LncRNA MIR22HG inhibits growth, migration and invasion through regulating the miR-10a-5p/NCOR2 axis in hepatocellular carcinoma cells

Andrographolide anti-proliferation and metastasis of hepatocellular carcinoma through LncRNA MIR22HG regulation

Hepatocellular carcinoma (HCC) treatment is a major challenge. Although andrographolide (Andro) has an anti-proliferation effect on HCC, its underlying mechanism is not yet elucidated, and whether Andro can inhibit HCC metastasis has not been reported. The present study aimed to clarify whether Andro inhibits SK-Hep-1 cell proliferation and HCC metastasis, and the mechanisms. The results showed that Andro significantly reduced the survival of HCC cells and tumor weight and volume in tumor-bearing nude mice. Andro also triggered apoptosis of HCC cells and upregulated MIR22HG, Cleaved Caspase 9/7/3 expression levels, and downregulated BCL-2 mRNA, BCL-2 expression levels. Knockdown of MIR22HG or overexpression of HuR attenuated the effects of Andro on the signal transduction of mitochondrial apoptotic pathway and proliferation ability in HCC cells. Moreover, Andro significantly reduced the invasive ability of the cells and the level of HCC cell lung metastasis, upregulated miR-22-3p expression level and downregulated HMGB1 and MMP-9 expression levels. MIR22HG or miR-22-3p knockdown attenuated the effects of Andro on the signaling of HMGB1/MMP-9 pathway and invasive ability in HCC cells, while the overexpression of HMGB1 attenuated the inhibitory effects of Andro on the MMP-9 expression level and invasive ability in HCC cells. Thus, the regulation of MIR22HG-HuR/BCL-2 and MIR22HG/HMGB1 signaling pathways is involved in the anti-HCC proliferation and metastasis effects of Andro. This study provided a new pharmacological basis for Andro in HCC treatment and, for the first time, identified a natural product molecule capable of positively regulating MIR22HG, which has a robust biological function.

TGF-β in correlation with tumor progression, immunosuppression and targeted therapy in colorectal cancer

Colorectal cancer (CRC) is a complex malignancy responsible for the second-highest cancer deaths worldwide. TGF-β maintains normal cellular homeostasis by inhibiting the cell cycle and inducing apoptosis, but its elevated level is correlated with colorectal cancer progression, as TGF-β is a master regulator of the epithelial-to-mesenchymal transition, a critical step of metastasis. Tumors, including CRC, use elevated TGF-β levels to avoid immune surveillance by modulating immune cell differentiation, proliferation, and effector function. Presently, the treatment of advanced CRC is mainly based on chemotherapy, with multiple adverse effects. Thus, there is a need to develop alternate tactics because CRC continue to be mostly resistant to the present therapeutic regimen. TGF-β blockade has emerged as a promising therapeutic target in cancer therapy. Blocking TGF-β with phytochemicals and other molecules, such as antisense oligonucleotides, monoclonal antibodies, and bifunctional traps, alone or in combination, may be a safer and more effective way to treat CRC. Furthermore, combination immunotherapy comprising TGF-β blockers and immune checkpoint inhibitors is gaining popularity because both molecules work synergistically to suppress the immune system. Here, we summarize the current understanding of TGF-β as a therapeutic target for managing CRC and its context-dependent tumor-promoting or tumor-suppressing nature.

Long non-coding RNA MIR22HG inhibits the proliferation and migration, and promotes apoptosis by targeting microRNA-9-3p/ SOCS1 axis in small cell lung cancer cells

BACKGROUND

This study aims to determine the role of long non-coding RNA (LncRNA) MIR22HG in small cell lung cancer (SCLC), and to explore its relevant mechanism.

METHODS AND RESULTS

The expressions of genes and proteins in SCLC cells were examined applying qRT-PCR and western blot. Cell proliferation estimation was implemented utilizing cell counting kit-8 (CCK-8) and colony formation assays; the assessment of cell migration and invasion was operated employing Wound healing and Transwell; apoptosis evaluation was conducted adopting flow cytometric assay. Binding relationships was confirmed by luciferase reporter assay. Moreover, SCLC animal model was established to explore the role of MIR22HG in vivo. It was found that MIR22HG was declined and miR-9-3p was elevated in five SCLC cell lines (NCI-H446, NCI-H69, SHP-77, DMS79 and NCI-H345) in comparison with normal human bronchial epithelial cell line (NHBE). More interestingly, overexpression of MIR22HG resulted in decreased cell viability, declined colony formation, diminished capacities of cell migration and invasion in NCI-H446 and NCI-H345 cells but induced more apoptotic cells. However, these impacts were reversed by miR-9-3p upregulation. Meanwhile, MIR22HG could bind to miR-9-3p and negatively regulate its expression in SCLC. What's more, LncRNA MIR22HG overexpression was also testified to elevate SOCS1 via downregulating miR-9-3p expression. Furthermore, in vivo study further confirmed the role of MIR22HG/miR-9-3p in tumor regulation of SCLC.

CONCLUSIONS

In conclusion, MIR22HG in SCLC was found to modulate miR-9-3p level and might act as a possible biomarker for SCLC treatment.

Differentially expressed non-coding RNAs and their regulatory networks in liver cancer

The vast majority of human transcriptome is represented by various types of small RNAs with little or no protein-coding capability referred to as non-coding RNAs (ncRNAs). Functional ncRNAs include microRNAs (miRNAs), long non-coding RNAs (lncRNAs), and circular RNAs (circRNAs), which are expressed at very low, but stable and reproducible levels in a variety of cell types. ncRNAs regulate gene expression due to miRNA capability of complementary base pairing with mRNAs, whereas lncRNAs and circRNAs can sponge miRNAs off their target mRNAs to act as competitive endogenous RNAs (ceRNAs). Each miRNA can target multiple mRNAs and a single mRNA can interact with several miRNAs, thereby creating miRNA-mRNA, lncRNA-miRNA-mRNA, and circRNA-miRNA-mRNA regulatory networks. Over the past few years, a variety of differentially expressed miRNAs, lncRNAs, and circRNAs (DEMs, DELs, and DECs, respectively) have been linked to cancer pathogenesis. They can exert both oncogenic and tumor suppressor roles. In this review, we discuss the recent advancements in uncovering the roles of DEMs, DELs, and DECs and their networks in aberrant cell signaling, cell cycle, transcription, angiogenesis, and apoptosis, as well as tumor microenvironment remodeling and metabolic reprogramming during hepatocarcinogenesis. We highlight the potential and challenges in the use of differentially expressed ncRNAs as biomarkers for liver cancer diagnosis and prognosis.

Prostate Cancer and microRNAs: New insights into Apoptosis

Prostate cancer (PCa) is known as one of the most prevalent malignancies globally and is not yet curable owing to its progressive nature. It has been well documented that Genetic and epigenetic alterations maintain mandatory roles in PCa development. Apoptosis, a form of programmed cell death, has been shown to be involved in a number of physiological processes. Apoptosis disruption is considered as one of the main mechanism involved in lots of pathological conditions, especially malignancy. There is ample of evidence in support of the fact that microRNAs (miRNAs) have crucial roles in several cellular biological processes, including apoptosis. Escaping from apoptosis is a common event in malignancy progression. Emerging evidence revealed miRNAs capabilities to act as apoptotic or anti-apoptotic factors by altering the expression levels of tumor inhibitor or oncogene genes. In the present narrative review, we described in detail how apoptosis dysfunction could be involved in PCa processes and additionally, the mechanisms behind miRNAs affect the apoptosis pathways in PCa. Identifying the mechanisms behind the effects of miRNAs and their targets on apoptosis can provide scientists new targets for PCa treatment.

Advances in targeting of miR‑10‑associated lncRNAs/circRNAs for the management of cancer (Review)

With advancements in sequencing technologies, an increasing number of aberrantly expressed long-non-coding RNAs (lncRNAs) and circular RNAs (circRNAs) have been identified in various types of cancer. lncRNAs and circRNAs are now well-established tumor-influencing factors in cancer, driving not only tumor proliferation and invasion, but also cancer progression, drug resistance and metastatic recurrence. The majority of lncRNAs and circRNAs influence cancer progression by targeting microRNAs (miRNAs/miRs). miR-10a and miR-10b, key members of the miR-10 family, have been shown to play important regulatory roles in cell proliferation, differentiation to cancer progression, and development. Manual evaluation and grouping according to different types of competing endogenous RNA and tumor was performed. The review outlined the current state of knowledge on the regulation of miR-10 family-related lncRNAs and circRNAs. The involvement of lncRNAs and circRNAs in the biogenesis, maturation and function of malignant tumors through the miR-10 family, and the key gene targets and signaling cascades that lncRNAs and circRNAs regulate through the miR-10 family were summarized. Based on the findings of this review, it can be hypothesized that lncRNAs and circRNAs targeting the miR-10 family may serve as diagnostic/prognostic markers and/or therapeutic targets for the management of cancer.

Long non-coding RNAs (lncRNAs) in hepatocellular carcinoma progression: Biological functions and new therapeutic targets

Liver is an important organ in body that performs vital functions such as detoxification. Liver is susceptible to development of cancers, and hepatocellular carcinoma (HCC) is among them. 75-85% of liver cancer cases are related to HCC. Therefore, much attention has been directed towards understanding factors mediating HCC progression. LncRNAs are epigenetic factors with more than 200 nucleotides in length located in both nucleus and cytoplasm and they are promising candidates in cancer therapy. Directing studies towards understanding function of lncRNAs in HCC is of importance. LncRNAs regulate cell cycle progression and growth of HCC cells, and they can also induce/inhibit apoptosis in tumor cells. LncRNAs affect invasion and metastasis in HCC mainly by epithelial-mesenchymal transition (EMT) mechanism. Revealing the association between lncRNAs and downstream signaling pathways in HCC is discussed in the current manuscript. Infectious diseases can affect lncRNA expression in mediating HCC development and then, altered expression level of lncRNA is associated with drug resistance and radio-resistance. Biomarker application of lncRNAs and their role in prognosis and diagnosis of HCC are also discussed to pave the way for treatment of HCC patients.

Exosomes derived from human umbilical cord mesenchymal stem cells protect against papain-induced emphysema by preventing apoptosis through activating VEGF-VEGFR2-mediated AKT and MEK/ERK pathways in rats

Introduction

Chronic obstructive pulmonary disease (COPD) is a leading cause of high mortality and heavy burden in the world. Unfortunately, emphysema, as an important component of COPD, has no curative treatments currently. Recently, human umbilical cord mesenchymal stem cells-derived exosomes (hUCMSC-Ex) constitute a promising alternative approach for tissue regeneration and repair. However, the roles of hUCMSC-Ex in emphysema and its mechanism are largely unknown. Here, we investigated the effect and the action mechanism of hUCMSC-Ex in repairing emphysema induced by papain in rats.

Methods

SD rats were used to establish a papain-induced emphysema model and estimate the effect and mechanism of hUCMSC-Ex treatment. H&E staining and mean linear intercept (MLI) were used to evaluate the hUCMSC-Ex effect on emphysema. Western blotting, TUNEL and miRNA-seq were used to investigate the molecular mechanisms of hUCMSC-Ex treatment in models of papain-induced emphysema.

Results

Papain treatment led to typical emphysema, while hUCMSC-Ex reversed emphysematous changes effectively. Apoptosis of endothelial cells and other types of cells were observed in models, while hUCMSC-Ex effectively prevented their apoptosis. hUCMSC-Ex repressed active caspase-3, activated VEGF-VEGFR2-mediated AKT pathway and MEK/ERK pathway in emphysematous lungs. Notably, several miRNAs, such as hsa-miR-10a-5p and hsa-miR-146a-5p, were target related to the roles of hUCMSC-Ex in papain-induced emphysema through VEGF-VEGFR2-mediated AKT and MEK/ERK pathways.

Conclusions

hUCMSC-Ex effectively rescued the papain-induced emphysema injury through VEGF-VEGFR2-mediated AKT pathway and MEK/ERK pathway.

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Exosomes from human umbilical cord mesenchymal stem cells (hUCMSC-Ex) pro protect against papain-injured emphysema in rats.

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hUCMSC-Ex prevent lung cells apoptosis by activating VEGF-VEGFR2-mediated AKT and MEK/ERK pathways.

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Several miRNAs, such as hsa-miR-10a-5p, were target related to the roles of hUCMSC-Ex.

Wnt/β-Catenin Signaling as a Driver of Stemness and Metabolic Reprogramming in Hepatocellular Carcinoma

Simple Summary

Aberrant Wnt/β-catenin signaling has been reported to play crucial role in pathogenesis of hepatocellular carcinoma (HCC). In this review, we focus on the regulatory role of Wnt/β-catenin signaling in cancer stemness and metabolic reprogramming, which are two emerging hallmarks of cancer. Understanding the role of Wnt/β-catenin signaling in regulation of the above processes reveals novel therapeutic strategy against this deadly disease.

Abstract

Hepatocellular carcinoma (HCC) is a major cause of cancer death worldwide due to its high rates of tumor recurrence and metastasis. Aberrant Wnt/β-catenin signaling has been shown to play a significant role in HCC development, progression and clinical impact on tumor behavior. Accumulating evidence has revealed the critical involvement of Wnt/β-catenin signaling in driving cancer stemness and metabolic reprogramming, which are regarded as emerging cancer hallmarks. In this review, we summarize the regulatory mechanism of Wnt/β-catenin signaling and its role in HCC. Furthermore, we provide an update on the regulatory roles of Wnt/β-catenin signaling in metabolic reprogramming, cancer stemness and drug resistance in HCC. We also provide an update on preclinical and clinical studies targeting Wnt/β-catenin signaling alone or in combination with current therapies for effective cancer therapy. This review provides insights into the current opportunities and challenges of targeting this signaling pathway in HCC.

Function of the Long Noncoding RNAs in Hepatocellular Carcinoma: Classification, Molecular Mechanisms, and Significant Therapeutic Potentials

Hepatocellular carcinoma (HCC) is the most common and serious type of primary liver cancer. HCC patients have a high death rate and poor prognosis due to the lack of clear signs and inadequate treatment interventions. However, the molecular pathways that underpin HCC pathogenesis remain unclear. Long non-coding RNAs (lncRNAs), a new type of RNAs, have been found to play important roles in HCC. LncRNAs have the ability to influence gene expression and protein activity. Dysregulation of lncRNAs has been linked to a growing number of liver disorders, including HCC. As a result, improved understanding of lncRNAs could lead to new insights into HCC etiology, as well as new approaches for the early detection and treatment of HCC. The latest results with respect to the role of lncRNAs in controlling multiple pathways of HCC were summarized in this study. The processes by which lncRNAs influence HCC advancement by interacting with chromatin, RNAs, and proteins at the epigenetic, transcriptional, and post-transcriptional levels were examined. This critical review also highlights recent breakthroughs in lncRNA signaling pathways in HCC progression, shedding light on the potential applications of lncRNAs for HCC diagnosis and therapy.

The Role, Significance, and Association of MicroRNA-10a/b in Physiology of Cancer

MicroRNAs (miRNAs) are small non-coding RNAs that regulate the translation of mRNA and protein, mainly at the posttranscriptional level. Global expression profiling of miRNAs has demonstrated a broad spectrum of aberrations that correlated with several diseases, and miRNA- 10a and miRNA-10b were the first examined miRNAs to be involved in abnormal activities upon dysregulation, including many types of cancers and progressive diseases. It is expected that the same miRNAs behave inconsistently within different types of cancer. This review aims to provide a set of information about our updated understanding of miRNA-10a and miRNA-10b and their clinical significance, molecular targets, current research gaps, and possible future applications of such potent regulators.

MIR22HG Aggravates Oxygen-Glucose Deprivation and Reoxygenation-Induced Cardiomyocyte Injury through the miR-9-3p/SH2B3 Axis

Reperfusion therapy, the standard treatment for acute myocardial infarction (MI), can trigger necrotic death of cardiomyocytes and provoke ischemia/reperfusion (I/R) injury. However, molecular mechanisms that regulate cardiomyocyte death remain largely unknown. The abnormal expression of lncRNA MIR22HG has been found in types of diseases. The current study was aimed at exploring the function and mechanism of MIR22HG in I/R injury. In this study, mouse myocardial cells (HL-1) treated with oxygen-glucose deprivation and reoxygenation (OGD/R) were used as the in vitro models, and myocardial ischemia reperfusion injury (MIRI) animal models in vivo were established in male C57BL/6 mice. Experiments including CCK-8, flow cytometry, TUNEL, HE staining, RT-qPCR, western blotting, and luciferase reporter assays were performed to explore the function and potential mechanism of MIR22HG in MIRI in vitro and in vivo. Bioinformatics analysis was performed to predict the binding site between miR-9-3p and MIR22HG (or SH2B3). Our results indicated that the MIR22HG level was upregulated in cardiomyocytes after OGD/R treatment. The knockdown of MIR22HG promoted cell viability and inhibited apoptosis and extracellular matrix (ECM) production in OGD/R-treated HL-1 cells. In mechanism, MIR22HG binds to miR-9-3p, and miR-9-3p targets the SH2B3 3 ${}^{\prime }$ untranslated region (UTR). Moreover, SH2B3 expression was positively regulated by MIR22HG but negatively modulated by miR-9-3p. Rescue assays suggested that the suppressive effect of MIR22HG knockdown on cell viability, apoptosis, and ECM accumulation was reversed by the overexpression of SH2B3. The in vivo experiments demonstrated that MIR22HG knockdown alleviated cardiomyocyte apoptosis and reduced myocardial infarct size in MIRI mice. In summary, MIR22HG knockdown alleviates myocardial injury through the miR-9-3p/SH2B3 axis.

Long non-coding RNA MIR22HG suppresses cell proliferation and promotes apoptosis in prostate cancer cells by sponging microRNA-9-3p

The present study was designed to discuss long non-coding RNA (lncRNA) MIR22HG expression in prostate cancer and to address its effect on prostate cancer cells. MIR22HG and microRNA (miR)-9-3p expressions in prostate cancer cells were examined with the use of quantitative real-time PCR (qRT-PCR). Cell counting kit (CCK)-8, colony formation, and TUNEL were conducted to determine cell viability and apoptosis. Immunofluorescence was employed for the detection of Ki67 expression, and western blotting was applied for the examination of apoptosis-related proteins. The relationship of MIR22HG and miR-9-3p was verified employing luciferase reporter assay. Indeed, low MIR22HG expression was discovered in prostate cancer cells. Subsequently, in vitro loss-of-function studies revealed that MIR22HG overexpression suppressed cell proliferation but promoted cell apoptosis, accompanied with a reduction in Ki67 and Bcl-2 expressions, as well as an elevation in Bax and cleaved caspase 3 expressions. In addition, MIR22HG was identified as a sponge of miR-9-3p and the impacts of MIR22HG overexpression on cell proliferation and apoptosis were partly hindered by miR-9-3p overexpression. In summary, MIR22HG acts as an anticancer gene in prostate cancer via inhibiting cell proliferation and promoting apoptosis by sponging miR-9-3p. This article may provide a novel insight into the treatment of prostate cancer.

Identification of lncRNA/circRNA-miRNA-mRNA ceRNA Network as Biomarkers for Hepatocellular Carcinoma

Background: Hepatocellular carcinoma (HCC) accounts for the majority of liver cancer, with the incidence and mortality rates increasing every year. Despite the improvement of clinical management, substantial challenges remain due to its high recurrence rates and short survival period. This study aimed to identify potential diagnostic and prognostic biomarkers in HCC through bioinformatic analysis.

Methods: Datasets from GEO and TCGA databases were used for the bioinformatic analysis. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses were carried out by WebGestalt website and clusterProfiler package of R. The STRING database and Cytoscape software were used to establish the protein-protein interaction (PPI) network. The GEPIA website was used to perform expression analyses of the genes. The miRDB, miRWalk, and TargetScan were employed to predict miRNAs and the expression levels of the predicted miRNAs were explored via OncomiR database. LncRNAs were predicted in the StarBase and LncBase while circRNA prediction was performed by the circBank. ROC curve analysis and Kaplan-Meier (KM) survival analysis were performed to evaluate the diagnostic and prognostic value of the gene expression, respectively.

Results: A total of 327 upregulated and 422 downregulated overlapping DEGs were identified between HCC tissues and noncancerous liver tissues. The PPI network was constructed with 89 nodes and 178 edges and eight hub genes were selected to predict upstream miRNAs and ceRNAs. A lncRNA/circRNA-miRNA-mRNA network was successfully constructed based on the ceRNA hypothesis, including five lncRNAs (DLGAP1-AS1, GAS5, LINC00665, TYMSOS, and ZFAS1), six circRNAs (hsa_circ_0003209, hsa_circ_0008128, hsa_circ_0020396, hsa_circ_0030051, hsa_circ_0034049, and hsa_circ_0082333), eight miRNAs (hsa-miR-150-5p, hsa-miR-19b-3p, hsa-miR-23b-3p, hsa-miR-26a-5p, hsa-miR-651-5p, hsa-miR-10a-5p, hsa-miR-214-5p and hsa-miR-486-5p), and five mRNAs (CDC6, GINS1, MCM4, MCM6, and MCM7). The ceRNA network can promote HCC progression via cell cycle, DNA replication, and other pathways. Clinical diagnostic and survival analyses demonstrated that the ZFAS1/hsa-miR-150-5p/GINS1 ceRNA regulatory axis had a high diagnostic and prognostic value.

Conclusion: These results revealed that cell cycle and DNA replication pathway could be potential pathways to participate in HCC development. The ceRNA network is expected to provide potential biomarkers and therapeutic targets for HCC management, especially the ZFAS1/hsa-miR-150-5p/GINS1 regulatory axis.

Integrated analysis of ceRNA network reveals potential prognostic Hint1-related lncRNAs involved in hepatocellular carcinoma progression

Background

Hint1 is a novel tumor suppressor gene, and inactivation of its expression is closely associated with the carcinogenesis of a variety of malignancies. The effects of Hint1 deficiency on the competing endogenous RNA (ceRNA) regulatory network in the context of HCC remains to be fully characterized. This study aims to explore Hint1-related hub lncRNAs in HCC and to establish a reliable prognostic model for HCC patients based on these hub lncRNAs.

Methods

lncRNA + mRNA microarray was used to identify differentially expressed (DE) lncRNAs and mRNAs in Huh7 cells before and after Hint1 knockdown. A Hint1-related ceRNA network was mapped by bioinformation technology. The DEmRNAs in the network were analyzed via GO and KEGG enrichment analyses. Hub DElncRNAs associated with HCC patient prognosis were then detected through univariate and multivariate Cox regression analyses and were incorporated into a prognostic model. The prognostic value of this model was then assessed through the use of Kaplan-Meier curves, time-related ROC analyses, and nomograms. We also utilized Kaplan-Meier curves to validate the relationship between hub lncRNAs and the overall survival (OS) of HCC patients. Finally, A Hint1-related core ceRNA network based on the hub DElncRNAs and DEmRNAs was mapped.

Results

We identified 417 differentially expressed DElncRNAs and 2096 DEmRNAs in Huh7 cells before and after Hint1 knockdown. Three hub DElncRNAs (LINC00324, SNHG3, and DIO3OS) in the Hint1-associated ceRNA network were screened out using univariate and multivariate Cox regression analyses. A hepatocellular carcinoma (HCC) prognostic risk-scoring model and nomogram were constructed using these three hub lncRNAs, and it was confirmed that the risk score of the model could be used as an independent predictor of HCC prognosis. A Hint1-related core ceRNA network based on the hub DElncRNAs and DEmRNAs was also mapped.

Conclusion

We constructed a reliable prognostic model for HCC patients based on three Hint1-related hub lncRNAs, and we believe these three hub lncRNAs may play critical roles in hepatocarcinogenesis, and progression.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12957-022-02535-z.

Reduced NCOR2 expression accelerates androgen deprivation therapy failure in prostate cancer

This study addresses the roles of nuclear receptor corepressor 2 (NCOR2) in prostate cancer (PC) progression in response to androgen deprivation therapy (ADT). Reduced NCOR2 expression significantly associates with shorter disease-free survival in patients with PC receiving adjuvant ADT. Utilizing the CWR22 xenograft model, we demonstrate that stably reduced NCOR2 expression accelerates disease recurrence following ADT, associates with gene expression patterns that include neuroendocrine features, and induces DNA hypermethylation. Stably reduced NCOR2 expression in isogenic LNCaP (androgen-sensitive) and LNCaP-C4–2 (androgen-independent) cells revealed that NCOR2 reduction phenocopies the impact of androgen treatment and induces global DNA hypermethylation patterns. NCOR2 genomic binding is greatest in LNCaP-C4–2 cells and most clearly associates with forkhead box (FOX) transcription factor FOXA1 binding. NCOR2 binding significantly associates with transcriptional regulation most when in active enhancer regions. These studies reveal robust roles for NCOR2 in regulating the PC transcriptome and epigenome and underscore recent mutational studies linking NCOR2 loss of function to PC disease progression.

Long et al. show that reduced levels of NCOR2 lead to accelerated prostate cancer recurrence during androgen withdrawal in a patient-derived xenograft model. NCOR2 reduction is characterized by incomplete response to androgen withdrawal, and recurrent tumors show increased neuroendocrine traits. These phenotypic changes are associated with hypermethylated enhancers.

The role of ceRNA-mediated diagnosis and therapy in hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is one of the leading causes of cancer-related death worldwide due to its high degree of malignancy, high incidence, and low survival rate. However, the underlying mechanisms of hepatocarcinogenesis remain unclear. Long non coding RNA (lncRNA) has been shown as a novel type of RNA. lncRNA by acting as ceRNA can participate in various biological processes of HCC cells, such as tumor cell proliferation, migration, invasion, apoptosis and drug resistance by regulating downstream target gene expression and cancer-related signaling pathways. Meanwhile, lncRNA can predict the efficacy of treatment strategies for HCC and serve as a potential target for the diagnosis and treatment of HCC. Therefore, lncRNA serving as ceRNA may become a vital candidate biomarker for clinical diagnosis and treatment. In this review, the epidemiology of HCC, including morbidity, mortality, regional distribution, risk factors, and current treatment advances, was briefly discussed, and some biological functions of lncRNA in HCC were summarized with emphasis on the molecular mechanism and clinical application of lncRNA-mediated ceRNA regulatory network in HCC. This paper can contribute to the better understanding of the mechanism of the influence of lncRNA-mediated ceRNA networks (ceRNETs) on HCC and provide directions and strategies for future studies.

Long noncoding RNA MIR22HG promotes Leydig cell apoptosis by acting as a competing endogenous RNA for microRNA-125a-5p that targets N-Myc downstream-regulated gene 2 in late-onset hypogonadism

Leydig cells (LCs) apoptosis is responsible for the deficiency of serum testosterone in Late-onset hypogonadism (LOH), while its specific mechanism is still unknown. This study focuses on the role of long noncoding RNA (lncRNA) MIR22HG in LC apoptosis and aims to elaborate its regulatory mechanism. MIR22HG was up-regulated in the testicular tissues of mice with LOH and H2O2-treated TM3 cells (mouse Leydig cell line). Interference of MIR22HG ameliorated cell apoptosis and upregulated miR-125a-5p expression in H2O2-treated TM3 cells. Then, the interaction between MIR22HG and miR-125a-5p was confirmed with RIP and RNA pull-down assay. Further study showed that miR-125a-5p downregulated N-Myc downstream-regulated gene 2 (NDRG2) expression by targeting its 3'-UTR of mRNA. What's more, MIR22HG overexpression aggravated cell apoptosis and reduced testosterone production in TM3 cells via miR-125a-5p/NDRG2 pathway. MIR22HG knockdown elevated testosterone levels in LOH mice. In conclusion, MIR22HG up-regulated NDRG2 expression through targeting miR-125a-5p, thus promoting LC apoptosis in LOH.

The Role of Long Non-Coding RNA and microRNA Networks in Hepatocellular Carcinoma and Its Tumor Microenvironment

Hepatocellular carcinoma (HCC) is a common liver malignancy with high morbidity and poor prognosis. Long non-coding RNAs (lncRNAs) are involved in crucial biological processes of tumorigenesis and progression, and play four major regulatory roles, namely signal, decoy, guide, and scaffold, to regulate gene expression. Through these processes, lncRNAs can target microRNAs (miRNAs) to form lncRNA and miRNA networks, which regulate cancer cell proliferation, metastasis, drug resistance, and the tumor microenvironment. Here, we summarize the multifaceted functions of lncRNA and miRNA networks in the pathogenesis of HCC, the potential use of diagnostic or prognostic biomarkers, and novel therapeutic targets in HCC. This review also highlights the regulatory effects of lncRNA and miRNA networks in the tumor microenvironment of HCC.

Long noncoding RNA Linc01296 promotes hepatocellular carcinoma development through regulation of the miR-26a/PTEN axis

Long noncoding RNA 01296 (Lnc01296) is dysregulated in malignant tumors. However, the detailed effect of Linc01296 on hepatocellular carcinoma (HCC) remains largely unknown. In this study, we identified the biological role of Linc01296 in HCC. The levels of Linc01296 in HCC tissues and a panel of cell lines were assessed by quantitative real-time polymerase chain reaction (qRT-PCR). The effects of Linc01296 on HCC progression were explored using a Cell Counting Kit-8 (CCK-8), flow cytometry, migration and Transwell invasion assays. The interactions among Linc01296, miR-26a and PTEN were determined using luciferase, RNA immunoprecipitation (RIP) and Western blot assays. Tumor xenograft models were utilized to confirm the in vivo functional roles of Linc01296 in HCC development. Linc01296 expression was increased in both HCC tissue samples and cell lines. Knockdown of Linc01296 suppressed HCC cell processes, such as proliferation, migration and invasion, and enhanced apoptosis in vitro; these effects were reversed by a miR-26a mimic or PTEN overexpression. Furthermore, knockdown of Linc01296 suppressed HCC growth in vivo. These findings indicated that Linc01296 is involved in HCC progression via regulating miR-26a/PTEN.

MIR22HG regulates miR-486/PTEN axis in bladder cancer to promote cell proliferation

The tumor suppressive role of MIR22HG has been studied in several types of cancer. We analyzed the TCGA dataset and found the down-regulation of MIR22HG in bladder cancer (BC). Bioinformatics analysis predicted the interaction between MIR22HG and miR-486. The direct interaction between MIR22HG and miR-486 was also confirmed by dual luciferase assay. However, overexpression of these two factors did not significantly affect the expression of each other. Interestingly, overexpression of MIR22HG led to up-regulated phosphatase and tensin homolog (PTEN), which is a target of miR-486. In cell proliferation assay, overexpression of MIR22HG and PTEN led to decreased rates of BC cell proliferation. Moreover, overexpression of miR-486 played an opposite role and attenuated the effects of overexpression of MIR22HG and PTEN. Therefore, MIR22HG regulates miR-486/PTEN axis to promote cell proliferation in BC.

LINC00893 inhibits papillary thyroid cancer by suppressing AKT pathway via stabilizing PTEN

Long non-coding RNAs (lncRNAs) are important to the occurrence and advancement of human cancers. We found through GEPIA that LINC00893 was lowly expressed in thyroid carcinoma (THCA) tissues, whereas the specific functions of LINC00893 has never been reported in PTC. In the current study, we confirmed that LINC00893 was expressed at a low level in PTC cells. Through gain-of-function assays, we determined that LINC00893 overexpression abrogated proliferation and migration abilities of PTC cells. Through signal transduction reporter array we found that LINC00893 potentially modulated the signals of phosphatase and tensin homolog (PTEN)/AKT pathway. In addition, overexpression of LINC00893 increased the expression of PTEN but reduced the levels of phosphorylated AKT in PTC. Additionally, mechanism assays unveiled that LINC00893 stabilized PTEN mRNA via recruiting Fused in sarcoma (FUS) protein. Finally, rescue assays demonstrated that LINC00893 hampered the proliferation and migration of PTC cells via PTEN/AKT pathway. Together, our study first clarified that LINC00893 functions as a tumor suppressor in PTC by blocking AKT pathway through PTEN upregulation.

LncRNA MIR22HG is downregulated in adenomyosis and upregulates miR-2861 through demethylation to inhibit endometrial cell proliferation

AIM

Endometrial cell proliferation plays a critical role in adenomyosis. It has been reported that MIR22HG and miR-2861 play similar roles in regulating endometrial cell proliferation, indicating their involvement in adenomyosis. This study aimed to investigate the potential involvement of MIR22HG and miR-2861 in adenomyosis.

METHODS

Endometrial biopsy was collected from both adenomyosis (n = 45) and the healthy controls (n = 45). The expression of MIR22HG and miR-2861 in biopsies were determined by quantitative reverse transcription polymerase chain reaction (RT-qPCR). The relationship between MIR22HG and miR-2861 in endometrial cells was analyzed by RT-qPCR. Methylation-specific PCR (MSP) was performed to analyze the effects of overexpression of MIR22HG on the expression of miR-2861. Western-blot assays were performed to illustrate the effect of MIR22HG, miR-2861, STAT3, and MMP2 on adenomyosis. Luciferase report assay was performed to analyze the interactions among miR-2861, STAT3, and MMP2. The role of MIR22HG and miR-2861 in regulating the proliferation of endometrial cells was analyzed by cell proliferation assay.

RESULTS

The expression of MIR22HG and miR-2861 in adenomyosis did not change with menstrual cycle. MIR22HG and miR-2861 were significantly downregulated in adenomyosis and they were significantly and positively correlated with each other. In endometrial cells, overexpression of MIR22HG upregulated the expression of miR-2861 and decreased methylation of miR-2861 gene. MIR22HG and miR-2861 downregulated STAT3 and MMP2 to inhibit the proliferation of endometrial cells. In addition, overexpression of both MIR22HG and miR-2861 showed stronger effects.

CONCLUSION

MIR22HG is downregulated in adenomyosis and upregulates miR-2861 through demethylation to inhibit endometrial cell proliferation.

Long Noncoding RNAs in Gastrointestinal Cancer: Tumor Suppression Versus Tumor Promotion

Approximately 80% of the human genome harbors biochemical marks of active transcription that its majority transcribes to noncoding RNAs, namely long noncoding RNAs (lncRNAs). LncRNAs are heterogeneous RNA transcripts that regulate critical biological processes such as cell survival and death. They involve in the progression of different cancers by affecting transcriptional and post-transcriptional modifications as well as epigenetic control of numerous tumor suppressors and oncogenes. Recent findings show that aberrant expression of lncRNAs is associated with tumor initiation, progression, invasion, and overall survival of patients with gastrointestinal (GI) cancers. Some lncRNAs play as tumor suppressors in all GI cancers, but others play as tumor promoters. However, some other lncRNAs might function as a tumor suppressor in one GI cancer, but as a tumor promoter in another GI cancer type. This fact highlights possible context dependency of the expression patterns and roles of at least some lncRNAs in GI cancer development and progression. Here, we review the functional relation of lncRNAs involved in the development and progression of GI cancer by focusing on their roles as tumor suppressor and tumor promoter genes.

MIR22HG Regulates the Proliferation, Epithelial-Mesenchymal Transition, and Apoptosis in Colorectal Carcinoma

Background: Recent investigations have suggested that long noncoding RNA (lncRNA) MIR22HG is commonly dysregulated in multiple types of malignancies. Nevertheless, the roles of MIR22HG in human colorectal carcinoma (CRC) are not well explored. Materials and Methods: Quantitative real-time polymerase chain reaction (qPCR) and in situ hybridization (ISH) assay were used to measure the expression of MIR22HG. 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT), flow cytometry, and migration, as well as invasion assays, were utilized to determine the roles of MIR22HG on growth, apoptosis, migration, and invasiveness of CRC cell. The expression of E-cadherin and N-cadherin was measured using western blotting and immunohistochemistry staining assay. CRC cell growth in vivo was analyzed using nude mice xenograft. Results: The qPCR and ISH assay revealed that MIR22HG was downregulated in CRC sample compared with in normal tissue. MIR22HG was also significantly downexpressed in CRC cells compared with that in normal colonic epithelial cell line. Overexpression of MIR22HG inhibited the growth, migration ability, and invasiveness of CRC cell in vitro. In addition, MIR22HG suppressed the epithelial-mesenchymal transition (EMT) and induced the apoptosis of human CRC cell. Moreover, the authors demonstrated that MIR22HG inhibited the tumor growth of CRC cell and regulated the expression of EMT markers (E-cadherin and N-cadherin) in vivo. Conclusion: Altogether, these results implied that lncRNA MIR22HG restrained the aggressive phenotypes of CRC cell.

Upregulated lncRNA HCG18 in Patients with Non-Alcoholic Fatty Liver Disease and Its Regulatory Effect on Insulin Resistance

PURPOSE

Non-alcoholic fatty liver disease (NAFLD) is a disease associated with genetic-environmental-metabolic stress, which severely damages the liver function of patients. This study aimed to explore the significance and probable functions of HCG18 in NAFLD.

PATIENTS AND METHODS

The expression of HCG18 and miR-197-3p was tested by qRT-PCR. The clinical signification of HCG18 was provided by the ROC curve and Pearson correlation. The corresponding mechanism was punctuated by the luciferase reporter assay and HFD-managed mice.

RESULTS

HCG18 expression was higher in the patients with NAFLD than in controls and in individuals with HOMA-IR score ≥2.5 than those with HOMA-IR score <2.5. HCG18 expression in NAFLD patients was related to BMI, HOMA-IR, ALT, FBG, TC, and TG. HCG18 showed satisfactory predictive accuracy in differentiating NAFLD patients and patients with HOMA-IR ≥2.5. Besides, HCG18 had protective impacts on blood glucose and fat deposition but not on body weight. MiR-197-3p is a direct gene of HCG18, and a reverse correlation was found between miR-197-3p and HCG18. Furthermore, miR-197-3p regulated the influence of HCG18 on insulin resistance and lipid accumulation.

CONCLUSION

Increased levels of HCG18 might be an alternate indicator for NAFLD patients. The HCG18-miR-197-3p axis exerted effects on the progression of fat sedimentation and glucose disorder in NAFLD.

Wnt/β-Catenin Signaling as a Driver of Hepatocellular Carcinoma Progression: An Emphasis on Molecular Pathways

Liver cancers cause a high rate of death worldwide and hepatocellular carcinoma (HCC) is considered as the most common primary liver cancer. HCC remains a challenging disease to treat. Wnt/β-catenin signaling pathway is considered a tumor-promoting factor in various cancers; hence, the present review focused on the role of Wnt signaling in HCC, and its association with progression and therapy response based on pre-clinical and clinical evidence. The nuclear translocation of β-catenin enhances expression level of genes such as c-Myc and MMPs in increasing cancer progression. The mutation of CTNNB1 gene encoding β-catenin and its overexpression can lead to HCC progression. β-catenin signaling enhances cancer stem cell features of HCC and promotes their growth rate. Furthermore, β-catenin prevents apoptosis in HCC cells and increases their migration via triggering EMT and upregulating MMP levels. It is suggested that β-catenin signaling participates in mediating drug resistance and immuno-resistance in HCC. Upstream mediators including ncRNAs can regulate β-catenin signaling in HCC. Anti-cancer agents inhibit β-catenin signaling and mediate its proteasomal degradation in HCC therapy. Furthermore, clinical studies have revealed the role of β-catenin and its gene mutation (CTNBB1) in HCC progression. Based on these subjects, future experiments can focus on developing novel therapeutics targeting Wnt/β-catenin signaling in HCC therapy.

Long non-coding RNA MIR22HG inhibits glioma progression by downregulating microRNA-9/CPEB3

Glioma is one of the most common and aggressive malignant intracranial tumors worldwide. Recently, non-coding RNAs have been found to play critical roles in the development of glioma. However, the exact mechanisms have not been fully elucidated. In the present study, reverse transcription-quantitative PCR was used to determine the expression level of the long non-coding RNA MIR22HG and microRNA (miR)-9, while western blot analysis was used to detect the protein expression level of CPEB3. The potential binding sites were predicted using the StarBase v2.0 online tool and the hypothesis was verified using a luciferase reporter assay. A Cell Counting Kit-8 assay was used to assess cell viability, while wound healing and Matrigel assays were used to determine the migration and invasion ability of glioma cancer cells. The results showed that MIR22HG expression level was decreased but miR-9 expression level was elevated in glioma tissues and cell lines. Furthermore, MIR22HG was found to sponge miR-9, while CPEB3 was the direct target of miR-9 in the glioma cell line. Functionally, MIR22HG regulated the proliferation, invasion and migration of the glioma cell line by targeting miR-9. CPEB3 may be involved in the progression of the glioma cell line. Taken together, these findings confirmed that MIR22HG suppressed glioma development by inhibiting the miR-9/CPEB3 axis and provides a novel therapeutic strategy for glioma treatment.

Construction and analysis of competing endogenous RNA network of MCF-7 breast cancer cells based on the inhibitory effect of 6-thioguanine on cell proliferation

Previous research has proven that 6-thioguanine (6-TG) inhibits the growth of MCF-7 breast cancer cells. Accumulating evidence indicates that long non-coding (lnc)RNAs are involved in the development of various cancer types as competitive endogenous (ce)RNA molecules. The present study was conducted to investigate the regulatory mechanism underlying the function of lncRNAs as ceRNA molecules in MCF-7 cells and to identify more effective prognostic biomarkers for breast cancer treatment. The expression profiles of lncRNAs in untreated MCF-7 cells and 6-TG-treated MCF-7 cells were compared by RNA-seq. The regulatory associations among lncRNAs, micro (mi)RNAs and mRNAs were analyzed and verified by the TargetScan, miRDB and miRTarBas databases. The ceRNA networks were constructed by Cytoscape. The expression levels of two lncRNAs and two miRNAs in the ceRNA network were measured by reverse transcription-quantitative PCR. The OncoLnc and Kaplan-Meier plotter network databases were utilized to determine the effects of lncRNA and miRNA expression on the survival of patients with breast cancer. A ceRNA network was constructed for MCF-7 breast cancer cells treated with 6-TG, and this network may provide valuable information for further research elucidating the molecular mechanism underlying the effects of 6-TG on breast cancer. Moreover, LINC00324, MIR22HG, miR-370-3p and miR-424-5p were identified as potential prognostic and therapeutic biomarkers for breast cancer.

Emerging impact of the long noncoding RNA MIR22HG on proliferation and apoptosis in multiple human cancers

An increasing number of studies have shown that long noncoding RNAs (lncRNAs) play important roles in diverse cellular processes, including proliferation, apoptosis, migration, invasion, chromatin remodeling, metabolism and immune escape. Clinically, the expression of MIR22HG is increased in many human tumors (colorectal cancer, gastric cancer, hepatocellular carcinoma, lung cancer, and thyroid carcinoma), while in others (esophageal adenocarcinoma and glioblastoma), it is significantly decreased. Moreover, MIR22HG has been reported to function as a competitive endogenous RNA (ceRNA), be involved in signaling pathways, interact with proteins and interplay with miRNAs as a host gene to participate in tumorigenesis and tumor progression. In this review, we describe the biological functions of MIR22HG, reveal its underlying mechanisms for cancer regulation, and highlight the potential role of MIR22HG as a novel cancer prognostic biomarker and therapeutic target that can increase the efficacy of immunotherapy and targeted therapy for cancer treatment.

The prognostic significance of long non-coding RNAs in hepatocellular carcinoma: An updated meta-analysis

BACKGROUND

Recently, many studies have demonstrated that long non-coding RNAs (lncRNAs) are abnormally expressed in hepatocellular carcinoma (HCC) and may serve as a potential molecular biomarker to evaluate the prognosis of hepatocellular carcinoma. Therefore, we accomplished a meta-analysis built on current studies to assess the prognostic value of lncRNAs in hepatocellular carcinoma.

METHODS

The PubMed database was carefully searched to collect all eligible studies until February 20, 2019. The pooled hazard ratios (HRs) and 95% confidence intervals (CIs) of the overall survival, relapse-free survival, and progression-free survival were calculated to evaluate the prognostic significance of lncRNAs expression in hepatocellular carcinoma using Stata12.0 software. Heterogeneity, sensitivity analysis, and publication bias were also evaluated.

RESULTS

The results showed that the expression level of lncRNAs was significantly correlated with clinical outcomes. Abnormally expressed lncRNAs predicted poor overall survival (HR=2.19, 95% CI: 1.99-2.42, P<0.001; I²=44.7%, P=0.005), relapse-free survival (HR=2.68, 95% CI: 1.74-4.14, P<0.001; I²=0.0%, P=0.763) and progression-free survival of hepatocellular carcinoma patients (HR=2.44, 95% CI: 1.53-3.89, P<0.001; I²=0.0%, P=0.336). Statistical significance was also noted in subgroup meta-analyses that were stratified by follow-up time, cutoff value, and quality score. Moreover, the pooled results indicated that lncRNAs expression was significantly associated with tumor size (HR=1.48, 95% CI: 1.24-1.79), tumor number (HR=1.34, 95% CI: 1.08-1.66), and tumor node metastasis stage (HR=2.10, 95% CI: 1.48-2.99), but not liver cirrhosis and tumor differentiation (P>0.05).

CONCLUSIONS

This meta-analysis indicates that lncRNAs are strongly associated with prognosis in hepatocellular carcinoma and may serve as a promising indicator for prognostic evaluation of patients with hepatocellular carcinoma. But larger clinical studies are needed to verify its feasibility.

Long noncoding RNA RP11-909N17.2 promotes proliferation, invasion, and migration of hepatocellular carcinoma by regulating microRNA-767-3p

Hepatocellular carcinoma (HCC) is one of the most common causes of cancer-related deaths worldwide, especially in developing countries. Although advances in surgical procedures and targeted medicine have improved the overall survival of patients with HCC, the prognosis is poor. Hence, there is a need to identify novel therapeutic targets for HCC. Here, we report that the expression of RP11-909N17.2, a novel, long, noncoding RNA (lncRNA), is dysregulated in patients with HCC and cell lines. Additionally, this study demonstrated that RP11-909N17.2 facilitates the proliferation and invasion of HCC cells by binding to miRNA-767-3p, a tumor-suppressive microRNA (miRNA). Small integral membrane protein 7 (SMIM7) was identified as the downstream target of miRNA-767-3p. The expression of SMIM7 was upregulated in HCC clinical samples and cell lines. Moreover, SMIM7 was involved in the proliferation and invasion of HCC cells. Furthermore, SMIM7 inhibited the apoptosis of HCC cells, which indicated the oncogenic role of SMIM7 in HCC. The findings of this study suggest that the lncRNA-miRNA-mRNA regulatory axis, which regulates the pathogenesis of HCC, can be a potential novel diagnostic and therapeutic target for HCC.

Restoration of circPSMC3 sensitizes gefitinib-resistant esophageal squamous cell carcinoma cells to gefitinib by regulating miR-10a-5p/PTEN axis

Circular RNAs (circRNAs) has been shown to play an important role in the progression of various cancers. However, the function and underlying mechanisms of circRNAs affecting chemotherapy resistance in esophageal squamous cell carcinoma (ESCC) remain largely unknown. In this study, we used gefitinib-resistant (GR) ESCC cells to investigate the function of circPSMC3 and clarify the underlying mechanism in chemotherapy resistance in ESCC. The results suggested that circPSMC3 expression was downregulated, but miR-10a-5p was upregulated in ESCC tissues and cells, as well as in GR ESCC cells. CircPSMC3 overexpression increased the sensitivity of ESCC cells to gefitinib, as indicated by reduced half maximal inhibitory concentration value, increased apoptosis rate and cleaved caspase-3 protein expression. CircPSMC3 directly interacted with miR-10a-5p and inhibited the expression of miR-10a-5p. Phosphatase and tensin homolog (PTEN) was a direct target of miR-10a-5p and circPSMC3 promoted PTEN expression via decreasing miR-10a-5p level. Moreover, the effect of circPSMC3 on resistance of GR ESCC cells to gefitinib was remarkably reduced by restoration of miR-10a-5p and downregultion of PTEN. Taken together, these observations suggested that upregulation of circPSMC3 overcame resistance of GR ESCC cells to gefitinib by modulating the miR-10a-5p/PTEN axis, which provide a new therapeutic strategy for overcoming gefitinib resistance in ESCC.

Long noncoding RNA LEF1-AS1 acts as a microRNA-10a-5p regulator to enhance MSI1 expression and promote chemoresistance in hepatocellular carcinoma cells through activating AKT signaling pathway

Long noncoding RNAs (lncRNAs) contribute to the development of hepatocellular carcinoma (HCC), which could regulate various HCC biological characteristics. Here, the study seeks to investigate the role of lncRNA LEF1-AS1 in HCC cell chemoresistance by regulating microRNA (miR)-10a-5p and Musashi1 (MSI1). The microarray-based analysis was employed to identify the HCC-related lncRNA-miRNA-gene regulatory network. Expression patterns of LEF1-AS1, miR-10a-5p, and MSI1 in the HCC cell lines, tissues were accessed by means of reverse transcription-quantitative polymerase chain reaction. Next, the interaction among LEF1-AS1, miR-10a-5p, and MSI1 in HCC was accessed by bioinformatics and dual-luciferase reporter gene assay. Then, the cell line resistant to cisplatin was established, which was then treated with sh/oe-lncRNA LEF1-AS1, miR-10a-5p-mimic, and oe/sh-MSI1 vectors alone or in combination. Afterward, the effect of LEF1-AS1, miR-10a-5p, and MSI1 on HCC cell chemoresistance, proliferation, and apoptosis was assessed. At last, in vivo experiments confirmed the role of MSI1 in tumor growth and chemoresistance in HCC. LEF1-AS1 might potentially affect the growth and chemoresistance of HCC cells by regulating miR-10a-5p and MSI1. LEF1-AS1 and MSI1 expression patterns were elevated, while miR-10a-5p was repressed in HCC tissues and cell lines. LEF1-AS1 combined to miR-10a-5p and regulated MSI1, thereby activating the protein kinase B (AKT) signaling pathway. Knockdown of LEF1-AS1 and MSI1 or elevation of miR-10a-5p compromised the proliferation of Huh7 cell line resistant to DDP and promoted its chemosensitivity and apoptosis. At last, these in vitro findings were also confirmed in vivo. Our results unraveled LEF1-AS1 acts as a miR-10a-5p modulator to promote chemoresistance of HCC cells by stimulating MSI1 and activating the AKT signaling pathway, which might provide a novel therapeutic target for HCC.

Role of long noncoding RNA-mediated competing endogenous RNA regulatory network in hepatocellular carcinoma

Long noncoding RNAs (lncRNAs) and microRNAs (miRNAs) are noncoding RNAs (ncRNAs) that occupy over 90% of the human genome, and their main function is to directly or indirectly regulate messenger RNA (mRNA) expression and participate in the tumorigenesis and progression of malignances. In particular, some lncRNAs can interact with miRNAs as competing endogenous RNAs (ceRNAs) to modulate mRNA expression. Accordingly, these RNA molecules are interrelated and coordinate to form a dynamic lncRNA-mediated ceRNA regulatory network. Mounting evidence has revealed that lncRNAs that act as ceRNAs are closely related to tumorigenesis. To date, numerous studies have established many different regulatory networks in hepatocellular carcinoma (HCC), and perturbations in these ceRNA interactions may result in the initiation and progression of HCC. Herein, we emphasize recent advances concerning the biological function of lncRNAs as ceRNAs in HCC, with the aim of elucidating the molecular mechanism underlying these HCC-related RNA molecules and providing novel insights into the diagnosis and treatment of HCC.

Long non-coding RNA MIR22HG promotes osteogenic differentiation of bone marrow mesenchymal stem cells via PTEN/ AKT pathway

Osteoporosis is a prevalent metabolic bone disease characterized by low bone mineral density and degenerative disorders of bone tissues. Previous studies showed the abnormal osteogenic differentiation of endogenous bone marrow mesenchymal stem cells (BMSCs) contributes to the development of osteoporosis. However, the underlying mechanisms by which BMSCs undergo osteogenic differentiation remain largely unexplored. Recently, long non-coding RNAs have been discovered to play important roles in regulating BMSC osteogenesis. In this study, we first showed MIR22HG, which has been demonstrated to be involved in the progression of several cancer types, played an important role in regulating BMSC osteogenesis. We found the expression of MIR22HG was significantly decreased in mouse BMSCs from the osteoporotic mice and it was upregulated during the osteogenic differentiation of human BMSCs. Overexpression of MIR22HG in human BMSCs enhanced osteogenic differentiation, whereas MIR22HG knockdown inhibited osteogenic differentiation both in vitro and in vivo. Mechanistically, MIR22HG promoted osteogenic differentiation by downregulating phosphatase and tensin homolog (PTEN) and therefore activating AKT signaling. Moreover, we found MIR22HG overexpression promoted osteoclastogenesis of RAW264.7 cells, which indicated that MIR22HG played a significant role in bone metabolism and could be a therapeutic target for osteoporosis and other bone-related diseases.

LncRNA MIR22HG abrogation inhibits proliferation and induces apoptosis in esophageal adenocarcinoma cells via activation of the STAT3/c-Myc/FAK signaling

Long non-coding RNAs (lncRNAs) have involved in human malignancies and played an important role in gene regulations. The dysregulation of lncRNA MIR22HG has been reported in several cancers. However, the role of MIR22HG in esophageal adenocarcinoma (EAC) is poorly understood. Loss of function approaches were used to investigate the biological role of MIR22HG in EAC cells. The effects of MIR22HG on cell proliferation were evaluated by WST-1 and colony formation assays. The effects of MIR22HG on cell migration and invasion were examined using transwell assays. QRT-PCR and Western blot were used to evaluate the mRNA and protein expression of related genes. In this study, abrogation of MIR22HG inhibited cell proliferation, colony formation, invasion and migration in EAC 3 cell lines (OE33, OE19 and FLO-1). Mechanistically, MIR22HG silencing decreased the expression of STAT3/c-Myc/p-FAK proteins and induced apoptosis in EAC cell lines. These results delineate a novel mechanism of MIR22HG in EAC, and may provide potential targets by developing lncRNA-based therapies for EAC.

Interfering with long non-coding RNA MIR22HG processing inhibits glioblastoma progression through suppression of Wnt/β-catenin signalling

Long non-coding RNAs play critical roles in tumour progression. Through analysis of publicly available genomic datasets, we found that MIR22HG, the host gene of microRNAs miR-22-3p and miR-22-5p, is ranked among the most dysregulated long non-coding RNAs in glioblastoma. The main purpose of this work was to determine the impact of MIR22HG on glioblastoma growth and invasion and to elucidate its mechanistic function. The MIR22HG/miR-22 axis was highly expressed in glioblastoma as well as in glioma stem-like cells compared to normal neural stem cells. In glioblastoma, increased expression of MIR22HG is associated with poor prognosis. Through a number of functional studies, we show that MIR22HG silencing inhibits the Wnt/β-catenin signalling pathway through loss of miR-22-3p and -5p. This leads to attenuated cell proliferation, invasion and in vivo tumour growth. We further show that two genes, SFRP2 and PCDH15, are direct targets of miR-22-3p and -5p and inhibit Wnt signalling in glioblastoma. Finally, based on the 3D structure of the pre-miR-22, we identified a specific small-molecule inhibitor, AC1L6JTK, that inhibits the enzyme Dicer to block processing of pre-miR-22 into mature miR-22. AC1L6JTK treatment caused an inhibition of tumour growth in vivo. Our findings show that MIR22HG is a critical inducer of the Wnt/β-catenin signalling pathway, and that its targeting may represent a novel therapeutic strategy in glioblastoma patients.

lncRNA TMPO-AS1 Exerts Oncogenic Roles in HCC Through Regulating miR-320a/SERBP1 Axis

Background

Previous evidence have shown that long non-coding RNA (lncRNA) TMPO antisense RNA 1 (TMPO-AS1) is involved in the aggressiveness of several cancers. Nevertheless, the precise functions of TMOP-AS1 in hepatocellular carcinoma (HCC) are still unresolved.

Materials and Methods

The expressions of TMPO-AS1 and miR-320a were detected in HCC tissues and cells by qRT-RCR. The cell growth, migration and invasion were detected by colony formation, wound healing assay and Transwell assay, respectively. The targeting relation between miR-320a and TMPO-AS1 was predicted by bioinformatics analysis and identified by luciferase reporter gene as well as FISH assay. The expression of SERPINE1 MRNA Binding Protein 1 (SERBP1) was detected by Western blot. The growth of HCC cell was analyzed using transplanted tumor model.

Results

Currently, we revealed that TMPO-AS1 was overexpressed in clinical HCC samples and a panel of HCC cell lines. Clinically, a higher level of TMPO-AS1 was connected to the advanced stage of HCC and worse prognosis of patients. Depletion of TMPO-AS1 repressed HCC cell viability, migration ability and invasiveness. Nevertheless, upregulation of TMPO-AS1 caused opposite results. Further studies revealed that lncRNA TMPO-AS1 was largely located in the cytoplasm of HCC cell and sponge miR-320a, resulting in increasing the level of SERBP1 in HCC cell. Finally, TMPO-AS1 silencing suppressed tumor growth of HCC cell in vivo.

Conclusion

Collectively, our results suggested that TMPO-AS1 was a promoting factor for the aggressive behaviors of HCC cell.

MIR22HG acts as a tumor suppressor via TGFβ/SMAD signaling and facilitates immunotherapy in colorectal cancer

Background

Long noncoding RNAs (lncRNAs) are emerging as critical regulatory elements and play fundamental roles in the biology of various cancers. However, we are still lack of knowledge about their expression patterns and functions in human colorectal cancer (CRC).

Methods

Differentially expressed lncRNAs in CRC were identified by bioinformatics screen and the level of MIR22HG in CRC and control tissues were determined by qRT-PCR. Cell viability and migration capacities were examined by MTT and transwell assay. Mouse model was used to examine the function and rational immunotherapy of MIR22HG in vivo.

Results

We systematically investigated the expression pattern of lncRNAs and revealed MIR22HG acts as a tumor suppressor in CRC. The expression of MIR22HG was significantly decreased in CRC, which was mainly driven by copy number deletion. Reduced expression of MIR22HG was significantly associated with poor overall survival. Silencing of MIR22HG promoted cell survival, proliferation and tumor metastasis in vitro and in vivo. Mechanistically, MIR22HG exerts its tumor suppressive activity by competitively interacting with SMAD2 and modulating the activity of TGFβ pathway. Decreased MIR22HG promoted the epithelial-mesenchymal transition in CRC. Importantly, we found that MIR22HG expression is significantly correlated with CD8A and overexpression of MIR22HG triggers T cell infiltration, enhancing the clinical benefits of immunotherapy.

Conclusion

MIR22HG acts as a tumor suppressor in CRC. Our data provide mechanistic insights into the regulation of MIR22HG in TGFβ pathway and facilitates immunotherapy in cancer.

Identification of Potential Prognostic Long Non-Coding RNA Biomarkers for Predicting Recurrence in Patients with Cervical Cancer

Background

Cervical cancer (CC) is one of the most common malignant tumors in women, and its treatment is often accompanied by high recurrence. We aimed to identify the long non-coding RNAs (lncRNAs) associated with CC recurrence.

Methods

We downloaded lncRNAs expression data of CC patients from The Cancer Genome Atlas (TCGA) dataset and used Cox regression models to analyze the lncRNAs relationship with CC recurrence. The significantly associated lncRNAs were utilized to construct a recurrence risk score (RRS) model. Bioinformatics analyses were used to assess the potential role of the critical lncRNAs in CC recurrence. The effect of critical lncRNAs on CC phenotype was determined by in vitro experiments.

Results

Using Cox regression analysis, four lncRNAs, ie, HCG11, CASC15, LINC00189, and LINC00905, were markedly associated with worse recurrence-free survival (RFS) of CC, whereas three lncRNAs, including HULC, LINC00173, and MIR22HG, were the opposite. After constructing the RRS model, Kaplan-Meier analysis revealed that patients with high RRS had significantly increased risk of recurrence. Among the 20 types of tumors in the TCGA database which all had adjacent normal tissues, MIR22HG and HCG11were significantly downregulated in 18 and 10 types of tumors including CC, respectively. Increased MIR22HG was significantly relevant to decreased risks of recurrence among the subgroups of age at diagnosis < 45 (Hazard Ratio (HR) = 0.26), stage I/II (HR = 0.33), T stage I/II (HR = 0.30), chemotherapy (HR = 0.18), and molecular therapy (HR = 0.16). Functionally, elevated MIR22HG expression could suppress CC cell proliferation, migration and invasion.

Conclusion

MIR22HG has a fundamental role in CC recurrence and could be served as a potential prognostic biomarker.

Comprehensive biological function analysis of lncRNAs in hepatocellular carcinoma

Thousands of long non-coding RNAs (lncRNAs) have been discovered in human genomes by gene chip, next-generation sequencing, and/or other methods in recent years, which represent a significant subset of the universal genes involved in a wide range of biological functions. An abnormal expression of lncRNAs is associated with the growth, invasion, and metastasis of various types of human cancers, including hepatocellular carcinoma (HCC), which is an aggressive, highly malignant, and invasive tumor, and a poor prognosis in China. With a more in-depth understanding of lncRNA research for HCC and the emergence of new molecular-targeted therapies, the diagnosis, treatment, and prognosis of HCC will be considerably improved. Therefore, this review is expected to provide recommendations and directions for future lncRNA research for HCC.

miR-10a-5p and miR-29b-3p as Extracellular Vesicle-Associated Prostate Cancer Detection Markers

Extracellular vesicles (EVs) are shed by many different cell types. Their nucleic acids content offers new opportunities for biomarker research in different solid tumors. The role of EV RNA in prostate cancer (PCa) is still largely unknown. EVs were isolated from different benign and malignant prostate cell lines and blood plasma from patients with PCa (n = 18) and controls with benign prostatic hyperplasia (BPH) (n = 7). Nanoparticle tracking analysis (NTA), Western blot, electron microscopy, and flow cytometry analysis were used for the characterization of EVs. Non-coding RNA expression profiling of PC3 metastatic PCa cells and their EVs was performed by next generation sequencing (NGS). miRNAs differentially expressed in PC3 EVs were validated with qRT-PCR in EVs derived from additional cell lines and patient plasma and from matched tissue samples. 92 miRNAs were enriched and 48 miRNAs were depleted in PC3 EVs compared to PC3 cells, which could be confirmed by qRT-PCR. miR-99b-5p was significantly higher expressed in malignant compared to benign EVs. Furthermore, expression profiling showed miR-10a-5p (p = 0.018) and miR-29b-3p (p = 0.002), but not miR-99b-5p, to be overexpressed in plasma-derived EVs from patients with PCa compared with controls. In the corresponding tissue samples, no significant differences in the miRNA expression could be observed. We thus propose that EV-associated miR-10a-5p and miR-29b-3p could serve as potential new PCa detection markers.

Knockdown of miR-10a-5p inhibits gastric cancer cell growth and metastasis by targeting THBS2

BACKGROUND

Many microRNAs (miRNAs) have been found to play a role in inhibiting or promoting the pathogenesis and progression of gastric cancer (GC). However, there are a large number of miRNAs whose roles in GC are still unclear. Therefore, it is still necessary to continue screening miRNAs that affect the growth and metastasis of GC cells.

AIM

To investigate the effect of miR-10a-5p on the growth and metastasis of GC cells and the underlying mechanism.

METHODS

The expression levels of miR-10a-5p in GC tissues and GC cells (MGC-803 and AGS) were detected by real-time quantitative PCR (RT-qPCR). After transfecting miR-10a-5p-inhibitor into MGC-803 and AGS cells, the proliferation, colony formation, migration, and invasion of GC cells were detected by CCK-8 assay, colony formation assay, and transwell assay. The protein and mRNA expression levels of THBS2 in GC tissues and GC cells (MGC-803 and AGS) were detected by Western blot and RT-qPCR, respectively. The potential target genes of miR-10a-5p were predicted with TargetScan software and further verified. After NC + pcDNA-Con, miR-10a-5p inhibitor + pcDNA-Con, or miR-10a-5p inhibitor + pcDNA-THBS2 were co-transfected into MGC-803 cells, the proliferation, colony formation, migration, and invasion of MGC-803 cells were detected by CCK-8 assay, colony formation assay, and transwell assay.

RESULTS

The expression levels of miR-10a-5p were up-regulated in GC tissues as well as MGC-803 and AGS cells. Knockdown of miR-10a-5p significantly decreased the proliferation, colony formation, and migration and invasion of MGC-803 and AGS cells. THBS2 mRNA and protein levels were down-regulated in GC tissues as well as MGC-803 cells and AGS cells. THBS2 was identified to be a target gene of miR-10a-5p. Overexpression of THBS2 could reverse the inhibitory effect of miR-10a-5p knockdown on the proliferation, colony formation, migration, and invasion of MGC-803 cells.

CONCLUSION

Knockdown of miR-10a-5p inhibits the growth and metastasis of GC cells by targeting THBS2.

KCNQ1OT1 aggravates cell proliferation and migration in bladder cancer through modulating miR-145-5p/PCBP2 axis

Background

The large involvement of long non-coding RNAs (LncRNAs) in the biological progression of numerous cancers has been reported. The function of lncRNA KCNQ1OT1 in bladder cancer (BC) remains largely unknown. This study aimed to explore the critical role of KCNQ1OT1 in BC.

Materials and methods

The qRT-PCR was applied to test the expression of RNAs. Cell proliferation was detected by CCK-8 and colony formation assays. Cell apoptosis was measured by TUNEL and flow cytometry experiments. Wound healing and transwell assays were employed to evaluate cell migration and invasion ability respectively. Western blot assay was used to measure relevant protein expression. Immunofluorescence (IF) staining was used to observe EMT process in BC.

Results

KCNQ1OT1 was significantly overexpressed in BC tissue and cell lines. KCNQ1OT1 depletion repressed cell proliferation, migration and invasion, whereas encouraged cell apoptosis. KCNQ1OT1 was a negatively/positively correlated with miR-145-5p/PCBP2 in respect with expression. Mechanically, KCNQ1OT1 was sponge of miR-145-5p and up-regulated the expression of PCBP2. MiR-145-5p inhibition and PCBP2 up-regulation could countervail the tumor-inhibitor role of KCNQ1OT1 knockdown in BC.

Conclusion

KCNQ1OT1 serves as competing endogenous RNA (ceRNA) to up-regulate PCBP2 via sponging miR-145-5p in BC progression.

MicroRNAs in Animal Models of HCC

Hepatocellular carcinoma (HCC) is the second leading cause of cancer-related mortality. Molecular heterogeneity and absence of biomarkers for patient allocation to the best therapeutic option contribute to poor prognosis of advanced stages. Aberrant microRNA (miRNA) expression is associated with HCC development and progression and influences drug resistance. Therefore, miRNAs have been assayed as putative biomarkers and therapeutic targets. miRNA-based therapeutic approaches demonstrated safety profiles and antitumor efficacy in HCC animal models; nevertheless, caution should be used when transferring preclinical findings to the clinics, due to possible molecular inconsistency between animal models and the heterogeneous pattern of the human disease. In this context, models with defined genetic and molecular backgrounds might help to identify novel therapeutic options for specific HCC subgroups. In this review, we describe rodent models of HCC, emphasizing their representativeness with the human pathology and their usefulness as preclinical tools for assessing miRNA-based therapeutic strategies.

MIR22HG As A Tumor Suppressive lncRNA In HCC: A Comprehensive Analysis Integrating RT-qPCR, mRNA-Seq, And Microarrays

Introduction

MIR22HG has a reported involvement in the tumorigenesis of a variety of cancers, including hepatocellular carcinoma (HCC). However, the exact molecular mechanism of MIR22HG in HCC has not been clarified.

Methods

In the present study, we integrated data from in-house RT-qPCR, RNA-sequencing, microarray, and literature studies to conduct a comprehensive evaluation of the clinico-pathological and prognostic significance of MIR22HG in an extremely large group of HCC samples. We also explored the potential mechanism of MIR22HG in HCC by analyzing the alteration profiles of MIR22HG in HCC to predict transcription factors (TFs) that may interact with MIR22HG and to annotate the biological functions of genes co-expressed with MIR22HG. MIR22HG expression was also compared in HCC nude mice xenografts before and after a treatment with nitidine chloride.

Results

We found that MIR22HG was downregulated in HCC and that this downregulation correlated with the malignant phenotype of HCC. Comprehensive analysis of the prognostic impact of MIR22HG in HCC revealed a beneficial effect of MIR22HG on the survival outcome of HCC patients. Seven cases of MIR22HG deep deletion occurred in 360 of the cancer genome atlas (TCGA) provisional HCC samples. A total of 22 MIR22HG-TF-mRNA triplets in HCC were predicted by the lncRNAmap. Co-expressed genes of MIR22HG, identified by weighted correlation network analysis (WGCNA), mainly participated in the pathways involving osteoclast differentiation, chemokine signaling pathways, and hematopoietic cell lineage. In vivo experiments demonstrated that nitidine chloride could stimulate MIR22HG expression in HCC xenografts.

Conclusion

In summary, MIR22HG may play a tumor-suppressive role in HCC by coordinating with predicted TFs and co-expressed genes, such as NLRP3, CSF1R, SIGLEC10, and ZEB2, or by being controlled by nitidine chloride.

The lncRNA SOX2OT rs9839776 C>T Polymorphism Indicates Recurrent Miscarriage Susceptibility in a Southern Chinese Population

Genetic susceptibility may be involved in the onset of recurrent miscarriage. Previous studies have shown that some genetic polymorphisms that regulate cell migration are associated with susceptibility to recurrent miscarriage. The SOX2 overlapping transcript (SOX2OT) may regulate the migration and invasion of multiple tumor cells and is related to susceptibility to various diseases. However, whether lncRNA SOX2OT polymorphisms are related to recurrent miscarriage susceptibility is unclear. Therefore, we investigated the relationship between the lncRNA SOX2OT rs9839776 C>T polymorphism and recurrent miscarriage susceptibility. We recruited 570 subjects with recurrent miscarriage and 578 healthy control subjects from a population in southern China and used the TaqMan method for genotyping. We found a significant association between the rs9839776 CT genotype in the SOX2OT gene and an increased risk for recurrent miscarriage (CT vs CC: adjusted OR = 1.357, 95%CI = 1.065 - 1.728, P = 0.0134). However, we did not observe any significant associations between the recurrent miscarriage risk and the number of miscarriages in different age groups. In conclusion, our study indicated that the rs9839776 CT genotype may contribute to an increased risk of recurrent miscarriage in the southern Chinese population and that rs9839776 may act as a prognostic biomarker in recurrent miscarriage patients. However, an experiment-based study with a larger sample size should be performed to confirm these results.