Serum midkine depends on lymph node involvement and correlates with circulating VEGF-C in oesophageal squamous cell carcinoma

Lymph node metastasis (LNM) is a key factor for selection of treatment method and patients' prognosis in oesophageal squamous cell carcinoma (ESCC). However, no biomarkers able to support the clinical detection of LNM have been reported. Recently, vascular endothelial growth factor C (VEGF-C) was found to be a more accurate marker of LNM in lung cancer than computed tomography. Midkine is a multifunctional cytokine involved in cancer development. We investigated circulating midkine levels in ESCC patients (n=73) compared with those in healthy subjects (n=42) with double-antibody-sandwich indirect enzyme-linked immunosorbent assay (DASI-ELISA). We found that midkine was elevated in ESCC and involved in metastatic disease. Serum midkine (sMK) was a good marker of LNM, evaluated both clinically and pathologically, as revealed by ROC analysis. It also correlated with serum levels of VEGF-C. The increase of sMK was related to cancer cells, although a weak correlation was observed between sMK and platelet and leucocyte counts.     

Serum midkine depends on lymph node involvement and correlates with circulating VEGF-C in oesophageal squamous cell carcinoma

Lymph node metastasis (LNM) is a key factor for selection of treatment method and patients’ prognosis in oesophageal squamous cell carcinoma (ESCC). However, no biomarkers able to support the clinical detection of LNM have been reported. Recently, vascular endothelial growth factor C (VEGF-C) was found to be a more accurate marker of LNM in lung cancer than computed tomography. Midkine is a multifunctional cytokine involved in cancer development. We investigated circulating midkine levels in ESCC patients (n=73) compared with those in healthy subjects (n=42) with double-antibody-sandwich indirect enzyme-linked immunosorbent assay (DASI-ELISA). We found that midkine was elevated in ESCC and involved in metastatic disease. Serum midkine (sMK) was a good marker of LNM, evaluated both clinically and pathologically, as revealed by ROC analysis. It also correlated with serum levels of VEGF-C. The increase of sMK was related to cancer cells, although a weak correlation was observed between sMK and platelet and leucocyte counts.     

A potential role for the endothelin ET A receptor in salt-sensitive hypertension of the proANP gene-disrupted mouse

We have previously shown that the partial disruption of the gene for atrial natriuretic peptide (ANP) results in a salt-sensitive phenotype. The present study examined the possibility that alterations in either the ANP natriuretic pathway or endothelin (ET) system in the kidney of the salt-challenged ANP +/− mouse was responsible for its salt-sensitive phenotype. Plasma ANP levels and renal cGMP activity were increased in response to a salt load in both ANP +/+ and +/− mice. However, the mRNA expression of proANP was found to be increased only in the ANP +/− kidney along with its guanylyl cyclase-linked receptor, NPRA; the upregulation of NPRA mRNA was limited to the renal medulla. This suggests that the renal ANP pathway remains capable of responding to a salt load in the ANP +/− animal, but may be compensating for other dysfunctional pathways. We also report a significant increase in renal ET-1 mRNA and ET_A receptor protein expression in medulla and cortex of the salt-treated, ANP +/− mouse, but not its wild-type counterpart. In fact, ET_A expression decreased in the renal cortex of the ANP +/+ salt-treated animal. The ET_B receptor expression was not affected by diet in either genotype. We hypothesize that the salt-sensitive hypertension in the ANP +/− mouse is exacerbated, and possibly driven by the vasoconstrictive effects resulting from an upregulated ET-1/ET_A pathway.     

藏药红景天减弱高原肺动脉高压大鼠肺小血管病理变化和血管内皮生长因子的增高

本研究旨在观察藏药红景天对高原自然环境下建立的肺动脉高压大鼠模型中肺血管重构和血管内皮生长因子(vascu-1ar endothelial growth factor,VEGF)表达的影响,探讨其对高原肺动脉高压的防治作用与机制.健康雄性Wistar大鼠50只,随机分为平原对照组、高原10天组、高原30天组、红景天10...     

匹伐他汀对Klotho基因敲除杂合子小鼠血管新生的促进作用

目的：探讨匹伐他汀对Klotho基因敲除杂合子小鼠血管新生的促进作用及其作用机制。方法：建立Klotho基因敲除杂合子小鼠（hetero kl＋／-）和同窝出生野生型小鼠（wild kl＋／＋）下肢缺血模型并分为4组：①hetero正常组;②hetero匹伐他汀组;③wild正常组;④wild匹伐他汀组。使用激光多普勒血流测定仪测定klotho（kl＋／-,kl＋／＋）小鼠投药前、下肢缺血手术后双下肢血流。免疫荧光组化SP法计数Klotho（kl＋／-,kl＋／＋）小鼠缺血肢毛细血管数。免疫酶组化直接法计数Klotho（kl＋／-,kl＋／＋）小鼠缺血肢磷酸化Akt阳性细胞数。蛋白印迹杂交方法检测Klotho（kl＋／-）小鼠缺血肢VEGF蛋白表达。结果：匹伐他汀使Klotho（kl＋／-,kl＋／＋）小鼠术后缺血肢血流恢复明显,缺血肢与非缺血肢血流面积比明显增加;匹伐他汀使Klotho（kl＋／-、kl＋／＋）小鼠缺血肢毛细血管密度增加、p-Akt阳性细胞数明显增加;匹伐他汀使Klotho（kl＋／-）缺血肢VEGF蛋白表达增强。结论：匹伐他汀有促进Klotho基因敲除杂合子小鼠血管新生的作用。其作用机制可能是通过VEGF—p—Akt—NO径路实现的。     

VEGF-C 在口腔鳞状细胞癌中的表达及其意义

目的:检测血管内皮生长因子-C(VEGF-C)在口腔鳞状细胞癌(鳞癌)和癌旁组织中的表达情况,探讨VEGF-C在口腔鳞癌的增殖、浸润和淋巴转移中的作用。方法:采用免疫组化方法检测60例口腔鳞癌病人癌组织和癌旁组织中VEGF-C的表达,应用图像分析系统进行分析,用Spearman相关分析研究其与病变部位、肿瘤大小、病理分级、临床分期及颈淋巴结转移之间的关系。结果:口腔鳞癌组织VEGF-C的表达明显高于癌旁组织(u=7.747,P<0.01),其表达强度与临床分期及淋巴结转移密切相关(r=0.564、0.706,P<0.05),与病变部位、大小、病理分级无关。结论:口腔鳞癌细胞分泌VEGF-C诱导癌周淋巴管增生扩张是发生区域淋巴结转移的重要因素之一,VEGF-C有望作为早期临床判断和预测颈淋巴结转移的指标之一。     

Elevation of circulating interleukin-8 is related to lymph node and distant metastases in esophageal squamous cell carcinomas--implication for clinical evaluation of cancer patient

The presence of lymph node metastasis (LNM) is an important factor in clinical evaluation of esophageal cancer patients. Biological markers able to support detection of metastatic lymph nodes are sought after. Interleukin-8 (IL-8) is overexpressed by many cancers and involved in cancer dissemination. We investigated the relationship between circulating IL-8 and clinicopathological features of esophageal squamous cell carcinoma (ESCC), and evaluated the diagnostic potential of IL-8, with reference to the key angiogenic and lymphangiogenic factors: vascular endothelial growth factors A and C (VEGF-A and VEGF-C). We found elevated IL-8 levels in ESCC patients, correlated with tumor size and cancer dissemination, especially LNM. Circulating IL-8 correlated with lymphangiogenic VEGF-C rather then angiogenic VEGF-A. The association weakened in metastatic cancers, suggesting divergent mechanism of IL-8 involvement in the dissemination process. The cytokine levels correlated with platelets and neutrophils, pointing at these cells as possible sources of circulating IL-8. We demonstrated IL-8 that positively correlated with inflammation status of ESCC patients. Circulating IL-8 was a better indicator of ESCC dissemination than VEGF-A or VEGF-C. Yet, the detection rates were not satisfactory enough to allow for the recommendation of IL-8 determination as an adjunct to the clinical evaluation of lymph node involvement in ESCC patients.     

Cross‐talk between the VEGF‐A and HGF signalling pathways in endothelial cells

Background information. Endothelial cells play a major role in angiogenesis, the process by which new blood vessels arise from a pre‐existing vascular bed. VEGF‐A (vascular endothelial growth factor‐A) is a key regulator of angiogenesis during both development and in adults. HGF (hepatocyte growth factor) is a pleiotropic cytokine that may promote VEGF‐A‐driven angiogenesis, although the signalling mechanisms underlying this co‐operation are not completely understood. Results. We analysed the effects of the combination of VEGF‐A and HGF on the activation of VEGFR‐2 (VEGF receptor‐2) and c‐met receptors, and on the stimulation of downstream signalling pathways in endothelial cells. We found that VEGFR‐2 and c‐met do not physically associate and do not transphosphorylate each other, suggesting that co‐operation involves signalling events more distal from receptor activation. We demonstrate that the VEGF isoform VEGF‐A₁₆₅ and HGF stimulate a similar set of MAPKs (mitogen‐activated protein kinases), although the kinetics and strengths of the activation differ depending on the growth factor and pathway. An enhanced activation of the signalling was observed when endothelial cells were stimulated by the combination of VEGF‐A₁₆₅ and HGF. Moreover, the combination of VEGF‐A and HGF results in a statistically significant synergistic activation of ERK1/2 (extracellular‐signal‐regulated kinase 1/2) and p38 kinases. We demonstrated that VEGF‐A₁₆₅ and HGF activate FAK (focal adhesion kinase) with different kinetics and stimulate the recruitment of phosphorylated FAK to different subsets of focal adhesions. VEGF‐A₁₆₅ and HGF regulate distinct morphogenic aspects of the cytoskeletal remodelling that are associated with the preferential activation of Rho or Rac respectively, and induce structurally distinct vascular‐like patterns in vitro in a Rho‐ or Rac‐dependent manner. Conclusions. Under angiogenic conditions, combining VEGF‐A with HGF can promote neovascularization by enhancing intracellular signalling and allowing more finely regulated control of the signalling molecules involved in the regulation of the cytoskeleton and cellular migration and morphogenesis.     

血管内皮生长因子受体-2所介导信号通路的研究进展

血管新生是许多生理和病理进程发生的重要机理．在生物体内,血管新生需经过多步精细调控历程,现有研究表明,血管内皮生长因子(VEGF)及其受体蛋白酪氨酸激酶,尤其是血管内皮生长因子受体-2(VEGFR-2)所介导的信号级联通路是其中关键性的调节途径．VEGF/VEGFR-2所介导的信号级联通路可以调控血管内皮细胞的增殖、迁移、存活和通透性的改变,促进血管的新生．VEGF与VEGFR-2的胞外区特异性结合后,引起受体的二聚化和自身的交互磷酸化,使胞内特定的酪氨酸残基磷酸化．下游信号蛋白可以通过其Src同源结构域-2(SH2)与VEGFR-2结合,随后激活下游的效应蛋白,调控内皮细胞的生物学活性．此外,VEGF/VEGFR-2信号通路还可以下调树突细胞(DC)的活性．对VEGF/VEGFR-2信号通路作用的深入了解,将有助于新药的研发．     

Rapamycin inhibits the invasive ability of thyroid cancer cells by down‐regulating the expression of VEGF‐C in vitro

The aim of this study was to observe the effects of rapamycin on proliferation, apoptosis and invasion of SW579 in vitro. The proliferation and apoptosis of SW579 cells were detected by methyl thiazolyl tetrazolium and flow cytometry. Transwell assay was used to observe the changes of invasive ability of SW579 cells after being treated with rapamycin. The effects of rapamycin on the expression of mammalian target of rapamycin (mTOR) signalling and vascular endothelial growth factor C (VEGF‐C) were observed by Western blot. The inhibition and apoptosis rates increased obviously when the concentration of rapamycin was 20 nm. When the rapamycin concentration was 10 nm, the invasive ability of SW579 cells changed significantly than when it was 5 nm. Our data showed that when the concentrations of rapamycin were over 20 nm, the expression of mTOR and p70S6K decreased significantly, and the expression of PTEN increased notably. There were no remarkable variations observed when we detected the expression of Akt. We found the expression of VEGF‐C was high in SW579 cells and decreased slightly when the cells were treated with 5 nm rapamycin. When the concentration of rapamycin was over 5 nm, significant changes were observed. Rapamycin could inhibit the proliferation and induce the apoptosis of human thyroid cancer cells in vitro by mTOR inhibition. No obvious changes observed in the expression of AKT indicated that there might be a feedback loop effect by the mTOR inhibition induced by rapamycin. Rapamycin could inhibit the invasive ability of SW579 cells by down‐regulating the expression of VEGF‐C. Copyright © 2012 John Wiley & Sons, Ltd.     

Chrysin ameliorates ANTU‐induced pulmonary edema and pulmonary arterial hypertension via modulation of VEGF and eNOs

Alpha‐naphthylthiourea (ANTU), a rodenticide induces lung toxicity. Chrysin a flavonoid possesses antioxidant, anti‐inflammatory, and antihypertensive potential. The aim of this study was to evaluate the efficacy of chrysin against ANTU‐induced pulmonary edema (PE) and pulmonary arterial hypertension (PAH) in laboratory rats. Sprague‐Dawley rats were used to induce PE (ANTU, 10 mg/kg, ip) and PAH (ANTU, 5 mg/kg, ip, 4 weeks). Animals were treated with chrysin (10, 20, and 40 mg/kg) and various biochemical, molecular, and histological parameters were evaluated. Acute administration of ANTU induces PE revealed by significant (P < 0.05) increase in relative lung weight, pleural effusion volume, lung edema, bronchoalveolar lavage fluid cell counts, total protein, 5‐hydroxytryptamine (5‐HT), lactate dehydrogenase (LDH), and γ‐glutamyl transferase (GGT), whereas pretreatment with chrysin (20 and 40 mg/kg, ip) significantly (P < 0.05) attenuated these ANTU‐induced biochemical and histological alterations. Repeated administration of ANTU caused induction of PAH evaluated by significant (P < 0.05) alterations in electrocardiographic, hemodynamic changes, and left ventricular function, whereas chrysin (20 and 40 mg/kg, p.o.) treatment significantly (P < 0.05) attenuated these alterations. ANTU‐induced hematological and serum biochemical (aspartate transaminase, alanine transaminase, LDH, and creatinine kinase MB) alterations were significantly (P < 0.05) inhibited by chrysin. It also significantly (P < 0.05) decreased elevated levels of oxido‐nitrosative stress in the right ventricle (RV) and lung. Chrysin significantly (P < 0.05) attenuated downregulated endothelial nitric oxide synthase and upregulated vascular endothelial growth factor messenger RNA and protein expressions both in the RV and pulmonary artery. Chrysin inhibited ANTU‐induced PE and PAH via modulation of inflammatory responses (5‐HT, LDH, and GGT), oxido‐nitrosative stress, and VEGF and eNOs levels.     

Erythropoietin attenuates the sequels of ischaemic spinal cord injury with enhanced recruitment of CD34+ cells in mice

Erythropoietin has been shown to promote tissue regeneration after ischaemic injury in various organs. Here, we investigated whether Erythropoietin could ameliorate ischaemic spinal cord injury in the mouse and sought an underlying mechanism. Spinal cord ischaemia was developed by cross-clamping the descending thoracic aorta for 7 or 9 min. in mice. Erythropoietin (5000 IU/kg) or saline was administrated 30 min. before aortic cross-clamping. Neurological function was assessed using the paralysis score for 7 days after the operation. Spinal cords were histologically evaluated 2 and 7 days after the operation. Immunohistochemistry was used to detect CD34(+) cells and the expression of brain-derived neurotrophic factor and vascular endothelial growth factor. Each mouse exhibited either mildly impaired function or complete paralysis at day 2. Erythropoietin-treated mice with complete paralysis demonstrated significant improvement of neurological function between day 2 and 7, compared to saline-treated mice with complete paralysis. Motor neurons in erythropoietin-treated mice were more preserved at day 7 than those in saline-treated mice with complete paralysis. CD34(+) cells in the lumbar spinal cord of erythropoietin-treated mice were more abundant at day 2 than those of saline-treated mice. Brain-derived neurotrophic factor and vascular endothelial growth factor were markedly expressed in lumbar spinal cords in erythropoietin-treated mice at day 7. Erythropoietin demonstrated neuroprotective effects in the ischaemic spinal cord, improving neurological function and attenuating motor neuron loss. These effects may have been mediated by recruited CD34(+) cells, and enhanced expression of brain-derived neurotrophic factor and vascular endothelial growth factor.     

Changes in VEGF expression and DNA synthesis in hepatocytes from hepatectomized and tumour‐bearing mice

Transplanted tumours could modify the intensity and temporal distribution of the cellular proliferation in normal cell populations, and partial hepatectomy alters the serum concentrations of substances involved in cellular proliferation, leading to the compensatory liver hyperplasia. The following experiments were designed in order to study the SI (S‐phase index) and VEGF (vascular endothelial growth factor) expression in regenerating liver (after partial hepatectomy) of adult male mice bearing a hepatocellular carcinoma, throughout one complete circadian cycle. We used adult male C3H/S‐strain mice. After an appropriate period of synchronization, the C3H/S‐histocompatible ES2a hepatocellular carcinoma was grafted into the subcutaneous tissue of each animal's flank. To determine the index of SI and VEGF expression of hepatocytes, we used immunohistochemistry. The animals were divided into two experimental groups: Group I, control, hepatectomized animals; Group II, hepatectomized tumour‐bearing animals. The statistical analysis of SI and VEGF expression was performed using Anova and Tukey as a postcomparison test. The results show that in the second group, the curve of SI changes the time points for maximum and minimum activity, and the peak of VEGF expression appears before the first group. In conclusion, in the hepatectomized mice, the increases of hepatic proliferation, measured by the SI index, may produce a rise in VEGF expression with the object of generating a vascular network for hepatic regeneration. Lastly, as we have mentioned, in hepatectomized and tumour‐bearing mice, the peak of VEGF expression appears before the one of DNA synthesis.     

逍遥丸合六味地黄丸对原因不明月经过少子宫内膜细胞ER、VEGF和KDR表达影响

探讨逍遥丸合六味地黄丸治疗原因不明月经过少的机理.原代培养原因不明月经过少病人的子宫内膜,采用免疫细胞化学进行细胞鉴定.空白对照组,高剂量组,中剂量组,低剂量组,雌激素组.免疫蛋白质斑迹法观察子宫内膜细胞的雌激素受体(ER)、血管内皮生长因子(VEGF)及其受体(KDR)表达改变.逍遥丸合六味地黄丸能增强子宫内膜细胞的ER、VGER和KDR表达.逍遥丸合六味地黄丸可能通过提高子宫内膜组织中ER、VEGF和KDR治疗原因不明月经过少.     

Jumping the barrier: VE-cadherin, VEGF and other angiogenic modifiers in cancer

The endothelial barrier controls the passage of fluids, nutrients and cells through the vascular wall. This physiological function is closely related to developmental and adult angiogenesis, blood pressure control, as well as immune responses. Moreover, cancer progression is frequently characterized by disorganized and leaky blood vessels. In this context, vascular permeability drives tumour-induced angiogenesis, blood flow disturbances, inflammatory cell infiltration and tumour cell extravasation. Although various molecules have been implicated, the vascular endothelial adhesion molecule, VE-cadherin (vascular endothelial cadherin), has emerged as a critical player involved in maintaining endothelial barrier integrity and homoeostasis. Indeed, VE-cadherin coordinates the endothelial cell-cell junctions through its adhesive and signalling properties. Of note, many angiogenic and inflammatory mediators released into the tumour microenvironment influence VE-cadherin behaviour. Therefore restoring VE-cadherin function could be one very promising target for vascular normalization in cancer therapies. In this review, we will mainly focus on recent discoveries concerning the molecular mechanisms involved in modulating VE-cadherin plasticity in cancer.     

ILK和VEGF165b在人肾癌组织中的表达及意义

探讨整合素连接激酶(ILK)和血管内皮生长因子165b(VEGF165b)在人肾癌组织中的表达及临床意义.利用免疫组织化学S-P法检测35例肾癌组织和25例正常肾组织中ILK和VEGF165b蛋白的表达,并与肾癌临床分期进行比较.35例肾癌组织中,ILK表达率为82.9%(29/35),VEGF165b表达率为17.1%(6/35);而25例正常肾组织中ILK表达率为28.0%(7/25),VEGF165b表达率为96.0%(24/25).肾癌中ILK的表达与VEGF165b的表达呈负相关(P<0.01);ILK与VEGF165b的表达均与肾癌的临床分期有关.ILK在肾癌组织中异常活性表达,VEGF165b在肾癌组织的表达明显降低,二者表达成负相关,与肾癌的发生、发展密切相关.     

Cardiac overexpression of human VEGF165 by recombinant Semliki Forest virus leads to adverse effects in pressure-induced heart failure

Semliki Forest virus (SFV) is an efficient vector for cardiac gene delivery. The relatively short transgene expression induced by SFV seems appropriate for angiogenic gene therapy. We tested the effects of SFV expressing vascular endothelial growth factor (VEGF) on cardiac angiogenesis and heart failure in the mRen2 transgenic rat. Six-week-old mRen2 rats received SFV-VEGF or control virus (n=7 each) administered intracoronarily. Twelve days after transfection, cardiac capillary density and function were assessed. Capillary density in cardiac regions where SFV expression was highest had decreased by 20% in the SFV-VEGF-treated group. The decrease in capillary density was accompanied by impaired systolic function as illustrated by increased endsystolic volumes and a 34% decrease in cardiac output. We conclude that the time frame of SFV expression is sufficient to induce structural alterations, but that VEGF in mRen2 transgenic rats did not elicit the expected angiogenic effect. Rather, capillary density was decreased and subsequently cardiac function was impaired. This paradoxical finding is possibly related to the pathophysiology associated with this model and warrants caution if one is to pursue VEGF-mediated, angiogenic therapy before proceeding to a clinical setting. (Neth Heart J 2007;15:335-41.)