中文摘要：

目的探讨缺氧诱导因子1α（HIF－1α）对人食管癌及胃癌细胞体外增殖、迁移及血管生成拟态的影响。方法将HIF－lα－shRNA重组质粒pGCsi－shHIF－1α稳定转染人食管鳞癌细胞Eca－109和胃腺癌细胞SGC－7901，采用Western blot方法检测常氧及缺氧情况下各组转染细胞HIF－1α的抑制效果，采川平板克隆形成实验和四甲基偶氮唑蓝（MTr）法检测转染细胞的增殖活性，采用Transwell小室检测转染细胞的迁移能力，采用三维培养方法观察Eca－109和SGC－7901细胞能否形成血管网状结构及转染细胞株的管腔形成能力。结果常氧及缺氧情况下，各转染组细胞HIF－lα蛋白表达最均为0，与未转染组（Eca－109组分别为0．74±0．05和1．11±0．06，SGC-7901组分别为0．60±0．05和0．96±0．07）比较，表达均被显著抑制（均P〈0．01）。与空载体组和未转染组相比，转染组细胞的增殖活性显著降低（均P〈0．05），体外迁移能力显著降低（均P〈0．01）。Eca－109细胞株各组中，常氧情况下，Eca－109组和Eca－109／shRNA组形成管状结构数目分别为（30．8±3．9）个和（3．7±2．8）个，差异有统计学意义（P〈0．01）；缺氧情况下，分别为（34．3±3．4）个和（3．9±2．7）个，差异有统计学意义（P〈0．01）。缺氧情况下，Eca－109组形成管状结构数目较常氧时明显增加（P〈0．05）。SGC-7901细胞株各组中，常氧情况下，SGC-7901组和SGC-7901／shRNA组形成管状结构数目分别为（26．2±3．4）个和（4．9±3．5）个，差异有统计学意义（P〈0．01）；缺氧情况下，分别为（30．1±4．1）个和（5．3±3．6）个，差异有统计学意义（P〈0．01）。缺氧情况下，SGC-7901组形成管状结构数目较常氧时明显增加（P〈0．05）。结论Eca－109细胞和SGC-7901细胞均能形成血管生成拟态管状结构。RNA下扰沉默HIF－1能有效抑制Eca－109细

英文摘要：

Objective To investigate the effect of hypoxia inducible factor-lα （HIF-lα） on the proliferation, migration and vasculogenic mimicry（VM） in human esophageal squamous cell carcinoma cell line Eca-109 and gastric adenocarcinoma cell line SGC-7901 in vitro. Methods The recombinant plasmid pGCsi-shHIF-lα was transfected into Eca-109 and SGC-7901 cells by Lipofectamme 2000. The inhibitory effect of HIF-lα was measured at protein level by Western blot under normoxia and hypoxia. The cell proliferation was detected by colony formation and MTY assays. The migration of transfected cells was assayed using Transwell chambers. Whether Eca-109 and SGC-7901 cells could form the capillary tube-like structures （TLSs） was observed by 3-dimensional culture, and the tube formation of transfected cells was detected by tube-like structure formation assay. Results The expression of HIF-lα protein in each group of transfected cells was significantly suppressed under normoxia and hypoxia （ Eca-109 ： 0.00, 0.74 ± 0.05 ; 0.00, 1.11 ± 0.06 ; SGC-7901 ： 0.00, 0.60 ± 0.05 ; 0.00, 0.96 ± 0.07, P 〈 0.01 ）. Colony formation and MTF assays showed that the cell proliferation of the pGCsi-shHIF-lα transfected ceils was slower than that of the control groups （104.7 ±9.6, 151.7±4.5; 88.3 ±5. 1, 128.3 ±6.7, P〈0.05）. Themigration of the recombinant plasmid-transfected cells was significantly suppressed compared with that of cells transfected with empty vector （55.5 ± 11.2, 121.9 ± 17.3 ; 64.7 ± 10.8, 132.3± 16.0, P 〈0.01 ）. Both the Eca-109 and SGC-7901 cells could form TLSs when cultured on matrigel, and the number of tubules was significantly increased under hypoxia （30.8 ± 3.9, 34.3 ± 3.4 ; 26.2± 3.4, 30.1 ±4.1, P 〈 0.05 ） , the tubule-forming ability of transfected groups was significantly inhibited under normoxia and hypoxia （ Eca- 109：3.7 ±2.8, 30.8 ±3.9; 3.9 ±2.7, 34.3 ±3.4; SGC-7901 ： 4.9 ±3.5, 26.2 ±3.4; 5.3 ±3.6, 30.1 ±4.1, P 〈0.01）. Conclusions Both the esophage