Cox-2抑制剂celebrex对胰腺癌PC-3细胞系VEGF表达的影响

目的：探讨选择性环氧合酶-2(COX-2)抑制剂celebrcx对胰腺癌PC-3细胞系血管内皮生长因子(VEGF)表达的影响。方法：应用逆转录-聚合酶链反应(RT-PCR)和酶联免疫吸附测定(ELISA)方法，检测选择性COX-2抑制剂celebrex与胰腺癌PC-3细胞株VEGF表达间的时-效关系和量-效关系。结果：celebrex在一定时间和剂量范围内可抑制PC-3细胞中VEGF的表达。结论：COX-2可能参与了胰腺癌PC-3细胞株VEGF的分泌，而选择性COX-2抑制剂celebrcx则可在一定时间和剂量范围内抑制VEGF的表达。     

罗非昔布抑制胰腺癌细胞ERK、AP-1信号转导通路

目的研究环氧合酶-2抑制剂-罗非昔布对胰腺癌细胞株BXPC-3增殖的信号转导作用的影响.方法用免疫组化法检测裸小鼠胰腺癌移植瘤中c-Fos的表达,免疫印迹法检测BXPC-3中c-Fos、ERK蛋白的改变,采用EMSA技术检测罗非昔布对胰腺癌细胞AP-1活化的影响.结果罗非昔布可抑制裸小鼠胰腺癌移植瘤c-Fos的表达.随着罗非昔布浓度的增加,胰腺癌细胞中c-Fos、ERK蛋白逐渐下降.EMSA分析显示,20%胎牛血清能刺激胰腺癌细胞BXPC-3中AP-1的活化增加,罗非昔布能抑制这种刺激作用.结论罗非昔布可通过抑制胰腺癌细胞ERK、AP-1信号转导通路,抑制胰腺癌细胞增殖.     

AFP对裸鼠肝癌移植瘤生长的促进作用及对血管形成相关因子的影响

目的:探讨AFP对肝癌移植瘤生长及血管生成调节因子表达的影响。方法:采用pEGFP-N1-AFP和pEGFP-N1质粒分别转染SMMC-7721细胞构建SMMC-7721/AFP和SMMC-7721/CON细胞,将裸鼠分为实验组和对照组,分别于裸鼠皮下接种SMMC-7721/AFP和SMMC-7721/CON,从而建立人肝癌移植瘤模型,动态观测裸鼠肿瘤体积和质量变化;取肿瘤组织用实时定量RT-PCR和Western blot检测组织中的HOXA7、eIF4E、VEGFA和FGF2表达。结果:构建SMMC-7721/AFP和SMMC-7721/CON细胞,并将其接种到裸鼠皮下成功建立肝癌移植瘤模型。与对照组比较,实验组移植瘤体积与质量显著增高,成瘤后第12天,实验组移植瘤体积和质量分别为（307.71±47.63）mm3和（20.243±0.411）g,差异均具有显著性（P=0.012,P=0.04）。实时定量RT-PCR结果显示AFP过表达提高了肝癌移植瘤细胞HOXA7、eIF4E和FGF2 mRNA表达水平,分别为2.488±1.155、23.828±2.465和4.407±1.164,与对照组相比增高程度具有显著性差异,但VEGFA mRNA表达未见显著增强。Western blot结果显示:SMMC-7721/AFP较SMMC-7721/CON细胞显著提高HOXA7蛋白表达水平,但对FGF2和VEGFA无显著影响。结论:AFP基因转染可明显促进裸鼠肝癌移植瘤的生长,该作用可能与其促进肿瘤血管形成因子在mRNA水平的调控有关。     

舒林酸对胃癌种植瘤的抑制作用及血管形成的影响

背景与目的:观察舒林酸的体内抗胃癌生长作用,并探讨舒林酸与胃癌血管生成的关系及其作用机制.材料与方法:建立人胃癌细胞BGC-823裸鼠种植瘤模型,随机分成舒林酸治疗组(12 mg kg)、舒林酸预防组(8 mg kg)、维生素C对照组(Vit C 20 mg k)和空白对照组(生理盐水),共4组,给予舒林酸干预;用免疫组化检测胃癌移植瘤中COX-2、VEGF的表达和微血管密度(MVD值);用TUNEL法检测凋亡.结果:舒林酸抑制胃癌种植瘤生长,舒林酸治疗组和舒林酸预防组的肿瘤体积从第2周开始明显小于对照组(P<0.05),直到第35 d实验结束时舒林酸组与2个对照组相比,种植瘤体积均保持被明显抑制,差异均具有统计学意义(P<0.05).肿瘤组织的凋亡指数:舒林酸治疗组为11.6,舒林酸预防组为10.4,维生素c对照组为3.5,空白对照组为3.1,舒林酸组高于对照组(P<0.05);MVD值:舒林酸治疗组为5.4,舒林酸预防组为9.0,维生素C对照组为19.6,空白对照组为20.7,舒林酸组显著低于对照组(P<0.01).免疫组化结果:舒林酸组肿瘤组织COX-2蛋白和VEGF蛋白的阳性表达率均低于对照组(P<0.05).结论:舒林酸在体内的抗胃癌效应显著,其机制可能涉及抑制胃癌细胞增殖,促进细胞凋亡及减少肿瘤新生血管的生成.     

小干扰RNA对人胰腺癌细胞移植瘤血管生成的影响

目的研究小干扰RNA(small interfering RNA,siRNA)抑制血管内皮生长因子(vascular endothelial growth factor,VEGF)的表达对裸鼠皮下人胰腺癌PANC-1细胞移植瘤血管生成的影响。方法构建人胰腺癌PANC-1细胞40只裸鼠皮下移植瘤模型,随机分为4组。两组针对VEGF的siRNA真核表达载体(PU-VEGF-siRNA1,PU-VEGF-siRNA2)通过脂质体法行瘤内和瘤周注射;注射空质粒组作为实验对照组;未注射组作为空白对照组。注射1次/3天,共10次,末次注射3天后,剥离瘤体,免疫组化染色法观察VEGF阳性染色及微血管参数,RT-PCR检测瘤组织VEGF-mRNA表达。结果 PU-VEGFsiRNA2组移植瘤VEGF-mRNA及转染PU-VEGF-siRNA后肿瘤组织微血管密度(MVD)表达均较空质粒组及空白对照组低(P0.05)。而PU-VEGF-siRNA1组未发现差别(P0.05)。结论 siRNA能在体内抑制胰腺癌VEGF表达,抑制肿瘤血管生成。     

塞来昔布诱导人胃癌细胞凋亡抑制新生血管形成

目的 探讨环氧合酶2(COX-2)抑制剂塞来昔布对人胃癌细胞增殖和新生血管形成的抑制作用.方法 将59例胃癌患者随机分为试验组(37例)和对照组(22例),试验组术前给予常规剂量塞来昔布,共7d,然后行手术治疗;对照组行单纯手术治疗.免疫组化法检测胃癌组织中COX-2和血管内皮生长因子(VEGF)的表达及微血管密度(MVD),DNA末端原位标记染色法检测胃癌细胞凋亡.以20例健康人作为正常对照.结果 试验组胃癌细胞凋亡率为7.1%±1.0%,显著高于对照组(6.2%±0.9%,P<0.05).试验组和对照组中,COX-2阳性表达分别为16例(43.2%)和17例(77.3%),VEGF阳性表达分别为17例(45.9%)和16例(72.7%),差异均有统计学意义(P<0.05).试验组MVD为30.48±5.02,显著低于对照组(38.98±4.58,P<0.05).结论 塞来昔布可诱导人胃癌细胞凋亡,抑制胃癌新生血管形成.     

NK4基因转染对裸鼠胰腺癌移植瘤生长的影响

背景与目的:NK4不仅是肝细胞生长因子的拮抗剂,而且是血管形成的抑制剂。研究已经证实NK4可以抑制肿瘤的生长和转移,但有关其在胰腺癌中的作用,目前少见文献报道。为此,本研究旨在探讨NK4基因在裸鼠体内的抗胰腺癌作用及其可能的机制。方法:建立裸鼠胰腺癌皮下移植瘤模型,构建NK4基因真核细胞表达载体并转染入瘤体内,转染前后称其体重、瘤重和测肿瘤体积,采用免疫组织化学和脱氧核糖核酸末端转移酶介导的缺口末端标记技术对裸鼠胰腺癌组织中的凋亡细胞、增殖抗原和微血管密度进行观察和比较。结果:4周后,NK4转染组裸鼠移植瘤体积为(1.39±0.33)cm3,明显小于对照组和空载体组[(2.06±0.55)cm3和(1.90±0.36)cm3,P<0.01];其瘤重为(1.30±0.81)g,也显著低于对照组和空载体组[(3.45±1.88)g和(3.14±1.51)g,P<0.01],抑瘤率为62.29%。NK4转染组肿瘤细胞的凋亡指数为9.34±0.91,显著高于对照组和空载体组(4.13±0.79和3.94±1.03,P<0.001);而NK4转染组肿瘤细胞的增殖指数为53.88±4.30,与对照组间和空载体组比较无显著性差异(56.24±4.03和54.33±5.41,P>0.05);NK4转染组肿瘤组织的微血管密度为(12.24±4.63),明显低于对照组和空载体组(20.13±7.00和19.70±6.15,P<0.05)。结论:转染NK4基因可显著抑制裸鼠胰腺癌移植瘤的生长,其作用机制可能是通过抑制肿瘤新生血管的形成,促进肿瘤细胞凋亡。     

TL对人胰腺癌细胞裸鼠移植瘤的治疗作用及抑制血管生成的研究

目的：探讨雷公藤内酯醇（TL）对人胰腺癌细胞SW1990移植瘤的生长及新生血管生成的抑制作用。方法：通过人胰腺癌裸鼠皮下移植实验，观察不同剂量TL对移植瘤生长抑制作用；应用免疫组化和RT-PCR研究裸鼠移植瘤组织VEGF表达变化，计算肿瘤组织微血管密度（MVD）。结果：各实验组（TL0．125、0．25和0．5mg·^-1kg·day^-1）抑瘤率分别达到66．16％、78．14％和89．92％，与对照组相比，肿瘤生长明显受抑，并具有剂量和时间依赖性。对照组和各实验纽瘤组织MVD分别为36．25±8．64、22．75±6．67、17．65±7．11和9．87±3．34（P〈0．01）；TL抑制移植瘤VEGF基因和蛋白表达．且VEGF基因下调与MVD的减少具有相关性（r=0．7424，P〈0．01）．结论：TL具有显著的抗胰腺癌移植瘤作用．其机制可能与抑制肿瘤新生血管生成有关。     

Iressa抑制高转移性人肝癌LCI-D20原位移植瘤的血管形成

[目的]探讨Iressa对人高转移肝癌模型LCI-D20血管形成的抑制作用。[方法]12只原位移植LCI-D20肿瘤裸鼠分为采用空白对照组（A组）及Iressa治疗组（B组），用药28d后处死裸鼠．测量肿瘤质量，检测肿瘤组织微血管密度（MVD）。[结果]对照组肿瘤负衙平均为2．01／g，MVD平均为39．57个／HP；治疗组平均肿瘤负荷及平均MVD为1．18g、14．10个／HP，与对照组比较差异有显著性（P〈0．05）。[结论]Iressa有抑制肝癌血管形成及肿瘤生长的活性。     

Endostatin对结肠癌生长和转移抑制作用的实验研究

背景与目的:结肠癌的生长、转移是血管生成依赖性的,血管生成抑制剂有望通过抑制肿瘤血管生成,诱导结肠癌细胞凋亡,有效地抑制结直肠癌的生长和转移。肿瘤的抗血管生成治疗对选择手术时机和方式、制定综合治疗方案,提高结肠癌患者5年生存率都具有重要意义。本实验研究血管生成抑制因子Endostatin对结肠癌生长和转移的抑制作用,并探讨其对结肠癌细胞凋亡的影响。方法:采用人结肠腺癌细胞株SW1116完整组织块裸鼠原位种植,建立类似于临床的结肠癌转移裸鼠模型。种植后第1周开始皮下注射Endostatin,每天一次,剂量为0mg/kg(对照组)、5mg/kg、10mg/kg、20mg/kg(治疗组),共用6周。种植后第7周处死动物,测量原位肿瘤瘤重、抑瘤率、肿瘤微血管密度(intratumoralmicrovesseldensity,MVD)、肿瘤细胞凋亡指数(apoptoticindex,AI),观察肿瘤细胞腹膜、肝、其他脏器转移及腹水情况。结果:Endostatin剂量为0mg/kg、5mg/kg、10mg/kg、20mg/kg时,原位肿瘤瘤重分别为(1.31±0.36)g、(0.42±0.17)g、(0.21±0.09)g、(0.13±0.05)g;抑瘤率分别为0%、67.9%、84.0%、90.1%;MVD分别为(12.8±4.1)、(5.9±2.5)、(2.2±1.4)、(0.74±O.3);AI分别为(3.87±2.61)%、(6.89±5.18)%、(13.24±4.76)%、(20.97±9.04)%;腹膜转移率分别为9     

As2O3 对ACC-2移植瘤血管生成的影响

目的研究三氧化二砷（As2O3）对人腺样囊性癌ACC-2裸鼠移植瘤生长及血管生成的抑制作用,探讨其抗肿瘤的作用机制。方法通过建立ACC-2裸鼠移植瘤模型,将28只荷瘤鼠随机分为4组：阴性对照组（生理盐水即NS）、阳性对照组[5-Fu10mg／（kg·d）]、低剂量组[As2O3．5mg／（kg·d）]、高剂量组[As2O3 5．0mg／（kg·d）]。连续经腹腔注射用药10天。测量肿瘤的体积和重量,采用HE染色光镜观察,免疫组织化学法检测VEGF、MVD的表达并进行统计学分析。结果高、低剂量As2O3组移植瘤的瘤体积、瘤重均低于两对照组（Ns组和5-Fu组）,且高剂量As2O3组抑瘤最明显,瘤体积抑制率为52．17％,瘤重抑制率为56．04％（P〈0．01）。在移植瘤表面,与两对照组相比,高、低剂量As2O3组血管密度减小,管径变细。高、低剂量As2O3组抑制移植瘤VEGF的表达、降低MVD值,高剂量As2O3组抑制作用最明显。与两对照组比较以及高、低剂量As2O3组之间比较差异均有统计学意义（P〈0．01）。结论As2O3对人腺样囊性癌ACC-2裸鼠移植瘤及血管生成有明显抑制作用,其作用机制可能为降低VEGF表达及MVD值,此抑制作用与剂量有关。     

Blockade of the chemokine receptor CXCR2 inhibits pancreatic cancer cell-induced angiogenesis

A central feature of all solid tumor growth is the presence of neovascularization. The CXC chemokines GRO-gamma/CXCL3, ENA-78/CXCL5, and IL-8/CXCL8 have profound angiogenic potential mediated through the CXCR2 receptor. The aim of the present study was to evaluate the expression of the angiogenic chemokines in three human pancreatic cancer cell lines and to determine the role of these proteins in pancreatic cancer angiogenesis. Secreted CXC protein levels in the supernatant of the cell lines were analyzed by ELISA. A rat corneal micropocket model was used to determine the angiogenic potential of these secreted CXC chemokines in vivo. ELISA confirmed expression of all three tested CXC chemokines in the supernatant of two cell lines. In the corneal micropocket assay, neovascularization was induced using pelleted supernatant of all three-cell lines. Using an anti-CXCR2 antibody, neovascularization was significantly inhibited in the high expressing BxPC-3 cell line samples. In addition, the expression of ENA-78/CXCL5 and IL-8/CXCL8 has been evaluated in human pancreatic cancer tissue samples by using immunohistochemistry in order to further investigate the potential role of CXC chemokines in pancreatic cancer angiogenesis and tumorigenesis.     

Combination therapy of human pancreatic cancer implanted in nude mice by oral fluoropyrimidine anticancer agent (S-1) with interferon-alpha

Purpose: We evaluated the antitumor and antiangiogenic activities of human natural interferon-alpha (IFN-α) alone or in combination with S-1 against human pancreatic cancer cells. Methods: Three days after the subcutaneous (s.c.) implantation of tumor cells, mice (n = 12) were received s.c. injection with IFN-α alone (10,000 U six times a week), oral administration with S-1 alone (8 mg/kg six times a week), or both with IFN-α and S-1 (8, 10, 12 mg/kg six times a week). Results: Administration of IFN-α in combination with S-1 significantly decreased progressive growth and angiogenesis of human pancreatic cancer cells. The combination therapy produced more significant inhibition in expression of the representative proangiogenic molecules, vascular endothelial growth factor and basic fibroblast growth factor than individual treatment either IFN-α or S-1 alone did. These treatments also decreased the staining of proliferating cell nuclear antigen, induced apoptosis and decreased microvessel density. In order to better understand the precise molecular mechanisms by which IFN-α and S-1 exert its effects, we have utilized cDNA microarray including 124 known genes to determine the gene expression profile altered by IFN-α and S-1 treatment. We found a total of seven genes which showed a twofold change after IFN-α and S-1 treatment in addition to VEGF, bFGF, CD31, MMP-2, MMP-7 and MMP-9. Among these genes, we found down-regulation of six genes and up-regulation of one gene, which are related to angiogenesis, tumor cell invasion and metastasis. Conclusions: These data suggest that administration of IFN-α in combination with S-1 may provide a novel and effective approach to the treatment of human pancreatic cancer.     

Antitumor effect of an anti-endothelial cell monoclonal antibody BVE-1 on solid tumor xenograft in nude mice

Thedevelopmentofnewbloodvesselsisimportantintumorgrowthandmetastasis.Targetingvascularendothelialcellstoinhibitangiogenesisoroccludethebloodvessels,blockthepassageofbloodelementstotumorcells,resultinginirreversibletumorcellsdeath,maybeanovelstrategyoftumortherapy.BurrowsFJ,etal.wasthefirstwhoproposedtheapproachofantibodyderivestargetingvascularendothelialcellsinsolidtumors.HedevelopedananimalmodelexpressingtumorvascularendotheliumbytransfectionofthetumorcellwithIFN-ygene.Whenanti-MHC-IIimm…     

Rottlerin suppresses growth of human pancreatic tumors in nude mice,and pancreatic cancer cells isolated from Kras mice

The purpose of the study was to examine the molecular mechanisms by which rottlerin inhibited growth of human pancreatic tumors in Balb C nude mice, and pancreatic cancer cells isolated from Kras^G12D mice. AsPC-1 cells were injected subcutaneously into Balb c nude mice, and tumor-bearing mice were treated with rottlerin. Cell proliferation and apoptosis were measured by Ki67 and TUNEL staining, respectively. The expression of components of Akt, Notch, and Sonic Hedgehog (Shh) pathways were measured by the immunohistochemistry, Western blot analysis, and/or q-RT-PCR. The effects of rottlerin on pancreatic cancer cells isolated from Kras^G12D mice were also examined. Rottlerin-treated mice showed a significant inhibition in tumor growth which was associated with suppression of cell proliferation, activation of capase-3 and cleavage of PARP. Rottlerin inhibited the expression of Bcl-2, cyclin D1, CDK2 and CDK6, and induced the expression of Bax in tumor tissues compared to untreated control. Rottlerin inhibited the markers of angiogenesis (Cox-2, VEGF, VEGFR, and IL-8), and metastasis (MMP-2 and MMP-9), thus blocking production of tumorigenic mediators in tumor microenvironment. Rottlerin also inhibited epithelial–mesenchymal transition by up-regulating E-cadherin and inhibiting the expression of Slug and Snail. Furthermore, rottlerin treatment of xenografted tumors or pancreatic cancer cells isolated from Kras^G12D mice showed a significant inhibition in Akt, Shh and Notch pathways compared to control groups. These data suggest that rottlerin can inhibit pancreatic cancer growth by suppressing multiple signaling pathways which are constitutively active in pancreatic cancer. Taken together, our data show that the rottlerin induces apoptosis and inhibits pancreatic cancer growth by targeting Akt, Notch and Shh signaling pathways, and provide a new therapeutic approach with translational potential for humans.     

Ellagic acid inhibits human pancreatic cancer growth in Balb c nude mice

Ellagic acid (EA) is a polyphenol found in several plants and fruits. The objectives of this study were to examine the molecular mechanisms by which EA inhibits pancreatic cancer growth in Balb C nude mice. PANC-1 cells were injected subcutaneously into Balb c nude mice, and tumor-bearing mice were treated with EA. The expression of Akt, Shh and Notch and their target gene products were measured by the immunohistochemistry and Western blot analysis. Treatment of PANC-1 xenografted mice with EA resulted in significant inhibition in tumor growth which was associated with suppression of cell proliferation and caspase-3 activation, and induction of PARP cleavage. EA inhibited the expression of Bcl-2, cyclin D1, CDK2, and CDK6, and induced the expression of Bax in tumor tissues compared to untreated control group. EA inhibited the markers of angiogenesis (COX-2, HIF1α, VEGF, VEGFR, IL-6 and IL-8), and metastasis (MMP-2 and MMP-9) in tumor tissues. Furthermore, treatment of mice with EA caused a significant inhibition in phospho-Akt, Gli1, Gli2, Notch1, Notch3, and Hey1. EA also reversed epithelial to mesenchymal transition by up-regulating E-cadherin and inhibiting the expression of Snail, MMP-2 and MMP-9. These data suggest that EA can inhibit pancreatic cancer growth, angiogenesis and metastasis by suppressing Akt, Shh and Notch pathways. In view of the fact that EA could effectively inhibit human pancreatic cancer growth by suppressing Akt, Shh and Notch pathways, our findings suggest that the use of EA would be beneficial for the management of pancreatic cancer.     

miR-486-5p对裸鼠胃癌移植瘤生长的抑制作用

目的:探讨miR-486-5P对裸鼠皮下人胃癌移植瘤生长的影响及其可能的作用机制.方法:建立胃癌SGC-7901细胞裸鼠皮下移植瘤模型,经miR-486-5P过表达质粒处理后,观察裸鼠皮下移植瘤生长情况,采用Western blotting及免疫组织化学法检测miR-486-5p靶基因神经纤毛蛋白-2(NRP2)的表达水平.结果:成功构建胃癌SGC-7901细胞裸鼠皮下移植瘤模型;实验组移植瘤内miR-486-5p的表达水平明显高于对照组(P＜0.05),miR-486-5p可明显抑制裸鼠皮下胃癌移植瘤的生长;与阴性及空白对照组相比,实验组平均瘤体质量明显下降[(0.404±0.080) vs (0.748±0.122)、(0.788±0.176)g,均P＜0.05];移植瘤平均体积明显减小[(0.333 ±0.039) vs (0.597 ±0.175)、(0.594±0.216)cm3,均P＜0.05],实验组的抑瘤率达46.99％;实验组经miR-486-5p过表达质粒处理后,免疫组化检测结果显示,NRP2蛋白主要定位于胃癌细胞质内,呈棕黄色颗粒;实验组NRP2蛋白的IHS得分显著低于阴性及空白对照组[(2.2±0.84) vs (6.4±0.89),(6.2±1.48),均P＜0.01];阴性对照组与空白对照组的得分差异无统计学意义(P＞0.05);Western blotting检测结果显示,实验组移植瘤组织中NRP2蛋白的相对表达量显著低于阴性及空白对照组[(0.04±0.006) vs (0.70 ±0.03),(0.68±0.02),P＜0.01].阴性和空白对照组间的IHS得分值、抑瘤率及NRP2蛋白表达水平的差异均无统计学意义(P＞0.05).结论:miR-486-5p可明显抑制裸鼠皮下胃癌SGC-7901细胞移植瘤的生长,其作用机制可能与抑制NRP2的表达有关.