Long non-coding RNA NEAT1 promotes hepatocellular carcinoma cell proliferation through the regulation of miR-129-5p-VCP-IκB

Long non-coding RNA in the regulation of cell death in hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is the predominant form of primary liver cancer, accounting for 90% of all cases. Currently, early diagnosis of HCC can be achieved through serum alpha-fetoprotein detection, B-ultrasound, and computed tomography scanning; however, their specificity and sensitivity are suboptimal. Despite significant advancements in HCC biomarker detection, the prognosis for patients with HCC remains unfavorable due to tumor heterogeneity and limited understanding of its pathogenesis. Therefore, it is crucial to explore more sensitive HCC biomarkers for improved diagnosis, monitoring, and management of the disease. Long non-coding RNA (lncRNA) serves as an auxiliary carrier of genetic information and also plays diverse intricate regulatory roles that greatly contribute to genome complexity. Moreover, investigating gene expression regulation networks from the perspective of lncRNA may provide insights into the diagnosis and prognosis of HCC. We searched the PubMed database for literature, comprehensively classified regulated cell death mechanisms and systematically reviewed research progress on lncRNA-mediated cell death pathways in HCC cells. Furthermore, we prospectively summarize its potential implications in diagnosing and treating HCC.

SOX21-AS1 Augmented Cervical Cancer Growth by Triggering FZD3 to Activate the Wnt/β-Catenin Signaling Pathway

Long non-coding RNA (LncRNA) SOX21-AS1 has been reported that it plays an important role in biological processes of several cancers. However, how it functions in cervical cancer (CC) still remain unclear. This investigation seeks to explore the impact of SOX21-AS1 on CC cell proliferation, invasion and migration and its association to the FZD3 and the Wnt/β-catenin signaling pathway. SOX21-AS1 expression levels were detected using real-time quantitative PCR in 20 cases of cervical cancer together with its adjacent tissues and several cervical cancer cell lines. Transgenic technology and functional experiments were conducted to confirm the carcinogenic properties of SOX21-AS1, and western blot was utilized to analyze the regulatory network composed of SOX21-AS1, FZD3 and the Wnt/β-catenin signaling pathway in CC. Through bioinformatics analysis, we found that the expression of SOX21-AS1 in CC was the highest among 16 kinds of tumor tissues. Moreover, clinical specimens confirmed that both CC tissues and cell lines possessed elevated SOX21-AS1 expressions (P < 0.01). CC cells which stably expressed upregulated SOX21-AS1 were noted to possesses higher rates of metastasis, invasion and proliferation, lower apoptotic rates and higher expression of FZD3,β-catenin and c-myc (P < 0.01). Conversely, the use of small interfering RNA to inhibit the expression of SOX21-AS1 yielded the opposite results (P < 0.01). SOX21-AS1 functions as an oncogenic LncRNA which enhances CC cell metastasis, invasion and proliferation through FZD3 upregulation via Wnt/β-catenin-signaling pathway activation. This LncRNA may represent an important biomarker for CC patients.

Isoform balance of the long noncoding RNA NEAT1 is regulated by the RNA-binding protein QKI, governs the glioma transcriptome, and impacts cell migration

The long noncoding RNA nuclear paraspeckle assembly transcript 1 (NEAT1) is involved in a variety of human cancers. Two overlapping NEAT1 isoforms, NEAT1_1 and NEAT1_2, are produced through mutually exclusive alternative 3' end formation. Previous studies extensively investigated NEAT1 dysregulation in tumors, but often failed to achieve distinct quantification of the two NEAT1 isoforms. Moreover, molecular mechanisms governing the biogenesis of NEAT1 isoforms and the functional impacts of their dysregulation in tumorigenesis remain poorly understood. In this study, we employed an isoform-specific quantification assay and found differential dysregulation of NEAT1 isoforms in patient-derived glioblastoma multiforme cells. We further showed usage of the NEAT1 proximal polyadenylation site (PAS) is a critical mechanism that controls glioma NEAT1 isoform production. CRISPR-Cas9-mediated PAS deletion reduced NEAT1_1 and reciprocally increased NEAT1_2, which enhanced nuclear paraspeckle formation in human glioma cells. Moreover, the utilization of the NEAT1 PAS is facilitated by the RNA-binding protein quaking (QKI), which binds to the proximal QKI recognition elements. Functionally, we identified transcriptomic changes and altered biological pathways caused by NEAT1 isoform imbalance in glioma cells, including the pathway for the regulation of cell migration. Finally, we demonstrated the forced increase of NEAT1_2 upon NEAT1 PAS deletion is responsible for driving glioma cell migration and promoting the expression of genes implicated in the regulation of cell migration. Together, our studies uncovered a novel mechanism that regulates NEAT1 isoforms and their functional impacts on the glioma transcriptome, which affects pathological pathways of glioma, represented by migration.

LncRNA NEAT1 in the pathogenesis of liver-related diseases

Nuclear paraspeckle assembly transcript 1 (NEAT1) is a long noncoding RNA (lncRNA) that is widely expressed in a variety of mammalian cell types. Altered expression levels of the lncRNA NEAT1 have been reported in liver-related disorders including cancer, fatty liver disease, liver fibrosis, viral hepatitis, and hepatic ischemia. lncRNA NEAT1 mostly acts as a competing endogenous RNA (ceRNA) to sponge various miRNAs (miRs) to regulate different functions. In regard to hepatic cancers, the elevated expression of NEAT1 has been reported to have a relation with the proliferation, migration, angiogenesis, apoptosis, as well as epithelial-mesenchymal transition (EMT) of cancer cells. Furthermore, NEAT1 upregulation has contributed to the pathogenesis of other liver diseases such as fibrosis. In this review, we summarize and discuss the molecular mechanisms by which NEAT1 contributes to liver-related disorders including acute liver failure, nonalcoholic fatty liver disease (NAFLD), liver fibrosis, and liver carcinoma, providing novel insights and introducing NEAT1 as a potential therapeutic target in these diseases.

Unraveling NEAT1's complex role in lung cancer biology: a comprehensive review

This review delves into the pivotal role of the long non-coding RNA NEAT1 in cancer biology, particularly in lung cancer (LC). It emphasizes NEAT1's unique subcellular localization and active involvement in gene regulation and chromatin remodeling. The review highlights NEAT1's impact on LC development and progression, including cell processes such as proliferation, migration, invasion, and resistance to therapy, positioning it as a potential diagnostic marker and therapeutic target. The complex web of NEAT1's regulatory interactions with proteins and microRNAs is explored, alongside challenges in targeting it therapeutically. The review concludes optimistically, suggesting future avenues for research and personalized LC therapies, shedding light on NEAT1's crucial role in LC. See also the Graphical abstract(Fig. 1).

Exploring the role of lncrna neat1 knockdown in regulating apoptosis across multiple cancer types: A review

Long non-coding RNAs (lncRNAs) have emerged as pivotal regulators of gene expression, contributing significantly to a diverse range of cellular processes, including apoptosis. One such lncRNA is NEAT1, which is elevated in several types of cancer and aid in cancer growth. However, recent studies have also demonstrated that the knockdown of NEAT1 can inhibit cancer cells proliferation, movement, and infiltration while enhancing apoptosis. This article explores the function of lncRNA NEAT1 knockdown in regulating apoptosis across multiple cancer types. We explore the existing understanding of NEAT1's involvement in the progression of malignant conditions, including its structure and functions. Additionally, we investigate the molecular mechanisms by which NEAT1 modulates the cell cycle, cellular proliferation, apoptosis, movement, and infiltration in diverse cancer types, including acute myeloid leukemia, breast cancer, cervical cancer, colorectal cancer, esophageal squamous cell carcinoma, glioma, non-small cell lung cancer, ovarian cancer, prostate cancer, and retinoblastoma. Furthermore, we review the recent studies investigating the therapeutic potential of NEAT1 knockdown in cancer treatment. Targeting the lncRNA NEAT1 presents a promising therapeutic approach for treating cancer. It has shown the ability to suppress cancer cell proliferation, migration, and invasion while promoting apoptosis in various cancer types.

A New Understanding of Long Non-Coding RNA in Hepatocellular Carcinoma-From m6A Modification to Blood Biomarkers

With recent advancements in biological research, long non-coding RNAs (lncRNAs) with lengths exceeding 200 nucleotides have emerged as pivotal regulators of gene expression and cellular phenotypic modulation. Despite initial skepticism due to their low sequence conservation and expression levels, their significance in various biological processes has become increasingly apparent. We provided an overview of lncRNAs and discussed their defining features and modes of operation. We then explored their crucial function in the hepatocarcinogenesis process, elucidating their complex involvement in hepatocellular carcinoma (HCC). The influential role of lncRNAs within the HCC tumor microenvironment is emphasized, illustrating their potential as key modulators of disease dynamics. We also investigated the significant influence of N6-methyladenosine (m6A) modification on lncRNA function in HCC, enhancing our understanding of both their roles and their upstream regulators. Additionally, the potential of lncRNAs as promising biomarkers was discussed in liver cancer diagnosis, suggesting a novel avenue for future research and clinical application. Finally, our work underscored the dual potential of lncRNAs as both contributors to HCC pathogenesis and innovative tools for its diagnosis. Existing challenges and prospective trajectories in lncRNA research are also discussed, emphasizing their potential in advancing liver cancer research.

LncRNA NEAT1 suppresses cellular senescence in hepatocellular carcinoma via KIF11-dependent repression of CDKN2A

BACKGROUND

Hepatocellular carcinoma (HCC) is the third leading cause of cancer-related deaths worldwide. Therapeutic options for advanced HCC are limited, which is due to a lack of full understanding of pathogenesis. Cellular senescence is a state of cell cycle arrest, which plays important roles in the pathogenesis of HCC. Mechanisms underlying hepatocellular senescence are not fully understood. LncRNA NEAT1 acts as an oncogene and contributes to the development of HCC. Whether NEAT1 modulates hepatocellular senescence in HCC is unknown.

METHODS

The role of NEAT1 and KIF11 in cellular senescence and tumor growth in HCC was assessed both in vitro and in vivo. RNA pulldown, mass spectrometry, Chromatin immunoprecipitation (ChIP), luciferase reporter assays, RNA FISH and immunofluorescence (IF) staining were used to explore the detailed molecular mechanism of NEAT1 and KIF11 in cellular senescence of HCC.

RESULTS

We found that NEAT1 was upregulated in tumor tissues and hepatoma cells, which negatively correlated with a senescence biomarker CDKN2A encoding p16INK4a and p14ARF proteins. NEAT1 was reduced in senescent hepatoma cells induced by doxorubicin (DOXO) or serum starvation. Furthermore, NEAT1 deficiency caused senescence in cultured hepatoma cells, and protected against the progression of HCC in a mouse model. During senescence, NEAT1 translocated into cytosol and interacted with a motor protein KIF11, resulting in KIF11 protein degradation and subsequent increased expression of CDKN2A in cultured hepatoma cells. Furthermore, KIF11 knockdown caused senescence in cultured hepatoma cells. Genetic deletion of Kif11 in hepatocytes inhibited the development of HCC in a mouse model.

CONCLUSIONS

Conclusively, NEAT1 overexpression reduces senescence and promotes tumor progression in HCC tissues and hepatoma cells, whereas NEAT1 deficiency causes senescence and inhibits tumor progression in HCC. This is associated with KIF11-dependent repression of CDKN2A. These findings lay the foundation to develop potential therapies for HCC by inhibiting NEAT1 and KIF11 or inducing senescence.

Increased age, bilirubin, international normalized ratio, and creatinine score to triglyceride ratio are associated with alcohol-associated primary liver carcinoma: a single-centered retrospective study

BACKGROUND

This study analyzed the clinical features and biomarkers of alcohol-associated liver disease (ALD) to investigate the diagnostic value of age, bilirubin, international normalized ratio (INR), and creatinine (ABIC) score to triglyceride (TG) ratio (ABIC/TG) in ALD-associated primary liver carcinoma (PLC).

MATERIALS AND METHODS

Data were collected from 410 participants with ALD, and the epidemiological and clinical records of 266 participants were analyzed. Participants were divided into ALD-without-PLC and ALD-associated-PLC groups. Relationships between clinical characteristics, biomarkers and ALD-associated PLC were estimated. Serum lipid levels and liver function were compared between ALD patients without PLC and patients with ALD-associated PLC. Scoring systems were calculated to investigate ALD severity. The robustness of the relationship was analyzed by the receiver operating characteristic (ROC) curve.

RESULTS

Age and dyslipidemia were more strongly associated with ALD-associated PLC than with ALD-without PLC, with AORs of 2.39 and 0.25, respectively, with P less than 0.05. Drinking time and average daily intake, ABIC score, and ABIC/TG ratio were significantly higher in the ALD-associated-PLC group than in the ALD-without-PLC group. The AUC for the ABIC/TG ratio predicting the incidence of PLC was 0.80 (P < 0.01), which was higher than that of the ABIC and TG scores alone; additionally, the specificity and Youden index for the ABIC/TG ratio were also higher, and the cutoff value was 6.99.

CONCLUSIONS

In ALD patients, age, drinking time, and average daily intake were risk factors for PLC. Drinking time, average daily intake, TG and ABIC score have diagnostic value for ALD-associated PLC. The ABIC/TG ratio had a higher AUC value and Youden index than the ABIC score and TG level.

Genetic disruption of mammalian endoplasmic reticulum-associated protein degradation: Human phenotypes and animal and cellular disease models

Endoplasmic reticulum-associated protein degradation (ERAD) is a stringent quality control mechanism through which misfolded, unassembled and some native proteins are targeted for degradation to maintain appropriate cellular and organelle homeostasis. Several in vitro and in vivo ERAD-related studies have provided mechanistic insights into ERAD pathway activation and its consequent events; however, a majority of these have investigated the effect of ERAD substrates and their consequent diseases affecting the degradation process. In this review, we present all reported human single-gene disorders caused by genetic variation in genes that encode ERAD components rather than their substrates. Additionally, after extensive literature survey, we present various genetically manipulated higher cellular and mammalian animal models that lack specific components involved in various stages of the ERAD pathway.

An updated review of contribution of long noncoding RNA-NEAT1 to the progression of human cancers

Long non-coding RNAs (lncRNAs) present pivotal roles in cancer tumorigenesis and progression. Recently, nuclear paraspeckle assembly transcript 1 (NEAT1) as a lncRNA has been shown to mediate cell proliferation, migration, and EMT in tumor cells. NEAT1 by targeting several miRNAs/mRNA axes could regulate cancer cell behavior. Therefore, NEAT1 may function as a potent biomarker for the prediction and treatment of some human cancers. In this review, we summarized various NEAT1-related signaling pathways that are critical in cancer initiation and progression.

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.

Distinct binding pattern of EZH2 and JARID2 on RNAs and DNAs in hepatocellular carcinoma development

Hepatocellular carcinoma (HCC) is one of the most malignant cancers worldwide, with high mortality. However, the molecular regulatory mechanisms of liver cancer, especially transcriptional and post-transcriptional mechanisms, should be further studied. Here we used chromatin and cross-linking immunoprecipitation with high throughput sequencing methods (ChIP-seq and CLIP-seq) to capture the global binding profiles on RNAs and DNAs of Enhancer of zeste homolog 2 (EZH2) and its partner Jumonji And AT-Rich Interaction Domain Containing 2 (JARID2) in liver carcinoma cell lines (HepG2) and normal liver cell line (THLE-2), respectively. We also integrated HCC transcriptome data from the TCGA to analyze the expression pattern of bound genes. We found that EZH2 and JARID2 both showed distinct binding profiles between HepG2 and THLE-2 cells. By binding to the primary RNAs, bound transcripts of EZH2 and JARID2 in HepG2 showed significantly increased transcriptional levels in HCC patients. By performing gene set enrichment analysis (GSEA), the bound transcripts were also highly related to HCC development. We also found EZH2 and JARID2 could specifically bind to several long noncoding RNAs (lncRNAs), including H19. By exploring the DNA binding profile, we detected a dramatically repressed DNA binding ability of EZH2 in HepG2 cells. We also found that the EZH2-bound genes showed slightly increased transcriptional levels in HepG2 cells. Integrating analysis of the RNA and DNA binding profiles suggests EZH2 and JARID2 shift their binding ability from DNA to RNA in HepG2 cells to promote cancer development in HCC. Our study provided a comprehensive and distinct binding profile on RNAs and DNAs of EZH2 and JARID2 in liver cancer cell lines, suggesting their potential novel functional manners to promote HCC development.

LncRNA NEAT1 regulates HCV-induced Hepatocellular carcinoma by modulating the miR-9-BGH3 axis

Chronic hepatitis C virus (HCV) infection is a leading cause of end-stage liver diseases, such as fibrosis, cirrhosis and hepatocellular carcinoma (HCC). Several cellular entities, including paraspeckles and their related components, are involved in viral pathogenesis and cancer progression. NEAT1 lncRNA is a major component of paraspeckles that has been linked to several malignancies. In this study, analysis of the Cancer Genome Atlas (TCGA) database and validation in HCV-induced HCC tissue and serum samples showed significantly high expression of NEAT1 in patients with liver cancer. Moreover, we found that NEAT1 levels increased upon HCV infection. To further understand the mechanism of NEAT1-induced HCC progression, we selected one of its targets, miR-9-5 p, which regulates BGH3 mRNA levels. Interestingly, miR-9-5 p levels were downregulated upon HCV infection, whereas BGH3 levels were upregulated. Additionally, partial NEAT1 knockdown increased miR-9-5 p levels and decreased BGH3 levels, corroborating our initial results. BGH3 levels were also upregulated in HCV-induced HCC and TCGA tissue samples, which could be directly correlated with NEAT1 levels. As a known oncogene, BGH3 is directly linked to HCC progression mediated by NEAT1. We also found that NEAT1 levels remained upregulated in serum samples from patients treated with direct-acting antivirals (DAA), indicating that NEAT1 might be a molecular trigger that promotes HCC development. Collectively, these findings provide molecular insights into HCV-induced HCC progression via the NEAT1-miR-9-BGH3 axis.

The Implications of Noncoding RNAs in the Evolution and Progression of Nonalcoholic Fatty Liver Disease (NAFLD)-Related HCC

Nonalcoholic fatty liver disease (NAFLD) is the most prevalent liver pathology worldwide. Meanwhile, liver cancer represents the sixth most common malignancy, with hepatocellular carcinoma (HCC) as the primary, most prevalent subtype. Due to the rising incidence of metabolic disorders, NAFLD has become one of the main contributing factors to HCC development. However, although NAFLD might account for about a fourth of HCC cases, there is currently a significant gap in HCC surveillance protocols regarding noncirrhotic NAFLD patients, so the majority of NAFLD-related HCC cases were diagnosed in late stages when survival chances are minimal. However, in the past decade, the focus in cancer genomics has shifted towards the noncoding part of the genome, especially on the microRNAs (miRNAs) and long noncoding RNAs (lncRNAs), which have proved to be involved in the regulation of several malignant processes. This review aims to summarize the current knowledge regarding some of the main dysregulated, noncoding RNAs (ncRNAs) and their implications for NAFLD and HCC development. A central focus of the review is on miRNA and lncRNAs that can influence the progression of NAFLD towards HCC and how they can be used as potential screening tools and future therapeutic targets.

Molecular Interactions of the Long Noncoding RNA NEAT1 in Cancer

As one of the best-studied long noncoding RNAs, nuclear paraspeckle assembly transcript 1 (NEAT1) plays a pivotal role in the progression of cancers. NEAT1, especially its isoform NEAT1-1, facilitates the growth and metastasis of various cancers, excluding acute promyelocytic leukemia. NEAT1 can be elevated via transcriptional activation or stability alteration in cancers changing the aggressive phenotype of cancer cells. NEAT1 can also be secreted from other cells and be delivered to cancer cells through exosomes. Hence, elucidating the molecular interaction of NEAT1 may shed light on the future treatment of cancer. Herein, we review the molecular function of NEAT1 in cancer progression, and explain how NEAT1 interacts with RNAs, proteins, and DNA promoter regions to upregulate tumorigenic factors.

Regulatory Roles of Noncoding RNAs in the Progression of Gastrointestinal Cancers and Health Disparities

Annually, more than a million individuals are diagnosed with gastrointestinal (GI) cancers worldwide. With the advancements in radio- and chemotherapy and surgery, the survival rates for GI cancer patients have improved in recent years. However, the prognosis for advanced-stage GI cancers remains poor. Site-specific GI cancers share a few common risk factors; however, they are largely distinct in their etiologies and descriptive epidemiologic profiles. A large number of mutations or copy number changes associated with carcinogenesis are commonly found in noncoding DNA regions, which transcribe several noncoding RNAs (ncRNAs) that are implicated to regulate cancer initiation, metastasis, and drug resistance. In this review, we summarize the regulatory functions of ncRNAs in GI cancer development, progression, chemoresistance, and health disparities. We also highlight the potential roles of ncRNAs as therapeutic targets and biomarkers, mainly focusing on their ethnicity-/race-specific prognostic value, and discuss the prospects of genome-wide association studies (GWAS) to investigate the contribution of ncRNAs in GI tumorigenesis.

NEAT1 can be a diagnostic biomarker in the breast cancer and gastric cancer patients by targeting XIST, hsa-miR-612, and MTRNR2L8: integrated RNA targetome interaction and experimental expression analysis

Background

The most frequent malignancy in women is breast cancer (BC). Gastric cancer (GC) is also the leading cause of cancer-related mortality. Long non-coding RNAs (lncRNAs) are thought to be important neurotic regulators in malignant tumors. In this study, we aimed to evaluate the expression level of NEAT1 and the interaction of this non-coding RNA with correlated microRNAs, lncRNAs, and mRNAs or protein coding genes, experimentally and bioinformatically.

Methods

For the bioinformatics analyses, we performed RNA-RNA and protein–protein interaction analyses, using ENCORI and STRING. The expression analyses were performed by five tools: Microarray data analysis, TCGA data analysis (RNA-seq, R Studio), GEPIA2, ENCORI, and real-time PCR experiment. qRT-PCR experiment was performed on 50 GC samples and 50 BC samples, compared to adjacent control tissue.

Results

Based on bioinformatics and experimental analyses, lncRNA NEAT1 have a significant down-regulation in the breast cancer samples with tumor size lower than 2 cm. Also, it has a significant high expression in the gastric cancer patients. Furthermore, NEAT1 have a significant interaction with XIST, hsa-miR-612 and MTRNR2L8. High expression of NEAT1 have a correlation with the lower survival rate of breast cancer samples and higher survival rate of gastric cancer patients.

Conclusion

This integrated computational and experimental investigation revealed some new aspects of the lncRNA NEAT1 as a potential prognostic biomarker for the breast cancer and gastric cancer samples. Further investigations about NEA1 and correlated mRNAs, lncRNAs, and microRNAs – specially the mentioned RNAs in this study – can lead the researchers to more clear information about the role of NEAT1 in the breast cancer and gastric cancer.

Long non-coding RNAs and microRNAs as crucial regulators in cardio-oncology

Cancer is one of the leading causes of morbidity and mortality worldwide. Significant improvements in the modern era of anticancer therapeutic strategies have increased the survival rate of cancer patients. Unfortunately, cancer survivors have an increased risk of cardiovascular diseases, which is believed to result from anticancer therapies. The emergence of cardiovascular diseases among cancer survivors has served as the basis for establishing a novel field termed cardio-oncology. Cardio-oncology primarily focuses on investigating the underlying molecular mechanisms by which anticancer treatments lead to cardiovascular dysfunction and the development of novel cardioprotective strategies to counteract cardiotoxic effects of cancer therapies. Advances in genome biology have revealed that most of the genome is transcribed into non-coding RNAs (ncRNAs), which are recognized as being instrumental in cancer, cardiovascular health, and disease. Emerging studies have demonstrated that alterations of these ncRNAs have pathophysiological roles in multiple diseases in humans. As it relates to cardio-oncology, though, there is limited knowledge of the role of ncRNAs. In the present review, we summarize the up-to-date knowledge regarding the roles of long non-coding RNAs (lncRNAs) and microRNAs (miRNAs) in cancer therapy-induced cardiotoxicities. Moreover, we also discuss prospective therapeutic strategies and the translational relevance of these ncRNAs.

Recent advances of NEAT1-miRNA interactions in cancer

With high incidence rate, cancer is the main cause of death in humans. Non-coding RNAs, as novel master regulators, especially long non-coding RNAs (lncRNAs) and microRNAs (miRNAs), play important roles in the regulation of tumorigenesis. lncRNA NEAT1 has recently gained much attention, as it is dysregulated in a broad spectrum of cancers, where it acts as either an oncogene or a tumor suppressor gene. Accumulating evidence shows that NEAT1 is correlated with the process of carcinogenesis, including proliferation, invasion, survival, drug resistance, and metastasis. NEAT1 is considered to be a biomarker and a novel therapeutic target for the diagnosis and prognosis of different cancer types. The mechanisms by which NEAT1 plays a critical role in cancers are mainly via interactions with miRNAs. NEAT1-miRNA regulatory networks play significant roles in tumorigenesis, which has attracted much attention from researchers around the world. In this review, we summarize the interaction of NEAT1 with miRNAs in the regulation of protein-coding genes in cancer. A better understanding of the NEAT1-miRNA interactions in cancer will help develop new diagnostic biomarkers and therapeutic approaches.

The Crosstalk Between Regulatory Non-Coding RNAs and Nuclear Factor Kappa B in Hepatocellular Carcinoma

Hepatocellular carcinoma (HCC) is a highly lethal type of malignancies that possesses great loss of life safety to human beings worldwide. However, few effective means of curing HCC exist and its specific molecular basis is still far from being fully elucidated. Activation of nuclear factor kappa B (NF-κB), which is often observed in HCC, is considered to play a significant part in hepatocarcinogenesis and development. The emergence of regulatory non-coding RNAs (ncRNAs), particularly microRNAs (miRNAs) and long non-coding RNAs (lncRNAs), is a defining advance in cancer biology, and related research in this branch has yielded many diagnostic and therapeutic opportunities. Recent studies have suggested that regulatory ncRNAs act as inhibitors or activators in the initiation and progression of HCC by targeting components of NF-κB signaling or regulating NF-κB activity. In this review, we attach importance to the role and function of regulatory ncRNAs in NF-κB signaling of HCC and NF-κB-associated chemoresistance in HCC, then propose future research directions and challenges of regulatory ncRNAs mediated-regulation of NF-κB pathway in HCC.

Heterogeneous graph attention network based on meta-paths for lncRNA-disease association prediction

MOTIVATION

Discovering long noncoding RNA (lncRNA)-disease associations is a fundamental and critical part in understanding disease etiology and pathogenesis. However, only a few lncRNA-disease associations have been identified because of the time-consuming and expensive biological experiments. As a result, an efficient computational method is of great importance and urgently needed for identifying potential lncRNA-disease associations. With the ability of exploiting node features and relationships in network, graph-based learning models have been commonly utilized by these biomolecular association predictions. However, the capability of these methods in comprehensively fusing node features, heterogeneous topological structures and semantic information is distant from optimal or even satisfactory. Moreover, there are still limitations in modeling complex associations between lncRNAs and diseases.

RESULTS

In this paper, we develop a novel heterogeneous graph attention network framework based on meta-paths for predicting lncRNA-disease associations, denoted as HGATLDA. At first, we conduct a heterogeneous network by incorporating lncRNA and disease feature structural graphs, and lncRNA-disease topological structural graph. Then, for the heterogeneous graph, we conduct multiple metapath-based subgraphs and then utilize graph attention network to learn node embeddings from neighbors of these homogeneous and heterogeneous subgraphs. Next, we implement attention mechanism to adaptively assign weights to multiple metapath-based subgraphs and get more semantic information. In addition, we combine neural inductive matrix completion to reconstruct lncRNA-disease associations, which is applied for capturing complicated associations between lncRNAs and diseases. Moreover, we incorporate cost-sensitive neural network into the loss function to tackle the commonly imbalance problem in lncRNA-disease association prediction. Finally, extensive experimental results demonstrate the effectiveness of our proposed framework.

Valosin-Containing Protein (VCP)/p97: A Prognostic Biomarker and Therapeutic Target in Cancer

Valosin-containing protein (VCP)/p97, a member of the AAA+ ATPase family, is a molecular chaperone recruited to the endoplasmic reticulum (ER) membrane by binding to membrane adapters (nuclear protein localization protein 4 (NPL4), p47 and ubiquitin regulatory X (UBX) domain-containing protein 1 (UBXD1)), where it is involved in ER-associated protein degradation (ERAD). However, VCP/p97 interacts with many cofactors to participate in different cellular processes that are critical for cancer cell survival and aggressiveness. Indeed, VCP/p97 is reported to be overexpressed in many cancer types and is considered a potential cancer biomarker and therapeutic target. This review summarizes the role of VCP/p97 in different cancers and the advances in the discovery of small-molecule inhibitors with therapeutic potential, focusing on the challenges associated with cancer-related VCP mutations in the mechanisms of resistance to inhibitors.

Targeting Long Non-Coding RNAs in Hepatocellular Carcinoma: Progress and Prospects

Hepatocellular carcinoma is the fifth-ranked cancer worldwide with a relatively low five-year survival rate. Long non-coding RNAs are a group of RNAs with remarkable aberrant expression which could act on multiple bioprocesses and ultimately impact upon tumor proliferation, invasion, migration, metastasis, apoptosis, and therapy resistance in cancer cells including hepatocellular carcinoma cells. In recent years, long non-coding RNAs have been reported to be indispensable targets in clinical target therapy to stop the growth of cancer and prolong the lifespan of patients with hepatocellular carcinoma. In this review, we enumerate the signaling pathways and life activities affected by long non-coding RNAs in hepatocellular carcinoma cells to illustrate the role of long non-coding RNAs in the development and therapy resistance of hepatocellular carcinoma.

Circulating Long Non-Coding RNA GAS5: A Non-Invasive Molecular Marker for Prognosis, Response to Treatment and Survival in Non-Small Cell Lung Cancer

Circulating long non-coding RNAs (lncRNA) are dysregulated in several diseases, especially cancers, e.g. non-small-cell lung cancer (NSCLC). Of specific notice in this regard is growth arrest-specific 5 gene (lncRNA GAS5), which is principally recognised as a tumor suppressor gene in numerous cancers. Functionally, GAS5 is involved in arresting cellular growth and induction of apoptosis. We analysed plasma GAS5 expression by qRT-PCR in 100 patients with NSCLC before and after tumour resection surgery. We reported a downregulation of GAS5 expression in NSCLC tissue and plasma, which showed elevation after surgery. Downregulation of GAS5 was associated with poor prognosis of NSCLC patients.

Elevated miR-129-5p attenuates hepatic fibrosis through the NF-κB signaling pathway via PEG3 in a carbon CCl4 rat model

Hepatic fibrosis is a reversible scaring response to chronic liver injury. MicroRNA (miR)-129-5p might regulate fibrosis-related gene expression. This study is performed to decipher, potential of miR-129-5p to influence the progression of hepatic fibrosis in a carbon tetrachloride (CCl4) rat model. Rat hepatic fibrosis was successfully established by subcutaneous injection of 50% CCl4. RT-qPCR revealed that miR-129-5p was poorly expressed and PEG3 was highly expressed in hepatic fibrosis tissues. As reflected by dual-luciferase reporter gene assay, miR-129-5p targeted and reduced the expression of PEG3. Thereafter, miR-129-5p antagomir or short hairpin RNA against paternally expressed gene 3 (PEG3) was adopted for gain- and loss-of-function assay to determine the molecular regulatory mechanism of miR-129-5p. Moreover, we detected the expression of nuclear factor kappa B (NF-κB) signaling pathway-related proteins and apoptosis-related factors, and made a serological analysis of the rat serum samples. Results showed that upregulated miR-129-5p or downregulated PEG3 led to reduction of the histological changes of liver cirrhosis and lowered the apoptosis rate, via downstream effects on the NF-κB signaling pathway. Thus, the hepatic fibrosis induced by CCl4 can be rescued by upregulated miR-129-5p or downregulated PEG3 expression.

The Impact of Long Non-Coding RNAs in the Pathogenesis of Hepatocellular Carcinoma

Hepatocellular carcinoma (HCC) is among the utmost deadly human malignancies. This type of cancer has been associated with several environmental, viral, and lifestyle risk factors. Among the epigenetic factors which contribute in the pathogenesis of HCC is dysregulation of long non-coding RNAs (lncRNAs). These transcripts modulate expression of several tumor suppressor genes and oncogenes and alter the activity of cancer-related signaling axes. Several lncRNAs such as NEAT1, MALAT1, ANRIL, and SNHG1 have been up-regulated in HCC samples. On the other hand, a number of so-called tumor suppressor lncRNAs namely CASS2 and MEG3 are down-regulated in HCC. The interaction between lncRNAs and miRNAs regulate expression of a number of mRNA coding genes which are involved in the pathogenesis of HCC. H19/miR-15b/CDC42, H19/miR-326/TWIST1, NEAT1/miR-485/STAT3, MALAT1/miR-124-3p/Slug, MALAT1/miR-195/EGFR, MALAT1/miR-22/SNAI1, and ANRIL/miR-144/PBX3 axes are among functional axes in the pathobiology of HCC. Some genetic polymorphisms within non-coding regions of the genome have been associated with risk of HCC in certain populations. In the current paper, we describe the recent finding about the impact of lncRNAs in HCC.

Silencing of Long Non-coding RNA ENST00000606790.1 Inhibits the Malignant Behaviors of Papillary Thyroid Carcinoma through the PI3K/AKT Pathway

PURPOSE

This study aimed to investigate the role and mechanism of lncRNA ENST00000606790.1 (ENST) in promoting the progression of papillary thyroid carcinoma (PTC).

METHODS

The expression of ENST in human PTC and normal para-cancerous thyroid (NPTC) tissues or cell lines was determined by RT-qPCR. Cell growth was determined by CCK8 assay. Cell colony formation was determined by cell colony formation assay. Cell cycle analysis was performed by staining cells with PI (Propidium Iodide). Cell invasion was assessed by transwell assay. Protein expression was examined by western-blot. siRNA was constructed to inhibit the expression of ENST. 740-Y-P was used to activate PI3K. The correlation between ENST expression and clinical outcomes was analyzed.

RESULTS

ENST was significantly up-regulated in PTC tissues or PTC cell lines (PTC and IHH4 cell lines), compared to NPTC tissues or normal cell lines, respectively. High expression of ENST was strongly correlated to lymph node metastasis and tumor size at diagnosis. Silencing of ENST significantly inhibited cell growth and colony formation, arrested the cell cycle at G2/M phase, upregulated the expression of CHK1, downregulated the expression of CDC25C, and inhibited cell invasion. Silencing of ENST significantly down-regulated the expression of PI3K, p-PI3K, AKT, and p-AKT in IHH4 cells. Furthermore, treatment with the PI3K activator  740-Y-P partially abolished the effect of silencing of ENST on PTC cells.

CONCLUSIONS

Overall, our results demonstrated that ENST can promote PTC progression by activating the PI3K/AKT signaling pathway, suggesting that ENST can serve as a potential biomarker and new therapeutic target for patients with PTC.

Expression of lncRNA MSC-AS1 in hepatocellular carcinoma cell lines and its effect on proliferation, apoptosis, and migration

BACKGROUND/AIMS

This study aimed to explore the expression of long non-coding RNA MSC-AS1 in hepatocellular carcinoma (HCC) cells and its effect on the proliferation, migration, and apoptosis of HCC cells.

MATERIALS AND METHODS

The expression of MSC-AS1 in HCC cell lines BEL7402, SMMC7721, Huh7, HepG2, MHCC97-H, and normal hepatocyte line L02 was detected by reverse transcriptase polymerase chain reaction. The HCC cells were divided into blank, negative control (NC)-small interfering RNA (siRNA) (transfected with negative siRNA), and MSC-AS1 siRNA (transfected with MSC-AS1 siRNA) groups. Cell counting kit-8 and colony formation assays were used to determine the proliferation, and cell apoptosis, migration, and invasion were detected by flow cytometry, wound healing, and transwell assays, respectively. Western blot was used to detect the expression of related proteins.

RESULTS

The expression of MSC-AS1 in HCC cell lines was significantly higher than that in L02. In the MSC-AS1 siRNA group, the proliferation and colony formation of HCC cells were inhibited, whereas the apoptosis rate was significantly higher than that in the blank and NC-siRNA groups. The rate of wound healing and the number of invasion cells in the MSC-AS1 siRNA group were significantly lower than that in the blank and NC-siRNA groups.

CONCLUSION

MSC-AS1 was upregulated in HCC cells, and the downregulation of MSC-AS1 could inhibit cell proliferation, migration, and invasion and promote apoptosis of HCC cells.

Downregulated microRNA-129-5p by Long Non-coding RNA NEAT1 Upregulates PEG3 Expression to Aggravate Non-alcoholic Steatohepatitis

Long non-coding RNAs (lncRNAs) have recently emerged as inflammation-associated biological molecules with a specific role in the progression of liver fibrosis conditions including non-alcoholic steatohepatitis (NASH). The aim of this study was to elucidate the effects of lncRNA nuclear enriched abundant transcript 1 (NEAT1), microRNA-129-5p (miR-129-5p), and paternally expressed gene 3 (PEG3) on the biological activities of hepatic stellate cells (HSCs) subjected to NASH. First, microarray-based analysis revealed upregulated PEG3 in NASH. Liver tissues from mice fed a methionine–choline-deficient (MCD) diet exhibited increased expression of NEAT1 and PEG3 along with lower miR-129-5p expression. A series of in vitro and in vivo assays were then performed on HSCs after transfection with shPEG3, miR-129-5p mimic, or treatment with pyrrolidine dithiocarbamate (PDTC), an inhibitor of the nuclear factor-kappa B (NF-κB) signaling pathway. Results confirmed the alleviated fibrosis by restoring miR-129-5p, while depleting PEG3 or NEAT1, as evidenced by the inactivation of HSCs. To sum up, NEAT1 can bind specifically to miR-129-5p and consequently regulate miR-129-5p and PEG3 expression in relation to the HSC activation occurring in NASH. Thus, NEAT1-targeted inhibition against miR-129-5p presents a promising therapeutic strategy for the treatment of NASH.

Silencing long non-coding RNA NEAT1 attenuates rheumatoid arthritis via the MAPK/ERK signalling pathway by downregulating microRNA-129 and microRNA-204

The participation of long noncoding RNAs (lncRNAs) and microRNAs (miRs) in the progression of rheumatoid arthritis (RA) is a key area of investigation. The current study aimed to investigate the action of lncRNA nuclear paraspeckle assembly transcript 1 (NEAT1) in fibroblast-like synoviocyte (FLS) proliferation and synovitis in RA. A rat model of RA was established. LncRNA NEAT1 expression in the synovial tissues of patients with RA and FLSs from the RA rat model was determined using RT-qPCR. Next, dual luciferase reporter gene assay was applied to investigate the relationship between miR-129/204 and mitogen-activated protein kinase (MAPK)/extracellular regulated protein kinase (ERK). A putative binding relationship between miR-204 and lncRNA NEAT1 was evaluated by RIP assay, and miR-129 promoter methylation was determined using MSP. After the expression of lncRNA NEAT1, miR-129 or miR-204 was altered in FLSs, the extent of ERK1/2 phosphorylation was assessed. In addition, FLS synovitis and proliferation were determined by ELISA and EdU assay, respectively. In RA rats, lncRNA NEAT1 was silenced and miR-129/miR-204 was overexpressed to explore their roles in vivo. LncRNA NEAT1 was upregulated, while miR-129 and miR-204 were downregulated in RA synovial tissues and FLSs. MAPK1 was target gene of both miR-129 and miR-204. LncRNA NEAT1 bound to miR-204 and promoted miR-129 promoter methylation. Silencing lncRNA NEAT1 or overexpressing miR-129/miR-204 enhanced miR-129/miR-204 expression, but reduced the extent of ERK1/2 phosphorylation, proliferation of FLSs, and synovitis in RA. Collectively, silencing lncRNA NEAT1 promoted miR-129 and miR-204 to inhibit the MAPK/ERK signalling pathway, reducing FLS synovitis in RA.Abbreviations: ACR: American College of Rheumatology; ELISA: Enzyme-linked immunosorbent assay; ERK: extracellular signal-regulated kinase; FLS: fibroblast-like synoviocyte; GADPH: glyceraldehyde-3-phosphate dehydrogenase; HRP: horseradish peroxidase; IFA: Incomplete Freund's Adjuvant; lncRNAs: long noncoding RNAs; MSP: Methylation-specific PCR; NC: negative control; NEAT1: nuclear paraspeckle assembly transcript 1; OD: optical density; RA: rheumatoid arthritis; RIPA: Radio Immunoprecipitation Assay; RLU: relative light units; RT-qPCR: reverse transcription quantitative polymerase chain reaction; UTR: untranslated region.

Hepigenetics: A Review of Epigenetic Modulators and Potential Therapies in Hepatocellular Carcinoma

Hepatocellular carcinoma is the fifth most common cancer worldwide and the second most lethal, following lung cancer. Currently applied therapeutic practices rely on surgical resection, chemotherapy and radiotherapy, or a combination thereof. These treatment options are associated with extreme adversities, and risk/benefit ratios do not always work in patients' favor. Anomalies of the epigenome lie at the epicenter of aberrant molecular mechanisms by which the disease develops and progresses. Modulation of these anomalous events poses a promising prospect for alternative treatment options, with an abundance of felicitous results reported in recent years. Herein, the most recent epigenetic modulators in hepatocellular carcinoma are recapitulated on.

LncRNA NEAT1/microRNA-129-5p/SOCS2 axis regulates liver fibrosis in alcoholic steatohepatitis

Background

Long non-coding RNA nuclear paraspeckle assembly transcript 1 (NEAT1) has been reported to play an essential role in non-alcoholic fatty liver disease. However, the role of NEAT1 in regulation of alcoholic steatohepatitis (ASH) remains largely unknown. This study aims to explore the role of NEAT1 in ASH by mediating microRNA-129-5p (miR-129-5p) targeting suppressor of cytokine signaling 2 (SOCS2).

Methods

NEAT1, miR-129-5p and SOCS2 expression in serum of ASH patients were assessed. In the in vitro cellular experiment, we transfected siRNAs, oligonucleotides or plasmids into ethanol-induced AML-12 mouse hepatocytes to alter NEAT1 and miR-129-5p expression, and inflammatory factors and lipid content were determined. In the in vivo animal experiment, we injected lentiviruses carrying siRNAs, oligonucleotides or plasmids onto ASH mice (ASH induced by feeding mice a Lieber-DeCarli ethanol diet) to alter NEAT1 and miR-129-5p expression through the tail vein. Serum liver function, blood lipids and inflammatory factors were detected; liver histopathology, liver cell apoptosis, and fibrosis were observed. The relationship between NEAT1 and miR-129-5p, or between miR-129-5p and SOCS2 was verified.

Results

MiR-129-5p was reduced while NEAT1 and SOCS2 were elevated in ASH. Inhibited NEAT1 or elevated miR-129-5p suppressed the elevated lipid metabolism and restrained inflammation reaction in ethanol-stimulated AML-12 cells. The promoted miR-129-5p and inhibited NEAT1 could improve the liver function and repress blood lipid, inflammation reaction, hepatocyte apoptosis and liver fibrosis in ethanol-induced ASH mice. Furthermore, NEAT1 could negatively regulate miR-129-5p to target SOCS2.

Conclusion

We have found that the inhibited NEAT1 could suppress liver fibrosis in ASH mice by promoting miR-129-5p and restraining SOCS2, thereby decelerating the development of ASH.

LncRNA NEAT1: Shedding light on mechanisms and opportunities in liver diseases

With advances in genome and transcriptome research technology, the function and mechanism of lncRNAs in physiological and pathological states have been gradually revealed. Nuclear Enriched Abundant Transcript 1 (NEAT1, a long non-coding RNA), a vital component of paraspeckles, plays an indispensable role in the formation and integrity of paraspeckles. Throughout the research history, NEAT1 is mostly aberrantly upregulated in various cancers, and high expression of NEAT1 often contributes to poor prognosis of patients. Notably, the role and mechanism of NEAT1 in liver diseases have been increasingly reported. NEAT1 accelerates the progression of non-alcoholic fatty liver disease (NAFLD), liver fibrosis and hepatocellular carcinoma, while exerting a protective role in the pathogenesis of acute-on-chronic liver failure by inhibiting the inflammatory response. In this review, we will elaborate on relevant studies on the different casting of NEAT1 in liver diseases, especially focusing on its regulatory mechanisms and new opportunities for alcoholic liver disease.

NEAT1 and Paraspeckles in Cancer Development and Chemoresistance

Non-coding RNA were previously thought to be biologically useless molecules arising from simple transcriptional noise. These are now known to be an integral part of cellular biology and pathology. The wide range of RNA molecules have a diverse range of structures, functions, and mechanisms of action. However, structural long non-coding RNAs (lncRNAs) are a particular class of ncRNA that are proving themselves more and more important in cellular biology, as the exact structures that such RNAs form and stabilise become more understood. Nuclear Enriched Abundant Transcript 1 (NEAT1) is a specific structural RNA emerging as a critical component in the progress and development of cancer. NEAT1 forms part of multiple biological pathways, acting through a diverse group of mechanisms. The most important of these is the formation of the paraspeckle, through which it can influence the stability of a tumour to develop resistance to drugs. This review will thus cover the range of effects by which NEAT1 interacts with cancer progression in order to describe the various roles of NEAT1 in chemoresistance, as well as to identify drug targets that protein research alone could not provide.

LncRNA ANRIL promotes cell growth, migration and invasion of hepatocellular carcinoma cells via sponging miR-144

Antisense non-coding RNA in the INK4A locus (ANRIL) has been recognized as a cancer-related lncRNA in hepatocellular carcinoma previously. This study aimed to reveal the functional effects and mechanisms of ANRIL on hepatocellular carcinoma cells in vitro. The expression of ANRIL in hepatocellular carcinoma cell lines (MHCC97 and Li-7) and non-tumourigenic liver cell line THLE-3 was detected by qRT-PCR. The expression of ANRIL, miR-144 and PBX3 in hepatocellular carcinoma cells was altered simultaneously or respectively by vector/oligonucleotide transfection. Then, cell viability, migration, invasion, apoptotic cell rate, protein expression of apoptosis-related factors were assessed. The correlation between ANRIL, miR-144 and PBX3 was explored. ANRIL was highly expressed in MHCC97 and Li-7 cells when compared to THLE-3 cells. ANRIL overexpression promoted cell viability, migration, invasion and suppressed apoptosis of MHCC97 and Li-7 cells. ANRIL negatively regulated miR-144, and oncogenic effects of ANRIL were attenuated when miR-144 was overexpressed. PBX3 was a direct target of miR-144. miR-144 overexpression blocked PI3K/AKT and JAK/STAT signalling pathways via targeting PBX3. Our data documented that ANRIL promoted hepatocellular carcinoma cells growth, migration and invasion. One of the possible mechanisms responsible for the tumour-promoting actions is that ANRIL sponging miR-144 to derepress PBX3.

Our emerging understanding of the roles of long non-coding RNAs in normal liver function, disease, and malignancy

Long non-coding RNAs (lncRNAs) are important biological mediators that regulate numerous cellular processes. New experimental evidence suggests that lncRNAs play essential roles in liver development, normal liver physiology, fibrosis, and malignancy, including hepatocellular carcinoma and cholangiocarcinoma. In this review, we summarise our current understanding of the function of lncRNAs in the liver in both health and disease, as well as discuss approaches that could be used to target these non-coding transcripts for therapeutic purposes.

Long Noncoding RNA NEAT1 Promotes Myocardiocyte Apoptosis and Suppresses Proliferation Through Regulation of miR-129-5p

Recent studies have revealed the important role of long noncoding RNAs (lncRNAs) in heart development and pathogenesis. This study was aimed to investigate the role of NEAT1 in hypoxia-induced cardiac injury and explore its possible molecular mechanism. Real-time PCR (RT-PCR) was used to determine the relative RNA expression of NEAT1 and its potential target microRNA, miR-129-5p, in the plasma of patients with acute myocardial infarction, heart failure, and angina, as well as in H2O2-treated H9c2 cells. The role of NEAT1 overexpression or inhibition in H9c2 cell migration and proliferation was assessed by transwell assay and Edu staining, respectively. Collagen deposition and apoptosis were evaluated by Western blot detection of collagen and apoptotic proteins, including Capase3, Bax, and Bcl2. We showed that H2O2 treatment significantly decreased H9c2 cell migration and proliferation while increasing H9c2 cell apoptosis. Inhibition of NEAT1 attenuated the cell apoptosis and alleviated proliferation inhibition induced by hypoxia. Bioinformatics analysis showed that miR-129-5p was the direct target of NEAT1, which was confirmed by luciferase assay. NEAT1 upregulation aggravated apoptosis by downregulating miR-129-5p. In conclusion, we uncovered a novel NEAT1-miR-129 axis and its implication in H2O2-induced heart failure.

LncRNA NEAT1/miR-129/Bcl-2 signaling axis contributes to HDAC inhibitor tolerance in nasopharyngeal cancer

Histone deacetylase inhibitors (HDACis) - based therapeutic drug tolerance is one of the principal factors of poor prognosis of patients with nasopharyngeal cancer (NPC). Mechanisms of tolerance to HDACis are not well understood. Nowadays, dysregulation of long non-coding RNAs (LncRNAs) and microRNAs (miRNAs) has been reported to provide beneficial or inhibitory effects in drug-tolerance in various cancers. Herein, we established the HDAC inhibitor (SAHA)-tolerant NPC cell sublines, which had decreased apoptosis in response to SAHA treatment. We observed that the expression of miR-129 was significantly reduced in SAHA-tolerant NPC cells. Manipulating the expression of miR-129 overcame SAHA tolerance, and enhanced the SAHA-induced apoptosis. In terms of miR-129 downregulation, we identified that NEAT1 suppresses miR-129 expression. NEAT1 was found to be upregulated in SAHA tolerance cells. The depletion of NEAT1 phenocopied the effect of miR-129 overexpression, which also enhanced SAHA-induced apoptosis. Bcl-2 was the downstream target of miR-129 and contributed to SAHA tolerance in NPC. Our in vivo xenograft experiment confirmed that the administration of miR-129 or inhibition of Bcl-2 overcame the SAHA tolerance in NPC. In conclusion, NEAT1 increases in NPC tissues and manages to facilitate SAHA tolerance by modulating the miR-129/Bcl-2 axis, providing novel therapeutic targets for NPC treatment.

Serum expression and diagnostic potential of long non-coding RNAs NEAT1 and TUG1 in viral hepatitis C and viral hepatitis C-associated hepatocellular carcinoma

BACKGROUND

The present study investigated the serum detectability and the diagnostic implications of long non-coding RNAs; nuclear enriched abundant transcript 1 (NEAT1) and taurine upregulated gene 1 (TUG1) in viral hepatitis C (HCV) and HCV-associated hepatocellular carcinoma (HCC).

METHODS

The study included twenty healthy controls, forty non-malignant HCV patients and forty HCV-associated HCC patients. The study assessed liver function tests, the antioxidant status, serum alpha fetoprotein, p53, NEAT1 and TUG1.

RESULTS

Diminished serum expression of NEAT1 and TUG1 was observed in HCV and HCV-associated HCC and was closely associated with deregulated liver function and elevated AFP levels. A model of NEAT1, TUG1 and AFP accurately differentiated between HCC patients and healthy controls with sensitivity greater than that of AFP alone. Additionally, the diagnostic performance of a model of TUG1, p53 and AFP was superior to that of each marker alone for predicting HCC in HCV patients.

CONCLUSION

Significant alterations in the serum expression of NEAT1 and TUG1 in HCV and HCV-associated HCC patients were recorded. We propose NEAT1 and TUG1 as non-invasive, cost-effective and complementary biomarkers that improve the diagnostic characteristics of AFP.

MiR-22 as a metabolic silencer and liver tumor suppressor

With obesity rate consistently increasing, a strong relationship between obesity and fatty liver disease has been discovered. More than 90% of bariatric surgery patients also have non-alcoholic fatty liver diseases (NAFLDs). NAFLD and non-alcoholic steatohepatitis (NASH), which are the hepatic manifestations of metabolic syndrome, can lead to liver carcinogenesis. Unfortunately, there is no effective medicine that can be used to treat NASH or liver cancer. Thus, it is critically important to understand the mechanism underlying the development of these diseases. Extensive evidence suggests that microRNA 22 (miR-22) can be a diagnostic marker for liver diseases as well as a treatment target. This review paper focuses on the roles of miR-22 in metabolism, steatosis, and liver carcinogenesis. Literature search is limited based on the publications included in the PubMed database in the recent 10 years.

NEAT1 is Required for the Expression of the Liver Cancer Stem Cell Marker CD44

CD44, a cancer stem cell (CSC) marker, is required for maintaining CSC properties in hepatocellular carcinoma (HCC). Nuclear enriched abundant transcript 1 (NEAT1), a long noncoding RNA (lncRNA), is an oncogenic driver in HCC. In the present study, we investigated the significance of the NEAT1 gene in association with CD44 expression in liver CSCs of human HCC cell lines. The CSC properties were evaluated by spheroid culture, CSC marker expression, and sensitivity to anti-cancer drugs. The expression of both NEAT1 variant 1 (NEAT1v1) and variant 2 (NEAT1v2) as well as CD44 was significantly increased in the spheroid culture, compared with that in monolayer culture. Overexpression of Neat1v1, but not Neat1v2, enhanced the CSC properties, while knockout of the NEAT1 gene suppressed them. CD44 expression was increased by the overexpression of Neat1v1 and abrogated by NEAT1 knockout. The overexpression of NEAT1v1 restored the CSC properties and CD44 expression in NEAT1-knockout cells. NEAT1v1 expression in HCC tissues was correlated with poor prognosis and CD44 expression. These results suggest that NEAT1v1 is required for CD44 expression. To our surprise, NEAT1v1 also restored the CSC properties even in CD44-deficient cells, suggesting that NEAT1v1 maintains the properties of CSCs in a CD44-independent manner.

Integrative analysis of an lncRNA‑associated competing endogenous RNA network in human trabecular meshwork cells under oxidative stress

Long non‑coding RNAs (lncRNAs) are a group of non‑coding transcripts of >200 nucleotides. They can act as competing endogenous RNAs (ceRNAs) and suppress microRNA (miRNA) function by preventing them from binding to and interacting with target mRNAs. However, the specific role of the lncRNA‑associated ceRNA network in the pathogenesis of glaucoma has not yet been elucidated. To study this, data were downloaded from the Gene Expression Omnibus database (GSE126170), which contained three human trabecular meshwork cell (HTMC) samples treated with 300 µm hydrogen peroxide and three control samples treated with vehicle. Differentially expressed lncRNAs and mRNAs of HTMCs were obtained using the R package limma. Gene Ontology and Kyoto Encyclopedia of Genes and Genomes pathway analyses of differentially expressed mRNAs were performed using the R package clusterProfiler. Finally, the ceRNA network was constructed using the mircode, miRDB, miRTarBase and TargetScan databases, and visualized using Cytoscape v3.6.1. The results showed that 70 lncRNAs and 558 mRNAs were identified to be significantly dysregulated (|log2FoldChange| >1 and adjusted P<0.05) in HTMCs under oxidative stress compared to those in HTMCs under control conditions. Moreover, 24 lncRNAs, 24 miRNAs and 40 mRNAs were closely connected, and were part of the ceRNA network. Among these, the expression levels of 19 lncRNAs were upregulated, and those of 5 lncRNAs were downregulated. To conclude, using bioinformatics analysis, the differential expression profiles of lncRNAs were reported and a lncRNA‑associated ceRNA network in HTMCs under oxidative stress was constructed. These results may bring to light a new pathological mechanism or a potential therapeutic target for glaucoma.

BCLAF1 promotes cell proliferation, invasion and drug-resistance though targeting lncRNA NEAT1 in hepatocellular carcinoma

AIMS

In the present research, we aimed to investigate the effect of Bcl-2-associated transcription factor 1 (BCLAF1) on hepatocellular carcinoma and further explore the special molecular mechanism.

MAIN METHODS

The expression of BCLAF1 was analyzed in tumor tissues and different hepatocellular cancer cell lines by real-time RT-PCR and Western blot. Cell proliferation and invasion was explored using MTT and Transwell assay respectively. In addition, luciferase reporter assay was performed to determine the binding activity of BCLAF1 and Nuclear enrichment-rich transcription factor 1 (NEAT1) promoter. Finally, the IC50 for 5-Fluorouracil (5-Fu) was measured by MTT assay, and Western blot was used to determine the expression of P-glycoprotein (P-gp) and multidrug resistance protein1 (MRP1).

KEY FINDING

The result revealed that BCLAF1 was highly expressed in hepatocellular carcinoma tissues and cells. In addition, BCLAF1-siRNA inhibited the proliferation and invasion of hepatocellular carcinoma cells, and overexpression of BCLAF1 promoted proliferation and invasion. Furthermore, luciferase reporter assay demonstrated that BCLAF1 directly interact with lncNEAT1 promoter and improved NEAT1 expression, and BCLAF1 promoted proliferation and invasion through targeting lncRNA NEAT1. What's more, BCLAF1 promoted 5-Fu resistance and the expression of P-gp and MRP1 in hepatocellular carcinoma cells by targeting NEAT1.

SIGNIFICANCE

The results of the present study suggested that BCLAF1 might be a new gene related to proliferation and drug-resistance of hepatocellular carcinoma. In the future, the search for a deep and reasonable mechanism for the role of BCLAF1 will help us to understand its function more comprehensively, and finally find a new method for the treatment of human cancer.

Long non-coding RNA NEAT1 promotes bladder progression through regulating miR-410 mediated HMGB1

LncRNA NEAT1 is reported as a crucial oncogene in multiple cancers. But, its biological role in bladder cancer is barely understood. Therefore, we concentrated on the function and role of NEAT1 in bladder cancer. Firstly, NEAT1 expression in bladder cancer cells was determined and it was displayed NEAT1 was significant elevated. NEAT1 was knockdown and overexpressed in T24 and J82 cells. Then it was indicated that NEAT1 silence greatly inhibited bladder cancer cell proliferation with an increased ratio of apoptotic cells and severe cell cycle arrest. Overexpression of NEAT1 exhibited a reversed process in bladder cancer cells. Additionally, in vivo experiments were employed using establishment of nude mice models. NEAT1 knockdown inhibited bladder cancer growth while increase of NEAT1 promoted bladder cancer development in vivo. By employing the bioinformatics analysis, we speculated that miR-410 was as a downstream target of NEAT1. Then, the targeting association between them was proved in our research and we implicated miR-410 was dramatically restrained in bladder cancer cells. Meanwhile, it was exhibited that miR-410 was negatively regulated by NEAT1. Apart from these, HMGB1 was speculated as a downstream target of miR-410. Dual-luciferase reporter assay was used to prove the correlation between miR-410 and HMGB1. Up-regulation of miR-410 restrained HMGB1 levels and NEAT1 can regulate HMGB1 level via sponging miR-410. To sum up, we implied NEAT1/miR-410/HMGB1 axis participated in bladder cancer.

Long non-coding RNA NONHSAT101069 promotes epirubicin resistance, migration, and invasion of breast cancer cells through NONHSAT101069/miR-129-5p/Twist1 axis

Drug resistance, including epirubicin-based therapeutic resistance, is one of the major reasons responsible for the unfavorable prognosis of patients diagnosed with breast cancer (BC). Acquired chemoresistance and metastatic properties have been identified to be closely associated with the process of epithelial-mesenchymal transition (EMT). Recently, dysregulation of long non-coding RNAs (lncRNAs) have been increasingly reported to perform promotive or suppressive functions in chemoresistance and EMT process in multiple cancers. However, relevant novel lncRNA participating in epirubicin resistance and EMT and its underlying molecular mechanisms remain unknown in BC. Herein, we established the epirubicin-resistant breast cancer cell subline (MCF-7/ADR), which presented mesenchymal phenotype and increased metastatic potential. A panel of differentially expressed lncRNAs, including 268 upregulated and 49 downregulated lncRNAs, were identified by high-flux microarray investigation in MCF-7 and MCF-7/ADR cells. The novel lncRNA NONHSAT101069 was significantly overexpressed in BC specimens, BC cell lines, and epirubicin-resistant cell sublines. The knockdown of NONHSAT101069 significantly repressed, whereas overexpression of NONHSAT101069 promoted the epirubicin resistance, migration, invasion and EMT process of BC cells both in vitro and in vivo. Further mechanism-related researches uncovered that NONHSAT101069 functioned as a ceRNA (competing endogenous RNA) via sponging miR-129-5p. Twist1 was a direct downstream protein of NONHSAT101069/miR-129-5p axis in BC cells. To conclude, NONHSAT101069 was upregulated in BC tissues and promoted epirubicin resistance, migration and invasion of BC cells via regulation of NONHSAT101069/miR-129-5p/Twist1 axis, highlighting its potential as an oncogene and a therapeutic biomarker for BC.

Long noncoding RNA NEAT1 suppresses sorafenib sensitivity of hepatocellular carcinoma cells via regulating miR-335-c-Met

OBJECTIVES

To investigate the role of long noncoding RNA (lncRNA) nuclear-enriched abundant transcript 1 (NEAT1) in regulating sorafenib (Sora) sensitivity of hepatocellular carcinoma (HCC) cells and possible signaling pathways.

METHODS

HCC cell lines and tumor tissue were quantified for NEAT1 expression by quantitative polymerase chain reaction (qPCR). Following shRNA (short hairpin RNA) knockdown of NEAT1, cell viability, apoptosis, and related protein expression were measured after drug treatment. The downstream target of NEAT1, including miR-335 and c-Met was studied using a combination of luciferase binding assay, gene knockdown/overexpression, western blot analysis, and cell viability/apoptosis assay. Cancer cells with NEAT1 knockdown were transplanted onto nude mice for in vivo tumorigenesis assay.

RESULTS

Silencing of NEAT1 in HCC cells facilitated Sora sensitivity by enhancing drug-induced apoptosis, and led to smaller tumor size on nude mice. Mechanistic study suggested that miR-335 was negatively regulated by NEAT1, and miR-335 further suppressed c-Met-Akt pathway, whose activation caused drug resistance of HCC cells. The knockdown of miR-335, or overexpression of c-Met, all remarkably abolished the proapoptotic effect of NEAT1 knockdown in HCC cells.

CONCLUSION

lncRNA NEAT1 mediates Sora resistance of HCC cells by suppressing miR-335 expression, and disinhibition on c-Met-Akt signaling pathway. Our results provide potency of NEAT1 as the biomarker for drug resistant HCC and possible treating targets.

NEAT1/miR‑124/STAT3 feedback loop promotes breast cancer progression

The long non‑coding RNA nuclear enriched abundant transcript 1 (NEAT1) has important roles in the regulation of multiple cell functions, such as proliferation, apoptosis and migration. However, the mechanism by which NEAT1 regulates breast cancer progression is not well elucidated. In the present study, NEAT1 and microRNA‑124 (miR‑124) levels were detected by reverse transcription‑quantitative PCR in breast cancer tissues and cell lines. STAT3 protein levels were detected by western blot analysis. Cell proliferation and cell cycle distribution were determined using MTT and colony formation assays, and flow cytometry, respectively. The results demonstrated that NEAT1 and STAT3 expression levels were increased in breast cancer tissues compared with normal breast tissues, whereas miR‑124 expression was significantly decreased. Functional analyses revealed that NEAT1 promoted cell proliferation and cell cycle progression in breast cancer cells. Additionally, NEAT1 and STAT3 expression levels were negatively correlated with miR‑124 levels in breast cancer tissues. A direct interaction between miR‑124, and NEAT1 and STAT3, was predicted by bioinformatics analysis and confirmed using a luciferase activity assay. NEAT1 overexpression markedly increased STAT3 protein expression levels, and this effect was reversed by miR‑124 overexpression in breast cancer cells. Furthermore, miR‑124 overexpression partially attenuated the effects of NEAT1 on breast cancer cell proliferation and cell cycle progression. The inhibitory effects of miR‑124 overexpression on the proliferation rate and cell cycle progression were abolished by STAT3 overexpression. In turn, STAT3 silencing inhibited NEAT1 transcription in breast cancer cells. In summary, the present findings revealed that NEAT1 and STAT3 formed a feedback loop via sponging miR‑124 to promote breast cancer progression.

Evaluation of serum long noncoding RNA NEAT and MiR-129-5p in hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is one of the most prevalent form of cancer. Various long non coding RNA (lncRNAs) and micro RNA have been confirmed to have a role in the progression of HCC. Our aim was to investigate for the first time the expression profile of serum level of LNC NEAT (nuclear enrich abundant transcript) and MiR-129-5p in HCC patients and their relations with patient's clinical and biochemical investigations rather than previous studies on tissue cell lines. Our study includes 72 subjects divided into 36 as control subjects and 36 patients with HCC. Complete physical and laboratory investigations were done on all subjects. RNAs were extracted from sera of all subjects. RNAs were reversed transcribed into cDNAs using Qiagen, Valenica, CA. Quantitative PCR (qPCR) was performed using Rotor gene Q System (Qiagen). Relative NEAT1 expression level was significantly increased in serum of HCC patients 4.7 (1.31-6.82) (p < .0001). Meanwhile MiR-129-5p relative expression level was significantly decreased in serum of HCC patients 0.17 (0.14-20) (p < .0001). Also there was negative significant correlation between the expression level of LNC NEAT and MiR-129-5p in HCC group (p < .0001). ROC curve analysis revealed that LNC NEAT; AUC = 0.981, p < .0001, cutoff value (1.02), sensitivity 100%, specificity 88.9%. MiR-129-5p; AUC = 0.997, p < .0001, cutoff value (0.43), sensitivity 100%, specificity 97.2%. Serum LNC NEAT and MiR-129-5p could be used as potential biomarkers for HCC cancer diagnosis and prognosis.