人EGFR显性负性突变体抑制胃癌细胞促血管形成能力

摘要

Objective To explore the effect of dominant negative epidermal growth factor receptor (DNEGFR) on the pro-angiogenic ability of human gastric cancer cells, to elucidate molecular mechanisms, and to explore the effect on subcutaneous xenotransplanted tumor in nude mice. Methods Two human gastric cancer cell lines were selected for the study. Cells were divided into 6 groups: untreated SGC-7901 and NCI-N87 cell groups (US, UN), SGC-7901 and NCI-N87 cell groups stably transfected with pEGFP-N1 (ES, EN), SGC-7901 and NCI-N87 cell groups stably transfected with pEGFPN1-DNEGFR (DS, DS). The pro-angiogenic ability in vitro was tested by human umbilical vein endothelial cell (HU-VEC) tube formation assay, vascular endothelial growth factor (VEGF) in culture medium was tested by ELISA. The subcutaneous xenotransplanted tumor model of human gastric cancer in nude mice was established, the pro-angiogenic ability in vivo was assessed by microvessel density (MVD), and the effect on tumor growth was detected by tumor volume measurement. Results Transfection with pEGFPN1-DNEG-FR of human gastric cancer cells reduced HUVEC tube formation, VEGF in culture medium, MVD of specimen and tumor volume as well. Conclusion DNEGFR may inhibit the pro-angiogenic ability in vitro and in nude mice by down-regulating VEGF secretion in human gastric cancer cells, leading to the growth inhibition of subcutaneous xenotransplanted tumor in the end.%目的 探讨人表皮生长因子显性负性突变体(dominant negative epidermal growth factor receptor,DNEGFR))对胃癌细胞促血管形成能力的影响及其分子机制,并检测其对裸鼠皮下移植瘤生长的影响.方法 选用2株人胃癌细胞,分为如下6组:SGC-7901及NCI-N87细胞未转染组(US组,UN组),SGC-7901及NCI-N87细胞pEGFP-N1质粒转染组(ES组,EN组),SGC-7901及NCI-N87细胞pEGFPN1-DNEGFR质粒转染组(DS组,DN组).采用人脐静脉内皮细胞(human umbilical vein endothelial cell,HUVEC)管腔结构形成实验检测体外促血管形成能力,采用酶联免疫吸附测定法 (enzyme-linked immunosorbent assay,ELISA)测定细胞培养液中血管内皮生长因子(vascular endothelial growth factor,VEGF)的水平,建立人胃癌细胞裸鼠移植瘤模型,标本微血管密度(microvessel density,MVD)检测体内促血管形成能力,标本体积检测其对裸鼠皮下移植瘤生长的影响.结果 转染pEGFPN1-DNEGFR质粒的人胃癌细胞株出现HUVEC管腔结构形成抑制,培养液中VEGF水平降低,MVD计数降低,裸鼠皮下移植瘤体积变小.结论 DNEGFR可能通过下调VEGF分泌抑制胃癌细胞体外及裸鼠体内促血管形成能力,最终抑制裸鼠皮下移植瘤生长.