Platelet-derived endothelial cell growth factor expression correlates with tumour angiogenesis and prognosis in non-small-cell lung cancer.

Angiogenesis is a recently described prognostic factor in non-small-cell lung cancer. Platelet-derived endothelial cell growth factor (PD-ECGF), shown to be the enzyme thymidine phosphorylase (TP), induces angiogenesis in vitro and in vivo. High intracellular levels of the enzyme are associated with increased chemosensitivity to pyrimidine antimetabolites. PD-ECGF/TP expression was evaluated immunohistochemically in surgically resected specimens from 107 patients with operable non-small-cell lung cancer using the P-GF,44C monoclonal antibody. High expression of PD-ECGF/TP was found in 25% of cases and was associated with high vascular grade (P = 0.01). Fourteen of 32 (44%) high vascular grade tumours showed a positive reactivity for PD-ECGF/TP vs 13/75 (17%) of low/medium vascular grade. Positive expression was observed more frequently in T2-staged cases than in T1 (P = 0.04). While overall survival was not affected (P = 0.09), subset analysis revealed that node-negative patients with positive PD-ECGF/TP expression had a worse prognosis (P = 0.04). The results suggest that PD-ECGF/TP may be an important molecule involved in angiogenesis in non-small-cell lung cancer. Up-regulation of the enzyme defines a more aggressive tumour phenotype in patients with node-negative disease. Assessment of vascular grade and PD-ECGF/TP expression should be taken into account in the design of randomized trials assessing the role of adjuvant chemotherapy in non-small-cell lung cancer.     

子宫内膜癌组织中血管内皮生长因子与雌激素受体的表达及相关性探讨

目的:探讨子宫内膜癌组织中血管内皮生长因子( vascular endothelial growth fac tor, VEGF)和雌激素受体(estrogen receptor,ER)的表达、意义及两者的关系。方法:用免疫组化法检测30 例正常子宫内膜、30 例子宫内膜增生和50例子宫内膜癌中VEGF和ER的表达。结果:子宫内膜癌中VEGF表达强阳性率为64. 0%(32/50),明显高于正常内膜和增生内膜,两者阳性率均为0 (0/30),P 值均为0 .002 5;而ER表达阳性率为82. 0%(41/50),明显低于正常内膜和增生内膜,两者阳性率均为100 .0%(30/30),P 值均为0 .031。非内膜样癌中ER表达阳性率为50 0%(6/12),显著低于内膜样癌92. 1% (35/38),P= 0 .044; G3级内膜癌中ER表达阳性率为50. 0%(5/10),明显低于G1. 95 2% (20/21)和G2 级84 .2%(16/19),P 值分别为0. 045 和0 .039;Ⅲ期内膜癌ER表达阳性率为42 .9%(3/7),明显低于Ⅰ期93 .8%(30/32)和Ⅱ期,72. 7% (8/11),P值分别为0.. 029 和0 049。G3 级内膜癌中VEGF表达阳性率为100. 0%(10/10),明显高于G1 级76. 2% ( 16/21 ) 和G2 级84 .2%(16/19 ),P值分别为0 048和0 049;内膜癌中VEGF表达与组织学类型及手术病理分期差异无统计学意义,P= 0. 26。子宫内膜癌中VEGF 表达与ER 表达成负相关关系,r=-0 .421 6,tr=-3 .970 5,P=0.005 1。     

Energy intake and prostate tumor growth, angiogenesis, and vascular endothelial growth factor expression

BACKGROUND: A sedentary lifestyle coupled with excessive energy intake is speculated to be a factor associated with increased incidence of prostate cancer. We have investigated the effects of energy intake on prostate tumor growth in experimental animals. METHODS: Two transplantable prostate tumor models, i.e., the androgen-dependent Dunning R3327-H adenocarcinoma in rats and the androgen-sensitive LNCaP human carcinoma in severe combined immunodeficient mice, were studied. R3327-H tumor growth and relevant tumor biomarkers (proliferation index, apoptosis [programmed cell death], microvessel density, and vascular endothelial growth factor [VEGF] expression) were compared in ad libitum fed control rats, ad libitum fed castrated rats, and groups restricted in energy intake by 20% or 40%. A second set of experiments involving both tumor models examined tumor growth in ad libitum fed rats or in animals whose energy intake was restricted by 30% using three different methods, i.e., total diet restriction, carbohydrate restriction, or lipid restriction. All P values are two-sided. RESULTS: R3327-H tumors were smaller in energy-restricted or castrated rats than in control rats (P<.001). Tumors from energy-restricted rats exhibited changes in tumor architecture characterized by increased stroma and more homogeneous and smaller glands. In castrated rats, the tumor proliferation index was reduced (P<.0001), whereas apoptosis was increased in both energy-restricted (P<.001) and castrated (P<.001) rats. Tumor microvessel density and VEGF expression were reduced by energy restriction and castration (P<.003 versus control). Restriction of energy intake by reduction of carbohydrate intake, lipid intake, or total diet produced a similar inhibition of growth of R3327-H or LNCaP tumors. These effects were associated with reduced circulating insulin-like growth factor-I. CONCLUSIONS: Our observations are consistent with the hypothesis that energy restriction reduces prostate tumor growth by inhibiting tumor angiogenesis. Furthermore, dietary fat concentration does not influence prostate tumor growth when energy intake is reduced.     

Angiogenesis in cholangiocellular carcinoma: expression of vascular endothelial growth factor, angiopoietin-1/2, thrombospondin-1 and clinicopathological significance

Angiogenesis in cholangiocellular carcinoma (CCC) has rarely been investigated. The aim of this study was to determine the angiogenesis status of CCC and assess its relationship with angiogenic factors and clinicopathological characteristics. We examined 33 surgically resected CCC specimens. Tumor angiogenesis was assessed by microvessel density (MVD) using the anti-CD34 antibody, and the expression of VEGF, Ang-1, Ang-2, and TSP-1 was determined by immunohistochemistry. The mean (+/- SD) MVD was 87.2+/-52.6/mm2 (range, 0-229/mm2). A total of 75.6% cases were positive for VEGF expression, 36% for Ang-1, 57.6% for Ang-2 and 45.5% for TSP-1. VEGF and Ang-2 expression was associated with a significantly higher level of MVD (p=0.004 and 0.015, respectively). TSP-1 expression was associated with a significantly lower level of MVD (p=0.005) and a higher level of intrahepatic metastasis (46.7% vs. 5.6%, p=0.012). There was no significant correlation between VEGF, Ang-1, Ang-2, and TSP-1 expression and tumor size, capsule formation, infiltration of capsule, portal vein invasion, intrahepatic metastasis or CCC differentiation. There was no significant correlation between MVD levels, VEGF, Ang-1, Ang-2, and TSP-1 expression and postoperative survival. A considerable degree of angiogenesis, comparable to that of other solid tumors, was observed in CCC. VEGF and Ang-2 might play a proangiogenic role, and TSP-1 may play an inhibitory role in CCC. Although TSP-1 may increase intrahepatic CCC metastases, neither MVD levels nor the expression of VEGF, Ang-1, or Ang-2 was associated with clinicopathological factors and prognosis.     

Endothelin-1-, endothelin-A-, and endothelin-B-receptor expression is correlated with vascular endothelial growth factor expression and angiogenesis in breast cancer.

PURPOSE: Endothelin-1 (ET-1) and its receptors (ET(A)R and ET(B)R), referred to as the endothelin (ET) axis, are overexpressed in breast carcinomas, and influence tumorigenesis and tumor progression by various mechanisms, including angiogenesis. The objective of the study was to clarify if expression of the ET axis participates in angiogenesis of breast carcinoma EXPERIMENTAL DESIGN: We analyzed expression of ET-1, ET(A)R, ET(B)R, and vascular endothelial growth factor (VEGF) immunohistochemically in 600 tissue array specimens from 200 paraffin-embedded breast carcinomas performing tissue microarray technology. Microvessel density (MVD) was determined by counting microvessels (identified by factor VIII) in each core specimen. RESULTS: Moderate or strong immunostaining was observed for ET-1 in 25.4%, for ET(A)R in 43.7%, and for ET(B)R in 22.2% of breast carcinomas. Of all cases, 44.7% showed significant expression of VEGF. MVD varied between different tumor specimens (range, 0-80; median, 17). We observed a statistically significant correlation between MVD and ET expression status with higher MVD in ET-positive tumors. Moreover, expression of VEGF was found more frequently in tumors with overexpression of the ET axis (each P < 0.001). Staining of VEGF was correlated positively with MVD CONCLUSIONS: These results indicate that increased ET-1, ET(A)R, and ET(B)R expression is associated with increased VEGF expression and higher vascularity of breast carcinomas and, thus, could be involved in the regulation of angiogenesis in breast cancer. Our findings provide evidence that the expression pattern of the ET-axis and in particular of ET(A)R may have clinical relevance in future antiangiogenic targeted therapies for breast cancer.     

Site-dependent expression of vascular endothelial growth factor, angiogenesis and proliferation in human gastric carcinoma

To determine the role of site of tumor implantation on tumor angiogenesis, we implanted gastric cancer cells in the orthotopic (stomach) and ectopic (subcutaneous) locations in nude mice. Tumors in the stomach demonstrated greater vascularization, higher levels of vascular endothelial growth factor (VEGF) expression, and greater proliferation compared with tumors in the subcutaneous tissues. These data suggest that the relationships among the expression of VEGF, vascularization, and proliferation of human gastric cancer cells are regulated by the organ microenvironment. In addition, VEGF may provide a target for anti-angiogenic therapy for gastric cancers.     

骨肉瘤血管内皮生长因子表达与肿瘤血管生成及预后的关系

目的：研究血管内皮生长因子（ＶＥＧＦ）表达与骨肉瘤血管生成和预后的关系。方法：应用免疫组化和形态计量方法，检测８０例骨肉瘤ＶＥＧＦ表达和肿瘤微血管密度。结果：骨肉瘤ＶＥＧＦ表达（－）级者６例，（±）级者１０例，（＋）级者２２例，（＋＋）级者４２例。ＶＥＧＦ表达与肿瘤体积、Ｄａｈｌｉｎ’ｓ分型和Ｐｒｉｃｅ’ｓ分级无关，但与肿瘤微血管计数相关（Ｐ〈０．０５）。ＶＥＧＦ高表达组（＋＋）级多见于骨样组织幼     

Role of the vascular endothelial growth factor pathway in tumor growth and angiogenesis.

New blood vessel formation (angiogenesis) is a fundamental event in the process of tumor growth and metastatic dissemination. Hence, the molecular basis of tumor angiogenesis has been of keen interest in the field of cancer research. The vascular endothelial growth factor (VEGF) pathway is well established as one of the key regulators of this process. The VEGF/VEGF-receptor axis is composed of multiple ligands and receptors with overlapping and distinct ligand-receptor binding specificities, cell-type expression, and function. Activation of the VEGF-receptor pathway triggers a network of signaling processes that promote endothelial cell growth, migration, and survival from pre-existing vasculature. In addition, VEGF mediates vessel permeability, and has been associated with malignant effusions. More recently, an important role for VEGF has emerged in mobilization of endothelial progenitor cells from the bone marrow to distant sites of neovascularization. The well-established role of VEGF in promoting tumor angiogenesis and the pathogenesis of human cancers has led to the rational design and development of agents that selectively target this pathway. Studies with various anti-VEGF/VEGF-receptor therapies have shown that these agents can potently inhibit angiogenesis and tumor growth in preclinical models. Recently, an anti-VEGF antibody (bevacizumab), when used in combination with chemotherapy, was shown to significantly improve survival and response rates in patients with metastatic colorectal cancer and thus, validate VEGF pathway inhibitors as an important new treatment modality in cancer therapy.     

Hypoxia-induced angiogenesis and vascular endothelial growth factor secretion in human melanoma.

Tumour cells exposed to hypoxia in vitro can show increased expression of several selected genes, including the gene encoding the vascular endothelial growth factor (VEGF), suggesting that hypoxia followed by reoxygenation might promote the malignant progression of tumours. An in vitro/in vivo study was conducted to investigate whether hypoxia can increase the angiogenic potential of tumour cells through increased VEGF secretion. Four human melanoma cell lines (A-07, D-12, R-18, U-25) were included in the study. Cell cultures were exposed to hypoxia (oxygen concentration <10 p.p.m.) in vitro using the steel chamber method. Rate of VEGF secretion was measured in vitro in aerobic and hypoxic cell cultures by ELISA. Angiogenesis was assessed in vivo using the intradermal angiogenesis assay. Aliquots of cells harvested from aerobic cultures or cultures exposed to hypoxia for 24 h were inoculated intradermally in the flanks of adult female BALB/c-nu/nu mice. Tumours developed and angiogenesis was quantified by scoring the number of capillaries in the dermis oriented towards the tumours. The number of tumour-oriented capillaries did not differ significantly between tumours from hypoxic and aerobic cultures for A-07 and U-25, whereas tumours from hypoxic cultures showed a larger number of tumour-oriented capillaries than tumours from aerobic cultures for D-12 and R-18. The VEGF secretion under aerobic conditions and the absolute increase in VEGF secretion induced by hypoxia were lower for D-12 and R-18 than for A-07 and U-25, whereas the relative increase in VEGF secretion induced by hypoxia was higher for D-12 and R-18 than for A-07 and U-25. VEGF is not a limiting factor in the angiogenesis of some tumours under normoxic conditions. Hypoxia can increase the angiogenic potential of tumour cells by increasing the secretion of VEGF, but only of tumour cells showing low VEGF secretion under normoxia. Transient hypoxia might promote the malignant progression of tumours by temporarily increasing the angiogenic potential of tumour cells showing low VEGF expression under normoxic conditions.     

血管内皮生长因子及微血管密度在乳腺癌中的表达及意义

目的 研究血管内皮生长因子(VEGF)及微血管密度(MVD)在乳腺癌组织中的表达及意义。方法 应用免疫组化SP法检测81例原发性乳腺癌患者癌组织MVD和VEGF的表达。结果 VEGF高表达者49例(60．5％)，MVD计数高者35例(43．2％)。VEGF、MVD与肿瘤TNM分期有关，但与年龄、肿瘤大小、雌激素受体(ER)表达及淋巴结状况无关；VEGF与MVD的表达有显著相关性。单因素预后分析显示，MVD及VEGF低表达者无病生存期(DFS)及总生存期(OS)长于高表达者。分组的单因素分析表明，VEGF与各组患者的DFS有显著相关性，与淋巴结( )和Ⅲ期乳腺癌患者的OS有显著相关性；而MVD与淋巴结( )患者的DFS和OS以及Ⅲ期乳癌患者的DFS有显著相关性。多元回归分析显示，MVD是风险因子，表达越高生存期越短。结论 VEGF和MVD均为判断乳腺癌须后的有效指标，其中MVD可能是预测乳腺癌预后的独立因子。     

Cyclooxygenase-2 upregulates vascular endothelial growth factor expression and angiogenesis in human gastric carcinoma

Although gastric cancer with cyclooxygenase (COX)-2 overexpression is associated with poor prognosis, the mechanistic pathway remains unknown. We examined the associations between expressions of COX-2 and vascular endothelial growth factor (VEGF) in both gastric cancer cells and in human gastric cancer. The gastric cell line, Kato III, was transiently transfected with cox-2 expressing vector. The levels of COX-2, prostaglandin (PG) E2 and VEGF expression were measured post-transfection. Additionally, expressions of COX-2 and VEGF in human gastric cancer were determined by immunohistochemistry in archive gastrectomy specimens. Tumor angiogenesis was assessed by the microvessel density (MVD), which was determined by anti-CD34 immunostaining. Transient transfection of Kato III with cox-2 was associated with increased COX-2 expression, higher PGE2 production and upregulated VEGF expressions. Treatment with NS398, a specific COX-2 inhibitor, reduced VEGF expression in COX-2 expressing Kato III cells by 25%. Among the 67 gastric cancers examined, COX-2 overexpression was found in 45 (67%) cases whereas increased VEGF expression was detected in 46 (69%) cases. There was a significant association between COX-2 and VEGF expressions in gastric cancer (r=0.25, p=0.041). Additionally, tumor MVD was associated with both COX-2 (r=0.32, p=0.008) and VEGF (r=0.39, p=0.001) expressions. Our results showed that overexpression of COX-2 in both gastric cells and primary gastric cancer is associated with upregulation of VEGF and angiogenesis. Future studies should evaluate the potential anti-angiogenic effect of COX-2 inhibitors on human gastric cancer.     

术前化疗对乳腺癌组织VEGF表达和血管生成的影响

目的研究术前化疗对乳腺癌血管内皮生长因子(VEGF)表达、肿瘤组织微血管密度的影响.方法36例术前化疗的乳腺癌和32例未做术前化疗的乳腺癌标本,进行VEGF、CD34免疫组织化学标记,并进行微血管计数和统计学处理.结果术前化疗组VEGF阳性率为47.22%(17/36),对照组53.13%(17/32),微血管计数化疗组和对照组分别为23.67±13.45,26.12±11.32,两者差异均无显著性.化疗组VEGF阳性和阴性的标本,MVC均值差异无显著性;对照组VEGF阳性和阴性的标本,MVC均值差异有显著性.结论常规术前化疗并未显示出明显的血管生成抑制作用,也未显示出明显的血管内皮生长因子表达的改变.     

Tenascin-C regulates angiogenesis in tumor through the regulation of vascular endothelial growth factor expression

In order to verify whether tenascin-C (TN-C) is involved in angiogenesis as an extracellular signal molecule during tumorigenesis, cancerous cell transplantation experiments and coculture experiments were carried out, focusing on the regulation of vascular endothelial growth factor (VEGF). The A375 human melanoma cells introduced the GFP gene (A375-GFP), implanted subcutaneously into BALB/cA nude (WT) and TN-C knockout BALB/cA nude (TNKO) congenic mice. Furthermore, coculture experiments between A375-GFP and embryonic mesenchyme, which was prepared from both genotypes, were carried out to investigate the molecular mechanism in the cell-cell interactions. Both the content of TN-C and that of VEGF in the tumor and the conditioned medium were analyzed by the sandwich ELISA method. Seven days after transplantation of the A375-GFP, capillary nets became far more abundant in the tumors grown in WT mice than those in TNKO mice. Interestingly, VEGF and TN-C expressions showed antithetical expression patterns between the tumors in WT mice and those in TNKO mice. This peculiar phenomenon seems to be caused by a time lag prior to the onset of the mesenchymal regulation for the TN-C expression of A375-GFP. The coculture experiments revealed that WT mesenchyme had a much stronger effect than TNKO mesenchyme on both TN-C and VEGF expression. However, the defects of TNKO mesenchyme were restored in all cases by additional TN-C. These results clearly indicated that the expressions of both TN-C and VEGF depend on the surrounding mesenchyme, and that the function of mesenchyme is regulated by its own mesenchymal TN-C. In conclusion, the present data suggest that the matrix microenvironment organized by the host mesenchyme is very important for angiogenesis in tumor development.     

Expression of hypoxia-inducible factor (HIF)-1alpha is associated with vascular endothelial growth factor expression and tumour angiogenesis in human oesophageal squamous cell carcinoma

The purpose of this study was to examine the relationship between hypoxia inducible factor (HIF)-1alpha expression, vascular endothelial growth factor (VEGF) expression, and tumour vascularity in squamous cell carcinoma of the oesophagus. Expression of HIF-1alpha and VEGF was examined in two oesophageal squamous cell carcinoma cell lines (TE2, TE3) and 82 archival surgical specimens of human oesophageal squamous cell carcinoma tissue. In both cell lines, the levels of HIF-1alpha protein and VEGF mRNA were increased under hypoxic conditions. Thirty-two of the 82 (39%) tumour specimens showed high levels of HIF-1alpha immunoreactivity in the nuclei and/or cytoplasm of cancer cells. HIF-1alpha expression correlated significantly with venous invasion, VEGF expression, and microvessel density. Among the 47 patients who did not receive pre-operative chemotherapy, the outcome of those with high HIF-1alpha-expressing tumours was significantly poorer than that of those with low HIF-1alpha-expressing tumours. These results suggest that HIF-1alpha and VEGF expression are important determinants of survival in squamous cell carcinoma of the oesophagus.     

Purinergic regulation of vascular endothelial growth factor signaling in angiogenesis

P2Y purine nucleotide receptors (P2YRs) promote endothelial cell tubulogenesis through breast cancer cell-secreted nucleoside diphosphate kinase (NDPK). We tested the hypothesis that activated P2Y₁ receptors transactivate vascular endothelial growth factor receptor (VEGFR-2) in angiogenic signaling. P2Y₁R stimulation (10 μM 2-methyl-thio-ATP (2MS-ATP)) of angiogenesis is suppressed by the VEGFR-2 tyrosine kinase inhibitor, SU1498 (1 μM). Phosphorylation of VEGFR-2 by 0.0262 or 2.62 nM VEGF was comparable with 0.01 or 10 μM 2MS-ATP stimulation of the P2Y₁R. 2MS-ATP, and VEGF stimulation increased tyrosine phosphorylation at tyr1175. 2MS-ATP (0.1–10 μM) also stimulated EC tubulogenesis in a dose-dependent manner. The addition of sub-maximal VEGF (70 pM) in the presence of increasing concentrations of 2MS-ATP yielded additive effects at 2MS-ATP concentrations <3 μM, whereas producing saturated and less than additive effects at ⩾3 μM. We propose that the VEGF receptor can be activated in the absence of VEGF, and that the P2YR–VEGFR2 interaction and resulting signal transduction is a critical determinant of vascular homoeostasis and tumour-mediated angiogenesis.     

Clinical and biological significance of vascular endothelial growth factor in endometrial cancer.

PURPOSE: Vascular endothelial growth factor (VEGF) is critical for angiogenesis and tumor progression; however, its role in endometrial cancer is not fully known. Therefore, we examined the clinical and therapeutic significance of VEGF in endometrial carcinoma using patient samples and an endometrioid orthotopic mouse model. EXPERIMENTAL DESIGN: Following Institutional Review Board approval, VEGF expression and microvessel density (MVD) counts were evaluated using immunohistochemistry in 111 invasive endometrioid endometrial cancers by two independent investigators. Results were correlated with clinicopathologic characteristics. For the animal model, Ishikawa or Hec-1A cancer cell lines were injected directly into the uterine horn. Therapy experiments with bevacizumab alone or in combination with docetaxel were done and samples were analyzed for markers of angiogenesis and proliferation. RESULTS: Of 111 endometrial cancers, high expression of VEGF was seen in 56% of tumors. There was a strong correlation between VEGF expression and MVD (P < 0.001). On multivariate analysis, stage (P = 0.04), grade (P = 0.003), VEGF levels (P = 0.03), and MVD (P = 0.037) were independent predictors of shorter disease-specific survival. In the murine model, whereas docetaxel and bevacizumab alone resulted in 61% to 77% tumor growth inhibition over controls, combination therapy had the greatest efficacy (85-97% inhibition over controls; P < 0.01) in both models. In treated tumors, combination therapy significantly reduced MVD counts (50-70% reduction over controls; P < 0.01) and percent proliferation (39% reduction over controls; P < 0.001). CONCLUSIONS: Increased levels of VEGF and angiogenic markers are associated with poor outcome in endometrioid endometrial cancer patients. Using a novel orthotopic model of endometrioid endometrial cancer, we showed that combination of antivascular therapy with docetaxel is highly efficacious and should be considered for future clinical trials.