Flt-4在不同级别脑星形细胞瘤中的表达意义

目的：探讨不同组织病理分级的脑星形细胞瘤中血管内皮生长因子受体3（Flt-4又称VEGFR-3）的表达意义。 方法： 采用免疫组织化学方法，检测50例不同级别脑星形细胞瘤患者手术切除标本中Flt-4、血管内皮生长因子（VEGF）的表达，并用抗FⅧ因子抗体标记瘤组织血管内皮细胞，计算肿瘤内微血管密度（IMVD）。 结果： Flt-4、VEGF总阳性表达率分别为52%（26/50）、60%（30/50）。Flt-4、VEGF均与脑星形细胞瘤病理分级呈显著正相关（等级相关系数分别为0.359、0.360,P＜0.05）。 结论： 脑星形细胞瘤中有Flt-4表达，主要表达于血管内皮细胞和部分肿瘤细胞，Flt-4既可是内皮细胞自分泌产生，部分还可来自瘤细胞的旁分泌；脑星形细胞瘤中Flt-4阳性表达的脉管是血管；Flt-4的表达与星形细胞瘤的病理分级相关     

神经系统多种肿瘤中组织型谷氨酰胺转氨酶蛋白的表达

目的 了解脑肿瘤中组织型谷氨酰胺转氨酶(tTG)蛋白的表达情况,探讨其与脑肿瘤类型和恶性程度的关系。方法采用免疫组织化学SP方法,检测tTG蛋白在62例星形细胞瘤、18例少突胶质细胞瘤、30例良性脑膜瘤、30例垂体腺瘤和10例正常脑组织中的表达。结果(1)脑肿瘤组织中tTG表达呈组织异质性,主要定位于血管内皮细胞、部分血管基底膜和部分肿瘤细胞胞质;(2)随着星形细胞瘤分化程度的降低,肿瘤细胞内tTG蛋白表达明显增加;(3)胶质瘤细胞内tTG蛋白表达强度明显高于良性脑膜瘤和垂体腺瘤;(4)在胶质母细胞瘤中,坏死和凋亡组织周围的肿瘤细胞tTG蛋白呈强阳性表达。结论脑肿瘤细胞内tTG蛋白表达与肿瘤的组织类型来源和恶性程度有关,可能促进星形细胞瘤恶性进展。     

水通道蛋白1、5在星形细胞瘤中的表达变化

目的:观察水通道蛋白1、5(AQP1、5)在人不同病理级别星形细胞瘤组织中的表达差异,探讨星形细胞瘤增殖、生长的分子机制.方法:收集人各个病理级别星形细胞瘤标本55例,以肿瘤周围相对正常脑组织作为对照,采用H-E染色诊断分级,石蜡切片免疫组织化学、免疫印迹分析及逆转录聚合酶链式反应观察AQP1、5及其mRNA的表达变化.结果:与正常脑组织相比,人星形胶质瘤组织中AQP1及其mRNA表达上调,随着星形细胞瘤病理级别的升高,AQP1及其mRNA表达增强,胶质母细胞瘤组织表达最强烈;而AQP5及其mRNA仅在高恶性星形细胞瘤组织中表达增强.结论:AQP1在人星形细胞瘤组织中表达与其病理级别相关,而AQP5仅在人高恶性星形细胞瘤组织中表达增强,提示不同病理级别胶质瘤组织中AQP的表达规律不尽相同.     

水通道蛋白4和人星形胶质细胞瘤在体内增殖和瘤周水肿的相关性研究

目的：研究水通道蛋白4（aquaporin-4, AQP4）和人星形胶质细胞瘤在体内增殖和瘤周水肿的相关性。方法建立人星形胶质细胞瘤裸鼠模型; EdU法检测细胞增殖;免疫组织化学法检测肿瘤组织内CD34阳性细胞表达,检测肿瘤组织微血管密度;免疫印迹法测AQP4蛋白表达;以人脑正常星形胶质细胞为阴性对照。结果细胞皮下注射一周后可见肿瘤长出, EdU法检测肿瘤增殖能力随肿瘤恶性程度增加而增大,免疫组织化学检测提示高度恶性组较低度恶性组具备更高的微血管密度, AQP4蛋白表达随恶性程度增加而增加。结论水通道蛋白4的表达水平和人星形细胞瘤增殖和瘤周水肿程度密切相关。     

人脑胶质瘤血管内皮细胞生长因子受体表达的研究

目的研究人脑胶质瘤血管内皮细胞生长因子受体(Vascular endot helial growth factor receptors, VEGFR)的表达及意义.方法应用免疫组织化学技术,检测52例手术切除的脑胶质细胞瘤组织中两种VEGFR(flt-1和fl k-1)的表达.结果①胶质细胞瘤组织中有flt-1和flk-1的表达 , 主要表达于肿瘤血管内皮细胞, 同时巨噬细胞的胞浆中也有表达;② 3组胶质细胞瘤中,VEGFR的表达率分别为16.0%、58.8%、90.0%,3组间有差异(p<0.05 );③脑胶质细胞瘤中, flt-1的表达与flk-1 的表达相关(R=0.993,p<0.01).结论正常脑组织中无VEGFR表达,脑胶质细胞瘤中有VEGFR表达,主要表达于血管内皮细胞中,VEGF通过旁分泌途径刺激脑胶质细胞瘤的血管发生; VEGF的促血管发生作用既可通过血管内皮细胞的VEGFR直接产生,又可通过促进巨噬细胞的局灶浸润间接产生;VEGFR表达与脑胶质瘤恶性程度呈正相关.     

牛bFGF-pcDNA3在人脐静脉内皮细胞中的表达及鉴定

目的:研究牛bFGF-pcDNA₃在体外培养人脐静脉内皮细胞中的表达与活性,及对该细胞生物学特性的影响。方法:脂质体法将bFGF-pcDNA₃真核表达载体转染体外培养的人脐静脉内皮细胞,经G418筛选阳性克隆。通过免疫细胞化学法检测bFGF的表达部位及Ⅷ因子相关抗原的表达。应用化学发光Westernblotting法检测bFGF在转染细胞与未转染细胞中的表达。绘制细胞的生长曲线并计算倍增时间,采用MTT法对bFGF的生物活性进行估计。结果:bFGF-pcDNA₃转染人脐静脉内皮细胞后,细胞呈梭形者增多。免疫细胞化学证实转染前后细胞均为血管内皮来源细胞,转染与未转染细胞均在胞浆内表达bFGF。Westernblotting证实细胞转染前后均表达17kDbFGF,但转染后表达量增高,细胞生长曲线上移,倍增时间缩短。MTT法证实转染细胞产生的bFGF其生物学活性约相当于持续添加外源性bFGF5714ng/L。结论:转染bFGFcDNA的人脐静脉内皮细胞能在体外增殖,并具有表达与分泌活性bFGF的功能。bFGF-pcDNA₃可引起内源性bFGF表达增高,对血管内皮细胞产生相应的生物学活性。     

人脑胶质瘤血管内皮细胞生长因子受体表达的研究

目的　研究人脑胶质瘤血管内皮细胞生长因子受体 (Vascularendothelialgrowthfactorreceptors,VEGFR)的表达及意义 .方法　应用免疫组织化学技术 ,检测 5 2例手术切除的脑胶质细胞瘤组织中两种VEGFR(flt- 1和flk - 1)的表达 .结果　①胶质细胞瘤组织中有flt- 1和flk- 1的表达 ,主要表达于肿瘤血管内皮细胞 ,同时巨噬细胞的胞浆中也有表达 ;② 3组胶质细胞瘤中 ,VEGFR的表达率分别为 16 .0 %、5 8.8%、90 .0 % ,3组间有差异 (p <0 .0 5 ) ;③脑胶质细胞瘤中 ,flt- 1的表达与flk - 1的表达相关 (R =0 .993,p<0 .0 1) .结论　正常脑组织中无VEGFR表达 ,脑胶质细胞瘤中有VEGFR表达 ,主要表达于血管内皮细胞中 ,VEGF通过旁分泌途径刺激脑胶质细胞瘤的血管发生 ;VEGF的促血管发生作用既可通过血管内皮细胞的VEGFR直接产生 ,又可通过促进巨噬细胞的局灶浸润间接产生 ;VEGFR表达与脑胶质瘤恶性程度呈正相关     

MCP-1/CCR2信号途径介导酒精诱导的乳腺癌血管新生

目的:研究单核细胞趋化蛋白1(MCP-1)及其受体CC趋化因子受体2(CCR2)在酒精刺激乳腺癌血管生成中的作用及其机制。方法:建立小鼠饮酒乳腺癌移植瘤模型,免疫组化检测肿瘤组织中MCP-1和CCR2表达与血管标志物血小板内皮细胞黏附分子1(PECAM-1)和血管内皮生长因子(VEGF)表达的相关性。体外建立3D肿瘤-内皮细胞共培养系统观察肿瘤血管新生,检测MCP-1/CCR2信号在酒精介导血管生成中的作用。通过细胞迁移实验检测MCP-1/CCR2是否增加细胞移动而促进脉管形成。结果:饮酒的荷瘤小鼠肿瘤组织中MCP-1和CCR2均高表达,且表达水平和血管新生标志物PECAM-1和VEGF相一致。通过3D肿瘤-内皮细胞共培养系统观察到小鼠乳腺癌E0771细胞和内皮细胞相互作用可促进血管的形成,酒精可以增强此种肿瘤血管新生效应。外源性MCP-1可以促进此种肿瘤血管生成,其受体CCR2抑制剂处理则可以有效抑制酒精刺激的肿瘤血管生成。进一步研究发现MCP-1/CCR2可以增强内皮细胞的迁移能力。结论:MCP-1/CCR2信号途径在酒精刺激乳腺癌血管生成中发挥重要作用,其机制可能是促进了内皮细胞...     

骨髓间充质干细胞在肿瘤血管生成过程中的作用

目的 研究人骨髓间充质干细胞(hMSC)在肿瘤血管生成过程中的作用.方法 通过梯度密度离心法及贴壁筛选法分离、培养hMSC;利用pLEGFP-N1逆转录病毒载体获得增强型绿色荧光蛋白(EGFP)标记的hMSC(hMSC-EGFP);流式细胞仪检测hMSC-EGFP的免疫表型及分化能力;通过建立BALB/C裸鼠实体瘤模型(分别皮下接种乳腺癌细胞系MCF-7及hMSC-EGFP细胞与MCF-7混悬液)来观察hMSC在肿瘤血管生成过程中的作用;检测肿瘤细胞和内皮细胞条件培养基对hMSC细胞生长和迁移的影响;体外诱导hMSC向内皮细胞分化,观察其对人脐静脉内皮细胞(HUVEC)迁移的影响.结果 hMSC-EGFP与hMSC形态相似,均呈成纤维细胞样;二者具有相似的免疫表型,在条件基质作用下,均能被诱导分化为成骨细胞及脂肪细胞;hMSC能促进肿瘤血管生成,单纯接种MCF-7组肿瘤平均血管密度为5.33±1.42,混悬液组为13.67±1.53,差异有统计学意义(P<0.05);大部分血管是由hMSC植入体内引起的宿主源性血管新生,只有少数血管的内皮细胞是由hMSC植入体内分化而来的;肿瘤细胞和内皮细胞能够通过其旁分泌作用促进hMSC的生长和迁移;经内皮诱导2周后,hMSC呈CD31阳性;hMSC能促进HUVEC的迁移.结论 MSC具有促进肿瘤血管生成的作用.     

钠氢交换体1在星形细胞瘤中的表达及其与恶性程度的关系*

目的：检测人星形细胞瘤和正常脑组织中钠氢交换体1（ NHE1）的表达差异及其与恶性程度的关系,探 讨星形细胞瘤增殖、生长的分子机制。方法：收集人星形细胞瘤标本51 例,低、高级别星形细胞瘤组织分别为 22 例、29 例,以肿瘤周围相对正常脑组织作为对照。用H-E 染色进行诊断和分级,免疫组织化学和免疫印迹检 测肿瘤组织与正常脑组织中NHE1表达变化。结果：NHE1主要分布在对照组神经元和少量星形胶质细胞胞膜上; 在肿瘤组织中,NHE1分布在低级别星形细胞瘤细胞膜上,并强烈表达于高级别星形细胞瘤的胞质和胞膜上。与 对照组相比较,在低级别和高级别星形细胞瘤组织中NHE1表达上调,其中,恶性程度较高的高级别肿瘤相对于 恶性程度低的低级别肿瘤,NHE1的表达更为强烈。结论：NHE1在人星形细胞瘤组织中表达增强,其强度变化 与肿瘤的恶性程度有关。     

VEGF、bFGF、PCNA和P53在人脑星形胶质瘤的表达

目的探讨血管内皮生长因子(VEGF)、碱性成纤维细胞生长因子(bFGF)、增殖性细胞核抗原(PCNA)和抑癌基因蛋白(P53)在人脑星形胶质瘤中的表达。方法采用免疫组织化学(S-P)法,检测120例人脑胶质瘤标本中VEGF、bFGF、PCNA、P53的表达。结果在正常脑组织VEGF和PCNA无表达,bFGF和P53呈微量表达。Ⅰ~Ⅳ级人脑胶质瘤中VEGF、bFGF、PCNA、P53的阳性表达率随人脑胶质瘤病理分级的增加而增多,Ⅳ级>Ⅲ级>Ⅱ级>Ⅰ级(P<0.05)。结论VEGF、bFGF、PCNA、P53的过表达与人脑星形胶质瘤的恶性度呈正相关。     

A ribonuclease inhibitor expresses anti-angiogenic properties and leads to reduced tumor growth in mice.

Our experiments were designed to determine whether recombinant ribonuclease inhibitor (RNasin) could inhibit angiogenesis and reduce tumor growth in adult mice. We used the Fajardo disc angiogenesis assay as the primary means of measuring new blood vessel growth. This assay measures the penetration of cells into a polyvinyl alcohol sponge with a central core of ELVAX-coated sponge containing test substances. Cell penetration was reduced to 29.3% of control (phosphate-buffered saline; heat-inactivated RNasin) values. Endothelial cell influx was measured by lectin staining and confirmed by culturing cells isolated from sponges by collagenase treatment. RNasin also reduced the augmented reaction evoked by either basic fibroblast growth factor (bFGF) or sodium orthovanadate. To confirm the anti-angiogenic activity of RNasin, Hydron-coated polyvinyl sponges containing bFGF or bFGF plus RNasin were implanted into adult mouse corneas. bFGF induced a strong angiogenic response that was almost completely inhibited by RNasin. RNasin-containing ELVAX-coated sponges implanted subcutaneously underneath an intradermal inoculum of C755 mammary tumor cells caused significant reduction in tumor growth (P < 0.005). The antitumor effect of RNasin correlated with its effect on tumor-induced neovascularization, suggesting that the ability of RNasin to affect tumor growth was due to its ability to inhibit angiogenesis.     

Caveolin-1 knockout mice show an impaired angiogenic response to exogenous stimuli

Recent studies have shown that caveolin-1 (Cav-1) plays an important role as a regulator of angiogenesis in vitro. Here, we use Cav-1 knockout (KO) mice as a model system to examine the in vivo relevance of these findings. A primary mediator of angiogenesis is basic fibroblast growth factor (bFGF). Thus, we studied bFGF-induced angiogenesis in Cav-1 KO mice using a reconstituted basement membrane system, ie, Matrigel plugs, supplemented with bFGF. In Cav-1 KO mice, implanted Matrigel plugs showed a dramatic reduction in both vessel infiltration and density, as compared with identical plugs implanted in wild-type control mice. We also examined the necessity of Cav-1 to support the angiogenic response of an exogenous tumor by subcutaneously injecting Cav-1 KO mice with the melanoma cell line, B16-F10. We show that tumor weight, volume, and vessel density are all reduced in Cav-1 KO mice, consistent with diminished angiogenesis. Ultrastructural analysis of newly formed capillaries within the exogenous tumors reveals a lack of endothelial caveolae and incomplete capillary formation in Cav-1 KO mice. These results provide novel evidence that Cav-1 and caveolae play an important positive role in the process of pathological angiogenesis in vivo.     

脑星形细胞瘤中bFGF及其受体对血管新生和肿瘤细胞增殖的影响

目的：为探讨碱性纤维母细胞生长因子（ｂＦＧＦ）及其受体（ＦＧＦＲ－２）对人星形细胞瘤的血管新生及细胞增殖的作用。方法：彩和免疫组织化学方法,结果：发现ｂＦＧＦ及其受体,增殖细胞核抗原（ＰＣＮＡ）在瘤细胞及血管内皮细胞中均有表达,高级别星形细胞瘤的表达阳性率高于低级别者,ｂＦＧＦ在瘤细胞中的表达阳性率分别为与ＦＧＦＲ－２及ＰＣＮＡ的表达阳性率呈正相关关系（Ｐ〈０．０１,Ｐ〈０．０５）,ｂＦＧＦ及其受     

人肺癌细胞LALU血管生成过程的形态学观察及意义

目的：观察人肺癌细胞血管生成过程的病理形态学、超微结构特点及意义。方法：采用人肺癌细胞LALU皮下移植瘤模型,以病理动态形态学及透射电镜不同时期肿瘤血管生成状态。结果：光镜显示,人肺癌移植瘤第2天至第10天之间可分为血管生成前期和血管形成期,在肿瘤血管生成的第20天出现肺转移灶。电镜显示,人肺癌移植瘤第2天出现成血管细胞,第4－10天,不成熟血管内皮细胞逐渐形成务管腔伴有较完整的新生基底板,内皮细胞趋向成熟发展,第20天肿瘤血管内皮细胞更成熟,部分区域新生毛细血管基底板发育不全或缺陷。在以上全过程中癌细胞突起直接与成血管细胞、血管内皮细胞及血管壁相连。结论：人肺癌细胞可诱导自身肿瘤血管生成,病理形态学及电镜有其特征性形态学改变,且与转移密切相关,为肺癌的血管导向治疗提供了重要依据。     

Computational analysis of tumor angiogenesis patterns using a two-dimensional model

Tumor angiogenesis was simulated using a two-dimensional computational model. The equation that governed angiogenesis comprised a tumor angiogenesis factor (TAF) conservation equation in time and space, which was solved numerically using the Galerkin finite element method. The time derivative in the equation was approximated by a forward Euler scheme. A stochastic process model was used to simulate vessel formation and vessel elongation towards a paracrine site, i.e., tumor-secreted basic fibroblast growth factor (bFGF). In this study, we assumed a two-dimensional model that represented a thin (1.0 mm) slice of the tumor. The growth of the tumor over time was modeled according to the dynamic value of bFGF secreted within the tumor. The data used for the model were based on a previously reported model of a brain tumor in which four distinct stages (multicellular spherical, first detectable lesion, diagnosis, and death of the virtual patient) were modeled. In our study, computation was not continued beyond the 'diagnosis' time point to avoid the computational complexity of analyzing numerous vascular branches. The numerical solutions revealed that no bFGF remained within the region in which vessels developed, owing to the uptake of bFGF by endothelial cells. Consequently, a sharp declining gradient of bFGF existed near the surface of the tumor. The vascular architecture developed numerous branches close to the tumor surface (the brush-border effect). Asymmetrical tumor growth was associated with a greater degree of branching at the tumor surface.     

Expression of bFGF and VEGF in brain astrocytoma.

Neovascularization is an important factor in the prognosis of brain tumor and many angiogenetic factors have been evaluated for prognostic significance. Among them, basic fibroblast growth factor (bFGF) and vascular endothelial growth factor (VEGF) are known as potent angiogentic factors and mitogens. We evaluated seven cases of grade II brain astrocytoma. Four, group A, was diagnosed as anaplastic progression at their second operation, and three, group B, did not. Using monoclonal antibodies to bFGF and VEGF in paraffin embedded tissue from first operation, their immunoreactivity and differences between two groups were examined. The growth fractions of these tumor were also measured by Ki-67 monoclonal antibodies (MIB1). Immunostaining for bFGF in tumor cells were observed in both nuclei and cytoplasm, and for VEGF, mainly observed in the cytoplasm. Mean cell count number +/- standard deviation per high power field in each were as follows: 1) for bFGF, 20.08 +/- 6.38 in group A and 0.87 +/- 0.90 in group B (P < 0.01), 2) for VEGF, 43.75 +/- 17.09 in group A, and 0.8 +/- 1.06 in group B (P < 0.05) and 3) for the proliferation index with Ki-67 antibodies, 3.20 +/- 0.81 in group A and 0.77 +/- 1.03 in group B (P < 0.05). This data supports the assertion that angiogenetic factor such as bFGF and VEGF may contribute to progressive change of astrocytoma by tumor angiogenesis.     

表达Tie2基因的单核细胞研究进展

肿瘤血管的生成和发展在肿瘤的生长和恶化过程中起着关键作用。一类表达Tie2基因的单核细胞（TEM）通过一些生长因子和化学信号被募集到肿瘤组织中,旁分泌细胞因子促进肿瘤血管的生成和发展。TEM在促进肿瘤血管形成中起着重要作用,与血管内皮细胞祖细胞（EPC）不同的是,TEM只是在肿瘤的血管生成中起促进作用,但在肿瘤周围临近的正常组织中没有发现其存在,TEM被认为是一类肿瘤组织特异性的细胞。以TEM为载体细胞,通过TEM表达抗肿瘤药物,靶向递送的抗肿瘤药物能够有效的抑制肿瘤的生长和恶化。     

骨髓间充质干细胞向血管内皮细胞分化过程在银屑病发病中的作用

目的:将银屑病患者骨髓间充质干细胞(BMMSCs)体外分化为血管内皮细胞(VEC),并对定向分化的VEC活性进行初步研究,为银屑病患者BMMSCs生物特性的深入研究提供依据。方法:寻常型银屑病患者20例,健康对照组15例为骨髓象正常者。采用密度梯度离心法分离骨髓单个核细胞,通过贴壁法培养BMMSCs,流式细胞仪鉴定细胞表面标志;加入血管内皮细胞生长因子(VEGF)、碱性成纤维细胞生长因子(bFGF)定向诱导BMMSCs向VEC分化,流式细胞仪进行细胞表型鉴定;免疫细胞荧光技术鉴定VEC标志物VWF的表达;体外血管成形试验检测诱导的内皮细胞体外成形能力。结果:流式测定显示两组培养的BMMSCs高表达CD44、CD29,而HLA-DR、CD45、CD34阴性表达;银屑病组CD34、CD45、ICAM-1、HLA-DR阳性表达,且明显高于对照组(P﹤0.05);免疫细胞化学显示两组都可分化为VEC,与正常对照组比较具有统计学差异(P﹤0.05),银屑病患者诱导的VEC体外血管成形能力较强。结论:银屑病患者BMMSCs生物学活性异常,且易于转分化为VEC。银屑病患者BMMSCs-VEC发育分化系统在银屑病患者皮损真皮乳头层微血管异常增生过程中可能发挥重要的作用。     

Tie2-expressing monocytes: regulation of tumor angiogenesis and therapeutic implications

Tumor-infiltrating myeloid cells are involved in crucial processes during tumor development. A subset of monocytes that express the angiopoietin receptor Tie2 play an important role in tumor angiogenesis. Selective depletion of these Tie2-expressing monocytes (TEMs) in tumor-bearing mice inhibits tumor angiogenesis and growth, suggesting that they might regulate angiogenic processes in tumors by providing paracrine support to nascent blood vessels. TEMs have also been identified in human blood and tumors. We discuss here the therapeutic opportunities emanating from the discovery of TEMs, which include the identification of new antitumor targets, monitoring TEMs as surrogate markers for clinical responses in cancer patients, and the possible use of TEMs as cellular vehicles for gene delivery to tumors.