MEF2A transcriptionally upregulates the expression of ZEB2 and CTNNB1 in colorectal cancer to promote tumor progression.

Colorectal cancer (CRC) is one of the leading cancers worldwide, accounting for high morbidity and mortality. The mechanisms governing tumor growth and metastasis in CRC require detailed investigation. The results of the present study indicated that the transcription factor (TF) myocyte enhancer factor 2A (MEF2A) plays a dual role in promoting proliferation and metastasis of CRC by inducing the epithelial-mesenchymal transition (EMT) and activation of WNT/ß-catenin signaling. Aberrant expression of MEF2A in CRC clinical specimens was significantly associated with poor prognosis and metastasis. Functionally, MEF2A directly binds to the promoter region to initiate the transcription of ZEB2 and CTNNB1. Simultaneous activation of the expression of EMT-related TFs and Wnt/ß-catenin signaling by MEF2A overexpression induced the EMT and increased the frequency of tumor formation and metastasis. The present study identified a new critical oncogene involved in the growth and metastasis of CRC, providing a potential novel therapeutic target for CRC intervention.

TCF4 promotes colorectal cancer drug resistance and stemness via regulating ZEB1/ZEB2 expression.

The present study aims to investigate the roles of TCF4 and its underlying mechanism in colorectal cancer (CRC). Doxorubicin-resistant DLD-1 (DLD1 DR), TCF4 overexpression, and TCF4 knockdown cell lines were constructed. A flow cytometer was used to analyze frequencies of CD133+ cell in the DLD1 and DLD1 DR cells. Quantitative real-time PCR (qPCR) was used to determine the expressions of cancer stem cell (CSC) makers. Stemness of CRC cells were determined using tumorsphere formation assay. The correlation between TCF4 and ZEB1/ZEB2 were determined using public data from The Cancer Genome Atlas (TCGA) datasets. ZEB1/ZEB2 overexpression cell lines were constructed and cell viabilities were then determined using MTT and colony formation assays. TCF4 overexpression promoted proliferation of CRC cell lines and relative expressions of TCF4 were significantly increased in the DLD1 DR cells. TCF4 overexpression promoted CRC cell doxorubicin resistance, whereas TCF4 knockdown significantly decreased doxorubicin resistance. Additionally, TCF4 overexpression also significantly increased frequencies of CSC cells, expressions of CSC markers, and CRC ability to form tumorsphere. Furthermore, TCF4 promoted ZEB1 and ZEB2 expression, leading to CRC proliferation and doxorubicin resistance. TCF4 promoted CRC doxorubicin resistance and stemness by regulating expressions of ZEB1 and ZEB2.

Expression of Selected Epithelial-Mesenchymal Transition Transcription Factors in Endometrial Cancer.

Endometrial cancer (EC) is the most common gynecologic malignancy in developed countries. The aim of this study was to analyze the expression of SNAIL, SLUG, TWIST1, TWIST2, ZEB1, and ZEB 2 in primary tumor and the correlation with morphological and clinical characteristics of EC. The study included 158 patients with EC after surgical treatments: total hysterectomy and lymphadenectomy. The percentages of EC specimens testing positively for the EMT transcription factors were 84.5% for SNAIL, 92.2% for SLUG, 10.9% for TWIST1, 100% for TWIST2, 89% for ZEB1, and 98% for ZEB2. The expression of SLUG in patients with FIGO stage III or IV, type II EC, myometrial invasion ≥ 50% of the uterine wall thickness, and adnexal involvement and in patients with distant metastases was significantly higher. SLUG and ZEB2 expressions were identified as significant predictors of higher FIGO stages (III or IV) on univariate analysis. The overexpression of SLUG was a significant predictor of more aggressive type II EC, myometrial invasion ≥ 50% of the uterine wall thickness, and distant metastases on both univariate and multivariate analysis. Moreover, the overexpression of SLUG and ZEB2 was shown to be significant predictors of adnexal involvement on univariate analysis. ZEB 2 overexpression was identified in multivariate analysis as another independent predictor associated with a lesser likelihood of type II EC. Both univariate and multivariate analyses demonstrated that SLUG expression was the only predictor of 5-year survival in the study group. The overexpression of SLUG was associated with a significant increase in mortality hazard on univariate analysis and was shown to be a highly significant predictor of death on multivariate analysis. Conclusions. Selected proteins of the EMT pathway play a role in endometrial carcinogenesis; SLUG and ZEB2 expressions in the primary tumor might predict clinical outcomes in EC and drive therapeutic decisions regarding adjuvant treatment in patients with this malignancy.

MicroRNA-132 directs human periodontal ligament-derived neural crest stem cell neural differentiation.

Neurogenesis is the basis of stem cell tissue engineering and regenerative medicine for central nervous system (CNS) disorders. We have established differentiation protocols to direct human periodontal ligament-derived stem cells (PDLSCs) into neuronal lineage, and we recently isolated the neural crest subpopulation from PDLSCs, which are pluripotent in nature. Here, we report the neural differentiation potential of these periodontal ligament-derived neural crest stem cells (NCSCs) as well as its microRNA (miRNA) regulatory mechanism and function in NCSC neural differentiation. NCSCs, treated with basic fibroblast growth factor and epidermal growth factor-based differentiation medium for 24 days, expressed neuronal and glial markers (ßIII-tubulin, neurofilament, NeuN, neuron-specific enolase, GFAP, and S100) and exhibited glutamate-induced calcium responses. The global miRNA expression profiling identified 60 upregulated and 19 downregulated human miRNAs after neural differentiation, and the gene ontology analysis of the miRNA target genes confirmed the neuronal differentiation-related biological functions. In addition, overexpression of miR-132 in NCSCs promoted the expression of neuronal markers and downregulated ZEB2 protein expression. Our results suggested that the pluripotent NCSCs from human periodontal ligament can be directed into neural lineage, which demonstrate its potential in tissue engineering and regenerative medicine for CNS disorders.

MicroRNAs Associated with Epithelial-Mesenchymal Transition Can Be Targeted to Inhibit Peritoneal Dissemination of Human Scirrhous Gastric Cancers.

OBJECTIVES: Scirrhous gastric cancers grow rapidly, and frequently invade the peritoneum. Such peritoneal dissemination properties markedly reduce patient survival. Thus, an effective means for inhibiting peritoneal dissemination is urgently required. METHODS: We previously established a cell line, HSC-58, from a scirrhous gastric cancer patient, and further successfully isolated a metastatic line, 58As9, in nude mice upon orthotopic inoculation. Using the lines, we examined the mechanism underlying peritoneal dissemination from the viewpoint of microRNA (miRNA) expression. RESULTS: miRNA array and qRT-PCR analysis showed that the expressions of epithelial-mesenchymal transition (EMT)-associated miRNAs such as miR-200c and miR-141 were significantly low in 58As9. Using 58As9 with stably overexpressing miR-200c, miR-141, or both, together with a luciferase reporter assay, we found that miR-200c targeted zinc finger E-box-binding homeobox 1 (ZEB1) and miR-141 targeted ZEB2. The overexpressed lines reversed the EMT status from mesenchymal to epithelial in 58As9, and significantly reduced the invasion activity and peritoneal dissemination for a significant prolongation of survival in the orthotopic tumor models in nude mice. CONCLUSIONS: EMT-associated miRNAs such as miR-200c and miR-141 and their target genes ZEB1/ZEB2 have good potential for antiperitoneal dissemination therapy in patients with scirrhous gastric cancers.

Prognostic Significance of Zinc Finger E-Box-Binding Homeobox Family in Glioblastoma.

BACKGROUND Epithelial-mesenchymal transition (EMT) is an essential progress for tumor cell invasion to both epithelial and non-epithelial cancers, and zinc finger E-box-binding homeobox 1/2 (ZEB1/2) is a well-known promoter of EMT. In glioma cell lines, both ZEB1 and ZEB2 have been demonstrated to facilitate cancer cell proliferation and invasion with experiments in vitro. However, the clinical significance of ZEB1 and ZEB2 in glioblastoma (GBM) is still controversial. MATERIAL AND METHODS We detected the expression of ZEB1 and ZEB2 in 91 cases of GBM with immunohistochemistry and investigated the correlation between clinicopathological factors and ZEB family expression with Fisher test. By univariate analysis with Kaplan-Meier test, we explored the prognostic significance of ZEB1/2 expression and the clinicopathological factors in GBM. By multivariate analysis with the Cox regression model, we identified the independent prognostic factors in GBM. RESULTS The percentages of ZEB1 high expression and ZEB2 high expression were 31.9% (29/91) and 41.9% (36/91), respectively. High expression of ZEB2 was significantly associated with lower survival rate of GBM patients (P=0.001). ZEB2, lower KPS score (P=0.004), gross total resection (P<0.001) and higher Ki67 percentage (P=0.001) were notably correlated to worse prognosis of GBM. With multivariate analysis, high expression of ZEB2 was demonstrated to be an independent prognostic factor indicating unfavorable prognosis of GBM (P=0.001, HR=3.86, and 95%CI=1.61-9.23). CONCLUSIONS High expression of ZEB2 is an independent prognostic factor predicting unfavorable prognosis of GBM, indicating that ZEB2 or its downstream proteins may be potential drug targets of GBM therapy.

Tumoral and stromal expression of Slug, ZEB1, and ZEB2 in brain metastasis.

Epithelial-to-mesenchymal transition (EMT) has an active role in the malignant progression of epithelial tumor cells. The aim of the study was to identify the existence of the EMT mechanism in brain metastasis. Tumors from 29 patients with brain metastases were assessed in terms of the immunoexpression of EMT-related factors including Slug, ZEB1, ZEB2, and E-cadherin in tumor cells and the surrounding mesenchymal stromal cells. The results were compared between primary tumors and their matched metastatic brain tumors. Analysis of tumor cell expression showed that Slug, ZEB1, or ZEB2 expression was found in more than 10% of the neoplastic cells in the metastatic lesions of 17 cases (59%) and in the primary lesions of 7 cases (24%, P=0.02). The expression level of ZEB2 was negatively correlated with that of E-cadherin (P=0.05). There were no differences in the tumoral expression levels of Slug, ZEB1, or ZEB2 among the primary organs. Analysis of stromal cell expression revealed a global increase in ZEB1 and ZEB2 expression levels with metastases (P<0.0001). Quantitative analysis confirmed that messenger RNA expression of ZEB1 and ZEB2 was elevated in metastatic lesions. The increased expression of EMT-related factors in brain metastasis was found not only in tumor cells, but also in tumor-associated stromal cells. Our results suggest that EMT-related factors play a role as a facilitator of brain metastasis.

Title Prognosis Significance of ZEB2 and TGF-ß1 as well as Other Clinical Characteristics in Epithelial Ovarian Cancer.

OBJECTIVE: This study aimed to evaluate the prognosis significance of zinc-finger E-box binding homeobox 2 (ZEB2) and transforming growth factor ß1 (TGF-ß1) as well as other clinical characteristics in epithelial ovarian cancer (EOC). METHODS: This retrospective study examined the expressions of ZEB2 and TGF-ß1 in 64 EOC specimens, 36 benign ovarian tumor specimens, and 28 normal ovarian specimens by immunohistochemistry. The correlation of the expressions of ZEB2 and TGF-ß1 was analyzed by the Spearman rank correlation analysis. The Kaplan-Meier method was used to construct crude survival curves, and the prognostic roles of ZEB2 and TGF-ß1 as well as clinical characteristics were evaluated by Cox proportional hazards regression analysis. RESULTS: The positive expression rates of ZEB2 and TGF-ß1 were increased in EOC specimens compared with benign ovarian tumor and normal ovary specimens (P < 0.05), and ZEB2 expression was positively correlated with TGF-ß1 expression (r = 0.538, P = 0.000). In addition, the overall survival rate of EOC patients was associated with the expressions of ZEB2 and TGF-ß1, age, differentiated grade, International Federation of Gynecology and Obstetrics (FIGO) stage, preoperative serum CA125 level, postoperative start time of chemotherapy, and treatment course (all P < 0.05). Multivariate Cox regression demonstrated that FIGO stage (P = 0.033), TGF-ß1 expression (P = 0.043), postoperative start time of chemotherapy (P = 0.009), and treatment course (P = 0.000) were prognostic factors for EOC. CONCLUSIONS: ZEB2 and TGF-ß1 may promote EOC progression, and FIGO stage, TGF-ß1 expression, postoperative start time of chemotherapy, and treatment course may be associated with the prognosis of EOC.

A directly negative interaction of miR-203 and ZEB2 modulates tumor stemness and chemotherapy resistance in nasopharyngeal carcinoma.

miR-203 is a tumor suppressor that is disregulated in numerous malignancies including nasopharyngeal carcinoma (NPC). However, the role of miR-203 in suppressing tumor stemness, chemotherapy resistance as well as its molecular mechanisms are unclear. In this study, we observed that miR-203 suppressed cell migration, invasion, tumor stemness, and chemotherapy resistance to cisplatin (DDP) in vitro and in vivo. miR-203 exerted these effects by targeting ZEB2 and downstream epithelial-mesenchymal transition (EMT) and tumor stemness signals. Interestingly we observed that miR-203 expression was directly suppressed by ZEB2 via targeting its promoter, which significantly reduced cell migration, invasion, tumor stemness, and chemotherapy resistance in NPC cells. Finally, we found that miR-203 was negatively correlated with ZEB2 expression in NPC tissues and tumor spheres. Our data demonstrate a directly negative feedback loop between miR-203 and ZEB2 participating in tumor stemness and chemotherapy resistance, highlighting the therapeutic potential of targeting this signal for NPC chemotherapy.