ZEB1-AS1: A crucial cancer-related long non-coding RNA

The role of long noncoding RNAs in amyotrophic lateral sclerosis

Amyotrophic lateral sclerosis (ALS) is a progressive neurodegenerative disease with a poor prognosis leading to death. The diagnosis and treatment of ALS are inherently challenging due to its complex pathomechanism. Long noncoding RNAs (lncRNAs) are transcripts longer than 200 nucleotides involved in different cellular processes, incisively gene expression. In recent years, more studies have been conducted on lncRNA classes and interference in different disease pathologies, showing their promising contribution to diagnosing and treating neurodegenerative diseases. In this review, we discussed the role of lncRNAs like NEAT1 and C9orf72-as in ALS pathogenesis mechanisms caused by mutations in different genes, including TAR DNA-binding protein-43 (TDP-43), fused in sarcoma (FUS), superoxide dismutase type 1 (SOD1). NEAT1 is a well-established lncRNA in ALS pathogenesis; hence, we elaborate on its involvement in forming paraspeckles, stress response, inflammatory response, and apoptosis. Furthermore, antisense lncRNAs (as-lncRNAs), a key group of transcripts from the opposite strand of genes, including ZEB1-AS1 and ATXN2-AS, are discussed as newly identified components in the pathology of ALS. Ultimately, we review the current standing of using lncRNAs as biomarkers and therapeutic agents and the future vision of further studies on lncRNA applications.

ZEB1 hypermethylation is associated with better prognosis in patients with colon cancer

BACKGROUND

Colon cancer (CC) is a heterogeneous disease that is categorized into four Consensus Molecular Subtypes (CMS) according to gene expression. Patients with loco-regional CC (stages II/III) lack prognostic factors, making it essential to analyze new molecular markers that can delineate more aggressive tumors. Aberrant methylation of genes that are essential in crucial mechanisms such as epithelial mesenchymal transition (EMT) contributes to tumor progression in CC. We evaluate the presence of hyper- and hypomethylation in subrogate IHC markers used for CMS classification (CDX2, FRMD6, HTR2B, ZEB1) of 144 stage II/III patients and CC cell lines by pyrosequencing. ZEB1 expression was also studied in control and shRNA-silenced CC cell lines and in paired normal tissue/tumors by quantitative PCR. The pattern of ZEB1 staining was also analyzed in methylated/unmethylated tumors by immunohistochemistry.

RESULTS

We describe for the first time the hypermethylation of ZEB1 gene and the hypomethylation of the FRMD6 gene in 32.6% and 50.9% of tumors, respectively. Additionally, we confirm the ZEB1 re-expression by epigenetic drugs in methylated cell lines. ZEB1 hypermethylation was more frequent in CMS1 patients and, more importantly, was a good prognostic factor related to disease-free survival (p = 0.015) and overall survival (p = 0.006) in our patient series, independently of other significant clinical parameters such as patient age, stage, lymph node involvement, and blood vessel and perineural invasion.

CONCLUSIONS

Aberrant methylation is present in the subrogate genes used for CMS classification. Our results are the first evidence that ZEB1 is hypermethylated in CC and that this alteration is an independent factor of good prognosis.

The development and experimental validation of hypoxia-related long noncoding RNAs prognostic signature in predicting prognosis and immunotherapy of cutaneous melanoma

Cutaneous melanoma (CM) is widely acknowledged as a highly aggressive form of malignancy that is associated with a considerable degree of morbidity and poor prognosis. Despite this recognition, the precise role of hypoxia-related long noncoding RNAs (HRLs) in the pathogenesis of CM remains an area of active research. This study sought to elucidate the contribution of HRLs in CM by conducting a thorough screening and extraction of hypoxia-related genes (HRGs). In particular, we conducted univariate and multivariate Cox regression analyses to assess the independence of the prognostic signature of HRLs. Our results demonstrated that a novel risk model could be established based on five prognostic HRLs. Remarkably, patients with low-risk scores exhibited significantly higher overall survival rates compared to their high-risk counterparts, as confirmed by Kaplan-Meier survival analysis. Furthermore, we utilized consensus clustering analysis to categorize CM patients into two distinct subtypes, which revealed marked differences in their prognosis and immune infiltration landscapes. Our nomogram results confirmed that the HRLs prognostic signature served as an independent prognostic indicator, offering an accurate evaluation of the survival probability of CM patients. Notably, our findings from ESTIMATE and ssGSEA analyses highlighted significant disparities in the immune infiltration landscape between low- and high-risk groups of CM patients. Additionally, IPS and TIDE results suggested that CM patients in different risk subtypes may exhibit favorable responses to immunotherapy. Enrichment analysis and GSVA results indicated that immune-related signaling pathways may mediate the role of HRLs in CM. Finally, our tumor mutation burden (TMB) results indicated that patients with low-risk scores had a higher TMB status. In summary, the establishment of a risk model based on HRLs in this study provided an accurate prognostic prediction and correlated with the immune infiltration landscape of CM, thereby providing novel insights for the future clinical management of this disease.

Integrative Analysis Revealed LINC00847 as a Potential Target of Tumor Immunotherapy

Lung cancer is the second most commonly diagnosed cancer and the leading cause of cancer-related death. Lung adenocarcinoma (LUAD) is the most common form of lung cancer and has a low 5-year survival rate. Therefore, much more research is needed to identify cancer biomarkers, promote biomarker-driven therapy and improve treatment outcomes. LncRNAs have been reported to participate in various physiological and pathological processes, especially in cancer, and thus have attracted much attention. In this study, lncRNAs were screened from the single-cell RNA-seq dataset CancerSEA. Among them, four lncRNAs (HCG18, NNT-AS1 and LINC00847 and CYTOR) were closely associated with the prognosis of LUAD patients according to Kaplan-Meier analysis. Further study explored the correlations between these four lncRNAs and immune cell infiltration in cancer. In LUAD, LINC00847 was positively correlated with the immune infiltration of B cells, CD8 T cells, and dendritic cells. LINC00847 decreased the expression of PD-L1, immune checkpoint blockade (ICB) immunotherapy-related gene, which suggests that LINC00847 is a potential new target for tumor immunotherapy.

Mechanistic insights into super-enhancer-driven genes as prognostic signatures in patients with glioblastoma

BACKGROUND

Glioblastoma (GBM) is one of the most common malignant brain tumors in adults and is characterized by high aggressiveness and rapid progression, poor treatment, high recurrence rate, and poor prognosis. Although super-enhancer (SE)-driven genes haven been recognized as prognostic markers for several cancers, whether it can be served as effective prognostic markers for patients with GBM has not been evaluated.

METHODS

We first combined histone modification data with transcriptome data to identify SE-driven genes associated with prognosis in patients with GBM. Second, we developed a SE-driven differentially expressed genes (SEDEGs) risk score prognostic model by univariate Cox analysis, KM survival analysis, multivariate Cox analysis and least absolute shrinkage and selection operator (LASSO) regression. Its reliability in predicting was verified by two external data sets. Third, through mutation analysis, immune infiltration, we explored the molecular mechanisms of prognostic genes. Next, Genomics of Drug Sensitivity in Cancer (GDSC) and the Connectivity Map (cMap) database were employed to assess different sensitivities to chemotherapeutic agents and small-molecule drug candidates between high- and low-risk patients. Finally, SEanalysis database was chosen to identify SE-driven transcription factors (TFs) regulating prognostic markers which will reveal a potential SE-driven transcriptional regulatory network.

RESULTS

First, we developed a 11-gene risk score prognostic model (NCF2, MTHFS, DUSP6, G6PC3, HOXB2, EN2, DLEU1, LBH, ZEB1-AS1, LINC01265, and AGAP2-AS1) selected from 1,154 SEDEGs, which is not only an independent prognostic factor for patients, but also can effectively predict the survival rate of patients. The model can effectively predict 1-, 2- and 3-year survival of patients and was validated in external Chinese Glioma Genome Atlas (CGGA) and Gene Expression Omnibus (GEO) datasets. Second, the risk score was positively correlated with the infiltration of regulatory T cell, CD4 memory activated T cell, activated NK cell, neutrophil, resting mast cell, M0 macrophage, and memory B cell. Third, we found that high-risk patients showed higher sensitivity than low-risk patients to both 27 chemotherapeutic agents and 4 small-molecule drug candidates which might benefit further precision therapy for GBM patients. Finally, 13 potential SE-driven TFs imply how SE regulates GBM patient's prognosis.

CONCLUSION

The SEDEG risk model not only helps to elucidate the impact of SEs on the course of GBM, but also provides a bright future for prognosis determination and choice of treatment for GBM patients.

A cuproptosis-related lncRNA signature to predict prognosis and immune microenvironment of colon adenocarcinoma

Cuproptosis is a novel cell death modality but its regulatory role in the colon cancer remains obscure. This study is committed to establishing a cuproptosis-related lncRNA (CRL) signature to forecast the prognosis for colon adenocarcinoma (COAD). The Cancer Genome Atlas (TCGA) samples were randomly divided into training and validation cohorts. LASSO-COX analysis was performed to construct a prognostic signature consisting of five CRLs (AC015712.2, ZEB1-AS1, SNHG26, AP001619.1, and ZKSCAN2-DT). We found the patients with high-risk scores suffered from poor prognosis in training cohort (p < 0.001) and validation cohort (p = 0.004). Nomogram was created based on the 5-CRL signature. Calibration curves, receiver operating characteristic (ROC) curves, and decision curve analysis (DCA) demonstrated the nomogram performed well in 1‑, 3‑, and 5‑year overall survival (OS). Subsequently, we observed increased infiltration of multiple immune cells and upregulated expression of immune checkpoints and RNA methylation modification genes in high-risk patients. Additionally, gene set enrichment analysis (GSEA) revealed two tumor-related pathways, including MAPK and Wnt signaling pathways. Finally, we found AKT inhibitors, all-trans retinoic acid (ATRA), camptothecin, and thapsigargin had more sensitivity to antitumor therapy in high-risk patients. Collectively, this CRL signature is promising for the prognostic prediction and precise therapy of COAD.

Identification of a novel pathway in sporadic Amyotrophic Lateral Sclerosis mediated by the long non-coding RNA ZEB1-AS1

BACKGROUND

Deregulation of transcription in the pathogenesis of sporadic Amyotrophic Lateral Sclerosis (sALS) is taking central stage with RNA-sequencing analyses from sALS patients tissues highlighting numerous deregulated long non-coding RNAs (lncRNAs). The oncogenic lncRNA ZEB1-AS1 is strongly downregulated in peripheral blood mononuclear cells of sALS patients. In addition, in cancer-derived cell lines, ZEB1-AS1 belongs to a negative feedback loop regulation with hsa-miR-200c, acting as a molecular sponge for this miRNA. The role of the lncRNA ZEB1-AS1 in sALS pathogenesis has not been characterized yet, and its study could help identifying a possible disease-modifying target.

METHODS

the implication of the ZEB1-AS1/ZEB1/hsa-miR-200c/BMI1 pathway was investigated in multiple patients-derived cellular models (patients-derived peripheral blood mononuclear cells and induced pluripotent stem cells-derived neural stem cells) and in the neuroblastoma cell line SH-SY5Y, where its function was inhibited via RNA interference. Molecular techniques such as Real Time PCR, Western Blot and Immunofluorescence were used to assess the pathway dysregulation.

RESULTS

Our results show a dysregulation of a signaling pathway involving ZEB1-AS1/hsa-miR-200c/β-Catenin in peripheral blood mononuclear cells and in induced pluripotent stem cells-derived neural stem cells from sALS patients. These results were validated in vitro on the cell line SH-SY5Y with silenced expression of ZEB1-AS1. Moreover, we found an increase for ZEB1-AS1 during neural differentiation with an aberrant expression of β-Catenin, highlighting also its aggregation and possible impact on neurite length.

CONCLUSIONS

Our results support and describe the role of ZEB1-AS1 pathway in sALS and specifically in neuronal differentiation, suggesting that an impairment of β-Catenin signaling and an alteration of the neuronal phenotype are taking place.

lncRNA-mediated ceRNA network in bladder cancer

Bladder cancer is a common disease associated with high rates of morbidity and mortality. Although immunotherapy approaches such as adoptive T-cell therapy and immune checkpoint blockade have been investigated for the treatment of bladder cancer, their off-target effects and ability to affect only single targets have led to clinical outcomes that are far from satisfactory. Therefore, it is important to identify novel targets that can effectively control tumor growth and metastasis. It is well known that long noncoding RNAs (lncRNAs) are powerful regulators of gene expression. Increasing evidence has shown that dysregulated lncRNAs in bladder cancer are involved in cancer cell proliferation, migration, invasion, apoptosis, and epithelial-mesenchymal transition (EMT). In this review, we focus on the roles and underlying mechanisms of lncRNA-mediated competing endogenous RNA (ceRNA) networks in the regulation of bladder cancer progression. In addition, we discuss the potential of targeting lncRNA-mediated ceRNA networks to overcome cancer treatment resistance and its association with clinicopathological features and outcomes in bladder cancer patients. We hope this review will stimulate research to develop more effective therapeutic approaches for bladder cancer treatment.

Glycosyltransferase-related long non-coding RNA signature predicts the prognosis of colon adenocarcinoma

Purpose

Colon adenocarcinoma (COAD) is the most common type of colorectal cancer (CRC) and is associated with poor prognosis. Emerging evidence has demonstrated that glycosylation by long noncoding RNAs (lncRNAs) was associated with COAD progression. To date, however, the prognostic values of glycosyltransferase (GT)-related lncRNAs in COAD are still largely unknown.

Methods

We obtained the expression matrix of mRNAs and lncRNAs in COAD from The Cancer Genome Atlas (TCGA) database. Then, the univariate Cox regression analysis was conducted to identify 33 prognostic GT-related lncRNAs. Subsequently, LASSO and multivariate Cox regression analysis were performed, and 7 of 33 GT-related lncRNAs were selected to conduct a risk model. Gene set enrichment analysis (GSEA) was used to analyze gene signaling pathway enrichment of the risk model. ImmuCellAI, an online tool for estimating the abundance of immune cells, and correlation analysis were used to explore the tumor-infiltrating immune cells in COAD. Finally, the expression levels of seven lncRNAs were detected in colorectal cancer cell lines by reverse transcription-quantitative polymerase chain reaction (RT-qPCR).

Results

A total of 1,140 GT-related lncRNAs were identified, and 7 COAD-specific GT-related lncRNAs (LINC02381, MIR210HG, AC009237.14, AC105219.1, ZEB1-AS1, AC002310.1, and AC020558.2) were selected to conduct a risk model. Patients were divided into high- and low-risk groups based on the median of risk score. The prognosis of the high-risk group was worse than that of the low-risk group, indicating the good reliability and specificity of our risk model. Additionally, a nomogram based on the risk score and clinical traits was built to help clinical decisions. GSEA showed that the risk model was significantly enriched in metabolism-related pathways. Immune infiltration analysis revealed that five types of immune cells were significantly different between groups, and two types of immune cells were negatively correlated with the risk score. Besides, we found that the expression levels of these seven lncRNAs in tumor cells were significantly higher than those in normal cells, which verified the feasibility of the risk model.

Conclusion

The efficient risk model based on seven GT-related lncRNAs has prognostic potential for COAD, which may be novel biomarkers and therapeutic targets for COAD patients.

[Long noncoding RNA ZEB1-AS1 aggravates cerebral ischemia/reperfusion injury in rats through the HMGB1/TLR-4 signaling axis]

OBJECTIVE

To investigate the role of long non-coding RNA ZEB1-AS1 in cerebral ischemia/reperfusion injury (CI/RI).

METHODS

We detected the temporal changes of ZEB1-AS1 and HMGB1 expression using qPCR and Western blotting in SD rats following CI/RI induced by middle cerebral artery occlusion (MCAO). The rat models of CI/RI were subjected to injections of vectors for ZEB1-AS1 overexpression or knockdown into the lateral ventricle, and the changes in cognitive function, brain water content, blood-brain barrier integrity, and IL-1β and TNF-α levels in the cerebrospinal fluid (CSF) and serum were observed. Neuronal loss and cell apoptosis in the cortex of the rat models were detected by FJC and TUNEL methods, and HMGB1 and TLR-4 expressions were analyzed with Western blotting. We also examined the effects of ZEB1-AS1 knockdown on apoptosis and expressions of HMGB1 and TLR-4 in SH-SY5Y cells with oxygen-glucose deprivation/reoxygenation (OGD/R).

RESULTS

In CI/RI rats, the expressions of ZEB1-AS1 and HMGB1 in the brain tissue increased progressively with the extension of reperfusion time, reaching the peak levels at 24 h followed by a gradual decline. ZEB1-AS1 overexpression significantly aggravated icognitive impairment and increased brain water content, albumin content in the CSF, and IL-1β and TNF-α levels in the CSF and serum in CI/RI rats (P < 0.05), while ZEB1-AS1 knockdown produced the opposite effects (P < 0.05 or 0.01). ZEB1-AS1 overexpression obviously increased the number of FJC-positive neurons in the cortex and enhanced the expressions of HMGB1 and TLR-4 in the rat models (P < 0.01); ZEB1-AS1 knockdown significantly reduced the number of FJC-positive neurons and lowered HMGB1 and TLR-4 expressions (P < 0.01). In SH-SY5Y cells with OGD/R, ZEB1-AS1 knockdown significantly suppressed cell apoptosis and lowered the expressions of HMGB1 and TLR-4 (P < 0.01).

CONCLUSION

ZEB1-AS1 overexpression aggravates CI/RI in rats through the HMGB1/TLR-4 signaling axis.

YY1-induced DLEU1/miR-149-5p Promotes Malignant Biological Behavior of Cholangiocarcinoma through Upregulating YAP1/TEAD2/SOX2

Cholangiocarcinoma is an extremely malignant cancer with poor prognosis. Finding efficient diagnosis and treatment is the indispensable way to improve the prognosis of CCA patients. Therefore, exploring molecular abnormalities in CCA development is urgently needed. DLEU1 is a potential tumor-related lncRNA and abnormally expressed in multiple cancers. In this study, TCGA data analysis showed upregulation of DLEU1 expression in CCA. Furthermore, we confirmed that DLEU1 expression was increased in CCA tissues and cells compared with corresponding controls. Upregulated DLEU1 was related to poor clinicopathological characteristics. Functionally, silencing DLEU1 inhibited CCA proliferation, invasion, stemness maintenance and chemo-resistance, whereas amplifying DLEU1 promoted malignant biological behavior of CCA cells. Mechanistically, DLEU1 expression was transcriptionally facilitated by transcription factor YY1. Moreover, DLEU1 promoted oncogene YAP1 expression by functioning as a sponge to competitively bind to miR-149-5p. YAP1 promoted CCA proliferation, invasion and stemness maintenance, whereas miR-149-5p inhibited malignant biological behavior of CCA. Rescue experiments confirmed that the cancer-promoting effect of DLEU1 was saved by interfering miR-149-5p or YAP1. Furthermore, YAP1 promoted tumor stemness maintenance partly by acting as a transcriptional coactivator to promote TEAD2-induced SOX2 expression. These findings indicated that YY1-induced DLEU1 played a crucial role in CCA progression via miR-149-5p/YAP1/TEAD2/SOX2 axis.

Risk Stratification and Validation of Eleven Autophagy-Related lncRNAs for Esophageal Squamous Cell Carcinoma

Esophageal squamous cell carcinoma (ESCC), the most prevalent subtype of esophageal cancer, ranks sixth in cancer-related mortality, making it one of the deadliest cancers worldwide. The identification of potential risk factors for ESCC might help in implementing precision therapies. Autophagy-related lncRNAs are a group of non-coding RNAs that perform critical functions in the tumor immune microenvironment and therapeutic response. Therefore, we aimed to establish a risk model composed of autophagy-related lncRNAs that can serve as a potential biomarker for ESCC risk stratification. Using the RNA expression profile from 179 patients in the GSE53622 and GSE53624 datasets, we found 11 lncRNAs (AC004690.2, AC092159.3, AC093627.4, AL078604.2, BDNF-AS, HAND2-AS1, LINC00410, LINC00588, PSMD6-AS2, ZEB1-AS1, and LINC02586) that were co-expressed with autophagy genes and were independent prognostic factors in multivariate Cox regression analysis. The risk model was constructed using these autophagy-related lncRNAs, and the area under the receiver operating characteristic curve (AUC) of the risk model was 0.728. To confirm that the model is reliable, the data of 174 patients from The Cancer Genome Atlas (TCGA) esophageal cancer dataset were analyzed as the testing set. A nomogram for ESCC prognosis was developed using the risk model and clinic-pathological characteristics. Immune function annotation and tumor mutational burden of the two risk groups were analyzed and the high-risk group displayed higher sensitivity in chemotherapy and immunotherapy. Expression of differentially expressed lncRNAs were further validated in human normal esophageal cells and esophageal cancer cells. The constructed lncRNA risk model provides a useful tool for stratifying risk and predicting the prognosis of patients with ESCC, and might provide novel targets for ESCC treatment.

Discovery and Validation of a Novel Metastasis-Related lncRNA Prognostic Signature for Colorectal Cancer

Background: Cancer metastasis-related chemoresistance and tumour progression are the leading causes of death among CRC patients. Therefore, it is urgent to identify reliable novel biomarkers for predicting the metastasis of CRC.

Methods: The gene expression and corresponding clinical data of CRC patients were downloaded from The Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO) databases. Univariate and multivariate analyses were performed to identify prognostic metastasis-related lncRNAs. Nomograms were constructed, and the predictive accuracy of the nomogram model was assessed by ROC curve analysis. Then, the R package “pRRophetic” was used to predict chemotherapeutic response in CRC patients. In addition, the CIBERSORT database was introduced to evaluate tumour infiltrating immune cells between the high—and low-risk groups. The potential roles of SNHG7 and ZEB1-AS1 in CRC cell lines were further confirmed by in vitro experiments.

Results: An 8-lncRNA (LINC00261, RP1-170O19.17, CAPN10-AS1, SNHG7, ZEB1-AS1, U47924.27, NIFK-AS1, and LINC00925) signature was constructed for CRC prognosis prediction, which stratified patients into two risk groups. Kaplan-Meier analysis revealed that patients in the higher-risk group had a lower survival probability than those in the lower-risk group [p < 0.001 (TCGA); P = 0.044 (GSE39582); and P = 0.0078 (GSE29621)] The AUCs of 1-, 3-, and 5-year survival were 0.678, 0.669, and 0.72 in TCGA; 0.58, 0.55, and 0.56 in GSE39582; and 0.75, 0.54, and 0.56 in GSE29621, respectively. In addition, the risk score was an independent risk factor for CRC patients. Nomograms were constructed, and the predictive accuracy was assessed by ROC curve analysis. This signature could effectively predict the immune status and chemotherapy response in CRC patients. Moreover, SNHG7 and ZEB1-AS1 depletion significantly suppressed the colony formation, migration, and invasion of CRC cells in vitro.

Conclusion: We constructed a signature that could predict the metastasis of CRC and provide certain theoretical guidance for novel therapeutic approaches for CRC.

A robust immune-related lncRNA signature for the prognosis of human colorectal cancer

Background: Colorectal cancer (CRC) is one of the most prevalent malignant cancers worldwide. Immune-related long non-coding RNAs (IRlncRNAs) are proved to be essential in the development and progression of carcinoma. The purpose of the present study was to develop and validate a prognostic IRlncRNA signature for CRC patients.

Methods: Gene expression profiles of CRC samples were downloaded from The Cancer Genome Atlas (TCGA) database. Immune-related genes were obtained from the ImmPort database and were used to identify IRlncRNA by correlation analysis. Through LASSO Cox regression analyses, a prognostic signature was constructed. Functional enrichment analysis was performed by gene set enrichment analysis (GSEA). TIMER2.0 web server and tumor immune dysfunction and exclusion (TIDE) algorithm were employed to analyze the association between our model and tumor-infiltrating immune cells and immunotherapy response. The expression levels of IRlncRNAs in cell lines were detected by quantitative real-time PCR (qPCR).

Results: A 9-IRlncRNA signature was developed by a LASSO Cox proportional regression model. Based on the signature, CRC patients were divided into high- and low-risk groups with different prognoses. GSEA results indicated that patients in high-risk group were associated with cancer-related pathways. In addition, patients in low-risk group were found to have more infiltration of anti-tumor immune cells and might show a favorable response to immunotherapy. Finally, the result of qPCR revealed that most IRlncRNAs were differently expressed between normal and tumor cell lines.

Conclusion: The constructed 9-IRlncRNA signature has potential to predict the prognosis of CRC patients and may be helpful to guide personalized immunotherapy.

New Insights into LINC00346 and its Role in Disease

Accumulating evidence has shown that long intergenic non-protein-coding RNA 346 (LINC00346) functions as an oncogene in the tumorigenesis of several cancers. The expression level of LINC00346 has been shown to be obviously correlated with prognosis, lymphoma metastasis, histological grade, TNM stage, tumor size and pathologic stage. LINC00346 has been found to regulate specific cellular functions by interacting with several molecules and signaling pathways. In this review, we summarize recent evidence concerning the role of LINC00346 in the occurrence and development of diseases. We also discuss the potential clinical utility of LINC00346, thereby providing new insight into the diagnosis and treatment of diseases. In addition, we further discuss the potential clinical utility of LINC00346 in the diagnosis, prognostication, and treatment of diseases.

LncRNA HCP5 as a potential therapeutic target and prognostic biomarker for various cancers: a meta‑analysis and bioinformatics analysis

BACKGROUND

Accumulating studies indicated that dysregulated long non-coding RNA human histocompatibility leukocyte antigen (HLA) Complex P5 (HCP5) may functions as an potential prognostic predictor in multiple cancers. This meta-analysis was performed to systematically collect studies and conduct an evidence-based evaluation of the prognostic role of HCP5 in malignancies.

METHODS

Four databases (PubMed, Web of Science, Embase and Cochrane library) were comprehensively retrieved from their initiation date to November 9, 2021. Hazard ratio (HR) or odds ratio (OR) with 95% confidence interval (CI) were used to assess the associations between the expression level of HCP5 and prognosis or clinical characteristics. Moreover, results were validated by Gene Expression Profiling Interactive Analysis 2 (GEPIA2) and the National Genomics Data Center (NGDC). Subsequently, the molecular mechanism of HCP5 was predicted based on MEM and StarBase databases. The study protocol was registered at PROSPERO (ID: CRD42021274208).

RESULTS

9 studies, containing 641 patients, were included in this meta-analysis. Our results revealed that HCP5 overexpression was associated with poor overall survival (OS), tumor type, histological differentiation, and lymph node metastasis in most cancers, but was not associated with age, gender and tumor size; down-regulation of HCP5 was associated with worse OS, advanced tumor stage, positive distal metastasis and lymph node metastasis in skin cutaneous melanoma (SKCM). HCP5 was significantly up-regulated in four cancers and down-regulated in SKCM, which was validated by the GEPIA2 cohort. HCP5 expression in various types of cancer was also verified in NGDC. Further functional prediction revealed that HCP5 may participate in some cancer-related pathways.

CONCLUSION

There is a significantly association between dysregulation of HCP5 and both prognosis and clinicopathological features in various cancers. HCP5 may be functions as a novel potential prognostic biomarker and therapeutic target in multiple human cancers.

Development and Validation of a Robust Pyroptosis-Related Signature for Predicting Prognosis and Immune Status in Patients with Colon Cancer

BACKGROUND

Pyroptosis has been confirmed as a type of inflammatory programmed cell death in recent years. However, the prognostic role of pyroptosis in colon cancer (CC) remains unclear.

METHODS

Dataset TCGA-COAD which came from the TCGA portal was taken as the training cohort. GSE17538 from the GEO database was treated as validation cohorts. Differential expression genes (DEGs) between normal and tumor tissues were confirmed. Patients were classified into two subgroups according to the expression characteristics of pyroptosis-related DEGs. The LASSO regression analysis was used to build the best prognostic signature, and its reliability was validated using Kaplan-Meier, ROC, PCA, and t-SNE analyses. And a nomogram based on the multivariate Cox analysis was developed. The enrichment analysis was performed in the GO and KEGG to investigate the potential mechanism. In addition, we explored the difference in the abundance of infiltrating immune cells and immune microenvironment between high- and low-risk groups. And we also predicted the association of common immune checkpoints with risk scores. Finally, we verified the expression of the pyroptosis-related hub gene at the protein level by immunohistochemistry.

RESULTS

A total of 23 pyroptosis-related DEGs were identified in the TCGA cohort. Patients were classified into two molecular clusters (MC) based on DEGs. Kaplan-Meier survival analysis indicated that patients with MC1 represented significantly poorer OS than patients with MC2. 13 overall survival- (OS-) related DEGs in MCs were used to construct the prognostic signature. Patients in the high-risk group exhibited poorer OS compared to those in the low-risk group. Combined with the clinical features, the risk score was found to be an independent prognostic factor of CC patients. The above results are verified in the external dataset GSE17538. A nomogram was established and showed excellent performance. Gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses indicated that the varied prognostic performance between high- and low-risk groups may be related to the immune response mediated by local inflammation. Further analysis showed that the high-risk group has stronger immune cell infiltration and lower tumor purity than the low-risk group. Through the correlation between risk score and immune checkpoint expression, T-cell immunoglobulin and mucin domain-containing protein 3 (TIM-3) was predicted as a potential therapeutic target for the high-risk group.

CONCLUSION

The 13-gene signature was associated with OS, immune cells, tumor purity, and immune checkpoints in CC patients, and it could provide the basis for immunotherapy and predicting prognosis and help clinicians make decisions for individualized treatment.

LncRNA ZEB1-AS1 knockdown alleviates oxidative low-density lipoprotein-induced endothelial cell injury via the miR-590-5p/HDAC9 axis

Oxidative low-density lipoprotein (ox-LDL) is thought to induce vascular endothelial cell injury, which contributes to the aetiopathogenesis of atherosclerosis (AS). Several previous reports have identified that lncRNA ZEB1-AS1 participates in the regulatory mechanisms of endothelial cell injury, but the potential interaction mechanism between ZEB1-AS1 and miR-590-5p in ox-LDL-induced endothelial cell damage is not clear. ZEB1-AS1 and miR-590-5p expression were tested by quantitative real-time polymerase chain reaction (qRT-PCR) in ox-LDL-treated endothelial cells. The proliferation and apoptosis were determined by MTT and Annexin V/PI double-staining assay, respectively. The protein expression of HDAC9, tumor necrosis factor α (TNF-α), cleaved caspase-3, and cleaved PARP were measured by western blot analysis. Dual-luciferase reporter and RIP assays affirmed the functional targets of ZEB1-AS1. ZEB1-AS1 expression was upregulated in ox-LDL-treated HUVECs, and miR-590-5p was lessened in a dose- or time-depended manner, respectively. Knockdown of ZEB1-AS1 facilitated ox-LDL-treated endothelial cell proliferation and inhibited cell apoptosis. Moreover, miR-590-5p was directly targeted via ZEB1-AS1 in ox-LDL-treated HUVECs. ZEB1-AS1 silencing attenuated ox-LDL-induced cell injury via regulation of miR-590-5p expression. Furthermore, HDAC9 reversed the influence of miR-590-5p on propagation and apoptosis of ox-LDL-induced endothelial cells. Knockdown of ZEB1-AS1 alleviates ox-LDL-induced endothelial cell injury by regulating the miR-590-5p/HDAC9 axis.

A novel prognostic cancer-related lncRNA signature in papillary renal cell carcinoma

Background

Papillary renal cell carcinoma (pRCC) ranks second in renal cell carcinoma and the prognosis of pRCC remains poor. Here, we aimed to screen and identify a novel prognostic cancer-related lncRNA signature in pRCC.

Methods

The RNA-seq profile and clinical feature of pRCC cases were downloaded from TCGA database. Significant cancer-related lncRNAs were obtained from the Immlnc database. Differentially expressed cancer-related lncRNAs (DECRLs) in pRCC were screened for further analysis. Cox regression report was implemented to identify prognostic cancer-related lncRNAs and establish a prognostic risk model, and ROC curve analysis was used to evaluate its precision. The correlation between RP11-63A11.1 and clinical characteristics was further analyzed. Finally, the expression level and role of RP11-63A11.1 were studied in vitro.

Results

A total of 367 DECRLs were finally screened and 26 prognostic cancer-related lncRNAs were identified. Among them, ten lncRNAs (RP11-573D15.8, LINC01317, RNF144A-AS1, TFAP2A-AS1, LINC00702, GAS6-AS1, RP11-400K9.4, LUCAT1, RP11-63A11.1, and RP11-156L14.1) were independently associated with prognosis of pRCC. These ten lncRNAs were incorporated into a prognostic risk model. In accordance with the median value of the riskscore, pRCC cases were separated into high and low risk groups. Survival analysis indicated that there was a significant difference on overall survival (OS) rate between the two groups. The area under curve (AUC) in different years indicated that the model was of high efficiency in prognosis prediction. RP11-63A11.1 was mainly expressed in renal tissues and it correlated with the tumor stage, T, M, N classifications, OS, PFS, and DSS of pRCC patients. Consistent with the expression in pRCC tissue samples, RP11-63A11.1 was also down-regulated in pRCC cells. More importantly, up-regulation of RP11-63A11.1 attenuated cell survival and induced apoptosis.

Conclusions

Ten cancer-related lncRNAs were incorporated into a powerful model for prognosis evaluation. RP11-63A11.1 functioned as a cancer suppressor in pRCC and it might be a potential therapeutic target for treating pRCC.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12935-021-02247-6.

Identification and Roles of miR-29b-1-3p and miR29a-3p-Regulated and Non-Regulated lncRNAs in Endocrine-Sensitive and Resistant Breast Cancer Cells

Despite improvements in the treatment of endocrine-resistant metastatic disease using combination therapies in patients with estrogen receptor α (ERα) primary tumors, the mechanisms underlying endocrine resistance remain to be elucidated. Non-coding RNAs (ncRNAs), including microRNAs (miRNA) and long non-coding RNAs (lncRNA), are targets and regulators of cell signaling pathways and their exosomal transport may contribute to metastasis. Previous studies have shown that a low expression of miR-29a-3p and miR-29b-3p is associated with lower overall breast cancer survival before 150 mos. Transient, modest overexpression of miR-29b1-3p or miR-29a-3p inhibited MCF-7 tamoxifen-sensitive and LCC9 tamoxifen-resistant cell proliferation. Here, we identify miR-29b-1/a-regulated and non-regulated differentially expressed lncRNAs in MCF-7 and LCC9 cells using next-generation RNA seq. More lncRNAs were miR-29b-1/a-regulated in LCC9 cells than in MCF-7 cells, including DANCR, GAS5, DSCAM-AS1, SNHG5, and CRND. We examined the roles of miR-29-regulated and differentially expressed lncRNAs in endocrine-resistant breast cancer, including putative and proven targets and expression patterns in survival analysis using the KM Plotter and TCGA databases. This study provides new insights into lncRNAs in endocrine-resistant breast cancer.

Construction of a novel mRNA-miRNA-lncRNA network and identification of potential regulatory axis associated with prognosis in colorectal cancer liver metastases

Liver metastasis is a leading cause of death in patients with colorectal cancer (CRC). Increasing evidence demonstrates that competing endogenous RNA (ceRNA) networks play important roles in malignant cancers. The purpose of this study was to identify molecular markers and build a ceRNA network as a significant predictor of colorectal liver metastases (CRLM). By integrated bioinformatics analysis, we found that apolipoprotein C1 (APOC1) was upregulated in CRLM and associated with prognosis in patients with CRC and thereby established an APOC1-dependent ceRNA network. By survival analysis, expression analysis, and correlation analysis of each element in the ceRNA network, we identified that ZEB1-AS1, miR-335-5p and APOC1 regulated each other. We further experimentally confirmed that ZEB1-AS1 promoted a CRC progression via regulating the expression of miR-335-5p that controlled the expression of APOC1. Our findings indicate that the ZEB1-AS1-miR-335-5p-APOC1 ceRNA regulatory network is significantly valuable for better prognosis of patients with CRC and as a new therapeutic target for the treatment of CRLM.

LncRNA ZEB1-AS1 regulates hepatocellular carcinoma progression by targeting miR-23c

BACKGROUND

It has been reported that long-chain non-coding RNA (lncRNA) zinc finger E-box binding homeobox 1 antisense 1 (ZEB1-AS1) is an oncogene in various cancers, including hepatocellular carcinoma (HCC). We investigated the role and mechanism of ZEB1-AS1 as a competitive endogenous RNA (ceRNA) combined with miR-23c in HCC cell proliferation and invasion.

METHODS

QRT-PCR was used to detect ZEB1-AS1 and miR-23c expressions in HCC tissues and cells. The dual luciferase reporter assay detected the targeted regulation of miR-23c and ZEB1-AS1. We also performed the correlation analysis of their expression in HCC tissues by the Spearman's correlation analysis. 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay was used to detect the proliferation of hepatoma cells. Cell invasion was assessed by the Transwell assay.

RESULTS

QRT-PCR results indicated ZEB1-AS1 was upregulated and miR-23c was downregulated in HCC tissues and cell lines. ZEB1-AS1 knockdown hampered the proliferation and invasion of HCC cells. Dual luciferase reporter assay showed that miR-23c is a target of ZEB1-AS1, and ZEB1-AS1 was significantly negatively correlated with the miR-23c expression in HCC tissues. The results of MTT and Transwell assay showed that miR-23c inhibition restored the inhibitory effect of ZEB1-AS1 knockdown on HCC cells proliferation and invasion.

CONCLUSIONS

As a ceRNA, lncRNA ZEB1-AS1 may play a vital role in inhibiting HCC progression through miR-23c, which will provide new clues and theoretical basis for the HCC diagnosis and treatment.

Identification of lncRNAs associated with the pathogenesis of ankylosing spondylitis

Background

Ankylosing spondylitis (AS) is a chronic autoimmune disease affecting the sacroiliac joint. To date, few studies have examined the association between long non-coding RNAs (lncRNAs) and AS pathogenesis. As such, we herein sought to characterize patterns of AS-related lncRNA expression and to evaluate the potential role played by these lncRNAs in this complex autoimmune context.

Methods

We conducted a RNA-seq analysis of peripheral blood mononuclear cell (PBMC) samples isolated from five AS patients and corresponding controls. These data were then leveraged to characterize AS-related lncRNA expression patterns. We further conducted GO and KEGG enrichment analyses of the parental genes encoding these lncRNAs, and we confirmed the validity of our RNA-seq data by assessing the expression of six lncRNAs via qRT-PCR in 15 AS and control patient samples. Pearson correlation analyses were additionally employed to examine the associations between the expression levels of these six lncRNAs and patient clinical index values.

Results

We detected 56,575 total lncRNAs in AS and control patient samples during our initial RNA-seq analysis, of which 200 and 70 were found to be up- and down-regulated (FC > 2 or < 0.05; P < 0.05), respectively, in AS samples relative to controls. In qRT-PCR validation assays, we confirmed the significant upregulation of NONHSAT118801.2, ENST00000444046, and NONHSAT183847.1 and the significant downregulation of NONHSAT205110.1, NONHSAT105444.2, and NONHSAT051856.2 in AS patient samples. We further found the expression of NONHSAT118801.2 and NONHSAT183847.1 to be positively correlated with disease severity.

Conclusion

Overall, our findings highlight several lncRNAs that are specifically expressed in PBMCs of AS patients, indicating that they may play key functions in the pathogenesis of this autoimmune disease. Specifically, we determined that NONHSAT118801.2 and NONHSAT183847.1 may influence the occurrence and development of AS.

Comprehensive Review on the Clinical Relevance of Long Non-Coding RNAs in Cutaneous Melanoma

Cutaneous melanoma is considered a rare tumor, although it is one of the most common cancers in young adults and its incidence has risen in the last decades. Targeted therapy, with BRAF and MEK inhibitors, and immunotherapy revolutionized the treatment of metastatic melanoma but there is still a considerable percentage of patients with primary or acquired resistance to these therapies. Recently, oncology researchers directed their attention at the role of long non-coding RNAs (lncRNAs) in different types of cancers, including melanoma. lncRNAs are RNA transcripts, initially considered "junk sequences", that have been proven to have a crucial role in the fine regulation of physiological and pathological processes of different tissues. Furthermore, they are more expressed in tumors than protein-coding genes, constituting perfect candidates either as biomarkers (diagnostic, prognostic, predictive) or as therapeutic targets. In this work, we reviewed all the literature available for lncRNA in melanoma, elucidating all the potential roles in this tumor.

lncRNA TTN-AS1 facilitates proliferation, invasion, and epithelial-mesenchymal transition of breast cancer cells by regulating miR-139-5p/ZEB1 axis

Breast cancer is a common malignant tumor suffered predominantly by women worldwide, which results in serious levels of morbidity and mortality. To control the effects of the cancer, it is critically important to elucidate the pathophysiological processes by which it occurs and develops. Reports have demonstrated that long noncoding RNAs perform a critical role in the development and metastasis of cancers. The lncRNA TTN-AS1 is considered carcinogenic. Nevertheless, the importance and biological functions of TTN-AS1 in breast cancer require greater exploration. In the current paper, we observed that TTN-AS1 expression was significantly upregulated in breast cancer tissues/cells compared with those that are healthy. TTN-AS1 enhanced the proliferation, migration, invasion, and epithelial-mesenchymal transformation of breast cancer cells. Furthermore, a direct target of TTN-AS1, miR-139-5p was negatively regulated. In addition, zinc finger E-box binding homeobox 1 (ZEB1) is an important nuclear transcription factor, the expression of which is increased in multiple tumors. Here, we also found that ZEB1 is a target of miR-139-5p, of which TTN-AS1 could regulate the expression through competition with miR-139-5p. That is, TTN-AS1 promoted proliferation and invasion of breast cancer cells by interaction with the miR-139-5p/ZEB1 axis. In conclusion, the present study aimed to illustrate the significance of TTN-AS1 in breast cancer metastasis and contribute to potentially innovative strategies for its treatment.

An Autophagy-Related Long Noncoding RNA Signature Contributes to Poor Prognosis in Colorectal Cancer

Purpose

Colorectal cancer is one of the most common malignant primary tumors, prone to metastasis, and associated with a poor prognosis. As autophagy is closely related to the development and treatment of colorectal cancer, we investigated the potential prognostic value of long noncoding RNA (lncRNA) associated with autophagy in colorectal cancer.

Methods

In this study, we acquired information on the expression of lncRNAs in colorectal cancer from the Cancer Genome Atlas (TCGA) database and found that 860 lncRNAs were associated with autophagy-related genes. Subsequently, univariate Cox regression analysis was used to investigate 32 autophagy-related lncRNAs linked to colon cancer prognosis. Subsequently, eight of the 32 autophagy-related lncRNAs (i.e., long intergenic nonprotein coding RNA 1503 [LINC01503], ZEB1 antisense RNA 1 [ZEB1-AS1], AC087481.3, AC008760.1, AC073896.3, AL138756.1, AL022323.1, and TNFRSF10A-AS1) were selected through multivariate Cox regression analysis. Based on these autophagy-related lncRNAs, a risk signature was constructed, and the patients were divided into high- and low-risk groups.

Results

The high-risk group's overall survival time was significantly shorter than that of the low-risk group (p < 0.0001). Receiver operating characteristic curve analysis was performed to further confirm the validity of the model (area under the curve: 0.689). Moreover, multivariate regression suggested that the risk score was a significant prognostic risk factor in colorectal cancer. Gene set enrichment analysis showed that these gene sets are significantly enriched in cancer-related pathways, such as Kirsten rat sarcoma viral oncogene homolog (KRAS) signaling.

Conclusion

The risk signature of eight autophagy-related lncRNAs has prognostic potential for colorectal cancer. These autophagy-related lncRNAs may play a vital role in the biology of colorectal cancer.

The fibrotic microenvironment promotes the metastatic seeding of tumor cells into the lungs via mediating the ZEB1-AS1/miR-200b-3p/ZEB1 signaling

Fibrotic microenvironment has been reported to have a pro-metastasis effect on tumor cells, but the mechanism remains unclear. The current study aimed to explore the underlying mechanism by which the fibrotic microenvironment affects tumor cells. A tumor metastasis model was established by injecting tumor cells containing GFP into mice with pulmonary fibrosis. Lung tissues and fibroblasts were harvested, and conditioned medium (CM) were collected from fibrotic lungs and fibroblasts. Hematoxylin & eosin staining and immunohistochemistry were used to detect pulmonary metastasis and FSP1 expression, respectively. Bioinformatics and dual-luciferase reporter assay proved that the target genes of ZEB1-AS1 and miR-200b-3p were miR-200b-3p and ZEB1, respectively. Quantitative real-time polymerase chain reaction (qRT-PCR) was performed to detect the expressions of GFP, ZEB1-AS1, and miR-200b-3p. Transwell assay, Annexin V/PI assay, and colorimetry were performed to examine the effects of CM, ZEB1-AS1, miR-200b-3p, and ZEB1 on cell invasion, apoptosis, and the activity level of caspase-3/-9. Pulmonary metastasis was promoted and the expressions of FSP1 and GFP were increased in mice with pulmonary fibrosis. CM enhanced the invasion and inhibited the apoptosis of tumor cells. SiZEB1-AS1 and siZEB1 inhibited the invasion and apoptosis of tumor cells, while miR-200b-3p inhibitor had the opposite effect of SiZEB1-AS1 and siZEB1, and further reversed the effect of siZEB1 on tumor cell invasion and apoptosis. SiZEB1-AS1 reversed the effects of both miR-200b-3p inhibitor and miR-200b-3p inhibitor+siZEB1 on tumor cell invasion and apoptosis. Fibrotic microenvironment promoted the metastatic seeding of tumor cells into the lungs via mediating the ZEB1-AS1/miR-200b-3p/ZEB1 signaling.

The Role of Non-coding RNAs in Viral Myocarditis

Viral myocarditis (VMC) is a disease characterized as myocardial parenchyma or interstitium inflammation caused by virus infection, especially Coxsackievirus B3 (CVB3) infection, which has no accurate non-invasive examination for diagnosis and specific drugs for treatment. The mechanism of CVB3-induced VMC may be related to direct myocardial damage of virus infection and extensive damage of abnormal immune response after infection. Non-coding RNA (ncRNA) refers to RNA that is not translated into protein and plays a vital role in many biological processes. There is expanding evidence to reveal that ncRNAs regulate the occurrence and development of VMC, which may provide new treatment or diagnosis targets. In this review, we mainly demonstrate an overview of the potential role of ncRNAs in the pathogenesis, diagnosis and treatment of CVB3-induced VMC.

LncZEB1-AS1 regulates hepatocellular carcinoma bone metastasis via regulation of the miR-302b-EGFR-PI3K-AKT axis

In patients with hepatocellular carcinoma (HCC), disease progression and associated bone metastasis (BM) can markedly reduce quality of life. While the long non-coding RNA (lncRNA) zinc finger E-box binding homeobox 1 antisense 1 (ZEB1-AS1) has been shown to function as a key regulator of oncogenic processes in HCC and other tumor types, whether it plays a role in controlling HCC BM remains to be established. In the current study, we detected the significant upregulation of lncZEB1-AS1 in HCC tissues, and we found this expression to be associated with BM progression. When we knocked down this lncRNA in HCC cells, we found that this significantly reduced their migratory, invasive, and metastatic activity both in vitro and in vivo. At a mechanistic level, we found that lncZEB1-AS1 was able to target miR-302b and to thereby increase PI3K-AKT pathway activation and EGFR expression, resulting in the enhanced expression of downstream matrix metalloproteinase genes in HCC cells. In summary, our results provide novel evidence that lncZEB1-AS1 can promote HCC BM through a mechanism dependent upon the activation of PI3K-AKT signaling, thus highlighting a potentially novel therapeutic avenue for the treatment of such metastatic progression in HCC patients.

Screening of a Novel Upregulated lncRNA, A2M-AS1, That Promotes Invasion and Migration and Signifies Poor Prognosis in Breast Cancer

Understanding of prognostic factors and therapeutic targets for breast cancer is imperative for guidance of patient care. We studied 1203 tumour samples from the Gene Expression Omnibus (GEO) to evaluate potential genes related to breast cancer. R software was used to analyse differentially expressed long noncoding RNAs (lncRNAs) in the RNA microarray expression profiles GSE45827 and GSE65216 and to identify a series of differentially expressed lncRNAs associated with human breast cancer. Of these lncRNAs, A2M-AS1, a lncRNA that has not been previously reported, was significantly upregulated in human breast cancer tissues compared with adjacent nontumour tissues. Importantly, A2M-AS1 upregulation was significantly associated with ER-negative, HER2-positive, and basal-like breast cancer and with poor recurrence-free survival and metastasis-free survival in breast cancer patients. After validating these results in 96 collected human breast cancer tissues and 64 paired adjacent noncancerous tissues, we further investigated the roles of A2M-AS1 in human ER-negative and basal-like breast cancer cells. The results revealed that A2M-AS1 significantly promotes human breast cancer cell proliferation, invasion, and migration. Additionally, bioinformatics analysis of genes coexpressed with A2M-AS1 in the context of human breast cancer combined with qRT-PCR and Western blot assays revealed that A2M-AS1 exerts regulatory effects on downstream factors in the cell adhesion molecule pathway, including CD2 and SELL. These results imply that A2M-AS1 might be a promising candidate prognostic factor and therapeutic target for breast cancer.

Long non‑coding RNA ZEB1‑AS1 predicts a poor prognosis and promotes cancer progression through the miR‑200a/ZEB1 signaling pathway in intrahepatic cholangiocarcinoma

Emerging evidence suggests that long non‑coding RNAs (lncRNAs) play pivotal roles in cancer progression, including in intrahepatic cholangiocarcinoma (IHCC). The overexpression of lncRNA ZEB1 antisense 1 (ZEB1‑AS1) has been discovered in several types of cancer; however, the clinical significance and functional role of ZEB1‑AS1 in IHCC have not yet been determined. In the present study, ZEB1‑AS1 was found to be upregulated in IHCC cell lines and tissues. A high ZEB1‑AS1 expression was associated with clinical progression and a poor survival of patients with IHCC, and was identified as an independent risk factor for a poor prognosis. In addition, ZEB1‑AS1 promoted the proliferation and metastasis of IHCC cells both in vitro and in vivo. ZEB1‑AS1 was demonstrated to increase the expression of ZEB1 by sponging miR‑200a and to thereby accelerate epithelial‑mesenchymal transition (EMT). On the whole, the findings of the present study demonstrate that ZEB1‑AS1 promotes proliferation and metastasis in IHCC, and induces EMT through the miR‑200a/ZEB1 signaling pathway. ZEB1‑AS1 may thus be a promising prognostic biomarker and essential therapeutic target for IHCC.

lncRNA ZFAS1 Is Involved in the Proliferation, Invasion and Metastasis of Prostate Cancer Cells Through Competitively Binding to miR-135a-5p

Background

Prostate cancer (PCa) is a common malignant tumor in men. lncRNA ZFAS1 plays a carcinogenic role in many types of cancer; however, its potential role in PCa remains unclear. The current study aimed to determine the expression and function of ZFAS1 in PC.

Methods

The ZFAS1 expression in PC tissues and cells was determined by quantitative polymerase chain reaction (qPCR). SiZFAS1, miR-135a-5p mimic and miR-135a-5p inhibitor were transfected into PCa cells. The direct target of ZFAS1 was predicted by Starbase and verified by dual-luciferase reporter. Cell viability, proliferation, apoptosis, migration and invasion of the PCa cells were determined by cell counting kit-8, clone formation assay, flow cytometer, scratch and Transwell assay, respectively. The expression levels of related proteins and mRNAs were determined by Western blotting and qPCR.

Results

ZFAS1 expression was up-regulated in PCa cells and tissues. ZFAS1 could competitively bind to miR-135a-5p in PCa cells, and down-regulation of ZFAS1 inhibited cell viability, proliferation, migration, invasion of PCa cells and the occurrence of epithelial-mesenchymal transformation (EMT) and promoted apoptosis of PCa cells and increased the miR-135a-5p expression. Moreover, the function of miR-135a-5p mimic in PCa cells was consistent with ZFAS1 knockdown, while the function of miR-135a-5p inhibitor was opposite to that of miR-135a-5p mimic in PCa cells. The results showed that knocking down ZFAS1 could attenuate the effects of miR-135a-5p inhibitor on cell proliferation, invasion and EMT of PCa cells.

Conclusion

Knocking down ZFAS1 could inhibit the proliferation, invasion and metastasis of PCa cells through regulating miR-135a-5p expression.

AR-induced ZEB1-AS1 represents poor prognosis in cholangiocarcinoma and facilitates tumor stemness, proliferation and invasion through mediating miR-133b/HOXB8

Zinc finger E-box binding homeobox 1 antisense 1 (ZEB1-AS1) has displayed vital regulatory function in various tumors. However, the biological function of ZEB1-AS1 in cholangiocarcinoma (CCA) remains unclear. In this study, we confirmed that ZEB1-AS1 expression was increased in CCA tissues and cells, respectively. Upregulated ZEB1-AS1 was related to lymph node invasion, advanced TNM stage and poor survival of CCA patients. ZEB1-AS1 exhibited high sensitivity and specificity to be an independent poor prognostic factor of patients with CCA. Functionally, knocking down ZEB1-AS1 attenuated tumor cell stemness, restrained cellular viability in vitro and in vivo, and inhibited CCA cell migration and invasion by reversing epithelial-mesenchymal transition. For the mechanism, androgen receptor (AR) directly promoted ZEB1-AS1 expression, and further ZEB1-AS1 increased oncogene homeobox B8 (HOXB8) by sponging miR-133b. In addition, malignant phenotypes of CCA promoted by ZEB1-AS1 dysregulation were rescued separately through interfering miR-133b and HOXB8, suggesting AR/ZEB1-AS1/miR-133b/HOXB8 exerted crucial functions in tumorigenesis and progression of CCA.

lncRNA ZEB1-AS1 inhibits high glucose-induced EMT and fibrogenesis by regulating the miR-216a-5p/BMP7 axis in diabetic nephropathy

Diabetic nephropathy (DN) is one of the leading causes of mortality in diabetic patients. Long non-coding RNA zinc finger E-box binding homeobox 1 antisense 1 (ZEB1-AS1) plays a crucial role in the development of various diseases, including DN. However, the molecular mechanism of ZEB1-AS1 in DN pathogenesis remains elusive. An in vitro DN model was established by treating HK-2 cells with high glucose (HG). Quantitative polymerase chain reaction (qRT-PCR) was utilized to detect the expression levels of ZEB1-AS1, microRNA-216a-5p (miR-216a-5p), and bone morphogenetic protein 7 (BMP7). Western blot assay was used to evaluate the protein levels of BMP7, epithelial-to-mesenchymal transition (EMT)-related proteins, and fibrosis markers. Additionally, the interaction among ZEB1-AS1, miR-216a-5p, and BMP7 was predicted by MiRcode (http://www.mircode.org) and starBase 2.0 (omics_06102, omicX), and confirmed by luciferase reporter assay. ZEB1-AS1 and BMP7 were down-regulated, while miR-216a-5p was highly expressed in kidney tissues of DN patients. Consistently, HG treatment decreased the levels of ZEB1-AS1 and BMP7, whereas HG increased miR-216a-5p expression in HK-2 cells in a time-dependent manner. ZEB1-AS1 upregulation inhibited HG-induced EMT and fibrogenesis. Furthermore, ZEB1-AS1 directly targeted miR-216a-5p, and overexpression of miR-216a-5p restored the inhibitory effects of ZEB1-AS1 overexpression on EMT and fibrogenesis. BMP7 was negatively targeted by miR-216a-5p. In addition, ZEB1-AS1 suppressed HG-induced EMT and fibrogenesis by regulating miR-216a-5p and BMP-7. lncRNA ZEB1-AS1 inhibited high glucose-induced EMT and fibrogenesis via regulating miR-216a-5p/BMP7 axis in diabetic nephropathy, providing a potential target for DN therapy.

Long non-coding RNA ZEB1-AS1 promotes colon adenocarcinoma malignant progression via miR-455-3p/PAK2 axis

Objective

The long non‐coding RNA zinc finger E‐box‐binding homeobox 1 antisense 1 (ZEB1‐AS1) acts as an oncogenic regulator in many human tumours. In the present study, we identify the role and potential molecular biological mechanisms of ZEB1‐AS1 in colon adenocarcinoma (COAD).

Methods

QRT‐PCR was used to detect the expression of ZEB1‐AS1, miR‐455‐3p and p21‐activated kinases 2 (PAK2) in COAD tissues. CCK8 assay, EdU assay, transwell assay and scratch wound assay were used to explore the biological function of ZEB1‐AS1 in COAD cells. Bioinformatics, luciferase reporter assays and an RNA pull‐down assay were used to demonstrate the mechanism of ZEB1‐AS1. We further explore the role of ZEB1‐AS1 in vivo though xenograft tumour assay.

Results

We found that ZEB1‐AS1 expression was significantly up‐regulated in COAD tissues, and high ZEB1‐AS1 level was correlated with the poor prognosis of COAD patients. MiR‐455‐3p plays an anti‐cancer role in COAD by targeting PAK2. We confirmed that ZEB1‐AS1 promotes PAK2 expression by sponging miR‐455‐3p, thus facilitating COAD cell growth and metastasis.

Conclusions

To sum up, this result illustrates the novel molecular mechanism of ZEB1‐AS1 in COAD and provides a new target for the diagnosis and treatment of COAD patients.

DGCR8/ZFAT-AS1 Promotes CDX2 Transcription in a PRC2 Complex-Dependent Manner to Facilitate the Malignant Biological Behavior of Glioma Cells

Studies have found that RNA-binding proteins (RBPs) and long non-coding RNAs (lncRNAs) are dysregulated and play an important regulatory role in the development of tumors. Based on The Cancer Genome Atlas (TCGA) database, our findings from experiments, and the evidence of previous studies, we screened DiGeorge syndrome critical region gene 8 (DGCR8), ZFAT antisense RNA 1 (ZFAT-AS1), and caudal type homeobox 2 (CDX2) as research candidates. In the present study, DGCR8 and CDX2 were highly expressed and ZFAT-AS1 was markedly downregulated in glioma tissues and cells. DGCR8 or CDX2 knockdown or ZFAT-AS1 overexpression suppressed glioma cell proliferation, migration, and invasion and facilitated apoptosis. DGCR8 might decrease ZFAT-AS1 expression by attenuating its stability in a manner of inducing its cleavage. Importantly, ZFAT-AS1 could inhibit CDX2 transcription by mediating the methylation of histone H3 on lysine 27 (H3K27me3) modification induced by PRC2 in the CDX2 promoter region. In addition, CDX2 transcriptionally activated DGCR8 expression by binding to its promoter regions, forming a positive feedback loop of DGCR8/ZFAT-AS1/CDX2. In conclusion, DGCR8/ZFAT-AS1 promotes CDX2 transcription in a PRC2 complex-dependent manner to facilitate the malignant biological behavior of glioma cells.

LncRNAs act as prognostic biomarkers in bladder carcinoma: A meta-analysis

Background and purpose

Increasing studies have shown that different kinds of lncRNAs play key role in the development of multiple carcinomas. Therefore, we conducted a meta-analysis to investigate an association between the expression level of lncRNAs and the prognosis of bladder cancer (death or other clinical outcomes).

Methods

A systematic literature search was performed by using PubMed. Twenty-four studies were included in the meta-analysis based on the inclusion and exclusion criteria. In total, there are 1652 independent participants.

Results

The result showed that high expression levels of lncRNAs were demonstrated to be associated with poor overall survival (OS) (HR = 2.33, 95%CI: 1.51–2.39, p < 0.01) in bladder carcinoma, but there was no significant correlation between lncRNAs level and recurrence-free survival (RFS) (pooled HR = 1.57, 95%CI 0.69–3.56, p = 0.284), and progression-free survival (PFS) (pooled HR = 1.37, 95%CI 0.79–2.38, p = 0.269). Additionally, increased lncRNAs expression was found to be moderately correlated with tumor stage and progression (II/III/IV vs. I, OR = 3.20, 95%CI: 1.72–5.98, p < 0.001). In addition, elevated lncRNAs expression predicted lymph node metastasis (LNM) significantly (pooled OR = 2.29, 95 % CI 1.33–3.95, p < 0.01). No significant heterogeneity was observed among studies except lymph node metastasis.

Conclusion

In conclusion, high expression levels of lncRNAs were demonstrated to be associated with poor OS and positive LNM, and lncRNAs might be potential prognostic markers in bladder cancer.

Whole transcriptome analysis reveals correlation of long noncoding RNA ZEB1-AS1 with invasive profile in melanoma

Melanoma is the deadliest form of skin cancer, and little is known about the impact of deregulated expression of long noncoding RNAs (lncRNAs) in the progression of this cancer. In this study, we explored RNA-Seq data to search for lncRNAs associated with melanoma progression. We found distinct lncRNA gene expression patterns across melanocytes, primary and metastatic melanoma cells. Also, we observed upregulation of the lncRNA ZEB1-AS1 (ZEB1 antisense RNA 1) in melanoma cell lines. Data analysis from The Cancer Genome Atlas (TCGA) confirmed higher ZEB1-AS1 expression in metastatic melanoma and its association with hotspot mutations in BRAF (B-Raf proto-oncogene, serine/threonine kinase) gene and RAS family genes. In addition, a positive correlation between ZEB1-AS1 and ZEB1 (zinc finger E-box binding homeobox 1) gene expression was verified in primary and metastatic melanomas. Using gene expression signatures indicative of invasive or proliferative phenotypes, we found an association between ZEB1-AS1 upregulation and a transcriptional profile for invasiveness. Enrichment analysis of correlated genes demonstrated cancer genes and pathways associated with ZEB1-AS1. We suggest that the lncRNA ZEB1-AS1 could function by activating ZEB1 gene expression, thereby influencing invasiveness and phenotype switching in melanoma, an epithelial-to-mesenchymal transition (EMT)-like process, which the ZEB1 gene has an essential role.

LncRNA-MEG3 inhibits cell proliferation and invasion by modulating Bmi1/RNF2 in cholangiocarcinoma

Cholangiocarcinoma (CCA) is a mortal cancer with gradually increasing incidences all over the world, whereas effective diagnosis and treatment for this disease are still lacking. As a classical long noncoding RNA (lncRNA), maternally expressed gene 3 (MEG3) has been reported to exhibit pivotal regulatory roles in the occurrence and development of various digestive system tumors. Nevertheless, the clinical relevance and biological function of MEG3 in CCA remain largely unclear. In this study, MEG3 expression was significantly downregulated in both CCA tissues and cells in comparison with that in nontumor controls, respectively, and this downexpression was prominently associated with advanced TNM stage, lymph node invasion, and poor survival. Moreover, decreased MEG3 was an independent forecaster of poor prognosis for CCA patients. Functionally, MEG3 overexpression inhibited CCA growth in vitro and in vivo. Enhanced MEG3 also suppressed migration and invasion of CCLP-1 and QBC939 cells by reversing epithelial-mesenchymal transition (EMT) process. On the contrary, the proliferation, metastasis, and EMT were facilitated via knocking down MEG3. In addition, the expression of B lymphoma Mo-MLV insertion region 1 (Bmi1) and RING finger protein 2 was impacted by gain or loss of MEG3, furthermore, the malignant processes induced by MEG3 knockdown were rescued by means of silencing Bmi1. These data suggested that MEG3 caused tumor suppressive effects partly through mediating polycomb repressive complex 1. Our findings elucidate that MEG3 exerts critical functions in CCA development and likely acts as a promising tumor indicator or intervention target for CCA.

Effect of lncRNA ZEB1-AS1 on proliferation, invasion and apoptosis of glioma U87 cells

This study aimed to investigate the effect of LncRNA ZEB1-AS1 on the proliferation, invasion and apoptosis of human glioma U87 cells. U87 glioma cells were divided into three groups. The Si group was transfected with LncRNA ZEB1-AS1 specific SiRNA. The NC group was transfected with non-specific scramble siRNA, and untransfected glioma cells were used as the blank group. After 48 h of transfection, the proliferation of U87 cells was detected by MTT assay, apoptosis of U87 cells was detected by flow cytometry, and Transwell invasion assay was used to detect cell invasion. The expression of LncZEB1-AS1 in Si group was significantly lower than that in the NC and blank groups (P<0.01). There was no statistical difference in the OD 490 between the three groups at 24 h (P>0.05). At 48 h, the Si group was significantly lower than the NC group and the blank group (P<0.01). After 48 h, the three groups showed a gradually increasing trend, but at all the time points, the Si group was always lower than the NC and blank groups (P<0.01). The OD values of the blank and NC groups were significantly higher than the same group at the previous time point (P<0.01). The OD values of Si group at 48 and 96 h were significantly higher than those at the previous time point (P <0.05). Although there was an upward trend between 72 and 48 h, the difference was not significant (P>0.05). Flow cytometry detected apoptosis in each group and found that the apoptosis rate in the Si group was significantly higher than that in the NC and blank groups (P<0.01). Inhibition of LncRNA ZEB1-AS1 can inhibit the proliferation and invasion of glioma U87 cells and promote apoptosis. LncRNA ZEB1-AS1 is expected to become a new target for the treatment of glioma.

Functions and roles of long noncoding RNA in cholangiocarcinoma

Cholangiocarcinoma (CCA) is one of the most fatal cancers in humans, with a gradually increasing incidence worldwide. The efficient diagnostic and therapeutic measures for CCA to reduce mortality are urgently needed. Long noncoding RNAs (lncRNAs) may provide the potential diagnostic and therapeutic option for suppressing the CCA development. LncRNAs are a type of non-protein-coding RNAs, which are larger than 200 nucleotides in length. Increasing evidence reveals that lncRNAs exhibit critical roles in the carcinogenesis and development of CCA. Deregulation of lncRNAs impacts the proliferation, migration, invasion, and antiapoptosis of CCA cells by multiple sophisticated mechanisms. Consequently, lncRNAs likely represent promising biomarkers or intervention targets of CCA. In this review, we summarize current studies regarding the biological functions and regulatory mechanisms of diverse lncRNAs in CCA.

LncRNA ZEB1-AS1 reduces liver cancer cell proliferation by targeting miR-365a-3p

Liver carcinoma is one of the most common malignancies worldwide. Previous studies have demonstrated that long non-coding RNAs (lncRNAs) are crucial mediators that participate in a wide range of molecular processes associated with carcinogenesis. However, little is known about the specific mechanisms that underlie the majority of lncRNAs. Many studies have indicated that lncRNAs affect microRNA (miRNA or miR) activities via physical base-paired binding, therefore serving as competing endogenous RNAs (ceRNAs) that indirectly regulate the expression of miRNA targets. In the current study, it was revealed that lncRNA zinc-finger E-box binding homeobox 1 antisense 1 (ZEB1-AS1) serves as a ceRNA for miR-365a-3p, functioning to positively modulate E2F transcription factor 2 (E2F2) expression in liver cancer cells. Additionally, reverse transcription-quantitative polymerase chain reaction demonstrated that levels of ZEB1-AS1 were abnormally upregulated in liver cancer and this was positively correlated with E2F2 expression. Furthermore, high levels of ZEB1-AS1 exhibited a trend for poor survival in patients with liver cancer. Western blot analysis demonstrated that ZEB1-AS1 silencing could reduce E2F2 expression. EdU staining and flow cytometry analysis indicated that downregulation of ZEB1-AS1 could suppress cell proliferation and decrease the S phase proportion of liver cancer cells, which was effectively reversed by the inhibition of miR-365a-3p. ZEB1-AS1 was also determined to be physically associated with miR-365a-3p, while miR-365a-3p was revealed to target the E2F2 3′UTR for degradation or translational repression. The results also demonstrated that ZEB1-AS1 positively regulates E2F2 expression by competitively binding to miR-365a-3p. It was further revealed to enhance liver cancer cell proliferation. Thus, these results indicate that ZEB1-AS1 is required for liver cancer progression in a ceRNA dependent manner. ZEB1-AS1 may therefore be a potential target for liver cancer intervention.

Long non-coding RNA ZEB1-AS1 regulates miR-200b/FSCN1 signaling and enhances migration and invasion induced by TGF-β1 in bladder cancer cells

Background

The effect of competing endogenous RNA (ceRNA) can regulate gene expression by competitively binding microRNAs. Fascin-1 (FSCN1) plays an important role in the regulation of cellular migration and invasion during tumor progression, but how its regulatory mechanism works through the ceRNA effect is still unclear in bladder cancer (BLCA).

Methods

The role of fascin-1, miR-200b, and ZEB1-AS1 in BLCA was investigated in vitro and in vivo. The interaction between fascin-1, miR-200b, and ZEB1-AS1 was identified using bioinformatics analysis, luciferase activity assays, RNA-binding protein immunoprecipitation (RIP), quantitative PCR, and western blotting. Loss (or gain)-of-function experiments were performed to investigate the biological roles of miR-200b and ZEB1-AS1 on migration, invasion, proliferation, cell apoptosis, and cell cycle.

Results

ZEB1-AS1 functions as a competing endogenous RNA in BLCA to regulate the expression of fascin-1 through miR-200b. Moreover, the oncogenic long non-coding RNA ZEB1-AS1 was highly expressed in BLCA and positively correlated with high tumor grade, high TNM stage, and reduced survival of patients with BLCA. Moreover, ZEB1-AS1 downregulated the expression of miR-200b, promoted migration, invasion, and proliferation, and inhibited apoptosis in BLCA. Furthermore, we found TGF-β1 induced migration and invasion in BLCA by regulating the ZEB1-AS1/miR-200b/FSCN1 axis.

Conclusion

The observations in this study identify an important regulatory mechanism of fascin-1 in BLCA, and the TGF-β1/ZEB1-AS1/miR-200b/FSCN1 axis may serve as a potential target for cancer therapeutic purposes.

Electronic supplementary material

The online version of this article (10.1186/s13046-019-1102-6) contains supplementary material, which is available to authorized users.

lncRNA ZEB1-AS1 promotes pulmonary fibrosis through ZEB1-mediated epithelial-mesenchymal transition by competitively binding miR-141-3p

Long non-coding RNAs (lncRNAs) have been reported to be involved in various pathophysiological processes in many diseases. However, the role and mechanism of lncRNAs in pulmonary fibrosis have not been explicitly delineated. In the present study, we found that lncRNA ZEB1 antisense RNA 1 (ZEB1-AS1) is upregulated in the lungs of BLM-induced rats and TGF-β1-induced RLE-6TN cells, and positively correlated with the levels of ZEB1, an epithelial-mesenchymal transition (EMT) master regulator. Knockdown of ZEB1-AS1 alleviated BLM-induced fibrogenesis, in vivo, via inhibiting EMT progress. Mechanistically, we identified that ZEB1-AS1 promoted fibrogenesis in RLE-6TN cells and ZEB1-AS1 silencing inhibited TGF-β1-induced fibrogenesis through modulation of miR-141-3p. Further experiments revealed that ZEB1-AS1 acted as competing endogenous RNA (ceRNA) of miR-141-3p: forced expression of ZEB1-AS1 reduced the expression of miR-141-3p to activate Zinc-finger Ebox Binding Homeobox 1 (ZEB1) in RLE-6TN cells. In addition, we found that upregulation of miR-141-3p prevented fibrogenesis by targeting ZEB1. Therefore, our finding suggested lncRNA ZEB1-AS1 as a new profibrotic molecule that acts as a regulator of miR-141-3p/ZEB1 axis during lung fibrosis and demonstrated ZEB1-AS1 as a potential therapeutic target for the prevention and treatment of pulmonary fibrosis.

LncRNA ZEB1-AS1 inhibits renal fibrosis in diabetic nephropathy by regulating the miR-217/MAFB axis

Diabetic nephropathy (DN) is a common chronic microvascular complication of diabetes, characterized by the deposition of extracellular matrix (ECM) proteins.

Long non-coding RNA ZEB1-AS1 indicates poor prognosis and promotes melanoma progression through targeting miR-1224-5p

Long non-coding RNAs (lncRNAs) have critical roles in various types of cancer, but their roles in the development of melanoma and the underlying molecular mechanisms remain to be fully elucidated. In the present study, the role of zinc finger E-box binding homeobox 1 antisense RNA 1 (ZEB1-AS1) in melanoma was assessed. The expression levels of ZEB1-AS1 were increased in melanoma cell lines and tumor tissues as indicated by reverse transcription-quantitative polymerase chain reaction analysis. Kaplan-Meier analysis suggested that higher expression of ZEB1-AS1 predicts poor prognosis of melanoma patients. Furthermore, knockdown of ZEB1-AS1 inhibited the proliferation, migration and invasion of melanoma, suggesting a role of ZEB1-AS1 in the development and progression of melanoma. In addition, a luciferase reporter assay confirmed that the expression of miR-1224-5p was directly regulated by ZEB1-AS1. Transfection with miR-1224-5p mimics reduced the levels of ZEB1-AS1 and the proliferation, migration and invasion of melanoma. In conclusion, ZEB1-AS1 enhances the proliferation, migration and invasion of melanoma, at least in part by inhibiting the expression of miR-1224-5p, and its overexpression is associated with poor survival of melanoma patients. In addition, the ZEB1-AS1/miR-1224-5p interaction may be a promising therapeutic target for melanoma treatment.

LncRNA ZEB1-AS1/miR-409-3p/ZEB1 feedback loop is involved in the progression of non-small cell lung cancer

Emerging evidence has illustrated that long noncoding RNA (LncRNA) ZEB1 antisense RNA 1 (ZEB1-AS1) involved in the development of various type of human cancers. However, the role of ZEB1-AS1 in non-small cell lung cancer (NSCLC) is still elusive and poorly understood. The present study aimed to provide functional evidence and elucidate the molecular mechanisms by which the ZEB1-AS1 promotes oncogenesis of NSCLC. Our study found that ZEB1-AS1 was upregulated in NSCLC cells and knockdown of ZEB1-AS1 significantly inhibited cell growth and induced cell apoptosis. Mechanically, miR-409-3p was confirmed as a direct target of ZEB1-AS1 and negatively regulated by ZEB1-AS1 via competing endogenous RNA (ceRNA) mechanism; miR-409-3p inhibited ZEB1 expression by directly binding to the 3'UTR. Importantly, as predicted by JASPAR and further confirmed by luciferase reporter gene and ChIP assays, we found ZEB1 could bind to the promoter region of ZEB1-AS1 to activate its expression. Restoration of ZEB1 could partially abolished the action of ZEB1-AS1 silencing on cell proliferation and apoptosis. Collectively, the results suggested that ZEB1-AS1/miR-409-3p/ZEB1 constitutes a positive feedback loop to promote the tumorigenesis of NSCLC, highlighting the possibility of improving NSCLC treatment by targeting the ZEB1-AS1 signaling pathway.

Long noncoding RNA ZEB1-AS1 promotes the tumorigenesis of glioma cancer cells by modulating the miR-200c/141-ZEB1 axis

Long noncoding RNA Zinc Finger E-box-binding homeobox 1 antisense 1 (ZEB1-AS1) reportedly participates in the tumorigenesis of various cancers. However, the clinical significance and biological functions of ZEB1-AS1 in glioma remain virtually unknown. Here, we show that ZEB1-AS1 expression was higher in glioma tissues and cell lines than in corresponding noncancerous samples and primary normal human astrocytes, respectively. The positive correlation of ZEB1-AS1 expression with the poor prognosis and progressive histological stages of glioma patients was clinically proven. In vitro assays revealed that silencing ZEB1-AS1 inhibited glioma cancer-cell growth and motility. Xenograft experiments confirmed that ZEB1-AS1 depletion attenuated tumor growth and metastasis. Dual-luciferase report assay showed that ZEB1-AS1 directly regulated microRNA-200c/141 (miR-200c/141) in glioma cells, which was confirmed by RNA immunoprecipitation assay. Furthermore, the inhibition of miR-200c/141 partially balanced the inhibition effects of cell proliferation and motility induced by ZEB1-AS1 depletion on U87 cells. Additionally, ZEB1-AS1 can regulate ZEB1 through miR-200c/141. Hence, ZEB1-AS1 directly regulated miR-200c/141 in glioma cells and relieved the inhibition of ZEB1 caused by miR-200c/141. Overall, this study revealed a novel regulatory mechanism between ZEB1-AS1 and the miR-200c/141-ZEB1 axis. The interaction between ZEB1-AS1 and miR-200c/141-ZEB1 axis was involved in the progression of glioma cells. Therefore, targeting this interaction was a promising strategy for glioma treatment.