基因-病毒治疗系统AdHA对血管内皮细胞的抑制作用

目的:研究基因-病毒治疗系统AdHA对血管内皮细胞增殖的抑制作用,意在为卵巢癌抗血管生成治疗提供实验依据.方法:采用直接感染台盼蓝染色排除法、MTT实验检测血管抑素K1-5对血管内皮细胞增殖的抑制作用.结果:直接感染台盼蓝染色排除法及MTT法检测表明.携带血管抑素K1-5基因的腺病毒能显著抑制血管内皮细胞增生,并对其具有杀伤力.结论:血管抑素K1-5能明显抑制血管内皮细胞增殖,为进一步行体内实验,研究其对血管形成的抑制作用及卵巢癌抗血管生成基因治疗奠定了基础.     

内皮抑素对荷卵巢上皮性癌细胞系ES-2细胞裸鼠的抗血管生成作用

肿瘤的生长和转移与肿瘤区血管生长有密切关系，分期越晚，分化越差，肿瘤内血管密度（MVD）越高。抑制和破坏肿瘤区新牛血管的生长，阻断其血液供应导致肿瘤细胞坏死，并阻断其转移，成为治疗实体肿瘤的一种新途径。1997年，O’Reilly等体外实验发现，内皮抑素对牛毛细血管内皮细胞有特异的抑制增殖作用，而对非血管内皮细胞、平滑肌细胞等尢抑制作用；体内实验证明，内皮抑素可抑制鸡胚尿囊膜的毛细血管生长：近年来，已有数种作用机理不同的这类药物正在进行临床试验。目前，内皮抑素已应用于多种肿瘤的体内实验。本研究采用裸鼠移植瘤模型，观察内皮抑素对人卵巢上皮性癌（卵巢痛）移植瘤内肿瘤新生血管生成的抑制作用，现报道如下。     

内皮抑素在妇科肿瘤的研究进展

内皮抑素(endostatin)是在对小鼠血管内皮瘤(EOMA)细胞系的研究中发现的一种分子质量为20ku的蛋白，实验证明其对内皮细胞增殖有明显抑制作用，并通过抑制肿瘤相关的新生血管生成阻断肿瘤的血液供应，发挥抑制肿瘤生长作用，反复用药无任何毒副作用及耐药性。内皮抑素在妇科肿瘤中也有不同程度的表达，可作为妇科肿瘤早期诊断和治疗的新途径。     

格列卫对卵巢癌细胞COC1增殖及血管形成的影响

目的探讨格列卫(gleevec)对耐药卵巢癌细胞COC1增殖、顺铂敏感性和血管形成的影响,为临床应用格列卫治疗难治性卵巢癌提供实验依据。方法2006年9月至2007年5月于哈尔滨医科大学第一临床医学院采用四甲基偶氮唑蓝(MTT)法检测格列卫对细胞增殖的影响;采用ELISA法检测格列卫对COC1表达血管内皮细胞生长因子(VEGF)和内皮抑素(endostatin)的影响。结果格列卫对COC1细胞增殖的抑制作用表现出浓度依赖性,并显著提高了其对顺铂的敏感性;格列卫对COC1表达VEGF具有明显的抑制作用,格列卫对COC1表达内皮抑素具有明显促进作用,并呈浓度依赖性。结论格列卫能够抑制顺铂耐药卵巢癌细胞COC1的增殖,并显著增强其对顺铂的敏感性;格列卫对抑制肿瘤细胞产生VEGF具有明显的作用。     

内皮抑素在妇科肿瘤的研究进展

内皮抑素(endostatin)是在对小鼠血管内皮瘤(EOMA)细胞系的研究中发现的一种分子质量为20ku的蛋白,实验证明其对内皮细胞增殖有明显抑制作用,并通过抑制肿瘤相关的新生血管生成阻断肿瘤的血液供应,发挥抑制肿瘤生长作用,反复用药无任何毒副作用及耐药性.内皮抑素在妇科肿瘤中也有不同程度的表达,可作为妇科肿瘤早期诊断和治疗的新途径.     

M2型巨噬细胞调控卵巢癌腹膜内肿瘤血管生成的实验研究

目的:探讨上皮性卵巢癌(epithelial ovarian cancer,EOC)腹水中M2型巨噬细胞(M2 macrophage)调控腹膜内肿瘤血管生成的机制。方法:分离卵巢癌患者腹水中M2型巨噬细胞,体外无血清刺激后,收集上清M2作为条件培养基(M2 macrophage conditional medium,M2 CM),分别采用结晶紫染色实验、Transwell小室迁移实验和小管样结构形成实验,检测共培养刺激后其对人脐静脉血管内皮细胞系EA.hy926增殖、迁移以及小管样结构形成的影响;酶联免疫吸附试验(ELISA)检测刺激后EA.hy926细胞分泌促血管蛋白因子——白细胞介素8(IL-8)以及血管内皮生长因子(VEGF)的影响。结果:①经M2 CM刺激后,EA.hy926细胞的增殖能力提高,结晶紫染色后检测OD值为0.192 6±0.002(P<0.05)。②细胞迁移能力提高,迁移细胞数为84.81±2.04(P<0.001)。③M2 CM可显著促进内皮细胞小管样结构形成,与对照组差异有统计学意义(P<0.05)。④ELISA显示经M2 CM刺激后,EA.hy926分泌IL-8为(1 570.45±118.64)ng/L,VEGF分泌量也显著升高,为(502.21±133.61)ng/L,与对照组差异有统计学意义(P<0.001)。结论:EOC腹水中M2型巨噬细胞可能通过上调内皮细胞分泌VEGF及IL-8等促血管生成因子,增加血管内皮细胞增殖、迁移能力及小管样结构形成,从而促进卵巢癌腹膜内血管生成。     

血管内皮生长因子与卵巢癌

血管内皮生长因子(VEGF)能强烈促进血管内皮细胞有丝分裂、血管生成,增加血管通透性.VEGF及其受体在许多肿瘤包括卵巢肿瘤中表达,并在卵巢癌高表达,与卵巢癌的发生、发展、转移和预后等密切相关.通过检测、抑制VEGF,可能为卵巢癌的早期诊断、治疗开辟新的途径.     

S1P/S1PR对人卵巢癌SKOV3细胞的促血管生成作用的研究

目的：探究鞘氨醇-1-磷酸/鞘氨醇-1-磷酸受体（S1P/S1PR）对人卵巢癌SKOV3细胞促血管生成作用的影响和机制。方法：管腔形成实验探究S1P对人卵巢癌SKOV3细胞的促血管生成作用的影响;实时定量聚合酶链式反应（qRT-PCR）检测S1P处理后的人卵巢癌SKOV3细胞中血管生成因子白细胞介素8（IL-8）、IL-6、血管内皮生长因子（VEGF）的变化情况;设计合成小干扰RNA（siRNA）干扰序列基因沉默SKOV3细胞中S1PR1、S1PR2和S1PR3的表达,蛋白质印迹（Western-blot）和qRT-PCR检测SKOV3细胞中S1PR的下调结果;qRT-PCR检测S1PR对SKOV3细胞IL-8、IL-6、VEGF表达的影响。结果：管腔形成实验结果显示,S1P处理后的SKOV3细胞培养上清液重悬人脐静脉内皮细胞融合细胞（EA.hy926）,其管腔形成的数量多于对照组（t=3.667,P=0.021）,表明S1P促进了人卵巢癌细胞SKOV3的促血管形成能力。S1P处理后的SKOV3细胞中血管生成因子IL-8、IL-6、VEGF mRNA的表达水平较对照组升高,差异有统计学意义（均P＜0.05）。S1PR1和S1PR3基因沉默可显著降低SKOV3细胞中IL-8、IL-6、VEGF的mRNA表达水平,差异有统计学意义（均P＜0.05）,而S1PR2基因沉默后IL-8、IL-6、VEGF的mRNA变化不明显。结论：S1P通过S1PR1/3上调人卵巢癌SKOV3细胞中IL-8、IL-6、VEGF的表达,从而增强了SKOV3细胞的促血管生成作用,S1P/S1PR通路有望成为抑制卵巢癌生长的治疗新靶点。     

抗人血管内皮生长因子发夹状核酶基因抑制卵巢癌细胞血管内皮生长因子表达

目的 :研究抗血管内皮生长因子发夹状核酶基因对人卵巢癌细胞血管内皮生长因子 (VEGF)表达的抑制作用 ,探讨卵巢癌基因治疗的新途径。方法 :人卵巢癌细胞SKOV3高表达VEGF ,将抗血管内皮生长因子发夹状核酶基因真核表达载体 (pcDNA3 RZ)转染人卵巢癌细胞SKOV3,经G4 18筛选获得阳性细胞克隆 ,RNA斑点杂交检测核酶基因是否在细胞中表达。采用免疫组化、间接免疫荧光、激光共聚焦显微镜荧光定量法及流式细胞仪结合间接免疫荧光检测转染前后细胞VEGF的表达情况。结果 :转染pcDNA3 RZ组细胞VEGF表达明显降低。结论 :抗人VEGF发夹状核酶基因真核表达载体可有效抑制卵巢癌细胞SKOV3中VEGF的表达 ,有望成为治疗卵巢癌的一种新方法。     

内皮抑素真核表达载体对移植性卵巢癌的抑制作用

目的探讨脂质体介导的内皮抑素真核表达载体对裸鼠移植性卵巢癌的抑制作用。方法利用已构建的内皮抑素真核表达载体pVAX1sEn,在脂质体介导下转染卵巢癌细胞系3AO细胞,RTPCR技术检测3AO细胞中内皮抑素mRNA的表达,酶联免疫吸附实验(ELISA)法检测3AO细胞上清液中内皮抑素的水平,四甲基偶氮唑蓝(MTT)法检测3AO细胞上清液中的内皮抑素对脐静脉内皮细胞系ECV204细胞的抑制作用。将荷卵巢癌移植瘤裸鼠分为3组,pVAX1sEn治疗组、pVAX1对照组和生理盐水对照组,分别观察3组卵巢癌的生长情况。结果RTPCR技术检测结果显示,在610bp处有一内皮抑素mRNA的特异性条带;ELISA法检测结果显示,pVAX1sEn转染3AO细胞后其上清液中内皮抑素水平为(201±8)ng/ml;MTT法检测结果显示,pVAX1sEn转染3AO细胞后其上清液中的内皮抑素可有效抑制ECV204细胞的生长,最高抑制率为42%。pVAX1sEn治疗组肿瘤体积为(0.85±0.18)cm3,显著小于生理盐水对照组的(1.90±0.28)cm3和pVAX1对照组的(1.78±0.32)cm3(P<0.05)。肿瘤组织HE染色显示,pVAX1sEn治疗组肿瘤细胞坏死明显,而生理盐水对照组及pVAX1对照组肿瘤细胞生长旺盛。结论脂质体介导的pVAX1sEn瘤内注射可有效抑制卵巢癌移植瘤的生长。     

合体滋养细胞微粒对人脐静脉内皮细胞增殖和凋亡的影响

目的:检测合体滋养细胞微粒(STBM)对人脐静脉内皮细胞(HUVECs)增殖和凋亡的影响,探讨子痫前期可能的病因和发病机制。方法:选取2009年6月至10月在上海交通大学附属第六人民医院住院行选择性剖宫产的4例正常健康孕妇的胎盘,机械法体外制备STBM。STBM与HUVECs共培养,MTT法和流式细胞仪检测HUVECs的增殖和凋亡情况。结果:(1)STBM作用12h后,HUVECs悬浮细胞数增加,48h后可见大量悬浮细胞,细胞生存受到明显抑制;(2)30、90、150mg/L STBM作用48h后,内皮细胞增殖抑制率分别为(55.58±2.40)%、(67.94±1.93)%、(86.37±1.59)%,组间差异显著(P<0.01),呈剂量依赖性。(2)30、90、150mg/L STBM作用24h后,内皮细胞凋亡率分别为(17.39±1.11)%、(22.13±1.02)%、(30.42±1.98)%,组间差异显著(P<0.01),呈剂量依赖性。结论:STBM可抑制HUVECs细胞增殖,诱导细胞凋亡,提示其可能是子痫前期内皮细胞功能紊乱的原因。     

Hypoxia Enhances FGF2- and VEGF-Stimulated Human Placental Artery Endothelial Cell Proliferation: Roles of MEK1/2/ERK1/2 and PI3K/AKT1 Pathways

Placental development occurs under a low oxygen (2–8% O₂) environment, which is critical for placental development and angiogenesis. In this study, we examined if hypoxia affected fibroblast growth factor-2 (FGF2)- and vascular endothelial growth factor (VEGF)-stimulated cell proliferation via the mitogen-activated protein kinase kinase 1/2 (MEK1/2)/extracellular signal-regulated kinases 1/2 (ERK1/2) and phosphatidylinositol-3 kinase (PI3K)/v-akt murine thymomaviral oncogene homologue (AKT1) pathways in human placental artery endothelial (HPAE) cells. We observed that under normoxia (～20% O₂), FGF2 and VEGF dose-dependently stimulated cell proliferation. Hypoxia (3% O₂) significantly promoted FGF2- and VEGF-stimulated cell proliferation as compared to normoxia. Under both normoxia and hypoxia, FGF2 rapidly induced ERK1/2 and AKT1 phosphorylation, while VEGF-induced ERK1/2, but not AKT1 phosphorylation. However, hypoxia did not significantly alter FGF2- and VEGF-induced ERK1/2 and AKT1 phosphorylation as compared to normoxia. PD98059 (a MEK1/2 inhibitor) at 20 μM and LY294002 (a PI3K inhibitor) at 5 μM attenuated FGF2- and VEGF-induced phosphorylation of ERK1/2 and AKT1, respectively. PD98059, even at doses that drastically inhibited FGF2-induced ERK1/2 phosphorylation (20 μM) and caused cell loss (40 μM), did not affect FGF2-stimulated cell proliferation, which was confirmed by U0126 (another potent MEK1/2 inhibitor). PD98059, however, dose-dependently inhibited VEGF-stimulated cell proliferation. Conversely, LY294002 dose-dependently inhibited FGF2-, but not VEGF-stimulated cell proliferation. These data suggest that in the MEK1/2/ERK1/2 and PI3K/AKT1 pathways differentially mediate FGF2- and VEGF-stimulated HPAE cell proliferation. These results also indicate that hypoxia promotes FGF2- and VEGF-stimulated cell proliferation without further activation of the PI3K/AKT1 and MEK1/2/ERK1/2, respectively.     

Neutrophils infiltrating the endometrium express vascular endothelial growth factor: potential role in endometrial angiogenesis

OBJECTIVE(S): To identify leukocytes within the human endometrium expressing vascular endothelial growth factor (VEGF). DESIGN(S): Prospective cohort study. SETTING(S): Healthy volunteers in an academic research environment. PATIENTS(S): Twenty-one normal cycling women without abnormal menstrual bleeding or infertility. INTERVENTION(S): Endometrial tissue collection by Pipelle de Cornier aspiration. MAIN OUTCOME MEASURES(S): Histologic, immunohistochemical (CD3, CD34, CD56, CD68, neutrophil elastase, estrogen and P receptors, VEGF), and simultaneous double immunoenzymatic labeling analysis of VEGF-positive cells within the human endometrium. RESULT(S): Ten endometrial samples were obtained in the proliferative (cycle days 5-10) and 11 samples in the secretory phase (cycle days 15-26). Immunohistochemical analyses showed the expected distribution of the different leukocyte cell types. Besides epithelial and stromal endometrial cells, the predominant cells that stained for VEGF were neutrophil granulocytes. Neutrophils were more abundant in the secretory phase but they expressed neither estrogen-a nor P receptors. CONCLUSION(S): Neutrophil granulocytes infiltrating the human endometrium express VEGF and regulate cyclical endometrial vascular proliferation. Ovarian steroids indirectly influence neutrophil migration.     

HMGB1对子宫内膜异位症新生血管生成的潜在作用

新生血管生成是子宫内膜异位症（EMs）的重要发病机制之一。异常的血管增生为异位内膜组织的生长、浸润和转移提供有利的条件。高迁移率族蛋白B1（HMGB1）除了介导炎症反应外,近年研究发现其也可促进多种肿瘤的新生血管生成。研究发现,EMs患者体内HMGB1的表达明显升高,提示HMGB1可能参与EMs的发病机制。HMGB1可直接作用于血管内皮细胞,或激活巨噬细胞上调核因子κB（NF-κB）,促进血管内皮生长因子（VEGF）的合成和分泌,间接作用于内皮细胞,促进新生血管网的形成。此外,HMGB1还可通过上调成纤维细胞生长因子（FGF）的表达及提高整合素的活性和亲和力,促进内皮细胞的增殖和迁移;刺激血小板衍生生长因子（PDGF）的分泌,募集周细胞和平滑肌细胞,促进血管管状结构的形成;促进内皮细胞释放转录生长因子β（TGF-β）,推动血管管状结构的成熟。综述HMGB1参与调节EMs中新生血管生成的潜在作用机制,可为EMs的治疗提供新的靶点。     

2-Methoxyestradiol prevents monocyte adhesion to vascular endothelial cells via downregulation of VCAM-1 expression

2-Methoxyestradiol (2-ME) reduces atherosclerotic lesion formation. However, the underlying mechanisms remain largely unknown. In this work, we investigated the effect of 2-ME on monocyte adhesion to vascular endothelial cells. Lipopolysaccharides (LPS) greatly increased the attachment of monocyte onto cultured human umbilical vascular endothelial cells (HUVECs), which was inhibited by 2-ME in a dose- and time-dependent manner, or by the vascular cell adhesion protein-1 (VCAM-1) neutralizing antibody, suggesting that a functional releationship between 2-ME and VCAM-1 may exist. In accordance with this, treatment with 2-ME (10^?7–10^?5 M) for 6–48?h downregulated VCAM-1 protein expression. Meanwhile, the nuclear factor κB (NF-κB) p65 subunit activity and its nuclear translocation was inhibited by 2-ME in HUVECs. The PI3K inhibitor wortmannin or the specific Akt siRNA both inhibited the effects of 2-ME, suggesting that 2-ME inhibited p65 activity via PI3K/Akt signaling. In conclusion, 2-ME inhibits VCAM-1 expression and thus prevents monocyte adhesion to vascular endothelial cells via regulation of PI3K/Akt and NF-κB signaling. These findings will be helpful for better understanding the mechanisms through which 2-ME improves endothelial function.     

Intracavernous Delivery of Freshly Isolated Stromal Vascular Fraction Rescues Erectile Function by Enhancing Endothelial Regeneration in the Streptozotocin‐Induced Diabetic Mouse

IntroductionMen with diabetic erectile dysfunction (ED) often have severe endothelial dysfunction and respond poorly to oral phosphodiesterase‐5 inhibitors.AimTo examine whether and how freshly isolated stromal vascular fraction (SVF) promotes cavernous endothelial regeneration and restores erectile function in diabetic animals.MethodsEight‐week‐old C57BL/6J mice were used. Diabetes was induced by intraperitoneal injection of streptozotocin. SVF was isolated from epididymal adipose tissues of green fluorescence protein transgenic mice. At 8 weeks after the induction of diabetes, the animals were divided into six groups: controls, diabetic mice, and diabetic mice treated with a single intracavernous injection of phosphate‐buffered saline (PBS) or SVF (1 × 10⁴ cells, 1 × 10⁵ cells, or 2 × 10⁵ cells/20 µL, respectively).Main Outcome MeasuresTwo weeks later, erectile function was measured by cavernous nerve stimulation. The penis was stained with antibodies to CD31, CD34, phosphohistone H3, phospho‐endothelial nitric oxide synthase (eNOS), and vascular endothelial growth factor‐A (VEGF‐A). We also performed Western blot for phospho‐eNOS and eNOS, and determined cyclic guanosine monophosphate (cGMP) concentration in the corpus cavernosum tissue.ResultsSignificant improvement in erectile function was noted in diabetic mice treated with SVF at concentrations of 1 × 10⁵ and 2 × 10⁵ cells, which reached up to 82% of the control values. Local delivery of SVF significantly increased cavernous endothelial cell proliferation, eNOS phosphorylation, and cGMP expression compared with that in the untreated group and the PBS‐treated diabetic group. Intracavernous injection of SVF increased cavernous VEGF‐A expression and induced recruitment of CD34(+)CD31(?) progenitor cells. Some SVF underwent differentiation into cavernous endothelial cells. SVF‐induced promotion of cavernous angiogenesis and erectile function was abolished in the presence of VEGF‐Trap, a soluble VEGF‐A neutralizing antibody.ConclusionThe results support the concept of cavernous endothelial regeneration by use of SVF as a curative therapy for diabetic ED. Ryu J‐K, Tumurbaatar M, Jin H‐R, Kim WJ, Kwon M‐H, Piao S, Choi MJ, Yin GN, Song K‐M, Kang Y‐J, Koh YJ, Koh GY, and Suh J‐K. Intracavernous delivery of freshly isolated stromal vascular fraction rescues erectile function by enhancing endothelial regeneration in the streptozotocin‐induced diabetic mouse. J Sex Med 2012;9:3051–3065.     

Estradiol down-regulates MCP-1 expression in human coronary artery endothelial cells

OBJECTIVE: To determine whether estrogen down-regulates MCP-1 in vascular endothelial cells. DESIGN: A prospective comparative study. SETTING: Academic research environment. PATIENT(S): Human umbilical vein endothelial cells (n = 3) and human coronary artery endothelial cells (n = 3) obtained from females. INTERVENTION(S): Human umbilical vein endothelial cells (HUVEC) and human coronary artery endothelial cells (HCAEC) were grown to preconfluence. Then, they were treated with various concentrations of estradiol (10(-11) M to 10(-7) M) as well as raloxifene (10(-7) M) and tamoxifen (10(-7) M). MCP-1 in culture media was quantified using an enzyme-linked immunosorbent assay (ELISA). Cellular ribonucleic acid (RNA) was extracted and Northern blots were hybridized with an oligonucleotide probe complementary to a specific sequence of MCP-1 mRNA. MAIN OUTCOME MEASURE(S): MCP-1 protein and mRNA. RESULT(S): Estrogen treatment did not change MCP-1 expression in HUVEC. On the other hand, in HCAEC, estradiol induced a 30% decrease in mRNA expression and resulted in dose-dependent inhibition of MCP-1 production as detected by ELISA. Raloxifene and tamoxifen also resulted in inhibition of MCP-1 mRNA and protein expression. CONCLUSION(S): Our findings suggest that one of the mechanisms by which estrogen down-regulates atherosclerosis is by suppressing vascular MCP-1 expression, resulting in decreased macrophage recruitment.     

Expression and function of placenta growth factor: implications for abnormal placentation

OBJECTIVE: Essential requirements for successful gestation include the coordinated growth and differentiation of the placenta and the development of a functional placental vasculature. However, relatively little is known about factors that are responsible for regulating these functions. One angiogenic growth factor that might be involved in regulating both vascular endothelial cell and trophoblast function is placental growth factor (PGF). METHODS: Current published reports were surveyed and our own work was reviewed to highlight the expression, function, and potential significance of PGF at the human maternal-fetal interface. RESULTS: PGF is highly expressed in trophoblasts during normal pregnancy, and its expression is significantly decreased in preeclampsia, an obstetric complication presumed to be associated with placental bed hypoxia and ischemia. In agreement with this, in vitro trophoblast expression of PGF can be down-regulated by low oxygen tension. The cognate receptor for PGF, fms-like tyrosine kinase receptor, is expressed on trophoblasts as well as vascular endothelial cells, suggesting that it has autocrine and paracrine functions. Accordingly, PGF can regulate proliferation in first trimester trophoblasts, apoptosis in term trophoblasts, and it can directly or indirectly regulate vascular growth, maturation, and permeability. CONCLUSIONS: Many obstetric complications, most notably preeclampsia, are associated with aberrant trophoblast function and inadequate or dysfunctional vasculature within the developing placenta. The ability of PGF to influence trophoblast and vascular endothelial cells provides clear impetus for further studies to investigate the biological and clinical significance of PGF in normal and abnormal human pregnancies.     

Hypoxia activates the human placental vascular endothelial growth factor system in vitro and in vivo: up-regulation of vascular endothelial growth factor in clinically relevant hypoxic ischemia in birth asphyxia

OBJECTIVE: We investigated the influence of acute hypoxia on the placental vascular endothelial growth factor system in vitro and in vivo in acute birth asphyxia compared with pregnancies that were complicated by preeclampsia and with healthy control subjects. STUDY DESIGN: Messenger RNA levels for vascular endothelial growth factor, flt-1, and KDR were measured by TaqMan real-time polymerase chain reaction in human placental choriocarcinoma cells (BeWo) that were exposed to hypoxia (1% oxygen, 5% carbon dioxide, 94% nitrogen) and in placental tissue of neonates with birth asphyxia (n = 20), newborn infants of mothers with preeclampsia (n = 20), and gestational age-matched control subjects. Immunhistologically, placental vascular endothelial growth factor protein expression was compared among the groups. RESULTS: In BeWo cells, vascular endothelial growth factor, flt-1 and KDR messenger RNA increased in a time-dependent manner in response to hypoxia. In vivo, vascular endothelial growth factor/beta-actin and KDR/beta-actin messenger RNA were significantly higher in placental tissue of newborn infants with severe hypoxic-ischemic encephalopathy than with newborn infants with mild or no hypoxic-ischemic encephalopathy and control subjects. In chronic placental hypoxia (preeclampsia), vascular endothelial growth factor and both receptors were found to be up-regulated. Increased placental vascular endothelial growth factor expression was confirmed by immunohistologic examination. CONCLUSION: The vascular endothelial growth factor system is up-regulated in response to placental hypoxia and is assumed to be a potential early indicator of severe birth asphyxia.