Tissue factor expression correlates with tumor angiogenesis and invasiveness in human hepatocellular carcinoma.

PURPOSE: Recent studies have shown that tissue factor (TF) may be involved in tumor angiogenesis and metastasis. The role of TF in hepatocellular carcinoma (HCC) was unknown. This study evaluated whether TF expression correlates with microvessel density (MVD), vascular endothelial growth factor (VEGF) expression, tumor invasiveness, and prognosis in human HCC. EXPERIMENTAL DESIGN: Tissue samples were obtained from 58 specimens of resected HCC. Immunohistochemical expression of TF was examined, and tumor MVD was evaluated using CD34 as the endothelial marker. TF and VEGF protein levels in the tumor cytosol were quantified by ELISA. Clinicopathologic and follow-up data of patients were prospectively collected. RESULTS: The immunohistochemical expression of TF in the tumors correlated significantly with tumor MVD (P = 0.002). The median cytosolic TF protein level in the tumors was 720 pg/mg total protein (range, 67-2406 pg/mg total protein). A significant positive correlation was found between TF and VEGF levels in the tumor cytosol (r = 0.475, P < 0.001). High tumor cytosolic TF level was associated with venous invasion (P = 0.004), microsatellite nodules (P = 0.024), unencapsulated tumor (P = 0.007), and advanced tumor stage (P = 0.010). A higher than median tumor cytosolic TF level was an independent predictor of poor survival (risk ratio, 1.836; 95% confidence interval 1.130-5.312, P = 0.023). CONCLUSIONS: This study shows that TF is related to tumor angiogenesis and invasiveness in HCC. Evaluation of tumor TF expression may be useful as a prognostic indicator in patients with HCC.     

Overexpression of Caveolin-1 in Hepatocellular Carcinoma with Metastasis and Worse Prognosis: Correlation with Vascular Endothelial Growth Factor, Microvessel Density and Unpaired Artery

Caveolin-1 is the major structural protein in caveolae, implicated in oncogenesis and angiogenesis. The connections between caveolin-1 and progression and angiogenesis of hepatocellular carcinoma (HCC) is still not clear. Thus we investigated the relationship of caveolin-1 expression, vascular endothelial growth factor (VEGF) expression, microvessel density (MVD), and unpaired artery (UA) with the clinicopathologic features of patients with HCC. Formalin-fixed, paraffin-embedded tissue sections of HCC from 75 patients who had undergone an initial hepatectomy were stained immunohistochemically with specific antibodies against caveolin-1, VEGF, CD34 and α-SMA. The levels of caveolin-1, VEGF, MVD and UA were correlated with the clinicopathologic variables, and tissue sections were also analyzed by dual-label immunofluorescence. We found that increased expression of caveolin-1 was associated with metastasis and with a worse prognosis of HCC. Caveolin-1 expression correlates positively with VEGF, MVD and UA. These results suggest that caveolin-1 may play an important role in the progression of HCC and angiogenesis.     

Expression of vascular endothelial growth factor in renal cell carcinoma and the relation to angiogenesis and p53 protein expression

BACKGROUND AND OBJECTIVES: Vascular endothelial growth factor (VEGF) seems to play an important role in tumor angiogenesis. The tumor-suppressor gene p53 has been thought to regulate VEGF expression. We investigated the effect of VEGF expression on renal cell carcinoma (RCC) and the correlation between the expression of VEGF and tumor angiogenesis and p53 protein expression. METHODS: Sixty-two RCCs were examined by immunohistochemical studies with anti-VEGF, anti-p53, and anti-CD34 antibodies. RESULTS: Forty tumors (80.6%) were classified as VEGF positive, and 28 tumors (45.2%) were positive for p53 protein. The microvessel density was 75.3 +/- 33.5. A significant correlation was found between VEGF expression and both the nuclear grade (P < 0.05) and the TNM stage (P < 0.05). The tumors with VEGF expression had a significantly higher microvessel density than those without VEGF expression (P < 0.01). There was no statistically significant correlation between p53 protein and VEGF expression. No statistically significant differences in survival were found to be associated with microvessel density, VEGF expression or p53 protein expression. By using multivariate survival analyses, nuclear grade (P < 0.05) and TNM stage (P < 0.05) were the only independent prognostic factors. CONCLUSIONS: Our data do not show a direct regulation of VEGF expression by p53. We suggest that VEGF expression plays a role in the promotion of angiogenesis in RCC.     

人肝癌组织中iNOS、VEGF的表达及微血管密度的病理意义

背景与目的:诱导型一氧化氮合酶(inducible nitric oxide synthase,iNOS)和血管内皮生长因子(vascular endothelial growth factor,VEGF)被认为是诱导和调节肿瘤血管生成,进而影响肿瘤病理进展和预后的重要相关因子。本研究检测人肝细胞癌(hepatocellular carcinoma,HCC)及相应癌旁组织中iNOS、VEGF的表达,探讨其与血管生成的关系,为临床诊治HCC及判断其预后提供理论依据。方法:应用组织芯片技术,采用原位杂交和免疫组化法分析147例HCC组织及癌旁组织中iNOS、VEGF的表达,并用CD34标记免疫组化法检测微血管密度(microvessel density,MVD)。结果:iNOS、VEGF在癌旁组织中的阳性率分别为33.33%和40.82%,而在癌组织中的阳性率分别为86.39%和78.91%,癌组织与癌旁组织比较差异有显著性(P<0.01)。癌组织的MVD值为56.5±12.8,癌旁组织的MVD值为8.4±3.6,两者差异有显著性(P<0.01)。iNOS的表达与肿瘤大小、乙型肝炎表面抗原(HBsAg)相关(P<0.05),而与转移和肿瘤分化程度无关(P>0.05)。VEGF的表达及MVD值与肿瘤大小、转移相关(P<0.05),而与HBsAg和肿瘤分化程度无关(P>0.05)。在癌组织中MVD与VEGF、iNOS的表达呈正相关,VEGF和iNOS之间亦存在正相关关系(P<0.01)。结论:HCC中iNOS及VEGF的表达与肿瘤血管生成有关。癌组     

Rac1 VEGF在肝细胞癌中的表达和肿瘤血管形成关系

  目的  探讨Rac1、VEGF蛋白在肝细胞癌组织的表达及其与肿瘤血管形成的关系。  方法  应用免疫组织化学法检测Rac1、VEGF在43例肝细胞癌组织、43例癌旁肝组织及21例正常肝组织的表达, 采用图像分析软件测定Rac1蛋白、VEGF蛋白的平均光密度, 根据CD34染色的血管内皮细胞计数肿瘤MVD。  结果  Rac1蛋白在癌组织、癌旁肝组织及正常肝组织均有表达, 位于胞浆, 癌组织表达高于癌旁肝组织(P < 0.01)、正常肝组织(P < 0.01);VEGF蛋白在癌组织、癌旁肝组织及正常肝组织均有表达, 位于胞浆, 癌组织高于癌旁肝组织(P < 0.01)、正常肝组织(P < 0.01);Rac1、VEGF与MVD之间均呈正相关(r=0.490, P=0.001;r=0.355, P=0.019), Rac1与VEGF之间呈正相关(r=0.583, P < 0.001)。  结论  Rac1可能通过上调VEGF的表达促进肿瘤血管生成, 参与HCC的侵袭、转移机制。      

姜黄素对化学诱导大鼠肝癌缺氧模型血管生成的影响

目的:探讨姜黄素对二乙基亚硝胺( diethylnitrosamine, DEN)诱发大鼠肝细胞癌（hepatocellular carcinoma, HCC）缺氧后血管形成的影响。方法: 采用DEN诱发大鼠HCC,结扎肝动脉并构建大鼠HCC缺氧模型。将HCC模型大鼠按照数字表法随机分为单纯碘化油栓塞组（A组）、碘化油联合姜黄素栓塞组（B组）、碘化油联合肝周包膜组（C组）、碘化油联合姜黄素及肝周包膜组（D组）,每组10 只。比较各组大鼠相应治疗后HCC细胞及组织VEGF、微血管密度（microvessel density,MVD）及大鼠中位生存时间（median survival time,MST）。结果：B组与D组的VEGF蛋白表达及MVD均比A组显著降低（P<0.01）,而C组上述指标则与A组无显著变化（P>0.05）。B、C、D组比A组大鼠MST均显著延长（P<0.05）,D组大鼠的MST高于B、C组（P<0.05）。结论：姜黄素可抑制HCC缺氧大鼠肿瘤血管的生成,可降低VEGF表达及MVD,起到延长大鼠生存期的作用。     

Expression of hypoxia-inducible factor-1alpha is associated with tumor vascularization in human colorectal carcinoma

HIF-1 is reported to transactivate expression of VEGF, which is an important angiogenic factor. To determine whether HIF-1alpha plays a role in angiogenesis through its regulation of VEGF, we examined expression of HIF-1alpha and its relation to clinicopathologic features, VEGF expression and prognosis of patients with colorectal carcinoma. Expression of HIF-1alpha and VEGF was examined in 4 colorectal carcinoma cell lines (COLO320DM, COLO201, DLD-1, WiDr) and 149 colorectal carcinoma tissues (10 fresh specimens, 139 archival, paraffin-embedded specimens). HIF-1alpha protein levels were increased by hypoxia in 3 of 4 colorectal carcinoma cell lines (COLO201, DLD-1, WiDr), and VEGF mRNA levels were also increased by hypoxia in the same cell lines. In 8 of 10 patients with colorectal cancer, expression of HIF-1alpha and VEGF was increased in tumor tissues compared to corresponding normal mucosa. Of 139 archival specimens of colorectal carcinoma, 81 (58.3%) expressed HIF-1alpha protein at a high level. HIF-1alpha expression was correlated with tumor invasion, tumor stage, lymphatic invasion, venous invasion and liver metastasis. Moreover, HIF-1alpha expression was correlated significantly with VEGF expression and microvessel density. Although there was a tendency for poorer prognosis in patients with high HIF-1alpha-expressing tumors, this correlation was not statistically significant. These findings suggest that HIF-1alpha may play a role in angiogenesis and tumor progression via regulation of VEGF in human colorectal carcinoma.     

Angiogenesis in gastric cancer: importance of the thymidine phosphorylase expression of cancer cells as an angiogenic factor

Thymidine phosphorylase (TP) has been reported to stimulate angiogenesis in a variety of human malignancies. We investigated TP expression and its association with angiogenesis in 73 cases of resected gastric cancer. In addition, we compared the expression of the other angiogenesis related factors (VEGF, eNOS and p53) with that of TP with respect to angiogenesis. TP expression was not detected in most of the non-tumoral glandular epithelial cells except for 5 cases. TP expression of the cancer cells and the stroma was assessed separately. The stromal TP expression was not associated with the TP expression of the cancer cells. The mean percent of TP reactive cancer cells was 18.36+/-2.61 (median, 10.00; range, 0-90) and cases showing a percentage higher than the mean were considered as bearing high reactivity. The mean microvessel score assessed was 90.44+/-3.69 (median, 86; range, 31-174). The TP expression of cancer cells was strongly associated with microvessel density (p=0.030), but the stromal TP expression was not. The microvessel density of the tumor showed strong correlation with VEGF expression (p<0.001), but a marginally significant association with eNOS (p=0.055). On the contrary, there was no association with p53 expression and microvessel density of the tumor. No significant correlation was detected between lymph node metastasis and tumoral or stromal TP expression or VEGF/TP coexpression. In gastric cancer, TP expression of the cancer cells, not stromal cells may play an important role in tumor growth by microvessel formation.     

VEGF及其受体KDR在宫颈癌的联合表达与局部肿瘤血管生成的关系

目的:探讨血管内皮生长因子及其受体KDR在早期宫颈癌的表达及其对宫颈癌肿瘤血管生成的作用。方法:采用免疫组织化学SP法检测18例宫颈上皮内瘤样病变(cervicalintraepithelialneoplasm,CIN)、75例早期宫颈癌(invasivecarcinomaofcervix,ICC)和15例正常宫颈上皮(normalcervicalepithelium,NCE)中VEGF和KDR的表达情况,并检测其中微血管密度(CD34标记)。结果:在ICC中,VEGF和KDR主要表达于癌细胞膜和(或)细胞浆;而CD34主要表达于癌巢间质血管内皮细胞。从NCE到CIN再到ICC,VEGF与KDR的阳性表达率以及MVD均显著升高(P<0.01)。在ICC中,VEGF、KDR阳性表达者其MVD分别显著高于VEGF、KDR阴性表达者(P<0.05)。VEGF在ICC的表达与KDR显著正相关(r=0.56,P<0.01),并且两者均与MVD显著正相关(前者r=0.60,P<0.01;后者r=0.33,P<0.01)。VEGF与KDR均阳性表达者,其微血管密度显著高于两者均阴性表达者(P<0.01)。结论:VEGF及其受体KDR表达在宫颈癌肿瘤血管生成中起上调作用,两者均过度表达,肿瘤血管生成显著增加。检测VEGF及其受体KDR的联合表达对进一步了解宫颈癌血管生成情况以及寻找抗肿瘤血管生成治疗新靶点有一定价值。     

Correlation of four vascular specific growth factors with carcinogenesis and portal vein tumor thrombus formation in human hepatocellular carcinoma

The aim of the present study was to detect the correlation between the expression of vascular endothelial growth factor (VEGF), angiopoietin 2 (Ang2), ephrinB2 and endocrine gland-derived vascular endothelial growth factor (EG-VEGF) and carcinogenesis or portal vein tumor thrombus (PVTT) formation in human hepatocellular carcinoma (HCC). The expression of VEGF, Ang2, ephrinB2 and EG-VEGF was detected by RT-PCR in 54 cases HCC without PVTT (group A), 9 cases HCC with PVTT (group B), 10 normal liver tissues (group D) and 10 cirrhosis tissues (group C). The samples were also stained with CD34 by immunohistochemistry. Quantitation of microvessel density (MVD) and semi-quantitation of VEGF, Ang2, ephrinB2 and EG-VEGF expression were analyzed to find the relations. The MVD was 146.69 +/- 77.79, 214.07 +/- 54.41, 32.85 +/- 8.49 and 34.83 +/- 8.29 in group A-D respectively with significant difference (F = 19.77, P = 0.000). The MVD in group A was higher than that in group C P = 0.006, but lower than that in group B P < or = 0.05 or 0.01. The expression levels of VEGF165, VEGF189, Ang2 and EG-VEGF mRNA were significantly different among the groups. The expression levels of VEGF165, Ang2 and EG-VEGF mRNA in group A were all higher than those in group C, but lower than those in group B P < 0.05 or 0.01. The MVD was significantly correlated with VEGF165, VEGF189, Ang2 and EG-VEGF mRNA with Spearman's related coefficient being 0.764, 0.510, 0.640 and 0.366 in HCC (P = 0.000, 0.000 0.000 and 0.003). In conclusion VEGF, Ang2 and EG-VEGF mRNA may play a role in angiogenesis and carcinogenesis of HCC. They can promote PVTT formation in HCC by modulating angiogenesis.     

Urocortin's inhibition of tumor growth and angiogenesis in hepatocellular carcinoma via corticotrophin-releasing factor receptor 2

Urocortin (UCN) functions via corticotrophin-releasing factor receptors (CRFRs), CRFR1 & 2. CRFR2 is reported to be a tonic suppressor of vascularization, implying its role in tumor angiogenesis. Here, it was found that UCN inhibited the growth of hepatocellular carcinoma (HCC) and reduced tumor microvessel density in nude mice. Hepatoma cells didn't express CRFRs whereas vessels expressed CRFRs, mainly CRFR2. In vitro three-dimensional culture assay showed UCN inhibited angiogenesis, this effect was abolished by CRFR2 antagonist, anti-sauvagine-30, demonstrating involvement of CRFR2. Furthermore, UCN inhibited the proliferation and promoted the apoptosis of endothelial cells and down-regulated VEGF expression in vivo via CRFR2.     

Angiogenesis and antiangiogenic therapy in hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is a hypervascular tumor characterized by neovascularization, which plays an important role in the growth and progression of HCC. Angiogenesis provides a target for novel prognostic and therapeutic approaches to HCC. Assessment of microvessel density using immunohistochemical staining for specific endothelial cell markers such as CD34 has been shown to provide prognostic information independent of conventional pathological parameters in HCC patients. Recent studies have unveiled the important angiogenic factors involved in the regulation of angiogenesis in HCC, although the exact molecular pathways are far from clear. Current data suggest that vascular endothelial growth factor (VEGF) plays a critical role in angiogenesis of HCC. Tumor expression of VEGF has been shown to correlate with tumor invasiveness and prognosis in patients with HCC. VEGF is an important molecular target for antiangiogenic therapy. Studies in animal models have demonstrated the efficacy of antiangiogenic agents such as anti-VEGF antibody and antagonists of VEGF receptors in suppressing hepatocarcinogenesis and growth of HCC. Antiangiogenic therapy has already entered clinical trials in HCC patients and holds the promise of providing an effective novel treatment for HCC, which is of great clinical significance because there is no existing effective systemic therapy for HCC.     

Monocyte chemoattractant protein-1 expression correlates with macrophage infiltration and tumor vascularity in human gastric carcinomas

The purpose of this study was to investigate the role of interactions between tumor cells and macrophages during angiogenesis in human gastric carcinomas. Macrophage infiltration into tumors and monocyte chemoattractant protein-1 (MCP-1) expression was assessed in 72 archival specimens of gastric carcinoma for comparison with tumor vascularity. The mRNA expression of MCP-1 was examined by RT-PCR in 6 gastric carcinoma cell lines and in fresh biopsy specimens from 18 patients. Immunolocalization of representative angiogenic factors, vascular endothelial growth factor (VEGF), and platelet-derived endothelial cell growth factor (PD-ECGF) was also done. MCP-1 expression in tumor cells increased with the depth of tumor invasion (Tis 9.5%, T1 19.4%, T2-4 60.0%), as did microvessel density and macrophage infiltration. Macrophage counts correlated with vessel counts, and both were significantly higher in MCP-1-positive than in negative tumors. Of the 6 gastric carcinoma cell lines, 2 constitutively expressed MCP-1 mRNA. In 6 (33.3%) of 18 biopsy samples, MCP-1 mRNA was expressed at higher levels in tumor tissues than in normal mucosa. VEGF protein was expressed by gastric carcinoma cells, whereas PD-ECGF protein was expressed mainly by stromal mononuclear cells. MCP-1 expression correlated significantly with VEGF but not PD-ECGF expression in gastric carcinomas. These results suggest that MCP-1 produced by human gastric carcinoma cells plays a role in angiogenesis via macrophage recruitment and activation.     

肝细胞癌中表皮生长因子与血管内皮生长因子过量表达的关系

目的　研究肝细胞癌 (HCC)中表皮生长因子 (EGF)与血管内皮生长因子 (VEGF)过量表达的关系。方法　通过免疫组化SABC法 ,检测 36例HCC组织及其相应癌旁肝组织和 6例正常肝组织中EGF、VEGF和微血管密度的表达 ,并对这些指标进行相关分析。离体实验中 ,用重组人EGF刺激人肝癌细胞系HepG2 ,采用半定量逆转录PCR检测VEGF的表达情况。结果　 36例HCC组织中 ,EGF和VEGF表达阳性率分别为 75 .0 %和 88.9%。Spearman等级相关分析显示 ,HCC组织中EGF的表达与VEGF的表达具有明显的正相关关系 (r=0 .4 6 2 ,P <0 .0 1)。重组人EGF可以以浓度和时间依赖性的方式诱导HepG2 细胞中VEGF的转录。结论　HCC中EGF的表达是VEGF过量表达的基本原因之一。     

Cyclooxygenase-2 pathway correlates with vascular endothelial growth factor expression and tumor angiogenesis in hepatitis B virus-associated hepatocellular carcinoma

Evidence indicates that cyclooxygenase (COX)-2-derived prostaglandins (PGs) contribute to tumor growth by inducing angiogenesis. We investigated the role of COX-2 in hepatitis B virus (HBV)-associated hepatocellular carcinoma (HCC). COX-2 and vascular endothelial growth factor (VEGF) expressions were examined by immunohistochemistry in 24 HBV-associated HCC. Tumor micro-vessel density (MVD) was assessed using CD34 immunohistochemistry. Hep3B HCC cell line, which carries integrated HBV genome, was stably transfected with human COX-2 cDNA. COX-2 and VEGF expressions were determined by Western blot while PG level was determined by ELISA. The effects of PGs on VEGF expression were also investigated. Expression of COX-2 and VEGF in HCC cells were observed in 19 (79%) and 16 (67%) cases, respectively. Well-differentiated HCC expressed COX-2 more strongly than less-differentiated HCC (p<0.001). COX-2 expression was found to correlate with VEGF expression and MVD (p=0.003 and 0.004, respectively). COX-2 overexpressing Hep3B clone had higher VEGF expression as compared to non-COX-2 expressing clone and parental cells. Treatment of the COX-2 overexpressing cells with a COX-2-selective inhibitor, NS-398 (10 microM), decreased PGE2 level and attenuated VEGF expression. Addition of PGE2 (10 microM) and the stable analog of PGI2, carbaprostacyclin (5 microM), to Hep3B cells also increased VEGF expression. Up-regulation of COX-2 correlates with VEGF expression and tumor angiogenesis in HBV-associated HCC. Moreover, COX-2 up-regulates VEGF expression in HCC cells, possibly via PGs production. Selective inhibition of COX-2 may block HCC associated angiogenesis and thus provides a rational approach for treatment of this malignancy.     

Twist overexpression correlates with hepatocellular carcinoma metastasis through induction of epithelial-mesenchymal transition.

PURPOSE: Hepatocellular carcinoma (HCC) is a rapidly growing tumor associated with a high propensity for vascular invasion and metastasis. Epithelial-mesenchymal transition (EMT) is a key event in the tumor invasion process. Recently, Twist has been identified to play an important role in EMT-mediated metastasis through the regulation of E-cadherin expression. However, the actual role of Twist in tumor invasiveness remains unclear. The purpose of this study is to investigate the expression and possible role of Twist in HCC. EXPERIMENTAL DESIGN: We evaluated Twist and E-cadherin expression in HCC tissue microarray of paired primary and metastatic HCC by immunohistochemical staining. The role of Twist in EMT-mediated invasiveness was also evaluated in vitro in HCC cell lines. RESULTS: We first showed that overexpression of Twist was correlated with HCC metastasis (P=0.001) and its expression was negatively correlated with E-cadherin expression (P=0.001, r=-0.443) by tissue microarray. A significant increase of Twist at the mRNA level was also found in metastatic HCC cell lines MHCC-97H, MHCC-97L, and H2M when compared with nonmetastatic Huh-7, H2P, and PLC cell lines. The MHCC-97H cell line, which has a higher metastatic ability, was found to have a higher level of Twist than MHCC-97L. Accompanied with increased Twist expression in the metastatic HCC cell lines when compared with the nonmetastatic primary ones, we found decreased E-cadherin mRNA expression in the metastatic HCC cell lines. By ectopic transfection of Twist into PLC cells, Twist was able to suppress E-cadherin expression and induce EMT changes, which was correlated with increased HCC cell invasiveness. CONCLUSION: This study shows that Twist overexpression was correlated with HCC metastasis through induction of EMT changes and HCC cell invasiveness.     

VEGF和MMP-9在食管癌中的表达及低氧调节

目的 研究血管内皮生长因子（VEGF）和基质金属蛋白酶－9（MMP－9）的表达与食管癌血管形成和临床的关系,以及低氧对其的调节作用。方法 用逆转录－聚合酶链式反应（RT－PCR）检测了42例食管癌手术标本（包括18例癌旁组织）中VEGF和MMP－9mRNA的表达,用免疫组化染色的方法检测了56例食管癌标本中VEGF蛋白的表达和平均血管密度（MVD）,同时用酶联免疫吸附试验（ELISA）的方法定量测定了低氧对食管癌细胞系中VEGF和MMP－9表达的影响。结果 食管癌中VEGF的表达显著高于癌旁组织,与肿瘤内平均MVD密切正相关,VEGF表达和肿瘤中MVD计数与食管癌的分期、淋巴结转移密切相关。食管癌中MMP－9的表达也显著高于癌旁组织,但MMP－9的表达与食管癌中的MVD计数和临床病理特征无关。低氧可以显著增加食管癌细胞系中VEGF的表达,但对MMP－9的表达无明显影响。结果 VEGF的表达可能在食管癌血管形成和转移中起重要作用,并受低氧调节,有可能作为反映食管癌进展的生物学指标和抗血管治疗的靶点。     

The expression of transforming growth factor-beta1 is significantly correlated with the expression of vascular endothelial growth factor and poor prognosis of patients with advanced gastric carcinoma.

BACKGROUND: Transforming growth factors beta (TGFs beta) are involved in a variety of important cellular functions, including cell growth and differentiation, adhesion, migration, extracellular matrix formation, and immune function. Moreover, it has been reported that TGFs beta are correlated with angiogenesis. However, the role of TGF-beta as an angiogenic factor in gastric carcinoma is still unclear. METHODS: TGF-beta1 expression was determined in 101 patients with gastric carcinoma by immunohistochemical procedures, and this expression was compared in the current study with both the expression of vascular endothelial growth factor (VEGF), which is thought to be the most potent angiogenic factor, and microvessel density, to evaluate the effect of TGF-beta1 on the angiogenesis of gastric carcinoma tissues. RESULTS: TGF-beta1 expression was detected in 23 tumors (22.8%). TGF-beta1 expression was more frequent in differentiated than in undifferentiated gastric carcinoma. Furthermore, TGF-beta1 expression was significantly correlated with the depth of invasion and the stage of disease. There was a close correlation between TGF-beta1 expression and VEGF expression. There was no correlation between TGF-beta1 expression and microvessel density, whereas VEGF expression was significantly correlated with microvessel density. With regard to prognosis, the 5-year survival rate was 55.9% for patients with TGF-beta1 positive tumors and 67.0% in patients with TGF-beta1 negative tumors. Accordingly, the prognosis for patients with TGF-beta1 negative tumors was significantly better than that for patients with TGF-beta1 positive tumors. Multivariate analysis indicated that lymph node metastasis, tumor size, and TGF-beta1 expression were independent prognostic factors. CONCLUSIONS: These results suggest that TGF-beta1 might be associated with tumor progression by indirectly stimulating angiogenesis through the up-regulation of VEGF expression in gastric carcinoma.