Increased expression of ZEB1-AS1 correlates with higher histopathological grade and promotes tumorigenesis in bladder cancer

A review on the role of ZEB1-AS1 in human disorders

ZEB1 Antisense RNA 1 (ZEB1-AS1) is a type of RNA characterized as long non-coding RNA (lncRNA). This lncRNA has important regulatory roles on its related gene, Zinc Finger E-Box Binding Homeobox 1 (ZEB1). In addition, role of ZEB1-AS1 has been approved in diverse malignancies such as colorectal cancer, breast cancer, glioma, hepatocellular carcinoma and gastric cancer. ZEB1-AS1 serves as a sponge for a number of microRNAs, namely miR-577, miR-335-5p, miR-101, miR-505-3p, miR-455-3p, miR-205, miR-23a, miR-365a-3p, miR-302b, miR-299-3p, miR-133a-3p, miR-200a, miR-200c, miR-342-3p, miR-214, miR-149-3p and miR-1224-5p. In addition to malignant conditions, ZEB1-AS1 has functional role in non-malignant conditions like diabetic nephropathy, diabetic lung, arthrosclerosis, Chlamydia trachomatis infection, pulmonary fibrosis and ischemic stroke. This review outlines different molecular mechanisms of ZEB1-AS1 in a variety of disorders and highlights its importance in their pathogenesis.

Positive Reciprocal Feedback of lncRNA ZEB1-AS1 and HIF-1α Contributes to Hypoxia-Promoted Tumorigenesis and Metastasis of Pancreatic Cancer

Background

Many studies have reported the roles of the extracellular hypoxia microenvironment in the tumorigenesis and metastasis of multiple cancers. However, long noncoding RNAs (lncRNAs) that induce cancer oncogenicity and metastasis of pancreatic cancer (PC) under hypoxia conditions remain unclear.

Methods

In PC cells, the expression levels of lncRNAs in different conditions (normoxia or hypoxia) were compared through RNA sequencing (RNA-seq). The effects of the zinc finger E-box-binding homeobox 1 (ZEB1-AS1) antisense lncRNA on PC cells cultured in normoxia/hypoxia medium were measured through gain and loss-of-function experiments. Fluorescence in situ hybridization and luciferase reporter assays in addition to in vivo studies were utilized to explore the adaptive mechanisms of ZEB1-AS1 in the hypoxia-promoted proliferation, migration, and invasion ability of PC cells. Moreover, the level of ZEB1-AS1 and its associated targets or pathways were investigated in both PC and pancreatic normal tissues.

Results

RNA-seq revealed that ZEB1-AS1 was significantly upregulated in PC cells under hypoxia conditions. The ZEB1-AS1 expression level was closely associated with poor prognosis of PC patients. Knockdown of ZEB1-AS1 suppressed the proliferation, migration, and invasion of PC cells in vitro as well as PC xenograft tumor growth in vivo. In PC cells, RNAi-mediated reduction of ZEB1-AS1 inhibited zinc finger E-box-binding homeobox 1 (ZEB1), while ZEB1-AS1 overexpression rescued ZEB1 expression, indicating that ZEB1-AS1 promotes ZEB1 expression. Moreover, hypoxia-inducible factor-1α (HIF-1α)induced the expression of ZEB1-AS1 by binding to the ZEB1-AS1 promoter, which contains a putative hypoxia response element (HRE). Mechanistically, ZEB1-AS1 scaffolded the interaction among HIF-1α, ZEB1, and histone deacetylase 1 (HDAC1), leading to deacetylation-mediated stabilization of HIF-1α. We further revealed that ZEB1 induced the deacetylase capacity of HDAC1 to suppress the acetylation or degradation of HIF-1α, improving HIF-1α assembly. Thus, hypoxia-induced ZEB1-AS1 facilitated ZEB1 transcription and the stability of HIF-1α, which promoted the metastasis of PC cells. Clinically, dysregulated ZEB1 and HIF-1α expression was significantly correlated with histological grade, lymphatic metastasis, and distant metastasis in PC patients.

Conclusions

Our results emphasized that the positive reciprocal loop of HIF-1α/ZEB1-AS1/ZEB1/HDAC1 contributes to hypoxia-promoted oncogenicity and PC metastasis, indicating that it might be a novel therapeutic target for PC.

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.

Long noncoding RNA ZEB1-AS1 affects paclitaxel and cisplatin resistance by regulating MMP19 in epithelial ovarian cancer cells

PURPOSE

The long noncoding RNA (lncRNA) ZEB1-AS1 is reported overexpressed in sensitive ovarian cancer cells A2780 compared with paclitaxel (PTX)-and cisplatin (DDP)- resistant. However, the function and mechanism of ZEB1-AS1 in EOC cells still unknown.

METHODS

We used quantitative real-time PCR (qPCR) to detect ZEB1-AS1 expression in A2780 and A2780/R cells. A combination of siRNA, plasmids, CCK8 and flow cytometry was used to detect the effect of ZEB1-AS1 on ovarian cancer cell A2780 PTX and DDP resistance. Transcriptome sequencing, qPCR, and western blot were used for further mechanistic studies.

RESULTS

ZEB1-AS1 depletion using siRNA in chemosensitive A2780 cells significantly increased PTX and DDP resistance. In contrast, ZEB1-AS1 overexpression in PTX- and DDP-resistant A2780/resistant (A2780/R) cells reversed the observed drug resistance. Thus, ZEB1-AS1 plays an important role in PTX and DDP resistance in EOC cells. However, quantitative real-time PCR (qPCR) and western blot results suggested that ZEB1-AS1 did not regulate chemoresistance through regulation of ZEB1 protein. We used sequencing to detect mRNA expression changes in A2780 cells after ZEB1-AS1 silencing. The results indicated that MMP19 was the likely downstream factor of ZEB1-AS1. We further examined whether ZEB1-AS1 played an important role in chemoresistance by silencing MMP19 in ZEB1-AS1-overexpressing cells. CCK8 assay results suggested that MMP19 knockdown promoted ZEB1-AS1-induced chemoresistance to PTX and DDP in A2780 cells.

CONCLUSION

This study is the first to reveal that ZEB1-AS1 plays a pivotal role in cancer chemoresistance.

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.

Clinical value of long noncoding RNA ZEB1 anti-sense1 in cancer patients: A meta-analysis

BACKGROUND

The high expression of long noncoding RNA ZEB1 anti-sense1 (ZEB1-AS1) has been reported in several types of cancer. However, most studies investigating this phenomenon were either case reports or used small patient samples. The objective of this meta-analysis was to clarify the potential clinical values of ZEB1-AS1 in various cancers.

MATERIALS AND METHODS

The PubMed-MEDLINE, Web of Science, and EMBASE databases were searched, using systematic search terms, to find relevant research reports on this subject. The combined hazards ratios (HRs) and corresponding 95% confidence intervals (CIs) were calculated to explore the association between ZEB1-AS1 expression and overall survival (OS). The combined odd ratios (ORs) were calculated to evaluate the association between ZEB1-AS1 expression and pathological parameters. Data analysis was conducted in R software version 3.4.2. and Stata version 12.0 (College Station, TX: Stata Corp LP).

RESULTS

Ten studies including 963 cancer patients were selected as suitable for this study. The pooled hazards ratio (HR) indicated that high ZEB1-AS1 expression was strongly associated with poor OS (pooled HR = 2.26, 95% CI: 1.80-2.85, P < .0001) in the Chinese cancer patients. Also, a high expression of ZEB1-AS1 was related to metastasis (pooled HR = 3.38, 95% CI: 1.91-6.00, P < .0001), and advanced tumor stage (pooled HR = 0.48, 95% CI: 0.29-0.81, P = .005). The up-regulation of ZEB1-AS1 was not significantly associated with histological differentiation (P = .39), sex (P = .001), and age (P = .372) of cancer patients.

CONCLUSION

The high expression of ZEB1-AS1 significantly predicted poor OS, poor metastasis, and high tumor stage in cancer patients, demonstrating that high ZEB1-AS1 expression may serve as a biomarker of poor prognosis in the Chinese cancer patients.

LncRNA ZEB1-AS1 Regulates Colorectal Cancer Cells by MiR-205/YAP1 Axis

Background

Recent studies demonstrated that long non-coding RNAs (lncRNAs) were involved in many biological processes. Dysregulated lncRNAs are related to many cancers, including colorectal cancer (CRC). However, the molecular mechanism of lncRNA ZEB1-AS1 in CRC is not clear.

Methods

LncRNA ZEB1-AS1, miR-205, and YAP1 expression were measured by quantitative reverse transcriptase PCR (QRT-PCR). YAP1 protein expression was measured by western blotting. Cell viability was measured by MTT assay. Cell apoptosis was detected by flow cytometry. Luciferase reporter assay was used to confirm the relationship between ZEB1-AS1, miR-205, and YAP1.

Results

LncRNA ZEB1-AS1 and YAP1 was upregulated in CRC tissues. The expression of YAP1 was positively correlated with ZEB1-AS1. Knockdown of ZEB1-AS1 inhibited cell viability and induced apoptosis in CRC cell line SW480 and HCT116 which could be reversed by overexpression of YAP1. ZEB1-AS1 targeted and regulated miR-205 which could directly bind to YAP1. Meanwhile, ZEB1-AS1 regulated the expression of YAP1 via modulating miR-205.

Conclusion

Long non-coding RNA ZEB1-AS1 silencing could inhibit cell proliferation and induce apoptosis of colorectal cancer via regulating miR-205 and YAP1.

The Relationship Between ZEB1-AS1 Expression and the Prognosis of Patients With Advanced Gastric Cancer Receiving Chemotherapy

Long noncoding RNA ZEB1 antisense RNA 1 plays a vital role in tumorigenesis and metastasis. However, the role of ZEB1 antisense RNA 1 in gastric cancer remains unclear. This study aimed to investigate the expression level of ZEB1 antisense RNA 1 in gastric cancer tissues and evaluate its association with clinicopathological features and prognosis of patients with advanced gastric cancer receiving chemotherapy. The expression levels of ZEB1 antisense RNA 1 were examined in 224 pairs of gastric cancer and adjacent noncancerous tissues by quantitative real-time polymerase chain reaction. The associations between ZEB1 antisense RNA 1 expression and clinicopathological features or survival of patients with advanced gastric cancer were assessed. The results showed that the expression levels of ZEB1 antisense RNA 1 in gastric cancer tissues were significantly higher than those in the paracancerous tissues (P < .001). Moreover, the high ZEB1 antisense RNA 1 expression was associated with tumor, nodes, and metastases stage IV (P = .018) and loss of E-cadherin expression (P = .033). Multivariate Cox hazards regression analysis revealed that high ZEB1 antisense RNA 1 expression was an independent risk factor for predicting poor prognosis in patients with advanced gastric cancer (hazard ratio = 1.530, 95% confidence interval, 1.052-2.224, P = .026). In conclusion, the present findings suggest that ZEB1 antisense RNA 1 is an independent prognostic factor for patients with advanced gastric cancer receiving chemotherapy.

lncRNA ZEB1-AS1 promotes migration and metastasis of bladder cancer cells by post-transcriptional activation of ZEB1

The prognosis for patients with metastatic bladder cancer (BCa) is poor, and has not been improved by current treatment methods. Long noncoding RNAs (lncRNAs) are involved in the pathology of various tumors, including bladder cancer. However, the role of zinc finger E-box-binding homeobox 1-antisense 1 (ZEB1-AS1) in BCa progression and metastasis remains unclear. The present study determined the expression level of ZEB1-AS1 in BCa and additionally investigated the functional role of ZEB1-AS1 in BCa metastasis. Reverse transcription quantitative polymerase chain reaction analysis showed that ZEB1-AS1 was upregulated in BCa cells compared with normal epithelial cells. Functionally, knockdown of ZEB1-AS1 suppressed BCa cell migration and invasion in vitro, and metastasis in vivo. Mechanistic investigations revealed that ZEB1-AS1 bound to heterogenous nuclear ribonucleoprotein D0 (AUF1), thereby activating the translation of ZEB1 mRNA without affecting its mRNA level. In addition, ZEB1-AS1 was significantly upregulated in BCa tissues and muscle-invasive BCa cases. ROC curve analysis demonstrated that ZEB1-AS1 expression was associated with metastasis in patients with BCa. In conclusion, the data from the present study demonstrated that ZEB1-AS1 induced BCa metastasis via an AUF1-mediated translation activation of ZEB1 mRNA mechanism. ZEB1-AS1 may serve as a promising target for clinical intervention in advanced BCa.

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.

Prognostic value of long non-coding RNA ZEB1-AS1 in Chinese cancer patients: A Meta-analysis

BACKGROUND

Aberrant expression of long non-coding RNA Zinc finger E-box binding homeobox 1 antisense 1 (lncRNA ZEB1-AS1) can be detected in numerous malignancies. Therefore, a meta-analysis had been carried out in this study, aiming to examine the prognostic value of lncRNA ZEB1-AS1 in malignancies.

METHODS

Electronic databases, such as PubMed, OVID as well as Web of Science, had been systemically retrieved from inception to February 14th, 2019. Besides, the hazard ratios (HRs), together with the corresponding 95% confidence intervals (CIs), had also been analyzed for determining the association of lncRNA ZEB1-AS1 expression with the overall survival (OS) and recurrence-free survival (RFS). In addition, the pooled odds ratios (ORs) would also be computed using the Stata SE12.0 software for evaluating the relationship of lncRNA ZEB1-AS1 expression with pathological factors.

RESULTS

A total of 21 original studies involving 1801 cancer patients had been enrolled into the current meta-analysis. As suggested by the pooled HR, high expression of lncRNA ZEB1-AS1 had displayed marked correlation with OS (HR = 2.16, 95% CI: 1.89-2.47) among cancer patients, and no significant heterogeneity was detected. Additionally, high expression of lncRNA ZEB1-AS1 was also markedly associated with RFS among cancer patients (pooled HR = 2.55, 95% CI: 1.61-4.03). Besides, the expression of lncRNA ZEB1-AS1 had displayed marked correlation with poor histological grade (PHG) (OR = 2.86, 95% CI: 2.11-3.87), high tumor stage (HTS) (OR = 3.81, 95% CI: 2.72-5.34) as well as lymph node metastasis (LNM) (OR = 3.33, 95% CI: 2.47-4.49). Additionally, no distinct asymmetry had been detected for RFS, PHG as well as HTS based on Begg funnel plot.

CONCLUSIONS

Taken together, high expression of lncRNA ZEB1-AS1 can predict the dismal OS, RFS, LNM, PHG, and HTS, indicating that lncRNA ZEB1-AS1 can be potentially used as a new biomarker to predict the dismal prognosis for cancer patients.

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.

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.

LncRNA as a diagnostic and prognostic biomarker in bladder cancer: a systematic review and meta-analysis

Background

Bladder cancer is one of the most common urinary malignancies, and has a high recurrence rate and poor outcomes. In order to identify novel diagnostic and prognostic biomarkers for bladder cancer, we conducted a meta-analysis to analyze the association between long non-coding RNA (lncRNA) expression and survival in bladder cancer.

Materials and methods

We searched literature from databases using our inclusion and exclusion criteria. STATA 14.0 software was used to analyze the data from collected studies and to construct the forest plots. A different effect size was selected for each meta-analysis.

Results

After selection, 30 articles were found to be eligible. The present meta-analysis contains data from 13 articles about clinicopathological characteristics, six articles about diagnosis, and 16 articles about prognosis. In the present study, we found that many lncRNAs could function as potential diagnostic and prognostic markers in bladder cancer. Among these findings, UCA1 was expected to be a diagnostic biomarker for bladder cancer, while the aberrant expression of HOTAIR and GAS5 was associated with poor disease-free survival/recurrence-free survival/disease-specific survival.

Conclusion

Overall, the present study is the first meta-analysis to assess the association between expression of lncRNAs and clinical value in patients with bladder cancer. LncRNAs hold promise as novel diagnostic and prognostic markers in bladder cancer.

The prognostic value of long noncoding RNA ZEB1-AS1 on clinical outcomes in human cancer

Background: Although growing evidence have demonstrated that long non-coding RNA ZEB1-AS1 was aberrantly expressed in various types of cancers and can be used as a prognostic marker in cancer, the results remain inconclusive. Therefore, we performed this meta-analysis to evaluate the prognostic value of ZEB1-AS1 in human cancer.

Methods: A literature survey was conducted for all eligible studies by searching the following online databases: PubMed and Embase. The pooled odds ratios (ORs) or hazard ratios (HRs) with a 95 % confidence interval (95 % Cl) were computed to demonstrate its prognostic value.

Results: A total of 14 studies with 1096 individuals were included to evaluate the association of ZEB1-AS1 with clinicopathological features and overall survival (OS). In the pooled analyses stratified by clinicopathological features, ZEB1-AS1 expression was significantly related to depth of tumor (OR=2.92, 95% CI 1.22-7.02), poor histological differentiation (OR=2.72, 95% CI: 1.92-3.86), lymph node metastasis (OR=3.93, 95% CI: 2.65-5.84), distant metastasis (OR=5.34, 95% CI: 2.85-10.02) and tumor stage (OR=2.46, 95% CI 1.42-4.24), but not to tumor size (OR=1.25, 95% CI 0.79-1.96). Altered ZEB1-AS1 expression was found to be an indicator of worse prognosis in OS (HR = 1.94, 95% CI: 1. 66-2.22) among tumor patients.

Conclusions: High ZEB1-AS1expression was associated poor clinical outcome and it can serve as a novel predictive biomarker in various cancers.

Long noncoding RNA LINC00152 promotes cell proliferation through competitively binding endogenous miR-125b with MCL-1 by regulating mitochondrial apoptosis pathways in ovarian cancer

Recently, an increasing number of studies have focused on the key function of long noncoding RNAs (lncRNAs) in biological activity. Abnormal lncRNA expression was found to relate to the development and pathogenesis of multiple cancers. LncRNA LINC00152 served as an oncogene in multiple cancers; however, its role in ovarian cancer remains unknown. In our research study, LINC00152 was upregulated in ovarian cancer tissues and cell lines. An increasing LINC00152 level was positively correlated with the histological grade, clinical stage, and poor prognosis of ovarian cancer patients. In addition, knockdown of LINC00152 reduced cell growth, induced cell apoptosis, and suppressed tumor growth. Moreover, we revealed that LINC00152 and Myeloid cell leukemia‐1 (MCL‐1) were targeted by miR‐125b and had the same miR‐125b combining site. The miR‐125b level was negatively correlated with the expression of LINC00152, while MCL‐1 was positively related to the LINC00152 level. MiR‐125b could affect LINC00152 levels as evaluated by qRT‐PCR. Finally, we affirmed that LINC00152 mediated cell proliferation by affecting MCL‐1 expression and MCL‐1‐mediated mitochondrial apoptosis pathways and by working as a competitive endogenous RNA (ceRNA) of miR‐125b. In summary, based on ceRNA theory, the combined research on miR‐125b and MCL‐1, and taking LINC00152 as a new study point, we provide new insight into the molecular mechanism of reversing cell proliferation in ovarian cancer.

Increased expression of lncRNA ZEB1-AS1 in non-small cell lung cancer is associated with poor prognosis

BACKGROUND

Dysregulated long non-coding RNAs (lncRNAs) play critical roles in tumorigenesis and tumor progression. The purpose of this study was to investigate the relationship between lncRNA ZEB1-AS1 expression and non-small cell lung cancer (NSCLC) clinicopathological characteristics and prognosis.

METHODS

Expression levels of lncRNA ZEB1-AS1 in 183 NSCLC specimens were determined by quantitative real-time PCR (qRT-PCR). To clarify the clinical significance of lncRNA ZEB1-AS1 in NSCLC, we further explored the relationship between lncRNA ZEB1-AS1 expression and overall survival (OS).

RESULTS

In the present study, we found that lncRNA ZEB1-AS1 was upregulated in NSCLC tissues compared to adjacent non-tumor tissues. In addition, upregulated lncRNA ZEB1-AS1 expression was significantly associated with lymph node metastasis and TNM stage (P<0.05). Furthermore, patients with increased expression of lncRNA ZEB1-AS1 had poor OS (HR=3.202, 95% CI=2.018-5.078, P<0.001). Multivariate Cox proportional hazards model analysis demonstrated that high lncRNA ZEB1-AS1 expression was an independent poor prognostic factor for NSCLC patients.

CONCLUSION

Our study suggests that increased expression of lncRNA ZEB1-AS1 is related to adverse prognosis of NSCLC and may be a new prognostic biomarker and potential therapeutic target for NSCLC intervention.

The significant prognostic value of ZEB1-AS1 up-regulation in patients with cancer

Zinc finger E-box binding homeobox 1 antisense 1 (ZEB1-AS1) is a long non-coding RNA, which has found to unregulated in various kinds of cancer. This meta-analysis was conducted to demonstrate the association between ZEB1-AS1 expression levels and clinical outcome or prognosis of cancer patients.10 studies with 783 cancer patients were included in this meta-analysis by retrieving 5 databases (PubMed Central, EMBASE, Cochrane Library, Wiley Online Library and Medline).The result showed that overexpression of ZEB1-AS1 is significantly correlated with poor OS (Hazard ratio, HR=2.45, 95% confidence interval, CI: 1.89-3.16). ZEB1-AS1 expression levels were also associated with clinicopathological parameters including lymph node metastasis (Yes vs. No; OR=4.00, 95%CI: 2.23-7.17, P<0.00001), histologic differentiation (Moderate + poor vs. Well; OR=2.72, 95% CI: 1.69-4.37, p<0.0001), tumor metastasis and invasion (Yes vs. No; OR =2.52, 95%CI: 1.12-5.68, P=0.03) and TNM stage (III+IV vs. I+II; OR=2.76, 95 %CI 1.46-5.21, P=0.002). However, ZEB1-AS1 expression was not significantly associated with patients' gender (Male vs. Female; OR=1.20, 95% CI: 0.87-1.66; P=0.27).This meta-analysis indicated the potential value of ZEB1-AS1 as a biomarker for predicting a poor prognosis in patients with cancer.

The utility of long non-coding RNA ZEB1-AS1 as a prognostic biomarker in human solid tumors: A meta-analysis

PURPOSE

This meta-analysis aims to assess the prognostic value of long non-coding RNA ZEB1-AS1 in human solid tumors.

METHODS

We searched the available databases up to January 2018. Pooled hazard ratios (HRs) and the corresponding 95% confidence intervals (CIs) were used to examine the prognostic impact of ZEB1-AS1 on patient survival.

RESULTS

Eight eligible studies with a total of 586 patients were enrolled. A significant association was observed between ZEB1-AS1 overexpression and poor overall survival (OS; HR = 2.195, 95% CI: 1.749-2.755) as well as unfavorable recurrence-free survival (pooled HR = 2.205, 95% CI: 1.486-3.270), and no heterogeneity was found across these studies (p = .962, I² = 0%). Subsequent subgroup analyses showed that cancer type, sample size, follow up months, and HR estimation method did not alter the significant prognostic value of ZEB1-AS1. ZEB1-AS1 expression was indicated to be an independent prognostic factor for tumor OS (pooled HR = 2.177, 95% CI:1.545-3.069). Furthermore, we found that increased ZEB1-AS1 expression was significantly associated with tumor stage [III-IV vs. I-II: odds ratio (OR) = 1.644, 95% CI: 1.201-2.249] and lymph node metastasis (Positive vs. Negative: OR = 2.413, 95% CI: 1.504-3.873).

CONCLUSION

High expression level of ZEB1-AS1 was associated with unfavorable survival outcome for cancer patients, and ZEB1-AS1 could be used as a prognostic predictor for cancers.

microRNA‑574 inhibits cell proliferation and invasion in glioblastoma multiforme by directly targeting zinc finger E‑box‑binding homeobox 1

Accumulated evidence has demonstrated that dysregulation of microRNAs (miRNAs) contributes to tumourigenesis and tumour development of glioblastoma multiforme (GBM). Therefore, miRNAs may be promising candidates in the development of prognosis biomarkers and effective therapeutic targets for patients with GBM. A number of studies have reported that miRNA‑574 (miR‑574) is aberrantly expressed in multiple types of human cancers. However, the expression pattern, biological functions and molecular mechanism of miR‑574 in GBM are yet to be elucidated. Therefore, the present study aimed to determine the expression level and biological functions of miR‑574 in GBM and the underlying molecular mechanisms. In the present study, miR‑574 levels were measured by reverse transcription‑quantitative polymerase chain reaction (RT‑qPCR) and were demonstrated to be significantly downregulated in human GBM tissues and cell lines. Functional experiments indicated that restored expression of miR‑574 using mimics led to the inhibition of the cell proliferation and invasion of GBM cells, as determined by Cell Counting kit‑8 and Matrigel invasion assays, respectively. In addition, bioinformatics analysis predicted that zinc finger E‑box‑binding homeobox 1 (ZEB1) may be a target of miR‑574. Subsequent RT‑qPCR, western blot analysis and luciferase reporter assays confirmed that ZEB1 was a direct target of miR‑574 in GBM. Additionally, ZEB1 was demonstrated to be upregulated and inversely correlated with miR‑574 expression in clinical GBM tissues. Rescue experiments demonstrated that overexpression of ZEB1 attenuated the inhibitory effects of miR‑574 on the proliferation and invasion of GBM cells. Overall, the results of the present study highlighted the potential tumour inhibitory roles of miR‑574 in GBM, thereby indicating that miR‑574 may be a novel and efficient therapeutic target for the treatment of patients with GBM.

Clinical Values of Long Non-coding RNAs in Bladder Cancer: A Systematic Review

Background: Increasing evidence shows that dysregulated expression of long non-coding RNAs (lncRNAs) can serve as diagnostic or prognostic markers in bladder cancer. The aim of this study was to evaluate the clinical values of dysregulated lncRNAs in bladder cancer.

Methods: Eligible studies were systematically searched in PubMed, Embase, and Web of Science databases from inception to December 2017. Odds ratios (OR) were calculated to investigate the correlation between lncRNAs and clinicopathological parameters. Pooled hazard ratios (HR) and 95% confidence interval (CI) were calculated to explore the prognostic value of lncRNAs in bladder cancer. Pooled diagnostic parameters were also calculated to estimate the performance of lncRNAs in diagnosing bladder cancer. All statistical analyses were performed by using STATA 13.1 program.

Results: A total of 37 relevant studies were included to the present systematic review according to the inclusion and exclusion criteria, including 26 on clinicopathological parameters, 19 on prognosis, and 7 on diagnosis. For clinicopathological parameters, MALAT1 expression was significantly associated with lymph node metastasis (OR = 2.731; 95% CI: 1.409–5.292; p = 0.003), and high-level expression of XIST was related to larger tumor size (OR = 2.473; 95% CI: 1.159–5.276; p = 0.019) and higher TNM stage (OR = 0.400; 95% CI, 0.184–0.868; p = 0.020). For the prognostic values, the most significant association was observed between increased expressions of SPRY4-IT1 and poor overall survival (OS) (HR = 3.716; 95% CI: 2.084–6.719; p < 0.001); high MALAT1 expression was significantly associated with poor OS (HR = 1.611; 95% CI: 1.076–2.412; p = 0.020). For the diagnostic values, UCA1 expression profile achieved a combined AUC of 0.92, with sensitivity of 0.84 and specificity of 0.89 in distinguishing patients with bladder cancer from non-cancerous controls.

Conclusions: In summary, systematic review elaborated that abnormal lncRNAs expression can serve as potential markers for prognostic evaluation in bladder cancer patients. In addition, the diagnostic meta-analysis concluded that abnormally expressed UCA1 can function as potential diagnostic markers for bladder cancer.

Interplay between long noncoding RNA ZEB1-AS1 and miR-101/ZEB1 axis regulates proliferation and migration of colorectal cancer cells

Long noncoding RNAs (lncRNAs) are dysregulated in many diseases. MicroRNA-101 (miR-101) functions as a tumor suppressor by directly targeting ZEB1 in various cancers. However, the potential mechanism of lncRNA ZEB1-AS1 and miR-101/ZEB1 axis in CRC remains unknown. In this study, we further investigated the potential interplay between miR-101/ZEB1 axis and lncRNA ZEB1-AS1 in colorectal cancer (CRC). Results showed that ZEB1-AS1 was upregulated in CRC tissues and cells. MiR-101 was downregulated in CRC tissues and negatively correlated with ZEB1-AS1 and ZEB1 expression levels in CRC. Functional experiments showed that, consistent with ZEB1-AS1 depletion, miR-101 overexpression and ZEB1 depletion inhibited the proliferation and migration of CRC cells. Overexpression of miR-101 partially abolished the effects of ZEB1-AS1 on the proliferation and migration of these cells. Moreover, combined ZEB1-AS1 depletion and miR-101 overexpression significantly inhibited cell proliferation and migration of the CRC cells. Hence, ZEB1-AS1 functioned as a molecular sponge for miR-101 and relieved the inhibition of ZEB1 caused by miR-101. This study revealed a novel regulatory mechanism between ZEB1-AS1 and miR-101/ZEB1 axis. The interplay between ZEB1-AS1 and miR-101/ZEB1 axis contributed to the proliferation and migration of CRC cells, and targeting this interplay could be a promising strategy for CRC treatment.

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

Long non-coding RNAs (lncRNAs) recently emerge as a novel class of non-coding RNAs (ncRNAs) with larger than 200 nucleotides in length. Due to lack an obvious open reading frame, lncRNAs have no or limited protein-coding potential. To date, accumulating evidence indicates the vital regulatory function of lncRNAs in pathological processes of human diseases, especially in carcinogenesis and development. Deregulation of lncRNAs not only alters cellular biological behavior, such as proliferation, migration and invasion, but also represents the poor clinical outcomes. Zinc finger E-box binding homeobox 1 antisense 1 (ZEB1-AS1), an outstanding cancer-related lncRNA, is identified as an oncogenic regulator in diverse malignancies. Dysregulation of ZEB1-AS1 has been demonstrated to exhibit a pivotal role in tumorigenesis and progression, suggesting its potential clinical value as a promising biomarker or therapeutic target for cancers. In this review, we make a summary on the current findings regarding the biological functions, underlying mechanisms and clinical significance of ZEB1-AS1 in cancer progression.

mRNA, microRNA and lncRNA as novel bladder tumor markers

Early detection of bladder cancer (BC) is essential for improvement of the patient's prognosis and general survival rates. Current diagnostic methods are still limited, so new specific and cost-effective biomarkers are emerging as the noninvasive tools in treatment decisions in recurrent BC. Gene expression and epigenetic profile can be analysed using quantitative real-time-PCR (qRT-PCR) method in urine, blood and tissue. This review provides an update of recent findings on BC molecular profile as novel markers in diagnosis and prognosis of bladder tumors. We describe mRNA-, microRNA- and lncRNA-based biomarkers involved in the BC detection, diagnosis, prediction of recurrence and monitoring after treatment.

Long noncoding RNA ZEB1-AS1 predicts an unfavorable prognosis of non-small lung cancer and regulates epithelial to mesenchymal transition through reducing ZEB1 expression

Long non-coding RNAs (lncRNAs) are critical gene regulators with important roles in a wide variety of biological processes, including tumorigenesis. ZEB1-AS1 was significantly increased in NSCLC tissues and cell lines, and its expression levels were highly associated with aggressive tumor progression and poor prognosis. Down-regulation of ZEB1-AS1 suppresses NSCLC cell proliferation and invasion in vitro, as well as inhibits xenograft tumor growth in vivo. Mechanistically, we found that ZEB1-AS1 down-regulation effectively suppressed EMT process through reducing ZEB1 expression, and the ectopic expression of ZEB1 restored the migratory and invasive abilities of NSCLC cells inhibited by ZEB1-AS1 down-regulation. In conclusion, these findings revealed that ZEB1-AS1 plays regulatory roles in NSCLC and it might become a novel molecular indicator of prognosis and therapeutic target in NSCLC.

Long noncoding RNA ZEB1-AS1 expression predicts progression and poor prognosis of colorectal cancer

BACKGROUND

ZEB1-AS1 acts as an oncogene in hepatocellular carcinoma, accelerating tumor growth and promoting metastasis. However, its roles in colorectal cancer (CRC) remain unclear.

METHODS

In this study, we determined the expression of ZEB1-AS1 in CRC tissues by quantitative real-time polymerase chain reaction (qRT-PCR). Additionally, we investigated the relationship between various clinicopathological features of CRC patients and ZEB1-AS1 expression, and evaluated the diagnostic and prognostic value of ZEB1-AS1 in CRC.

RESULTS

We found that ZEB1-AS1 expression was significantly higher in CRC tissues than in adjacent normal colorectal tissues. Moreover, its expression was significantly correlated with tumor size, differentiation degree, TNM grade, metastasis, depth of invasion and Dukes' classification, but not with sex, age, location and organization. In addition, at the optimal cutoff value of 2.340, the values of diagnostic sensitivity and specificity amounted to 63.0% and 90.7%, respectively, with an area under the curve (AUC) of 0.846 (95% CI, 0.797-0.895). Finally, CRC patients of the high ZEB1-AS1 expression group had a poorer prognosis and a significantly lower survival rate than those of the low expression group, and Cox regression analysis indicated that ZEB1-AS1 expression and metastasis were independent predictors of poor prognosis.

CONCLUSIONS

Our data suggest that ZEB1-AS1 has no obvious early diagnostic value, but it may be utilized as a new prognostic biomarker for CRC.

The role of lncRNA MALAT1 in intervertebral degenerative disc disease

Intervertebral degenerative disc disease (IDDD) is a common disease in clinic that causes pain and heavy financial burden on patients with poor prognosis. However, the pathogenesis of IDDD is not clear. Long non-coding RNA (LncRNA) is involved in regulating various body growth and pathological processes by affecting cell proliferation, differentiation, and apoptosis. However, the role of lncRNAs in IDDD is rarely reported. This study aims to investigate the role and mechanism of lncRNA MALAT1 in the development of IDDD. The nucleus pulposus of the intervertebral disc were collected and the primary nucleus pulposus cells were isolated and cultured. The cells were divided into three groups, including IDDD group, empty plasmid group transfected by pcDNA3.1, or MALAT1 group transfected by pcDNA3.1-MALAT1. MALAT1 expression was detected by real-time PCR. Cell proliferation was assessed by MTT assay. Caspase 3 activity was tested by the activity detection kit. IL-1 and IL-6 levels were analyzed by ELISA. The expression of MALAT1 in IDDD nucleus pulposus cells was significantly lower than that in control group (P < 0.05). The expression of MALAT1 was significantly increased after transfection with pcDNA3.1-MALAT1 plasmid in IDDD nucleus pulposus cells, which obviously inhibited cell proliferation, enhanced Caspase 3 activity, and promoted the secretion of IL-1 and IL-6 compared with IDDD group (P < 0.05). MALAT1 level decreased in IDDD nucleus pulposus cells. Upregulation of MALAT1 expression restrained IDDD through suppressing inflammation; inhibiting nucleus pulposus cell apoptosis, and promoting cell proliferation.

Long non-coding RNA HNF1A-AS1 promotes proliferation and suppresses apoptosis of bladder cancer cells through upregulating Bcl-2

Emerging evidences have indicated that long non-coding RNAs (lncRNAs) are pivotal regulators of tumor development and progression. HNF1A-AS1 (HNF1A antisense RNA 1, C12 or f27) is a novel long non-coding RNA that acts as a potential biomarker and is involved in development and progression of several cancers. Nevertheless, we know nothing about the clinical significance and molecular mechanism of HNF1A-AS1 in bladder cancer. In this study, we found that HNF1A-AS1 is significantly up-regulated in bladder cancer. Further experiments had demonstrated that silencing HNF1A-AS1 in bladder cancer cells could inhibit the proliferation and induce apoptosis. Mechanistically, we found down-regulated of HNF1A-AS1 increased the expression of miR-30b-5p and subsequently inhibited the expression of Bcl-2, in a ceRNA-dependent way. Moreover, knockdown of miR-30b-5p reversed cell proliferation inhibition and cell apoptosis induced by silencing HNF1A-AS1. In conclusions, we demonstrated that HNF1A-AS1 plays an important regulatory role in bladder cancer and shed new light on lncRNA-directed diagnostic and therapeutics in bladder cancer.