Basic fibroblast growth factor and the complexity of tumour angiogenesis

Intrinsic biochemical properties of basic fibroblast growth factor (bFGF) do not adequately explain its potent pro-angiogenic activity. In vivo, bFGF can act in concert with other modulators of angiogenesis, such as vascular endothelial growth factor (VEGF). It is suggested that due to the complexity of angiogenic growth factor networks the process may be regulated in a non-linear fashion.     

The effects of cadmium on VEGF-mediated angiogenesis in HUVECs

Cadmium (Cd) is a highly toxic element that causes morphologic alterations and dysfunction in blood vessels. The altered vascular function caused by cadmium has been implicated in a range of chronic diseases, including hypertension. The effects of cadmium are a multisystem phenomenon involving inflammation, hypertrophy, apoptosis, angiogenesis and important processes involved in vascular remodeling systems. Vascular endothelial growth factor (VEGF) plays a major role in cell growth and angiogenesis under pathologic conditions. VEGF secretion is related to anti-apoptosis protein expression and attenuates apoptosis in endothelial cells. This study examined the VEGF-dependent mechanisms of angiogenesis and apoptosis in cadmium-treated endothelial cells (HUVECs). The effects and mechanisms of cadmium in endothelial cells (HUVECs) were examined by exposing the cells to different doses of cadmium chloride (2.5-40 μ m). After the cadmium treatment, the angiogenesis and apoptosis mechanisms related to VEGF in cadmium-treated HUVECs were examined. As a result, the low concentration of cadmium increased the tube formation in HUVECs. In addition, cadmium at concentrations of 5 and 10 μ m increased VEGF secretion and VEGFR2 activity, which suggest that cadmium affects the growth of blood vessels. All three MAPK pathways, namely ERK, JNK and p38, were activated by cadmium in HUVECs. However, high concentrations of cadmium caused cell damage, disrupted tube formation and inhibited VEGF expression and the activities of VEGFR2 and MAPK in HUVECs. Cadmium has dual functions through VEGF-dependent mechanisms in a dose-dependent manner. In this study, the dual effects of cadmium might alter angiogenesis and induce apoptosis through VEGF pathways in HUVECs.     

培养基组分对蛹虫草生物量及核苷、碱基积累的影响

考察了碳源、氮源和金属离子对蛹虫草发酵生物量和7种核苷、碱基积累的影响，结果表明以20％土豆汁＋2％葡萄糖为碳源，0.3％酵母膏＋0.3％蛋白胨为氮源，并在培养基中加入0．1mmol／LMn^2＋能促进菌体生长和核苷、碱基的积累。在最佳条件下，腺苷和3＇-脱氧腺苷在菌丝体中含量分别为4．96、0．199mg／g，在气生菌丝体中分别为4．91、7．22mg／g。     

The potential of fibroblast growth factor/fibroblast growth factor receptor signaling as a therapeutic target in tumor angiogenesis

Introduction: Fibroblast growth factors (FGFs) are endowed with a potent pro-angiogenic activity. Activation of the FGF/FGF receptor (FGFR) system occurs in a variety of human tumors. This may lead to neovascularization, supporting tumor progression and metastatic dissemination. Thus, a compelling biologic rationale exists for the development of anti-FGF/FGFR agents for the inhibition of tumor angiogenesis in cancer therapy.

Areas covered: A comprehensive search on PubMed was performed to identify studies on the role of the FGF/FGFR system in angiogenesis. Endothelial FGFR signaling, the pro-angiogenic function of canonical FGFs, and their role in human tumors are described. In addition, experimental approaches aimed at the identification and characterization of nonselective and selective FGF/FGFR inhibitors and their evaluation in clinical trials are summarized.

Expert opinion: Different approaches can be envisaged to inhibit the FGF/FGFR system, a target for the development of ‘two-compartment’ anti-angiogenic/anti-tumor agents, including FGFR selective and nonselective small-molecule tyrosine kinase inhibitors, anti-FGFR antibodies, and FGF ligand traps. Further studies are required to define the correlation between tumor vascularization and activation of the FGF/FGFR system and for the identification of cancer patients more likely to benefit from anti-FGF/FGFR treatments. In addition, advantages and disadvantages about the use of selective versus non-selective FGF inhibitors remain to be elucidated.     

辛伐他汀对脐静脉内皮细胞金属基质蛋白酶9表达的影响

目的观察辛伐他汀对脐静脉内皮细胞（human umbilical vein endothelial cell,HUVEC）金属基质蛋白酶9（matrix metalloproteinase-9,MMP-9）表达的影响。方法采用逆转录聚合酶链反应及蛋白质免疫印迹分析检测MMP-9mRNA转录和蛋白水平表达,观察辛伐他汀不同浓度及不同孵育时间HUVECMMP-9表达的影响。结果辛伐他汀呈浓度和时间依赖性减低HU-VEC的MMP-9mRNA转录和蛋白水平的表达。结论辛伐他汀可抑制HUVE CMMP-9表达,防治动脉粥样硬化。     

In vitro inhibition of angiogenesis by hydroalcoholic extract of oak (Quercus infectoria) acorn shell via suppressing VEGF,MMP-2, and MMP-9 secretion

Context: Angiogenesis is an essential factor for cancer progression. Although more attention is paid in angiogenesis on its role in cancer biology, many other non-neoplastic diseases are also angiogenic-dependent. Recently, there is motivation to control cancer via inhibition of angiogenesis.

Objective: Quercus infectoria Olivier var (Fagaceae) (oak) is a plant whose different parts, such as its fruit shell, have been used extensively as a traditional drug in the west part of Iran. Although some biological properties of oak are determined, its effects on angiogenesis are unclear. So, we investigated the antiangiogenic effects of oak acorn shell.

Materials and methods: Fresh oak acorns were collected, and after authentication; hydroalcoholic extract of acorn shells (5, 10, 20, 30, 40, 60, 80, and 100 μg/ml) was used for evaluation of its cytotoxicity, antiproliferative, and antiangiogenic effects in vitro. Also, effects of the extract on vascular endothelial growth factor (VEGF), matrix metalloproteinase-2 (MMP-2) and MMP-9 secretion were assayed using enzyme-linked immunosorbent assay (ELISA) and gelatin zymography. Results: Treatment with hydroalcoholic extract in eight doses resulted in a significant decrease of endothelial cell proliferation and angiogenesis with an IC₅₀ value of ~20 μg/ml, without any toxic effect. At 40 μg/ml, the extract inhibited MMP-9 activity; however, a dose-dependent reduction (60–80 µg/ml) in MMP-2 activity was seen. VEGF secretion was decreased with increase in the concentration of the extract from 5 to 100 μg/ml.

Discussion and conclusion: This study indicated that hydroalcoholic extract of oak acorn shell acts as a potent antiangiogenic agent which exerts its inhibitory effect mainly through downregulation of essential mediators such as VEGF and MMPs.     

N-benzyl-5-phenyl-1H-pyrazole-3-carboxamide promotes vascular endothelial cell angiogenesis and migration in the absence of serum and FGF-2

Aim:

To investigate the effect of N-benzyl-5-phenyl-1H-pyrazole-3-carboxamide (BPC) on angiogenesis in human umbilical vein endothelial cells (HUVECs).

Methods:

Capillary-like tube formation on matrigel and cell migration analyses were performed in the absence of serum and fibroblast growth factor (FGF-2). Reactive oxygen species (ROS) were measured using a fluorescent probe, 2′, 7′- dichlorodihydrofluorescein (DCHF). The nitric oxide (NO) production of HUVECs was examined using a NO detection kit. Morphological observation under a phase contrast microscope, a viability assay using 3-[4, 5-dimethylthiazol-2-yl]-2, 5-diphenyl-tetrazolium (MTT) and a lactate dehydrogenase (LDH) activity analysis by a detection kit were performed to evaluate the toxicity of BPC on HUVECs in the presence of serum and FGF-2. The level of hypoxia-inducible factor 1α (HIF-1α) and the release of vascular endothelial growth factor (VEGF) were measured by Western blot and ELISA, respectively.

Results:

In the absence of serum and FGF-2, cells treated with BPC (5-20 μmol/L) rapidly aligned with one another and formed tube-like structures within 12 h. In the presence of serum and FGF-2, cells treated with BPC for 24, 48 and 72 h had no changes in morphology, viability or LDH release compared with the control group. Cell migration in the BPC-treated group was significantly increased compared with the control group. During this process, NO production and ROS level were elevated dramatically, and the levels of HIF-1α and VEGF were increased dependent on the generation of ROS.

Conclusion:

BPC most effectively promoted angiogenesis and migration in HUVECs in the absence of FGF-2 and serum.     

Arsenite suppresses angiogenesis of vascular endothelial cells mediated by Platelet Derived Growth Factor Receptor-beta

The present study aimed to investigate the effects of sodium arsenite (NaAsO₂) on the angiogenesis of human umbilical vein endothelial cells (HUVECs) and the mechanism involved. Firstly, a Matrigel-based in vitro angiogenesis assay demonstrated that arsenite suppressed the angiogenesis of HUVECs in a dose-dependent manner. Then by using a global inhibitor for multiple growth factor receptors (E7080) and a specific inhibitor of PDGFR-beta (CP-673451), we found that E7080 completely prevented and CP-673451 significantly decreased the angiogenesis of HUVECs. This suggested that angiogenesis of HUVECs depends on the signal pathway mediated by tyrosine kinase receptors and that among them, PDGFR-beta has an important regulatory function. Finally by using porcine aortic endothelial cells which stably express human PDGFR-beta, we found that arsenite suppressed the angiogenesis mediated by PDGFR-beta. Based on these results, we conclude that arsenite suppressed the angiogenesis of the vascular endothelial cells, that this effect is mediated by PDGFR-beta, and postulate that it might contribute to the injuries of blood vessel in arsenism.     

环磷腺苷葡胺对人脐静脉血管内皮细胞增殖、迁移、管腔形成及凋亡的影响

目的 探索环磷腺苷葡胺（meglumine cyclic adenylate,MCA）对人脐静脉血管内皮细胞（human umbilical vein endothelial cells,HUVEC）增殖、迁移、管腔形成及凋亡的影响。方法 通过显微镜观察、MTT法、划痕修复试验、管腔形成试验、Western blotting观察不同浓度MCA对HUVEC细胞形态、增殖、迁移、管腔形成能力及凋亡相关蛋白表达的影响。结果 显微镜观察发现,随着MCA剂量增加,HUVEC细胞形态由多角形变为卵圆形。MCA可呈浓度依赖地抑制HUVEC增殖、迁移、管腔形成,并且高剂量的MCA还可诱导细胞凋亡,表现为细胞凋亡数目增加,Bax、Cleaved-PARP蛋白表达上调,PARP、Bcl-2蛋白表达下调。结论 MCA可抑制HUVEC细胞增殖、迁移、管腔形成,并诱导细胞凋亡。     

Recent developments in the inhibition of angiogenesis: examples from studies on platelet factor-4 and the VEGF/VEGFR system

Inhibition of angiogenesis is an important strategy to block tumor growth and invasion. We discuss herein results from our ongoing investigations on platelet factor-4 (PF-4) and the VEGF/VEGFR system. Platelet factor-4 (PF-4) is an anti-angiogenic ELR-negative chemokine. PF-4 inhibits endothelial cell proliferation and migration, and angiogenesis in vitro and in vivo. We have studied the structure and anti-angiogenic activities of a C-terminal fragment of PF-4 named PF-4 CTF. This molecule retains anti-angiogenic activity, blocks the interaction of angiogenesis factors with their receptors and may also be improved by mutation or domain-swapping. It seems, therefore, to be a good candidate for further development. Furthermore, we have developed a cyclic vascular endothelial growth inhibitor (Cyclo VEGI) from the structure of VEGF-A. In aqueous solution, cyclo-VEGI adopts an alpha helix conformation. Cyclo-VEGI inhibits binding of iodinated VEGF(165) to endothelial cells and angiogenesis. Furthermore, cyclo-VEGI significantly blocks the growth of established intracranial glioma in nude and syngeneic mice and improves survival.     

普纳替尼对人血管内皮细胞功能的影响

目的 观察普纳替尼(Ponatinib)对人血管内皮细胞的增殖、迁移、血管形成及NO合成释放的影响, 从细胞水平评价Ponatinib血栓不良反应形成机制。方法 采用CCK-8法、体外划痕法、Matrigel基底膜成管法及NO检测试剂盒分别考察Ponatinib对人脐静脉内皮细胞(HUVECs)的细胞毒作用、迁移能力、血管形成能力及细胞NO释放水平的影响。结果 研究表明Ponatinib对HUVECs细胞半数抑制浓度(IC₅₀)为(0.69±0.05)μmol/L。非毒性剂量的Ponatinib能够不同程度抑制HUVECs细胞的迁移、血管形成及NO的释放(P<0.05)。结论 Ponatinib通过影响人血管内皮细胞增殖、迁移、血管形成等正常功能而造成血管内皮损伤, 可能为其诱发血栓的原因之一。     

多毛孢菌菌粉抑制庆大霉素诱导的猪肾小管上皮细胞凋亡及纤维化生长因子的表达

目的：研究人工培养的多毛孢菌菌粉水提物对庆大霉素诱导的近端肾小管上皮细胞损伤、凋亡的保护作用及对碱性纤维化生长因子(basic fibro-blast growth factor，bFGF)mRNA表达的影响。方法：将猪近端肾小管上皮细胞株(LLCPK)复苏培养，分成正常对照组、庆大霉素组和多毛孢菌组，除对照组外，用庆大霉素刺激，多毛孢菌组同时加多毛孢菌菌粉水提物干预。以MTT法观测存活细胞数；并测定细胞上清液N-乙酰-β-D-氨基糖苷酶(NAG)浓度；荧光标记细胞表面Annexin V，以细胞流式法测定其表达；RT-PCR检测细胞碱性纤维化生长因子mRNA的表达。结果与结论：庆大霉素可引起细胞存活率的显降低，N-乙酰-β-D-氨基糖苷酶浓度显增高；并提高细胞Annexin V的表达，即诱导白细胞调亡，和诱导LLCPK细胞bFGF mRNA的表达。多毛孢菌菌粉水提物能提高肾小管上皮细胞LLCPK存活率，降低细胞调亡数，并显抑制bFGF mRNA的表达。     

微RNA-24对过氧化氢诱导的人脐静脉血管内皮细胞凋亡的影响及作用机制

目的探讨微RNA-24(miR-24)对H2O2诱导的人脐静脉血管内皮细胞(HUVEC)存活、迁移和凋亡的影响及作用机制。方法通过转染miR-24高表达、miR-24抑制物(anti-miR-24)及其阴性对照慢病毒质粒(miR-24 NC)构建稳转细胞,3种细胞用H2O2500μmol·L^-1处理12 h。采用四甲基偶氮唑盐(MTT)法检测细胞存活率,划痕实验检测细胞迁移率,Hoechst33258染色及流式细胞术检测细胞凋亡,实时荧光定量聚合酶链反应(qRT-PCR)检测miR-24,Bax,Bcl-2和胱天蛋白酶3 mRNA表达水平,Western印迹法和免疫细胞化学法检测Bax、Bcl-2和胱天蛋白酶3蛋白表达水平。结果与miR-24 NC组比,miR-24高表达组miR-24表达升高(P<0.05),而anti-miR-24组降低(P<0.05)。与正常对照组比,H2O2组细胞凋亡率增加(P<0.05)、细胞存活和迁移率降低(P<0.05),表明氧化损伤模型构建成功。与H2O2+miR-24 NC组比,H2O2+miR-24高表达组上述指标较H2O2+miR-24 NC组升高(P<0.05),促凋亡蛋白Bax和胱天蛋白酶3 mRNA与蛋白表达量增加,抑凋亡蛋白Bcl-2 mRNA和蛋白表达量降低(P<0.05),而H2O2+anti-miR-24组可降低细胞凋亡率、增加细胞存活和迁移率,降低Bax和胱天蛋白酶3 mRNA与蛋白表达水平,增加Bcl-2 mRNA和蛋白表达水平(P<0.05)。结论氧化应激状态下,miR-24可通过上调Bax、胱天蛋白3表达和下调Bcl-2蛋白表达,促进HUVEC凋亡和抑制其存活和迁移能力。     

阿司匹林对S180肿瘤生长及血管生长相关因子表达的抑制作用

目的　从抗血管生成的角度研究阿司匹林(Asp)预防和治疗肿瘤的机理。方法　昆明种小鼠随机分为对照组 ,替加氟组 ,Asp 5 0 ,2 5 ,10mg·kg- 1组 ,于接种S180肿瘤细胞后d 2开始ig给药 ,连续9d ,观察抑瘤率。采用免疫组化的方法研究Asp对肿瘤组织环氧合酶 2 (COX 2 )及血管相关生长因子的作用。结果　Asp 3个剂量组均有一定的抑瘤作用 ,大剂量抑瘤率为 2 1.1%。免疫组化染色显示Asp对肿瘤组织的COX 2表达有明显的抑制作用 ,同时血管生长相关因子血管内皮生长因子、纤维细胞生长因子 2表达也明显下调 ,肿瘤组织微血管密度明显降低。结论　Asp对S180肿瘤有抑制作用 ,它可以抑制与血管生长相关的COX 2的表达而抑制肿瘤血管的生长 ,进而抑制肿瘤的生长。抑制肿瘤血管的生长可能是Asp预防和治疗肿瘤的机理之一。     

益气养阴方对鸡胚尿囊膜移植瘤组织血管内皮生长因子表达的影响

目的：研究益气养阴方抗肿瘤诱导鸡胚尿囊膜（cAM）血管生成及对CAM移植瘤细胞血管内皮生长因子（VEGF）表达的效应。方法：制备接种肿瘤细胞的CAM模型,采用血清药理学方法制备含药血清。观察含药血清对肿瘤细胞诱导CAM血管生成的影响,并与生理盐水血清组对照。另外应用免疫组织化学及其组织形态学定量分析方法对VEGF在CAM移植瘤中的表达进行研究。结果：益气养阴方含药血清可抑制肿瘤细胞诱导CAM血管生成。益气养阴方组VEGF的表达均明显低于对照组,差异有统计学意义（P〈0．05）。结论：益气养阴方对肿瘤诱导的CAM血管生成有明显抑制作用,降低VEGF的表达可能是其抑制肿瘤血管生成的主要机制之一。     

非诺贝特对溶血卵磷脂诱导的血管内皮细胞增生及凋亡的影响

目的:观察非诺贝特对溶血卵磷脂(LPC)诱导的血管内皮细胞增生、凋亡的影响并探讨其机制。方法:体外培养人脐静脉内皮细胞(HUVECs),分为正常对照组、LPC组、非诺贝特低浓度组(10μmol·L-1)、非诺贝特中浓度组(50μmol·L-1)及非诺贝特高浓度组(100μmol·L-1)。分别观测LPC对血管内皮细胞增生、凋亡及凋亡调控蛋白抑制X连锁凋亡抑制蛋白(XIAP)的影响,及非诺贝特干预后的变化。结果:与正常对照组比较,LPC抑制内皮细胞增生,促进内皮细胞凋亡,XIAP表达减弱。非诺贝特可干预LPC对内皮细胞的作用,使内皮细胞增生增强,凋亡减少,XIAP表达增强。结论:非诺贝特可通过促进XIAP表达干预LPC对HUVECs增生及凋亡的影响。     

新藤黄酸干预肺腺癌血管生成的细胞学研究

目的 通过对人脐静脉内皮细胞HUVEC和人肺腺癌A549的培养,检测含新藤黄酸(GNA)条件培养基对血管内皮细胞存活率、成管和生长的影响.方法 采用甲基噻唑基四唑(MTT)法和平板克隆实验法研究GNA对HUVEC存活率和克隆形成率的影响;应用薄层胶原建立血管内皮细胞的二维培养模型,观察GN A对于血管内皮细胞成管现象的影响;采用细胞划痕愈合和小室迁移实验考察GNA对HUVEC的迁移能力影响;Westernblot检测血管内皮生长因子(VEGF)和缺氧诱导因子(HIF-1α)蛋白的表达.结果 MTT检测结果显示,HUVEC细胞存活率和克隆形成率随GNA剂量增加而降低.GNA可抑制HUVEC细胞的迁移.还可抑制HUVEC管腔样结构形成.此外,GNA可下调HUVEC中VEGF和HIF-1α蛋白的表达.结论GNA可在体外抑制血管生成,其作用机制可能与抑制肿瘤细胞分泌的HIF-1α和VEGF有关.     

布地奈德对哮喘大鼠碱性成纤维细胞生长因子蛋白和mRNA表达的影响

目的：观察碱性成纤维细胞生长因子在急性哮喘大鼠肺组织的表达情况及布地奈德的干预影响.方法：36只雄性SD大鼠随机分为对照组、哮喘组和布地纳德治疗组,以卵清白蛋白激发法制备哮喘模型,采用ELISA法测定支气管肺泡灌洗液中碱性成纤维细胞生长因子的含量,免疫组化和原位杂交法测定肺组织中碱性成纤维细胞生长因子蛋白和mRNA的表达情况.结果：支气管肺泡灌洗液中的碱性成纤维细胞生长因子浓度、肺组织碱性成纤维细胞生长因子蛋白和mRNA的表达水平哮喘组显著高于对照组（P＜0.01）,治疗组显著低于哮喘组（P＜0.01）,但与对照组相比仍较高（P＜0.01）,上皮细胞为主要表达细胞.结论：碱性成纤维细胞生长因子参与了哮喘的发病机制,布地奈德可抑制哮喘急性期碱性成纤维细胞生长因子蛋白和mRNA的表达增加效应,这可能是布地奈德抑制哮喘气道重塑的重要机制之一.     

Effect of an oversulfated exopolysaccharide on angiogenesis induced by fibroblast growth factor-2 or vascular endothelial growth factor in vitro

The aim of this study was to determine the angiogenic properties of an oversulfated exopolysaccharide (OS-EPS) derived from a polysaccharide secreted by the mesophilic bacterium Alteromonas infernus. We compared the effect of this OS-EPS with that of a non-oversulfated exopolysaccharide (EPS) on human umbilical vein endothelial cell (HUVEC) proliferation, migration and differentiation induced by basic fibroblast growth factor (FGF-2) or vascular endothelial growth factor (VEGF). OS-EPS enhanced HUVEC proliferation by 58% when used alone, and by respectively 30% and 70% in the presence of FGF-2 and VEGF. OS-EPS also increased the density of tubular structures on Matrigel in the presence of FGF-2 or VEGF. Vascular tube formation was related to alpha(6) integrin subunit expression, which was enhanced by 50% in the presence of the growth factors. Indeed, a monoclonal anti-alpha(6) blocking antibody abolished this vascular tube formation. EPS had no effect in any of the experimental conditions, underlying the importance of sulfation in the angiogenic effects of exopolysaccharide. By potentiating the angiogenic activity of FGF-2 and/or VEGF, OS-EPS, which possesses low anticoagulant activity and thus a low hemorrhagic risk, could potentially be used to accelerate vascular wound healing or to promote the growth of collateral blood vessels in ischemic tissues.     

山慈菇提取液对乳腺癌大鼠肿瘤组织血管内皮生长因子和基质金属蛋白酶-9表达的影响

目的研究山慈菇提取液对乳腺癌大鼠肿瘤组织中血管内皮生长因子(VEGF)和基质金属蛋白酶-9(MMP-9)表达水平的影响。方法选取健康雌性未孕SD大鼠为研究对象,用含有二甲基苯蒽的芝麻油建立乳腺癌模型。将造模成功的SD大鼠随机分为模型组、对照组、实验A组和实验B组,每组各16只;另取16只健康大鼠为空白组。模型组和空白组均予以灭菌0.9%Na Cl 1m L,qd,灌胃;对照组予以0.6 mg·m L^-1枸橼酸他莫昔芬1 m L,qd,灌胃;实验A、B组分别予以1.5,3.0 mg·m L^-1山慈菇提取液1 m L,qd,灌胃,5组大鼠均干预6周。比较5组大鼠的抑瘤率、肿瘤组织中VEGF和MMP-9表达水平。结果治疗后,对照组、实验A组和实验B组的抑瘤率分别为70.74%,21.51%和59.88%,两两比较,差异均有统计学意义(均P<0.05)。治疗后,空白组、模型组、对照组、实验A组和实验B组肿瘤组织中VEGF分别为(5454.68±754.37),(35485.58±4638.36),(9975.75±1243.44),(24564.35±3028.43)和(14346.54±1976.56)DPI,肿瘤组织中MMP-9分别为(3353.26±406.34),(29584.37±3856.56),(8143.32±1043.82),(19473.46±2315.47)和(10865.47±1324.43)DPI,两两比较,差异均有统计学意义(均P<0.05)。结论山慈菇提取液能有效抑制乳腺癌大鼠肿瘤生长,且呈剂量依赖性,其可能与抑制肿瘤组织中VEGF及MMP-9的表达有关。