靶向血管内皮生长因子及其受体的抗肿瘤药物研究进展

血管生成对肿瘤的生长和转移起着关键作用,血管内皮生长因子（VEGF）及其受体信号通路是调节肿瘤新生血管生成的重要途径,因此,近年来以VEGF及其受体为作用靶标的抗肿瘤血管生成治疗已经成为研究热点,目前已有多种药物上市或处于临床试验阶段。本文主要综述了VEGF及其受体在肿瘤血管生成调节机制中的作用,同时着重介绍靶向VEGF及其受体的抗肿瘤药物的新近研究进展、临床应用及存在的问题。     

木犀草素对骨缺损成骨修复的作用及机制研究

目的 探讨木犀草素对骨缺损成骨修复的作用及机制。方法 通过网络药理学方法筛选木犀草素治疗骨缺损的作用靶点及潜在通路，利用Hub基因筛选排名前2位的靶点进行分子对接验证，以结合能作为评判标准。对大鼠骨髓间充质干细胞（BMSC）及脐静脉内皮细胞（RUVEC）进行体外实验，采用碱性磷酸酶染色、茜素红S染色、体外血管形成实验进行表型验证，采用Western blot法检测磷脂酰肌醇3激酶（PI3K）、蛋白激酶B1(Akt1)蛋白的表达情况，以验证木犀草素对BMSC成骨分化及RUVEC体外血管形成的作用机制。结果 网络药理学结果显示，木犀草素对骨缺损的血管形成和骨修复作用主要与Akt1、SRC蛋白、雌激素受体1、表皮生长因子受体、环加氧酶2、基质金属蛋白酶9靶点有关，且与PI3K/Akt信号通路关系密切。分子对接结果显示，木犀草素与Akt1、SRC蛋白结合稳定。体外实验结果表明，木犀草素能显著增高BMSC内碱性磷酸酶的表达水平和活性，增加钙盐沉积和钙化结节的数量，促进BMSC的钙化；与木犀草素0μmol/L组比较，木犀草素1、10μmol/L组的RUVEC血管形成能力显著增强、血管长度显著增加，...     

抗血管生成剂Aflibercept

异常的血管生成被认为是某些疾病,如癌症和湿性老年性黄斑变性（AMD）的病理基础,而抑制血管生成的最有效方法之一就是靶向阻断血管内皮生长因子（VEGF）信号通路,包括直接靶向VEGF、     

体外重组IGFBP-6对 Akt,Erk,p38信号通路和血管生成的影响探究

目的 胰岛素样生长因子结合蛋白6(IGFBP-6)是潜在的抗癌新靶点,其能抑制肿瘤血管生成。本研究探讨重组IGFBP-6对Akt,Erk1/2以及p38信号通路的影响以及其是否通过Akt,Erk1/2以及p38信号通路对血管生成发挥作用。方法 通过不同浓度的IGFBP-6重组蛋白处理HUVEC细胞检测Akt,Erk1/2以及p38信号通路是否激活。运用不同浓度IGF配体结合结构域突变的mIGFBP-6体外重组蛋白处理HUVEC细胞检测Akt,Erk1/2以及p38信号通路的激活是否依赖IGF配体。采用这3条通路特异性的抑制剂进行体外血管生成实验,进一步探究IGFBP-6抑制血管生成与Akt,Erk1/2以及p38信号通路的关系。结果 IGFBP-6能够激活HUVEC细胞的Akt,Erk1/2以及p38信号通路,且这种激活作用具有IGF配体非依赖性。Akt,Erk1/2以及p38信号通路的抑制剂不能营救IGFBP-6对血管形成的抑制作用。结论 IGFBP-6抑制血管生成的作用不依赖Akt,Erk1/2以及p38信号通路。本研究为寻找新的以IGFBP-6为靶点的抗血管生成候选化合物,包括海洋来源的抗血管生成的小分子筛选提供了一定的理论依据。     

血管内皮细胞生长因子受体酪氨酸激酶抑制剂

血管生成是人体肿瘤生长和转移的必要条件，抑制肿瘤细胞介导的血管生成已成为近年来寻找新型抗肿瘤药物的一个主要研究方向，血管内皮细胞生长因子（VEGF）是体内活性最强，专属性最高的促血管生成因子，故成为寻找血管生成抑制剂的重要靶点，其中靶向VEGF受体酪氨酸激酶的抑制剂令人最为关注，本文综述VEGF及其受体酪氨酸酶抑制剂的研究进展，探讨了各类抑制剂的构效关系。     

CXCR4靶向PI3K-Akt信号通路抑制小细胞肺癌血管生成

目的 探讨在小细胞肺癌(SCLC)中CXC趋化因子受体4(CXCR4)靶向PI3K/Akt信号通路对血管内皮生长因子(VEGF)表达及肿瘤血管生成的影响.方法 采用免疫蛋白印迹法检测PI3K激动剂/抑制剂(YS-49/LY294002)和CXCR4激动剂/拮抗剂(NUCC-390/AMD3100)对PI3K/Akt信号...     

以c-Met为靶点的小分子酪氨酸激酶抑制剂的研究进展

酪氨酸激酶在细胞信号转导通路中起着极其重要的作用,而其中HGF/c-Met信号通路与血管新生和肿瘤生长过程密切相关。因此,抑制HGF/c-Met通路成为靶向抗肿瘤治疗的新手段。本文着重介绍近期已上市和处于临床后期的c-Met抑制剂的研究进展。     

VEGF通路和Notch通路在肿瘤血管生成中的相互作用及靶向药物的研发

综述VEGF通路和Notch通路在肿瘤血管生成中的作用,重点阐述两者的相互作用在肿瘤血管形成中的意义,并概述以这两条信号通路为靶点的抗肿瘤药物研发现状。     

金荞麦中优效组分的网络药理学研究

目的:研究金荞麦中优效组分的药理作用及可能的分子机制。方法:基于网络药理学,以类药性(DL)>0.18和生物利用度(OB)>30%为标准,借助中药整合药理学计算平台(TCMSP)筛选金荞麦中的优效组分;利用药效基团匹配与潜在识别靶标数据库(PharmMapper)获取金荞麦优效组分的潜在作用靶点;利用生物学信息注释数据库(DAVID)对获得的靶点蛋白进行京都基因与基因组数据库(KEGG)信号通路分析和基因本体(GO)生物过程(包括生物过程、分子功能及细胞组分)富集分析(均以P<0.05为标准)。结果:从金荞麦中共筛选出15种优效组分[如槲皮素、木犀草素、原矢车菊素B_1、(+)儿茶素、β-谷甾醇等]和114个潜在作用靶蛋白[如雌二醇17-β-脱氢酶1、环腺苷酸(cAMP)特异性3,5-环磷酸二酯酶4D、维生素D_3受体、尿苷胞苷激酶2、HRAS基因编码的三磷酸尿苷酶等];涉及34条重要通路,如丝裂原活化蛋白激酶(MAPK)信号通路、血管内皮生长因子(VEGF)信号通路、趋化因子信号通路和胰岛素信号通路,其中与癌症相关的通路11条,与代谢相关的通路7条,与内分泌系统相关的通路4条;涉及的分子功能有类固醇激素受体活性、配体依赖的核受体活性、蛋白激酶活性等,细胞组分有细胞液、细胞碎片、可溶性部分等,生物过程有细胞凋亡的调节、有机物反应的过程、内源性刺激反应的过程等。结论:金荞麦可能通过MAPK信号通路、VEGF信号通路、趋化因子通路、胰岛素信号通路等发挥抗肿瘤、抗炎及调节糖脂代谢的作用。     

柠檬苦素靶向VEGF/VEGFR2通路对肺癌A549细胞的增殖和血管生成的影响

目的:探讨柠檬苦素靶向血管内皮生长因子(VEGF)/血管内皮细胞生长因子受体2(VEGFR2)通路对肺癌A549细胞的增殖和血管生成的影响。方法:肺癌A549细胞分为空白对照组、氟尿嘧啶组(500μg·ml^-1)、柠檬苦素低、高剂量组(100,1000μg·ml^-1);MTT法测定各组细胞增殖水平,甲醇固定吉姆沙染色测定单克隆形成数目,BD Matrigel基质测定血管形成水平,transwell板测定相对迁移率,Axv-FiTC试剂盒测定细胞凋亡水平,RT-PCR法及酶联免疫吸附法测定VEGF、VEGFR2 mRNA及MEK1/2、ERK1/2蛋白表达。结果:柠檬苦素低、高剂量组和氟尿嘧啶组A值、存活率、克隆形成数目、相对总血管长度、相对总血管数目、相对迁移率、VEGF、VEGFR2 mRNA及MEK1/2、ERK1/2蛋白水平低于空白对照组,凋亡率高于空白对照组(P<0.05),且剂量-效应关系明显(P<0.05);柠檬苦素低剂量组A值、存活率、克隆形成数目、相对总血管长度、相对总血管数目、相对迁移率、VEGF、VEGFR2 mRNA及MEK1/2、ERK1/2蛋白水平高于氟尿嘧啶组,凋亡率低于氟尿嘧啶组(P<0.05);柠檬苦素高剂量组上述指标与氟尿嘧啶组比较差异无统计学意义(P>0.05)。结论:柠檬苦素能抑制肺癌A549细胞增殖、血管生成、侵袭、诱导肺癌A549细胞凋亡;其机制可能与柠檬苦素抑制VEGF/VEGFR2诱导的MEK1/2、ERK1/2磷酸化有关。     

Effect of luteoin in delaying cataract in STZ-induced diabetic rats

Luteolin, a flavonoid rich in many plants, has shown various pharmacological effects including anti-inflammation, anti-oxidant, anti-tumor, cardioprotective and neuroprotective properties. At present, inflammation and oxidative stress have been recognized to be two important contributing factors to the development of diabetic cataract. The aim of this study is to investigate the effects of luteolin on diabetes-induced oxidative stress and inflammation in the lens of rats. A diabetic rat model was induced by intraperitoneally giving streptozotocin at a dosage of 60 mg/kg, and then the rats were treated by orally administration of luteolin 25, 50 and 100 mg/kg for 12 weeks. The results showed that luteolin administration could increase the antioxidant capacity such as glutathione (GSH) and glutathione peroxidase (GPx) activity, and decreased malondialdehyde (MDA) level in the lens of diabetic rats. Luteolin also inhibited diabetes-induced elevation of interleukin-1 beta (IL-1β), vascular endothelial growth factor and nuclear factor-κB (NF-κB) mRNA and protein expression in lens. Moreover, in the high dose group (100 mg/kg), lens GSH level was decreased to normal compared to control group. The degree of oxidative and inflammatory damage was significantly reduced in luteolin-treated rats. These data suggested that luteolin can be an effective protection candidate of diabetes-induced lens neurodegeneration by inhibiting the levels of inflammatory mediators and oxidative stress.     

Saikosaponins-b suppresses tumor growth and angiogenesis of hepatocellular carcinoma by regulating VEGF/ERK/HIF-1α signal pathway

OBJECTIVE Angiogenesis therapy has attracted interest as a potential treatment for hepatocellular carcinoma(HCC).In this study,we investigated the anti-proliferative activities and antiangiogenesis effects of saikosaponins(SS)-b on hepatocellular carcinoma(HCC)and its regulation on VEGF/ERK/HIF-1 αsignal pathway.METHODS H22 hepatoma-bearing mice model and HepG-2 cells were used to study the anti-tumor and anti-angiogenesis effects of SS-b in vivo and in vitro.Pathological change of tumor tissue was observed by HE staining,the microvascular changes were detected by immunohistochemical method.The effects of SS-b on angiogenesis were examined by using the chick embryo chorioallantoic membrane(CAM)model.The effects of SS-b on proliferation,migration and invasion were investigated by MTT assay,scratch wound healing assay and transwell assay inhuman umbilical vein endothelial cell(HUVEC)and HepG2 cells in vitro.Vascular endothelial growth factor(VEGF),matrix metalloproteinase-2/9(MMP-2/9),hypoxia-inducible factor-1α(HIF-1α)expression and the phosphorylation of extracellular regulated kinase(ERK)were analyzed using RT-PCR and Westernblot.RESULTS SS-b effectively inhibited the tumor growth of H22 mice in vivo.The inhibitory rate of tumor was 49.1%,50.7%,66.1%in SS-b 5,10 and 20 mg·kg-1group respectively.HE staining results showed that SS-b induced tumor necrosis and nuclear dissolution in H22 mice.Moreover,SS-b also reduced the number of microvessels of tumor tissue in H22 mice significantly and suppressed the angiogenesis of CAM induced by b-FGF.SS-b had an obvious inhibitory effect on cell proliferation,migration and invasion of HUVEC cells and HepG-2 cells.These effects were associated with downregulation of the expression of MMP2/9 and suppression of VEGF/ERK/HIF-1αsignaling in H22 mice and Hep-G2 cells.CONCLUSION Our findings showed that SS-b exerts anti-tumor effects by inhibiting tumor angiogenesis via regulating VEGF/ERK/HIF-1α signal pathway in vivo and in vitro.     

A highly potent and selective farnesyltransferase inhibitor ABT-100 in preclinical studies

Ras mutation has been detected in approximately 20-30% of all human carcinomas, primarily in pancreatic, colorectal, lung and bladder carcinomas. The indirect inhibition of Ras activity by inhibiting farnesyltransferase (FTase) function is one therapeutic intervention to control tumor growth. Here we report the preclinical anti-tumor activity of our most advanced FTase inhibitor (FTI), ABT-100, and a direct comparison with the current clinical candidates. ABT-100 is a highly selective, potent and orally bioavailable FTI. It broadly inhibits the growth of solid tumors in preclinical animal models. Thus, ABT-100 is an attractive candidate for further clinical evaluation. In addition, our results provide plausible insights to explain the impressive potency and selectivity of ABT-100. Finally, we have demonstrated that ABT-100 significantly suppresses the expression of vascular endothelial growth factor (VEGF) mRNA and secretion of VEGF protein, as well as inhibiting angiogenesis in the animal model.     

Vascular endothelial growth factor (VEGF) inhibition--a critical review

Angiogenesis, or formation of new blood capillaries from preexisting vessels, plays both beneficial and damaging roles in the organism. It is a result of a complex balance of positive and negative regulators, and vascular endothelial growth factor (VEGF) is one of the most important pro-angiogenic factors involved in tumor angiogenesis. VEGF increases vascular permeability, which might facilitate tumor dissemination via the circulation causing a greater delivery of oxygen and nutrients; it recruits circulating endothelial precursor cells, and acts as a survival factor for immature tumor blood vessels. The endotheliotropic activities of VEGF are mediated through the VEGF-specific tyrosine-kinase receptors: VEGFR-1, VEGFR-2 and VEGFR-3. VEGF and its receptors play a central role in tumor angiogenesis, and therefore the blockade of this pathway is a promising therapeutic strategy for inhibiting angiogenesis and tumor growth. A number of different strategies to inhibit VEGF signal transduction are in development and they include the development of humanized neutralizing anti-VEGF monoclonal antibodies, receptor antagonists, soluble receptors, antagonistic VEGF mutants, and inhibitors of VEGF receptor function. These agents can be divided in two broad classes, namely agents designed to target the VEGF activity and agents designed to target the surface receptor function. The main purpose of this review is to summarize all the available information regarding the importance of the pro-angiogenic factor VEGF in cancer therapy. After an overview of the VEGF family and their respective receptors, we shall focus our attention on the different VEGF-inhibitors existent nowadays. Agents based upon anti-VEGF therapy have provided solid proofs about their success, and therefore we believe that a critical review is of the utmost importance to help researchers in their future work.     

Specific inhibition of hypoxia-inducible factor (HIF)-1 alpha activation and of vascular endothelial growth factor (VEGF) production by flavonoids

Screening using a reporter under the control of the hypoxia-response element (HRE) identified several flavonoids and homoisoflavonoids that inhibit the activation of HRE under hypoxic conditions. Among various compounds, isorhamnetin, luteolin, quercetin, and methyl ophiopogonanone B (MOB) were effective at 3 to 9 microg/ml in inhibiting the reporter activity. The expression of vascular endothelial growth factor (VEGF) mRNA during hypoxia was also inhibited by MOB in HepG2 cells, but the effective doses were 10 to 20 microg/ml. MOB caused destabilization of hypoxia-inducible factor (HIF)-1alpha, as revealed by Western blotting, that was dependent on proteasome activity and the tumor suppressor, p53. The tubular formation and migration of human umbilical vein endothelial cells was also inhibited by MOB. MOB is expected to act as an inhibitor of angiogenesis.     

血管内皮生长因子及其受体在抗肿瘤治疗应用的研究进展

肿瘤的生长依赖肿瘤新生血管的形成。血管内皮生长因子（VEGF）是一类能促进血管生成的细胞因子，能诱导细胞的有丝分裂和调节内皮细胞的通透性。VEGF及其受体介导的肿瘤血管新生在肿瘤的生长和转移中具有重要的作用。本文综述了VEGF及其受体的分类、作用机制及在抗肿瘤治疗中的应用。     

Vascular endothelial cell growth factor (VEGF), an emerging target for cancer chemotherapy

Angiogenesis is a process of development and of growth of new capillary blood vessels from pre-existing vessels. When pathological, it contributes to the development of numerous types of tumors, and the formation of metastases. In order to grow, carcinoma need new blood vessels to form so that they can feed themselves. Therefore, nowadays the concept according to which the development of cancer is angiogenesis dependent is generally recognized. This concept makes the control of tumoral angiogenesis one of the promising therapeutic ways in cancerology. The transition from the latent phase to the invasive and metastatic phase of a cancer is linked to what is called the angiogenic switch. It implies complex cellular and molecular interactions between cancerous cells, endothelial cells and the components of the extra-cellular matrix and namely the existence of specific proteins secreted by the tumoral cells able to stimulate the proliferation of capillary endothelial cells. Among them, VEGF, Vascular Endothelial Growth Factor was found in several types of tumors. It has shown a tumoral angiogenic activity in vitro and in vivo, and thus is a privileged target for the control of angiogenesis in an anti-tumoral goal. The role of VEGF in tumoral angiogenesis has been extensively studied. It has been proved to undergo as well autocrine as paracrine stimulation of tumoral angiogenesis. During the last few years, several members of the VEGF family have been described namely the VEGF-A, B, C, D, E and placenta growth factor (PlGF) among which VEGF-A (121 aminoacids) plays a role of prime importance in angiogenesis. VEGF is a 45 kDA glycoprotein, homodimeric, basic, and able to bind heparin. The three-dimensional structure of VEGF has been recently determined, by X-rays diffraction, and NMR spectroscopy. The different forms of the VEGF bind to receptors that exhibit a tyrosine-kinase activity (RTK). The specific action of the VEGF on the endothelial cells is mainly regulated by two types of RTK of the VEGF family, VEGFR1, or Flt-1, and VEGFR2, or KDR/Flk-1. Mutagenesis studies have shown that only a small number of VEGF residues are important and essential for the binding with RTK. Data described to date from the studies of VEGF/RTK interactions agree to the hypothesis that KDR receptor is the main human receptor responsible for the VEGF activity in both physiological and pathological vascular development, and VEGF-KDR signalling pathway has been validated as a priority target for the development of anti- and pro- angiogenic agents. Therefore angiogenesis mediated by VEGF constitutes a new target for anti-cancer therapy which has explored through different ways of intervention aiming at the blocking of the tumoral angiogenesis. The main ones are: -Struggle against the stroma degradation and invasion by the neo-vessels -Inhibition of activated endothelial cells. -Inhibition of angiogenic factors production and of their receptors. -Inhibition of the VEGF signal pathway, by peptides blocking the bond between VEGF and its receptors through the inhibition of intracellular transduction of VEGF signal. In conclusion, this bibliographic study allows to situate works of medicinal chemistry in the context of present knowledge concerning the vascular endothelial growth factor (VEGF) and its role in angiogenesis.