title: MicroRNA-98 and microRNA-214 post-transcriptionally regulate enhancer of zeste homolog 2 and inhibit migration and invasion in human esophageal squamous cell carcinoma.
abstract: BACKGROUND
  The enhancer of zeste homolog 2 (EZH2) was found to be overexpressed and associated with tumor metastasis in esophageal squamous cell carcinoma (ESCC). On the other hand, it was reported that miR-26a, miR-98, miR-101, miR-124, miR-138 and miR-214 could inhibit the expression of EZH2 in some tumors. However, the role of miRNAs in the regulation of EZH2 expression in human ESCC has not been documented. The aim of this study was to determine the role of these miRNAs in the regulation of tumor metastasis via EZH2 overexpression in human ESCC.
  
  
  RESULTS
  The expression of these miRNAs and EZH2 mRNA were examined by qPCR and the expression of EZH2 protein was detected by western blot. The role of these miRNAs in migration and invasion was studied in ESCC cell line (Eca109) transfected with miRNA mimics or cotransfected with miRNA mimics and pcDNA-EZH2 plasmid (without the 3'-UTR of EZH2). Through clinical investigation, we found that miR-98 and miR-214 expression was significantly lower in ESCC tissues than in matched normal tissues, and the expression level of miR-98 and miR-214 was inversely correlated to EZH2 protein expression and the clinical features such as pathological grade, tumor stage and lymph node metastasis in ESCC. In Eca109 cells, overexpression of miR-98 and miR-214 significantly inhibited the migration and invasion of ESCC cells, which was reversed by transfection of EZH2.
  
  
  CONCLUSIONS
  These findings suggest that decreased expression of miR-98 and miR-214 might promote metastasis of human ESCC by inducing accumulation of EZH2 protein.
authors.affiliation: Institute of Cardiothoracic Surgery, Changhai Hospital, 168, Changhai Rd, Shanghai, PR China.
authors.forename: Sheng-Dong
authors.initials: SD
authors.lastname: Huang
authors.forename: Yang
authors.initials: Y
authors.lastname: Yuan
authors.forename: Chong-Wen
authors.initials: CW
authors.lastname: Zhuang
authors.forename: Bai-Ling
authors.initials: BL
authors.lastname: Li
authors.forename: De-Jun
authors.initials: DJ
authors.lastname: Gong
authors.forename: Shu-Gang
authors.initials: SG
authors.lastname: Wang
authors.forename: Zhi-Yong
authors.initials: ZY
authors.lastname: Zeng
authors.forename: He-Zhong
authors.initials: HZ
authors.lastname: Cheng
mesh_terms: D002294:Carcinoma, Squamous Cell / Q000235:genetics* / Q000473:pathology; D045744:Cell Line, Tumor; D002465:Cell Movement / Q000235:genetics; D000071221:Enhancer of Zeste Homolog 2 Protein; D004938:Esophageal Neoplasms / Q000235:genetics* / Q000473:pathology; D000077277:Esophageal Squamous Cell Carcinoma; D005260:Female; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D035683:MicroRNAs / Q000235:genetics*; D009362:Neoplasm Metastasis / Q000235:genetics; D009367:Neoplasm Staging; D063151:Polycomb Repressive Complex 2 / Q000235:genetics*; D012323:RNA Processing, Post-Transcriptional
chemical_list: C534072:MIRN101 microRNA, human; C547397:MIRN214 microRNA, human; C546084:MIRN98 microRNA, human; D035683:MicroRNAs; C498409:EZH2 protein, human; D000071221:Enhancer of Zeste Homolog 2 Protein; D063151:Polycomb Repressive Complex 2