目的：通过慢病毒介导沉默表皮生长因子样结构域7基因 (epidermal growth factor-like domain 7, EGFL7 )在肺癌A549细胞的表达，探讨 EGFL7对A549细胞的增殖、凋亡、侵袭和血管生成的影响。 方法： 利用慢病毒介导靶向 EGFL7的shRNA 转染A549细胞，实验分三组： LV-RNAi组（转染LV-RNAi），LV-NC组（转染空病毒）和对照组（A549细胞）。Real-time PCR和Western blotting分别检测LV-RNAi感染对A549细胞 EGFL7 mRNA和蛋白水平表达的影响，MTT法和流式细胞术分别检测沉默〖STBX〗EGFL7〖STBZ〗对A549细胞增殖和凋亡的影响，Transwell侵袭实验和鸡胚绒毛尿囊膜（chick embryo chorioallantoic membrane，CAM）实验分别检测沉默 EGFL7 对A549细胞侵袭和血管生成能力的影响。 结果： 慢病毒稳定高效地转染A549细胞，LV-RNAi组细胞内 EGFL7 mRNA\[（0.18±0.03） vs （0.98±0.05）、（1.03±0.09），P<0.05\]和蛋白表达较LV-NC组和对照组显著降低。与LV-NC组及对照组相比，沉默EGFL7 对LV-RNAi组A549细胞的增殖活力\[感染120 h 时：（073±0.22） vs （0.79±0.08） vs （0.81±0.11），P>0.05\]与和凋亡率\[感染120 h 时：（1.92%±0.06） vs （2.11%±0.07） vs （1.85%±0.13）, P>0.05\]均无显著影响；同时，LV-RNAi组A549细胞侵袭入下室细胞数\[（61.7±14.5） vs （272.8±215）、（286.6±40.0）/mm2，P<0.05\]与血管生成指数\[（31.7±4.1） vs （96.3±4.4）、（103.3±6.5），P<0.05\]均显著减少。 结论： 沉默 EGFL 基因能够抑制A549细胞侵袭和血管生成能力，但不影响其增殖与凋亡。

Objective:To investigate the effect of epidermal growth factor-like domain 7 ( EGFL7 ) on the proliferation, apoptosis, invasion and angiogenesis of lung carcinoma A549 cells through silence EGFL7 by lentivirus infection. Methods: Lentivirus mediated small hairpin RNA target EGFL7 (LV-RNAi) were transfected into A549 cells. Three groups were designed in this study: a LV-RNAi group (A549 cells transfected with LV-RNAi), a LV-NC group (A549 cells transfected with the control GFP-lentivirus) and a control group (A549 cells). Real-time PCR and Western blotting were performed to detect the effect of LV-RNAi infection on the expression of EGFL7 mRNA and protein in A549 cells. MTT assay and flow cytometry were used to analyz the influence of silence EGFL7 on the growth and apoptosis of A549 cells, respectively. Transwell invasion assay and chick embryo chorioallantoic membrane (CAM) assay were used to detect the influence of silence  EGFL7 on the angiogenesis and invasion, respectively. Results: Lentivirus infected A549 cells stably and efficiently. Expression of  EGFL7 mRNA （\[0.18±0.03\] vs \[0.98±0.05\], \[1.03±0.09\]; P<0.05） and protein of the LV-RNAi group were significantly reduced compared with that of the LV-NC group and control group. Compared with the LV-NC group and control group, silencing EGFL7 showed no obvious influence on the proliferation capacity (120 h after infection: \[0.73±0.22\] vs \[0.79±0.08\] vs \[0.81±0.11\], P>0.05) and apoptosis rate (120 h after infection: \[1.92%±0.06\] vs \[2.11%±0.07\] vs \[1.85%±0.13\], P>0.05) of A549 cells in the LV-RNAi group; meanwhile, the invasion cell number (\[61.7±14.5\] vs \[272.8±21.5\], \[286.6±40.0\]/mm2; P<0.05) and the angiogenesis index (\[31.7±4.1\] vs \[96.3±4.4\], \[103.3±6.5\]; P<0.05) were significantly decreased in the LV-RNAi group. Conclusion: Silencing EGFL7gene may inhibit the invasion ability and the angiogenesis ability of A549 cells without affecting the proliferation and apoptosis.

国家自然科学基金面上项目资助（No. 30972718），江苏省自然科学基金资助项目（No. BK2012606），江苏省研究生创新工程资助项目（No. CXZZ12_0837），江苏省属高校自然科学研究面上项目资助（No. 13KJB320019）