MicroRNA-33a-5p suppresses esophageal squamous cell carcinoma progression via regulation of lncRNA DANCR and ZEB1.

Increasing evidence displays that microRNAs (miRNAs) participate in the development of various human malignancies, including esophageal squamous cell carcinoma (ESCC). MicroRNA-33a-5p (miR-33a-5p) has recently been reported to function as a tumor suppressor in many human cancers. However, the expression and role of miR-33a-5p in ESCC remains largely unknown. Herein, we discovered that miR-33a-5p was down-regulated in both ESCC tissues and cell lines, compared with their normal counterparts, and decreased expression of miR-33a-5p was found to be closely associated with poor patient prognosis of ESCC. Moreover, functional experiments revealed that up-regulation of miR-33a-5p inhibited cell proliferation and metastasis of ESCC cells. In addition, the expression level of miR-33a-5p was found to be negatively correlated with the long non-coding RNA (lncRNA) differentiation antagonizing non-protein coding RNA (DANCR), in both ESCC tissues and cell lines. Furthermore, zinc-finger-enhancer binding protein 1 (ZEB1) was predicted and confirmed to be a direct target of miR-33a-5p in ESCC. Further mechanistic investigation indicated that DANCR may function as a competing endogenous RNA (ceRNA) to sponge miR-33a-5p, and thereby up-regulate ZEB1 expression in ESCC. This study highlights the functions of miR-33a-5p in the progression of ESCC and suggests that the DANCR/miR-33a-5p/ZEB1 axis may be a potential prognostic and therapeutic target.

Zhang C ，Wang L ，Yang J ，Fu Y ，Li H ，Xie L ，Cui Y ... -  《-》

CCL18-induced HOTAIR upregulation promotes malignant progression in esophageal squamous cell carcinoma through the miR-130a-5p-ZEB1 axis.

Accumulating evidence indicates that CCL18 and the long non-coding RNA, HOTAIR, have critical roles in cancer progression and metastasis, but the correlation between CCL18 and HOTAIR in esophageal squamous cell carcinoma (ESCC) and their downstream molecular mechanisms remain unclear. Overexpression of CCL18 in ESCC tissues was associated with a worse survival in patients with ESCC. CCL18 enhanced the invasiveness of ESCC cells in a dose-dependent manner, whereas CCL18 knockdown inhibited their invasiveness. In particular, CCL18 expression was positively associated with HOTAIR expression in ESCC tissues. Furthermore, CCL18 upregulated the expression of HOTAIR, and knockdown of HOTAIR alleviated the CCL18-induced invasiveness of ESCC cells. HOTAIR may act as a competing endogenous RNA and could effectively becoming a sponge for miR-130a-5p, thereby modulating the derepression of ZEB1 and promoting epithelial-mesenchymal transition in ESCC. Our study suggests that CCL18 contributes to the malignant progression of esophageal cancer by upregulating HOTAIR expression. HOTAIR overexpression may promote tumor invasiveness and progression in ESCC, given that HOTAIR functions as a miR-130a-5p sponge, positively regulating ZEB1. This provides new therapeutic targets for early diagnosis and treatment of ESCC.

Wang W ，Wu D ，He X ，Hu X ，Hu C ，Shen Z ，Lin J ，Pan Z ，He Z ，Lin H ，Wang M ... -  《-》

LncRNA ZEB1-AS1 down-regulation suppresses the proliferation and invasion by inhibiting ZEB1 expression in oesophageal squamous cell carcinoma.

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.

Zhao Y ，Wang N ，Zhang X ，Liu H ，Yang S ... -  《-》

Long non-coding RNA DANCR facilitates glioma malignancy by sponging miR-33a-5p.

Yang JX ，Sun Y ，Gao L ，Meng Q ，Yang BY ... -  《NEOPLASMA》

Long Non-coding RNA X-Inactive Specific Transcript Promotes Esophageal Squamous Cell Carcinoma Progression via the MicroRNA 34a/Zinc Finger E-box-Binding Homeobox 1 Pathway.

The long non-coding RNA X-inactive specific transcript (XIST) plays a crucial role in transcriptional silencing of the X chromosome. Zinc finger E-box-binding homeobox 1 (ZEB1) is a transcription factor involved in epithelial-mesenchymal transition (EMT) regulation. This study aimed to investigate the impact of XIST on esophageal squamous cell carcinoma (ESCC) progression and its underlying mechanism involving the miR-34a/ZEB1/E-cadherin/EMT pathway. XIST and ZEB1 expression were analyzed using quantitative PCR and immunohistochemistry. XIST knockdown was achieved in KYSE150 ESCC cells using siRNA or shRNA lentivirus transfection. Proliferation, migration, and invasion abilities were assessed, and luciferase reporter assays were performed to confirm XIST-miR-34a-ZEB1 interactions. In vivo ESCC growth was evaluated using a xenograft mouse model. XIST and ZEB1 were upregulated in tumor tissues, correlating with metastasis and reduced survival. XIST knockdown inhibited proliferation, migration, and invasion of KYSE150 cells. It decreased ZEB1 expression, increased E-cadherin and miR-34a levels. Luciferase reporter assays confirmed miR-34a binding to XIST and ZEB1. XIST knockdown suppressed xenograft tumor growth. XIST promotes ESCC progression via the miR-34a/ZEB1/E-cadherin/EMT pathway. Targeting the XIST/miR-34a/ZEB1 axis holds therapeutic potential and serves as a prognostic biomarker in ESCC.

Guo B ，He M ，Ma M ，Tian Z ，Jin J ，Tian G ... -  《-》