目的：探讨食管癌（esophageal carcinoma，EC）细胞中miR-92b 对组蛋白甲基转移酶zeste 同源物增强子2(enhancer of zeste homolog 2,EZH2)基因表达的调控作用，以及对EC细胞增殖和侵袭能力的影响。方法：选取河北医科大学第四医院科研中心保存的2016 年1 月至2017 年1 月15 例EC患者手术癌组织标本，通过生物信息学软件预测分析对EZH2 可能调控的miRNAs，将预测的miRNAs mimic 分别转染人EC细胞Eca109 后，采用实时荧光定量PCR、Western blotting 和双荧光素酶报告基因实验验证miRNAs对EZH2 基因的靶向调控作用。同时将EZH2 过表达质粒共转染至Eca109，然后采用CCK-8 法、流式细胞术和Transwell 细胞侵袭及迁移实验分别检测miRNAs 和EZH2 表达变化对EC 细胞增殖、凋亡、侵袭和迁移的影响。结果：转染miR-92b 的Eca109 细胞中EZH2 mRNA与mimic-NC相比明显降低(P<0.01)，转染miR-92b 的Eca109 细胞中EZH2 蛋白表达水平明显低于转染mimic-NC组(0.525±0.052 vs 0.689±0.026，P<0.01）。生物信息学软件分析显示，miR-92b、let-7a 及miR-25 可与EZH2 基因3’端非翻译区的结合位点相结合，但仅有miR-92b 可以调控EZH2 基因的表达，且miR-92b 表达与EZH2 mRNA表达成负相关(P<0.01)。miR-92b mimic 转染后EZH2 mRNA、蛋白及荧光素酶报告基因活性均明显下调（均P<0.01），对Eca109 细胞凋亡无明显影响(P>0.05)；miR-92b mimic 转染能抑制ECa109 细胞的增殖和侵袭及迁移能力(P<0.01)。而EC细胞转染EZH2 过表达质粒后，miR-92b mimic 对ECa109 细胞增殖和侵袭及迁移能力的抑制作用明显减弱(P<0.01)。结论：miR-92b 可抑制ECa109细胞的增殖和侵袭及迁移能力，其作用机制可能与靶向调控抑癌基因EZH2 的表达有关。

Objective: To investigate the regulating effects of miR-92b on the expression of EZH2 (enhancer of zeste homolog 2) gene and the proliferation and invasion abilities of esophageal cancer (EC) cells. Methods: Fifteen cases of esophageal cancer tissues that preserved in the research center of the Fourth Hospital Affiliated to Heibei Medical University from January 2016 to January 2017 were selected for this study. The bioinformatics tool was used to predict the possible miRNAs that might target EZH2. The mimics of predicted miRNAs were transfected into human esophageal carcinoma cell lines Eca109, respectively. Then the regulation effect of miRNAs on EZH2 gene expression was validated by real-time PCR, Western blotting and dual luciferase reporter experiment. In the meanwhile,EZH2 over-expression plasmids were co-transfected into esophageal carcinoma Eca109 cells, and the effects of miRNAs and EZH2 expression changes on the proliferation, apoptosis , invasion and migration of esophageal carcinoma cells were detected by CCK-8 method,Flow Cytometry, Transwell Invasion and migration assay, respectively. Results: Bioinformatics analysis showed that miR-92b, let-7a and miR-25 could combine with potential binding sites at 3’-terminal non-translation region of EZH2 gene. Real-time PCR results showed that only miR-92b was able to regulate the expression of EZH2, and miR-92b was negatively correlated to EZH2 in esophageal cancer (P<0.01). Compared with mimic-NC, the expression of EZH2 mRNA, protein and luciferase activity in Eca109 cells after miR-92b mimic transfection was significantly down-regulated (both P<0.01). However, miR-92b mimic transfection had no effect on the apoptosis of Eca109 cells. Moreover, the proliferation, invasion and migration of Eca109 cells were significantly inhibited after transfection with miR-92b-mimic (P<0.01). In addition, after co-transfection with EZH2 over-expression plasmids, the effects of miR-92b-mimic on the proliferation, invasion and migration of Eca109 cells were significantly weakened (P<0.01). Conclusion: miR-92b can inhibit the proliferation, invasion and migration of esophageal carcinoma cells, and its mechanism may be related to its target regulation ofEZH2.

河北省杰出青年基金资助项目（No.2016206410）