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Aims: Glioblastoma (GBM) is the most common and aggressive intracranial tumor with poor prognosis. A large majority of clinical chemotherapeutic agents cannot achieve the desired therapeutic effect. Chelerythrine (CHE), a natural component with multitudinous pharmacological functions, has been proven to have outstanding antitumor effects in addition to antibacterial, anti-inflammatory, and hypotensive effects. However, the anti-GBM effect of CHE has not been reported to date. The purpose of this paper is to observe the anti-GBM effect of CHE and further explore the related mechanism., Materials and Methods: GBM cell lines (U251 and T98G) and BALB/c nude mice were used in the experiments. Methyl thiazolyl tetrazolium (MTT) and clone formation assays were applied to detect the viability, proliferation and stemness of GBM cells. Flow cytometry was utilized to identify the effect of CHE on GBM apoptosis. Scratch and Transwell experiments reflected the migration and invasion of cells. In vivo, xenograft tumors were implanted subcutaneously in nude mice. The progression of tumors was assessed by ultrasound and magnetic resonance imaging. Finally, western blot, bioinformatics, and immunohistochemistry experiments were used to explore the molecular mechanisms in depth., Key Findings: In vitro tests showed that CHE inhibited the proliferation, stemness, migration, and invasion of GBM cells and induced apoptosis. In vitro, CHE was observed to restrain the progression of xenograft tumors. We eventually proved that the cytotoxicity of CHE was relevant to the TGFB1-ERK1/2/Smad2/3-Snail/ZEB1 signaling pathway., Significance: CHE inhibited GBM progression by inhibiting the TGFB1-ERK1/2/Smad2/3-Snail/ZEB1 signaling pathway and is a potential chemotherapeutic drug for GBM., (Copyright © 2022 Elsevier Inc. All rights reserved.)

Prostate cancer (PCa) is the second most prevalent cancer in men worldwide. Most cases of death from PCa are due to metastasis. Early stages of metastasis are mediated by epithelial-mesenchymal transition (EMT) process through which cancer cells acquire motility and invasive characteristics. Thus, more potent and novel therapeutic strategies must be designed based on the inhibition of EMT or metastasis. Herein, we employ a co-culture system to evaluate the anti-EMT effects of human amniotic mesenchymal stromal cells (hAMSCs) on LNCaP PCa cells. The RNA of treated (sample) and untreated cancer cells (control) and whole-cell lysates of related cells were prepared and analysed through quantitative real-time polymerase chain reaction (qRT-PCR) and western blot, respectively. Based on the results, the expression of vimentin, Snail and Zeb1 in LNCaP cells decreased and the expression of E-cadherin increased after treatment with hAMSCs. Furthermore, induction of the cellular apoptosis in LNCaP cells was detected. The anti-cancer activity of conditioned medium from hAMSCs was shown using hanging drop technique (a 3D cell culture model). Our findings support the idea that stem cells can be considered as a novel therapeutic approach to inhibit prostate cancer cells. SIGNIFICANCE OF THE STUDY: The anti-tumour activity of hAMSCs on LNCaP prostate cancer cells using 2D and 3D cell culture models via induction of apoptosis, suppression of EMT process and down-regulation of EGFR was shown. The results of the present study support this idea that hAMSCs may be a potent therapeutic tool to suppress tumour growth in LNCaP prostate cancer cells., (© 2021 John Wiley & Sons Ltd.)

Prostate cancer (PCa) is the second most diagnosed type of cancer in men worldwide. Advanced PCa is resistant to conventional therapies and high recurrence has been associated with high rates of metastasis. Cancer stem cells (CSCs) have been proposed to be responsible for this, due to their ability of self‑renewal and differentiation into other cell types. Zinc finger E‑box‑binding homeobox 1 (ZEB1), a transcription factor involved in the regulation of epithelial‑mesenchymal transition (EMT), has been associated with the activation of several mechanisms that lead to resistance to treatment. As recent evidence has shown that CSCs may originate from non‑CSCs during EMT, it was hypothesized that knocking down ZEB1 expression in PCa cell lines could revert some properties associated with CSCs. Using lentiviraltransduction, ZEB1 expression was silenced in the PCa DU145 and LNCaP cell lines. The mRNA and protein expression levels of key canonical CSC markers (Krüppel‑like factor 4, SOX2, CD44 and CD133) were determined using reverse transcription‑-quantitative PCR and western blot analysis, respectively. In addition, the colony forming ability of the ZEB1‑knockdown cells was evaluated, and the type of colonies formed (holoclones, paraclones and meroclones) was also characterized. Finally, the ability to form prostatospheres was evaluated in vitro . It was found that in ZEB1‑knockdown DU145 cells, the expression levels of CSC phenotype markers (CD44, CD133 and SOX2) were decreased compared with those in the control group. Furthermore, ZEB1‑knockdown cells exhibited a lower ability to form prostatospheres and to generate colonies. In conclusion, stable silencing of ZEB1 reversed CSC properties in PCa cell lines. Since ZEB1 is associated with malignancy, therapy resistance and a CSC phenotype in PCa cell lines, targeting ZEB1 may be a key factor to eradicate CSCs and improve the prognosis of patients with advanced PCa.

As a potential drug/gene delivery system, the ultrasound-targeted microbubble destruction (UTMD) system can be used as a vehicle as well as increasing the permeability of biological barriers to enhance the effect of tumor treatment. However, the effect of UTMD in the tumor EMT process is unknown. In this study, we aimed to investigate the potential and mechanism of UTMD induced oxidative stress in inhibiting EMT of breast cancer. Human breast MDA231 cells were treated with microbubble (MB), ultrasound (US) and UTMD, respectively. The generation of oxidative stress, the levels of miR-200c, ZEB1 and vimentin, and the numbers of migratory cells were evaluated quantitatively and qualitatively by the measurement of intracellular reactive oxygen species (ROS), qRT-PCR, western blot assay, and transwell assay. Then, to evaluate the role of UTMD-induced oxidative stress and miR-200c in the epithelial-mesenchymal transition (EMT) inhibition, the ROS scavenger N-acetyl-L-cysteine (NAC) and miR-200c inhibitor were used before UTMD treatment. We found that UTMD induced oxidative stress, upregulated the expression of miR-200c, downregulated the expression of ZEB1 and vimentin and suppressed the MDA231 cell migration. The addition of NAC and miR-200c inhibitor had an opposite impact on the expression of miR-200c and ZEB1, thus hindered the effects of UTMD on MDA231 cells EMT. In conclusion, UTMD can inhibit the EMT characteristics of MDA231 cells. The mechanism may be related to the regulation of the miR-200c/ZEB1 axis through the generation of ROS induced by UTMD, which may provide a new strategy to prevent the tumor cells EMT under UTMD treatment.

Glioblastoma (GBM) responses to bevacizumab are invariably transient with acquired resistance. We profiled paired patient specimens and bevacizumab-resistant xenograft models pre- and post-resistance toward the primary goal of identifying regulators whose targeting could prolong the therapeutic window, and the secondary goal of identifying biomarkers of therapeutic window closure. Bevacizumab-resistant patient specimens and xenografts exhibited decreased vessel density and increased hypoxia versus pre-resistance, suggesting that resistance occurs despite effective therapeutic devascularization. Microarray analysis revealed upregulated mesenchymal genes in resistant tumors correlating with bevacizumab treatment duration and causing three changes enabling resistant tumor growth in hypoxia. First, perivascular invasiveness along remaining blood vessels, which co-opts vessels in a VEGF-independent and neoangiogenesis-independent manner, was upregulated in novel biomimetic 3D bioengineered platforms modeling the bevacizumab-resistant microenvironment. Second, tumor-initiating stem cells housed in the perivascular niche close to remaining blood vessels were enriched. Third, metabolic reprogramming assessed through real-time bioenergetic measurement and metabolomics upregulated glycolysis and suppressed oxidative phosphorylation. Single-cell sequencing of bevacizumab-resistant patient GBMs confirmed upregulated mesenchymal genes, particularly glycoprotein YKL-40 and transcription factor ZEB1, in later clones, implicating these changes as treatment-induced. Serum YKL-40 was elevated in bevacizumab-resistant versus bevacizumab-naïve patients. CRISPR and pharmacologic targeting of ZEB1 with honokiol reversed the mesenchymal gene expression and associated stem cell, invasion, and metabolic changes defining resistance. Honokiol caused greater cell death in bevacizumab-resistant than bevacizumab-responsive tumor cells, with surviving cells losing mesenchymal morphology. Employing YKL-40 as a resistance biomarker and ZEB1 as a target to prevent resistance could fulfill the promise of antiangiogenic therapy. SIGNIFICANCE: Bevacizumab resistance in GBM is associated with mesenchymal/glycolytic shifts involving YKL-40 and ZEB1. Targeting ZEB1 reduces bevacizumab-resistant GBM phenotypes. GRAPHICAL ABSTRACT: http://cancerres.aacrjournals.org/content/canres/80/7/1498/F1.large.jpg., (©2020 American Association for Cancer Research.)

Purpose/Aim: More and more evidences suggest that airway remodeling of fibrotic lung diseases may be associated with epithelial-mesenchymal transition (EMT) of human A549 cells induced by transforming growth factor (TGF)-β1. Schisandrin B (Sch B) is the highest content of dibenzocyclooctadiene lignans in Schisandra chinensis. In this study, we assessed the inhibitory influences of Sch B on TGF-β1-stimulated EMT in human A549 cells. Materials and Methods: The influences of Sch B on cell viability, invasion and metastasis in TGF-β1-induced human A549 cells were detected by MTT, wound healing and transwell invasion assays. The expression levels of α-SMA, E-cadherin, ZEB1 and Twist1 were examined by quantitative reverse transcription polymerase chain reaction (qRT-PCR) and western blot. The enrichment of H3K4me3 and H3K9me3 at the ZEB1 promoter was determined by ChIP analysis. Results: Experimental results showed that Sch B increased the expression of the epithelial phenotype marker E-cadherin and inhibited the expression of the mesenchymal phenotype marker α-SMA during EMT induced by TGF-β1. The enhancement in invasion and migration of TGF-β1-induced A549 cells was inhibited by Sch B. Sch B also repressed the expression of ZEB1 transcription factor in EMT, by increasing the enrichment of H3K9me3 at the ZEB1 promoter to repress its transcription while the expression of the Twist1 transcription factor was unaffected. Conclusions: Our data suggest that Sch B can prevent TGF-β1-stimulated EMT in A549 cells through epigenetic silencing of ZEB1, which may be clinically related to the efficient treatment of EMT-associated fibrotic diseases.

Osteosarcoma (OS) patients often exhibit pulmonary metastasis, which results in high patient mortality. Our present study established the doxorubicin (Dox) resistant human OS MG-63 and HOS cells and named them MG-63/Dox and HOS/Dox, respectively. The Dox resistant OS cells had greater invasion ability than that of parental cells. The expression of ZEB1, while not FOXM1, Snail, HIF-1α, or Sp1, was significantly increased in Dox resistant OS cells. Silencing of ZEB1 can attenuate the metastasis and increase Dox sensitivity of MG-63/Dox and HOS/Dox cells. The upregulation of ZEB1 can increase of the expression of interlukin-6 (IL-6). Anti-IL-6 inhibited the invasion and increase the Dox sensitivity of MG-63/Dox and HOS/Dox cells. There was no significant difference of ZEB1 mRNA between Dox resistant and control cells. The upregulation of ZEB1 in Dox resistant OS cells can be attributed to the increase of protein half-life. This was confirmed by results that the inhibitor of proteasomal degradation can increase ZEB1 in Dox resistant OS cells. Over expression of SIAH1 can inhibit the expression of ZEB1 and increase the Dox sensitivity of MG-63/Dox and HOS/Dox cells. Collectively, we confirmed that SIAH1 induced ZEB1 is involved in the Dox resistance of OS cells.

Background: Radiotherapy is one of the main treatment options for non-metastatic prostate cancer (PCa). Although treatment technical optimization has greatly improved local tumor control, a considerable fraction of patients still experience relapse due to the development of resistance. Radioresistance is a complex and still poorly understood phenomenon involving the deregulation of a variety of signaling pathways as a consequence of several genetic and epigenetic abnormalities. In this context, cumulative evidence supports a functional role of microRNAs in affecting radioresistance, suggesting the modulation of their expression as a novel radiosensitizing approach. Here, we investigated for the first time the ability of miR-205 to enhance the radiation response of PCa models., Methods: miR-205 reconstitution by a miRNA mimic in PCa cell lines (DU145 and PC-3) was used to elucidate miR-205 biological role. Radiation response in miRNA-reconstituted and control cells was assessed by clonogenic assay, immunofluorescence-based detection of nuclear γ-H2AX foci and comet assay. RNAi was used to silence the miRNA targets PKCε or ZEB1. In addition, target-protection experiments were carried out using a custom oligonucleotide designed to physically disrupt the pairing between the miR-205 and PKCε. For in vivo experiments, xenografts generated in SCID mice by implanting DU145 cells stably expressing miR-205 were exposed to 5-Gy single dose irradiation using an image-guided animal micro-irradiator., Results: miR-205 reconstitution was able to significantly enhance the radiation response of prostate cancer cell lines and xenografts through the impairment of radiation-induced DNA damage repair, as a consequence of PKCε and ZEB1 inhibition. Indeed, phenocopy experiments based on knock-down of either PKCε or ZEB1 reproduced miR-205 radiosensitizing effect, hence confirming a functional role of both targets in the process. At the molecular level, miR-205-induced suppression of PKCε counteracted radioresistance through the impairment of EGFR nuclear translocation and the consequent DNA-PK activation. Consistently, disruption of miR-205-PKCε 3'UTR pairing almost completely abrogated the radiosensitizing effect., Conclusions: Our results uncovered the molecular and cellular mechanisms underlying the radiosensitizing effect of miR-205. These findings support the clinical interest in developing a novel therapeutic approach based on miR-205 reconstitution to increase PCa response to radiotherapy.

Objective: To explore the role of hsa-microRNA-99b/let-7e/microRNA-125a cluster in the progression of liver cancer and its possible regulatory mechanisms., Patients and Methods: Ten liver cancer tissues were randomly selected and matched with normal liver tissue samples. The mRNA expression levels of miR-99b, let-7e and miR-125a were detected by Real Time-quantitative Polymerase Chain Reaction (RT-qPCR). The three miRNA mimics were transfected alone or together into hepatoma cells SMMC-7721; at the same time, the knockdown of the three miRNAs was also performed. Then the cell invasive and migratory abilities were examined through transwell assay. Bioinformatics analysis was used to detect the potential transcription factors that bind to the hsa-microRNA-99b/let-7e/microRNA-125a promoter sequence, and the binding of the two was verified by the Luciferase reporting assay. The level of hsa-microRNA-99b/let-7e/microRNA-125a mature mRNA was detected after ZEB1 was inhibited by ZEB1 siRNA. Meanwhile, after interfering with Drosha and ZEB1, the expression level of hsa-microRNA-99b/let-7e/microRNA-125a of the primary transcript was examined. Rescue experiments were carried out to assess the role of hsa-microRNA-99b/let-7e/microRNA-125a in the ZEB1 regulation of invasive cell capacity., Results: The mRNA levels of microRNA-99b, let-7e, and microRNA-125a in 10 selected hepatocarcinoma tissues were significantly higher than those in the matched paracancerous tissues. After overexpressing the three miRNA mimics either alone or together, cell invasive and migratory abilities were extensively enhanced, and vice versa. It was found that there is a binding site in the upstream sequence of the promoter region of the hsa-microRNA-99b/let-7e/microRNA-125a cluster for ZEB1. The Luciferase reporter gene results showed an increase in the Luciferase activity of the cells transfected with E-box element wild-type sequence, while mutant E-box element group did not change. After knocking out ZEB1, the levels of mature microRNA-99b, let-7e and microRNA-125a were reduced. However, when DROSHA was knocked out, the levels of immature microRNA-99b, let-7e and microRNA-125a were increased, while simultaneous knocking out ZEB1 reversed this effect. Besides, the invasive ability of SMMC-7721 cells decreased after KEB1 was knocked down, while the opposite result was observed after transfection of hsa-microRNA-99b/let-7e/microRNA-125a alone or together., Conclusions: Hsa-microRNA-99b/let-7e/microRNA-125a cluster is highly-expressed in hepatocarcinoma, and its expression can be regulated by ZEB1. In addition, the overexpression of this cluster can promote the invasion of liver cancer cells and advance liver cancer progression.

Objective: In order to investigate the role of the zinc finger E-box-binding homeobox 1 (ZEB1) expression in the incidence of non-small cell lung cancer (NSCLC), the effects of the ZEB1 expression on the pathogenesis and prognosis of NSCLC were investigated., Patients and Methods: Correlations of the expression of ZEB1 in 88 clinical patients with NSCLC with clinicopathological features were determined. The patients were followed up for 60 months to study the correlation between the ZEB1 expression and the prognosis of NSCLC patients. To further explore the role of the ZEB1 expression in the incidence of NSCLC, the expressions of ZEB1 and E-cadherin in three NSCLC cell lines (A549, NCI-H1299 and NCI-H1975) and human normal lung epithelial BESA-2B cell line were measured, and the cell invasion ability was detected. The role of ZEB1 in NSCLC cell invasion was verified through the knockdown of ZEB1 by the short hairpin ribonucleic acids (shRNAs). In addition, its effects on the proliferation and apoptosis of NSCLC cells were confirmed by the overexpression of ZEB1., Results: The expression of ZEB1 in NSCLC tissues was remarkably higher than that in normal tissues, and the expression level of ZEB1 was significantly related to the cancer stage and tumor size. The lower the expression of ZEB1 was, the higher the overall survival rate and the longer the survival time would be. The expression of ZEB1 was negatively correlated with that of E-cadherin in cell lines, and ZEB1-shRNAs markedly reduced the invasion ability of NSCLC cells. The overexpression of ZEB1 resulted in an increase in the proliferation activity and a significant decrease in the apoptosis of A549 cells., Conclusions: The expression of ZEB1 is closely related to the incidence and prognosis of NSCLC. Increased expression of ZEB1 is helpful for promoting the invasion of NSCLC and enhancing the proliferation activity of NSCLC.

Aim: To investigate whether long non-coding RNA (lncRNA) ZEB1 antisense 1 (ZEB1-AS1) affects cell migration and invasion of cervical cancer by regulating epithelial-mesenchymal transition (EMT) via the p38MAPK pathway., Methods: Human cervical cancer cell line Hela was classified into Control, NC siRNA, ZEB1-AS1 siRNA, SB203580 (p38MAPK pathway inhibitor) and ZEB1-AS1 siRNA + Anisomycin (p38MAPK pathway activator) groups. Quantitative real-time polymerase chain reaction was performed for ZEB1-AS1 expression, Western blotting to measure p38MAPK signaling pathway-/EMT-related proteins, and Wound-healing and Transwell assays to evaluate cell migration and invasion respectively., Results: ZEB1-AS1 was upregulated in cancer tissues and related to major clinicopathological features of cervical cancer. Besides, patients with lower-ZEB1-AS1-expression had a higher 5-year survival rate than those patients with higher-ZEB1-AS1-expression. High ZEB1-AS1 expression and advanced Federation of Gynecology and Obstetrics stage were independent risk factors for patients' prognosis. Both ZEB1-AS1 siRNA and SB203580 effectively reduced p-p38 expression and the migration and invasion of Hela cells, with elevation of E-cadherin and reduction of Vimentin and N-cadherin. However, inhibitory effects of ZEB1-AS1 siRNA on EMT as well as cell migration and invasion of the Hela cell were reversed by Anisomycin., Conclusion: Inhibition of ZEB1-AS1 can block the p38MAPK signaling pathway, ultimately restricting the EMT and suppressing cell migration and invasion of cervical cancer cells., (© 2018 S. Karger AG, Basel.)

Mammalian palate separates the oral and nasal cavities for normal feeding, breathing and speech. The palatal shelves are a pair of maxillary prominences that consist of the neural crest-derived mesenchyme and surrounding epithelium. Palatogenesis is completed by the fusion of the midline epithelial seam (MES) after the medial edge epithelium (MEE) cells make contact between the palatal shelves. Various cellular and molecular events, such as apoptosis, cell proliferation, cell migration, and epithelial-mesenchymal transition (EMT), are involved in palatogenesis. The Zeb family of transcription factors is an essential player during normal embryonic development. The distinct role of the Zeb family has not been thoroughly elucidated to date. In mouse palate, the Zeb family factors are expressed in the palatal mesenchyme until MEE contact. Interestingly, the expression of the Zeb family has also been observed in MES, which is already fused with the mesenchymal region. The regulatory roles of the Zeb family in palatogenesis have not been elucidated to date. The purpose of this study is to determine the Zeb family effects on the cellular events. To investigate the functions of the Zeb family, siRNA targeting Zeb family was used to treat in vitro organ culture for temporary inhibition of the Zeb family during palatogenesis. In the cultured palate containing siRNA, MES was clearly observed, and E-cadherin, an epithelial marker, was still expressed. Inhibition of the Zeb family results in the suppression of apoptosis, increased cell proliferation, and defective cell migration in the developing palate. Our data suggest that the Zeb family plays multiple roles in the stimulation and inhibition of apoptosis and cell proliferation and efficient mesenchymal cell migration during palatogenesis., (Copyright © 2018 Elsevier Inc. All rights reserved.)

Non-small cell lung cancer (NSCLC) is known as highly metastatic disease because it is difficult to diagnose at early stage. More than 60% of NSCLC patients' overexpress receptor tyrosine kinase (RTK) such as EGFR that has been proved to display resistance to receptor tyrosine kinase inhibitor (TKI) through PI3K signaling, while single PI3K inhibitors increase RTK expression as feedback. So, to select the proper targeted agent or target an assortment of molecular subsets, such as EGFR mutations for different subgroups of patients with NSCLC is urgent. Compound BENC-511, a potent PI3K inhibitor, had effects on inhibiting cancer cell survival and delaying tumor growth, but the effects and mechanisms on cancer metastasis are not clear. Methods of Scratch assay, Transwell system, experimental metastasis mice models, plasmid transfection, quantitative real-time PCR and Western blot were used. Results showed that BENC-511 could significantly inhibit lung cancer cells invasion and metastasis both in vitro and in vivo. And it not only inhibited PI3K/Akt signal pathway, but also directly suppressed phosphorylation of EGFR and nuclear translocation of β-catenin. Moreover, our study firstly reported BENC-511 seemed more sensitive to NSCLC cells that highly expressed Zinc-finger E-box binding protein 1 (ZEB1), one of the epithelial-mesenchymal transition (EMT) inducer, and knockdown of ZEB1 could improve the effects of this compound. These findings suggested that BENC-511 should be a promising lead molecule for anti-metastasis therapy by targeting β-catenin/ZEB1 regulatory loop and serve as a therapeutic agent to inhibit metastasis of NSCLC., (Copyright © 2018 Elsevier B.V. All rights reserved.)

Scientists are increasingly focusing attention on natural products of plant origin for use as agents in cancer protection and treatment. Cyclamen L. tuber extracts contain saponin glycosides that have been shown to have anti-cancer and other biological activities. The epithelial-to-mesenchymal transition (EMT) is thought to enhance malignant tumour progress. The transcriptional repressor zinc-finger E-box binding homeobox 1 (ZEB1) is an important inducer of EMT in different human tumours and has recently been shown to boost invasion by tumour cells. In this study, we investigated the effects of endemic Cyclamen pseudibericum (CP) saponin-rich tuber extract on the capacity of non-small cell lung cancer line A549 cells to proliferate, invade and migrate and also examined the expression levels of several invasion-migration-related microRNAs (miRNAs) to identify those which directly targeted ZEB1. The cytotoxicity effect of the CP extract on the A549 cancer cells was determined by the luminometric method. The half-minimal (50%) inhibitory concentration dose in the A549 cells was determined to be 41.64 ± 2.35 µg/mL. Using the Matrigel invasion chamber system and the wound healing assay we observed that the CP extract suppressed the invasion and migration capacity of A549 cells, respectively. The expression of miRNAs in A549 cells was evaluated by real-time PCR. Our data showed that overexpression of miRNA miR-200c hindered the EMT by increasing the expression of E-cadherin and decreasing the expression of both N-cadherin and vimentin through the direct targeting of ZEB1. These findings suggest that the saponin-rich tuber extract of CP may have considerable anti-cancer properties in lung cancer. Further studies are required to examine in detail the molecular-based mechanism involved in the EMT process of the extract along with isolation and identification of active saponin components.

Long non-coding RNA OIP5-AS1 has been studied in human diseases, including several kinds of cancers. It was not studied or reported in hepatoblastoma, so we chose it to do our research in hepatoblastoma. We thought OIP5-AS1 was oncogenic in hepatoblastoma for the high expression of it in hepatoblastoma tissues and cells. OIP5-AS1 knockdown was carried out in cancer cells. Unsurprisingly, this action was verified to be able to inhibit cell proliferation, metastasis and EMT progress in hepatoblastoma. We then measured the low expression level of miR-186a-5p and the high expression level of ZEB1 in hepatoblastoma tissues and cells. The relevance among them was analyzed by using correlation analysis. In order to prove the ceRNA pattern in this study, nuclear separation experiment, RIP assay and dual luciferase assays were all put into use. We discovered OIP5-AS1 is located in nucleus of cancerous cells. It could target to miR-186a-5p and up-regulate the target gene of miR-186a-5p (ZEB1). Finally, rescue assay was utilized and proved the effect of OIP5-AS1-miR-186a-5p-ZEB1 axis on hepatoblastoma cell activities. Based on all above findings, we came into a conclusion that OIP5-AS1 is a ceRNA in Hepatoblastoma cells through modulating miR-186a-5p/ZEB1., (Copyright © 2018 Elsevier Masson SAS. All rights reserved.)

Investigating stimulation of endogenous wound healing in corneal endothelial cells (CECs) may help address the global shortage of donor corneas by decreasing the number of transplants performed for blindness because of endothelial dysfunction. We previously reported that IL-1β stimulation leads to fibroblast growth factor (FGF2) expression, enhancing migration and proliferation of mammalian CECs. However, FGF2 also promotes the endothelial-mesenchymal transition, which can lead to retrocorneal membrane formation and blindness. This prompted us to investigate downstream FGF2 signaling targets that could be manipulated to prevent retrocorneal membrane formation. FGF2 stimulation altered cell morphology and induced expression of mesenchymal transition marker genes such as snail family transcriptional repressor 1 ( SNAI1 ), SNAI2 , zinc finger E-box-binding homeobox 1 ( ZEB1 ), and ZEB2 This, in turn, induced expression of fibronectin, vimentin, and type I collagen, and suppressed E-cadherin in CECs in vitro and ex vivo siRNA-mediated SNAI1 knockdown revealed that SNAI1 induces ZEB1 expression, in turn inducing expression of type I collagen, the major component of retrocorneal membranes, and of cyclin-dependent kinase 2 (CDK2) and cyclin E1, promoting cell proliferation. siRNA-mediated knockdown of SNAI1 or ZEB1 , but not of CDK2 , inhibited FGF2-dependent expression of fibronectin, vimentin, and type I collagen and of suppression of E-cadherin expression. We conclude that SNAI1 is a key regulator of FGF2-dependent mesenchymal transition in human ex vivo corneal endothelium, with ZEB1 regulating type I collagen expression and CDK2 regulating cell proliferation. These results suggest that SNAI1 promotes fibrosis and cell proliferation in human corneal endothelium through ZEB1 and CDK2., (© 2018 by The American Society for Biochemistry and Molecular Biology, Inc.)

Epithelial-Mesenchymal Transition (EMT) is a biological program that plays key roles in various developmental and pathological processes. Although much work has been done on signaling pathways and transcription factors regulating EMT, the epigenetic regulation of EMT remains not well understood. Histone variants have been recognized as a key group of epigenetic regulators. Among them, macroH2A1 is involved in stem cell reprogramming and cancer progression. We postulated that macroH2A1 may play a role in EMT, a process involving reprogramming of cellular states. In this study, we demonstrate that expression of macroH2A1 is dramatically reduced during EMT induction in immortalized human mammary epithelial cells (HMLE). Moreover, ectopic expression of the macroH2A1.1 isoform, but not macroH2A1.2, can suppress EMT induction and reduce the stem-like cell population in HMLE. Interestingly, macroH2A1.1 overexpression cannot revert stable mesenchymal cells back to the epithelial state, suggesting a stage-specific role of macroH2A1.1 in EMT. We further pinpointed that the function of macroH2A1.1 in EMT suppression is dependent on its ability to bind the NAD + metabolite PAR, in agreement with the inability to suppress EMT by macroH2A1.2, which lacks the PAR binding domain. Thus, our work discovered a previously unrecognized isoform-specific function of macroH2A1 in regulating EMT induction.

The ataxia-telangiectasia-mutated (ATM) and rad3-related (ATR) checkpoint pathway plays an essential role in modulating cellular responses to replication stress and DNA damage to maintain genomic stability. In various tumors, cancer cells have increased dependence on ATR signaling for survival, making ATR a promising target for cancer therapy. ATR inhibitors sensitize multiple tumor cell types to radiation and DNA-damaging agents, but application of an ATR inhibitor alone shows limited efficacy. In the present study, we investigated the role of epithelial-to-mesenchymal transition (EMT) and the EMT transcription factor ZEB1 in regulating cell sensitivity to the ATR inhibitor VE-821. We found that VE-821 induced EMT with concomitant ZEB1 upregulation and promoted migration in cells in which the anti-proliferative effect of VE-821 was limited. Knocking down ZEB1 using siRNA partially reversed VE-821-induced EMT, and sensitized cells to VE-821 via effective attenuation of migration and AKT/ERK signaling. Moreover, ZEB1 inhibition promoted Chk1 phosphorylation and induced S-phase arrest by enhancing TopBP1 expression, which suggests a distinctive modulatory effect of ZEB1 on Chk1. Finally, combining VE-821 with ZEB1 inhibition enhanced DNA damage accumulation. These results demonstrate that EMT represents a novel mechanism for limiting the effectiveness of an ATR inhibitor, and thus suggest that ZEB1 inhibition might represent a new approach to increasing the efficiency of, or reversing resistance to, ATR inhibitors.

Ovarian cancer is one of the deadliest gynecological malignancies in women. Chemoresistance has been a major obstacle for ovarian cancer treatment. Zinc finger E-box-binding homeobox 1 (ZEB1) is an important regulator of tumor development in various types of cancer. Abnormal expression of SLC3A2 (CD98hc), a type 2 transmembrane cell surface molecule, has been described in several cancers. This study was designed to investigate the role of ZEB1 and SLC3A2 in the chemoresistance to cisplatin in ovarian cancer cells. We found that ZEB1 was increased in cisplatin-resistant SKOV3/DPP cells. Downregulation of ZEB1 significantly decreased cell viability in response to cisplatin, increased cis-platin-induced apoptosis, and decreased migration and invasion in the presence of cisplatin. In addition, downregulation of ZEB1 decreased the volume and weight of implanted tumors. SLC3A2 was decreased in cisplatin-resistant SKOV3/DPP cells. Upregulation of SLC3A2 significantly decreased cell viability in response to cisplatin, increased cisplatin-induced apoptosis, and decreased migration and invasion in the presence of cisplatin. Moreover, upregulation of SLC3A2 decreased the volume and weight of implanted tumors. Downregulation of ZEB1 resulted in a significant increase of SLC3A2 expression. Moreover, downregulation of SLC3A2 significantly inhibited ZEB1 knockdown-mediated inhibition of cisplatin-resistance. ZEB1-mediated regulation of SLC3A2 was involved in the chemoresistance to cisplatin in ovarian cancer cells. Overall, we provide new insights into the mechanism of chemoresistance to cisplatin in ovarian cancer cells. ZEB1/SLC3A2 may be promising therapeutic targets for enhancement of the sensitivity of ovarian cancer cells to cisplatin-mediated chemotherapy., (© 2018 S. Karger AG, Basel.)

Background/aims: MicroRNA-142-3p (miR-142-3p) is dysregulated in many malignancies and may function as a tumor suppressor or oncogene in tumorigenesis and tumor development. However, few studies have investigated the clinical significance and biological function of miR-142-3p in hepatocellular carcinoma (HCC)., Methods: The expression levels of taurine upregulated gene 1 (TUG1), miR-142-3p, and zinc finger E-box-binding homeobox 1 (ZEB1) were evaluated in HCC tissues and cell lines by quantitative real-time PCR. MTT and colony formation assays were used to detect cell proliferation ability, transwell assays were used to assess cell migration and invasion, and luciferase reporter assays were used to examine the interaction between the long noncoding RNA TUG1 and miR-142-3p. Tumor formation was evaluated through in vivo experiments., Results: miR-142-3p was significantly downregulated in HCC tissues, but TUG1 was upregulated in HCC tissues. Knockdown of TUG1 and upregulation of miR-142-3p inhibited cell proliferation, cell migration, cell invasion, and the epithelial-mesenchymal transition (EMT). miR-142-3p was found to be a prognostic factor of HCC, and the mechanism by which TUG1 upregulated ZEB1 was via direct binding to miR-142-3p. In vivo assays showed that TUG1 knockdown suppressed cell proliferation and the EMT in nude mice., Conclusion: The results of this study suggest that the TUG1/miR-142-3p/ ZEB1 axis contributes to the formation of malignant behaviors in HCC., (© 2018 The Author(s). Published by S. Karger AG, Basel.)

Background/aims: Long noncoding RNAs (lncRNAs) have been a research hotspot, as they play important roles in tumor development. However, their expression pattern and biological function in osteosarcoma have not yet been clarified., Methods: Differentially expressed lncRNAs in osteosarcoma and paracarcinoma tissues were identified by screening an lncRNA microarray, and candidate lncRNAs were verified by quantitative real-time PCR (qRT-PCR). A series of bioinformatics and molecular biological methods were adopted to investigate the interaction among lncRNA, microRNA (miRNA), and miRNA target genes during the development and occurrence of osteosarcoma. Cell viability was measured using a Cell Counting Kit-8 assay., Results: Chip microarray screening combined with the validation of differentially expressed candidate lncRNAs showed that the lncRNA small nucleolar RNA host gene 16 (SNHG16) had the largest fold change. SNHG16 was highly expressed in osteosarcoma tissues and cell lines, and its downregulation led to the suppressed proliferation of osteosarcoma cells. Further investigations revealed that SNHG16 could upregulate zinc finger E-box-binding homeobox 1 (ZEB1) expression by acting as an endogenous sponge of miR-205. Moreover, rescue assays proved that the effects of SNHG16 on the proliferation of osteosarcoma cells were dependent on miR-205., Conclusion: SNHG16 can significantly enhance the proliferation of osteosarcoma cells. In addition, SNHG16, miR-205, and ZEB1 interact in a common pathway during the development and occurrence of osteosarcoma, providing novel targets for intervention in the treatment of osteosarcoma., (© 2018 The Author(s). Published by S. Karger AG, Basel.)

Objective: Prostate cancer is a kind of malignancy with high occurrence in the male urogenital system. However, the mechanism of the occurrence, the progression, and the metastasis of prostate cancer are still unclear. Searching for the effective molecule target is of great significance to improve the curative effect on prostate cancer. Zinc finger E box binding protein-1 (ZEB1) protein is a member of the zinc finger transcription factor family that participates in the embryonic development and formation. ZEB1 was found to be involved in the occurrence and in the development of multiple cancers, while its role in prostate cancer still needs elucidation., Materials and Methods: Normal prostate cell line PC-3M and prostate cancer cell line DU145 were cultured in vitro and transfected by ZEB1 siRNA. ZEB1 mRNA and protein expressions were detected by real-time PCR and Western blot assay. Cell proliferation was determined by using 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2-H-tetrazolium bromide (MTT) assay. Cell migration was evaluated by transwell assay. Cell apoptosis was evaluated by caspase-3 activity. The impact of ZEB1 on extracellular signal-regulated kinase 1 and 2 (ERK1/2) signaling pathway was assessed by Western blot assay., Results: ZEB1 expression significantly increased in DU145 cells compared with PC-3M cells (p<0.05). ZEB1 mRNA and protein obviously declined, cell proliferation inhibited, cell invasion suppressed, and Caspase-3 activity enhanced in DU145 cells after ZEB1 siRNA transfection (p<0.05). ZEB1 siRNA markedly decreased ERK1/2 phosphorylation in DU145 cells compared with control (p<0.05)., Conclusions: Inhibition of ZEB1 promoted prostate cancer apoptosis, restrained proliferation, and suppressed invasion through down-regulating ERK1/2 signaling pathway.

The zinc finger E-box-binding transcription factor Zeb1 plays a pivotal role in the epithelial-mesenchymal transition. Numerous studies have focused on the molecular mechanisms by which Zeb1 contributes to this process. However, the functions of Zeb1 beyond the epithelial-mesenchymal transition remain largely elusive. Using a transdifferentiation system to convert mouse embryonic fibroblasts (MEFs) into functional neurons via the neuronal transcription factors achaete-scute family bHLH (basic helix-loop-helix) transcription factor1 ( Ascl1 ), POU class 3 homeobox 2 (POU3F2/ Brn2 ), and neurogenin 2 (Neurog2, Ngn2 ) (ABN), we found that Zeb1 was up-regulated during the early stages of transdifferentiation. Knocking down Zeb1 dramatically attenuated the transdifferentiation efficiency, whereas Zeb1 overexpression obviously increased the efficiency of transdifferentiation from MEFs to neurons. Interestingly, Zeb1 improved the transdifferentiation efficiency induced by even a single transcription factor ( e.g. Asc1 or Ngn2 ). Zeb1 also rapidly promoted the maturation of induced neuron cells to functional neurons and improved the formation of neuronal patterns and electrophysiological characteristics. Induced neuron cells could form functional synapse in vivo after transplantation. Genome-wide RNA arrays showed that Zeb1 overexpression up-regulated the expression of neuron-specific genes and down-regulated the expression of epithelial-specific genes during conversion. Taken together, our results reveal a new role for Zeb1 in the transdifferentiation of MEFs into neurons., (© 2017 by The American Society for Biochemistry and Molecular Biology, Inc.)

Objective To down-regulate the expression of zinc-finger E-box binding homeobox 1 (ZEB1) gene by shRNA, and investigate its effect on invasion, migration and proliferation, as well as the related gene expressions of lncRNA HOTAIR and E-cadherin in human gastric cancer BGC823 cells. Methods RNA interfering (RNAi) was used to knock down ZEB1 in gastric cancer BGC823 cells. The recombinant plasmid shZEB1 was constructed and transfected into the gastric cancer BGC823 cells by Lipofectamine TM 2000, and the stably transfected cells were isolated by G418 selection and limited dilution. The expression of ZEB1 mRNA and protein was detected by real-time quantitative PCR and Western blot analysis. Cell proliferation was determined by MTT assay, and the invasion and migration abilities of BGC823 cells were monitored by Transwell TM invasion assay and wound healing assay, respectively. The expressions of lncRNA HOTAIR and E-cadherin mRNA were detected by real-time quantitative PCR. Results After ZEB1 expression was successfully down-regulated in BGC823 cells by siRNA, the proliferation, invasion and migration rates in shZEB1 transfection group were significantly lower than those in control group; meanwhile, the expression of lncRNA HOTAIR was reduced and E-cadherin expression was enhanced. Conclusion Knock-down of ZEB1 expression by RNA interference can decease lncRNA HOTAIR expression and restrain cell proliferation, invasion and migration in gastric cancer BGC823 cells.

Background: A chromosomal locus at 4q32.1 has been genome-wide significantly associated with coronary artery disease risk. The locus encompasses GUCY1A3 , which encodes the α 1 subunit of the soluble guanylyl cyclase (sGC), a key enzyme in the nitric oxide/cGMP signaling pathway. The mechanism linking common variants in this region with coronary risk is not known., Methods: Gene expression and protein expression were analyzed with quantitative polymerase chain reaction and immunoblotting, respectively. Putative allele-specific transcription factors were identified with in silico analyses and validated via allele-specific quantification of antibody-precipitated chromatin fractions. Regulatory properties of the lead risk variant region were analyzed with reporter gene assays. To assess the effect of zinc finger E box-binding homeobox 1 transcription factor (ZEB1), siRNA-mediated knockdown and overexpression experiments were performed. Association of GUCY1A3 genotype and cellular phenotypes was analyzed with vascular smooth muscle cell migration assays and platelet aggregation analyses., Results: Whole-blood GUCY1A3 mRNA levels were significantly lower in individuals homozygous for the lead (rs7692387) risk variant. Likewise, reporter gene assays demonstrated significantly lower GUCY1A3 promoter activity for constructs carrying this allele. In silico analyses located a DNase I hypersensitivity site to rs7692387 and predicted binding of the transcription factor ZEB1 rather to the nonrisk allele, which was confirmed experimentally. Knockdown of ZEB1 resulted in more profound reduction of nonrisk allele promoter activity and a significant reduction of endogenous GUCY1A3 expression. Ex vivo-studied platelets from homozygous nonrisk allele carriers displayed enhanced inhibition of ADP-induced platelet aggregation by the nitric oxide donor sodium nitroprusside and the phosphodiesterase 5 inhibitor sildenafil compared with homozygous risk allele carriers. Moreover, pharmacological stimulation of sGC led to reduced migration only in vascular smooth muscle cells homozygous for the nonrisk allele. In the Hybrid Mouse Diversity Panel, higher levels of GUCY1A3 expression correlated with less atherosclerosis in the aorta., Conclusions: Rs7692387 is located in an intronic site that modulates GUCY1A3 promoter activity. The transcription factor ZEB1 binds preferentially to the nonrisk allele, leading to an increase in GUCY1A3 expression, higher sGC levels, and higher sGC activity after stimulation. Finally, human and mouse data link augmented sGC expression to lower risk of atherosclerosis., (© 2017 American Heart Association, Inc.)

Background: Increasing evidence has indicated an important role for estrogen receptor beta 1 (ERβ1) in breast cancer. However, the role of ERβ1 in the metastasis of androgen receptor (AR)-positive triple-negative breast cancer (TNBC) and the underlying mechanisms are still unknown., Methods: Stable ERβ1-expressing TNBC cell lines were generated for this study. We detected the abilities of cell migration and invasion by wound-healing and transwell assays and the expression of E-cadherin and N-cadherin by quantitative RT-PCR (qRT-PCR) and western blotting assays in TNBC cell lines. Chromatin immunoprecipitation (ChIP) analysis was performed to assess the effect of AR on ERβ1 promoter. Tumor metastasis was evaluated in vivo using a lung metastasis mouse model. Lastly, immunohistochemical expression of ERβ1 in TNBC tissues was analyzed and correlated with clinicopathological features., Results: ERβ1 suppressed the invasion and migration abilities of AR-positive TNBC cells and induced the downregulation of ZEB1. ZEB1 overexpression abrogated the increase in E-cadherin expression and the decrease in N-cadherin expression modulated by ERβ1. A lung metastasis mouse model showed that the incidence of metastasis was lower in ERβ1-expressing TNBC cells. Further, AR activation increased the anti-metastatic effect of ERβ1 in AR-positive TNBC cells, which accelerated ERβ1 transcription by functioning as a transcription factor that bound to the promoter of ERβ1. No significant change was observed in AR expression induced by ERβ1. Immunohistochemistry (IHC) analysis of TNBC clinical samples showed that ERβ1 and AR were positive in 31.7% and 23.2% of samples, respectively. ERβ1 expression was negatively correlated with ZEB1 expression and lymph node metastasis, and positively correlated with the expression of AR and E-cadherin., Conclusion: Our findings suggested a potential role of ERβ1 in metastasis of AR-positive TNBC and provided novel insights into the mechanism of action of ERβ1 and the possible relationship between ERβ1 and AR.

Malignant gliomas are the most common and aggressive type of brain tumor. The suppressive role of ten-eleven translocation 2 (TET2) has been implicated in certain types of cancer, however, its role in gliomas remains to be elucidated. The present study aimed to determine the expression pattern and biological role of TET2 in glioma, using RT-qPCR and immunohistochemistry, and its results indicated that the expression of TET2 was frequently decreased in gliomas and that repression of the expression of TET2 correlated with the progression of glioma. The ectopic expression of TET2 inhibited the invasive potential of glioma cells, and inhibited glioma cell proliferation in vitro and growth in vivo. Additionally, the expression of Zinc finger E‑box‑binding homeobox 1 (ZEB1) was increased in gliomas and was positively correlated with progression, but inversely correlated with the expression of TET2. ZEB1 was also confirmed to physically bind to the TET2 promoter. ZEB1 knockdown resulted in an increase in the expression of TET2 and elevation of TET2 promoter activity in glioma cells. These findings indicated that the downregulation of TET2 by ZEB1 is a critical oncogenic event in gliomas.

Endothelial dysfunction plays a crucial role in the development of diabetic vasculopathy. Our initial quantitative PCR results showed an increased miR-200c expression in arteries from diabetic mice and patients with diabetes. However, whether miR-200c is involved in diabetic endothelial dysfunction is unknown. Overexpression of miR-200c impaired endothelium-dependent relaxations (EDRs) in nondiabetic mouse aortas, whereas suppression of miR-200c by anti-miR-200c enhanced EDRs in diabetic db/db mice. miR-200c suppressed ZEB1 expression, and ZEB1 overexpression ameliorated endothelial dysfunction induced by miR-200c or associated with diabetes. More importantly, overexpression of anti-miR-200c or ZEB1 in vivo attenuated miR-200c expression and improved EDRs in db/db mice. Mechanistic study with the use of COX-2(-/-) mice revealed that COX-2 mediated miR-200c-induced endothelial dysfunction and that miR-200c upregulated COX-2 expression in endothelial cells through suppression of ZEB1 and increased production of prostaglandin E2, which also reduced EDR. This study demonstrates for the first time to our knowledge that miR-200c is a new mediator of diabetic endothelial dysfunction and inhibition of miR-200c rescues EDRs in diabetic mice. These new findings suggest the potential usefulness of miR-200c as the target for drug intervention against diabetic vascular complications., (© 2016 by the American Diabetes Association. Readers may use this article as long as the work is properly cited, the use is educational and not for profit, and the work is not altered.)

Viral, dietary and genetic factors have been implicated in nasopharyngeal carcinoma (NPC), however, the molecular mechanism underlying its pathogenesis remains to be fully elucidated. MicroRNAs (miRNAs) have been reported to be important in NPC tumorigenesis, with a previous miRNA microarray study showing the downregulation of miRNA (miR)‑429 in NPC cells. However, the possible mechanisms of action of miR‑429 have not been examined. In the present study, the expression profiles of miR‑429 were detected using reverse transcription‑quantitative polymerase chain reaction analysis in CNE‑1 and CNE‑2 cells, which are two generally used NPC cells with different degrees of differentiation. Subsequently, cell proliferation, invasion and migration were analyzed in miR‑429‑overexpressing CNE‑2 cells, and the modulatory function of miR‑429 was also investigated using two target genes, zinc finger E‑Box‑binding homeobox 1 (ZEB1) and CRK‑like (CRKL), by transfection with miR‑429 mimic or anti‑miR‑429. Significant changes in the expression of miR‑429 were detected, particularly in low‑differentiated CNE‑2 cells, with higher levels of epidemicity and malignancy. Additional results revealed that miR‑429 inhibited the invasion and migration of the CNE‑2 cells, whereas no significant effect on cell growth was observed. In addition, the mRNA and protein expression levels of the two target genes, ZEB1 and CRKL, were negatively regulated by miR‑429, demonstrated through gain‑of‑function and loss‑of‑function investigations, indicating that these two functional downstream targets may be involved in the inhibitory effects of miR‑429 on NPC migration and invasion. miR‑429 may act as a negative regulatory factor of NPC tumorigenesis, involving the functions of its downstream targets, ZEB1 and CRKL. The results suggested miR‑429 as a potential candidate for miRNA‑based prognosis or therapy against NPC.

Oral submucous fibrosis (OSF) is a precancerous condition of the oral mucosa without specific therapeutic drugs. We previously demonstrated that the zinc finger E-box binding homeobox 1 (ZEB1) plays a pathogenic role in the induction of the myofibroblast activity of buccal mucosal fibroblasts (BMFs) and contributes to the pathogenesis of OSF. Resveratrol is a natural polyphenolic flavonoid with anti-fibrosis activity in various tissues and has the capability to inhibit ZEB1 in oral cancer cells. We examined the effect of resveratrol on the myofibroblast activity of human primary fibrotic BMFs (fBMFs) derived from OSF tissues. With the collagen contraction assay, resveratrol displayed anti-myofibroblast activity in three fBMF lines. Resveratrol also inhibited the expression of fibrogenic genes at the mRNA and protein levels in a dose- and time-dependent manner. The downregulation of ZEB1 in fBMFs by resveratrol was mediated by epigenetic mechanisms, such as the upregulated expression of miR-200c and the enhancer of zeste homolog 2 (EZH2), as well as the trimethylated lysine 27 of histone H3 (H3K27me3). Resveratrol also increased the binding of H3K27me3 to the ZEB1 promoter. The knockdown of EZH2 in fBMFs caused the upregulation of ZEB1 and suppressed the inhibitory effect of resveratrol. Furthermore, the reversed expression pattern between EZH2 and ZEB1 was observed in 6/8 OSF tissues with twofold upregulation of ZEB1 expression compared with the adjacent normal mucosa. In conclusion, our data suggest that resveratrol epigenetically inhibits ZEB1 expression to suppress the myofibroblast activity of fBMFs and may serve as a dietary supplement for OSF patients.