血小板反应素-4在胃癌中的表达及其临床意义

目的定量测定血小板反应素-4(TSP-4)基因在胃癌及癌旁组织中的表达,探讨其与胃癌临床病理学特征、微血管密度(MVD)和基质金属蛋白酶-9(MMP-9)表达水平的关系,评价其在胃癌发生和发展中的意义。方法采用RT-PCR技术检测82例配对的胃癌组织及癌旁组织TSP-4mRNA的表达,并分析其与临床病理学特征的关系;通过免疫组织化学检测肿瘤组织中CD34和MMP-9的表达,分析TSP-4mRNA的表达与肿瘤微血管密度、MMP-9表达的相关性。结果TSP-4mRNA在胃癌中的表达高于癌旁组织(P=0.03);胃癌组织中TSP-4mRNA的表达水平与肿瘤大小、组织分型、淋巴结转移、肿瘤微血管密度及MMP-9表达密切相关(P=0.002,P=0.031,P=0.014,r=0.67P0.01,P=0.008),但与性别、年龄及侵袭程度无关(P=0.53,P=0.57,P=0.15)。结论TSP-4可能通过调节胃癌新血管生成和MMP-9的表达,促进肿瘤生长与转移。     

Microvessel density, vascular endothelial growth factor and its receptors Flt-1 and Flk-1/KDR in hepatocellular carcinoma.

Assessment of angiogenesis may yield important information for an effective antiangiogenic treatment for hepatocellular carcinoma (HCC) because HCC is characteristically hypervascular We examined the relationship of microvessel density (MVD), vascular endothelial growth factor (VEGF), and VEGF receptors Flt-1 and Flk-1/KDR in 50 patients with HCC and in 3 hepatoma cell lines. VEGF messenger RNA (mRNA) was overexpressed in 26 tumors (52%), and the 3 VEGF isoforms (121, 165, and 189) were present in high frequencies. Flt-1 mRNA was overexpressed in 34 tumors (68%), with levels significantly increased in HCCs compared with the nontumorous livers. Tumor Flt-1 mRNA significantly correlated with tumor VEGF mRNA levels. Within the group of tumors 8.5 cm or less in diameter, tumors with intrahepatic metastasis in the form of tumor microsatellite formation had significantly higher VEGF mRNA levels. MVD assessed by immunohistochemical analysis with CD34 antibody was inversely related to tumor size. Angiogenesis as assessed by MVD and tumor VEGF expression seems to have a more important role in tumor growth and intrahepatic metastasis in smaller HCCs. The differential up-regulation of Flt-1 suggests that it may have an important role in angiogenesis in HCC.     

血小板反应蛋白-1及受体CD36在肝细胞性肝癌中的表达及意义

目的：研究肝细胞性肝癌(HCC)中血小板反应蛋白-1及受体CD36的表达及其与侵袭转移和血管生成的关系。 方法： 应用逆转录聚合酶链反应（RT-PCR）和免疫组织化学（SP法）法检测43例肝癌和癌旁组织中血小板反应蛋白-1、CD36的表达、CD34标记微血管密度，并分析其与肝癌临床病理特征及相互之间的关系。 结果： 肝癌中血小板反应蛋白-1的阳性率低于癌旁组织, 与有癌栓、包膜不完整、侵袭转移能力强呈负相关；CD36的表达与有癌栓、侵袭转移能力强呈负相关，两者呈正相关，并且两者阳性组的微血管密度均显著低于阴性组。 结论： 血小板反应蛋白-1可抑制肝癌的生长、延缓侵袭转移、抑制血管生成，受体CD36可能是血小板反应蛋白-1的作用途径之一。     

Expression of vascular endothelial growth factor and thrombospondin-1 in colorectal carcinoma

Solid tumors require neovascularization for growth and metastasis. Vascular endothelial growth factor (VEGF) is a well-characterized inducer of angiogenesis, while, thrombospondin-1 (TSP-1) is thought to be an antiangiogenic factor. In this study, we examined the expressions of these antigens and their relationship with microvessel density, and determined their prognostic significance. One hundred specimens resected from patients with colorectal adenocarcinoma were examined using immunohistochemical methods. Microvessel density, determined by immunostaining for factor VIII-related antigen, was significantly higher in tumors that were VEGF-positive and TSP-1-negative than in other tumors. Patients with VEGF-positive tumors had a significantly worse prognosis than did those with VEGF-negative tumors, and TSP-1 expression was inversely correlated with prognosis. The frequency of hepatic recurrence was significantly higher in patients with tumors that were VEGF-positive and TSP-1-negative than in all other patients. In conclusion, VEGF and TSP-1 are important regulators of tumor angiogenesis, and combined analysis of VEGF and TSP-1 may be useful for predicting recurrence in patients with colorectal adenocarcinoma.     

Microvessel density in pituitary adenomas and carcinomas

Tumor growth depends on several factors, including angiogenesis. Tumors cannot grow if new vessels are not formed to supply the cells with oxygen and other nutrients and to remove waste products. Increased angiogenesis can be correlated with tumor growth and metastatic potential in many tumor types, indicating that neoformation of vessels is a prognostic indicator of tumor behavior. We evaluated microvessel densities in 157 various pituitary adenoma types and seven pituitary carcinomas using immunocytochemistry for CD-34 antigen, a reliable marker of endothelial cells. The lowest percentage of microvessel density was found in growth hormone-producing adenomas, the highest level in pituitary carcinomas. In general, no major correlation was found between MIB-1 index (an indicator of cell proliferation) and microvessel density. The statistical study also demonstrated no gender-dependent changes in the microvessel density of pituitary tumors. Although the microvessel density was not significantly different in relation to invasiveness of pituitary tumors, our results demonstrate a tendency of invasive pituitary tumors to be more highly vascularized than non-invasive ones. Dopamine agonist and long-acting somatostatin analog treatment compared with untreated tumors did not significantly affect microvessel densities. Statistical differences were demonstrated in the microvessel density of macroadenomas between patients older and patients younger than 40 years. Significant differences were also apparent in the microvessel densities between microadenomas and macroadenomas diagnosed in young patients but not in the older age group. The strongly positive correlation observed between microvessel density and age is consistent with the view that age of the host may have an influence on the extent of neovascularization of pituitary adenomas.     

Thrombospondin-1 (TSP-1) up-regulates tissue inhibitor of metalloproteinase-1 (TIMP-1) production in human tumor cells: Exploring the functional significance in tumor cell invasion

Thrombospondin-1 (TSP-1), a matrix-bound adhesive glycoprotein, has been shown to modulate tumor progression. We previously demonstrated that TSP-1 up-regulates matrix metalloproteinases MMP-2 and MMP-9. Our studies suggested that the balance between MMPs and tissue inhibitors of metalloproteinases (TIMPs) is a key determinant in tumor cell invasion. We now report that TSP-1 up-regulates TIMP-1 expression in both human breast and prostate cancer cell lines. The effect of TSP-1 on TIMP-1 expression was examined in human breast adenocarcinoma cell lines (MDA-MB-231) and human prostate cancer cell lines (PC3-NI and PC3-ML) treated with exogenous TSP-1. TIMP-1 expression was also examined in TSP-1 stably transfected breast cancer cell line (MDA-MB-435). Northern and western blot analysis revealed TIMP-1 mRNA and TIMP-1 protein expression increased with increasing concentrations of TSP-1. This effect was inhibited by antibodies against the type I repeat domain of TSP-1 further suggesting that TSP-1 mediates TIMP-1 secretion. Inhibition of TSP-1 induced TIMP-1 levels increased tumor cell invasion. We conclude that TSP-1 is involved in influencing the critical balance between MMPs and their inhibitors, maintaining the controlled degradation of the extracellular matrix needed to support metastasis and our results may provide an explanation for the divergent activities reported for TSP-1 in tumor progression.     

Vascular endothelial growth factor expression, angiogenesis, and necrosis in renal cell carcinomas

Rapidly growing tumors often develop necrosis. In the present study the expression of vascular endothelial growth factor (VEGF) was investigated and compared to microvessel density and necrosis of renal cell carcinomas. In the tumor-host interface the microvessel density was significantly increased compared to central tumor areas. Tumor necrosis was associated with a decrease of microvessel density and an increase of the VEGF protein expression within the perinecrotic rim. VEGF protein was focally upregulated in vital tumor tissue. An increase of the apoptotic rate of endothelia and vital tumor tissue in tumors with necrosis could not be detected. VEGF(121,165) mRNA was decreased in proliferatively active carcinomas compared to less proliferative tumors. Multicellular renal cell cancer spheroids as a model of chronic hypoxia developed central apoptosis but no necrosis. VEGF was upregulated in the spheroid. Tumor microvessels expressed matrix metalloproteinase -2 and -9 and an incomplete pericyte covering in comparison to tumor-free tissue indicating immature active angiogenesis. We conclude that highly proliferative renal cell carcinomas outgrow their vascular supply and develop chronic hypoxia inducing a decrease of proliferation and an increase of VEGF expression. However, chronic hypoxia does not cause significant necrosis or apoptosis. Tumor necrosis is more likely induced by acute hypoxia due to immature microvessels. Furthermore, VEGF expression associated with concomitant tumor necrosis may help identify renal cell carcinomas susceptible to antiangiogenic therapy.     

Triggering the induction of myofibroblast and fibrogenesis by airway epithelial shedding

Myofibroblasts have been thought to participate in subepithelial fibrosis in asthma, but the mechanism of myofibroblast induction has not been fully understood. In this study we investigated injury-related myofibroblast induction in a coculture system of guinea-pig epithelial cells and fibroblasts cocultured in a human amnion chamber. After pseudostratified epithelial cells were mechanically scraped, migrated flat epithelial cells differentiated into cuboidal appearances on Day 4 and then returned to their original shapes on Day 8. During the course of the epithelial redifferentiation, it was found by Northern blot analysis, immunohistochemistry for alpha-smooth muscle actin, and electron microscopic observation that the myofibroblasts were transiently induced on Day 4. The myofibroblast induction was inhibited by the blocking of transforming growth factor (TGF)-beta1 and thrombospondin (TSP)-1, indicating that the activation of TGF-beta1 by TSP-1 would induce myofibroblasts. This finding was also supported by a transient upregulation of TSP immunoreactivity and TSP-1 messenger RNA (mRNA) in fibroblasts. Interestingly, epithelial injury reduced TGF-beta1 immunoreactivity in the amnion membrane but did not affect TGF-beta1 mRNA in epithelial cells and fibroblasts, indicating that TGF-beta1 supplied from the extracellular matrix can participate in myofibroblast induction. Concurrently with myofibroblast induction, procollagen type I and III mRNAs were upregulated in fibroblasts, and obvious collagen deposition was observed ultrastructurally around the myofibroblasts compared with the fibroblasts. These results indicate that induced myofibroblasts can be functionally more active in producing collagen than are resting fibroblasts. The present study suggests that epithelial injury stimulates TGF-beta1 release from the extracellular matrix and its activation via TSP-1 production, causing collagen synthesis through myofibroblast induction.     

Coexpression of heparanase, basic fibroblast growth factor and vascular endothelial growth factor in human esophageal carcinomas

Heparan sulfate (HS), which is degraded by heparanase, plays an important role in cell adhesion, insolubility of the extracellular matrix (ECM) and as a reservoir for various growth factors such as basic fibroblast growth factor (bFGF) and vascular endothelial growth factor (VEGF). In the present study, we examined the immunohistochemical expression of heparanase, bFGF and VEGF, and evaluated the correlation between their expression and microvessel density (MVD) in human esophageal carcinomas. Heparanase, bFGF and VEGF were immunolocalized predominantly to the carcinoma cells, but they were also localized to the endothelial cells of microvessels near the carcinoma cell nests. In carcinomas with invasion of the muscular layer or adventitia, heparanase staining was stronger at the invasive areas of carcinomas than the intraepithelial spread. Expression of heparanase and bFGF and the degree of MVD were associated with tumor invasion, lymph node metastasis and pathological stages. Cases with positive staining for heparanase, bFGF or VEGF tended to have a higher MVD than those without staining, and carcinomas with concomitant expression of heparanase, bFGF and VEGF showed the highest MVD. The level of heparanase mRNA expression was directly correlated with the MVD. In addition, heparanase-positive cases had a higher positive ratio of bFGF and VEGF compared with the heparanase-negative cases. These data suggest the possibility that heparanase may contribute to not only cancer cell invasion but also angiogenesis probably through degradation of HS in the ECM and release of bFGF and VEGF from the HS-containing ECM.     

VEGF、ANG-1、ANG-2、TSP-1的表达与胆管细胞性肝癌血管生成和侵润转移的关系

目的：研究血管内皮生长因子（VEGF）、血管生成素-1（ANG-1）、血管生成素-2（ANG-2）、血小板反应蛋白-1（TSP-1）的表达与胆管细胞性肝癌(CCC)血管生成和侵润转移的关系。方法： 对33例手术切除的CCC标本进行CD34、VEGF、 ANG-1、 ANG-2 和TSP-1的免疫组化染色，研究VEGF、ANG-1、ANG-2、TSP-1的表达与胆管细胞性肝癌血管生成和肿瘤门静脉侵犯、肝内转移、淋巴结转移以及肿瘤分化水平之间的关系。 结果： 本组CCC的微血管密度（MVD）为(87.2±52.6)/mm2，VEGF、ANG-1、ANG-2 和TSP-1的阳性率分别为75.6%、36.0%、57.6%和45.5%。VEGF和ANG-2的阳性表达与高MVD相关，TSP-1则与MVD负相关（P<0.01,P<0.05,P<0.01）。阳性TSP-1与肝内转移正相关（46.7% vs 5.6%，P<0.05）。结论： CCC瘤内的血管新生活跃，VEGF和ANG-2的阳性表达与CCC血管生成正相关，TSP-1则与其负相关，TSP-1的阳性表达还与肝内转移相关，VEGF、ANG-1、ANG-2的表达与肿瘤的侵润转移未见显著相关。     

Angiogenic switch during tumor progression of carcinoma ex-pleomorphic adenoma

We analyzed the tumor vascularization in carcinomas ex-pleomorphic adenoma (CXPA) to investigate the angiogenic switch during the malignant transformation of pleomorphic adenoma (PA) to carcinoma and during tumor progression. In eight cases of early CXPA (intracapsular and minimally invasive tumors), eight of advanced CXPA (widely invasive tumors), and ten of PA without malignant transformation, tumor vascularization was assessed in histological samples by measuring total microvascular area (TVA) and microvessel density (MVD) using CD34 and CD105 antibodies. MVD for CD105 increased significantly during tumor progression, whereas this was not the case for CD34 MVD. Comparing widely invasive CXPA with and without myoepithelial differentiation, CXPA with myoepithelial differentiation showed a significantly lower number of CD105 positive vessels but revealed higher TVA values. In these tumors, the neoplastic cells usually formed larger hypovascularized aggregates that were often surrounded by large-sized vessels. In conclusion, the antibody CD105 reveals an angiogenic switch during the progression from adenoma to carcinoma in salivary glands. The degree of angiogenesis and the total vascular area have distinctive patterns in CXPA with and without myoepithelial differentiation. Low angiogenesis associated with high TVA value is more characteristic of CXPA with myoepithelial differentiation.     

缺氧诱导因子-1α在结直肠腺癌中的表达及意义

目的　观察低氧培养条件下人结肠腺癌SW4 80细胞及人结直肠腺癌组织中缺氧诱导因子 1α(HIF 1α)mRNA、蛋白表达 ,探讨HIF 1α在结直肠腺癌中的表达及在肿瘤血管形成中的作用。方法　免疫组织化学链霉素抗生物素蛋白 过氧化物酶法 (SP法 )检测SW4 80细胞及结直肠腺瘤、腺癌组织中HIF 1α、血管内皮生长因子 (VEGF)蛋白表达 ;采用CD34标记血管内皮细胞计数微血管密度 (MVD)。用蛋白印迹法检测SW4 80细胞HIF 1α蛋白表达 ;原位杂交检测HIF 1αmRNA。结果　RT PCR结果显示 :低氧组SW4 80细胞HIF 1αmRNA表达显著升高 ,为常氧组的 2 33倍。低氧 genistein组HIF 1αmRNA表达为常氧组的 5 0 7%。原位杂交结果表明 :HIF 1αmRNA表达低氧组 (0 16 2 8± 0 0 0 85 )显著高于常氧组 (0 12 0 1± 0 0 0 38)和低氧 genistein组 (0 115 4± 0 0 0 5 6 ,P <0 0 5 )。免疫细胞化学染色显示 ,低氧组细胞HIF 1α、VEGF蛋白表达水平显著高于常氧组 (P <0 0 1,P <0 0 5 )和低氧 genistein组 (P <0 0 1,P <0 0 5 )。蛋白印迹结果显示 :低氧组HIF 1α蛋白表达显著高于常氧组 ,为常氧组 3 5 4倍。低氧 genistein组HIF 1α蛋白约为常氧组的 5 8 9%。结直肠腺瘤和腺癌HIF 1αmRNA阳性表达率分别为 38 9% (7/     

CD34 microvessel density and VEGF expression in basal and squamous cell carcinoma

Angiogenesis is a central process in the growth of solid tumors. The purpose of our study was to analyze the angiogenic pattern in squamous and basal cell carcinomas and to point out differences in microvessel density that could explain their different biological behaviour. Thirty-nine skin tumors (26 basal and 13 squamous cell carcinomas) were analyzed. In all samples, the microvessels density (MVD) and the levels of vascular endothelial growth factor mRNA (VEGFmRNA) were analyzed, together with the inter-relationship between these two variables. Using the median value of the entire series (33 vessels per 2.22 mm2), tumors with low and high MVD were identified. The majority of cancers with high vascularization belonged to the squamous histotype (12 of 39), while 19 of the 26 basal cell carcinomas showed a lower number of microvessels than the median value (p = 0.0001). The median value of VEGFcDNA quantitation allowed us to distinguish tumors with high VEGF expression (> 470 molecules cDNA) from those with low (< or = 470 molecules) VEGF expression: 20 of the 26 basal cell carcinomas showed low VEGF expression, while 11 of the 13 squamous cell carcinomas showed high VEGFcDNA levels (p = 0.0003). Moreover, a significant association between a high microvessel density and high VEGFmRNA levels (p = 0.006) was found. Furthermore, when studying VEGF expression by immunohistochemistry, we obtained similar results and noted a correlation with VEGFmRNA expression (p < 0.0001). The association between high vascularization, high VEGF levels, and squamous cell histotype suggests the possible role of neoangiogenesis in determining the more aggressive biological behaviour of this type of cancer.     

High microvessel density in pancreatic ductal adenocarcinoma is associated with high grade

The objectives of this work are to study angiogenesis in pancreatic ductal adenocarcinoma using computerized morphometric and image analysis and to compare the microvascular density in intratumoral and peritumoral areas and normal pancreatic tissue. Microvascular density was analyzed in 60 cases of pancreatic ductal adenocarcinoma and 30 samples of normal pancreatic tissue using an avidin–biotin immunoperoxidase technique with an anti-CD31 antibody. Microvascular density (MVD) was analyzed through digital microimaging and computerized analysis. The blood vessel density in the tumor was significantly higher than in peritumoral areas and in normal pancreatic tissue. Well differentiated pancreatic ductal adenocarcinomas contained higher MVD than poorly differentiated carcinomas. In pancreatic adenocarcinoma, MVD is higher than in peritumoral tissue or normal pancreatic tissue.     

Overexpression of Thrombospondin-1 Decreases Angiogenesis and Inhibits the Growth of Human Cutaneous Squamous Cell Carcinomas

The function of the endogenous angiogenesis inhibitor thrombospondin-1 (TSP-1) in epithelial tumor development has remained controversial. We studied the in vitro growth characteristics and the in vivo tumor xenograft growth of the human squamous cell carcinoma cell lines A431 and SCC-13, stably transfected to overexpress human TSP-1. Overexpression of TSP-1 inhibited tumor growth of A431 xenotransplants, and completely abolished tumor formation by SCC-13 cells. TSP-1 overexpressing A431 tumors were characterized by extensive areas of necrosis and by decreased tumor vessel number and size. The effects of TSP-1 on tumor cell growth were indirect since tumor cell proliferation rates in vivo and in vitro, anchorage-dependent and -independent growth in vitro, and susceptibility to induction of apoptosis by serum withdrawal were unchanged in TSP-1 overexpressing tumor cells. However, TSP-1 overexpression up-regulated the TSP-1 receptor CD36, leading to enhanced adhesion of A431 cells to TSP-1. These findings establish TSP-1 as a potent inhibitor of angiogenesis and tumor growth in carcinomas of the skin.     

卵巢上皮肿瘤血管内皮生长因子受体3和CD31表达与肿瘤转移的研究

目的:研究卵巢肿瘤组织血管内皮生长因子受体3(VEGFR-3)和CD 31的表达与新生淋巴管和血管的生成及肿瘤转移的关系。方法: 采用免疫组织化学及图像分析方法,检测29例卵巢上皮癌和19例良性肿瘤组织中VEGFR-3 和CD31的表达,计数VEGFR-3阳性淋巴管数 (MLC) 和微脉管密度(MVD)。结果: 卵巢上皮癌MLC和MVD显著高于良性肿瘤和正常组织(MLC, P＜0.05; MVD, P＜0.01)。有淋巴转移的卵巢上皮癌患者MLC和MVD显著高于无淋巴转移患者(P＜0.05)。卵巢上皮癌临床分期Ⅲ-Ⅳ期患者的MLC和MVD显著高于Ⅰ-Ⅱ期(MLC,P＜0.05;MVD,P＜0.01)。卵巢上皮癌MLC和MVD在不同的组织学类型和组织学分级无显著差异(P＞0.05)。结论: 卵巢上皮肿瘤组织VEGFR-3和CD31的表达水平与肿瘤的转移密切相关;MLC和MVD提示肿瘤组织有淋巴管和血管的生成,可作为判断肿瘤转移的生物学指标。     

Microvascular structural entropy: A novel approach to assess angiogenesis in pituitary tumors

Entropy, a measure of the degree of disorder in a system, has recently been used in different morphologic studies to quantify regularity. Our aims were (a) to study the structural organization of the microvascular bed in prolactin (PRL)-producing adenomas and carcinomas, the most vascularized of pituitary tumors, by assessing microvascular structural entropy (MSE), and (b) to determine whether the degree of disorder of the capillary bed correlates with tumor cell proliferation as estimated by MIB-1 labeling, microvessel density (MVD), the most widely used method of quantifying blood vessel formation, and various clinicopathologic parameters (gender, age, tumor size and invasiveness). The morphometric study demonstrated statistically significant differences in MIB-1 labeling, MVD, and MSE between PRL-producing adenomas and carcinomas. Unlike MIB-1 labeling index (PRL-producing adenomas 1.5±0.27; carcinomas 15.0±4.04) and MVD (PRL-producing adenomas 2.7±0.34; carcinomas 4.2±0.72), the MSE values were significantly higher in adenomas (171.5±25.37) than in carcinomas (67.9±17.45). These results indicate that PRL-producing carcinomas have a less chaotic distribution of vessels than benign adenomas. In contrast to a lack of correlation between, microvessel density and other morphometric parameters, a strong negative correlation was found between MSE and MIB-1 labeling index (r=0.511, p=0.003). It thus appears that regular, less chaotic microvascular geometry contributes to increased proliferative activity in PRL cell tumors. Analysis of MSE may provide an independent parameter of tumor behavior, and contributes to a better understanding of the role of microvasculature in pituitary tumor progression.