胃癌血管靶向肽GX2 对胃癌血管内皮细胞靶向性的鉴定

目的:证明胃癌血管靶向肽GX2能够与胃癌血管内皮细胞特异性结合,在体内对胃癌血管具有靶向性。方法:体外实验,合成GX2与FITC的复合物FITC-GX2,分离原代人脐静脉内皮细胞HUVEC,将HUVEC与人胃癌细胞系SGC7901共培养,建立共培养血管内皮细胞模型来模拟胃癌血管,利用免疫荧光的方法观察GX2与共培养内皮细胞Co-HUVEC的结合情况;体内实验,构建99mTc标记的GX2分子示踪探针,SPECT显像观察GX2的胃癌血管靶向性。结果:免疫荧光结果显示GX2能与Co-HUVEC特异性结合,而与人胃癌细胞SGC7901不结合;SPECT显像结果证明了GX2在荷瘤裸鼠体内能够浓集到肿瘤部位,具有良好的靶向性。结论:GX2能与胃癌血管内皮细胞特异性结合,且具有在体靶向到胃癌血管的能力;GX2具有胃癌诊断的潜在价值,并能应用于胃癌血管抑制治疗。

Identification of Targeting Ability of GX2 Homing to Gastric CancerVasculature

Objective: To identify targeting ability of GX2 homing to gastric cancer vasculature in vivo and in vitro.Methods: Hu-man umbilical vein endothelial cells(HUVEC) were isolated and cultured,and the tumor endothelial cell coculture model(Co-HUVEC) was prepared using HUVEC and the human gastric cancer cell line SGC7901 in Transwell plates.A FITC-GX2 complex were synthe-sized and used in immunofluorescence staining in vitro.Samples were examined using a fluorescence microscope and binding specificity to Co-HUVEC was evaluated.Besides,GX2 was labeled with the radioactive isotope 99mTc,and targeting efficacy was observed using SPECT imaging in the nude mice model bearing SGC7901 tumor xenografts.Results: Immunofluorescence staining demonstrated that GX2 bound specifically to Co-HUVEC but not to SGC7901 cells.SPECT imaging showed that GX2 targeted the tumor tissue.Conclusions: GX2 can bind specifically to Co-HUVEC and home to gastric cancer vasculature.GX2 can also be applied to diagnosis and therapy for tumor angiogenesis.