肿瘤血管生成抑制物的研究

肿瘤的生长及转移依赖于血管的生成(angiogenesis)，抑制肿瘤血管生成可以抑制肿瘤的生长，已经成为不同于常规肿瘤治疗的方法和热点。与直接杀伤肿瘤细胞的化学药物治疗相比，血管生成抑制剂有以下优点：(1)血管生成抑制剂直接作用于血管内皮细胞，而抗癌药物经组织扩散时受到组织坏死、纤维化、组织内高压的影响，常常在组织内达不到有效浓度；(2)血管内皮细胞属正常细胞，其基因型稳定，不易产生耐药性，而肿瘤细胞基因型不稳定，易产生耐药性；     

恶性骨肿瘤新血管形成机制研究进展

骨肉瘤、Ｅｗｉｎｇ'ｓ肉瘤和软骨肉瘤等恶性骨肿瘤多为高度血管化肿瘤，严重危害青少年患者，病死率高。虽然包括手术和化疗在内的综合治疗改善了这些患者的预后，但相当一部分患者还是很快发生转移，而这正是主要的死因。恶性骨肿瘤具有多种维持和增加血供的机制，因而使得肿瘤生长及转移。本文就有关恶性骨肿瘤新血管形成的分子生物学机制方面的研究进展作一综述。     

肿瘤血管生成拟态的研究进展

肿瘤需要机体血液供应来满足生长的需要和进行播散。经典的血管生成理论认为：当实体肿瘤直径大于2mm时,需要诱导生成新的血管来获取血供,新的血管生成包括血管再生和血管形成两种方式,前者通过激活瘤体周围的宿主血管内皮细胞增生、迁移、芽生、向瘤组织内生长形成血管网;后者则是通过动员骨髓中血管内皮前体细胞,     

大肠癌巨─微血管构筑的临床研究

为了探讨大肠癌和其间质血管的关系，我们研究了48例大肠癌标本不同部位的巨─-微血管构筑。方法：用癌瘤标本造影摄X线片、立体显微镜和微机图象定量分析。结果显示：癌中心血管稀疏或为无血管的坏死区及血管破坏；癌远近端瘤组织内血管增多增粗，畸形及紊乱；其血管定量参数与癌中心和癌远近端肠粘膜相比有显著差异（P＜O．05，P＜0．01）。结论：①大肠癌的发生发展依赖于血管形成和细胞增殖。②在理论上解释了大肠癌的临床病理过程。③大肠癌的恶性程度与其血管密度间似有负相关的趋势。④探讨了其临床应用价值。     

肿瘤血管形成调节剂

血管形成即一个微血管床的发展是许多重要的生理过程所必需的，正常的生长与分化等过程均伴有血管形成。在某些病理性疾病中常发生无控制的血管形成，如实体瘤等组织中血管明显增殖，肿瘤细胞分泌血管形成调节因子，这些因子能够诱导宿毛细胞管新生并长入肿瘤组织。     

血管生长因子与肿瘤血管生成

血管生成对恶性肿瘤的发生、发展和预后至关重要。就血管内皮生长因子、血小板源性内皮细胞生长因子、碱性成纤维细胞生长因子等血管生成调节因子的研究进展进行综述,介绍了抗血管生存治疗肿瘤的现状和发展动向。     

VEGF在大鼠脾内移植瘤模型中的表达及其与肿瘤血管形成、侵袭和转移的关系

目的探讨VEGF在大鼠移植瘤模型中的表达及意义。方法采用ELISA检测大鼠血清VEGF浓度,采用免疫组化法检测VEGF在肿瘤组织中的表达,F8因子肿瘤微血管染色分析肿瘤血管形成。结果实验大鼠血清VEGF水平接种后第一天明显升高,后两周保持稳定。大鼠脾内移植瘤模型中血清VEGF表达与肿瘤组织微血管密度、肝转移显著相关,γ=0.92,P〈0.05。肝转移肿瘤细胞胞质VEGF染色较深。16只大鼠移植瘤模型中肝转移9例,血清VEGF浓度为（2.57±0.68）ng/ml,未发生肝转移7例,VEGF浓度为（1.83±0.37）ng/ml（P〈0.05）;腹腔播散10例,VEGF浓度为（2.47±0.71）ng/ml,无腹腔播散6例,VEGF浓度为（1.86±0.39）ng/ml（P〈0.05）;出现血性腹腔积液11例,VEGF浓度为（2.47±0.66）ng/ml,未见血性腹腔积液5例,VEGF浓度为（1.75±0.38）ng/ml（P〈0.05）。结论实验大鼠中血清VEGF表达与肿瘤血管密度、肝转移、腹腔播散、血性腹腔积液有关。     

血管外皮细胞瘤——附7例报告

20年间我们共收治血管外皮细胞瘤7例,其中男性5例,女性2例。年龄30—56岁,中位43.9岁。发生于头颈部1例,躯干3例,上肢1例,下肢1例,腹膜后1例。治疗方法以手术为主(包括1例探查术),其中单纯手术1例,手术加放疗5例,手术加放疗加化疗1例。治疗后3例局部复发,1例远处转移,3例局部复发伴远处转移,转移部位均为肺。随访结果:生存5年以上6例,10年以上4例,10年生存率为57％[4/7].     

肺癌的抗血管生成基因治疗

血管生成 (ａｎｇｉｏｇｅｎｅｓｉｓ)是指从已存在的微血管床上芽生出新的以毛细血管为主的血管系统的过程。大量证据表明 ,恶性实体肿瘤是血管新生依赖疾病 ,实体肿瘤的生长如果没有新生血管 ,不会超过 1～ 2ｍｍ ,并且原发肿瘤的血管生长使肿瘤易于转移[1、2 ] 。肺癌是恶性程度较高的肿瘤之一 ,近年来 ,随着分子生物学和分子病理学的进展 ,抗肿瘤血管生成治疗作为治疗肺癌的一项重要手段 ,已经越来越受到人们的重视。研究发现 ,生长中的肺癌组织同样高度表达编码血管生成的基因[3～ 5] 。 1992年 ,Ｍａｃｃｈｉａｒｉｎｉ等又报道非小细…     

癌变过程中血管生成现象的动物实验研究

采用血管铸型扫描电镜以及显微图像分别测量血管密度的方法观察了二甲基苯并蒽诱发金地鼠颊囊癌过程中的血管生成现象发现：病变出现单纯性增生阶段就有血管的增生现象；病变异常增生阶段出现明显血管生成现象；癌变后血管极度增生，发育不良。血管密度的测量结果：随癌变的发展过程，ＶＤ值逐步升高。正常组织粘膜下ＶＤ值仅为８．３４％；单纯性增生阶段升高至１０．６％；异常增生阶段则高达１４．６％。     

结肠癌组织NRP-1和VEGF表达及其与预后相关性

目的结肠癌的发生发展过程与肿瘤血管生成密切相关,神经纤毛蛋白-1(neuropilin-1,NRP-1)和血管内皮生长因子(vascular endothelial growth factor,VEGF)在肿瘤血管生成中发挥重要作用。本研究旨在探讨结肠癌组织NRP-1和VEGF表达及其预后的关系。方法收集2010-08-01-2012-05-31南华大学附属南华医院普外胃肠病区手术切除、具有完整资料、术后经病理确诊的结肠癌及癌旁(>5cm)组织标本73例,采用免疫组织化学法检测NRP-1及VEGF在结肠癌及癌旁正常组织的表达;另外选取2016年南华大学附属南华医院切除结肠癌新鲜组织及癌旁组织(距癌组织>5cm)16对,采用蛋白质印迹法检测NRP-1及VEGF表达。结果免疫组化结果显示,与结肠癌癌旁组织比较,结肠癌组织中NRP-1及VEGF呈高表达,χ^2=55.857,P<0.001;χ^2=44.042,P<0.001。蛋白质印迹法检测结果显示,新鲜结肠癌组织中NRP-1及VEGF蛋白呈高表达,而癌旁组织中表达降低,差异有统计学意义,t=-63.238,P<0.001;t=-78.712,P<0.001。结肠癌组织中NRP-1和VEGF高表达均与肿瘤大小、TNM分期、淋巴结有无转移有关联,差异有统计学意义,P<0.05;癌胚抗原(carcinoembryonic antigen,CEA)的数值与NRP-1表达有关联(χ^2=15.966,P=0.002),而与VEGF表达无统计学意义的关联,χ^2=0.061,P=0.862;Cox多因素回归分析显示,CEA(RR=4.851,95%CI:1.013~23.427)、肿瘤大小(RR=0.157,95%CI:0.017~1.228)、TNM分期(RR=5.419,95%CI:2.179~32.479)、淋巴结转移(RR=0.137,95%CI:0.023~0.728)是NRP-1阳性表达的独立影响因素;生存分析显示,NRP-1阳性表达组患者生存周期短于阴性患者,χ^2=5.081,P=0.029。结论NRP-1参与结肠癌的血管生成,并导致预后不良,提示NRP-1在结肠癌发生发展中起重要作用,为评估结肠癌预后及研究靶向药物提供新的思路。     

Neuropilin-1 suppresses tumorigenic properties in a human pancreatic adenocarcinoma cell line lacking neuropilin-1 coreceptors

Neuropilin-1 (NRP-1) was first described as a coreceptor implicated in neuronal guidance that bound members of the semaphorin/collapsin family. NRP-1 is also expressed in endothelial cells and is believed to promote angiogenesis by acting as a coreceptor with vascular endothelial growth factor (VEGF) receptor 2. Recent studies suggest that NRP-1 can function through both a VEGF-dependent and VEGF-independent fashion. Expression of NRP-1 has been shown in many human tumors, including pancreatic adenocarcinomas. The exact role of NRP-1 in tumor cells is unknown, particularly in cells that lack the NRP-1 coreceptors VEGF receptor 2 and Plexin-A1. To discern the regulatory role(s) of NRP-1 in pancreatic adenocarcinoma that lack these coreceptors, we overexpressed both full-length NRP-1 and a deletion form of NRP-1 that does not interact with semaphorin or VEGF. Overexpression of either isoform reduced several key tumorigenic properties, including anchorage-independent cell growth and migration in vitro, and resulted in reduced tumor incidence and tumor volume in vivo. Conversely, reduction of NRP-1 expression by small interfering RNA targeting led to enhanced tumor growth. Thus, NRP-1 may play distinct growth regulatory roles in different tumor types, and altering NRP-1 expression or function may be a means of influencing the growth of pancreatic cancers.     

VEGF exerts an angiogenesis-independent function in cancer cells to promote their malignant progression

VEGF/vascular permeability factor (VEGF/VPF or VEGF-A) is a pivotal driver of cancer angiogenesis that is a central therapeutic target in the treatment of malignancy. However, little work has been devoted to investigating functions of VEGF that are independent of its proangiogenic activity. Here, we report that VEGF produced by tumor cells acts in an autocrine manner to promote cell growth through interaction with the VEGF receptor neuropilin-1 (NRP-1). Reducing VEGF expression by tumor cells induced a differentiated phenotype in vitro and inhibited tumor forming capacity in vivo, independent of effects on angiogenesis. Autocrine activation of tumor cell growth was dependent on signaling through NRP-1, and Ras was determined to be a critical effector signaling molecule downstream of NRP-1. Our findings define a novel function for VEGF in dedifferentiation of tumor cells expanding its role in cancer beyond its known proangiogenic function. Cancer Res; 72(16); 3912-8. ?2012 AACR.     

Role of NRP-1 in VEGF-VEGFR2-Independent Tumorigenesis

Recent studies suggest that neuropilin-1 (NRP-1) promotes angiogenesis mainly via VEGF and its receptors. It promotes tumorigenesis via formation of the NRP-1/ VEGF (vascular endothelial growth factor)/VEGFR2 (vascular endothelial growth factor receptor 2) complex. In addition to VEGF and its receptors, NRP-1 also binds with other growth factors such as platelet-derived growth factor (PDGF) and platelet-derived growth factor receptor (PDGFR). PDGF plays important roles in cellular proliferation and, in particular, blood vessel formation. Moreover, recent studies show that NRP-1 promotes angiogenesis via the NRP-1-ABL pathway, but independent of VEGF-VEGFR2. RAD51 is a protein involved in the signaling pathways of NRP1-ABL and PDGF(R), the expression of which is positively associated with cell radioresistance and chemoresistance. NRP-1 activates the signaling pathways of ABL and PDGF(R) to upregulate RAD51, which induces resistance to radiotherapy and chemotherapy in cancer cells. Furthermore, NRP-1 activates the tumor microenvironment by binding with fibronectin and activating ABL, thereby promoting tumor growth. Inhibition of NRP-1 may overcome the limitations of individually inhibiting the VEGF-VEGFR2 pathway in cancer therapy and provide new ideas for cancer treatment. Therefore, we review the role of NRP-1 in VEGF-VEGFR2-independent tumorigenesis.

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Expression and regulation of the novel vascular endothelial growth factor receptor neuropilin-1 by epidermal growth factor in human pancreatic carcinoma

BACKGROUND: It was recently shown that neuropilin-1 (NRP-1), which was described originally as a receptor for the semaphorins/collapsins (ligands involved in neuronal guidance), is a coreceptor for vascular endothelial growth factor (VEGF) and increases the affinity of specific isoforms of VEGF to its receptor, VEGF-R2. METHODS: The authors investigated the expression and regulation of NRP-1 in human pancreatic adenocarcinoma specimens and cell lines. RESULTS: Immunohistochemical analysis revealed that NRP-1 was expressed in 12 of 12 human pancreatic adenocarcinoma specimens but was absent in nonmalignant pancreatic tissue. Northern blot analysis revealed NRP-1 mRNA expression in 8 of 11 human pancreatic adenocarcinoma cell lines. NRP-1 mRNA expression was increased by epidermal growth factor (EGF) but not by tumor necrosis factor alpha in several of the human pancreatic adenocarcinoma cell lines studied. Treating human Panc-48 adenocarcinoma cells with EGF activated Akt and Erk but not P-38. Blockade of the phosphatidylinositol-3 kinase (PI-3K)/Akt, mitogen-activated protein kinase (MAPK)/Erk, or P-38 pathways abrogated EGF-induced NRP-1 expression. Finally, EGF receptor blockade in vivo led to a decrease in NRP-1 expression in an orthotopic model of human pancreatic carcinoma. CONCLUSIONS: NRP-1 is expressed in most human pancreatic adenocarcinomas and cell lines but not in nonmalignant pancreatic tissue. EGF regulates NRP-1 expression through the PI-3K/Akt and MAPK/Erk signaling pathways, and blockade of the EGF receptor is associated with decreased expression of NRP-1 in vivo. NRP-1 may act as a coreceptor for VEGF in pancreatic carcinoma, as it does in other tumor systems, thereby enhancing angiogenesis and the effect of VEGF on the growth of pancreatic adenocarcinoma.     

Induction of neuropilin-1 and vascular endothelial growth factor by epidermal growth factor in human gastric cancer cells

The epidermal growth factor receptor (EGF-R) pathway plays a pivotal role in the progression of human gastric cancer. The angiogenic factor vascular endothelial growth factor (VEGF) has been shown to be induced by EGF in various cancer cell lines. Neuropilin-1 (NRP-1) acts as a coreceptor for VEGF-165 and increases its affinity for VEGF receptor 2 (VEGFR-2) in endothelial cells. Furthermore, NRP-1 has been found to be expressed by tumour cells and has been shown to enhance tumour angiogenesis and growth in preclinical models. We examined the expression of NRP-1 mRNA and EGF-R protein in seven human gastric cancer cell lines. NRP-1 expression was expressed in five of seven cell lines, and EGF-R expression closely mirrored NRP-1 expression. Moreover, in EGF-R-positive NCI-N87 and ST-2 cells, EGF induced both NRP-1 and VEGF mRNA expression. C225, a monoclonal antibody to EGF-R, blocked EGF-induced NRP-1 and VEGF expression in NCI-N87 cells in a dose-dependent manner. The treatment of NCI-N87 cells with EGF resulted in increases in phosphorylation of Erk1/2, Akt, and P38. Blockade of the Erk, phosphatidylinositol-3 kinase/Akt, or P38 pathways in this cell line prevented EGF induction of NRP-1 and VEGF. These results suggest that regulation of NRP-1 expression in human gastric cancer is intimately associated with the EGF/EGF-R system. Activation of EGF-R might contribute to gastric cancer angiogenesis by a mechanism that involves upregulation of VEGF and NRP-1 expression via multiple signalling pathways.     

Neuropilin-1及VEGF在胃癌组织中的表达与微血管生成的关系

  目的  探讨胃癌组织中神经纤毛蛋白-1（Neuropilin-1,NRP-1）、血管内皮生长因子（VEGF）的表达与微血管生成及胃癌生物学行为的关系和意义。  方法  应用RT-PCR法检测自2011年5月至2013年5月天津医科大学肿瘤医院72例手术切除的胃癌组织及癌旁正常组织中NRP-1 mRNA和VEGF mRNA的表达,免疫组织化学SP法检测组织中CD105标记的新生血管内皮细胞并测定微血管密度（MVD）,统计分析胃癌组织中NRP-1 mRNA、VEGF mRNA的表达与临床病理因素及MVD之间的关系。  结果  胃癌组织中NRP-1 mRNA、VEGF mRNA的表达及MVD计数均高于正常组织（P＜0.05）,且与肿瘤的浸润深度、淋巴结转移密切相关（P＜0.05）;胃癌组织中NRP-1 mRNA表达和VEGF mRNA表达呈正相关（r=0.58,P＜0.01）,NRP-1 mRNA的表达与MVD呈正相关（r= 0.52,P＜0.01）,VEGF mRNA的表达与MVD呈正相关（r=0.74,P＜0.01）。  结论  Neuropilin-1及VEGF的高表达促进了肿瘤微血管生成且与胃癌的进展密切相关,表达存在协同作用,两者的联合检测可在一定程度上判断胃癌侵袭性及进展,并对指导肿瘤抗血管治疗具有一定的价值。      

Pleiotrophin Exerts Its Migration and Invasion Effect through the Neuropilin-1 Pathway

Pleiotrophin (PTN) is a pleiotropic growth factor that exhibits angiogenic properties and is involved in tumor growth and metastasis. Although it has been shown that PTN is expressed in tumor cells, few studies have investigated its receptors and their involvement in cell migration and invasion. Neuropilin-1 (NRP-1) is a receptor for multiple growth factors that mediates cell motility and plays an important role in angiogenesis and tumor progression. Here we provide evidence for the first time that NRP-1 is crucial for biological activities of PTN. We found that PTN interacted directly with NRP-1 through its thrombospondin type-I repeat domains. Importantly, binding of PTN to NRP-1 stimulated the internalization and recycling of NRP-1 at the cell surface. Invalidation of NRP-1 by RNA interference in human carcinoma cells inhibited PTN-induced intracellular signaling of the serine-threonine kinase, mitogen-activated protein MAP kinase, and focal adhesion kinase pathways. Accordingly, NRP-1 silencing or blocking by antibody inhibited PTN-induced human umbilical vein endothelial cell migration and tumor cell invasion. These results suggest that NRP-1/PTN interaction provides a novel mechanism for controlling the response of endothelial and tumoral cells to PTN and may explain, at least in part, how PTN contributes to tumor angiogenesis and cancer progression.     

L1 on ovarian carcinoma cells is a binding partner for Neuropilin-1 on mesothelial cells

The progression of ovarian cancer is driven by a variety of cellular factors that are incompletely understood. Binding of tumor cells to normal cells and to soluble factors influence tumor growth, angiogenesis and the stimulation of vascular permeability leading to ascites production. L1 adhesion molecule is overexpressed in ovarian carcinoma and is associated with bad prognosis. One receptor for L1 is Neuropilin-1 (NRP-1) that is also known as a receptor for VEGF(165). In the nervous system a complex of NRP-1 and L1 transmits signals by the neurorepellant Sem3A that is critical for the control of neurite outgrowth. NRP-1 has also been detected in human carcinomas but its function remains unknown. Here, we have examined NRP-1 expression in ovarian carcinoma cell lines and tissue. We report that little NRP-1 protein was detected in primary ovarian carcinoma tissues or established cell lines although mRNA for soluble and transmembrane NRP-1 were detected by RT-PCR. Instead, we observed strong expression of NRP-1 in mesothelial cells, which form the lining of the peritoneum. NRP-1 could serve as an isolation marker for primary mesothelial cells present in ascites fluid. We demonstrate that ovarian cancer cells expressing L1 can bind to NRP-1 overexpressing cells and mesothelial cells. Likewise, soluble L1 isolated from ascites of patients or produced as a fusion protein could bind to NRP-1 overexpressing cells and a direct interaction was demonstrated at the protein level. These findings suggest that L1 can support the binding of ovarian carcinoma cells to mesothelial cells via NRP-1. The L1-NRP-1 binding pathway could contribute to the growth of ovarian carcinomas and to reciprocal signalling between mesothelial cells and tumors.     

NRP-1单克隆抗体对乳腺癌裸鼠移植瘤生长的影响

 目的 探讨NRP-1单克隆抗体（NRP-1 MAb）的特异性，以及不同剂量的NRP-1 MAb治疗乳腺癌裸鼠移植瘤的疗效。方法 Western blot和共聚焦免疫荧光法检测NRP-1 MAb是否识别MCF7细胞上NRP-1蛋白。将MCF7细胞接种于BALB/c裸鼠皮下建立乳腺癌细胞移植瘤模型，并进行瘤组织传代。传代的肿瘤体积生长至300~500 mm3时，随机分为对照组、NRP-1 MAb低剂量组、中剂量组和高剂量组，每组6只，给药7次。观察荷瘤裸鼠一般状况，测量瘤体大小及裸鼠体重。实验结束时剥离瘤体称重，提取组织蛋白，Western blot检测组织中VEGF蛋白和NRP-1蛋白的表达量。结果 NRP-1MAb成功识别MCF7细胞上的NRP-1蛋白；NRP-1 MAb能够有效抑制MCF7细胞裸鼠移植瘤的生长，低剂量组（1 mg/kg）抑瘤率为47.01%，中剂量组（5 mg/kg）抑瘤率为65.70%，高剂量组（10 mg/kg）抑瘤率为69.19%。。结论 NRP-1 MAb能够识别并有效结合MCF7细胞膜上的NRP-1蛋白，且可抑制MCF7细胞移植瘤的生长，NRP-1 MAb抑制移植瘤的增长可能与下调NRP-1和VEGF表达有关。