LncRNA TUG1 functions as a ceRNA for miR-6321 to promote endothelial progenitor cell migration and differentiation

LncRNA H19/miR-107 regulates endothelial progenitor cell pyroptosis and promotes flow recovery of lower extremity ischemia through targeting FADD

BACKGROUND

Peripheral artery disease (PAD) is an ischemic disease with a rising incidence worldwide. The lncRNA H19 (H19) is enriched in endothelial progenitor cells (EPCs), and transplantation of pyroptosis-resistant H19-overexpressed EPCs (oe-H19-EPCs) may promote vasculogenesis and blood flow recovery in PAD, especially with critical limb ischemia (CLI).

METHODS

EPCs isolated from human peripheral blood was characterized using immunofluorescence and flow cytometry. Cell proliferation was determined with CCK8 and EdU assays. Cell migration was assessed by Transwell and wound healing assays. The angiogenic potential was evaluated using tube formation assay. The pyroptosis pathway-related protein in EPCs was detected by western blot. The binding sites of H19 and FADD on miR-107 were analyzed using Luciferase assays. In vivo, oe-H19-EPCs were transplanted into a mouse ischemic limb model, and blood flow was detected by laser Doppler imaging. The transcriptional landscape behind the therapeutic effects of oe-H19-EPCs on ischemic limbs were examined with whole transcriptome sequencing.

RESULTS

Overexpression of H19 in EPCs led to an increase in proliferation, migration, and tube formation abilities. These effects were mediated through pyroptosis pathway, which is regulated by the H19/miR-107/FADD axis. Transplantation of oe-H19-EPCs in a mouse ischemic limb model promoted vasculogenesis and blood flow recovery. Whole transcriptome sequencing indicated significant activation of vasculogenesis pathway in the ischemic limbs following treatment with oe-H19-EPCs.

CONCLUSIONS

Overexpression of H19 increases FADD level by competitively binding to miR-107, leading to enhanced proliferation, migration, vasculogenesis, and inhibition of pyroptosis in EPCs. These effects ultimately promote the recovery of blood flow in CLI.

Endothelial Progenitor Cells: A Review of Molecular Mechanisms in the Pathogenesis and Endovascular Treatment of Intracranial Aneurysms

This comprehensive review explores the multifaceted role of endothelial progenitor cells (EPCs) in vascular diseases, focusing on their involvement in the pathogenesis and their contributions to enhancing the efficacy of endovascular treatments for intracranial aneurysms (IAs). Initially discovered as CD34+ bone marrow-derived cells implicated in angiogenesis, EPCs have been linked to vascular repair, vasculogenesis, and angiogenic microenvironments. The origin and differentiation of EPCs have been subject to debate, challenging the conventional notion of bone marrow origin. Quantification methods, including CD34+ , CD133+ , and various assays, reveal the influence of factors, like age, gender, and comorbidities on EPC levels. Cellular mechanisms highlight the interplay between bone marrow and angiogenic microenvironments, involving growth factors, matrix metalloproteinases, and signaling pathways, such as phosphatidylinositol-3-kinase (PI3K) and mitogen-activated protein kinase (MAPK). In the context of the pathogenesis of IAs, EPCs play a role in maintaining vascular integrity by replacing injured and dysfunctional endothelial cells. Recent research has also suggested the therapeutic potential of EPCs after coil embolization and flow diversion, and this has led the development of device surface modifications aimed to enhance endothelialization. The comprehensive insights underscore the importance of further research on EPCs as both therapeutic targets and biomarkers in IAs.

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.

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.

Long Non-Coding RNAs and Proliferative Retinal Diseases

Retinopathy refers to disorders that affect the retina of the eye, which are frequently caused by damage to the retina's vascular system. This causes leakage, proliferation, or overgrowth of blood vessels through the retina, which can lead to retinal detachment or breakdown, resulting in vision loss and, in rare cases, blindness. In recent years, high-throughput sequencing has significantly hastened the discovery of new long non-coding RNAs (lncRNAs) and their biological functions. LncRNAs are rapidly becoming recognized as critical regulators of several key biological processes. Current breakthroughs in bioinformatics have resulted in the identification of several lncRNAs that may have a role in retinal disorders. Nevertheless, mechanistic investigations have yet to reveal the relevance of these lncRNAs in retinal disorders. Using lncRNA transcripts for diagnostic and/or therapeutic purposes may aid in the development of appropriate treatment regimens and long-term benefits for patients, as traditional medicines and antibody therapy only provide temporary benefits that must be repeated. In contrast, gene-based therapies can provide tailored, long-term treatment solutions. Here, we will discuss how different lncRNAs affect different retinopathies, including age-related macular degeneration (AMD), diabetic retinopathy (DR), central retinal vein occlusion (CRVO), proliferative vitreoretinopathy (PVR), and retinopathy of prematurity (ROP), which can cause visual impairment and blindness, and how these retinopathies can be identified and treated using lncRNAs.

Identification and Verification of a Novel MAGI2-AS3/miRNA-374-5p/FOXO1 Network Associated with HBV-Related HCC

BACKGROUND

Hepatocellular carcinoma (HCC) is a very common neoplasm worldwide, and competitive endogenous RNA (ceRNA) plays an important role in the development of HCC. The purpose of this study is to investigate the molecular mechanisms of ceRNAs in HCC.

METHODS

This study detects potential ceRNAs from HCC through whole genome analysis of lncRNA, miRNA and mRNA expression. We then performed high-throughput sequencing of tissues from five hepatitis B related HCC patients to screen ceRNAs and those screened ceRNAs expressions were verified on tissues from an independent group of six patients. Finally, the function of ceRNAs of interest was illustrated in vitro.

RESULT

Functional and pathway analysis of The Cancer Genome Atlas revealed ceRNA networks. The high-throughput sequencing identified 985 upregulated and 1612 downregulated lncRNAs and 887 upregulated and 1116 downregulated mRNAs in HCC patients. Differentially expressed genes were parallel to cancer-associated processes, comprising 18 upregulated and 35 downregulated significantly enriched pathways including alcoholism and viral carcinogenesis. Among them, a potential ceRNA network was detected and verified in six HCC patients. CeRNAs of the lncRNA MAGI2-AS3/miR-374-5p/FOXO1 pathway were significantly dysregulated in HCC, and validation in vitro showed that FOXO1 is positively regulated by MAGI2-AS3 through the induction of miR-374a/b-5p in HCC cells. In addition, the overexpression of FOXO1 is associated with proliferation, migration, and invasion of HCC cells and increases apoptosis of HCC cells. MiR-374a/b-5p caused an opposite effect by directly suppressing FOXO1 in HCC cells.

CONCLUSION

CeRNA networks were found in HCC and aberrantly expressed ceRNAs of lncRNA MAGI2-AS3/miR-374-5p/FOXO1 plays a crucial role in HCC, assisting in diagnosis and providing a method for treatment.

Taurine-Upregulated Gene 1 Attenuates Cerebral Angiogenesis following Ischemic Stroke in Rats

Objective

Angiogenesis is one of the therapeutic targets of cerebral infarction. Long noncoding RNAs (lncRNAs) can regulate the pathological process of angiogenesis following ischemic stroke. Taurine-upregulated gene 1 (TUG1), an lncRNA, is correlated to ischemic stroke. We intended to determine the effect of TUG1 on angiogenesis following an ischemic stroke.

Materials and Methods

Middle cerebral artery occlusion (MCAO) was adopted to build a focal ischemic model of the rat brain, and pcDNA-TUG1 and miR-26a mimics were injected into rats. Neurological function was estimated through modified neurological severity scores. The volume of focal brain infarction was calculated through 2,3,5-triphenyltetrazolium chloride staining. The level of TUG1 and miR-26a was measured by PCR. The expression of vascular endothelial growth factor (VEGF) and CD31 was checked using immunohistochemistry and western blot. The correlation between miR-26a and TUG1 was verified through a luciferase reporter assay.

Results

TUG1 increased noticeably while miR-26a was markedly reduced in MCAO rats. Overexpression of miR-26a improved neurological function recovery and enhanced cerebral angiogenesis in MCAO rats. TUG1 overexpression aggravated neurological deficits and suppressed cerebral angiogenesis in MCAO rats. Bioinformatics analysis revealed that miR-26a was one of the predicted targets of TUG1. Furthermore, TUG1 combined with miR-26a to regulate angiogenesis. TUG1 overexpression antagonized the role of miR-26a in neurological recovery and angiogenesis in MCAO rats.

Conclusions

TUG1/miR-26a, which may act as a regulatory axis in angiogenesis following ischemic stroke, can be considered a potential target for cerebral infarction therapy.

Long noncoding RNA TUG1 induces angiogenesis of endothelial progenitor cells and dissolution of deep vein thrombosis

Objective

Long non-coding RNA (lncRNA) essentially controls many physiological and pathological processes of deep vein thrombosis (DVT). Based on that, lncRNA taurine upregulated gene 1 (TUG1)-involved angiogenesis of endothelial progenitor cells (EPCs) and dissolution of DVT was explored.

Methods

In the in-vitro experiments, EPCs were engineered with mimic, inhibitor, siRNA, and plasmid, after which tube formation, proliferation, migration, and apoptosis were checked. In the in-vivo experiments, a DVT mouse model was established. Before the DVT operation, the mice were injected with agomir, antagomir, siRNA, and plasmid. Subsequently, thrombosis and damage to the femoral vein were pathologically evaluated. TUG1, miR-92a-3p, and 3-Hydroxy-3-methylglutaryl coenzyme A reductase (Hmgcr) expression in the femoral vein was tested. The relationship between TUG1, miR-92a-3p, and Hmgcr was validated.

Results

DVT mice showed suppressed TUG1 and Hmgcr expression, and elevated miR-92a-3p expression. In EPCs, TUG1 overexpression or miR-92a-3p inhibition promoted cellular angiogenesis, whereas Hmgcr silencing blocked cellular angiogenesis. In DVT mice, elevated TUG1 or inhibited miR-92a-3p suppressed thrombosis and damage to the femoral vein whilst Hmgcr knockdown acted oppositely. In both cellular and animal models, TUG1 overexpression-induced effects could be mitigated by miR-92a-3p up-regulation. Mechanically, TUG1 interacted with miR-92a-3p to regulate Hmgcr expression.

Conclusion

Evidently, TUG1 promotes the angiogenesis of EPCs and dissolution of DVT via the interplay with miR-92a-3p and Hmgcr.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12959-022-00413-y.

TUG1/MAZ/FTH1 Axis Attenuates the Antiglioma Effect of Dihydroartemisinin by Inhibiting Ferroptosis

Glioma is the most common primary intracranial malignant tumor in the brain. Currently, due to the limited treatment methods, the clinical outcome of patients with standard surgery combined with radiotherapy and chemotherapy is not satisfactory. Therefore, we urgently need to develop effective drugs to solve this problem. As a semisynthetic derivative of artemisinin, dihydroartemisinin (DHA) has been proved to have antitumor activity in glioma, which can induce apoptosis and inhibit the proliferation, migration, and invasion of glioma cells. In recent years, ferroptosis has been identified as another antitumor mechanism of DHA. Researchers have shown that DHA could promote ferroptosis in glioma cells. However, the specific molecular mechanisms of ferroptosis induced by DHA need more exploration. In this study, we found DHA could induce ferroptosis with ROS production and lipid peroxidation in glioma cells. Low expression of GPX4 and high expression of HMOX1 were identified in DHA treated glioma cells. Surprisingly, we found FTH1, a negative regulator of ferroptosis, upregulated in DHA treated glioma cells. It indicated that there should be some mechanisms that may cause ferroptosis attenuation in DHA treated glioma cells. For the first time, we confirmed that MYC-associated zinc finger protein (MAZ) could actively regulate FTH1 by binding to FTH1 promoter by CHIP assay. MAZ was further identified as the direct target of long noncoding RNA (lncRNA) TUG1 through luciferase assay. Downregulated expression of TUG1 and upregulated expression of MAZ were identified in DHA treated glioma cells. TUG1 overexpression or inhibition of FTH1 expression could enhance the antiglioma effect of DHA in vitro and in vivo, providing a promising strategy to enhance the antitumor effect of DHA in glioma.

Regulation of Endothelial Progenitor Cell Functions in Ischemic Heart Disease: New Therapeutic Targets for Cardiac Remodeling and Repair

Ischemic heart disease (IHD) is the leading cause of morbidity and mortality worldwide. Ischemia and hypoxia following myocardial infarction (MI) cause subsequent cardiomyocyte (CM) loss, cardiac remodeling, and heart failure. Endothelial progenitor cells (EPCs) are involved in vasculogenesis, angiogenesis and paracrine effects and thus have important clinical value in alternative processes for repairing damaged hearts. In fact, this study showed that the endogenous repair of EPCs may not be limited to a single cell type. EPC interactions with cardiac cell populations and mesenchymal stem cells (MSCs) in ischemic heart disease can attenuate cardiac inflammation and oxidative stress in a microenvironment, regulate cell survival and apoptosis, nourish CMs, enhance mature neovascularization, alleviate adverse ventricular remodeling after infarction and enhance ventricular function. In this review, we introduce the definition and discuss the origin and biological characteristics of EPCs and summarize the mechanisms of EPC recruitment in ischemic heart disease. We focus on the crosstalk between EPCs and endothelial cells (ECs), smooth muscle cells (SMCs), CMs, cardiac fibroblasts (CFs), cardiac progenitor cells (CPCs), and MSCs during cardiac remodeling and repair. Finally, we discuss the translation of EPC therapy to the clinic and treatment strategies.

LncRNA TUG1 Promotes Apoptosis, Invasion, and Angiogenesis of Retinal Endothelial Cells in Retinopathy of Prematurity via MiR-145-5p

Purpose

Retinopathy of prematurity (ROP) is a common retinal vascular disease in premature neonates. In recent years, there is increasing evidence that the long non-coding RNA taurine upregulated gene 1 (TUG1) plays a regulatory role in vascular diseases, suggesting a potential role for TUG1 in vascular endothelial cells. We hypothesized that TUG1 may be associated with ROP. Our aim, therefore, was to explore the biological functions of TUG1 in aberrant retinal development.

Methods

We used the mouse oxygen-induced retinopathy (OIR) model to simulate the pathological changes of retinal in ROP. Quantitative real-time polymerase chain reaction was used to detect the expression of TUG1, miR-145-5p and cellular communication network factor 1 (CCN1). Human retinal endothelial cells (HRECs) were treated with CoCl₂ to mimic hypoxia conditions. Cellular functional changes were observed after transfection with RNA interference (RNAi)-TUG1 and miR-145-5p mimics. The apoptosis of HRECs was detected by flow cytometry, the migration ability was detected by wound healing and transwell migration assays, and the ability of angiogenesis was detected by tube formation assay. The potential binding sites between TUG1, miR-145-5p, and CCN1 were verified by dual-luciferase reporter assays. The degree of retinopathy was evaluated by staining retinal sections with hematoxylin and eosin, and the expression of CCN1, HIF-1α, VEGF, caspase-3, Bcl-2, IL-1β, and TNF-α protein was analyzed by Western blotting and immunohistochemistry.

Results

In the retina tissue of OIR mice, TUG1, miR-145-5p, and CCN1 were differentially expressed. Knocking down TUG1 attenuated apoptosis, migration, and angiogenesis induced by hypoxia on HRECs, as did miR-145-5p overexpression. Results from reporter assays indicate direct interactions between TUG1, miR-145-5p, and CCN1. Intravitreal injection of miR-145-5p mimics reduced the degree of retinopathy.

Conclusion

TUG1 acts as a molecular sponge of miR-145-5p to regulate CCN1 expression and thus regulate the development of retinal neovascularization. This regulatory mechanism may provide a new theoretical basis for the prevention and treatment of ROP.

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.

Long Noncoding RNAs: Recent Insights into Their Role in Male Infertility and Their Potential as Biomarkers and Therapeutic Targets

Long noncoding RNAs (lncRNAs) are composed of nucleotides located in the nucleus and cytoplasm; these are transcribed by RNA polymerase II and are greater than 200 nt in length. LncRNAs fulfill important functions in a variety of biological processes, including genome imprinting, cell differentiation, apoptosis, stem cell pluripotency, X chromosome inactivation and nuclear transport. As high throughput sequencing technology develops, a substantial number of lncRNAs have been found to be related to a variety of biological processes, such as development of the testes, maintaining the self-renewal and differentiation of spermatogonial stem cells, and regulating spermatocyte meiosis. These indicate that lncRNAs can be used as biomarkers and potential therapeutic targets for male infertility. However, only a few comprehensive reviews have described the role of lncRNAs in male reproduction. In this paper, we summarize recent findings relating to the role of lncRNAs in spermatogenesis, their potential as biomarkers for male infertility and the relationship between reproductive arrest and transgenerational effects. Finally, we suggest specific targets for the treatment of male infertility from the perspective of lncRNAs.

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.

MiR-222-3p downregulation prompted the migration, invasion and recruitment of endothelial progenitor cells via ADIPOR1 expression increase-induced AMKP activation

BACKGROUND

Clinical data show that aneurysm rupture causes high mortality in aged men. MicroRNAs (miRNAs) were reported to regulate endothelial progenitor cells (EPCs) which play a vital role in repairing endothelial damage and maintaining vascular integrity. This study identified a novel miRNA regulator for the functions of EPCs in aneurysm repair.

METHODS

Abdominal aortic aneurysm (AAA) model was established on Sprague-Dawley rats which later underwent antagomiR-222 treatment. The histopathological changes of AAA rats were examined by hematoxylin-eosin staining. Flow cytometry was performed to quantify EPCs in peripheral blood and identify EPCs isolated from the rat femur. The potential target of miR-222-3p was predicted by TargetScan v7.2 and validated by Dual-luciferase reporter assay. The effects of miR-222-3p and ADIPOR1 on the migration, invasion and tube formation of EPCs were evaluated by wound healing, Transwell and tube formation assays. The expressions of miR-222-3p and ADIPOR1 in aortic aneurysm tissues and EPCs were assessed by qRT-PCR or Western blot.

RESULTS

AAA exhibited histopathological abnormality, a decreased number of EPCs in the peripheral blood and an increased miR-222-3p expression. AntagomiR-222 injection reversed all these phenomena in AAA rats. Upregulating miR-222-3p expression inhibited the migration, invasion, and tube formation of EPCs, and the expressions of ADIPOR1 and phosphorylated-AMKP, while downregulating miR-222-3p expression exerted opposite effects in EPCs. ADIPOR1 was identified as a target gene of miR-222-3p. Overexpressing ADIPOR1 abrogated the effects of miR-222-3p upregulation on EPCs.

CONCLUSION

Downregulated miR-222-3p prompted the migration, invasion and recruitment of EPCs by targeting ADIPOR1-induced AMKP activation.

New views on endothelial dysfunction in gestational hypertension and potential therapy targets

The placenta has vital roles in metabolite exchange, fetal growth, and pre-eclampsia (PE). In this review, we discuss the pathogenesis of hypertension in pregnancy, focusing on four major theories to explain PE, discussing endothelial roles in those theories. We focus in particular on the roles of nitric oxide (NO) and prostacyclin (PGI₂) in placental endothelium, and propose new hypotheses for the influence and mechanisms of endothelial NO and PGI₂ signaling pathways in PE.

LncRNA influence sequential steps of hepatocellular carcinoma metastasis

As a class of new and crucial molecules involved in the regulation of biological function, long noncoding RNA (lncRNA) have obtained widespread attention in recent days. While it was thought that lncRNA would be redundant in the past, it is proved that lncRNA identify a class of molecular that regulate the homeostasis including hepatocellular carcinoma in the present. All kinds of lncRNA have been implicated in a various of diseases, particularly in tumorigenesis and metastasis. But the mechanisms how they act is still not entirely clear. Metastasis is a major factor affecting long-term survival in hepatocellular carcinoma (HCC) patients. Recently, growing numbers of experiments demonstrate that there is close connection between lncRNA and HCC metastasis. Here, we will briefly introduce a series of steps (primary tumor growth, angiogenesis, epithelial-to-mesenchymal transition, invasion, intravasation, survival in circulatory system, extravasation, dormancy and subsequent secondary tumor growth) of tumor metastasis, its classical but promising theories, the role of lncRNA in metastasis and the possible mechanisms involved. LncRNA, as potentially new and important tumor diagnostic and therapeutic molecules, has attracted much attention in recent years.

Long Noncoding RNA LINC02163 Accelerates Malignant Tumor Behaviors in Breast Cancer by Regulating the MicroRNA-511-3p/HMGA2 Axis

Long intergenic nonprotein-coding RNA 02163 (LINC02163) has been reported to be upregulated and work as an oncogene in gastric cancer. The aims of the present study were to determine the expression profile and clinical value of LINC02163 in breast cancer. Additionally, the detailed functions of LINC02163 in breast cancer were explored, and relevant molecular events were elucidated. In this study, LINC02163 was upregulated in breast cancer, and its expression level was closely associated with tumor size, lymph node metastasis, and TNM stage. Patients with breast cancer presenting high LINC02163 expression exhibited shorter overall survival than those presenting low LINC02163 expression. Knockdown of LINC02163 resulted in a decrease in breast cancer cell proliferation, migration, and invasion and an increase in cell apoptosis in vitro. In addition, silencing of LINC02163 impeded breast cancer tumor growth in vivo. Mechanistic investigation revealed that LINC02163 served as a competing endogenous RNA for microRNA-511-3p (miR-511-3p) and consequently upregulated the expression of the high-mobility group A2 (HMGA2), a downstream target of miR-511-3p. Intriguingly, miR-511-3p inhibition and HMGA2 restoration counteracted the effects of LINC02163 deficiency on the malignant properties of breast cancer cells. LINC02163 exerts cancer-promoting effects during the initiation and progression of breast cancer via regulation of the miR-511-3p/HMGA2 axis. Our findings add to our understanding of the roles of the LINC02163/miR-511-3p/HMGA2 pathway as a regulator of breast cancer pathogenesis and may be useful in the development of lncRNA-directed cancer diagnosis, prognosis, and therapy.

A novel mechanism by which ACTA2-AS1 promotes cervical cancer progression: acting as a ceRNA of miR-143-3p to regulate SMAD3 expression

BACKGROUND

Long non-coding RNAs (LncRNAs) have been increasingly confirmed to be abnormally expressed in human cancer and closely related to tumorigenesis. LncRNA ACTA2-AS1 is abnormally expressed in multiple tumors and participates in their development. However, whether ACTA2-AS1 plays a role in the development of cervical cancer (CC) and the exact mechanism of its role has not been elucidated.

METHODS

Quantitative real-time PCR (qRT-PCR) was conducted to detect the expression level of messenger RNA of ACTA2-AS1, miR-143-3p and SMAD3 in tumor tissues and cells. Additionally, SMAD3 protein expression by western blots in cells. Small interference RNA against ACTA2-AS1 or SMAD3 and miR-143-3p mimic/inhibitor was designed and transfected into CC cell lines to investigate their correlations and potential impacts on cell function. Cell Counting Kit-8 (CCK-8) assay, colony formation, cell cycle assay, transwell assay and flow cytometry analysis were performed to detect the specific effects on cell line proliferation, metastasis and apoptosis.

RESULTS

ACTA2-AS1 was significantly increased in CC tissues and cells and miR-143-3p was down-regulated. Clinically, the higher expression of ACTA2-AS1 was significantly correlated with higher FIGO stage. Loss-of-function assay revealed that silencing of ACTA2-AS1 inhibited cell proliferation, colony formation, migration and promoted apoptosis in CC. Additionally, Pearson correlation analysis showed that the expression of ACTA2-AS1 and miR-143-3p were negatively correlated. Dual-luciferase reporter assay and further mechanistic experiments confirmed that ACTA2-AS1 could sponge and regulate the expression of miR-143-3p. Furthermore, SMAD3 was the target gene of miR-143-3p and ACTA2-AS1 could upregulate SMAD3 through acting as a competitive endogenous RNA (ceRNA) of miR-143-3p. Finally, rescue assay demonstrated that the ACTA2-AS1/miR-143-3p/SMAD3 axis played an important role in the proliferation, migration and apoptosis of CC cells.

CONCLUSIONS

In summary, our study revealed that ACTA2-AS1 upregulates SMAD3 by competitively binding miR-143-3p, thereby accelerating CC progression. The ACTA2-AS1/miR-143-3p/SMAD3 axis can play a crucial role in cervical carcinogenesis, providing new clues for the early diagnosis and treatment of CC.

miR-365b regulates the development of non-small cell lung cancer via GALNT4

Non-small cell lung cancer (NSCLC) is a type of cancer that is associated with high prevalence and high mortality rates in China. Therefore, it is of importance to identify the mechanisms underlying NSCLC progression. In the present study, reverse transcription-quantitative PCR was performed to measure the expression of microRNA (miR)-365b in NSCLC cell lines. In addition, the biological roles of miR-365b and N-acetylgalactosaminyltransferase 4 (GALNT4) were investigated by manipulating the expression levels of miR-365b and GALNT4 in NSCLC cells. It was found that miR-365b expression was reduced in NSCLC tissues and cells. Overexpression of miR-365b inhibited NSCLC cell proliferation whilst promoting apoptosis, but miR-365b knockdown promoted NSCLC cell proliferation. In addition, it was demonstrated that miR-365b regulated the proliferation and apoptosis of NSCLC cells by targeting GALNT4 expression. Collectively, the present study identified a miR-365b/GALNT4 regulatory axis in NSCLC, suggesting that miR-365b may serve as a therapeutic target for NSCLC.

LINC00514 drives osteosarcoma progression through sponging microRNA-708 and consequently increases URGCP expression

Long intergenic nonprotein-coding RNA 00514 (LINC00514) is upregulated in papillary thyroid cancer and contributes to its aggressiveness. In this study, we thoroughly explored the expression profile, specific functions, and relevant molecular mechanism of LINC00514 in osteosarcoma (OS). Herein, LINC00514 was significantly upregulated in OS tissues and cells, and increased LINC00514 expression was closely correlated with tumor size, TNM stage, and distant metastasis. OS patients with high LINC00514 expression had shorter overall survival than those with low LINC00514 expression. LINC00514 interference inhibited OS cell proliferation, colony formation, migration, and invasion in vitro but promoted cell apoptosis and G0/G1 cell cycle arrest. LINC00514 downregulation hindered OS tumor growth in vivo. Mechanistically, LINC00514 functioned as a competing endogenous RNA by directly interacting with microRNA-708-5p (miR-708) and consequently increasing the expression of upregulator of cell proliferation (URGCP). Both miR-708 knockdown and URGCP restoration partially neutralized anticancer activities of LINC00514 silencing in OS cells. LINC00514 increases URGCP expression by acting as a competing endogenous RNA for miR-708, thus exerting oncogenic roles in OS progression. In conclusion, the LINC00514/miR-708/URGCP pathway may be a promising target for drug discovery in the future.