血管内皮细胞钙黏蛋白和血管内皮生长因子在肝癌中的表达及其对血管内皮细胞的影响

The expression of vascular endothelial cadherin and vascular endothelial growth factor in hepatocel- lular carcinoma and its impact on vascular endothelial cells

目的观察血管内皮细胞钙黏蛋白（VE—cadherin）和血管内皮生长因子（VEGF）在人肝癌组织中的表达相关性，探索肿瘤细胞对内皮细胞功能的影响。方法分别取22例肝癌组织和癌旁组织标本，应用免疫组织化学方法检测VE—cadherin和VEGF在肝癌组织和癌旁组织中的表达；酶联免疫吸附试验（ELISA）检测HepG2细胞培养上清中VEGF的浓度；收集HepG2细胞培养上清刺激人脐静脉内皮细胞（HUVEC），采用Westernblot检测丝裂原活化蛋白激酶（MAPK）和VE—cadherinY658位点的活化，Trans well法检测内皮细胞迁移能力。结果HepG2和人正常肝细胞系L02细胞培养上清中分泌VEGF浓度平均值分别为558．43ng／L和42．73ng／L，提示人肝癌细胞株HepG2可分泌丰富的VEGF；与癌旁组织比较，肝癌组织中VE-cadherin和VEGF均有显著高表达，其强阳性（卅）表达率分别为63％（14／22）和73％（16／22），提示与疾病进展有一定相关性；用HepG2细胞培养上清刺激HUVEC，可检测到MAPK的活化和VE—cadherinY658位点的磷酸化，以及内皮细胞迁移速率的增强。结论肝癌组织可通过VEGF等生长因子的分泌引起内皮细胞活化、迁移增强、新生血管形成增多，从而进一步促进肿瘤的发展。

Objective To observe the expression of the vascular endothelial cadherin （ VE - eadherin） and vascular endothelial growth factor （VEGF） in human hepatoma tissues and to explore the impact of tumor cells on endothelial cell function. Methods The 22 samples of hepatocellular carcino- ma （HCC） and adjacent tissues were taken to confirm the VE -cadherin and VEGF expressions by immuno- histoehemistry. The HepG2 cell culture supernatant expression of VEGF was detected by enzyme linked im- munosorbent assay （ELISA） ; HepG2 cell culture supernatants were collected and used to stimulate human umbilical vein endothelial cell （HUVEC） endothelial cells. The activation of mitogen- activated protein ki- nase （MAPK） and VE -cadherin Y658 site was detected by Western blotting. Transwell assay was used to detect the migrational ability of endothelial cell. Results The expression of VEGF were 558.43 ng/L and 42. 73 ng/L in the culture supernatant of HepG2 and L02 cells, and The expression of VEGF was significant- ly higher. Compared with adjacent tissue, the expressions of VE - cadherin and VEGF in liver cancer was 63% （14/22） and 73% （16/22）, and with a certain correlation between disease progression. Using HepG2 cell culture supernatant stimulated HUVEC endothelial cells, we found the MAPK and the phosphorylation of VE -cadherin on Y658 were activation, and the rate of migration in endothelial cells was also enhanced. Conclusion The liver cancer can, increase the rate of migration ability and neovascularization of endothelial cells by secreting growth factors such as VEGF to further promote tumor development.