肝癌组织血管内皮生长因子表达水平的免疫组化研究

目的　旨在研究血管内皮生长因子 (VEGF)与肝癌微血管形成、生长和转移诸方面的关系。方法　对临床 3 6例肝癌术后癌组织 ,以免疫组织化学法研究VEGF在肿瘤组织的胞内分布及其表达 ;并以ELISA法测定癌灶、癌旁及远癌组织中的VEGF蛋白的表达水平。结果　癌组织中VEGF阳性表达率为 63 .9% ;无包膜或包膜不完整组VEGF阳性表达率与有包膜组存在显著差异 ;肝癌伴有远处转移组VEGF阳性表达水平显著高于无转移组 (P <0 .0 1) ,癌灶组织中VEGF的表达水平明显高于癌旁、远癌组织(P <0 .0 1)。结论资料提示VEGF在肝癌组织中高度表达 ,它在HCC的血管形成、肿瘤发展和转移过程中起重要作用 ,提示癌组织中VEGF过度表达是反映肿瘤侵袭生长及转移潜能的有效指标     

High serum levels of vascular endothelial growth factor in patients with human hepatocellular carcinoma

Vascular endothelial growth factor (VEGF) is intimately involved in neovascularization. In addition, it is know that in human hepatocellular carcinoma (HCC), angiogenesis is indispensable for tumor growth. In this study, we measured the serum VEGF levels of patients with HCC and studies the relationship between the serum VEGF level and maximum tumor diameter as well as that between the serum VEGF level and the serum α-fetoprotein (AFP) level. Mean serum VEGF level were 5.33 ± 0.77, 3.97 ± 0.68, 2.64 ± 0.78, and 2.57 ± 0.97 ng/ml for patients with HCC, chronic hepatitis (CH), or liver cirrhosis (LC) and normal controls (NC), respectively, with that of the HCC patients being significantly (P < 0.05) higher than that of the LC patient or NC. In addition, the serum VEGF level was significantly (r = 0.53, P < 0.05) correlated with the maximum tumor diameter in the HCC patients, and the sera of the patients with hypervascular HCC showed a significantly (P < 0.01) higher VEGF titer than the sera of the patients with isovascular or hypovascular HCC. However, there was no significant correlation between serum VEGF level and serum AFP level. These findings suggest that VEGF may play an important role, apart from that in AFP production, in the development of HCC.     

Expression of vascular endothelial growth factor-C in human hepatocellular carcinoma

Background/Aims: Vascular endothelial growth factor‐C (VEGF‐C) is thought to be an important factor in tumor angiogenesis/lymphangiogenesis, but its role in hepatocellular carcinoma (HCC) has not yet been fully investigated. Methods: We immunohistochemically examined VEGF‐C expression in surgically resected tissues of 90 HCC. Results: In the 78 HCC with a single histological grade, VEGF‐C expression was significantly stronger in poorly differentiated HCC than in well‐ (P = 0.003) or moderately differentiated HCC (P = 0.0002). A ‘nodule‐in‐nodule’ case presented VEGF‐A expression in the well‐differentiated component and VEGF‐C expression in the moderately–poorly differentiated component. According to nodular diameter, VEGF‐C expression was significantly higher in nodules of 3.0 cm or larger (P = 0.0263). Extrahepatic metastases seen in seven cases expressed VEGF‐C. In 20 of the 28 cases who were able to be followed up, the frequency of intrahepatic recurrence tended to be higher and extrahepatic metastasis was significantly higher in the cases who had VEGF‐C expression in the tumor casts of the intrahepatic portal/hepatic vein branches than other cases without the expression (P = 0.0139). Disease‐free survival time tended to be shorter in cases with VEGF‐C expression in tumor casts of the portal/hepatic vein than in those without VEGF‐C expression (P = 0.053; log–rank test). Conclusions: VEGF‐C expression is related to the progression of HCC, and VEGF‐C expression in tumor casts of the intrahepatic portal/hepatic vein is considered to be a factor indicating recurrence/metastasis sites.     

Clinical significance of vascular endothelial growth factor expression and neovascularization in colorectal carcinoma

AIM: To clarify the association of vascular endothelial growth factor (VEGF) and microvascular density (MVD)expression with the angiogenesis and prognosis of colorectal cancer.METHODS: A total of 97 cases of colorectal carcinomas were examined by immunohistochemical staining (SP method), using anti-VEGF and anti-factor CD34+ monoclonal antibodies. RESULTS: VEGF positive staining was obtained in 68 out of 97 cases (70.1%), and observed mainly in the cytoplasm of tumor cells, and also frequently in stromal cells. VEGF expression was more intense in poorly differentiated adenocarcinoma in comparison with others, but there was no significant correlation between VEGF expression and age,sex and stage. A significant correlation was found between the MVD and grades, and there was no significant relationship between the MVD and age, sex, and stage. The MVD in the VEGF positive group (68 cases) was higher than that in the negative group. Upon multivariate analysis, the significant variables were stage, tumor grade and MVD; VEGF expression was not an independent prognostic factor. CONCLUSION: The expression of VEGF has a significant correlation with MVD; MVD expression has prognostic value but VEGF has not in colon cancer.     

大肠癌血管内皮生长因子和新生血管的临床意义研究

目的　探讨血管内皮生长因子 (VEGF)和微血管密度 (MVD)在大肠癌组织中的表达 ,及其与肿瘤血管生成和预后的关系。方法　采用免疫组织化学方法 ,分别用 VEGF抗体和 CD34 因子抗体检测 97例大肠癌组织标本中 VEGF的表达水平和 MVD。结果　 97例大肠癌组织中 6 8例 VEGF阳性表达 ,主要表达于肿瘤细胞浆内 ,在低分化腺癌中的表达量最高 ;VEGF表达与性别、年龄和临床分期无相关性 ;VEGF阳性者和 VEGF阴性者的 MVD值比较有极显著性差异 (P<0 .0 1)。结论　大肠癌组织中 VEGF阳性表达不能作为判断患者预后的独立指标。 VEGF在大肠癌的肿瘤血管生成过程中发挥重要作用 ;MVD可以作为大肠癌患者独立的预后指标     

Clinical significance of vascular endothelial growth factor expression and neovascularization in colorectal carcinoma

AIM: To clarify the association of vascular endothelial growth factor (VEGF) and microvascular density (MVD) expression with the angiogenesis and prognosis of colorectal cancer.METHODS: A total of 97 cases of colorectal carcinomas were examined by immunohistochemical staining (SP method), using anti-VEGF and anti-factor CD34(+) monoclonal antibodies.RESULTS: VEGF positive staining was obtained in 68 out of 97 cases (70.1 %), and observed mainly in the cytoplasm of tumor cells, and also frequently in stromal cells. VEGF expression was more intense in poorly differentiated adenocarcinoma in comparison with others, but there was no significant correlation between VEGF expression and age, sex and stage. A significant correlation was found between the MVD and grades, and there was no significant relationship between the MVD and age, sex, and stage. The MVD in the VEGF positive group (68 cases) was higher than that in the negative group. Upon multivariate analysis, the significant variables were stage, tumor grade and MVD; VEGF expression was not an independent prognostic factor.CONCLUSION: The expression of VEGF has a significant correlation with MVD; MVD expression has prognostic value but VEGF has not in colon cancer.     

Expression of vascular endothelial growth factor in surgical specimens of hepatocellular carcinoma

Purpose: Vascular endothelial growth factor (VEGF) has been reported to play an important role in angiogenesis in hepatocellular carcinoma (HCC). However, there is great variation in reports on the distribution of VEGF expression, especially in non-carcinoma liver cells. Furthermore, some reports have mentioned that endothelial cells were positive for VEGF antibody but have not evaluated its significance. In this study, we focused our attention to these problems and try to solve them. We also analyzed the factors influencing VEGF expression and evaluated the prognostic potential of VEGF protein in HCC. Methods: We examined the VEGF expression in specimens surgically removed from 46 HCC patients and 3 patients with liver cancer metastatic from the colon, and in 4 specimens of liver tissue with benign disease, by immunohistochemical methods. Results/conclusions: VEGF was expressed in HCC cells and hepatocytes and on vascular endothelial cells. Our finding that about seven times more endothelial cells were positive for VEGF antibody in carcinoma areas than in non-carcinoma areas (P < 0.001) suggests that VEGF is a very important angiogenesis factor for HCC growth. VEGF expression in HCC cells and non-carcinoma liver cells and on endothelial cells did not closely correlate with the disease recurrence rate (P > 0.05), suggesting that VEGF expression may not be useful as an individual factor for estimating the prognosis of HCC. A statistical analysis of the relationships between VEGF expression and clinicopathological variables revealed the following: preoperative transcatheter arterial embolization enhanced VEGF expression in both HCC cells and non-carcinoma liver cells. The histological grade of HCC and the level of alanine aminotransferase was related to VEGF expression in non-carcinoma liver cells and on endothelial cells in HCC areas. Tumor size and the histological status of the accompanying chronic hepatitis also influenced the VEGF expression on endothelial cells. Our findings concerning not only HCC but also the surrounding liver and endothelial cells may provide useful information for further research on the role of VEGF expression in HCC patients. Received: 29 July 1999 / Accepted: 11 October 1999     

Clinicopathological features of hepatocellular carcinoma evaluated by vascular endothelial growth factor expression

AIM: To evaluate the significance of the expression of vascular endothelial growth factor (VEGF), its correlation with clinicopathological variables were studied in the tissue of hepatocellular carcinoma (HCC) and surrounding liver. METHODS: In 56 samples (tumor and non-tumor liver tissue) collected from 28 patients, VEGF expression was examined by immunohistochemistry and western blot analysis. RESULTS: The value of VEGF expression by western blotting was correlated with immunohistochemical staining grade. In tumor tissue, the value of VEGF expression correlated with tumor size (P = 0.034), á-fetoprotein (P = 0.036) and protein induced by vitamin K absence-II by simple regression, and histological grade (P = 0.0132) by the unpaired t-test. The level of VEGF expression in non-tumor liver was found to correlate with the value of serum albumin (P = 0.008), cholinesterase (P = 0.012) and prothrombin activity (P = 0.046). The frequency of simple nodular type in gross appearance decreased in cases with high tumor/non-tumor (T/N) ratio (P = 0.022), and the degree of portal vein invasion progressed with an increase in the T/N ratio (P = 0.008). The T/N ratio was significantly higher in early recurrence cases (P = 0.0081). CONCLUSION: This study on the expression of VEGF might be useful to estimate the liver condition and the clinicopathological features of HCC.     

Synergistic effect of basic fibroblast growth factor and vascular endothelial growth factor in murine hepatocellular carcinoma

The growth of any solid tumor depends on angiogenesis. Among the known angiogenic factors, basic fibroblast growth factor (bFGF) and vascular endothelial growth factor (VEGF), are potent and representative factors involved in tumor development. It has been reported that bFGF and VEGF showed a synergistic effect in both in vitro and in vivo angiogenesis. However, the interaction of these factors on tumor development and angiogenesis, including hepatocellular carcinoma (HCC), has not yet been elucidated. In this study, we examined the combined effect of bFGF and VEGF overexpression by means of a combination of a retroviral tetracycline (tet)-regulated (Retro-Tet) gene expression system, which can manipulate the gene expression in vivo by providing tet in the drinking water, and a conventional plasmid gene expression system. In an allograft study, bFGF and VEGF overexpression synergistically increased tumor growth and angiogenesis in the murine HCC cells. This synergistic effect also was found in established tumors. VEGF messenger RNA (mRNA) expression in the tumor was increased 3.1-fold by bFGF-overexpression, and the bFGF-induced tumor development was significantly attenuated by treatment with KDR/Flk-1 neutralizing monoclonal antibody. In conclusion, these results suggest that bFGF synergistically augments VEGF-mediated HCC development and angiogenesis at least partly by induction of VEGF through KDR/Flk-1.     

Prognostic implication of serum vascular endothelial growth factor in advanced hepatocellular carcinoma staging

Background. Staging systems have considerable impact on hepatocellular carcinoma (HCC) treatment approaches and outcomes. There is an unmet need to improve their stratification ability. We have evaluated four commonly used staging systems and assessed whether angiogenic biomarker vascular endothelial growth factor (VEGF) could improve their prognostic stratification.Material and methods. Four staging systems; Okuda, Cancer of the Liver Italian Program (CLIP), Barcelona Clinic Liver Cancer (BCLC), and Child-Pugh were evaluated in 78 HCC patients; their stratification abilities were detected by Kaplan-Meier curves and log-rank test; their accuracies of predicting survival were compared with the concordance index. Serum VEGF levels were measured using ELISA method. Recursive partitioning was used to determine the optimal VEGF cutoff. The prognostic significance of VEGF cutoff and other parameters were analyzed using univariate and multivariate models.Results. None of the staging systems demonstrated better discriminatory ability in predicting survival. The four staging systems did not reveal significant differences in probability of survival across their intermediate-advanced stages. Optimal cutoff identified for VEGF was 445 pg/mL. In advanced HCC, VEGF level (p = 0.004) and in early HCC, bilirubin level (p = 0.009) were identified as the independent prognostic factors. Survival comparison with high and low VEGF levels was significant for advanced HCC, while insignificant for early disease.Conclusion. Staging systems with conventional parameters did not provide good prognostic stratification for survival in advanced HCC population. Serum VEGF level was an independent predictor of survival in advanced HCC, and provided more survival homogeneity within the advanced stages of conventional staging systems.