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Zinc finger E‐box binding homeobox 1 (ZEB1) has been identified as a key factor in cancer cell differentiation and metastasis, and has been well studied in the field of cancer cell biology. ZEB2 has a highly similar conformation to ZEB1, but its role in head and neck squamous cell carcinoma (HNSCC) cells is not fully understood. Here, we separately overexpressed ZEB1 and ZEB2 in C57BL/6 mouse oral cancer (MOC) cells and investigated their cellular characteristics, including E‐cadherin levels, motile properties, chemoresistance, and metastatic ability in immunocompetent mice. Both ZEB1 and ZEB2 overexpression reduced epithelial traits and converted cells to an aggressive phenotype. Surprisingly, ZEB1 overexpression increased the endogenous level of ZEB2 in MOC cells, and vice versa. The molecular mechanisms underlying these findings remain unclear. However, the in vitro anchorage‐independent growth of MOC cells overexpressing ZEB2 was considerably greater than that of MOC cells overexpressing ZEB1. These findings suggest that ZEB2, like ZEB1, has the ability to induce the differentiation of cancer cells into those with highly aggressive traits. [ABSTRACT FROM AUTHOR]

Background: Periodontitis can eventually contribute to tooth loss. Zinc finger E‐box binding homeobox 1 (ZEB1) is identified as overexpressed in the gingival tissue of mice with periodontitis. This study is designed to decipher the mechanism of ZEB1's involvement in periodontitis. Methods: Human periodontal mesenchymal stem cells (hPDLSCs) were exposed to LPS to mimic the inflammation in periodontitis. Following ZEB1 silencing, FX1 (an inhibitor of Bcl‐6) treatment or ROCK1 overexpression, cell viability, and apoptosis were analyzed. Alkaline phosphatase (ALP) staining, Alizarin red staining, RT‐qPCR, and western blot were performed to evaluate osteogenic differentiation and mineralization. hPDLSCs were processed for luciferase reporter assay and ChIP‐PCR to confirm the association between ZEB1 and ROCK1. Results: The induction of ZEB1 silencing resulted in reduced cell apoptosis, enhanced osteogenic differentiation, and mineralization. Nevertheless, these effects were significantly blunted by FX1. ZEB1 was confirmed to bind to the promoter sites of ROCK1 and regulate the ROCK1/AMPK. Whereas ROCK1 overexpression reversed the effects of ZEB1 silencing on Bcl‐6/STAT1, as well as cell proliferation and osteogenesis differentiation. Conclusion: hPDLSCs displayed decreased proliferation and weakened osteogenesis differentiation in response to LPS. These impacts were mediated by ZEB1 regulating Bcl‐6/STAT1 via AMPK/ROCK1. [ABSTRACT FROM AUTHOR]

Background: Several biological processes are regulated by miR‐200a‐3p, including cell proliferation, migration, and epithelial–mesenchymal transition (EMT). In this study we aimed to uncover the diagnostic value and molecular mechanisms of miR‐200a‐3p in chronic rhinosinusitis with nasal polyps (CRSwNP). Methods: The expressions of miR‐200a‐3p were detected by quantitative real‐time polymerase chain reaction (qRT‐PCR), Zinc finger E‐box binding homeobox 1 (ZEB1) levels were examined by qRT‐PCR and immunofluorescence staining. The interaction between miR‐200a‐3p and ZEB1 was predicted by TargetScan Human 8.0 and confirmed by dual‐luciferase reporter assays. In addition, the effect of miR‐200a‐3p and ZEB1 on EMT‐related makers and inflammation cytokines was assessed by qRT‐PCR and Western blotting in human nasal epithelial cells (hNEpCs) and primary human nasal mucosal epithelial cells (hNECs). Results: We found that miR‐200a‐3p was downregulated in non‐eosinophilic and eosinophilic CRSwNP patients when compared with controls. The diagnostic value of miR‐200a‐3p in serum is reflected by the receiver operating characteristic curve and the 22‐item Sino‐Nasal Outcome Test. Bioinformatic analysis and luciferase reporter assay identified ZEB1 as a target of miR‐200a‐3p. ZEB1 was more highly expressed in CRSwNP than in controls. Furthermore, miR‐200a‐3p inhibitor or ZEB1 overexpression significantly suppressed the epithelial marker E‐cadherin; promoted the activation of vimentin, α‐spinal muscle atrophy, and N‐cadherin; and aggravated inflammation in hNEpCs. Knockdown of ZEB1 significantly alleviated the cellular remodeling caused by miR‐200a‐3p inhibitor via the extracellular signal‐regulated kinase (ERK)/p38 pathway in hNECs. Conclusions: miR‐200a‐3p suppresses EMT and inflammation by regulating the expression of ZEB1 via the ERK/p38 pathway. Our study presents new ideas for protecting nasal epithelial cells from tissue remodeling and finding a possible target for disease. [ABSTRACT FROM AUTHOR]

Mutations in the splicing factor 3b subunit 1 (SF3B1) gene are frequent in myelodysplastic neoplasms (MDS). Because the splicing process is involved in the production of circular RNAs (circRNAs), we investigated the impact of SF3B1 mutations on circRNA processing. Using RNA sequencing, we measured circRNA expression in CD34+ bone marrow MDS cells. We defined circRNAs deregulated in a heterogeneous group of MDS patients and described increased circRNA formation in higher‐risk MDS. We showed that the presence of SF3B1 mutations did not affect the global production of circRNAs; however, deregulation of specific circRNAs was observed. Particularly, we demonstrated that strong upregulation of circRNAs processed from the zinc finger E‐box binding homeobox 1 (ZEB1) transcription factor; this upregulation was exclusive to SF3B1‐mutated patients and was not observed in those with mutations in other splicing factors or other recurrently mutated genes, or with other clinical variables. Furthermore, we focused on the most upregulated ZEB1‐circRNA, hsa_circ_0000228, and, by its knockdown, we demonstrated that its expression is related to mitochondrial activity. Using microRNA analyses, we proposed miR‐1248 as a direct target of hsa_circ_0000228. To conclude, we demonstrated that mutated SF3B1 leads to deregulation of ZEB1‐circRNAs, potentially contributing to the defects in mitochondrial metabolism observed in SF3B1‐mutated MDS. [ABSTRACT FROM AUTHOR]

Hepatocellular carcinoma (HCC) is an aggressive and fatal disease caused by a subset of cancer stem cells (CSCs). It is estimated that there are approximately 100 000 long noncoding RNAs (lncRNAs) in humans. However, the mechanisms by which lncRNAs affect tumor stemness remain poorly understood. In the present study, it is found that DIO3OS is a conserved lncRNA that is generally downregulated in multiple cancers, including HCC, and its low expression correlates with poor clinical outcomes in HCC. In in vitro cancer cell lines and an in vivo spontaneous HCC mouse model, DIO3OS markedly represses tumor development via its suppressive role in CSCs through downregulation of zinc finger E‐box binding homeobox 1 (ZEB1). Interestingly, DIO3OS represses ZEB1 post‐transcriptionally without affecting its mRNA levels. Subsequent experiments show that DIO3OS interacts with the NONO protein and restricts NONO‐mediated nuclear export of ZEB1 mRNA. Overall, these findings demonstrate that the DIO3OS‐NONO‐ZEB1 axis restricts HCC development and offers a valuable candidate for CSC‐targeted therapeutics for HCC. [ABSTRACT FROM AUTHOR]

Epithelial‐mesenchymal transition (EMT) is a reversible transcriptional program invoked by cancer cells to drive cancer progression. Transcription factor ZEB1 is a master regulator of EMT, driving disease recurrence in poor‐outcome triple negative breast cancers (TNBCs). Here, this work silences ZEB1 in TNBC models by CRISPR/dCas9‐mediated epigenetic editing, resulting in highly‐specific and nearly complete suppression of ZEB1 in vivo, accompanied by long‐lasting tumor inhibition. Integrated "omic" changes promoted by dCas9 linked to the KRAB domain (dCas9‐KRAB) enabled the discovery of a ZEB1‐dependent‐signature of 26 genes differentially‐expressed and ‐methylated, including the reactivation and enhanced chromatin accessibility in cell adhesion loci, outlining epigenetic reprogramming toward a more epithelial state. In the ZEB1 locus transcriptional silencing is associated with induction of locally‐spread heterochromatin, significant changes in DNA methylation at specific CpGs, gain of H3K9me3, and a near complete erasure of H3K4me3 in the ZEB1 promoter. Epigenetic shifts induced by ZEB1‐silencing are enriched in a subset of human breast tumors, illuminating a clinically‐relevant hybrid‐like state. Thus, the synthetic epi‐silencing of ZEB1 induces stable "lock‐in" epigenetic reprogramming of mesenchymal tumors associated with a distinct and stable epigenetic landscape. This work outlines epigenome‐engineering approaches for reversing EMT and customizable precision molecular oncology approaches for targeting poor outcome breast cancers. [ABSTRACT FROM AUTHOR]

Understanding the molecular mechanisms underlying osteoclast differentiation provides insights into bone loss and even osteoporosis. The specific mechanistic actions of cullin 4A (CUL4A) in osteoclast differentiation and resultant osteoporosis is poorly explored. We developed a mouse model of osteoporosis using bilateral ovariectomy (OVX) and examined CUL4A expression. It was noted that CUL4A expression was increased in the bone marrow of OVX mice. Overexpression of CUL4A promoted osteoclast differentiation, and knockdown of CUL4A alleviated osteoporosis symptoms of OVX mice. Bioinformatic analyses were applied to identify the downstream target genes of microRNA‐340‐5p (miR‐340‐5p), followed by interaction analysis. The bone marrow macrophages (BMMs) were isolated from femur of OVX mice, which were transfected with different plasmids to alter the expression of CUL4A, Zinc finer E‐box binding homeobox 1 (ZEB1), miR‐340‐5p, and Toll‐like receptor 4 (TLR4). ChIP assay was performed to detect enrichment of ZEB1 promoter by H3K4me3 antibody in BMMs. ZEB1 was overexpressed in the bone marrow of OVX mice. Overexpression of CUL4A mediated H3K4me3 methylation to increase ZEB1 expression, thus promoting osteoclast differentiation. Meanwhile, ZEB1 could inhibit miR‐340‐5p expression and upregulate HMGB1 to induce osteoclast differentiation. Overexpressed ZEB1 activated the TLR4 pathway by regulating the miR‐340‐5p/HMGB1 axis to induce osteoclast differentiation, thus promoting the development of osteoporosis. Overall, E3 ubiquitin ligase CUL4A can upregulate ZEB1 to repress miR‐340‐5p expression, leading to HMGB1 upregulation and the TLR4 pathway activation, which promotes osteoclast differentiation and the development of osteoporosis. [ABSTRACT FROM AUTHOR]

Chemoresistance is associated with tumor recurrence, metastases, and short survival. Cisplatin is one of the most used chemotherapies in cancer treatment, including head and neck squamous cell carcinoma (HNSCC), and many patients develop resistance. Here, we established cell lines resistant to cisplatin to better understand epigenetics and biological differences driving the progression of HNSCC after treatment. Cisplatin resistance was established in CAL‐27 and SCC‐9 cell lines. Gene expression of HDAC1, HDAC2, SIRT1, MTA1, KAT2B, KAT6A, KAT6B, and BRD4 indicated the cisplatin activates the epigenetic machinery. Increases in tumor aggressiveness were detected by BMI‐1 and KI‐67 in more resistant cell lines. Changes in cellular shape and epithelial–mesenchymal transition (EMT) activation were also observed. HDAC1 and ZEB1 presented an opposite distribution with down‐regulation of HDAC1 and up‐regulation of ZEB1 in the course of chemoresistance. Up‐regulation of ZEB1 and BMI‐1 in patients with HNSCC is also associated with a poor response to therapy. Cancer stem cells (CSC) population increased significantly with chemoresistance. Down‐regulation of HDAC1, HDAC2, and SIRT1 and accumulation of Vimentin and ZEB1 were observed in the CSC population. Our results suggest that in the route to cisplatin chemoresistance, epigenetic modifications can be associated with EMT activation and CSC accumulation which originate more aggressive tumors. [ABSTRACT FROM AUTHOR]

Distal metastases from breast cancer, especially bone metastases, are extremely common in the late stages of the disease and are associated with a poor prognosis. EMT is a biomarker of the early process of bone metastasis, and MMP‐9 and MMP‐13 are important osteoclastic activators. Previously, we found that meso‐Hannokinol (HA) could significantly inhibit EMT and MMP‐9 and MMP‐13 expressions in breast cancer cells. On this basis, we further explored the role of HA in breast cancer bone metastasis. In vivo, we established a breast cancer bone metastasis model by intracardially injecting breast cancer cells. Intraperitoneal injections of HA significantly reduced breast cancer cell metastasis to the leg bone in mice and osteolytic lesions caused by breast cancer. In vitro, HA inhibited the migration and invasion of breast cancer cells and suppressed the expressions of EMT, MMP‐9, MMP‐13, and other osteoclastic activators. HA inhibited EMT and MMP‐9 by activating the ROS/JNK pathway as demonstrated by siJNK and SP600125 inhibition of JNK phosphorylation and NAC scavenging of ROS accumulation. Moreover, HA promoted bone formation and inhibited bone resorption in vitro. In conclusion, our findings suggest that HA may be an excellent candidate for treating breast cancer bone metastasis. [ABSTRACT FROM AUTHOR]

Background: Globally, nasopharyngeal carcinoma (NPC) is a prevalent and deadly malignancy. Despite the role of methyltransferase like 13 (METTL13) having been highlighted in a majority of human cancers, its function and mechanism in NPC is indistinct. Methods: The expression level of METTL13 in NPC cell lines and normal cells was detected using a quantitative real‐time polymerase chain reaction. Gain‐ and loss‐of function experiments were conducted. Cell counting kit‐8, 5‐ethynyl‐2′‐deoxyuridine, wound‐healing, Transwell and tube formation assays, respectively, appraised the proliferative, migratory, invasive and angiogenic cellular responses. Corresponding protein expression was measured by western blotting. A chromatin immunoprecipitation assay was applied to verify the association between ZEB1 and the TPT1 promoter. Eventually, to substantiate the critical role of METTL13 in NPC, the establishment of an in vivo tumorigenesis model was accomplished. Results: METTL13 possessed fortified expression in NPC cells. METTL13 silencing markedly suppressed NPC cellular phenotypes in vitro, including proliferative, migratory, invasive and angiogenic events, as well as hindered tumorigenesis in vivo. Additionally, METTL13 positively regulated ZEB1, whereas ZEB1 could bind to TPT1 promoter and transcriptionally regulate TPT1. TPT1 was also found to be upregulated in NPC cells. TPT1 silencing suppressed NPC cellular phenotypes in vitro. TPT1 overexpression partly weakened the anti‐tumor effect of METTL13 in NPC. Conclusions: In summary, METTL13 up‐regulated ZEB1, which facilitated the transcriptional activation of TPT1, ultimately promoting NPC growth and metastasis, providing a potential therapeutic strategy for NPC treatment. [ABSTRACT FROM AUTHOR]

Osteoclasts are bone‐resorbing polykaryons responsible for skeletal remodeling during health and disease. Coincident with their differentiation from myeloid precursors, osteoclasts undergo extensive transcriptional and metabolic reprogramming in order to acquire the cellular machinery necessary to demineralize bone and digest its interwoven extracellular matrix. While attempting to identify new regulatory molecules critical to bone resorption, we discovered that murine and human osteoclast differentiation is accompanied by the expression of Zeb1, a zinc‐finger transcriptional repressor whose role in normal development is most frequently linked to the control of epithelial‐mesenchymal programs. However, following targeting, we find that Zeb1 serves as an unexpected regulator of osteoclast energy metabolism. In vivo, Zeb1‐null osteoclasts assume a hyperactivated state, markedly decreasing bone density due to excessive resorptive activity. Mechanistically, Zeb1 acts in a rheostat‐like fashion to modulate murine and human osteoclast activity by transcriptionally repressing an ATP‐buffering enzyme, mitochondrial creatine kinase 1 (MtCK1), thereby controlling the phosphocreatine energy shuttle and mitochondrial respiration. Together, these studies identify a novel Zeb1/MtCK1 axis that exerts metabolic control over bone resorption in vitro and in vivo. Synopsis: Osteoporosis and similar bone‐wasting conditions can be caused by an increase in osteoclast‐mediated bone resorption. Here, we learn that both murine and human osteoclasts are activated by a Zeb1‐dependent regulation of mitochondrial energy metabolism.The transcription factor Zeb1 is a negative regulator of giant multinucleated osteoclast‐mediated skeletal remodeling.Zeb1 regulates mitochondrial energy metabolism in myeloid lineage‐derived osteoclasts.The mitochondrial creatine kinase MtCK1 is a transcriptional target of Zeb1 that enables bone resorption by buffering ATP availability. [ABSTRACT FROM AUTHOR]

Purpose Posterior corneal vesicles (PCVs) have clinical features that are similar to posterior polymorphous corneal dystrophy (PPCD). To help determine whether there is a shared genetic basis, we screened 38 individuals with PCVs for changes in the three genes identified as causative for PPCD. Methods: We prospectively recruited patients for this study. We examined all individuals clinically, with their first‐degree relatives when available. We used a combination of Sanger and exome sequencing to screen regulatory regions of OVOL2 and GRHL2, and the entire ZEB1 coding sequence. Results: The median age at examination was 37.5 years (range 4.7–84.0 years), 20 (53%) were male and in 19 (50%) the PCVs were unilateral. Most individuals were discharged to optometric review, but five had follow‐up for a median of 12 years (range 5–13 years) with no evidence of progression. In cases with unilateral PCVs, there was statistically significant evidence that the change in the affected eye was associated with a lower endothelial cell density (p = 0.0003), greater central corneal thickness (p = 0.0277) and a steeper mean keratometry (p = 0.0034), but not with a higher keratometric astigmatism or a reduced LogMAR visual acuity. First‐degree relatives of 13 individuals were available for examination, and in 3 (23%), PCVs were identified. No possibly pathogenic variants were identified in the PPCD‐associated genes screened. Conclusion: We found no evidence that PCVs share the same genetic background as PPCD. In contrast to PPCD, we confirm that PCVs is a mild, non‐progressive condition with no requirement for long‐term review. However, subsequent cataract surgery can lead to corneal oedema. [ABSTRACT FROM AUTHOR]

Angiogenesis has been identified to assume a critical role in skin wound healing. Moreover, zinc finger E‐box binding homeobox 1 (ZEB1) was capable of promoting skin wound healing. Herein, cell and animal experiments were implemented in this study to figure out whether ZEB1 orchestrated angiogenesis during skin wound healing. Subsequent to gain‐ and loss‐of‐function approaches in human dermal microvascular endothelial cells (HDMECs), HDMEC proliferation, migration and angiogenesis were evaluated by CCK8, EdU, wound healing, Transwell and angiogenesis in vitro assays. The relationship among ZEB1, microRNA (miR)‐206 and vascular endothelial growth factor A (VEGFA) was assessed by microarray analysis, dual‐luciferase, ChIP and RIP assays. Finally, the mechanism of ZEB1 in skin wound healing was confirmed by in vivo experiments. Mechanically, ZEB1 upregulation resulted in miR‐206 downregulation by binding to miR‐206 promoter, and miR‐206 repressed VEGFA expression by directly targeting. ZEB1 overexpression enhanced HDMEC proliferation, migration and angiogenesis, which was neutralized by miR‐206 upregulation or VEGFA inhibition. Moreover, ZEB1 significantly promoted skin wound healing in mice, which was negated by overexpression of miR‐206. Conclusively, ZEB1 augmented angiogenesis to promote skin wound healing by elevating VEGFA expression via miR‐206 repression. [ABSTRACT FROM AUTHOR]

Homologous to the E6‐associated protein carboxyl terminus domain containing 3 (HECTD3) has been reported to play a role in carcinogenesis. Here, we explored the role of HECTD3 in regulating the radiation resistance of glioma, and the underlying mechanism. HECTD3 expressions in glioma tissues were assessed using Western blotting, quantitative reverse transcription (qRT)‐polymerase chain reaction (PCR) and immunohistochemistry. Glioma cells were exposed to 2‐, 4‐, 6‐ or 8‐Gy X‐ray to mimic the radiation treatment. Cell count kit‐8 (CCK‐8), clone formation assay, flow cytometry assay, transwell chambers and animal assay were used to test cell viability, apoptosis, migration, invasiveness and tumourigenesis, respectively. HECTD3 expression was increased in glioma tissues, especially from patients with radiation resistance. Knockdown of HECTD3 promoted cell apoptosis and inhibited cell viability under the condition of 8‐Gy X‐ray, as well as suppressed cell migration and invasiveness. In mechanism, HECTD3 positively regulated ZEB1 (zinc finger E‐box binding hemeobox 1) expression through regulating the ubiquitination of liver kinase B1 (LKB1) protein. Overexpression of ZEB1 significantly abolished the effects of HECTD3 downregulation in inhibiting the radiation resistance and migration of glioma cells. Moreover, downregulation of HECTD3 further enhanced the anti‐tumour effect of X‐ray on glioma growth in vivo. In conclusion, HECTD3 was overexpressed in glioma patients with radiation resistance. Knockdown of HECTD3 sensitized glioma cells to radiation and inhibited cell migration by downregulating ZEB1 expression via regulating the ubiquitination of LKB1 protein. This study reveals that HECTD3 might be a potent target to enhance the radiation sensitivity of glioma. [ABSTRACT FROM AUTHOR]

Aims: The pathological diagnosis of undifferentiated and de‐differentiated endometrial carcinomas (UC/DCs) is prognostically important. However, undifferentiated components may be confused with other subtypes, particularly grade 3 endometrioid carcinomas (G3ECs). Zinc finger E‐box binding homeobox 1 (ZEB1) has recently been identified as a promising marker because it is frequently expressed in the undifferentiated components of UC/DCs, but not in other carcinomas. Therefore, we herein evaluated the diagnostic utility of ZEB1 with an emphasis on distinguishing between UC/DCs and G3ECs using an expanded cohort of endometrial carcinomas and carcinosarcomas. Methods and results: Immunostaining for ZEB1 was performed on whole‐tissue sections of 19 UC/DCs, 194 non‐UC/DC endometrial carcinomas and 29 carcinosarcomas. Staining was defined as negative (< 5%), focal (5–50%) and diffuse expression (> 50%). ZEB1 was expressed in 84% of the undifferentiated components of UC/DCs (diffuse in 14, focal in two). Focal expression was observed in eight non‐UC/DC endometrial carcinomas and diffuse expression in seven, with the latter comprising G3ECs (four of 76), serous carcinoma (one of 37), clear cell carcinoma (one of 21) and neuroendocrine carcinoma (one of three). Epithelial differentiation was morphologically and immunohistochemically less evident in G3ECs and neuroendocrine carcinoma with diffuse ZEB1 expression. All carcinosarcomas showed diffuse ZEB1 expression in their sarcomatous components. Conclusion: Immunostaining for ZEB1 was sufficiently sensitive to detect undifferentiated components. Diffuse ZEB1 expression showed high specificity for distinguishing between undifferentiated components and G3ECs; however, ZEB1 expression was not entirely specific to UC/DCs. The integration of ZEB1 into the diagnosis of UC/DCs requires careful examination to exclude other tumours, such as less differentiated G3ECs, neuroendocrine carcinomas and carcinosarcomas. [ABSTRACT FROM AUTHOR]

The epithelial-mesenchymal transition (EMT) is a crucial morphological event that occurs during epithelial tumor progression. Snail and ZEB1/2 (ZEB1 and ZEB2), known as EMT transcription factors, are key regulators of this transition. ZEB1/2 are positively correlated with EMT phenotypes and the aggressiveness of cancers. On the contrary, Snail is also correlated with the aggressiveness of cancers, but is not correlated with the expression of EMT marker proteins. Snail is induced by transforming growth factor-b (TGF-b), a well-known inducer of EMT, in various cancer cells. Interestingly, Snail induction by TGF-b is markedly enhanced by active Ras signals. Thus, cancer cells harboring an active Ras mutation exhibit a drastic induction of Snail by TGF-b alone. Here, we found that members of the E26 transformation-specific (Ets) transcription factor family, Ets1 and Ets2, contribute to the upregulation of both Snail and ZEB1/2. Snail induction by TGF-b and active Ras is dramatically inhibited using siRNAs against both Ets1 and Ets2 together, but not on their own; in addition, siRNAs against both Ets1 and Ets2 also downregulate the constitutive expression of Snail and ZEB1/2 in cancer cells. Examination of several alternatively spliced variants of Ets1 revealed that p54-Ets1, which includes exon VII, but not p42-Ets1, which excludes exon VII, regulates the expression of the EMT transcription factors, suggesting that Ets1 is a crucial molecule for regulating Snail and ZEB1/2, and thus cancer progression is mediated through post-translational modification of the exon VII domain. [ABSTRACT FROM AUTHOR]

Numerous epithelial–mesenchymal transition (EMT) characteristics have now been demonstrated to participate in tumor development. Indeed, EMT is involved in invasion, acquisition of stem cell properties, and therapy‐associated resistance of cancer cells. Together, these mechanisms offer advantages in adapting to changes in the tumor microenvironment. However, recent findings have shown that EMT‐associated transcription factors (EMT‐TFs) may also be involved in DNA repair. A better understanding of the coordination between the DNA repair pathways and the role played by some EMT‐TFs in the DNA damage response (DDR) should pave the way for new treatments targeting tumor‐specific molecular vulnerabilities, which result in selective destruction of cancer cells. Here we review recent advances, providing novel insights into the role of EMT in the DDR and repair pathways, with a particular focus on the influence of EMT on cellular sensitivity to damage, as well as the implications of these relationships for improving the efficacy of cancer treatments. [ABSTRACT FROM AUTHOR]

New Findings: What is the central question of this study?The aim was to investigate the function of brahma‐related gene‐1 (BRG1) in airway remodelling epithelial‐to‐mesenchymal transition (EMT) of asthma and identify the transcription factor of BRG1 that binds to the protomer of E‐cadherin.What is the main finding and its importance?This study highlighted an important molecular mechanism involving chromatin remodelling factor BRG1 that played a crucial role in airway remodelling EMT of asthma and demonstrated that ZEB1 was the key transcription factor recruiting BRG1. This finding might offer new insights into gene‐based therapy for asthma. Epithelial‐to‐mesenchymal transition (EMT) of airway remodelling happens in children with asthma. A reduction in the epithelial marker E‐cadherin is reported to be one of the initiating factors of EMT. Our previous study showed that chromatin remodelling factor brahma‐related gene‐1 (BRG1) could regulate the expression of E‐cadherin indirectly. However, the transcription factor involved in the recruitment of BRG1 in asthma is unknown. Here, we studied the function of Brg1 in an ovalbumin‐induced asthma model [lung‐specific conditional Brg1 knockdown (Brg1−/−) mice] and human bronchial epithelial 16HBE cells stably expressing BRG1 short hairpin RNA. Our results showed that Brg1 was involved in EMT in asthmatic mice by detecting the expression of EMT markers. We also identified that BRG1 participated in the transforming growth factor‐β‐induced EMT of 16HBE cells. We observed that zinc finger E‐box binding homeobox 1 (ZEB1) and BRG1 co‐localized in the EMT of TGF‐β‐induced 16HBE cells. Further results revealed that ZEB1 recruited BRG1 and bound to the promoter region (+3563/3715) to regulate E‐cadherin expression. Thus, ZEB1 might be the key transcription factor to recruit BRG1 in airway remodelling EMT of asthma and might be a new therapeutic target. [ABSTRACT FROM AUTHOR]

Colorectal cancer (CRC) with a mesenchymal gene expression signature has the greatest propensity for distant metastasis and is characterised by the accumulation of cancer‐associated fibroblasts in the stroma. We investigated whether the epithelial to mesenchymal transition status of CRC cells influences fibroblast phenotype, with a focus on the transfer of extracellular vesicles (EVs), as a controlled means of cell–cell communication. Epithelial CRC EVs suppressed TGF‐β‐driven myofibroblast differentiation, whereas mesenchymal CRC EVs did not. This was driven by miR‐200 (miR‐200a/b/c, ‐141), which was enriched in epithelial CRC EVs and transferred to recipient fibroblasts. Ectopic miR‐200 expression or ZEB1 knockdown, in fibroblasts, similarly suppressed myofibroblast differentiation. Supporting these findings, there was a strong negative correlation between miR‐200 and myofibroblastic markers in a cohort of CRC patients in the TCGA dataset. This was replicated in mice, by co‐injecting epithelial or mesenchymal CRC cells with fibroblasts and analysing stromal markers of myofibroblastic phenotype. Fibroblasts from epithelial tumours contained more miR‐200 and expressed less ACTA2 and FN1 than those from mesenchymal tumours. As such, these data provide a new mechanism for the development of fibroblast heterogeneity in CRC, through EV‐mediated transfer of miRNAs, and provide an explanation as to why CRC tumours with greater metastatic potential are CAF rich. [ABSTRACT FROM AUTHOR]

Cardiac mesenchymal cells (CMCs) are a promising cell type that showed therapeutic potential in heart failure models. The analysis of the underlying mechanisms by which the CMCs improve cardiac function is on track. This study aimed to investigate the expression of N‐Cadherin, a transmembrane protein that enhances cell adhesion, and recently gained attention for differentiation and augmentation of stem cell function. The mouse CMCs were isolated and analyzed for the mesenchymal markers using flow cytometry. Quantitative real‐time polymerase chain reaction (qRT‐PCR) and western blot analysis were used to assess the expression of N‐Cadherin along with its counteracting molecule E‐Cadherin and their regulator Zeb1 in CMCs and dermal fibroblast. The expression level of miR‐200c and miR‐429 was analyzed using miRNA assays. Transient transfection of miR‐200c followed by qRT‐PCR, western blot analysis, and immunostaining was done in CMCs to analyze the expression of Zeb1, N‐Cadherin, and E‐Cadherin. Flow cytometry analysis showed that CMCs possess mesenchymal markers and absence for hematopoietic and immune cell markers. Increased expression of N‐Cadherin and Zeb1 in CMCs was observed in CMCs at both RNA and protein levels compared to fibroblast. We found significant downregulation of miR‐200c and miR‐429 in CMCs. The ectopic expression of miR‐200c in CMCs significantly downregulated Zeb1 and N‐Cadherin expression. Our findings suggest that the significant downregulation of miR‐200c/429 in CMCs maintains the expression of N‐Cadherin, which may be important for its functional integrity. [ABSTRACT FROM AUTHOR]

The process of epithelial–mesenchymal transition (EMT) is fundamental for embryonic morphogenesis. Cells undergoing it lose epithelial characteristics and integrity, acquire mesenchymal features, and become motile. In cancer, this program is hijacked to confer essential changes in morphology and motility that fuel invasion. In addition, EMT is increasingly understood to orchestrate a large variety of complementary cancer features, such as tumor cell stemness, tumorigenicity, resistance to therapy and adaptation to changes in the microenvironment. In this review, we summarize recent findings related to these various classical and non‐classical functions, and introduce EMT as a true tumorigenic multi‐tool, involved in many aspects of cancer. We suggest that therapeutic targeting of the EMT process will—if acknowledging these complexities—be a possibility to concurrently interfere with tumor progression on many levels. [ABSTRACT FROM AUTHOR]

Colorectal cancer (CRC) is a recurring cancer that is often resistant to conventional therapies and therefore requires the development of molecular‐based therapeutic approaches. Dopamine receptor D2 (DRD2) is associated with the growth of many types of tumors, but its oncogenic role in CRC is unclear. Here, we observed that elevated DRD2 expression was associated with a poor survival rate among patients with CRC. Depletion of DRD2 suppressed CRC cell growth and motility by downregulating β‐catenin/ZEB signaling in vitro and in vivo, whereas overexpression of DRD2 promoted CRC cell progression. Inhibition of DRD2 by the antagonist pimozide inhibited tumor growth and lymph node metastasis in vivo and enhanced the cytotoxic effects of conventional agents in vitro. Taken together, our findings indicate that targeting the DRD2/β‐catenin/ZEB1 signaling axis is a potentially promising therapeutic strategy for patients with CRC. [ABSTRACT FROM AUTHOR]

Background: Ocular adnexal (OA) sebaceous carcinoma is an aggressive malignancy. Oncologic drivers of ocular sebaceous carcinoma are incompletely understood. Methods: A retrospective search of our pathology archives for OA sebaceous carcinoma identified 18 primary resection specimens. Immunohistochemistry for p16 and ZEB1 and RNA in situ hybridization for high‐risk human papillomavirus (HPV) subtypes were performed. Results: High‐risk HPV was demonstrated in 2/11 (18%) cases. p16 overexpression was observed in 10/11 (91%). No association between gender, age at presentation, tumor location, intraepithelial spread, tumor size, and T stage was observed between HPV‐driven and nonviral cases. High expression of ZEB1 was observed in the intraepithelial component of 4/14 (28%) cases and in the subepithelial component of 1/13 (7%) cases. ZEB1 overexpression was not associated with HPV status, T stage, or tumor size. Conclusion: As previously described by others, our findings suggest that a subset of OA sebaceous carcinomas may arise via an HPV‐dependent pathway. However, unlike high‐risk HPV‐driven carcinomas of the oropharynx, we did not identify an association between HPV‐status and prognostic features. Furthermore, p16 expression was not a useful surrogate marker for HPV‐driven disease. ZEB1 overexpression is not associated with HPV in our cohort of ocular sebaceous carcinoma. [ABSTRACT FROM AUTHOR]

Arsenic is a contaminant found in many foods and drinking water. Exposure to arsenic during development can cause improper neuronal progenitor cell development, differentiation, and function, while in vitro studies have determined that acute arsenic exposure to stem and progenitor cells reduced their ability to differentiate. In the current study, P19 mouse embryonal stem cells were exposed continuously to 0.1‐μM (7.5 ppb) arsenic for 32 weeks. A cell lineage array examining messenger RNA (mRNA) changes after 8 and 32 weeks of exposure showed that genes involved in pluripotency were increased, whereas those involved in differentiation were reduced. Therefore, temporal changes of select pluripotency and neuronal differentiation markers throughout the 32‐week chronic arsenic exposure were investigated. Sox2 and Oct4 mRNA expression were increased by 1.9‐ to 2.5‐fold in the arsenic‐exposed cells, beginning at Week 12. Sox2 protein expression was similarly increased starting at Week 16 and remained elevated by 1.5‐fold to sixfold. One target of Sox2 is N‐cadherin, whose expression is a hallmark of epithelial–mesenchymal transitions (EMTs). Exposure to arsenic significantly increased N‐cadherin protein levels beginning at Week 20, concurrent with increased grouping of N‐cadherin positive cells at the perimeter of the embryoid body. Expression of Zeb1, which helps increase the expression of Sox2, was also increased started at Week 16. In contrast, Gdf3 mRNA expression was reduced by 3.4‐ to 7.2‐fold beginning at Week 16, and expression of its target protein, phospho‐Smad2/3, was also reduced. These results suggest that chronic, low‐level arsenic exposure may delay neuronal differentiation and maintain pluripotency. Arsenic is a contaminant found in drinking water, and exposure to arsenic can impair cellular differentiation. P19 mouse embryonal stem cells were exposed to 0.1‐μM (7.5 ppb) arsenic for 32 weeks. The results indicate that transcripts involved in differentiation were reduced starting at Week 16, including Gdf3, a marker of early neuronal differentiation. In contrast, expression of pluripotency markers, including Sox2 and Zeb1, and their target proteins, such as N‐cadherin, was increased. [ABSTRACT FROM AUTHOR]

Zinc finger E‐box binding homeobox 1 (ZEB1), an important transcription factor belonging to the ZEB family, plays a crucial role in regulating gene expression required for both normal physiological and pathological processes. Accumulating evidence has shown that ZEB1 participates in the initiation and progression of atherosclerotic cardiovascular disease. Recent studies suggest that ZEB1 protects against atherosclerosis by regulation of endothelial cell angiogenesis, endothelial dysfunction, monocyte‐endothelial cell interaction, macrophage lipid accumulation, macrophage polarization, monocyte‐vascular smooth muscle cell (VSMC) interaction, VSMC proliferation and migration, and T cell proliferation. In this review, we summarize the recent progress of ZEB1 in the pathogenesis of atherosclerosis and provide insights into the prevention and treatment of atherosclerotic cardiovascular disease. [ABSTRACT FROM AUTHOR]

Osteosarcoma is an often‐fatal mesenchyme‐derived malignancy in children and young adults. Overexpression of EMT‐transcription factors (EMT‐TFs) has been associated with poor clinical outcome. Here, we demonstrated that the EMT‐TF ZEB1 is able to block osteoblastic differentiation in normal bone development as well as in osteosarcoma cells. Consequently, overexpression of ZEB1 in osteosarcoma characterizes poorly differentiated, highly metastatic subgroups and its depletion induces differentiation of osteosarcoma cells. Overexpression of ZEB1 in osteosarcoma is frequently associated with silencing of the imprinted DLK‐DIO3 locus, which encodes for microRNAs targeting ZEB1. Epigenetic reactivation of this locus in osteosarcoma cells reduces ZEB1 expression, induces differentiation, and sensitizes to standard treatment, thus indicating therapeutic options for ZEB1‐driven osteosarcomas. © 2021 The Authors. The Journal of Pathology published by John Wiley & Sons, Ltd. on behalf of The Pathological Society of Great Britain and Ireland. [ABSTRACT FROM AUTHOR]

Acute myeloid leukaemia is a complex, highly aggressive hematopoietic disorder. Currently, in spite of great advances in radiotherapy and chemotherapy, the prognosis for AML patients with initial treatment failure is still poor. Therefore, the need for novel and efficient therapies to improve AML treatment outcome has become desperately urgent. In this study, we identified the expression of ZEB1 (a transcription factor) and focused on its possible role and mechanisms in the progression of AML. According to the data provided by the Gene Expression Profiling Interactive Analysis (GEPIA), high expression of ZEB1 closely correlates with poor prognosis in AML patients. Additionally, the overexpression of ZEB1 was observed in both AML patients and cell lines. Further functional experiments showed that ZEB1 depletion can induce AML differentiation and inhibit AML proliferation in vitro and in vivo. Moreover, ZEB1 expression was negatively correlated with tumour suppressor P53 expression and ZEB1 can directly bind to P53. Our results also revealed that ZEB1 can regulate PTEN/PI3K/AKT signalling pathway. The inhibitory effect of ZEB1 silencing on PTEN/PI3K/AKT signalling pathway could be significantly reversed by P53 small interfering RNA treatment. Overall, the present data indicated that ZEB1 may be a promising therapeutic target for AML treatment or a potential biomarker for diagnosis and prognosis. [ABSTRACT FROM AUTHOR]

Background: Zinc‐finger E‐box‐binding homeobox 1 (ZEB1) is an important regulator of epithelial‐mesenchymal transition (EMT) and is involved in the maintenance of cancer stem cells (CSCs) via miR‐200c and BMI1 pathway. Recent studies revealed that ZEB1 contributes to the EMT‐mediated acquired resistance to gefitinib in EGFR‐mutant non‐small cell lung cancer (NSCLC). However, the precise role of ZEB1 in the maintenance of lung CSCs that lead to acquired resistance to gefitinib remains unclear. Methods: PC9 and HCC827 NSCLC cell lines were treated with high concentrations of gefitinib, and surviving cells were referred to as "gefitinib‐resistant persisters" (GRPs). ZEB1 knockdown or overexpression was performed to determine the biological significance of ZEB1 in the CSC features of GRPs, and animal models were studied for in vivo validation. Expression of ZEB1, BMI1, and ALDH1A1 was analyzed by immunohistochemistry in tumor specimens from NSCLC patients with acquired resistance to gefitinib. Results: GRPs had characteristic features of mesenchymal and CSC phenotypes with high expression of ZEB1 and BMI1, and decreased miR‐200c, in vitro and in vivo. ZEB1 silencing attenuated the suppression of miR‐200c, resulting in the reduction in BMI1 and reversed the mesenchymal and CSC features of GRPs. Furthermore, ZEB1 overexpression induced EMT and increased the levels of CD133‐ and BMI1‐positive GRPs in vitro and gefitinib resistance in vivo. Finally, ZEB1, BMI1, and ALDH1A1 were highly expressed in tumor specimens from EGFR‐mutant NSCLC patients with gefitinib resistance. Conclusions: ZEB1 plays an important role in gefitinib‐resistant lung CSCs with EMT features via regulation of miR‐200c and BMI1. [ABSTRACT FROM AUTHOR]

E‐cadherin, an epithelial cell–specific cell adhesion molecule, has both promoting and suppressing effects on tumor invasion and metastasis. It is often downregulated during cancer progression through gene deletion/mutation, transcriptional repression, or epigenetic silencing. We describe a novel regulatory switch to induce stimulus‐dependent downregulation of mRNA encoding E‐cadherin (CDH1 mRNA) in KRAS‐mutated cancer cells. The regulatory switch consists of ZEB1 and oncogenic K‐Ras, does not target the promoter region of CDH1, and requires an external cue to temporally downregulate E‐cadherin expression. Its repressive effect is maintained as long as the external stimulus continues and is attenuated with cessation of the stimulus. Contextual external cues that turn this regulatory switch on include activation of protein kinase C or fibroblast growth factor signaling. The mode of action is distinct from that of EPCAM repression by ZEB1, which does not require an external cue. Thus, KRAS‐mutated cancer cells acquire a novel mode of regulating E‐cadherin expression depending on ZEB1, which could contribute to phenotypic plasticity of cancer cells during malignant progression. [ABSTRACT FROM AUTHOR]

LncRNA TUG1 has been rarely studied in ovarian cancer (OC), our objective was to explore the role of TUG1 in the regulation of malignant phenotypes of OC. Vectors of sh‐TUG1, miR‐186‐5p and pcDNA‐ZEB1 were, respectively, constructed and used to infect OC cells. MTT and transwell assays were applied for representing cell proliferation and invasion, respectively. Sphere formation experiment was used to detect the stemness of OC cells. Western blotting and qRT‐PCR were employed for detecting the expression of multiple biomarkers on protein and RNA levels, respectively. The luciferase assay was performed to reveal the interactions between miR‐186‐5p and TUG1 or ZEB1. The silencing of TUG1 and upregulation of miR‐186‐5p both suppressed the cell proliferation, invasion and cancer stem cell (CSC) properties. Additionally, luciferase assay verified that miR‐186‐5p directly binds TUG1 and ZEB1. Moreover, overexpression of ZEB1 rescued the impact on the proliferation, invasion and stemness of TUG1 silencing in OC. TUG1 sponges miR‐186‐5p to release ZEB1 and promotes the proliferation, invasion and stemness of OC cells, suggesting that TUG1 could be a potential therapeutic target for OC therapy. Significance of the study: LncRNA TUG1 could promote proliferation, invasion and stemness of ovarian cancer cells. Our study first discovered that TUG1 play a tumourigenic role in ovarian cancer by regulating stemness of cancer cells. Mechanism research exhibited the regulation role of TUG1 in ovarian cancer cells was miR‐186‐5p/ZEB1 axis depended. These results provided a new perspective to understand the pathogenesis and development of ovarian cancer; it will offer new evidence for better diagnosis and treatment therapy of ovarian cancer. [ABSTRACT FROM AUTHOR]

High fructose intake is a risk factor for liver fibrosis. Polydatin is a main constituent of the rhizome of Polygonum cuspidatum, which has been used in traditional Chinese medicine to treat liver fibrosis. However, the underlying mechanisms of fructose‐driven liver fibrosis as well as the actions of polydatin are not fully understood. In this study, fructose was found to promote zinc finger E‐box binding homeobox 1 (ZEB1) nuclear translocation, decrease microRNA‐203 (miR‐203) expression, increase survivin, activate transforming growth factor β1 (TGF‐β1)/Smad signalling, down‐regulate E‐cadherin, and up‐regulate fibroblast specific protein 1 (FSP1), vimentin, N‐cadherin and collagen I (COL1A1) in rat livers and BRL‐3A cells, in parallel with fructose‐induced liver fibrosis. Furthermore, ZEB1 nuclear translocation‐mediated miR‐203 low‐expression was found to target survivin to activate TGF‐β1/Smad signalling, causing the EMT in fructose‐exposed BRL‐3A cells. Polydatin antagonized ZEB1 nuclear translocation to up‐regulate miR‐203, subsequently blocked survivin‐activated TGF‐β1/Smad signalling, which were consistent with its protection against fructose‐induced EMT and liver fibrosis. These results suggest that ZEB1 nuclear translocation may play an essential role in fructose‐induced EMT in liver fibrosis by targeting survivin to activate TGF‐β1/Smad signalling. The suppression of ZEB1 nuclear translocation by polydatin may be a novel strategy for attenuating the EMT in liver fibrosis associated with high fructose diet. [ABSTRACT FROM AUTHOR]

Ischaemia/reperfusion (I/R)‐induced hepatic injury is regarded as a main reason of hepatic failure after transplantation or lobectomy. The current study aimed to investigate how the opioid analgesic remifentanil treatment affects I/R‐induced hepatic injury and explore the possible mechanisms related to HIF1α. Initially, an I/R‐induced hepatic injury animal model was established in C57BL/6 mice, and an in vitro hypoxia‐reoxygenation model was constructed in NCTC‐1469 cells, followed by remifentanil treatment and HIF1α silencing treatment. The levels of blood glucose, lipids, alanine transaminase (ALT) and aspartate transaminase (AST) in mouse serum were measured using automatic chemistry analyser, while the viability and apoptosis of cells were detected using CCK8 assay and flow cytometry. Our results revealed that mice with I/R‐induced hepatic injury showed higher serum levels of blood glucose, lipids, ALT and AST and leukaemia inhibitory factor (LIF) expression, and lower HIF1α and ZEB1 expression (P <.05), which were reversed after remifentanil treatment (P <.05). Besides, HIF1α silencing increased the serum levels of blood glucose, lipids, ALT and AST (P <.05). Furthermore, hypoxia‐induced NCTC‐1469 cells exhibited decreased HIF1α and ZEB1 expression, reduced cell viability, as well as increased LIF expression and cell apoptosis (P <.05), which were reversed by remifentanil treatment (P <.05). Moreover, HIF1α silencing down‐regulated ZEB1 expression, decreased cell viability, and increased cell apoptosis (P <.05). ZEB1 was identified to bind to the promoter region of LIF and inhibit its expression. In summary, remifentanil protects against hepatic I/R injury through HIF1α and downstream effectors. [ABSTRACT FROM AUTHOR]

Hepatocellular carcinoma (HCC) is a common disease worldwide. Accumulating reports have evidenced the internal connection between epithelial‐mesenchymal transition (EMT) and cancer stem cells (CSCs), as well as their significance in metastasis and post–operative recurrence. In this study, we investigated an interesting ubiquitin‐proteasome pathway associated pseudogene of AOC4, also known as UPAT, and showed that it was downregulated in 39.78% (37/93) of patients with hepatitis B virus (HBV)‐related HCC. Downregulation of UPAT was associated with multiple worse clinicopathological parameters, as well as decreased recurrence‐free survival (RFS). In vitro and in vivo assays found that overexpression of UPAT significantly suppressed cellular migration, invasion, EMT processes, and CSC properties. Mechanistic studies showed that UPAT promoted ZEB1 degradation via a ubiquitin‐proteasome pathway and, in contrast, ZEB1 transcriptionally suppressed UPAT by binding to multiple E‐box (CACCTG) elements in the promoter region. Moreover, UPAT was negatively correlated with ZEB1 protein in HCC tissues, their combined expression discriminated RFS outcomes for patients with HBV‐related HCC. These data on the UPAT‐ZEB1 circuit‐mediated pathway will further knowledge on EMT and CSCs, and may help to develop novel therapeutic approaches for the prevention of HCC metastasis. [ABSTRACT FROM AUTHOR]

Background: Bladder cancer (BC) is a common urinary neoplasm with high incidence worldwide. Long noncoding RNA zinc ribbon domain containing 1 antisense RNA 1 (ZNRD1‐AS1) has been reported to be upregulated in BC. However, the exact role of ZNRD1‐AS1 as well as its mechanism remains poorly understood. Methods: Zinc ribbon domain containing 1 antisense RNA 1, and its potential downstream genes microRNA‐194 (miR‐194) and zinc finger E‐box binding homeobox 1 (ZEB1) levels were detected via quantitative real‐time polymerase chain reaction or western blot. Cell proliferation, migration, invasion, and epithelial‐mesenchymal transition (EMT) were detected to assess the influences of ZNRD1‐AS1, miR‐194 and ZEB1 on BC cells by colony formation, cell counting kit‐8 (CCK‐8), transwell analysis or western blot. The relationship between miR‐194 and ZNRD1‐AS1 or ZEB1 was analyzed by luciferase activity analysis. The xenograft experiment was performed to assess the function of ZNRD1‐AS1 in vivo. Results: Zinc ribbon domain containing 1 antisense RNA 1level was upregulated in BC. ZNRD1‐AS1 silence repressed proliferation, migration, invasion and EMT in BC cells. MiR‐194 was identified as a target of ZNRD1‐AS1, and miR‐194 upregulation repressed proliferation, migration, invasion, and EMT by ZNRD1‐AS1 sponging. ZEB1 was targeted via miR‐194 and its interference impeded proliferation, migration, invasion, and EMT. Moreover, ZNRD1‐AS1 regulated ZEB1 expression via miR‐194. Besides, inhibition of ZNRD1‐AS1 attenuated tumor growth by miR‐194/ZEB1 axis in vivo. Conclusion: Knockdown of ZNRD1‐AS1 suppressed BC cell development in vitro and in vivo via targeting miR‐194 to regulate ZEB1, indicating a novel avenue for treatment of BC. [ABSTRACT FROM AUTHOR]

Transforming growth factor β (TGFβ) is a prominent cytokine that promotes tumor progression by activating epithelial‐to‐mesenchymal transition (EMT). This study indicated that TGFβ exerted metastasis by inducing zinc finger E‐box binding homeobox 1 (ZEB1) and a long noncoding RNA, LINC00273, expressions in A549 cells. Knocking down LINC00273 diminished TGFβ induced ZEB1 expression as well as metastasis. Mechanistically, LINC00273 acted as a molecular sponge of microRNA (miR)‐200a‐3p which liberate ZEB1 to perform its prometastatic functions. LINC00273 knockdown and miR200a3p mimic transfection of A549 cells were used for validating the link between TGFβ and LINC00273 induced metastasis. RNA pulldown and luciferase assay were performed to establish mir200a‐3p‐LINC00273 interaction. High expressions of LINC00273, TGFβ, and ZEB1 with concurrent low miR200a‐3p expression had been verified in vivo and in patient samples. Overall, LINC00273 promoted TGFβ‐induced lung cancer EMT through miR‐200a‐3p/ZEB1 feedback loop and may serve as a potential target for therapeutic intervention in lung cancer metastasis. [ABSTRACT FROM AUTHOR]

Invasion, metastasis and therapy resistance are the major cause of cancer‐associated deaths, and the EMT‐inducing transcription factor ZEB1 is a crucial stimulator of these processes. While work on ZEB1 has mainly focused on its role as a transcriptional repressor, it can also act as a transcriptional activator. To further understand these two modes of action, we performed a genome‐wide ZEB1 binding study in triple‐negative breast cancer cells. We identified ZEB1 as a novel interactor of the AP‐1 factors FOSL1 and JUN and show that, together with the Hippo pathway effector YAP, they form a transactivation complex, predominantly activating tumour‐promoting genes, thereby synergising with its function as a repressor of epithelial genes. High expression of ZEB1, YAP, FOSL1 and JUN marks the aggressive claudin‐low subtype of breast cancer, indicating the translational relevance of our findings. Thus, our results link critical tumour‐promoting transcription factors: ZEB1, AP‐1 and Hippo pathway factors. Disturbing their molecular interaction may provide a promising treatment option for aggressive cancer types. Synopsis: How the EMT‐transcription factor ZEB1 stimulates cancer cell plasticity in context‐dependent manner is unclear. Here, genome‐wide analyses highlight AP‐1 and Hippo effector YAP as novel binding partners of ZEB1, cooperating in driving tumour‐promoting gene expression in mammary malignancies. ZEB1 and AP‐1 factor JUN co‐occupy DNA‐targets in human TNBC cells.ZEB1 directly interacts with AP‐1 factors JUN and FOSL1.ZEB1 mediates dual transcriptional function, being repressive on its own, but trans‐activating together with AP‐1 and YAP.ZEB1, AP‐1 and YAP correlate with worse survival in claudin‐low aggressive breast cancer. [ABSTRACT FROM AUTHOR]

Long noncoding RNA (lncRNA) have emerged as crucial regulators for a myriad of biological processes, and perturbations in their cellular expression levels have often been associated with cancer pathogenesis. In this study, we identified AATBC (apoptosis‐associated transcript in bladder cancer, LOC284837) as a novel lncRNA. AATBC was found to be highly expressed in nasopharyngeal carcinoma (NPC), and increased AATBC expression was associated with poor survival in patients with NPC. Furthermore, AATBC promoted migration and invasion of NPC cells in vitro, as well as metastasis in vivo. AATBC upregulated the expression of the desmosome‐associated protein pinin (PNN) through miR‐1237‐3p sponging. In turn, PNN interacted with the epithelial–mesenchymal transition (EMT) activator ZEB1 and upregulated ZEB1 expression to promote EMT in NPC cells. Collectively, our results indicate that AATBC promotes NPC progression through the miR‐1237‐3p–PNN–ZEB1 axis. Our findings indicate AATBC as a potential prognostic biomarker or therapeutic target in NPC. [ABSTRACT FROM AUTHOR]

Circular RNAs (circRNAs) function as modulators of microRNAs (miRNAs) and are often involved in cancer progression. This study aims to investigate the underlying mechanism by which circRNA hsa‐circ‐000684 promotes the progression of gastric cancer (GC). Expression of hsa‐circ‐000684 and that of ZEB1 mRNA were elevated while microRNA‐186 (miR‐186) expression was downregulated in GC cell lines and clinical tissues. In addition, the effects of hsa‐circ‐000684 on the proliferation, migration, invasion, and tube formation of GC cells were examined through gain‐and loss‐of‐function experiments. Furthermore, we introduced tumor xenografts into nude mice to better understand these effects in vivo. Either knockdown of hsa‐circ‐000684 or upregulation of miR‐186 inhibited GC cell proliferation, migration, invasion, and tube formation in vitro, and reduced the xenograft tumor growth in nude mice. Moreover, we found that hsa‐circ‐000684 and ZEB1 directly bound to miR‐186. Hsa‐circ‐000684 increased the expression of ZEB1 by binding to miR‐186. The tumor suppressive effects of hsa‐circ‐000684 knockdown were reversed by inhibition of miR‐186. Collectively, our data show that hsa‐circ‐000684 reduces the miR‐186 expression which leads to an increase in the ZEB1 expression and, consequently, promotion of GC progression. [ABSTRACT FROM AUTHOR]

We previously revealed that tumor cell‐derived angiopoietin‐like protein 2 (ANGPTL2) accelerates the metastatic capacity of tumors in an autocrine/paracrine manner by activating tumor cell motility and invasiveness and the epithelial‐mesenchymal transition. However, the effects of ANGPTL2 on cancer cell glycolytic metabolism, which is a hallmark of tumor cells, are unknown. Here we report evidence supporting a role for tumor cell‐derived ANGPTL2 in establishing a preference for glycolytic metabolism. We report that a highly metastatic lung cancer cell subline expressing abundant ANGPTL2 showed upregulated expression of the glucose transporter GLUT3 as well as enhanced glycolytic metabolism relative to a less metastatic parental line. Most notably, ANGPTL2 overexpression in the less metastatic line activated glycolytic metabolism by increasing GLUT3 expression. Moreover, ANGPTL2 signaling through integrin α5β1 increased GLUT3 expression by increasing transforming growth factor‐β (TGF‐β) signaling and expression of the downstream transcription factor zinc finger E‐box binding homeobox 1 (ZEB1). Conversely, ANGPTL2 knockdown in the highly metastatic subline decreased TGF‐β1, ZEB1, and GLUT3 expression and antagonized glycolytic metabolism. In primary tumor cells from patients with lung cancer, ANGPTL2 expression levels correlated with GLUT3 expression. Overall, this work suggests that tumor cell‐derived ANGPTL2 accelerates activities associated with glycolytic metabolism in lung cancer cells by activating TGF‐β‐ZEB1‐GLUT3 signaling. [ABSTRACT FROM AUTHOR]

Tumour invasion is closely related to the prognosis and recurrence of glioblastoma multiforme and partially attributes to epithelial‐mesenchymal transition. Long intergenic non‐coding RNA 00511 (LINC00511) plays a pivotal role in tumour; however, the role of LINC00511 in GBM, especially in the epigenetic molecular regulation mechanism of EMT, is still unclear. Here, we found that LINC00511 was up‐regulated in GBM tissues and relatively high LINC00511 expression predicted poorer prognosis. Moreover, ectopic LINC00511 enhanced GBM cells proliferation, EMT, migration and invasion, whereas LINC00511 knockdown had the opposite effects. Mechanistically, we confirmed that ZEB1 acted as a transcription factor for LINC00511 in GBM cells. Subsequently, we found that LINC00511 served as a competing endogenous RNA that sponged miR‐524‐5p to indirectly regulate YB1, whereas, up‐regulated YB1 promoted ZEB1 expression, which inversely facilitated LINC00511 expression. Finally, orthotopic xenograft models were performed to further demonstrate the LINC00511 on GBM tumorigenesis. This study demonstrates that a LINC00511/miR‐524‐5p/YB1/ZEB1 positive feedback loop provides potential therapeutic targets for GBM progression. [ABSTRACT FROM AUTHOR]

Previous studies have implicated the attractive and promising role of miR‐590‐3p to restore the cardiac function following myocardial infarction (MI). However, the molecular mechanisms for how miR‐590‐3p involves in cardiac fibrosis remain largely unexplored. Using human cardiac fibroblasts (HCFs) as the cellular model, luciferase report assay, mutation, EdU assay and transwell migration assay were applied to investigate the biological effects of miR‐590‐3p on the proliferation, differentiation, migration and collagen synthesis of cardiac fibroblasts. We found that miR‐590‐3p significantly suppressed cell proliferation and migration of HCFs. The mRNA and protein expression levels of α‐SMA, Col1A1 and Col3A were significantly decreased by miR‐590‐3p. Moreover, miR‐590‐3p directly targeted at the 3'UTR of ZEB1 to repress the translation of ZEB1. Interfering with the expression of ZEB1 significantly decreased the cell proliferation, migration activity, mRNA and protein expressions of α‐SMA, Col1A1 and Col3A. Furthermore, the expressions of miR‐590‐3p and ZEB1 were identified in infarct area of MI model in pigs. Collectively, miR‐590‐3p suppresses the cell proliferation, differentiation, migration and collagen synthesis of cardiac fibroblasts by targeting ZEB1. These works will provide useful biological information for future studies on potential roles of miR‐590‐3p as the therapeutic target to recover cardiac function following MI. [ABSTRACT FROM AUTHOR]

Multiple studies have unveiled that long non‐coding RNAs (lncRNAs) play a pivotal role in tumour progression and metastasis. However, the biological role of lncRNA ZEB1‐AS1 in oesophageal squamous cell carcinoma (ESCC) remains under investigation, and thus, the current study was to investigate the functions of ZEB1‐AS1 in proliferation and invasion of ESCC. Here, we discovered that ZEB1‐AS1 and ZEB1 were markedly up‐regulated in ESCC tissues and cells relative to their corresponding normal control. ZEB1‐AS1 and ZEB1 overexpressions were both related to TNM staging and lymph node metastasis as well as poor prognosis in ESCC. The hypomethylation of ZEB1‐AS1 promoter triggered ZEB1‐AS1 overexpression in ESCC tissues and cells. In addition, ZEB1‐AS1 knockdown mediated by siRNA markedly suppressed the proliferation and invasion in vitro in EC9706 and TE1 cells, which was similar with ZEB1 siRNA treatment, coupled with EMT alterations including the up‐regulation of E‐cadherin level as well as the down‐regulation of N‐cadherin and vimentin levels. Notably, ZEB1‐AS1 depletion dramatically down‐regulated ZEB1 expression in EC9706 and TE1 cells, and ZEB1 overexpression obviously reversed the inhibitory effects of proliferation and invasion triggered by ZEB1‐AS1 siRNA. ZEB1‐AS1 shRNA evidently inhibited tumour growth and weight, whereas ZEB1 elevation partly recovered the tumour growth in ESCC EC9706 and TE1 xenografted nude mice. In conclusion, ZEB1‐AS1 overexpression is tightly involved in the development and progression of ESCC, and it exerts the antitumour efficacy by regulating ZEB1 level in ESCC. [ABSTRACT FROM AUTHOR]

Objective: Epithelial–mesenchymal transition (EMT) is important in the tooth development and tumor invasion. We investigated the effect of interleukin‐8 (IL‐8) on the EMT process in primary‐cultured ameloblastoma tumor cells (AM‐P) and ameloblastoma immortalized tumor cells (AM‐L) and its underlying mechanism. Methods: IL‐8 levels in ameloblastomas were detected by immunofluorescence staining and ELISA. AM‐P cells and AM‐L cells were stimulated with IL‐8, and EMT transcription factors, total β‐catenin and phosphorylated‐β‐catenin (p‐β‐catenin) levels were determined by Western blot analysis and immunofluorescence staining. β‐catenin siRNA was used to knockdown β‐catenin expression in AM‐P cells and AM‐L cells stimulated with IL‐8. Results: IL‐8 was highly expressed in the solid ameloblastomas. IL‐8 promoted the EMT process in ameloblastoma tumor cells in vitro, as evidenced by decreased E‐cadherin and increased vimentin, twist and zeb1 levels. IL‐8 also increased total β‐catenin and p‐β‐catenin expression in ameloblastoma tumor cells, and β‐catenin knockdown partially inhibited the EMT process in tumor cells, as evidenced by increased E‐cadherin, and decreased vimentin and zeb1 levels. Conclusions: IL‐8 could promote EMT in ameloblastoma tumor cells by activating β‐catenin and its downstream transcription factor zeb1. [ABSTRACT FROM AUTHOR]

Diabetic nephropathy (DN) is a kind of microvascular complications of diabetes. Long noncoding RNAs (lnRNAs) can participate in the development of various diseases, including DN. However, the function of lncRNA NEAT1 is unclear. In our present study, we reported that NEAT1 was significantly increased in streptozotocin‐induced DN rat models and high‐glucose‐induced mice mesangial cells. We observed that knockdown of NEAT1 greatly inhibited renal injury of DN rats. Meanwhile, downregulation of NEAT1‐modulated extracellular matrix (ECM) proteins (ASK1, fibronectin, and TGF‐β1) expression and epithelial–mesenchymal transition (EMT) proteins (E‐cadherin and N‐cadherin) in vitro. Previously, miR‐27b‐3p has been reported to be involved in diabetes. Here, miR‐27b‐3p was decreased in DN rats and high‐glucose‐induced mice mesangial cells. The direct correlation between NEAT1 and miR‐27b‐3p was validated using the dual‐luciferase reporter assay and RNA immunoprecipitation experiments. In addition, zinc finger E‐box binding homeobox 1 (ZEB1), which has been identified in the process of EMT clearly contributes to EMT progression. ZEB1 was predicted as a target of miR‐27b‐3p and overexpression of miR‐27b‐3p dramatically repressed ZEB1 expression. Therefore, our data implied the potential role of NEAT1 in the fibrogenesis and EMT in DN via targeting miR‐27b‐3p and ZEB1. [ABSTRACT FROM AUTHOR]

Neuroblastoma (NB) is one of the most common malignant tumors derived from pluripotent cells of the neural crest. Nodal is an important embryonic morphogen which can re‐express in cancer cells. The roles of Nodal in the progression of NB are not illustrated. Our present study reveals that Nodal is upregulated in NB cells and tissues. Targeted inhibition of Nodal can suppress the in vitro migration and invasion of NB cells while increase its chemo‐sensitivity to doxorubicin (Dox) treatment. Nodal positively regulates the expression of Zeb1, one well‐known transcription factors of epithelial to mesenchymal transition (EMT) of cancer cells. Knockdown of Zeb1 can attenuate Nodal‐induced malignancy of NB cells. Mechanistically, Nodal increases the protein stability of Zeb1 while has no effect on its mRNA expression. It is due to that Nodal can increase the expression of Ataxia telangiectasia mutated kinase (ATM), which can phosphorylate and stabilize Zeb1 in cancer cells. Collectively, our data revealed that Nodal can increase the malignancy of NB cells via increasing the expression of Zeb1. It suggests that targeted inhibition of Nodal might be a potential therapy approach for NB treatment. © 2019 BioFactors, 45(3):355–363, 2019 [ABSTRACT FROM AUTHOR]

Long noncoding RNAs (lncRNAs) have drawn increasing attention because of the role which they play in various diseases, including osteosarcoma. So far, the function and mechanism of HOTAIR in osteosarcoma are unclear. In our study, we observed that HOTAIR was elevated accompanied with a decrease of miR‐217 and an increase of ZEB1 in human osteosarcoma cells including U2OS, MG63, Saos‐2, and SW1353 compared with human osteoblast cell line hFOB. In addition, the subsequent functional assay exhibited that silencing HOTAIR could significantly repress osteosarcoma cell growth, migration, invasion, and induce cell apoptosis capacity, which indicated that HOTAIR exerted an oncogenic role in osteosarcoma. Moreover, it was revealed by using bioinformatics analysis that HOTAIR can be targeted by microRNA‐217 (miR‐217). miR‐217 has been recognized as a crucial tumor suppressive gene in cancers. We verified that mimics of miR‐217 were able to suppress the osteosarcoma development. Furthermore, real‐time quantitative PCR showed that HOTAIR siRNA increased miR‐217 expression. Besides these, ZEB1 was identified as a downstream gene of miR‐217 and we found that HOTAIR can mediate osteosarcoma progress by upregulating ZEB1 expression via acting as a competitive endogenous RNA (ceRNA) via miR‐217. Taken these together, our findings in this study indicated that HOTAIR/miR‐217/ZEB1 axis, as a novel research point can provide new insights into molecular mechanism of osteosarcoma development. [ABSTRACT FROM AUTHOR]

Background: Capn4 and ZEB1 play important roles in the metastasis of several types of cancer. However, the roles and relationship of Capn4 and ZEB1 in esophageal squamous cell carcinoma (ESCC) remain unclear. Methods: ESCC tumor tissues and corresponding normal esophageal epithelial tissues were obtained from 86 patients undergoing resection surgery at the Department of General Surgery, First Affiliated Hospital of Chinese PLA General Hospital from 2012 to 2017. Cell migration and invasion were examined via quantitative real‐time PCR and Western blot assay. Results: Our results indicate that both Capn4 and ZEB1 are significantly upregulated in ESCC tissues compared to corresponding adjacent tissues, and a positive correlation between expression and associated malignant characteristics was found. Silencing of Capn4 expression markedly inhibited ESCC invasion and metastasis in vitro and in vivo, and was accompanied by decreased ZEB1 expression. Furthermore, the anti‐metastasis role of Capn4 silencing was reversed by ZEB1 overexpression, whereas knockdown of ZEB1 decreased ESCC metastasis driven by the upregulation of Capn4. Mechanistically, Capn4 regulated ZEB1 expression via activation of the Wnt/β‐catenin signaling pathway in ESCC cells. Conclusion: Overall, our results show that enhanced Capn4 expression activates the Wnt/β‐catenin signaling pathway, resulting in increased ZEB1 expression and the promotion of ESCC cell metastasis. [ABSTRACT FROM AUTHOR]

Background: There is abundant evidence to indicate that HBXIP functions as an oncoprotein and transcription co‐activator during the development and promotion of cancers. In multiple cancers, ZEB1 serves as a transcription activator to regulate gene expression. We explored the roles of ZEB1 in HBXIP‐induced breast cancer growth. Methods: HBXIP regulation of ZEB1 was evaluated by reverse transcription PCR and immunoblotting. The stimulation of ZEB1 promoter by HBXIP and/or Sp1 was tested using luciferase reporter gene analysis. The alteration of cell proliferation mediated by HBXIP‐induced ZEB1 was tested using methyl‐thiazolyl‐tetrazolium and 5‐Ethynyl‐2′‐deoxyuridine (EdU) incorporation analysis. ZEB1 and HBXIP expression in human breast cancer tissues was analyzed using quantitative real‐time PCR. The relationship between HBXIP and ZEB1 was confirmed by Pearson's correlation coefficient. Results: We observed dose‐dependent upregulation of ZEB1 by HBXIP in breast cancer cells. HBXIP can activate the ZEB1 promoter by interacting with transcription factor Sp1. Cell viability and EdU incorporation analysis showed that HBXIP could drive cell proliferation by enhancing ZEB1 in breast cancer. Using quantitative real‐time PCR, ZEB1 overexpression and a positive relationship between ZEB1 and HBXIP were observed in clinical breast cancer samples. Conclusion: Oncogenic HBXIP controls the transcription regulation of ZEB1 by co‐activating Sp1, thereby accelerating breast cancer growth. [ABSTRACT FROM AUTHOR]

Breast cancer is a kind of common female cancers. Increasing evidence has exhibited that lncRNAs exert a crucial role in breast cancer. So far, the mechanism of lncRNAs in breast cancer is still not well established. In our current study, we focused on the biological role of lncRNA Nuclear Enriched Abundant Transcript 1 (NEAT1) in breast cancer. We observed that NEAT1 levels were significantly increased in human breast cancer cells including MCF‐7, MDA‐MB‐453, MDA‐MB‐231, and SKBR3 cells compared to normal mammary epithelial cells MCF‐10A while miR‐448 was decreased. We found that downregulation of NEAT1 was able to inhibit the growth of breast cancer cells and miR‐448 mimic exerted the similar function. Bioinformatics analysis and dual luciferase reporter assays confirmed the negative correlation between NEAT1 and miR‐448 in vitro. In addition, ZEB1 was predicted as a novel mRNA target of miR‐448. Overexpression of NEAT1 can induce breast cancer cell growth, migration, and invasion by inhibiting miR‐448 and upregulating ZEB1. It was demonstrated that NEAT1 can increase ZEB1 levels while miR‐448 mimic can repress ZEB1. It was speculated in our study that NEAT1 can serve as a competing endogenous lncRNA (ceRNA) to modulate ZEB1 by sponging miR‐448 in breast cancer. To conclude, we uncovered that NEAT1 participated in breast cancer progression by regulating miR‐448 and ZEB1. NEAT1 can be provided as a vital biomarker in breast cancer diagnosis and treatment therapy. [ABSTRACT FROM AUTHOR]

Abstract: Pancreatic cancer (PC) is one of the most malign human cancers, with its underlying molecular mechanisms largely unknown. In this work, we investigated the mechanistic role of protein arginine methyltransferase 1 (PRMT1) gene in PC. Expression of PRMT1 in immortal PC cell lines and clinical human PC tumors was evaluated by quantitative real‐time polymerase chain reaction (qRT‐PCR) and western blot. In PANC‐1 and SW1990 cells, PRMT1 was either downregulated by lentiviral‐mediated short hairpin RNA (shRNA) or upregulated by overexpression plasmid. The effects of PRMT1 downregulation or upregulation on PC proliferation and invasion in vitro, and xenograft in vivo, were evaluated. Gene expression of PRMT1 downstream target, zinc finger E‐box binding homeobox 1 (ZEB1) was measured in PRMT1‐downregulated PC cells. ZEB1 was also upregulated in PRMT1‐downregulated PC cells to evaluate its functional role in PRMT1‐mediated regulation in PC. PRMT1 was downregulated in both PC cell lines and human tumors. PRMT1 downregulation in PANC‐1 and SW1990 cells significantly suppressed cancer proliferation and invasion in vitro and xenograft in vivo. However, PRMT1 overexpression did not have function impact in PC cells. ZEB1 gene expression was suppressed in PRMT1‐downregulated PC cells. Subsequently, overexpressing ZEB1 reversed the antitumor effects of PRMT1 downregulation in PC cells. PRMT1 was aberrantly upregulated in PC. PRMT1 inhibition, possibly inversely acting through ZEB1, might be an effective molecular intervention to inhibit PC growth and invasion. © 2018 IUBMB Life, 70(10):1032–1039, 2018 [ABSTRACT FROM AUTHOR]