Knockdown long non-coding RNA ANRIL inhibits proliferation, migration and invasion of HepG2 cells by down-regulation of miR-191

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.

The Long Non-Coding RNA ANRIL in Cancers

ANRIL (Antisense Noncoding RNA in the INK4 Locus), a long non-coding RNA encoded in the human chromosome 9p21 region, is a critical factor for regulating gene expression by interacting with multiple proteins and miRNAs. It has been found to play important roles in various cellular processes, including cell cycle control and proliferation. Dysregulation of ANRIL has been associated with several diseases like cancers and cardiovascular diseases, for instance. Understanding the oncogenic role of ANRIL and its potential as a diagnostic and prognostic biomarker in cancer is crucial. This review provides insights into the regulatory mechanisms and oncogenic significance of the 9p21 locus and ANRIL in cancer.

Making Sense of Antisense lncRNAs in Hepatocellular Carcinoma

Transcriptome complexity is emerging as an unprecedented and fascinating domain, especially by high-throughput sequencing technologies that have unveiled a plethora of new non-coding RNA biotypes. This review covers antisense long non-coding RNAs, i.e., lncRNAs transcribed from the opposite strand of other known genes, and their role in hepatocellular carcinoma (HCC). Several sense-antisense transcript pairs have been recently annotated, especially from mammalian genomes, and an understanding of their evolutionary sense and functional role for human health and diseases is only beginning. Antisense lncRNAs dysregulation is significantly involved in hepatocarcinogenesis, where they can act as oncogenes or oncosuppressors, thus playing a key role in tumor onset, progression, and chemoradiotherapy response, as deduced from many studies discussed here. Mechanistically, antisense lncRNAs regulate gene expression by exploiting various molecular mechanisms shared with other ncRNA molecules, and exploit special mechanisms on their corresponding sense gene due to sequence complementarity, thus exerting epigenetic, transcriptional, post-transcriptional, and translational controls. The next challenges will be piecing together the complex RNA regulatory networks driven by antisense lncRNAs and, ultimately, assigning them a function in physiological and pathological contexts, in addition to defining prospective novel therapeutic targets and innovative diagnostic tools.

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.

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.

Roles of lncRNAs Mediating Wnt/β-Catenin Signaling in HCC

Hepatocellular carcinoma (HCC) is considered the second most deadly cancer worldwide. Due to the absence of early diagnostic markers and effective therapeutic approaches, distant metastasis and increasing recurrence rates are major difficulties in the clinical treatment of HCC. Further understanding of its pathogenesis has become an urgent goal in HCC research. Recently, abnormal expression of long noncoding RNAs (lncRNAs) was identified as a vital regulator involved in the initiation and development of HCC. Activation of the Wnt/β-catenin pathway has been reported to obviously impact cell proliferation, invasion, and migration of HCC. This article reviews specific interactions, significant mechanisms and molecules related to HCC initiation and progression to provide promising strategies for treatment.

Long Noncoding Competing Endogenous RNA Networks in Pancreatic Cancer

Pancreatic cancer (PC) is a highly malignant disease characterized by insidious onset, rapid progress, and poor therapeutic effects. The molecular mechanisms associated with PC initiation and progression are largely insufficient, hampering the exploitation of novel diagnostic biomarkers and development of efficient therapeutic strategies. Emerging evidence recently reveals that noncoding RNAs (ncRNAs), including long ncRNAs (lncRNAs) and microRNAs (miRNAs), extensively participate in PC pathogenesis. Specifically, lncRNAs can function as competing endogenous RNAs (ceRNAs), competitively sequestering miRNAs, therefore modulating the expression levels of their downstream target genes. Such complex lncRNA/miRNA/mRNA networks, namely, ceRNA networks, play crucial roles in the biological processes of PC by regulating cell growth and survival, epithelial-mesenchymal transition and metastasis, cancer stem cell maintenance, metabolism, autophagy, chemoresistance, and angiogenesis. In this review, the emerging knowledge on the lncRNA-associated ceRNA networks involved in PC initiation and progression will be summarized, and the potentials of the competitive crosstalk as diagnostic, prognostic, and therapeutic targets will be comprehensively discussed.

Long Non-Coding RNA ANRIL as a Potential Biomarker of Chemosensitivity and Clinical Outcomes in Osteosarcoma

Osteosarcoma has a poor prognosis due to chemo-resistance and/or metastases. Increasing evidence shows that long non-coding RNAs (lncRNAs) can play an important role in drug sensitivity and cancer metastasis. Using osteosarcoma cell lines, we identified a positive correlation between the expression of a lncRNA and ANRIL, and resistance to two of the three standard-of-care agents for treating osteosarcoma-cisplatin and doxorubicin. To confirm the potential role of ANRIL in chemosensitivity, we independently inhibited and over-expressed ANRIL in osteosarcoma cell lines followed by treatment with either cisplatin or doxorubicin. Knocking-down ANRIL in SAOS2 resulted in a significant increase in cellular sensitivity to both cisplatin and doxorubicin, while the over-expression of ANRIL in both HOS and U2OS cells led to an increased resistance to both agents. To investigate the clinical significance of ANRIL in osteosarcoma, we assessed ANRIL expression in relation to clinical phenotypes using the osteosarcoma data from the Therapeutically Applicable Research to Generate Effective Treatments (TARGET) dataset. Higher ANRIL expression was significantly associated with increased rates of metastases at diagnosis and death and was a significant predictor of reduced overall survival rate. Collectively, our results suggest that the lncRNA ANRIL can be a chemosensitivity and prognosis biomarker in osteosarcoma. Furthermore, reducing ANRIL expression may be a therapeutic strategy to overcome current standard-of-care treatment resistance.

Differential non-coding RNAs expression profiles of invasive and non-invasive pituitary adenomas

Background

Pituitary adenoma (PA) accounts for 10–15% of all intracranial neoplasms. Despite their benign nature, PA often shows invasive growth. MicroRNAs (miRNAs) and long non-coding RNAs (lncRNAs) are a class of non-coding RNAs that play important roles in PA initiation and progression.

Aim

The aim of this study was to find specific profiles of miR-200a and long non-coding RNA (lncRNA) antisense non-coding RNA in the INK4 locus (ANRIL) in PA based on a comparative study using Real-time quantitative reverse transcription polymerase chain reaction (qRT-PCR) analyses of tumor tissue and plasma.

Methods

Plasma and PA tissue samples were obtained from two groups of included patients (15 invasive and 15 non-invasive PA). In addition, plasma samples from patients with invasive PA have collected pre- and post-operation. Plasma and tissue samples subjected to qRT-PCR analyses for the expression levels of miR-200a and lncRNA ANRIL.

Results

The expression levels of miR-200a and lncRNA ANRIL were increased in tissue samples patients with invasive PA than in the patients with non-invasive PA. In addition, the expression levels of circulating miR-200a and lncRNA ANRIL were increased in patients with invasive PA than in patients with non-invasive PA in the pre-operation period. However, the expression level of plasma circulating miR-200a and lncRNA ANRIL was decreased in patients with invasive PA in the post-operation period. Our results depicted a miR-200a and lncRNA ANRIL expression in tissue and plasma samples in the patients with invasive PA. In addition, Receiver Operating Characteristic (ROC) curve was used to evaluate the diagnostic value of these circulating miR-200a and lncRNA ANRIL.

Conclusion

The expression of these tumor-associated ncRNAs has been elevated in the PAs. Therefore, miR-200a and lncRNA ANRIL represents as biomarkers for diagnosis and potential targets for novel invasive PA treatment strategies.

The role of lncRNA ANRIL in the progression of hepatocellular carcinoma

OBJECTIVES

The aim of the current study was to identify the long noncoding RNAs (lncRNAs) ANRIL function and molecular pathways underlying hepatocellular carcinoma progression.

METHODS

ANRIL knockdown with specific siRNA, and transfected into HepG2 cells according to the protocol of Lipofectamine 2000. Cell proliferation, apoptosis, migration and metastasis were assessed with MTT assay, flow cytometry and wound healing assay, respectively. Moreover, the expression level of ANRIL, apoptosis-related genes, and the Wnt pathway-associated genes were assessed by real time-PCR and Western blot assay.

KEY FINDINGS

Knocking down of ANRIL led to alleviated cell growth and increased cell apoptosis of HepG2 cells through markedly increased expression levels of Bax and Bad. In contrast, dramatically diminished the expressions of anti-apoptotic factors including Bid and Bcl-2 in comparison to the scrambled control group (si-NC). Furthermore, ANRIL silencing resulted in an inactivated Wnt/β-catenin pathway by suppressing key genes associated with this pathway.

CONCLUSIONS

Taken together, these findings imply new insights into the regulatory network of the Wnt pathway through lncRNA ANRIL that indicate ANRIL may be a therapeutic factor potential for hepatocellular carcinoma.

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.

Down-regulation of long non-coding RNA antisense non-coding RNA in the INK4 locus suppresses OVCAR-3 cells proliferation and induction of apoptosis by Wnt/β -catenin

OBJECTIVES

Ovarian cancer is a lethal gynecological malignancy. Long non-coding RNA antisense non-coding RNA in the INK4 locus (lncRNA ANRIL) was reported to have a critical role in cancer advancement. The ANRIL-mediated oncogenic underlying molecular mechanisms are not fully understood in ovarian cancer. We aimed to study ANRIL silencing effects on the proliferation and apoptosis of OVCAR-3 cells.

METHODS

The ANRIL was Knockdown by transfection of OVCAR-3 cells with si-RNA against ANRIL. MTT assay and cell death ELISA kit were used to evaluate cellular proliferation and apoptosis. The expression levels of ANRIL, pro-and anti-apoptotic genes were assessed using q-RT-PCR. Western blotting was used to assess Wnt/β-catenin signalling pathway.

KEY FINDINGS

ANRIL down-regulating in OVCAR-3 cell lines resulted in significant inhibition of cellular proliferation, apoptosis induction, as well as suppression of cellular invasion. Besides, knockdown of ANRIL led to pro-apoptotic genes up-regulation, Bad and Bax and anti-apoptotic genes down-regulation, Bid and Bcl-2. More importantly, we observed that ANRIL inhibition suppressed the vital components expression of the Wnt/β-catenin cascade.

CONCLUSION

Our findings showed that down-regulation of lncRNA ANRIL resulted in the effective suppression of OVCAR-3 cell proliferation and invasion and induction of apoptosis by preventing Wnt/β-catenin signal transduction.

Identification of miRNA-Mediated Subpathways as Prostate Cancer Biomarkers Based on Topological Inference in a Machine Learning Process Using Integrated Gene and miRNA Expression Data

Accurately identifying classification biomarkers for distinguishing between normal and cancer samples is challenging. Additionally, the reproducibility of single-molecule biomarkers is limited by the existence of heterogeneous patient subgroups and differences in the sequencing techniques used to collect patient data. In this study, we developed a method to identify robust biomarkers (i.e., miRNA-mediated subpathways) associated with prostate cancer based on normal prostate samples and cancer samples from a dataset from The Cancer Genome Atlas (TCGA; n = 546) and datasets from the Gene Expression Omnibus (GEO) database (n = 139 and n = 90, with the latter being a cell line dataset). We also obtained 10 other cancer datasets to evaluate the performance of the method. We propose a multi-omics data integration strategy for identifying classification biomarkers using a machine learning method that involves reassigning topological weights to the genes using a directed random walk (DRW)-based method. A global directed pathway network (GDPN) was constructed based on the significantly differentially expressed target genes of the significantly differentially expressed miRNAs, which allowed us to identify the robust biomarkers in the form of miRNA-mediated subpathways (miRNAs). The activity value of each miRNA-mediated subpathway was calculated by integrating multiple types of data, which included the expression of the miRNA and the miRNAs’ target genes and GDPN topological information. Finally, we identified the high-frequency miRNA-mediated subpathways involved in prostate cancer using a support vector machine (SVM) model. The results demonstrated that we obtained robust biomarkers of prostate cancer, which could classify prostate cancer and normal samples. Our method outperformed seven other methods, and many of the identified biomarkers were associated with known clinical treatments.

Knockdown of long non‑coding RNA ANRIL inhibits the proliferation and promotes the apoptosis of Burkitt lymphoma cells through the TGF‑β1 signaling pathway

Burkitt lymphoma (BL) has a high mortality rate and its treatment is currently limited to chemotherapy combined with immunotherapy. The long non-coding RNA antisense non-coding RNA in the INK4 locus (ANRIL) has been identified as an oncogene that can regulate cell proliferation and apoptosis in multiple types of cancer. However, the function of ANRIL in BL remains unknown. The present study aimed to determine the effect of ANRIL on cell proliferation and apoptosis in BL. Reverse transcription-quantitative PCR was used to analyze the expression levels of ANRIL in BL cells. The effect of ANRIL knockdown on BL cells was determined using Cell Counting Kit-8, flow cytometric, western blotting, immunofluorescence staining and Hoechst staining assays. The results revealed that ANRIL silencing inhibited the proliferation and promoted the apoptosis of BL cells. In addition, the expression levels of cyclin D1, E2F transcription factor 1 and Bcl-2 were downregulated, while the expression levels of cyclin-dependent kinase inhibitor 1A, Bcl-2-associated X protein, cleaved-caspase-9/pro-caspase-9 and cleaved-caspase-3/pro-caspase-3 were upregulated. Furthermore, the knockdown of ANRIL activated the TGF-β1 signaling pathway, as evidenced by the upregulated expression levels of TGF-β1, phosphorylated (p)-SMAD2/3/SMAD2/3, p-SMAD1/SMAD1 and sphingosine-1-phosphate receptor 2. Moreover, the protective effect of ANRIL silencing in BL could be inhibited by the TGF-β receptor type I/II dual inhibitor, LY2109761. In conclusion, the findings of the present study suggested that the knockdown of ANRIL may inhibit cell proliferation and promote cell apoptosis in BL by regulating the TGF-β1 signaling pathway, which may provide a novel target for the treatment of BL.

Knock-Down of Long Non-Coding RNA ANRIL Suppresses Mouse Mesangial Cell Proliferation, Fibrosis, Inflammation via Regulating Wnt/β-Catenin and MEK/ERK Pathways in Diabetic Nephropathy

Aims Our study aimed to investigate the role of long non-coding RNA ANRIL (lnc-ANRIL) knock-down in regulating cell activities, inflammation and downstream signaling pathways in mouse mesangial cellular diabetic nephropathy (DN) model.

Methods The mouse mesangial cells (SV40-MES13 cells) were treated with high-glucose (HG) to construct cellular DN model. Lnc-ANRIL knock-down plasmid and control knock-down plasmid were transfected into HG-treated SV40-MES13 cells as Sh-ANRIL group and Sh-NC group respectively.

Results Lnc-ANRIL expression was significantly higher in HG-treated SV40-MES13 cells compared with normal glucose-treated SV40-MES13 cells and osmotic control-treated SV40-MES13 cells. Lnc-ANRIL knock-down suppressed cell proliferation and promoted cell apoptosis in HG-treated SV40-MES13 cells. As for fibrosis, lnc-ANRIL knock-down reduced fibronectin and collagen I expressions in HG-treated SV40-MES13 cells. Besides, the expressions of supernatant tumor necrosis factor-alpha (TNF-α), monocyte chemoattractant protein-1 (MCP-1), interleukin (IL)-1β, IL-6, IL-8 and IL-18 were reduced in Sh-ANRIL group compared with Sh-NC group. Furthermore, Wnt3, β-catenin, p-MEK1 and p-ERK1 expressions were suppressed in Sh-ANRIL group compared with Sh-NC group, which suggested that lnc-ANRIL knock-down inhibited Wnt/β-catenin and MEK/ERK pathways in HG-treated SV40-MES13 cells.

Conclusions Lnc-ANRIL knock-down suppresses mouse mesangial cell proliferation, fibrosis, inflammation, Wnt/β-catenin and MEK/ERK pathways in DN.

LncRNA ANRIL/miR-7-5p/TCF4 axis contributes to the progression of T cell acute lymphoblastic leukemia

Background

Antisense non-coding RNA in the INK4 locus (ANRIL) is of great importance in cell biological behaviors, and ANRIL functions in many kinds of cancers including leukemia. However, the mechanism of ANRIL in the progression of T-cell acute lymphoblastic leukemia (T-ALL) has not been clarified clearly.

Methods

qRT-PCR was performed to detect ANRIL expression in T-ALL samples. T-ALL cell lines (MOLT4, CCRF-CEM and KOPT-K1) were used as the cell models. The function of ANRIL on T-ALL cells was investigated by CCK-8 assays, Transwell assays, and apoptosis experiments in vitro. qRT-PCR, Western blot, luciferase reporter assay and RIP assay were used to confirm the interactions between ANRIL and miR-7-5p, miR-7-5p and its target gene transcription factor 4 (TCF4).

Results

ANRIL was significantly up-regulated in T-ALL samples. Its knockdown markedly inhibited viability, migration and invasion of T-ALL cells, but its overexpression exerted the opposite effects. TCF4 was proved to be a target gene of miR-7-5p. ANRIL down-regulated miR-7-5p via sponging it and in turn up-regulated TCF4.

Conclusions

LncRNA ANRIL can modulate malignant phenotypes of T-ALL cells, possibly by regulating miR-7-5p/TCF4 axis, and it serves as a potential therapeutic target for T-ALL.

LncRNA ANRIL acts as a modular scaffold of WDR5 and HDAC3 complexes and promotes alteration of the vascular smooth muscle cell phenotype

Many studies have shown that long-noncoding RNA (lncRNA) is associated with cardiovascular disease, but its molecular mechanism is still unclear. In this study, we explored the role of lncRNA ANRIL in ox-LDL-induced phenotypic transition of human aortic smooth muscle cells (HASMC). The results of quantitative fluorescence PCR showed that the expression of ANRIL in patients with coronary atherosclerotic heart disease (CAD) was significantly higher than that in normal subjects. RNA-FISH detection showed that the ANRIL expression increased in HASMC treated by ox-LDL. Ox-LDL could upregulate the expression of ANRIL and ROS and promote the phenotypic transition of HASMC. After downregulation of ANRIL by siRNA, ROS level decreased and HASMC phenotypic transition alleviated. ANRIL could act as a molecular scaffold to promote the binding of WDR5 and HDAC3 to form WDR5 and HDAC3 complexes, they regulated target genes such as NOX1 expression by histone modification, upregulated ROS level and promote HASMC phenotype transition. Therefore, we found a new epigenetic regulatory mechanism for phenotype transition of VSMC, ANRIL was a treatment target of occlusive vascular diseases.

Long non-coding RNA ANRIL enhances mitochondrial function of hepatocellular carcinoma by regulating the MiR-199a-5p/ARL2 axis

Although the roles of long non-coding RNA (lncRNA) ANRIL (Antisense non-coding RNA in the INK4A locus) have been established in various tumors, its roles in mitochondrial metabolic reprogramming of hepatocellular carcinoma (HCC) cells are still unclear. This work aims to explore lncRNA ANRIL roles in regulating the mitochondrial metabolic reprogramming of liver cancer cells. First, we found that lncRAN ANRIL expression was significantly increased in HCC tissues or cells compared with the normal adjacent tissues and normal tissues or cells. Functional experiment showed that overexpression of lncRNA ANRIL promoted mitochondrial function in HCC cells, evident by the increased mitochondrial DNA copy numbers, ATP (Adenosine triphosphate) level, mitochondrial membrane potential, and the expression levels of mitochondrial markers, while ANRIL knockdown exerted the opposite effects. Mechanistically, lncRNA ANRIL acted as a competing endogenous RNA to increase ARL2 (ADP-ribosylationfactor-like 2) expression via sponging miR-199a-5p. Notably, the miR-199a-5p/ARL2 axis is necessary for ANRIL-mediated promoting effects on HCC cell mitochondrial function. This work reveals a novel ANRIL-miR-199a-5p-ARL2 axis in HCC cell progression, which might provide potential targets for HCC treatment.

Characterization of novel LncRNA P14AS as a protector of ANRIL through AUF1 binding in human cells

Background

The CDKN2A/B locus contains crucial tumor suppressors and a lncRNA gene ANRIL. However, the mechanisms that coordinately regulate their expression levels are not clear.

Methods

Novel RNAs transcribed from the CDKN2A gene were screened by CDKN2A-specific RNA capture deep-sequencing and confirmed by Northern blotting and clone-sequencing. Long non-coding RNA (lncRNA) binding proteins were characterized by RNA pull-down combined with mass spectrometry and RNA immunoprecipitation. LncRNA functions in human cells were studied using a set of biological assays in vitro and in vivo.

Results

We characterized a novel lncRNA, P14AS with its promoter in the antisense strand of the fragment near CDKN2A exon 1b in human cells. The mature P14AS is a three-exon linear cytoplasmic lncRNA (1043-nt), including an AU-rich element (ARE) in exon 1. P14AS decreases AUF1-ANRIL/P16 RNA interaction and then increases ANRIL/P16 expression by competitively binding to AUF1 P37 and P40 isoforms. Interestingly, P14AS significantly promoted the proliferation of cancer cells and tumor formation in NOD-SCID mice in a P16-independent pattern. Moreover, in human colon cancer tissues, the expression levels of P14AS and ANRIL lncRNAs were significantly upregulated compared with the paired normal tissues.

Conclusion

A novel lncRNA, P14AS, transcribed from the antisense strand of the CDKN2A/P14 gene, promotes colon cancer development by cis upregulating the expression of oncogenic ANRIL.

Propofol upregulates miR-320a and reduces HMGB1 by downregulating ANRIL to inhibit PTC cell malignant behaviors

BACKGROUND

Our previous study states that propofol suppresses proliferation and migration of papillary thyroid cancer (PTC) cells by downregulation of lncRNA ANRIL. This study intended to probe the downstream mechanism of ANRIL in PTC with potential microRNAs (miR) and genes.

METHODS

ANRIL expression was detected in normal thyroid epithelial cells (Nthy-ori 3-1) and PTC cells (TPC-1, FTC-133, K1 and BCPAP). ANRIL expression was inhibited in TPC-1 and BCPAP cells to explore the effects of si-ANRIL in PTC malignant behaviors. The gain-and loss-of functions of ANRIL/miR-320a were performed to measure their roles in PTC. Levels of ANRIL, miR-320a, HMGB1, apoptosis- and Wnt/β-catenin and NF-κB pathways-related proteins were measured. Dual-luciferase reporter gene assay and RNA pull-down assay were applied to verify ANRIL/miR-320a/HMGB1 relation. si-ANRIL was transplanted into xenograft tumors in nude mice.

RESULTS

ANRIL was upregulated in TPC-1 and BCPAP cells. miR-320a targeted HMGB1, and ANRIL bound to miR-320a. In TPC-1 and BCPAP cells, si-ANRIL prevented PTC cell malignant behaviors, and inactivated the Wnt/β-catenin and NF-κB pathways; while si-ANRIL + miR-320a inhibition showed opposite trends. Overexpressing miR-320a promoted malignant behaviors of TPC-1 cells. In 6 μg/mL propofol-treated TPC-1 cells, miR-320a inhibition weakened propofol's inhibitory effects on PTC cell growth. After ANRIL inhibition, the volume and weight of xenograft tumors were decreased.

CONCLUSION

Propofol upregulated miR-320a and reduced HMGB1 by downregulating ANRIL and inactivating the Wnt/β-catenin and NF-κB pathways, thus preventing PTC cell malignant behaviors. This study may offer new insights in PTC prevention and treatment.

Regulating of cell cycle progression by the lncRNA CDKN2B-AS1/miR-324-5p/ROCK1 axis in laryngeal squamous cell cancer

OBJECTIVE

To evaluate the function of long non-coding RNA ANRIL (CDKN2B-AS1) in laryngeal squamous cell cancer (LSCC), and to explore the underlying mechanism.

METHODS

The expression levels of CDKN2B-AS1 in LSCC tissues and cell lines (Tu177, HN4, AMC-HN-8 and NP69) were determined by reverse transcription quantitative PCR (RT-qPCR). AMC-HN-8 cells were then transfected with siRNAs of CDKN2B-AS1. The effects of CDKN2B-AS1 on cell proliferation, cell cycle, and apoptotic protein were determined by CCK-8 assay, flow cytometry analysis, and western blot, respectively. Dual luciferase reporter assay and RNA immunoprecipitation (RIP) assay were employed to verify the targets of CDKN2B-AS1. The miR-324-5p mimics or miR-324-5p inhibitor and ROCK1 over-expression plasmids were also transfected into AMC-HN-8 cells for further analysis.

RESULTS

CDKN2B-AS1 was upregulated in LSCC tissues, and the upregulation of CDKN2B-AS1 was correlated with overall survival, advanced clinical stage, and lymph node metastasis. In AMC-HN-8 cells, the knockdown of CDKN2B-AS1 by siRNA inhibited cell viability, blocked cell cycle in G1 phase, and increased the expression levels of cyclin-dependent kinase inhibitor 1A (p21), cleaved caspase3, and cleaved PPoly (ADP-Ribose) polymerase 1. Results of dual luciferase reporter assay showed that miR-324-5p could bind to CDKN2B-AS1 or Rho-associated coiled-coil containing protein kinase 1 (ROCK1). Finally, over-expression of ROCK1 in AMC-HN-8 cells revised the inhibitory effect of CDKN2B-AS1 siRNA on cell growth.

DISCUSSION

The upregulation of CDKN2B-AS1 was correlated with overall survival, advanced clinical stage, and lymph node metastasis and promoted LSCC cell growth via miR-324-5p/ROCK1 axis.

Effect of lncRNA‑BC200 on proliferation and migration of liver cancer cells in vitro and in vivo

In recent years, the important role of long non‑​coding RNAs (lncRNAs) in the development of liver cancer has received increasing attention. The abnormal expression level of long non‑coding RNAs has been associated with the occurrence and development of liver cancer. However, the role and molecular mechanisms of lncRNAs in the development and progression of liver cancer are not fully understood. The present study aimed to clarify the function and molecular mechanism of lncRNA brain cytoplasmic 200 (BC200) in liver cancer. In the present study, it was found that BC200 expression level was higher in hepatocellular carcinoma (HCC) tissues than that in adjacent tissues. Cell function was examined by constructing BC200 knockout (KO) and BC200‑overexpression in vitro models. It was found that BC200 affected the proliferation and migration of HepG2 cells. Interestingly, it was found that BC200 affected the expression of c‑Myc protein but did not affect the mRNA expression level of c‑MYC. BC200 KO cells exhibited a reduced protein expression level of Bax protein and an increased protein expression level of Bcl‑xL. Conversely, BC200 overexpression reduced the expression of Bcl‑xL protein and increased the expression of Bax protein. Importantly, it was found that BC200 affected the formation of subcutaneous tumors in nude mice. In conclusion, the present results suggested that lncRNA BC200 may play an important role in liver cancer.

LINC00511 as a ceRNA promotes cell malignant behaviors and correlates with prognosis of hepatocellular carcinoma patients by modulating miR-195/EYA1 axis

BACKGROUND

Recently, a growing number of reports indicated that long non-coding RNAs (lncRNAs) were involved in the development of various cancers. However, the performance of LINC00511 is still limited in hepatocellular carcinoma (HCC). Thus, we attempted to assess the effect of LINC00511 and underlying mechanism in HCC progression.

METHODS

TCGA and GEO database acted as supporters to provide us clinical samples data. Overall survival (OS) analyses were plotted using Kaplan-Meier method. Five cell lines were utilized to detect LINC00511 expression level and Cell Counting Kit-8 (CCK-8), colony formation and transwell assays were conducted to examine the effects on cell behaviors. The correlations between LINC00511 and miR-195 or eyes absent homolog 1 (EYA1) were confirmed by luciferase reporter assay. Quantitative real-time PCR and western blotting were fulfilled to ascertain the mRNA and protein expression levels.

RESULTS

In this study, we found that LINC00511 was high-regulated in HCC tissue samples and cell lines, which might be linked with unfavorable prognosis of HCC patients and clinical parameters. Loss-of-function experiments determined that LINC00511 deficiency inhibited cell proliferation, colony formation and invasive activity in HepG2 cells, while gain-of-function experiments showed the counter impacts in Huh7 cells. Bioinformatics tools and luciferase reporter assays revealed that LINC00511 may act as a competing endogenous RNA (ceRNA) for miR-195 and positively correlate with EYA1, which was reinforced by rescue experiments.

CONCLUSION

Taken together, these findings indicated that LINC00511 interacted with EYA1 promoted HCC development via mediating miR-195, proposing a promising therapeutic biomarker for HCC diagnosis and prognosis.

Long Non-Coding RNA CDKN2B-AS1 Facilitates Laryngeal Squamous Cell Cancer Through Regulating miR-497/CDK6 Pathway

BACKGROUND

CDKN2B antisense RNA 1 (CDKN2B-AS1), a long noncoding RNA, was reported to play crucial roles in the progression of multiple cancers. However, the functional roles and regulatory mechanism of CDKN2B-AS1 in human laryngeal squamous cell cancer (LSCC) remain unclear. The goals of this study were to investigate biological roles and underlying mechanisms of CDKN2B-AS1 in LSCC.

METHODS

The expressions of CDKN2B-AS1, miR-497 and cyclin-dependent kinase 6 (CDK6) were detected in LSCC tissues and cell lines by real-time quantitative PCR (qRT-PCR). The effects of CDKN2B-AS1 on LSCC cell proliferation, apoptosis, migration and invasion were examined by corresponding experiments. Bioinformatics analysis and luciferase activity assay were applied to analyze the interaction between CDKN2B-AS1 and miR-497.

RESULTS

The expression of CDKN2B-AS1 was significantly higher in LSCC tissues than in adjacent normal tissues. Higher CDKN2B-AS1 was closely associated with lymph node metastasis and advanced clinical stage. Moreover, CDKN2B-AS1 knockdown by siRNA significantly inhibited the proliferation, induced cell apoptosis, and suppressed migration and invasion in LSCC cells. Mechanically, CDKN2B functions as an oncogenic lncRNA in LSCC via regulating miR-497/CDK6 axis.

CONCLUSION

The observations in this study identify CDKN2B-AS1 an oncogenic role in the tumorigenesis of LSCC by regulating miR-497/CDK6 axis and indicate that it may serve as a potential target for LSCC treatment.

Circular RNA circTRIM33-12 acts as the sponge of MicroRNA-191 to suppress hepatocellular carcinoma progression

Background

Recently, the dysregulation of circular RNA (circRNA) have been shown to have important regulatory roles in cancer development and progression, including hepatocellular carcinoma (HCC). However, the roles of most circRNAs in HCC are still unknown.

Methods

The expression of circular tripartite motif containing 33–12 (circTRIM33–12) in HCC tissues and cell lines was detected by qRT-PCR. The role of circTRIM33–12 in HCC progression was assessed by western blotting, CCK-8, flow cytometry, transwell and a subcutaneous tumor mouse assays both in vitro and in vivo. In vivo circRNA precipitation, RNA immunoprecipitation, luciferase reporter assays were performed to evaluate the interaction between circTRIM33–12 and miR-191.

Results

Here, we found that circTRIM33–12, is downregulated in HCC tissues and cell lines. The downregulation of circTRIM33–12 in HCC was significantly correlated with malignant characteristics and served as an independent risk factor for the overall survival (OS) and recurrence-free survival (RFS) of patients with HCC after surgery. The reduced expression of circTRIM33–12 in HCC cells increases tumor proliferation, migration, invasion and immune evasion. Mechanistically, we demonstrated that circTRIM33–12 upregulated TET1 expression by sponging miR-191, resulting in significantly reduced 5-hydroxymethylcytosine (5hmC) levels in HCC cells.

Conclusions

These results reveal the important role of circTRIM33–12 in the proliferation, migration, invasion and immune evasion abilities of HCC cells and provide a new perspective on circRNAs in HCC progression.

Electronic supplementary material

The online version of this article (10.1186/s12943-019-1031-1) contains supplementary material, which is available to authorized users.

Elevation of miR-191-5p level and its potential signaling pathways in hepatocellular carcinoma: a study validated by microarray and in-house qRT-PCR with 1,291 clinical samples

BACKGROUND

The miR-191-5p expression has been reported to increase in hepatocellular carcinoma (HCC), but its clinical value and exact role remain to be further clarified. Thus, a comprehensive analysis was performed in the current study to explore the underlying function of miR-191-5p in HCC.

METHODS

HCC-related expression data were collected to conduct a thorough analysis to determine the miR-191-5p expression and its clinical significance in HCC, including microarray data from the Gene Expression Omnibus and ArrayExpress database as well as quantitative real-time polymerase chain reaction (qRT-PCR) data of 178 matched clinical samples. The underlying relationship between miR-191-5p and HCC was also explored on the basis of a series of bioinformatics analyses.

RESULTS

The overall pooled meta-analysis showed an overexpression of miR-191-5p in the HCC samples (SMD=0.400, 95% CI=0.139-0.663, P=0.003), consistent with the detected result of the clinical HCC samples through the qRT-PCR analysis. Higher miR-191-5p levels were correlated with advanced TNM stages (III and IV), higher pathological grades, and metastasis. Functionally, 64 potential target genes were acquired for further mechanism analysis. Two pathways (p75 neurotrophin receptor and liver kinase B1-mediated signaling pathways), which were likely modulated by miR-191-5p, were regarded to be linked to the deterioration of HCC. Early growth response 1 and UBE2D3 were identified as the most likely targets for miR-191-5p in HCC and were commonly implied in the top enriched pathways and protein-protein network.

CONCLUSIONS

In summary, miR-191-5p may function as a tumor promoter miRNA of HCC, and the miR-191-5p inhibitor may contribute to the targeted HCC treatment in the future.

Long Noncoding RNA Antisense Noncoding RNA in the INK4 Locus Correlates With Risk, Severity, Inflammation and Infliximab Efficacy in Crohn's Disease

BACKGROUND

The aim of this study was to investigate the association of intestinal mucosa long noncoding RNA (lncRNA) antisense noncoding RNA in the INK4 locus (ANRIL) expression with disease risk, activity and inflammatory cytokines levels of Crohn's disease (CD).

METHODS

Forty-two patients with active CD (A-CD), 59 patients with CD in remission (R-CD) and 67 controls were consecutively recruited. Intestinal mucosa samples were collected from all participants at baseline and from A-CD patients at 3-months after infliximab treatment. LncRNA ANRIL level, mRNA expression of tumor necrosis factor-α, interleukin (IL)-10, IL-17, IL-23 and interferon gamma were assessed by quantitative polymerase chain reaction. C-reactive protein, erythrocyte sedimentation rate and Crohn's disease activity index were used to evaluate the disease activity of CD.

RESULTS

LncRNA ANRIL expression was decreased in patients with A-CD compared with patients with R-CD (P < 0.001) and controls (P < 0.001) and was also reduced in patients with R-CD compared with controls (P < 0.001). Receiver operating characteristic curves showed that lncRNA ANRIL expression distinguished CD, A-CD and R-CD from controls, as well as A-CD from R-CD. Additionally, lncRNA ANRIL expression was negatively associated with Crohn's disease activity index (P = 0.002), C-reactive protein (P < 0.001) and erythrocyte sedimentation rate (P = 0.001), and associated with tumor necrosis factor-α (P < 0.001), IL-17 (P < 0.001) and interferon gamma messenger RNA levels (P = 0.004) but positively associated with IL-10 messenger RNA level (P = 0.002). Furthermore, IncRNA ANRIL expression was increased after infliximab treatment compared with baseline in patients with A-CD that responded to treatment (P < 0.001) but remained stable in patients with A-CD that did not respond (P = 0.897).

CONCLUSIONS

lncRNA ANRIL downregulation in intestinal mucosa correlates with increased disease risk, higher disease activity and elevated proinflammatory cytokines levels, and its change associates with infliximab treatment response in patients with CD.