肝癌组织、缺氧SMMC-7721细胞中HPA的表达变化及机制探讨

目的观察肝癌组织及缺氧培养的肝癌SMMC-7721细胞中乙酰肝素酶（HPA）和缺氧诱导因子-1α（HIF-1α）的表达变化,并探讨其机制。方法免疫组化法检测50例肝癌组织、28例肝癌癌旁组织、14例正常肝组织中的HPA、HIF-1α蛋白。分别采用RT-PCR和Western blot法检测常氧和缺氧培养的人肝癌SMMC-7721细胞中HPA mRNA及其蛋白。结果 HPA、HIF-1α蛋白在肝癌组织中的阳性表达率显著高于癌旁和正常肝组织（P〈0.05）;肝癌组织中HPA、HIF-1α蛋白的表达呈正相关（r=0.295,P〈0.05）。缺氧培养20 h后,SMMC-7721细胞HPA mRNA表达量（6.234±0.457）显著高于常氧培养细胞的表达量（2.910±0.137）,两者相比,P〈0.05;其HPA蛋白表达量（65 kD为1.437±0.067,50 kD为1.706±0.066）也显著高于常氧培养细胞的表达量（65 kD为1.192±0.060,50 kD为1.580±0.265）,两者相比,P〈0.05。结论肝癌组织中HPA蛋白阳性表达率升高,缺氧肝癌SMMC-7721细胞中HPAmRNA及蛋白表达量均升高,可能与缺氧导致的HIF-1α表达上调有关。

Expression change and mechanism of HPA in hepatocellular carcinoma tissue and liver cancer cell line SMMC-7721 cultured in hypoxic condition

Objective To observe the expression change of heparanase（HPA） and HIF-1α protein in hepatocellular carcinoma tissue and human liver cancer cell line SMMC-7721 cultured in hypoxic condition,and to document the mechanism.Methods Immunohistochemistry was used to detect the HPA and HIF-1α protein in 50 cases of hepatocellular carcinoma tissue,28 cases of tumor-surrounding tissue and 14 cases of normal liver tissue.SMMC-7721 cultured in normoxic and hypoxic condition,the HPA mRNA and protein were evaluated by RT-PCR and Western blot respectively.Results Both HPA and HIF-1α protein expression were higher in hepatocellular carcinoma tissue than that in tumor-surrounding tissue and in normal liver tissue（P〈0.05）.There was a positive relationship between the expression of HPA and HIF-1α protein（r = 0.295,P〈0.05）.In SMMC-7721 cell cultured in hypoxic group,the HPA mRNA was 6.234 ± 0.457（65 kD protein was 1.437 ± 0.067 and 50 kD was 1.706 ± 0.066）,but in normoxic group,it were 2.910 ± 0.137（65 kD was 1.192 ± 0.060 and 50 kD was 1.580 ± 0.265）,HPA mRNA and protein expression level were increased significantly compared with those in normoxic group（P〈0.05）.Conclusion HPA mRNA and protein expression level increased in hepatocellular carcinoma tissue and SMMC-7721 cultured in hypoxia environmentmay be related with the up-regulation of HIF-1α expression which mediated by hypoxia.