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

lncRNA Biomarkers of Glioblastoma Multiforme

Long noncoding RNAs (lncRNAs) are RNA molecules of 200 nucleotides or more in length that are not translated into proteins. Their expression is tissue-specific, with the vast majority involved in the regulation of cellular processes and functions. Many human diseases, including cancer, have been shown to be associated with deregulated lncRNAs, rendering them potential therapeutic targets and biomarkers for differential diagnosis. The expression of lncRNAs in the nervous system varies in different cell types, implicated in mechanisms of neurons and glia, with effects on the development and functioning of the brain. Reports have also shown a link between changes in lncRNA molecules and the etiopathogenesis of brain neoplasia, including glioblastoma multiforme (GBM). GBM is an aggressive variant of brain cancer with an unfavourable prognosis and a median survival of 14-16 months. It is considered a brain-specific disease with the highly invasive malignant cells spreading throughout the neural tissue, impeding the complete resection, and leading to post-surgery recurrences, which are the prime cause of mortality. The early diagnosis of GBM could improve the treatment and extend survival, with the lncRNA profiling of biological fluids promising the detection of neoplastic changes at their initial stages and more effective therapeutic interventions. This review presents a systematic overview of GBM-associated deregulation of lncRNAs with a focus on lncRNA fingerprints in patients' blood.

Research on Function of Exosome of miR-328-3p Secreted by Bone Marrow Mesenchymal Stem Cells (BMSCs) on Restraining the Gastric Cancer Through Being Down-Regulated with Trefoil Factor 3

Certain progress has been made in the therapeutic method against gastric cancer such as surgical operation combined with chemotherapy and radiation therapy in recent years. But the therapeutic efficacy and prognosis on gastric cancer was still not satisfactory. The function of exosome of miR-328–3p secreted by bone marrow stromal cells (BMSCs) on restraining the gastric cancer was studied in the present study. The BMSCs with highly-expressed miR-328-3p was established. The exosome in cell supernatant was collected. The exosome of BMSCs and MSCs with highlyexpressed miR-328-3p was added into SGC-7901 cells followed by analysis of miR-328-3p level by Real-time PCR and TFF3 (Trefoil Factor 3) level in exosome by Western blot, cell proliferation, expression of E-cadherin, Vimentin and Caspase-3. miR-328-39 expression was reduced and TFF3 was elevated in gastric cancer tissue (P < 0.05). miR-328-3p was upregulated and TFF3 was downregulated after addition of BMSCs exosomes along with increased cell proliferation and reduced E-cadherin and Caspase3 expression (P < 0.05). In conclusion, exosome of BMSCs could be regulated by miR-328-3p and TFF3 expression is restrained so as to regulate the biological behaviors of gastric cancer cell.

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.

Oncogenic functions of ZEB1 in pediatric solid cancers: interplays with microRNAs and long noncoding RNAs

The transcription factor Zinc finger E-box binding 1 (ZEB1) displays a range of regulatory activities in cell function and embryonic development, including driving epithelial-mesenchymal transition. Several aspects of ZEB1 function can be regulated by its functional interactions with noncoding RNA types, namely microRNAs (miRNAs) and long noncoding RNAs (lncRNAs). Increasing evidence indicates that ZEB1 importantly influences cancer initiation, tumor progression, metastasis, and resistance to treatment. Cancer is the main disease-related cause of death in children and adolescents. Although the role of ZEB1 in pediatric cancer is still poorly understood, emerging findings have shown that it is expressed and regulates childhood solid tumors including osteosarcoma, retinoblastoma, neuroblastoma, and central nervous system tumors. Here, we review the evidence supporting a role for ZEB1, and its interplays with miRNAs and lncRNAs, in pediatric cancers.

Zinc Finger E-Box Binding Homeobox 1 Regulates the Biological Behavior of Glioma Cells via iNOS/NF-κB Signaling

The gliomas pathogenesis is complex and effective molecular targets are still unclear. ZEB1 regulates epithelial mesenchymal transition (EMT) and participates in tumors. Our study intends to analyze ZEB1’s role in glioma cells. qRT-PCR detected ZEB1 mRNA expression in normal group and tumor group. ZEB1 siRNA was transfected into glioma cells followed by measuring ZEB1, E-cadherin and Vimentin expression, cell proliferation, Capase-3 activity as well as NF-κB and iNOS changes by immunoblotting. Upregulation of ZEB1 was found in glioma tumor tissue and correlated with glioma clinicopathological characteristics. Interfering with ZEB1 by siRNA significantly down-regulated ZEB1, inhibited cell proliferation, increased Capase-3 activity, down regulated NF-κB and iNOS proteins in glioma cells, elevated E-cadherin and decreased Vimentin level (P <0.05). ZEB1 down regulation in glioma cells can change the expression of NF-κB/iNOS, regulate cell apoptosis and inhibit cell proliferation, thereby delaying EMT process.

Roles of E-cadherin and Noncoding RNAs in the Epithelial-mesenchymal Transition and Progression in Gastric Cancer

The epithelial–mesenchymal transition (EMT) is thought to be at the root of invasive and metastatic cancer cell spreading. E-cadherin is an important player in this process, which forms the structures that establish and maintain cell–cell interactions. A partial or complete loss of E-cadherin expression in the EMT is presumably mediated by mechanisms that block the expression of E-cadherin regulators and involve the E-cadherin-associated transcription factors. The protein is involved in several oncogenic signaling pathways, such as the Wnt/β-catenin, Rho GTPase, and EGF/EGFR, whereby it plays a role in many tumors, including gastric cancer. Such noncoding transcripts as microRNAs and long noncoding RNAs—critical components of epigenetic control of gene expression in carcinogenesis—contribute to regulation of the E-cadherin function by acting directly or through numerous factors controlling transcription of its gene, and thus affecting not only cancer cell proliferation and metastasis, but also the EMT. This review focuses on the role of E-cadherin and the non-coding RNAs-mediated mechanisms of its expressional control in the EMT during stomach carcinogenesis.

Long Noncoding RNA and Epithelial Mesenchymal Transition in Cancer

Epithelial-mesenchymal transition (EMT) is a multistep process that allows epithelial cells to acquire mesenchymal properties. Fundamental in the early stages of embryonic development, this process is aberrantly activated in aggressive cancerous cells to gain motility and invasion capacity, thus promoting metastatic phenotypes. For this reason, EMT is a central topic in cancer research and its regulation by a plethora of mechanisms has been reported. Recently, genomic sequencing and functional genomic studies deepened our knowledge on the fundamental regulatory role of noncoding DNA. A large part of the genome is transcribed in an impressive number of noncoding RNAs. Among these, long noncoding RNAs (lncRNAs) have been reported to control several biological processes affecting gene expression at multiple levels from transcription to protein localization and stability. Up to now, more than 8000 lncRNAs were discovered as selectively expressed in cancer cells. Their elevated number and high expression specificity candidate these molecules as a valuable source of biomarkers and potential therapeutic targets. Rising evidence currently highlights a relevant function of lncRNAs on EMT regulation defining a new layer of involvement of these molecules in cancer biology. In this review we aim to summarize the findings on the role of lncRNAs on EMT regulation and to discuss their prospective potential value as biomarkers and therapeutic targets in cancer.

Regulation of Proliferation and Epithelial-to-Mesenchymal Transition (EMT) of Gastric Cancer by ZEB1 via Modulating Wnt5a and Related Mechanisms

Background

As a member of the zinc-finger E-box binding protein (ZEB) family, ZEB1 can modulate onset and progression of various tumors, but its regulatory effect or mechanism in GC has not been defined.

Material/Methods

GC tumor tissues and adjacent tissues were collected from GC patients across different TNM stages. Real-time PCR was used to measure ZEB1 expression to analyze its correlation with pathological features of tumors. Cultured GC cell lines SGC-7901 and MGC-803 were randomly assigned into control group, scramble group, and ZEB1 siRNA group. Real-time PCR was employed to analyze ZEB1 expression, and MTT approach was used to measure cell proliferation. Cell apoptosis was evaluated by flow cytometry. Wound healing assay was used to detect its effect on cell migration. Expression of E-cadherin and Vimentin involved in epithelial-to-mesenchymal transition (EMT) was measured by Western blot analysis, along with Wnt5a proteins.

Results

GC tissues had upregulation of ZEB1 (P<0.05 compared to adjacent tissues), whose expression level was correlated with differentiation grade, lymph node metastasis, and tumor pathological stage (P<0.05). Transfection of ZEB1 siRNA into SGC-7901 or MGC-803 cells can suppress ZEB1 expression, inhibit tumor cell proliferation, enhance apoptosis, and inhibit cell migration. Transfected GC cells had higher E-cadherin expression and decreased Vimentin expression or Wnt5a expression (P<0.05 compared to the control group).

Conclusions

ZEB1 expression is increased in GC tumor tissues and is associated with pathological features. The downregulation of ZEB1 can facilitate cell apoptosis via mediating Wnt5a, further suppressing GC cell proliferation and migration, and reducing EMT occurrence.

Regulation of Proliferation and Epithelial-to-Mesenchymal Transition (EMT) of Gastric Cancer by ZEB1 via Modulating Wnt5a and Related Mechanisms

BACKGROUND As a member of the zinc-finger E-box binding protein (ZEB) family, ZEB1 can modulate onset and progression of various tumors, but its regulatory effect or mechanism in GC has not been defined. MATERIAL AND METHODS GC tumor tissues and adjacent tissues were collected from GC patients across different TNM stages. Real-time PCR was used to measure ZEB1 expression to analyze its correlation with pathological features of tumors. Cultured GC cell lines SGC-7901 and MGC-803 were randomly assigned into control group, scramble group, and ZEB1 siRNA group. Real-time PCR was employed to analyze ZEB1 expression, and MTT approach was used to measure cell proliferation. Cell apoptosis was evaluated by flow cytometry. Wound healing assay was used to detect its effect on cell migration. Expression of E-cadherin and Vimentin involved in epithelial-to-mesenchymal transition (EMT) was measured by Western blot analysis, along with Wnt5a proteins. RESULTS GC tissues had upregulation of ZEB1 (P<0.05 compared to adjacent tissues), whose expression level was correlated with differentiation grade, lymph node metastasis, and tumor pathological stage (P<0.05). Transfection of ZEB1 siRNA into SGC-7901 or MGC-803 cells can suppress ZEB1 expression, inhibit tumor cell proliferation, enhance apoptosis, and inhibit cell migration. Transfected GC cells had higher E-cadherin expression and decreased Vimentin expression or Wnt5a expression (P<0.05 compared to the control group). CONCLUSIONS ZEB1 expression is increased in GC tumor tissues and is associated with pathological features. The downregulation of ZEB1 can facilitate cell apoptosis via mediating Wnt5a, further suppressing GC cell proliferation and migration, and reducing EMT occurrence.

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.

Long Noncoding RNAs Serve as Potential Diagnostic Biomarkers for Colorectal Cancer

Background: Mounting evidence has indicated that long noncoding RNAs (lncRNAs) are promising candidates for tumor diagnosis and prognosis. Nonetheless, the significance of lncRNAs in colorectal cancer (CRC) diagnosis remains to be clarified. Here, we performed a comprehensive meta-analysis to evaluate the utility of lncRNAs as diagnostic indicators for CRC. Materials and Methods: Pertinent studies were searched using PubMed, PMC, Web of Science, Cochrane, and EMBASE database up to September 2018. Study quality was assessed with the Quality Assessment for Studies of Diagnostic Accuracy-2. Subgroup analyses by sample size and publication year were conducted. Threshold effect and meta-regression were performed to find the origin of heterogeneity. Statistical analyses were conducted using Stata and Meta-Disc. Results: A total of 19 studies with 3,114 individuals were enrolled in the current analysis. The overall sensitivity and specificity of lncRNAs in the diagnosis of CRC were 0.83 [95% confidence interval (CI): 0.76-0.87] and 0.84 (95% CI: 0.77-0.89), respectively. The pooled positive likelihood ratio was 5.11 (95% CI: 3.57-7.31), and the pooled negative likelihood ratio was 0.21 (95% CI: 0.15-0.28). The overall area under the curve was 0.90 (95% CI: 0.87-0.92), with a diagnostic odds ratio of 24.57 (95% CI: 14.67-41.17). Conclusions: The accuracy of lncRNAs for CRC diagnosis is high, and lncRNAs could be functioned as promising candidates for CRC diagnosis.

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.