Upregulation of SOX2-activated lncRNA ANRIL promotes nasopharyngeal carcinoma cell growth

LncRNA-ANRIL regulates CDKN2A to promote malignant proliferation of Kasumi-1 cells

OBJECTIVE

This study aimed to investigate the regulatory effects of long non-coding RNA-ANRIL on CDKN2A in the cell cycle of Kasumi-1 cells and elucidate the underlying molecular mechanisms.

METHODS

ANRIL and CDKN2A expression levels were quantified using RT-qPCR in peripheral blood samples from acute myeloid leukemia (AML) patients. CDKN2A knockdown efficiency was validated via RT-qPCR, and cell cycle distribution was analyzed using flow cytometry. Cell proliferation assays were conducted with CCK-8 following palbociclib treatment and CDKN2A downregulation. RNA immunoprecipitation (RIP) identified potential ANRIL-associated targets, while western blotting assessed the expression levels of GSK3β/β-catenin/cyclin D1 signaling components and related proteins.

RESULTS

ANRIL and CDKN2A were markedly overexpressed in AML patient samples. Knockdown of ANRIL and CDKN2A led to G1 phase arrest accompanied by reduced CDK2/4/6 and cyclin D1 protein levels, while ANRIL upregulation induced the opposite effect. Palbociclib treatment for 24 h and 48 h elevated the G1 phase cell population and suppressed CDK2/4/6 and cyclin D1 protein expression, demonstrating its ability to counteract ANRIL-driven cell cycle progression. Downregulation of ANRIL and CDKN2A also suppressed the GSK3β/β-catenin signaling pathway, reducing cyclin D1 expression, whereas ANRIL upregulation reactivated this axis. Co-transfection experiments showed that simultaneous cyclin D1 suppression and ANRIL overexpression attenuated ANRIL's stimulatory effects on cell cycle progression. RIP analysis confirmed a physical interaction between ANRIL and CDKN2A. Furthermore, CDKN2A downregulation inhibited cell proliferation and reversed GSK3β/β-catenin/cyclin D1 pathway activation mediated by ANRIL upregulation.

CONCLUSION

ANRIL facilitates Kasumi-1 cell survival by modulating CDKN2A to activate the GSK3β/β-catenin/cyclin D1 signaling pathway.

Long Noncoding RNA GUSBP11 Knockdown Alleviates Nasopharyngeal Carcinoma via Regulating miR-1226-3p/TM9SF4 Axis

Purpose: Long noncoding RNAs (lncRNAs) have been confirmed related to the occurrence and progress of multiple cancers, including cervical cancer nasopharyngeal carcinoma (NPC). This study focused on assessing GUSBP11 effects on NPC progression and exploring possible mechanisms. Materials and Methods: RT-qPCR was conducted for assessing GUSBP11 levels within NPC tissues and cells. CCK-8, colony formation, and Transwell were adopted for examining GUSBP11 impacts on NPC cell proliferation and cell metastasis. RT-qPCR analysis and dual-luciferase reporter assay were conducted for judging the expression interrelation of GUSBP11 and its potential target miR-1226-3p. The same methods were carried out for verifying the inhibiting influences of miR-1226-3p upregulation and its potential target TM9SF4. Results: GUSBP11 levels were upregulated within NPC tissues and cells. GUSBP11 downregulation repressed NPC cell proliferation and cell metastasis. In addition, GUSBP11 targeted and negatively regulated miR-1226-3p. Furthermore, miR-1226-3p targeted TM9SF4 and mediated GUSBP11's impacts on TM9SF4 levels. At last, the authors proved the critical role of the GUSBP11/miR-1226-3p/TM9SF4 axis in regulating NPC progression. Conclusion: These findings indicate that downregulation of GUSBP11 alleviates NPC development by regulating the miR-1226-3p/TM9SF4 axis.

Super-enhancer driven SOX2 promotes tumor formation by chromatin re-organization in nasopharyngeal carcinoma

BACKGROUND

Nasopharyngeal carcinoma (NPC) is a malignant head and neck cancer with a high incidence in Southern China and Southeast Asia. Patients with remote metastasis and recurrent NPC have poor prognosis. Thus, a better understanding of NPC pathogenesis may identify novel therapies to address the unmet clinical needs.

METHODS

H3K27ac ChIP-seq and HiChIP was applied to understand the enhancer landscapes and the chromosome interactions. Whole genome sequencing was conducted to analyze the relationship between genomic variations and epigenetic dysregulation. CRISPRi and JQ1 treatment were used to evaluate the transcriptional regulation of SOX2 SEs. Colony formation assay, survival analysis and in vivo subcutaneous patient-derived xenograft assays were applied to explore the function and clinical relevance of SOX2 in NPC.

FINDINGS

We globally mapped the enhancer landscapes and generated NPC enhancer connectomes, linking NPC specific enhancers and SEs. We found five overlapped genes, including SOX2, among super-enhancer regulated genes, survival related genes and NPC essential genes. The mRNA expression of SOX2 was repressed when applying CRISPRi targeting different SOX2 SEs or JQ1 treatment. Next, we identified a genetic variation (Chr3:181422197, G > A) in SOX2 SE which is correlated with higher expression of SOX2 and poor survival. In addition, SOX2 was highly expressed in NPC and is correlated with short survival in patients with NPC. Knock-down of SOX2 suppressed tumor growth in vitro and in vivo.

INTERPRETATION

Our study demonstrated the super-enhancer landscape with chromosome interactions and identified super-enhancer driven SOX2 promotes tumorigenesis, suggesting that SOX2 is a potential therapeutic target for patients with NPC.

FUNDING

A full list of funding bodies that contributed to this study can be found in the Acknowledgements section.

Detection of nasopharyngeal cancer cells using the laser tweezer Raman spectroscopy technology

Nasopharyngeal cancer (NPC), which arises from the nasopharyngeal epithelial lining, is one of the common malignant otorhinolaryngological tumors in China. Due to its insidious anatomical location and highly invasive and metastatic features, it is challenging to detect NPC at early stages. In this work, a rapid laser tweezer Raman spectroscopic (LTRS) system was built and used to trap and characterize single NPC cells. Using LTRS, high-quality Raman signals of the normal nasopharyngeal cell line (NP69) and NPC cells could be successfully obtained. By analysing the Raman peaks, some unique changes were found in components, such as DNA, amide I and amide III, in NPC cells compared with normal cells. In addition, we also used a multivariate statistical algorithm to establish a diagnostic model for identifying NPC cells with an accuracy of 90.0%. These results demonstrate that LTRS in combination with the multivariate statistical analysis is a convenient and high-efficiency cell identification technology, providing a novel and rapid methodology for NPC detection at the single cell level.

MicroRNA-101-3p inhibits nasopharyngeal carcinoma cell proliferation and cisplatin resistance through ZIC5 down-regulation by targeting SOX2

This study aims to explore the mechanism of microRNA (miR)-101-3p-mediated SOX2/ZIC5 axis in the progression of cisplatin resistance of nasopharyngeal carcinoma (NPC). ZIC5 expression was analyzed with a bioinformatics database and detected in NPC cell lines. Cisplatin-resistant cells (HNE-1/DDP and C666-1/DDP) were transfected with sh-ZIC5, sh-SOX2, sh-SOX2 + pcDNA3.1-ZIC5, or miR-101-3p Agomir + pcDNA3.1-SOX2. MiR-101-3p, SOX2, and ZIC5 expression was assessed after transfection, and cancer associated phenotypes were evaluated after cisplatin treatment. The potential relationships among miR-101-3p, SOX2, and ZIC5 were analyzed. A xenograft mouse model of NPC was established with HNE-1 cells stably transfected or not transfected with oe-ZIC5 and subjected to tail vein injection of miR-101-3p Agomir and intraperitoneal injection of cisplatin. Overexpression of ZIC5 was found in cisplatin-resistant NPC cells. Downregulating ZIC5 in NPC cells decreased cell viability, promoted apoptosis, and reduced cisplatin resistance. SOX2 had a binding site on ZIC5, and SOX2 promoted proliferation, migration, and cisplatin resistance and inhibited cell apoptosis by up-regulating ZIC5. Mechanistically, miR-101-3p was decreased in cisplatin-resistant NPC cells and negatively targeted SOX2. Overexpression of miR-101-3p inhibited tumor growth and cisplatin resistance in xenograft mouse model, which was reversed by ZIC5 overexpression. In conclusion, the miR-101-3p/SOX2/ZIC5 axis was implicated in cancer associated phenotypes and cisplatin resistance in NPC.

METTL3-stabilized super enhancers-lncRNA SUCLG2-AS1 mediates the formation of a long-range chromatin loop between enhancers and promoters of SOX2 in metastasis and radiosensitivity of nasopharyngeal carcinoma

BACKGROUND

Super enhancers (SE) play pivotal roles in cell identity and diseases occur including tumorigenesis. The depletion of SE-associated lncRNA transcripts, also known as super-lncRNA, causes the activity of SE to be dysregulated.

METHODS

We screened and identified an elevated metastasis-associated SE-lncRNA SUCLG2-AS1 in nasopharyngeal carcinoma (NPC) using RNA-sequencing, real-time quantitative polymerase chain reaction (RT-qPCR) and bioinformatics. Western blotting, RT-qPCR, methylated RNA immunoprecipitation (MeRIP), RNA immunoprecipitation, chromatin immunoprecipitation, RNA pull-down and 3C (chromosome conformation capture assays) were used for mechanistic studies.

RESULTS

SUCLG2-AS1 was correlated with a poor prognosis. SUCLG2-AS1 promotes NPC cell invasion and metastasis while repressing apoptosis and radiosensitivity in vitro and in vivo. Mechanistically, high SUCLG2-AS1 expression occurred in an m6A-dependent manner. SUCLG2-AS1 was found to be located in the SE region of SOX2, and it regulated the expression of SOX2 via long-range chromatin loop formation, which via mediating CTCF (transcription factor) occupied the SE and promoter region of SOX2, thus regulating the metastasis and radiosensitivity of NPC.

CONCLUSIONS

Taken together, our data suggest that SUCLG2-AS1 may serve as a novel intervention target for the clinical treatment of NPC.

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.

SOX2-associated signaling pathways regulate biological phenotypes of cancers

SOX2 is a transcription factor involved in multiple stages of embryonic development. In related reports, SOX2 was found to be abnormally expressed in tumor tissues and correlated with clinical features such as TNM staging, tumor grade, and prognosis in patients with various cancer types. In most cancer types, SOX2 is a tumor-promoting factor that regulates tumor progression and metastasis primarily by maintaining the stemness of cancer cells. In addition, SOX2 also regulates the proliferation, apoptosis, invasion, migration, ferroptosis and drug resistance of cancer cells. However, SOX2 acts as a tumor suppressor in some cases in certain cancer types, such as gastric and lung cancer. These key regulatory functions of SOX2 involve complex regulatory networks, including protein-protein and protein-nucleic acid interactions through signaling pathways and noncoding RNA interactions, modulating SOX2 expression may be a potential therapeutic strategy for clinical cancer patients. Therefore, we sorted out the phenotypes related to SOX2 in cancer, hoping to provide a basis for further clinical translation.

KTN1-AS1, a SOX2-mediated lncRNA, activates epithelial-mesenchymal transition process in esophageal squamous cell carcinoma

Kinectin 1 antisense RNA 1 (KTN1-AS1), a long non-coding RNA (lncRNA), has been proved to have tumor-promoting properties and its expression is enhanced in several human tumors. However, the role of KTN1-AS1 in the pathogenesis of esophageal squamous cell carcinoma (ESCC) remains unknown. This study aimed to investigate the expression status, functional roles, and molecular mechanisms of KTN1-AS1 in the development of ESCC. Considerable upregulation of KTN1-AS1 was confirmed in esophageal cancer cells and ESCC tissues and its expression was associated with TNM stage, pathological differentiation, and lymph node metastasis. SOX2 directly activated transcription of KTN1-AS1, and overexpression of KTN1-AS1 facilitated ESCC cells proliferation and invasion in vitro and in vivo. Furthermore, KTN1-AS1 could bind to retinoblastoma binding protein 4 (RBBP4) in the nucleus and enhanced its binding with histone deacetylase 1 (HDAC1), thereby activating the epithelial-mesenchymal transition (EMT) process through downregulating E-cadherin expression at the epigenetic level. In conclusion, KTN1-AS1, induced by SOX2, acts as a tumor-promoting gene and may serve as a potential therapeutic and prognostic biomarker for ESCC.

Non-coding RNA dysregulation in skin cancers

Skin cancers are the most common cancers worldwide. They can be classified in melanoma and non-melanoma skin cancer (NMSC), the latter includes squamous cell carcinoma (SCC), basal cell carcinoma (BCC) and merkel cell carcinoma (MCC). In recent years, the crucial role of non-coding RNAs (ncRNAs) in skin cancer pathogenesis has become increasingly evident. NcRNAs are functional RNA molecules that lack any protein-coding activity. These ncRNAs are classified based on their length: small, medium-size, and long ncRNAs. Among the most studied ncRNAs there are microRNAs (miRNAs), long non-coding RNAs (lncRNAs), and circular RNA (circRNAs). ncRNAs have the ability to regulate gene expression at transcriptional and post-transcriptional levels and are involved in skin cancer cell proliferation, angiogenesis, invasion, and metastasis. Many ncRNAs exhibit tissue- or cell-specific expression while others have been correlated to tumor staging, drug resistance, and prognosis. For these reasons, ncRNAs have both a diagnostic and prognostic significance in skin cancers. Our review summarizes the functional role of ncRNAs in skin cancers and their potential clinical application as biomarkers.

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.

Long non-coding RNAs regulating multiple proliferative pathways in cancer cell

Long non-coding RNAs (lncRNAs) belong to an extremely heterogeneous class of non-coding RNAs with a length ranging from 200 to 100,000 bp. They modulate a series of cellular pathways in both physiological and pathological context. It is no coincidence that they are expressed in an aberrant way in pathologies such as cancer, so as to deserve to be subclassified as oncogenes or tumor suppressors. These molecules are also involved in the regulation of cancer cell proliferation. Several lncRNAs are able to modulate cell growth both positively and negatively, and in this review we have focused on a small group of them, characterized by the simultaneous action on different pathways regulating cell proliferation. They have been considered in the light of their behavior in three different subtypes of proliferative pathways that we can define as (I) tumor suppressor, (II) oncogenic and (III) transcriptionally-driven. More specifically, we have characterized some lncRNAs considered oncogenes (such as H19, linc-ROR, MALAT1, HULC, HOTAIR and ANRIL), tumor suppressors (such as MEG3 and lincRNA-p21), and both oncogenes/tumor suppressors (UCA1 and TUG1) in a little more detail. As can be understood from the review, the interactions between lncRNAs and their molecular targets, only in the context of controlling cell proliferation, give rise to an intricate molecular network, the understanding of which, in the future, will certainly be of help for the treatment of molecular diseases such as cancer.

LncRNA SNHG16 Facilitates Nasopharyngeal Carcinoma Progression by Acting as ceRNA to Sponge miR-520a-3p and Upregulate MAPK1 Expression

Background

Accumulating evidence shows that lncRNAs are widely involved cellular processes of various tumors. The aim of this study was to explore the potential role and molecular mechanism of lncRNA SNHG16 in nasopharyngeal carcinoma (NPC).

Methods

SNHG16, miR-520a-3p, and MAPK1 levels were measured by RT-qPCR assay. CCK-8, colony formation, transwell, and flow cytometry assays were adopted to analyze the proliferation, migration, invasion, and apoptosis of NPC cell lines (SUNE1 and 5–8F). Murine xenograft model was used to investigate tumor growth and metastasis in vivo. Immunohistochemical staining was employed to evaluate the levels of Bcl-2, cleaved caspase-3, Bax, and Ki-67. Dual-luciferase reporter assays were conducted to analyze the binding ability between miR-520a-3p and SNHG16 or MAPK1.

Results

SNHG16 was overexpressed in NPC tissues and cells. High SNHG16 expression indicated a poor prognosis. SNHG16 knockdown could cause significant inhibition on cell proliferation and metastasis, induce cell apoptosis in NPC cells, and repressed tumor growth and metastasis in vivo. Additionally, SNHG16 could directly bind to miR-520a-3p, thus positively regulating MAPK1 expression. Moreover, functional analysis indicated that miR-520a-3p exerted a tumor-suppressing role in NPC progression. Rescue assays demonstrated that MAPK1 upregulation could abrogate the inhibitory effects on NPC cell proliferation and metastasis, as well as the promoting effects on NPC cell apoptosis caused by SNHG16 knockdown. In conclusion, SNHG16 contributed to the proliferation and metastasis of NPC cells by modulating the miR-520a-3p/MAPK1 axis.

Conclusion

These results suggest that SNHG16 acts as an oncogene in the progression of NPC via modulating the miR-520a-3p/MAPK1 axis.

Long non-coding RNAs and cancer metastasis: Molecular basis and therapeutic implications

Cancer metastasis, defined by the epithelial to mesenchymal transition (EMT) of tumor cells, disseminates from the primary site to progressively colonize in distant tissues, and accounts for most cancer-associated deaths. However, studies on the molecular basis of cancer metastasis are still in their infancy. Besides genetic mutations, accumulating evidence indicates that epigenetic alterations also contribute in a major way to the refractory nature of cancer metastasis. Considered as one of the essential epigenetic regulators, long non-coding RNAs (lncRNAs) can act as signaling regulators, decoys, guides and scaffolds, modulating key molecules in every step of cancer metastasis including dissemination of carcinoma cells, intravascular transit, and metastatic colonization. Although still having limited clinical application, it is encouraging to witness that several lncRNAs, including CCAT1 and HOTAIR, are under clinical evaluation as potential biomarkers for cancer staging and assessment of metastatic potential. In this review, we focus on the molecular mechanisms underlying lncRNAs in the regulation of cancer metastasis and discuss their clinical potential as novel therapeutic targets as well as their diagnostic and prognostic significance for cancer treatment. Gaining clear insights into the detailed molecular basis underlying lncRNA-modulated cancer metastasis may provide previously unrecognized diagnostic and therapeutic strategies for metastatic patients.

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.

TIGIT/PVR and LncRNA ANRIL dual-targetable PAMAM polymeric nanoparticles efficiently inhibited the hepatoma carcinoma by combination of immunotherapy and gene therapy

Herein, a novel polymeric nanoparticle was designed to inhibit hepatoma carcinoma by simultaneously targeting the T cell immunoreceptor with Ig and ITIM domains (TIGIT)/poliovirus receptor (PVR) and long noncoding RNAs antisense noncoding RNA in the INK4 locus (LncRNA ANRIL). Firstly, the siANRIL-loaded nanoparticles (NP-siANRIL) was developed by methoxy-poly (ethylene glycol)-polyamidoamine (mPEG-PAMAM) and polyamidoamine-poly (ethylene glycol)-disulphide bond-carboxyl (PAMAM-PEG-S₂-COOH) using the self-assembly method. Then the ^DTBP-3 peptide, a newly developed identified peptide which could occupy the binding interface and effectively block the interaction of TIGIT with its ligand PVR, was further conjugated on the surface of NP-siANRIL via the glutathione (GSH)-sensitive disulphide linkage. In this way, the binding ability of ^DTBP-3 to TIGIT was remained once they were entrapped into the tumour tissues which were abundant of GSH. The present study demonstrated that ^DTBP-3NP-siANRIL exhibited an excellent anti-tumour effect on hepatoma carcinoma in vivo by simultaneously inhibited the expression of miR-203a and its downstream genes and increased the percentages of NK cells and T cells. In a word, the present study has presented a novel strategy for treatment of hepatoma carcinoma by simultaneously targeting of TIGIT/PVR and LncRNA ANRIL.

LINC00667 Sponges miR-4319 to Promote the Development of Nasopharyngeal Carcinoma by Increasing FOXQ1 Expression

Accumulating evidence has indicated that lncRNAs regulate various biological and pathological processes in diverse malignant tumors. The roles of LINC00667 in cancer development have been explored in glioma, hepatocellular carcinoma and non-small cell lung cancer, but not in nasopharyngeal carcinoma (NPC). In the present study, we characterize the role and molecular mechanism of LINC00667 in NPC progression. It was found that LINC00667 was overexpressed in NPC cells compared to normal cells. Silencing LINC00667 suppressed the proliferation, migration, invasion and epithelial mesenchymal transition (EMT) in NPC cells. In addition, bioinformatics analysis revealed that LINC00667 acted as a ceRNA to absorb miR-4319. Further investigations illustrated that miR-4319 had low expression in NPC cells and functioned as a tumor suppressor in the progression of NPC. Mechanistic study identified forkhead box Q1 (FOXQ1) as a functional target of miR-4319. The effect of LINC00667 in NPC development was mediated by the miR-4319/FOXQ1 axis. Analysis on tumorxenograft mouse model demonstrated that knockdown of LINC00667 repressed NPC tumor growth in vivo and confirmed the in vitro results. Our present study suggested that LINC00667 promoted the malignant phenotypes of NPC cells by competitively binding to miR-4319 to up-regulate FOXQ1 expression. Our results reveled that LINC00667 could be a diagnostic and therapeutic target for NPC patients.

MicroRNA-505, Suppressed by Oncogenic Long Non-coding RNA LINC01448, Acts as a Novel Suppressor of Glycolysis and Tumor Progression Through Inhibiting HK2 Expression in Pancreatic Cancer

Background: MicroRNAs (miRNAs) and long non-coding RNAs (lncRNAs) play vital regulatory roles in pancreatic cancer (PC) initiation and progression. We aimed to explore the biological functions and underlying mechanisms of miR-505-3p (miR-505) in PC.

Methods: We first screened miRNA expression profiles using microarray in PC tissues and normal tissues, and then studied the function and underlying mechanism of miR-505. Moreover, we evaluated the regulatory effect of lncRNA LINC01448 on miR-505.

Results: We demonstrated miR-505 that was significantly downregulated in PC tissues. We further revealed that miR-505 significantly inhibited cell proliferation, invasion, sphere formation, glucose consumption, and lactate production by targeting HK2. In addition, overexpression of miR-505 led to tumor growth inhibition in vivo, demonstrating that it acts as a tumor suppressor in PC. LINC01448 was identified as an oncogenic lncRNA that could reduce miR-505 expression. Subsequent studies confirmed that LINC01448 enhanced cell proliferation, invasion, sphere formation, glucose consumption, and lactate production by regulating the miR-505/HK2 pathway.

Conclusions: These findings demonstrated that miR-505, suppressed by LINC01448, could function as a key tumor suppressor by targeting HK2 in PC, elucidating an important role of the LINC01448/miR-505/HK2 pathway in regulating PC glycolysis and progression.

The Role of Noncoding RNAs in the Regulation of Anoikis and Anchorage-Independent Growth in Cancer

Cancer is a global health concern, and the prognosis of patients with cancer is associated with metastasis. Multistep processes are involved in cancer metastasis. Accumulating evidence has shown that cancer cells acquire the capacity of anoikis resistance and anchorage-independent cell growth, which are critical prerequisite features of metastatic cancer cells. Multiple cellular factors and events, such as apoptosis, survival factors, cell cycle, EMT, stemness, autophagy, and integrins influence the anoikis resistance and anchorage-independent cell growth in cancer. Noncoding RNAs (ncRNAs), such as microRNAs (miRNAs) and long noncoding RNAs (lncRNAs), are dysregulated in cancer. They regulate cellular signaling pathways and events, eventually contributing to cancer aggressiveness. This review presents the role of miRNAs and lncRNAs in modulating anoikis resistance and anchorage-independent cell growth. We also discuss the feasibility of ncRNA-based therapy and the natural features of ncRNAs that need to be contemplated for more beneficial therapeutic strategies against cancer.

Long noncoding RNA ANRIL as a novel biomarker in human cancer

The long noncoding RNA ANRIL, located in the human chromosome 9p21 region, has been reported to be involved in tumor progression. ANRIL regulates gene expression via recruiting PRC2 or titrating miRNA; it also participates in signaling pathways. Evidence has indicated that ANRIL is overexpressed in many cancer types and is capable of enhancing cell proliferation and cell cycle progression and inhibiting apoptosis and senescence. ANRIL has the potential to serve as a biomarker for diagnosis and prognosis in cancer. In this article we focus on recent advances in studies of the oncogenic role of ANRIL and its potential role in cancer medicine.

Long Noncoding RNA DANCR Regulates Cell Proliferation by Stabilizing SOX2 mRNA in Nasopharyngeal Carcinoma

The long noncoding RNA DANCR (differentiation antagonizing non-protein coding RNA) displays aberrant expression in various cancers. However, its clinical value and functional mechanisms in nasopharyngeal carcinoma (NPC) remain poorly understood. We found that DANCR is dramatically up-regulated in human NPC, and that it is an indicator for poor survival prognosis. DANCR knockdown suppressed cell proliferation, colony formation in vitro, and tumorigenicity in vivo. Mechanistic analyses demonstrated that DANCR could bind to RNA-binding protein 3 (RBM3) protein and stabilize SOX2 mRNA, resulting in NPC cell proliferation. Our findings indicate that DANCR functions as an oncogene and a potential therapeutic target for NPC.

Emerging Roles for the INK4a/ARF (CDKN2A) Locus in Adipose Tissue: Implications for Obesity and Type 2 Diabetes

Besides its role as a cell cycle and proliferation regulator, the INK4a/ARF (CDKN2A) locus and its associated pathways are thought to play additional functions in the control of energy homeostasis. Genome-wide association studies in humans and rodents have revealed that single nucleotide polymorphisms in this locus are risk factors for obesity and related metabolic diseases including cardiovascular complications and type-2 diabetes (T2D). Recent studies showed that both p16^INK4a-CDK4-E2F1/pRB and p19^ARF-P53 (p14^ARF in humans) related pathways regulate adipose tissue (AT) physiology and adipocyte functions such as lipid storage, inflammation, oxidative activity, and cellular plasticity (browning). Targeting these metabolic pathways in AT emerged as a new putative therapy to alleviate the effects of obesity and prevent T2D. This review aims to provide an overview of the literature linking the INK4a/ARF locus with AT functions, focusing on its mechanisms of action in the regulation of energy homeostasis.

Diagnostic and Prognostic Indications of Nasopharyngeal Carcinoma

Nasopharyngeal carcinoma (NPC) is a disease that is highly associated with the latent infection of Epstein-Barr virus. The absence of obvious clinical signs at the early stage of the disease has made early diagnosis practically impossible, thereby promoting the establishment and progression of the disease. To enhance the stride for a reliable and less invasive tool for the diagnosis and prognosis of NPC, we synopsize biomarkers belonging to the two most implicated biological domains (oncogenes and tumor suppressors) in NPC disease. Since no single biomarker is sufficient for diagnosis and prognosis, coupled with the fact that the known established methods such as methylation-specific polymerase chain reaction (PCR), multiplex methylation-specific PCR, microarray assays, etc., can only accommodate a few biomarkers, we propose a 10-biomarker panel (KIT, LMP1, PIKC3A, miR-141, and miR-18a/b (oncogenic) and p16, RASSF1A, DAP-kinase, miR-9, and miR-26a (tumor suppressors)) based on their diagnostic and prognostic values. This marker set could be explored in a multilevel or single unified assay for the diagnosis and prognosis of NPC. If carefully harnessed and standardized, it is hoped that the proposed marker set would help transform the diagnostic and prognostic realm of NPC, and ultimately, help prevent the life-threatening late-stage NPC disease.

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 ZNF667-AS1 Promotes ABLIM1 Expression by Adsorbing micro RNA-1290 to Suppress Nasopharyngeal Carcinoma Cell Progression

Background

Recently, long non-coding RNAs (lncRNAs) have been elucidated to play essential roles in cancers, and the recognition of lncRNA expression patterns in nasopharyngeal carcinoma (NPC) may be helpful for indicating novel mechanisms underlying NPC carcinogenesis. Herein, we conducted this study to probe into the function of lncRNA ZNF667-AS1 in NPC progression with the involvement of microRNA-1290 (miR-1290) and actin-binding LIM protein 1 (ABLIM1).

Materials and Methods

In silico analysis screened differentially expressed genes and miRNAs in NPC and predicted potential mechanisms. ZNF667-AS1 expression was detected in NPC tissues and cells. The gain-and-loss function assays were performed to explore the effects of lncRNA ZNF667-AS1 and miR-1290 in NPC cell biological behaviors. In vivo experiments were further conducted to confirm the in vitro results.

Results

In silico analysis predicted that ZNF667-AS1 was diminished in NPC, which may downregulate ABLIM1 through sponging miR-1290. ZNF667-AS1 was poorly expressed in NPC tissues and cells, and overexpression of ZNF667-AS1 inhibited growth of NPC cells. ZNF667-AS1 competitively bound with miR-1290, thereby upregulating ABLIM1. miR-1290 resulted in the promotion of NPC cell progression by suppressing ABLIM1. Overexpression of ZNF667-AS1 or suppression of miR-1290 inhibited tumorigenicity of NPC cells in vivo.

Conclusion

This study highlights that lncRNA ZNF667-AS1 promotes ABLIM1 expression by sponging miR-1290 to suppress NPC cell progression.

Homeodomain protein DLX4 facilitates nasopharyngeal carcinoma progression via up-regulation of YB-1

Nasopharyngeal carcinoma (NPC) is a malignant tumor in nasopharynx tissues and lacks effective treatment strategies. Dysregulation of distal-less homeobox 4 (DLX4) participates in the development of tumors. Understanding the regulatory mechanism of DLX4 in NPC progression may address this issue. Here, we first identified an up-regulation of DLX4 in NPC cell lines compared to normal epithelial cells. Data from colony formation and transwell assays showed that knockdown of DLX4 inhibited cell proliferation and invasion of NPC, respectively. Moreover, DLX4 knockdown blocked the cell cycle of NPC at G1 phase, suggesting the antitumor effect of DLX4 knockdown on NPC. The downstream target of DLX4 was identified as Y-box binding protein 1 (YB-1), whose expression was increased by over-expression of DLX4, while decreased by knockdown of DLX4. The binding capacity between DLX4 and YB-1 was verified by chromatin immunoprecipitation (ChIP), and the result showed that DLX4 could not directly bind to the promoter of YB-1. Mechanically, YB-1 over-expression reversed the effects of DLX4 knockdown on cell proliferation, cell cycle arrest and cell invasion of NPC. In conclusion, our findings indicated that DLX4 promoted NPC progression via up-regulation of YB-1, which would shed light on therapeutic schedule in NPC.

The Long Non-Coding RNA Prader Willi/Angelman Region RNA5 (PAR5) Is Downregulated in Anaplastic Thyroid Carcinomas Where It Acts as a Tumor Suppressor by Reducing EZH2 Activity

Anaplastic thyroid carcinoma (ATC) represents one the most aggressive neoplasias in humans, and, nowadays, limited advances have been made to extend the survival and reduce the mortality of ATC. Thus, the identification of molecular mechanism underlying its progression is needed. Here, we evaluated the long non-coding RNA (lncRNA) expression profile of nine ATC in comparison with five normal thyroid tissues by a lncRNA microarray. By this analysis, we identified 19 upregulated and 28 downregulated lncRNAs with a fold change >1.1 or <−1.1 and p-value < 0.05, in ATC samples. Some of them were subsequently validated by qRT-PCR. Then, we investigated the role of the lncRNA Prader Willi/Angelman region RNA5 (PAR5), drastically and specifically downregulated in ATC. The restoration of PAR5 reduces proliferation and migration rates of ATC-derived cell lines indicating that its downregulation contributes to thyroid cancer progression. Our results suggest that PAR5 exerts its anti-oncogenic role by impairing Enhancer of Zeste Homolog 2 (EZH2) oncogenic activity since we demonstrated that PAR5 interacts with it in thyroid cancer cell lines, reducing EZH2 protein levels and its binding on the E-cadherin promoter, relieving E-cadherin from the negative regulation by EZH2. Consistently, EZH2 is overexpressed in ATC, but not in differentiated thyroid carcinomas. The results reported here define a tumor suppressor role for PAR5 in undifferentiated thyroid neoplasias, further highlighting the pivotal role of lncRNAs in thyroid carcinogenesis.

Long noncoding RNA ZFAS1 promotes tumorigenesis and metastasis in nasopharyngeal carcinoma by sponging miR-892b to up-regulate LPAR1 expression

OBJECTIVE

In this study, we explored the NPC-specific expression of ZFAS1 and the mechanism of ZFAS1-mediated growth, aggressiveness and tumorigenesis in NPC.

METHODS

The expression profile of lncRNAs was detected in NPC tissues and matching para-carcinoma tissues using microarray analysis. LncRNA-miRNA and miRNA-mRNA interaction networks were constructed using the miRcode v11 and TargetScanHuman v7.2 web server and then validated using dual-luciferase assay. Western blot and RT-qPCR were performed to detect protein and RNA expression. The effects of ZFAS1, miR-892b and LPAR1 dysregulation on the proliferative, migratory and invasive abilities of NPC cells were observed using colony formation, cell counting kit-8 (CCK-8) and transwell assays in vitro. In vivo, a xenograft nude mouse model was established to detect the impact of ZFAS1 dysregulation on the tumorigenicity of NPC cells.

RESULTS

The expression of multiple lncRNAs, of which ZFAS1 was up-regulated, was dysregulated in NPC tissues. ZFAS1 directly targeted miR-892b, and miR-892b negatively regulated the expression of downstream LPAR1. The proliferation, migration and invasion of NPC cells could be largely enhanced by the downregulation of miR-892b as well as the up-regulation of ZFAS1 and LPAR1, while the overexpression of miR-892b and the downregulation of ZFAS1 and LPAR1 decreased these abilities. In nude mice, the growth of tumour xenografts formed by HONE1 cells was significantly suppressed when ZFAS1 was silenced.

CONCLUSION

The study demonstrated that lncRNA ZFAS1 may act as a promoter of tumorigenesis and metastasis in nasopharyngeal carcinoma, by up-regulating the expression of LPAR1 in a miR-892b-dependent manner.

Tumor suppressor and oncogenic role of long non-coding RNAs in cancer

Non-coding RNAs are RNA molecules that are not translated into the protein, making up the vast majority of the human genome. Long non-coding RNAs (lncRNA) are in the RNA group that has longer than 200 nucleotides, and non-protein coding transcripts. In recent years, the potential has attracted considerable attention as new important biological regulators. LncRNAs play a critical role in regulating the activity and localization of proteins, processing the production of small RNAs, and processing other RNAs. They are also involved in cell differentiation, cell cycle, proliferation, apoptosis, migration and invasion by modulation of gene expression. Abnormal expression of LncRNAs has an important role in the function of oncogenes and tumor suppressor genes. Recently, there has been an increasing number of studies on the tumorigenic effects of specific lncRNAs in the initiation and progression of cancer. In this review, general information about lncRNAs is provided, including the biological importance of lncRNAs in cancer diseases and their potential development in therapeutic applications.

LINC01116 accelerates nasopharyngeal carcinoma progression based on its enhancement on MYC transcription activity

Long noncoding RNAs (lncRNAs) have been demonstrated to be frequently involved in the development of cancers, whereas only a few of them was investigated in nasopharyngeal carcinoma (NPC). Here, we found that LINC01116 was highly expressed in NPC cell lines, and inhibition of LINC01116 notably restrained cell viability, proliferation, and migration in NPC cells. Besides, we unveiled that LINC01116 was mainly distributed in the cytoplasm of NPC cells. Surprisingly, the cytoplasmic LINC01116 could directly interact with the 5'UTR of MYC mRNA, whereas such interaction had no influence on MYC mRNA expression, but facilitated MYC mRNA translation so as to enhance MYC protein level in NPC cells. Moreover, LINC01116 per se had no impact on the transcription of MYC targets but affected their expression through MYC-dependent manner. Furthermore, MYC overexpression offset the suppression of LINC01116 silence on NPC development. In turn, we discovered that MYC could also serve as the transcriptional activator of LINC01116 in NPC cells. By and large, our findings elucidated a LINC01116/MYC feedback loop in accelerating the tumorigenesis of NPC, revealing a promising target to establish novel biomarkers for NPC patients.

Long noncoding RNAs in cancer: From discovery to therapeutic targets

Long noncoding RNAs (lncRNAs) have recently gained considerable attention as key players in biological regulation; however, the mechanisms by which lncRNAs govern various disease processes remain mysterious and are just beginning to be understood. The ease of next-generation sequencing technologies has led to an explosion of genomic information, especially for the lncRNA class of noncoding RNAs. LncRNAs exhibit the characteristics of mRNAs, such as polyadenylation, 5' methyl capping, RNA polymerase II-dependent transcription, and splicing. These transcripts comprise more than 200 nucleotides (nt) and are not translated into proteins. Directed interrogation of annotated lncRNAs from RNA-Seq datasets has revealed dramatic differences in their expression, largely driven by alterations in transcription, the cell cycle, and RNA metabolism. The fact that lncRNAs are expressed cell- and tissue-specifically makes them excellent biomarkers for ongoing biological events. Notably, lncRNAs are differentially expressed in several cancers and show a distinct association with clinical outcomes. Novel methods and strategies are being developed to study lncRNA function and will provide researchers with the tools and opportunities to develop lncRNA-based therapeutics for cancer.

Long noncoding RNA SMAD5-AS1 acts as a microRNA-106a-5p sponge to promote epithelial mesenchymal transition in nasopharyngeal carcinoma

Nasopharyngeal carcinoma (NPC) is a malignant epithelial cancer of the head and neck with high prevalence in southern China, which is accompanied by notable invasiveness and metastasis. Long noncoding RNAs (lncRNAs) participate in the progression of various cancers including NPC. Microarray-based analysis identified highly expressed lncRNA mothers against decapentaplegic homolog 5 (SMAD5)-antisense RNA 1 (AS1) related to NPC. Interestingly, it is found that SMAD5-AS1 competitively bound to microRNA (miR)-106a-5p to regulate SMAD5. Herein, the study aimed to clarify the role of SMAD5-AS1/miR-106a-5p/SMAD5 axis in the process of epithelial mesenchymal transition (EMT) in NPC. SMAD5-AS1 was highly expressed and miR-106a-5p was poorly expressed in NPC tissues and cell lines. The NPC cells were treated with a series of small interfering RNAs, mimics, or inhibitors to explore the effects of SMAD5-AS1, SMAD5, and miR-106a-5p on EMT, cell proliferation, migration, and invasion in NPC. Of note, SMAD5-AS1 silencing or miR-106a-5p overexpression reduced expression of N-cadherin, matrix metallopeptidase 9, Snail, and Vimentin while elevating E-cadherin expression, thus inhibiting EMT, cell proliferation, migration, and invasion in NPC by down-regulation of SMAD5. Moreover, SMAD5 silencing could reduce the ability of EMT induced by SMAD5-AS1 up-regulation. SMAD5-AS1 silencing or miR-106a-5p elevation inhibited tumorigenesis in nude mice. Taken together, SMAD5-AS1 silencing suppressed EMT, cell proliferation, migration, and invasion in NPC by elevating miR-106a-5p to down-regulate SMAD5, which provided a novel therapeutic target for NPC treatment.-Zheng, Y.-J., Zhao, J.-Y., Liang, T.-S., Wang, P., Wang, J., Yang, D.-K., Liu, Z.-S. Long noncoding RNA SMAD5-AS1 acts as a microRNA-106a-5p sponge to promote epithelial mesenchymal transition in nasopharyngeal carcinoma.

High Positive Correlations between ANRIL and p16-CDKN2A/p15-CDKN2B/p14-ARF Gene Cluster Overexpression in Multi-Tumor Types Suggest Deregulated Activation of an ANRIL-ARF Bidirectional Promoter

The CDKN2B-AS1 gene, also called ANRIL, is located at the human CDKN2A/B locus at 9p21.3 and transcribed by RNA polymerase II into a long non-coding RNA of 3834 bp. The CDKN2B-AS1 gene overlaps a critical region of 125 kb covering the CDKN2B gene. The CDKN2A/B locus encompasses three major tumor suppressors juxtaposed and joined into a p16-CDKN2A/p15-CDKN2B/p14-ARF gene cluster. CDKN2A encodes splice variants p16-CDKN2A and p14-ARF, and CDKN2B encodes p15-CDKN2B. ANRIL shares a bidirectional promoter with the p14-ARF gene and is transcribed from the opposite strand to the cluster. We performed an analysis of the expression level of ANRIL and tumor suppressor p16-CDKN2A, p15-CDKN2B, and p14-ARF genes using quantitative RT-PCR in a multitumor panel. We observed the overexpression of the four genes ANRIL, p16-CDKN2A, p15-CDKN2B, and p14-ARF in the great majority of the 17 different cancer types. ANRIL was upregulated in 13/17 tumors compared to normal tissues, ranging from 5% (prostate cancer) to 91% (cervix cancer), with variable expression of p16-CDKN2A, p15-CDKN2B, and p14-ARF genes. A high positive correlation was identified between levels of expression of ANRIL and the three tumor suppressors. The strongest positive association was observed with p14-ARF (p < 0.001) in all but one (lung squamous cell carcinoma) of the examined tumor types. This correlation suggests coordinated deregulated mechanisms in all cancer types through aberrant activation of a bidirectional p14-ARF/ANRIL promoter. Furthermore, significant positive correlation was unexpectedly established in prostatic carcinomas, in contradiction with previous data.

Long Noncoding RNAs and Messenger RNAs Expression Profiles Potentially Regulated by ZBTB7A in Nasopharyngeal Carcinoma

Our previous studies showed that ZBTB7A played an important role in promoting nasopharyngeal carcinoma (NPC) progression. However, molecular mechanisms of different levels of ZBTB7A are still unclear. It is necessary to search molecular markers which are closely connected with ZBTB7A. We selected NPC sublines CNE2 with stably transfecting empty plasmid (negative control, NC) and short hair RNA (shRNA) plasmid targeting ZBTB7A as research objectives. Microarray was used to screen differentially expressed long noncoding RNAs (lncRNAs) and messenger RNAs (mRNAs) via shRNA-CNE2 versus NC-CNE2. Quantitative PCR (qPCR) was used to validate lncRNAs and mRNAs from the sublines, chronic rhinitis, and NPC tissues. Bioinformatics was used to analyze regulatory pathways which were connected with ZBTB7A. The 1501 lncRNAs (long noncoding RNAs) and 1275 differentially expressed mRNAs were upregulated or downregulated over 2-fold. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis revealed that the upregulated or downregulated carbohydrate and lipid metabolisms probably involved in carcinogenicity of shRNA-CNE2 (P-value cut-off was 0.05). In order to find the molecular mechanisms of ZBTB7A, we validated 12 differentially expressed lncRNAs and their nearby mRNAs by qPCR. Most of the differentially expressed mRNAs are closely connected with carbohydrate and lipid metabolisms in multiply cancers. Furthermore, part of them were validated in NPC and rhinitis tissues by qPCR. As a result, NR_047538, ENST00000442852, and fatty acid synthase (FASN) were closely associated with NPC. ZBTB7A had a positive association with NR_047538 and negative associations with ENST00000442852 and FASN. The results probably provide novel candidate biomarkers for NPC progression with different levels of ZBTB7A.

LINC00210 as a miR-328-5p sponge promotes nasopharyngeal carcinoma tumorigenesis by activating NOTCH3 pathway

As a kind of essential regulators, long noncoding RNAs (lncRNAs) have attracted a lot of attention in recent years. Nevertheless, the function of lncRNA in nasopharyngeal carcinoma (NPC) remains poorly understood. In the present study, we explained the role and mechanism of LINC00210 in NPC progression. We found that LINC00210 expression was up-regulated in NPC samples. Besides, its overexpression was positively correlated with NPC metastasis while predicting poor prognosis. Based on functional experiments, we revealed that LINC00210 contributed to NPC cell proliferation and invasion in vitro, and promotes tumor growth in vivo. Mechanistically, we identified that LINC00210 was located in the cytoplasm of NPC cells and served as the miR-328-5p sponge. Furthermore, we showed that miR-328-5p targets the 3′ untranslated region (3′-UTR) of NOTCH3. Through inhibiting miR-328-5p activity, LINC00210 promoted NOTCH3 expression in NPC, leading to activation of NOTCH3 signaling pathway. In conclusion, our study indicates LINC00210 promotes NPC progression through modulating proliferation and invasion.

SOX2 recruits KLF4 to regulate nasopharyngeal carcinoma proliferation via PI3K/AKT signaling

SOX2 is a transcription factor that contributes to transcription modification and cancer, but the mechanism by which SOX2 regulates nasopharyngeal carcinoma cell proliferation is not well understood. Here, we identify a SOX2 signaling pathway that facilitates nasopharyngeal carcinoma, where it is upregulated. SOX2 expression was associated with nasopharyngeal carcinoma patient survival. SOX2 knockdown inhibited cell proliferation, colony formation, and tumorigenesis in an subcutaneous mouse xenograft model system. Six hundred and ninety-nine candidate SOX2 downstream dysregulated genes were identified in nasopharyngeal carcinoma cells through cDNA microarray analysis. SOX2 recruited the nuclear transcription factor KLF4 to bind to the PIK3CA promoter upregulate PIK3CA expression, acting to enhance PI3K/AKT signaling and tumorigenesis by upregulating PIK3CA expression. Besides, overexpressing activated AKT or PIK3CA rescued the growth inhibition of cells due to SOX2 knockdown. Together, our study suggest that SOX2 exhibits oncogenic properties and may be a reliable molecular biomarker in nasopharyngeal carcinoma. Targeting SOX2 might be a promising treatment strategy for nasopharyngeal carcinoma treatment.

ANRIL: A lncRNA at the CDKN2A/B Locus With Roles in Cancer and Metabolic Disease

The CDKN2A/B genomic locus is associated with risk of human cancers and metabolic disease. Although the locus contains several important protein-coding genes, studies suggest disease roles for a lesser-known antisense lncRNA encoded at this locus, called ANRIL. ANRIL is a complex gene containing at least 21 exons in simians, with many reported linear and circular isoforms. Like other genes, abundance of ANRIL is regulated by epigenetics, classic transcription regulation, splicing, and post-transcriptional influences such as RNA stability and microRNAs. Known molecular functions of ANRIL include in cis and in trans gene regulation through chromatin modification complexes, and influence over microRNA signaling networks. Polymorphisms at the ANRIL gene are linked to risk for many different cancers, as well as risk of atherosclerotic cardiovascular disease, bone mass, obesity and type 2 diabetes. A broad array of variable reported impacts of polymorphisms on ANRIL abundance, splicing and function suggests that ANRIL has cell-type and context-dependent regulation and actions. In cancer cells, ANRIL gain of function increases proliferation, metastasis, cell survival and epithelial-mesenchymal transformation, whereas ANRIL loss of function decreases tumor size and growth, invasion and metastasis, and increases apoptosis and senescence. In metabolic disease, polymorphisms at the ANRIL gene are linked to risk of type 2 diabetes, coronary artery disease, coronary artery calcium score, myocardial infarction, and stroke. Intriguingly, with the exception of one polymorphism in exon 2 of ANRIL, the single nucleotide polymorphisms (SNPs) associated with atherosclerosis and diabetes are non-overlapping. Evidence suggests that ANRIL gain of function increases atherosclerosis; in diabetes, a risk-SNP reduced the pancreatic beta cell proliferation index. Studies are limited by the uncertain relevance of rodent models to ANRIL studies, since most ANRIL exons do not exist in mouse. Diverse cell-type-dependent results suggest it is necessary to perform studies in the relevant primary human tissue for each disease. Much remains to be learned about the biology of ANRIL in human health and disease; this research area may lead to insight into disease mechanisms and therapeutic approaches.

3D genomic regulation of lncRNA and Xist in X chromosome

Long noncoding RNAs (lncRNAs) act as important regulators in cardiovascular diseases, neural degenerative disease, or cancers, by localizing and spreading across chromatins. lncRNA can regulate the 3D architecture of the enhancer cluster at the target gene locus, relevant to analogous lncRNA-protein coding gene pairs. X inactive specific transcript (Xist) plays a critical role in the process and biological function of lncRNAs. The lncRNA Jpx, Xist activator, is a nonprotein-coding RNA transcribed from a gene within the X-inactivation center and acts as a numerator element to control X-chromosome number and activate Xist transcription by interacting with CCCTC-binding factor. Up-regulated lncRNA Xist initiates X chromosome inactivation process and attracts specific chromatin modifiers. A number of chromatin-modified factors interact with lncRNAs modify 3D genome architecture and mediate Xist function in embryo development. Thus, the regulation of lncRNAs in 3D genome progresses is the key mechanism of Xist, as a therapeutic potential for Xist associated diseases.