Expression of thymidine kinase mediated by a novel non-viral delivery system under the control of vascular endothelial growth factor receptor 2 promoter selectively kills human umbilical vein endothelial cells

AIM: To investigate the killing efficiency of a recombinant plasmid containing a thymidine kinase (TK) domain insert driven by the vascular endothelial growth factor receptor 2 (VEGFR2) promoter (KDR) on vascular endothelial cells.METHODS: The KDR-TK fragment was extracted from pBluescript Ⅱ KDR-TK plasmid by enzymatic digestion with Xho I and Sal I. The enhanced green fluorescence protein (EGFP) carrier was extracted from pEGFP by the same procedure. The KDR-TK was inserted into the pEGFP carrier to construct pEGFP-KDR-TK. Using ultrasound irradiation and microbubble, pEGFP-KDR-TK was transferred into human umbilical vein endothelial cells (HUVECs). The transient infection rate was estimated by green fluorescent protein (GFP) expression. Transfected HUVECs, non-transfected HUVECs, and HepG2 cells were cultured in the presence of different concentrations of ganciclovir (GCV), and the killing efficacy of HSV-TK/GCV was analyzed by 3-[4, 5-dimethylthiazol-2-yl]-2, 5-diphenyl tetrazolium bromide (MTT) assay. RESULTS: The recombinant pEGFP-KDR-TK was successfully constructed by inserting the KDR-TK fragment into the pEGFP carrier. Transfected HUVECs showed cytoplasmic green fluorescence, and the transient transfection rate was about 20.3%. Pools of G418-resistant cells exhibited a higher sensitivity to theprodrug/GCV compared to non-transfected HUVECs or non-transfected HepG2 cells, respectively. CONCLUSION: KDR promoter and the suicide gene/prodrug system mediated by diagnostic ultrasound combined with microbubble can significantly kill HUVECs. Such therapy may present a novel and attractive approach to target gene therapy on tumor vessels.

Vascular endothelial growth factor/platelet-derived growth factor receptor pathway is involved in bone marrow mesenchymal stem cell differentiation and directional migration toward gliomas

BACKGROUND： Vascular endothelial growth factor （VEGF） induces bone marrow-derived mesenchymal stem cell （BMSC） differentiation into vascular endothelial-like cells and promotes BMSC migration toward gliomas. However, the molecular mechanisms by which VEGF induces BMSC differentiation and migration remain poorly understood. OBJECTIVE; To investigate the role of platelet-derived growth factor （PDGF） receptor （PDGFR） in BMSC differentiation and migration induced by VEGE DESIGN, TIME AND SETTING： A parallel, controlled, in vitro experiment was performed at the Molecular Neurobiology ＆ Neural Regeneration and Repairing Laboratory, Anhui Provincial Hospital of Anhui Medical University, China from June 2008 to March 2009. MATERIALS： U87 glioma cells were purchased from Shanghai Institutes for Biological Sciences; mouse anti-human PDGFR and VEGF receptor （VEGFR） monoclonal antibodies were purchased from Peprotech, USA. METHODS： Isolated BMSCs were precultured with neutralizing antibody for VEGFR-1, VEGFR-2, PDGFR-α, and PDGFR-β to block biological activity of related receptors, followed by induced differentiation with 50μg/L VEGF. BMSCs induced with 50μg/L VEGF alone served as the VEGF-induced group. The control group remained untreated. MAIN OUTCOME MEASURES： Cell surface markers were identified by flow cytometry; BMSC surface cytokine receptor expression was detected by reverse transcription-polymerase chain reaction; the Transwell model was used to observe cell migration. RESULTS： After blocking the PDGFR, VEGF did not induce BMSC cell surface marker CD-31 or von Willebrand factor （vWF） expression. However, inhibition with VEGF receptor blocking agents, VEGF induced BMSCs to express CD-31 and vWE Following inhibition of the PDGFR, the number of cells migrating through the polycarbonate membrane Transwell chamber was decreased, as well as the number of BMSCs migrating to glioma cells. However, through the use of VEGF receptor blocking agents, the number of migrating cells remained unchanged. VEGF preculture increased the number of BMSCs migrating to gliomas. CONCLUSION： VEGF interacts with PDGFRs on the BMSC surface to attract BMSC directional migration and induce BMSC differentiation. The VEGF/PDGFR pathway participates in BMSC directional migration to glioma. VEGF pretreatment increased efficiency of BMSC migration to glioma.

The effect of Chinese herbal medicine“heche assisted pregnancy recipe”on endometrial estrogen and progesterone receptor,proliferating cell nuclear antigen and vascular endothelial growth factor in the patients with infertility

Objectives:To investigate the effect of Chinese herbal medicine"heche assisted preg-nancy recipe (HCAPR)" on estrogen receptor(ER), progesterone receptor (PR), pro-lifierating cell nuclear antigen(PCNA) and vascular endothelial growth factor (VEGF)in endometrium of infertile women.Methods: The S-P immunohistochemical assay was used to observe expression ofER, PR , PCNA and VEGF in late proliferative phase before and after the HCAPR treat-ment.Results: After the treatment, the expression of ER,PR,PCNA and VEGF in nucleiof glandular epithelium and stromal cells was significantly stronger (all P＜0. 001) re-spectively than that before treatment , especially the expression of PCNA and VEGF.Conclusions: These results suggest that traditional Chinese medicine HCAPR oftonifying kidney and regulating menstruation increased the synthesis of ER,PR, PCNAand VEGF, which may promote normal growth and development of the endometrium ,improve the micro-environment of the endometrium, and enhance uterine receptivity.The evidence may provide theoretical basis for therapy infertility with Chinese herbalmedicine.

Influence of vascular endothelial growth factor and radiation on gap junctional intercellular communication in glioblastoma multiforme cell lines

Glioblastoma multiforme （GBM） is a highly aggressive glial brain tumor with an unfavorable prognosis despite all current therapies including surgery, radiation and chemotherapy. One characteristic of this tumor is a strong synthesis of vascular endothelial growth factor （VEGF）, an angiogenesis factor, followed by pronounced vascularization. VEGF became a target in the treatment of GBM, for example with bevacizumab or the tyrosine kinase inhibitor axitinib, which blocks VEGF receptors. To improve patients＇ prognosis, new targets in the treatment of GBM are under investigations. The role of gap junctions in GBM remains un- known, but some experimental therapies affect these intercellular channels to treat the tumor. Gap junctions are composed of connexins to allow the transport of small molecules between adjacent cells through gap junc- tional intercellular communication （GJIC）. Based on data derived from astrocytes in former studies, which show that VEGF is able to enhance GJIC, the current study analyzed the effects of VEGF, radiation therapy and VEGF receptor blockade by axitinib on GJIC in human GBM cell lines U-87 and U-251. While VEGF is able to induce GJIC in U-251 cells but not in U-87 cells, radiation enhances GJIC in both cell lines. VEGF reocptor blockade by axitinib diminishes radiation induced effects in U-251 partially, while increases GJIC in U-87 cells. Our data indicate that VEGF and radiation are both modifying components of GJ1C in pathologic brain tumor tissue.

Expression of vascular endothelial growth factor and its role in oncogenesis of human gastric carcinoma

AIM: To establish the role of vascular endothelial growth factor (VEGF) in the oncogenesis of human gastric carcinoma more directly. METHODS: The expression of VEGF and its receptor kinase-domain insert containing receptor (KDR) in human gastric cancer tissue were observed by immunohistochemical staining. VEGF levels were manipulated in human gastric cancer cell using eukaryotic expression constructs designed to express the complete VEGF(165) complimentary DNA in either the sense or antisense orientation. The biological changes of the cells were observed in which VEGF was up-regulated or down-regulated. RESULTS: VEGF-positive rate was 50%, and VEGF was mainly localized in the cytoplasm and membrane of the tumor cells, while KDR was mainly located in the membrane of vascular endothelial cells in gastric cancer tissues and peri-cancerous tissue. In 2 cases of 50 specimens, the gastric cancer cells expressed KDR, localized in both the cytoplasm and membrane. Introduction of VEGF(165) antisense into human gastric cancer cells (SGC-7901, immunofluorescence intensity, 31.6%)) resulted in a significant reduction in VEGF-specific messenger RNA and total and cell surface VEGF protein (immunofluorescence intensity, 8.9%) (P【0.05). Conversely, stable integration of VEGF(165) in the sense orientation resulted in an increase in cellular and cell surface VEGF (immunofluorescence intensity, 75.4%) (P【0.05). Lowered VEGF levels were associated with a marked decrease in the growth of nude mouse xenografted tumor (at 33 days postimplantation, tumor volume: 345.40 +/- 136.31 mm3)(P【0.05 vs control SGC-7901 group: 1534.40 +/- 362.88 mm3), whereas up-regulation of VEGF resulted in increased xenografted tumor size (at 33 days postimplantation, tumor volume: 2350.50 +/- 637.70 mm3) (P【0.05 vs control SGC-7901 group). CONCLUSION: This study provides direct evidence that VEGF plays an important role in the oncogenesis of human gastric cancer.

Small interfering RNA targeting PGC-1α inhibits VEGF expression and tube formation in human retinal vascular endothelial cells

AIMTo determine whether small interfering RNA (siRNA) of PGC-1α could inhibit vascular endothelial growth factor (VEGF) expression and tube formation in human retinal vascular endothelial cells (hRVECs).METHODShRVECs transfected with peroxisome proliferator-activated receptor-γ coactivator-1α (PGC-1α) siRNA were incubated for 24h and then placed into a normoxic (20%, O2) or hypoxic (1%, O2) environment for another 16h. PGC-1α mRNA and protein levels were detected by real-time PCR and Western blot. VEGF mRNA and protein levels were detected by real-time PCR and ELISA. Cell proliferation was evaluated by BrdU incorporation assay. Forty-eight hours after siRNA transfection, hRVECs were planted into Matrigel-coated plates and cultured under normoxic (20%, O2) or hypoxic (1%, O2) conditions for another 48h. The tube formation of hRVECs was observed under an optical microscope and quantified by counting the number of branch points and calculating the total tube length.RESULTSPGC-1α mRNA and protein levels were significantly reduced by PGC-1α siRNA, and VEGF mRNA and protein levels also decreased significantly. The percentage of BrdU-labeled cells in siPGC-1α groups were significantly decreased compared with control siRNA groups under normoxia and hypoxia in cell proliferation assay. In the tube formation assay, PGC-1α siRNA treated cells formed significantly fewer tubes.CONCLUSIONBlocking PGC-1α expression can inhibit VEGF expression in hRVECs and inhibit their ability to form tubes under both normoxic and hypoxic conditions.

^(125)I-labeled anti-b FGF monoclonal antibody inhibits growth of hepatocellular carcinoma

AIM: To investigate the inhibitory efficacy of 125I-labeled anti-basic fibroblast growth factor (bFGF) monoclonal antibody (mAb) in hepatocellular carcinoma (HCC).METHODS: bFGF mAb was prepared by using the 1G9B9 hybridoma cell line with hybridization technology and extracted from ascites fluid through a Protein G Sepharose affinity column. After labeling with 125I through the chloramine-T method, bFGF mAb was further purified by a Sephadex G-25 column. Gamma radiation counter GC-1200 detected radioactivity of 125I-bFGF mAb. The murine H22 HCC xenograft model was established and randomized to interventions with control (phosphate-buffered saline), 125I-bFGF mAb, 125I plus bFGF mAb, bFGF mAb, or 125I. The ratios of tumor inhibition were then calculated. Expression of bFGF, fibroblast growth factor receptor (FGFR), platelet-derived growth factor, and vascular endothelial growth factor (VEGF) mRNA was determined by quantitative reverse transcriptase real-time polymerase chain reaction.RESULTS: The purified bFGF mAb solution was 8.145 mg/mL with a titer of 1:2560000 and was stored at -20 °C. After coupling, 125I-bFGF mAb was used at a 1: 1280000 dilution, stored at 4 °C, and its specific radioactivity was 37 MBq/mg. The corresponding tumor weight in the control, 125I, bFGF mAb, 125I plus bFGF mAb, and 125I-bFGF mAb groups was 1.88 ± 0.25, 1.625 ± 0.21, 1.5 ± 0.18, 1.41 ± 0.16, and 0.98 ± 0.11 g, respectively. The tumor inhibition ratio in the 125I, bFGF mAb, 125I plus bFGF mAb, and 125I-bFGF mAb groups was 13.6%, 20.2%, 25.1%, and 47.9%, respectively. Growth of HCC xenografts was inhibited significantly more in the 125I-bFGF mAb group than in the other groups (P < 0.05). Expression of bFGF and FGFR mRNA in the 125I-bFGF mAb group was significantly decreased in comparison with other groups (P < 0.05). Groups under interventions revealed increased expression of VEGF mRNA (except for 125I group) compared with the control group.CONCLUSION: 125I-bFGF mAb inhibits growth of HCC xenografts. The coupling effect of 125I-bFGF mAb is more effective than the concomitant use of 125I and bFGF mAb.

Coexpression of vascular endothelial growth factor and its receptor KDR on gastric adenocarcinoma MGC803 cell line and stimulation of exogenous VEGF_(165) to MGC803 cells

Vascular endothelial growth factor (VEGF), also known as vascular permeability factor (VPF), is an angiogenic factor playing an important role in tumor growth. VEGF/VPF interacts with endothelial cells by way of two high-affinity receptor tyrosine kinases: flt-1 and KDR. The vast majority of published studies have described expression of the VPF/VEGF receptors specifically in endothelial cells. To elucidate the further function of VEGF in solid tumor development, the coex-pression of VEGF and KDR in gastric adenocarcinoma MGC803 cell lines was shown by reverse transcription polymerase chain reaction (RT-PCR). The MGC803 tumor cells could also be strongly immunostained for KDR by immunocytochemistry. It was further demonstrated that exogenous VEGF-165 can stimulate the MGC803 cell growth in both dose-dependent and time-dependent manners by 3H-thymidine incorporation. Furthermore, anti-VEGF165 monoclonal antibody and anti-KDR monoclonal antibody could dose-dependently block the VEGF166-induced cell growth. These results provided new evidence that VEGF could cause autocrine stimulation to the proliferation of gastric adenocarcinoma cells.

Effect of vascular endothelial growth factor and its receptor KDR on human airway smooth muscle cells proliferation

Airway remodeling with inflammatory cell infiltration, epithelial shedding, basement membrane thickening and increased mass of airway smooth muscle (ASM) is an important determinant of bronchial obstruction and hyperresponsiveness in asthma.^(1,2) Increased ASM mass is by far the most important abnormality responsible for excessive airway narrowing and compliance of the airway wall in asthma.^(1-3) ASM growth and proliferation in asthma is a complex phenomenon of which the underlying mechanisms are difficult to investigate in vivo. The increased amount of ASM in asthmatics is an indication of abnormal cell proliferation and growth, but little is known regarding the molecular mechanisms and factors that regulate ASM cell proliferation and growth in asthma.

靶向成纤维细胞生长因子受体1信号改善类风湿关节炎的骨破坏

背景:尽管科研人员已注意到成纤维细胞生长因子受体1在类风湿关节炎骨破坏中展现出巨大潜力,但尚未有学者对成纤维细胞生长因子受体1在类风湿关节炎骨破坏中的研究进展作全面综述。目的:通过查阅国内外相关文献,综合分析成纤维细胞生长因子受体1在类风湿关节炎骨破坏中的机制。方法:以“成纤维细胞生长因子受体1,类风湿关节炎,骨破坏,骨细胞,成骨细胞,破骨细胞,软骨细胞,巨噬细胞,滑膜成纤维细胞,T细胞,血管内皮细胞”为检索词检索中国知网数据库,以“fibroblast growth factor receptor 1,rheumatoid arthritis,bone destruction,osteocytes,osteoblasts,osteoclasts,chondrocytes,macrophages,synovial fibroblasts,T cells,endothelial cells”为检索词检索PubMed数据库,检索时间范围重点为1992年4月至2024年1月。通过阅读文献题目、摘要及全文,根据纳入与排除标准进行筛选,最后纳入82篇文献进行综述。结果与结论:成纤维细胞生长因子受体1广泛表达于骨组织相关细胞,包括骨细胞、成骨细胞、破骨细胞等,可以通过调控这些细胞的功能来影响骨重塑过程和维持骨稳态,促进类风湿关节炎骨破坏的发生和发展。成纤维细胞生长因子受体1还可以在滑膜成纤维细胞和巨噬细胞中参与炎症反应,在内皮细胞中调控滑膜血管生成,从多个方面促进骨破坏。成纤维细胞生长因子受体1可能是类风湿关节炎骨破坏的一个重要参与因素,为进一步研究类风湿关节炎治疗靶点提供依据。

GnRH Ⅱ与GnRH Ⅰ对子宫内膜异位症患者间质细胞分泌VEGF作用的比较(英文)

目的:测定GnRH Ⅱ与GnRH Ⅰ对子宫内膜异位症(EMs)患者离体培养子宫内膜间质细胞分泌血管内皮生长因子(VEGF)的影响,探讨GnRH Ⅱ对EMs患者可能的作用。方法:给予原代培养的EMs患者在位及异位子宫内膜间质细胞不同浓度的GnRH Ⅱ,GnRH Ⅰ类似物(戈舍瑞林,goserelin)处理,同时设对照组(不加GnRH),采用酶联免疫吸附法(ELⅠSA)测定培养液中VEGF浓度,并进行比较。结果:EMs患者离体培养的异位子宫内膜间质细胞经48 h培养,能分泌VEGF,分泌量与在位子宫内膜间质细胞的相近,两者比较差异无统计学意义(P>0.05)。不同浓度的GnRH Ⅱ对EMs患者离体培养的在位和异位子宫内膜间质细胞VEGF的分泌有明显的抑制作用,呈剂量依赖性(P<0.05),且较GnRH Ⅰ类似物(戈舍瑞林)的作用更强(P<0.05)。不同浓度的GnRH Ⅱ对EMs患者离体培养的异位子宫内膜间质细胞VEGF分泌的抑制作用明显强于在位(P<0.05)。结论:EMs患者的异位子宫内膜间质细胞具有分泌VEGF的功能,分泌量与在位子宫内膜的相近,这对EMs的形成和发展可能起重要作用。Gn-RH Ⅱ呈剂量依赖性地抑制异位内膜间质细胞分泌VEGF,其抑制作用明显强于在位,且GnRH Ⅱ明显强于GnRH Ⅰ,为寻找EMs抗血管形成方面的新药治疗提供了新的依据。

血管紧张素Ⅱ对外周血早期内皮祖细胞血管内皮生长因子表达的影响

目的观察血管紧张素Ⅱ对外周血早期内皮祖细胞血管内皮生长因子表达的影响。方法密度梯度离心法获取外周血单个核细胞,培养7天,收集贴壁细胞,随机分对照组、血管紧张素Ⅱ各浓度(10-3mol/L、10-5mol/L、10-7mol/L)组、血管紧张素Ⅱ+缬沙坦组、血管紧张素Ⅱ+PD123319组。多波长激光共聚焦显微镜鉴定FITC标记荆豆凝集素Ⅰ和D iI标记的乙酰化低密度脂蛋白双染色阳性为早期内皮祖细胞,流式细胞仪检测其表面标志进一步鉴定。酶联免疫吸附测定法对早期内皮祖细胞血管内皮生长因子的表达进行测定。结果血管紧张素Ⅱ呈浓度依赖方式上调早期内皮祖细胞血管内皮生长因子的表达,此作用可被缬沙坦显著抑制,使之接近正常水平,PD123319对此无明显作用。结论血管紧张素Ⅱ通过血管紧张素Ⅱ受体1介导上调早期内皮祖细胞的血管内皮生长因子的表达,并呈浓度依赖性,血管紧张素Ⅱ受体2不参与血管紧张素介导的血管内皮生长因子的分泌。

干扰素γ及血管紧张素Ⅱ对大鼠血管平滑肌细胞表达转化生长因子β1型受体的影响

转化生长因子β1(TGF β1)刺激细胞外基质 (ECM)生成 ,作者观察了血管紧张素Ⅱ(AngⅡ)及γ干扰素 (IFN γ)对大鼠血管平滑肌细胞 (VSMC)TGF βⅠ型受体(TβR I)表达的影响。培养大鼠VSMC ,以Western印迹法观察AngⅡ(10 -7mol/L)及IFN γ(5 0 0U/ml)作用 2 4h时对VSMCTβR I表达的影响。发现AngⅡ组TβR I表达明显高于对照组 (OD值 10 3 0 6± 9 34vs 6 2 2 4±4 39,P <0 0 1) ,IFN γ单独孵育对TβR I表达无影响 ,但可以明显抑制AngⅡ引起的TβR I表达 (OD值 81 37± 5 87)。表明AngⅡ刺激大鼠VSMCTβR I表达 ,IFN

人VEGF受体Ⅱ胞外Ⅲ区单克隆抗体研制与生物学活性测定

根据GenBank中发表的血管内皮细胞生长因子(VEGF)受体Ⅱ(KDR)基因序列,设计1对引物经RT-PCR从人脐静脉内皮细胞中克隆出KDR胞外Ⅲ区(KDRD3)编码序列,克隆入原核表达载体pGEX-6P1。重组质粒转化大肠杆菌BL21,用IPTG于37℃条件下诱导,经SDS-PAGE和Western blotting分析,表达出的融合蛋白大小为33.4 ku。利用纯化的重组融合蛋白免疫BALB/c小鼠,经淋巴细胞杂交瘤技术筛选获得2株KDR特异性单克隆抗体C4和F6。2株单抗均能特异性识别HUVEC细胞表达的天然KDR分子,HUVEC迁移抑制试验和HUVEC体外血管形成抑制试验结果显示,2株单抗均能特异性阻断血管内皮细胞生长因子与KDR分子的相互作用。结果表明:所获得的2株单抗对KDR具有良好的特异性和中和活性。

血管紧张素Ⅱ1型受体和血管紧张素转化酶在子宫内膜癌中的表达及相关性

目的检测血管紧张素Ⅱ1型受体(angiotensinⅡtype 1 receptor,AT1R)和血管紧张素转化酶(angiotensin converting en-zym e,ACE)在子宫内膜癌中的表达情况,探讨AT1R和ACE在子宫内膜癌患者预后判断和临床治疗等方面的价值。方法采用免疫组化EnV ision法染色,观察AT1R、ACE、血管内皮生长因子(vascu lar endothelial growth factor,VEGF)和微血管密度(m i-crovessel density,MVD)在18例正常子宫内膜、37例子宫内膜不典型增生和89例子宫内膜癌组织中的表达情况,分析AT1R和ACE与子宫内膜癌临床病理特征的关系,研究AT1R与VEGF和MVD的相关性。结果从正常子宫内膜上皮到子宫内膜不典型增生再到子宫内膜癌,AT1R的表达逐步上调,ACE的表达逐步下调,差异均有显著性。子宫内膜癌中AT1R的表达与患者年龄、临床分期、子宫肌壁浸润深度和淋巴结转移状况等有关,且AT1R的表达与VEGF的表达和MVD计数正相关,而ACE的表达仅与淋巴结转移状况有关。结论 AT1R可能参与子宫内膜癌的发生、发展,AT1R表达上调可促进癌细胞生长和新生血管形成,与子宫内膜癌的预后有关,AT1R可能成为治疗子宫内膜癌的新靶点。ACE在子宫内膜癌中的表达低于正常内膜组织,其具体机制有待于进一步研究。

GnRH-Ⅱ对子宫内膜异位症患者离体培养的子宫内膜间质细胞分泌VEGF的影响

目的:检测体外培养的子宫内膜异位症(endometriosis,EMs)患者在位和异位内膜间质细胞分泌的血管内皮生长因子(vascular endothelial growth factor,VEGF)的浓度,并观察不同浓度的II型促性腺激素释放激素(GnRH-Ⅱ)对在位和异位内膜间质细胞分泌VEGF的影响。方法:分别给予原代培养的EMs患者在位与异位子宫内膜间质细胞不同浓度(1×10-10～1×10-6mol/L)的GnRH-Ⅱ处理,不加GnRH-Ⅱ组作为对照,采用酶联免疫吸附法(ELISA)测定培养液中VEGF浓度并进行比较。结果:体外培养的EMs患者异位子宫内膜间质细胞分泌VEGF,培养48 h后分泌量与在位子宫内膜间质细胞比较差异无统计学意义(P(0.05)。1×10-10～1×10-6mol/L的GnRH-Ⅱ可呈浓度依赖性地抑制体外培养的在位和异位子宫内膜间质细胞分泌VEGF(P<0.01),且对异位子宫内膜间质细胞的抑制作用强于在位(P<0.01)。结论:EMs患者的异位子宫内膜间质细胞分泌VEGF的能力与在位子宫内膜的相近,这对EMs的形成和发展可能起重要作用。GnRH-Ⅱ对EMs患者体外培养的异位子宫内膜间质细胞VEGF的分泌有明显的抑制作用,且作用明显强于对在位内膜间质细胞的。

表皮生长因子受体在血管紧张素Ⅱ促血管平滑肌细胞增殖中的作用

目的探讨表皮生长因子受体在血管紧张素Ⅱ促大鼠血管平滑肌细胞增殖效应中的作用。方法用反义表皮生长因子受体寡核苷酸脂质体复合物转染SD大鼠血管平滑肌细胞,用逆转录聚合酶链反应、Western-Blot-ing分别检测转染后表皮生长因子受体mRNA及蛋白的表达情况,用氚标胸腺嘧啶脱氧核苷掺入实验检测血管平滑肌细胞的增殖情况。结果反义组大鼠血管平滑肌细胞表皮生长因子受体mRNA表达(0.18±0.03)较正义组(0.61±0.11)及对照组(0.66±0.09)明显减少(P<0.05),反义组大鼠血管平滑肌细胞表皮生长因子受体蛋白的表达(43.1±8.4)较正义组(92.6±10.5)及对照组(100.7±11.3)明显减少(P<0.05);反义组细胞的氚标胸腺嘧啶脱氧核苷掺入率(1055.1±95.7)较正义组(1882.4±129.7)及对照组(2013.3±121.3)明显降低(P<0.05)。结论表皮生长因子受体在血管紧张素Ⅱ促血管平滑肌细胞增殖中起重要作用。

血管紧张素Ⅱ对骨髓源内皮祖细胞增殖能力的影响及机制的探讨

目的研究血管紧张素Ⅱ(AngⅡ)对骨髓源内皮祖细胞(EPCs)增殖能力的影响,并探讨其可能机制。方法通过密度梯度离心法分离大鼠骨髓单个核细胞,进行诱导分化,培养7天获得EPCs。抗AC133与抗血管内皮生长因子受体对EPCs双标后进行激光共聚焦鉴定。收集贴壁细胞加入不同浓度AngⅡ(10-7mol/L、10-8mol/L、10-9mol/L)进行干预,MTT法观察EPCs增殖能力的变化,并利用RT-PCR法观察不同浓度AngⅡ干预及缬沙坦、蛋白激酶C(PKC)抑制剂预处理后EPCs的Flk-1 mRNA表达量的变化。结果在血管内皮生长因子(VEGF)存在的前提下,AngⅡ可以增强EPCs的增殖能力,并可以上调Flk-1 mRNA的表达。缬沙坦、抑制剂可以显著抑制AngⅡ的这种作用。结论AngⅡ可以通过1型受体、PKC通路上调EPCs的Flk-1,在VEGF的作用下促进其增殖,从而有助于血管新生。

血管内皮细胞生长因子受体Ⅱ抗体修饰的多西他赛脂质体的制备与药效学评价

目的制备由血管内皮细胞生长因子受体Ⅱ(vascular endothelial growth factor receptorⅡ,VEGFRⅡ)抗体修饰的多西他赛脂质体,并评价其对乳腺癌细胞MCF-7的体内外抗肿瘤效果。方法采用薄膜分散-挤出法制备多西他赛脂质体,再将血管内皮细胞生长因子受体Ⅱ-二硬脂酰基磷脂酰乙醇胺-聚乙二醇2000(VEGFRⅡ-distearoyl phosphothanolamine-polyethyleneglycol 2000,VEGFRⅡ-mPEG2000-DSPE)连接物与脂质体共同孵化制备成VEGFRⅡ修饰的介导多西他赛脂质体,通过透射电镜观察其微观形态,粒度分析仪测定其粒径分布和zeta电位,并考察了多西他赛脂质体和VEGFRⅡ抗体修饰的多西他赛脂质体的体外释药特性;比较了多西他赛脂质体和VEGFRⅡ抗体修饰的多西他赛脂质体在体外和体内对乳腺癌细胞MCF-7的抗肿瘤效果。结果在透射电镜下可观察到多西他赛脂质体和VEGFRⅡ抗体修饰的多西他赛脂质体均呈球状或类球状分布,平均粒径分别为(226.2±16.4)nm和(233.6±10.5)nm,多聚分散系数(PdI)分别为(0.186±0.012)和(0.179±0.009),zeta电位分别为(-9.7±0.6)mV和(-10.1±0.5)mV;多西他赛脂质体和VEGFRⅡ抗体修饰的多西他赛脂质体在pH 7.4磷酸缓冲液中释药均较为缓慢;在体外多西他赛脂质体和VEGFRⅡ抗体修饰的多西他赛脂质体均能够有效地抑制乳腺癌细胞MCF-7生长,而在裸鼠体内VEGFRⅡ修饰的多西他赛脂质体抑制乳腺癌细胞MCF-7生长速度显著高于多西他赛脂质体。结论本研究制备的VEGFRⅡ抗体修饰的多西他赛脂质体对乳腺癌细胞MCF-7具有较强的抑制活性,VEGFRⅡ抗体修饰的多西他赛脂质体具有潜在的临床应用价值,值得进一步研究。

核因子κB受体活化因子配体对血管紧张素Ⅱ诱导人肾小球足细胞分泌血管内皮细胞生长因子的影响

目的观察核因子κB受体活化因子配体(RANKL)对血管紧张素Ⅱ(AngⅡ)诱导的人肾足细胞分泌血管内皮细胞生长因子(VEGF)的影响,探究AngⅡ是否通过RANK/RANKL信号通路影响足细胞表达VEGF。方法以分化为树枝状的人肾足细胞为研究对象,以不同浓度(0、1、10、100 nmol/L)的AngⅡ处理,分别于不同时间(0、6、12、24 h)通过实时荧光定量PCR(RT-PCR)检测基因VEGF、RANK和RANKL的m RNA表达变化。然后以不同剂量的RANKL与100 nmol/L AngⅡ共同刺激足细胞24 h后,通过RT-PCR检测VEGF的m RNA表达变化,流式细胞术检测足细胞凋亡率变化。结果 AngⅡ呈剂量和时间依赖性地诱导足细胞表达VEGF、RANK和RANKL(P<0.05),而过量RANKL表现出剂量依赖性地阻断VEGF表达增高(P<0.05);与对照组比较,AngⅡ可以显著诱导足细胞凋亡(P<0.05),而RANKL可以抑制由AngⅡ诱导的足细胞凋亡(P<0.05)。结论 AngⅡ可能通过RANK/RANKL信号通路影响足细胞表达VEGF,RANKL通过反馈调节下调VEGF基因表达来抑制AngⅡ引起的足细胞凋亡,保护肾脏。