 expression. Rescue assays verified that miR-216a downregulation or AQP4 upregulation abrogated the inhibitory effect of LINC00461 knockdown on cell proliferation, migration, invasion, and TMZ resistance in vitro. Moreover, LINC00461 downregulation blocked the glioma tumor growth in vivo. In conclusion, LINC00461 knockdown inhibits glioma cell proliferation, migration, invasion, and TMZ resistance through miR-216a/AQP4 axis, suggesting LINC00461 as an oncogene in glioma progression.

Long-chain non-coding RNA HOTAIR promotes the progression of osteoarthritis via sponging miR-20b/PTEN axis

AIMS

Cumulative evidence suggests that long-chain non-coding RNA (lncRNA) is involved in the pathogenesis of osteoarthritis (OA). The present study aimed to explore the regulatory role and related mechanisms of HOX transcript antisense intergenic RNA (HOTAIR) in OA.

MATERIAL AND METHODS

The OA mouse model was constructed by the medial meniscus (DMM) method, and Interleukin (IL)-1β-induced chondrocytes were used to simulate OA in vitro.

KEY FINDINGS

Results found that HOTAIR was significantly up-regulated in articular cartilage tissues of OA mice and IL-1β-induced chondrocytes, accompanied by down-regulation of miR-20b and increased expression of the phosphatase and tensin homolog (PTEN). HOTAIR silencing improved cartilage tissue damage in OA mice, and promoted the expression of collagen II and aggrecan in cartilage tissue, while inhibited the expression of matrix metalloproteinases (MMP)-13 and ADAMTS-5. Overexpression of HOTAIR inhibited the proliferation of IL-1β-induced chondrocytes and promoted apoptosis and extracellular matrix (ECM) degradation, whereas the effect of HOTAIR knockdown was reversed. Bioinformatics software and luciferase reporter experiments confirmed that HOTAIR could negatively regulate miR-20b, and PTEN was a target gene of miR-20b. An increase in PTEN expression induced by HOTAIR overexpression could be reversed by the introduction of miR-20b mimic. HOTAIR overexpression significantly reversed miR-20 mimic-mediated inhibition of apoptosis and ECM degradation in IL-1β-induced chondrocytes, whereas the introduction of si-HOTAIR eliminated anti-miR-20b-mediated apoptosis and ECM degradation.

SIGNIFICANCE

HOTAIR can participate in OA by promoting chondrocyte apoptosis and ECM degradation, which may be related to its targeted regulation of miR-20b/PTEN axis.

Coding of Glioblastoma Progression and Therapy Resistance through Long Noncoding RNAs

Glioblastoma is the most aggressive and lethal primary brain malignancy, with an average patient survival from diagnosis of 14 months. Glioblastoma also usually progresses as a more invasive phenotype after initial treatment. A major step forward in our understanding of the nature of glioblastoma was achieved with large-scale expression analysis. However, due to genomic complexity and heterogeneity, transcriptomics alone is not enough to define the glioblastoma "fingerprint", so epigenetic mechanisms are being examined, including the noncoding genome. On the basis of their tissue specificity, long noncoding RNAs (lncRNAs) are being explored as new diagnostic and therapeutic targets. In addition, growing evidence indicates that lncRNAs have various roles in resistance to glioblastoma therapies (e.g., MALAT1, H19) and in glioblastoma progression (e.g., CRNDE, HOTAIRM1, ASLNC22381, ASLNC20819). Investigations have also focused on the prognostic value of lncRNAs, as well as the definition of the molecular signatures of glioma, to provide more precise tumor classification. This review discusses the potential that lncRNAs hold for the development of novel diagnostic and, hopefully, therapeutic targets that can contribute to prolonged survival and improved quality of life for patients with glioblastoma.

Downregulation of LncRNA TUG1 Inhibited TLR4 Signaling Pathway-Mediated Inflammatory Damage After Spinal Cord Ischemia Reperfusion in Rats via Suppressing TRIL Expression

Toll-like receptor 4 (TLR4) and TLR4 interactor with leucine-rich repeats (TRIL) play a crucial role in the inflammatory response. This study investigated the role of long noncoding RNA taurine-upregulated gene 1 (lncRNA TUG1) in TRIL/TLR4 signaling in spinal cord ischemia reperfusion (IR) injury. IR injury was induced in experimental rats; knockdown of TUG1 and TRIL was induced by intrathecal injection of siRNAs and overexpression of TRIL was induced by pcDNA3.3-TRIL. The results showed that the mRNA levels of TUG1 were increased at 12 hours after IR; this was accompanied by increased expression of the TRIL- and TLR4-mediated NF-κB/IL-1β signaling pathway. Activated microglia, detected with increased ionized calcium-binding adapter molecule 1 as a marker, exacerbated the hind-limb neurological impairment and blood-spinal cord barrier (BSCB) leakage after IR. TUG1 knockdown inhibited expression of TRIL and TLR4 signaling proinflammatory cytokines and microglial activation, and attenuated neurological deficit and BSCB leakage. TRIL knockdown inhibited the TLR4-mediated inflammatory response, while TRIL expression reversed the inhibited inflammatory effect caused by TUG1 knockdown. These data suggest that TUG1 knockdown inhibited inflammatory damage of the TLR4-mediated NF-κB/IL-1β signaling pathway after IR via suppressing TRIL expression.

MiR-144: A New Possible Therapeutic Target and Diagnostic/Prognostic Tool in Cancers

MicroRNAs (miRNAs) are small and non-coding RNAs that display aberrant expression in the tissue and plasma of cancer patients when tested in comparison to healthy individuals. In past decades, research data proposed that miRNAs could be diagnostic and prognostic biomarkers in cancer patients. It has been confirmed that miRNAs can act either as oncogenes by silencing tumor inhibitors or as tumor suppressors by targeting oncoproteins. MiR-144s are located in the chromosomal region 17q11.2, which is subject to significant damage in many types of cancers. In this review, we assess the involvement of miR-144s in several cancer types by illustrating the possible target genes that are related to each cancer, and we also briefly describe the clinical applications of miR-144s as a diagnostic and prognostic tool in cancers.

Mast cells-derived MiR-223 destroys intestinal barrier function by inhibition of CLDN8 expression in intestinal epithelial cells

Background

Mast cells (MCs) have been found to play a critical role during development of inflammatory bowel disease (IBD) that characterized by dysregulation of inflammation and impaired intestinal barrier function. However, the function of MCs in IBD remains to be fully elucidated.

Results

In our study, we used exosomes isolated from human mast cells-1 (HMCs-1) to culture with NCM460, HT-29 or CaCO2 of intestinal epithelial cells (IECs) to investigate the communication between MCs and IECs. We found that MCs-derived exosomes significantly increased intestinal epithelial permeability and destroyed intestinal barrier function, which is attributed to exosome-mediated functional miRNAs were transferred from HMCs-1 into IECs, leading to inhibit tight junction-related proteins expression, including tight junction proteins 1 (TJP1, ZO-1), Occludin (OCLN), Claudin 8 (CLDN8). Microarray and bioinformatic analysis have further revealed that a panel of miRNAs target different tight junction-related proteins. Interestingly, miR-223 is enriched in mast cell-derived exosome, which inhibit CLDN8 expression in IECs, while treatment with miR-223 inhibitor in HT-29 cells significantly reversed the inhibitory effect of HMCs-1-derived exosomes on CLDN 8 expression. Most importantly, enrichment of MCs accumulation in intestinal mucosa of patients with IBD compared with those healthy control.

Conclusions

These results indicated that enrichment of exosomal miR-223 from HMCs-1 inhibited CLDN8 expression, leading to destroy intestinal barrier function. These finding provided a novel insight of MCs as a new target for therapeutic treatment of IBD.

Suspended in time: Molecular responses to hibernation also promote longevity

Aging in most animals is an inevitable process that causes or is a result of physiological, biochemical, and molecular changes in the body, and has a strong influence on an organism's lifespan. Although advancement in medicine has allowed humans to live longer, the prevalence of age-associated medical complications is continuously burdening older adults worldwide. Current animal models used in research to study aging have provided novel information that has helped investigators understand the aging process; however, these models are limiting. Aging is a complex process that is regulated at multiple biological levels, and while a single manipulation in these models can provide information on a process, it is not enough to understand the global regulation of aging. Some mammalian hibernators live up to 9.8-times higher than their expected average lifespan, and new research attributes this increase to their ability to hibernate. A common theme amongst these mammalian hibernators is their ability to greatly reduce their metabolic rate to a fraction of their normal rate and initiate cytoprotective responses that enable their survival. Metabolic rate depression is strictly regulated at different biological levels in order to enable the animal to not only survive, but to also do so by relying mainly on their limited internal fuels. As such, understanding both the global and specific regulatory mechanisms used to promote survival during hibernation could, in theory, allow investigators to have a better understanding of the aging process. This can also allow pharmaceutical industries to find therapeutics that could delay or reverse age-associated medical complications and promote healthy aging and longevity in humans.

LncRNA FTX Promotes Proliferation and Invasion of Gastric Cancer via miR-144/ZFX Axis

BACKGROUND

Long non-coding RNAs are important regulators in cancer cell tumorigenesis. We have demonstrated in a prior study that lncRNA FTX is dysregulated in gastric cancer (GC). In this study, we aim to report gastric cancer-related lncRNA FTX as a main regulator in GC development and progression.

METHODS

In vitro and in vivo assays of FTX alterations have been performed to reveal a complex integrated phenotype affecting cell growth, migration, and invasion. lncRNA FTX expression levels in gastric cancer cells and normal cells were measured by RT-PCR. Luciferase reporter assays, Western blotting, and many immune, microscopy technologies were utilized to investigate the expressions of FTX- related proteins and RNAs. The functional role of FTX in cell growth, migration, and invasion were observed in vitro and in vivo.

RESULTS

We explored the underlying mechanisms of FTX in GC development, and the microRNAs' relationship with FTX. We found that FTX promoted cell proliferation, migration, and invasion, as well as tumor growth, and this effect could latterly be attenuated by miR-144. ZFX attenuated the effects of FTX/miR-144 axis by sponging with miR-144.

CONCLUSION

In summary, the above results support a model in which the FTX/miR-144/ZFX act as important effectors in GC tumorigenesis and progression, indicating new therapeutic methods in GC.

MicroRNAs in central nervous system diseases: A prospective role in regulating blood-brain barrier integrity

Given the essential role of the blood-brain barrier (BBB) in the central nervous system (CNS), cumulative investigations have been performed to elucidate how modulation of BBB structural and functional integrity affects the pathogenesis of CNS diseases such as stroke, traumatic brain injuries, dementia, and cerebral infection. Recent studies have demonstrated that microRNAs (miRNAs) contribute to the maintenance of the BBB and thereby mediate CNS homeostasis. This review summarizes emerging studies that demonstrate cerebral miRNAs regulate BBB function in CNS disorders, emphasizing the direct role of miRNAs in BBB molecular composition. Evidence presented in this review will encourage a deeper understanding of the mechanisms by which miRNAs regulate BBB function, and facilitate the development of new miRNAs-based therapies in patients with CNS diseases.

Noncoding RNA Regulation of Dormant States in Evolutionarily Diverse Animals

Dormancy is evolutionarily widespread and can take many forms, including diapause, dauer formation, estivation, and hibernation. Each type of dormancy is characterized by distinct features; but accumulating evidence suggests that each is regulated by some common processes, often referred to as a common "toolkit" of regulatory mechanisms, that likely include noncoding RNAs that regulate gene expression. Noncoding RNAs, especially microRNAs, are well-known regulators of biological processes associated with numerous dormancy-related processes, including cell cycle progression, cell growth and proliferation, developmental timing, metabolism, and environmental stress tolerance. This review provides a summary of our current understanding of noncoding RNAs and their involvement in regulating dormancy.

Molecular mechanisms of TUG1 in the proliferation, apoptosis, migration and invasion of cancer cells

Long non-coding RNAs (lncRNAs) are RNA sequences >200 nucleotides in length that have no protein-coding capacity. lncRNAs serve key roles in multiple biological processes, such as tumorigenesis and tumor progression. Taurine upregulated 1 (TUG1) is a novel lncRNA that has been associated with human cancer. TUG1 has attracted increasing attention in recent years and has been documented to be abnormally expressed in different types of cancer. Numerous studies indicate that TUG1 may be significantly associated with tumor development and cell metabolism by regulating cell proliferation, invasion, metastasis, apoptosis, differentiation and drug resistance. TUG1 exerts its function via recruiting specific RNA-binding proteins, promoting target gene expression, influencing tumor angiogenesis and by functioning as a competing endogenous RNA (ceRNA). An increasing number of studies have demonstrated that ceRNAs serve a role in cancer development. TUG1 is considered to be a biomarker or a novel therapeutic target for the diagnosis and prognosis of different cancer types. The present review focuses on recent developments in the major underlying molecular mechanisms of TUG1 in cancer, including its role in cell proliferation, apoptosis, migration, invasion and drug resistance. Also discussed in the present review is the current knowledge regarding the regulation of TUG1.

Downregulation of long non-coding RNA TUG1 suppresses tumor growth by promoting ubiquitination of MET in diffuse large B-cell lymphoma

Long non-coding RNAs (lncRNAs) can modulate gene expression through different mechanisms, but the fundamental molecular mechanism between lncRNAs and MET protein in diffuse large B-cell lymphoma (DLBCL) was poorly understood. The expression of lncRNA TUG1 and MET in DLBCL tissues and cell lines was determined by quantitative real-time PCR and western blotting. Cell proliferation, invasion and apoptosis were determined by cell counting kit-8 assay, transwell assay and flow cytometer. The animal xenograft model was established by the injection of DLBCL cells carrying si-TUG1. The expression of TUG1 and MET was upregulated in DLBCL tissues and cells. We demonstrated that MET was altered in the TUG1 knockdown DLBCL cells, and confirmed the interaction between TUG1 and MET by RNA pull-down and RNA immunoprecipitation. Furthermore, knockdown of TUG1 reduced MET protein level by promoting ubiquitination, and suppressed tumor growth in vitro and in vivo. Our findings demonstrated that TUG1 exerted its oncogenic function in DLBCL by inhibiting the ubiquitination and the subsequent degradation of MET. Knockdown of TUG1 through MET downregulation suppressed DLBCL cell proliferation and tumor growth.

LncRNA TUG1 contributes to cardiac hypertrophy via regulating miR-29b-3p

Cardiac hypertrophy with maladjusted cardiac remodeling is the leading cause of heart failure. In the past decades, long non-coding RNAs (lncRNAs) and microRNAs (miRNAs) have been proved to exert multiple functions in cellular biological behaviors; however, their role in cardiac hypertrophy remains largely unclear. Presently, we first obtained hypertrophic H9c2 cells by treating with angiotensin II (Ang II) and uncovered upregulation of lncRNA taurine upregulated gene 1 (TUG1) in such H9c2 cells. Then, we demonstrated that silencing TUG1 attenuated Ang II-induced cardiac hypertrophy. Besides, a strong interactivity of TUG1 with miR-29b-3p at the putative sites was validated, suggesting that TUG1 was an endogenous sponge of miR-29b-3p in H9c2 cells. Additionally, the expression of miR-29b-3p was strikingly reduced by TUG1 upregulation and also inhibited under Ang II treatment, whereas it was restored after silencing TUG1 in hypertrophic cells. Also, we proved miR-29b-3p as a negative regulator in cardiac hypertrophy. Finally, miR-29b-3p inhibition abolished the anti-hypertrophy effect of TUG1 depletion in Ang II-treated H9c2 cells. Collectively, our findings confirmed that TUG1 functioned as a positive modulator of cardiac hypertrophy via sponging miR-29b-3p, indicating that TUG1 might serve as a potential target for the treatment of cardiac hypertrophy and even heart failure.

MiR-144 mediates Nrf2 inhibition and alveolar epithelial dysfunction in HIV-1 transgenic rats

Chronic HIV infection causes redox stress and increases the risk of acute and chronic lung injury, even when individuals are adherent to antiretroviral therapy. HIV-1 transgene expression in rats inhibits nuclear factor (erythroid-derived 2)-like 2 (Nrf2), which regulates antioxidant defenses and alveolar epithelial cell (AEC) barrier function, but the mechanism is unknown. In this study, we present novel evidence that these pathological effects of HIV are mediated by microRNA-144 (miR-144). HIV-1 transgene expression in vivo increases the expression of miR-144 in the alveolar epithelium, and this can be replicated by direct exposure of naïve primary AECs to either Tat or gp120 ex vivo. Further, treating naïve primary AECs with a miR-144 mimic decreased the expression and activity of Nrf2 and inhibited their barrier formation. In contrast, treatment with a miR-144 antagomir increased the expression and activity of Nrf2 and improved barrier function in primary AECs isolated from HIV-1 transgenic rats. Importantly, either delivering the miR-144 antagomir intratracheally, or directly activating Nrf2 by dietary treatment with PB123, increased Nrf2 expression and barrier formation in HIV-1 transgenic rat AECs. This study provides new experimental evidence that HIV-induced inhibition of Nrf2 and consequent AEC barrier dysfunction are mediated via miR-144, and that these pathophysiological effects can be mitigated in vivo by either directly antagonizing miR-144 or activating Nrf2. Our findings suggest that targeting the inhibition of Nrf2 in individuals living with HIV could enhance their lung health and decrease the lung-specific morbidity and mortality that persists despite antiretroviral therapy.