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2.
Objective: To investigate the relationship between the expression of endothelial nitric oxide synthase (eNOS), vascular endothelial growth factor (VEGF) and angiogenesis in primary astrocytoma. Methods: Thirty-seven primary astrocytomas and 4 astrocytic hyperplasia samples were collected and divided into three groups according to histological grade. The expression of eNOS, VEGF and factorⅧrelated antigen (FⅧRAg) were assayed by immunohistochemistry. Microvascular density was assessed by FⅧRAg immunoreactivity. The intensity of immunoreactivity was graded according to the percentage of positive tumor cells. Results: No eNOS and VEGF were expressed in the astrocytes and vascular endothelium in astrocytic hyperplasia. The expression of eNOS or VEGF was light in low-grade astrocytoma and strong in glioblastoma. eNOS expression in astrocytoma was very positively correlated with VEGF. eNOS and VEGF expression in anaplastic astrocytoma was median in contrast to the low grade astrocytoma and glioblastoma. Lower microvascular density was found in low grade astrocytoma than that in higher grade malignant ones. The expressions of eNOS and VEGF were correlated with microvascular density and tumor malignancy. Conclusion: This finding suggests that eNOS and VEGF may have cooperative effect in tumor angiogenesis and play an important role in the pathogenesis of primary astrocytoma.  相似文献   

3.
Objective: To study the effects of the generation 4 polyamidoamine/vascular endothelial growth factor antisense oligodeoxynucleotide (G4PAMAMNEGFASODN) compound on the expressions of vascular endothelial growth factor (VEGF) and its mRNA of breast cancer cells and on the inhibition of vascular endothelial cells. Methods: We examined the morphology of G4PAMAM/VEGFASODN compound and its pH stability, in vitro transfection efficiency and toxicity, and the expressions of VEGF and its mRNA. Methyl thiazolyl tetrazolium assay was used to detect the inhibitory function of the compound on vascular endothelial cells. Results: The compound was about 10 nm in diameter and was homogeneously netlike. From pH 5 to 10, it showed quite a buffered ability. The 48-h transfection rate in the charge ratio of 1:40 was 98.76%, significantly higher than that of the liposome group (P<0.05). None of the transfection products showed obvious toxicity on the cells. The expressions of both VEGF protein and its mRNA after G4PAMAM/VEGFASODN transfection decreased markedly. Conclusion: With a low toxicity, high safety, and high transfection rate, G4PAMAMNEGFASODN could be a promising gene vector. Specifically, it inhibits VEGF gene expression efficiently, laying a basis for further in vivo animal studies.  相似文献   

4.
Angiogenesis is required for solid tumor growth and facilitates tumor progression and metastasis. The inhibition effects of O-（chloroacetyl-carbamoyl） fumagillol （TNP-470）, an angiogenesis inhibitor, and gemcitabine, a chemotherapeutic agent, on expression of growth factors were investigated using human pulmonary adenocarcinoma cell line, A549. The A549 cells were divided into four groups： control group, 10^-6 mg/ml gemcitabine treated group, 10^-4 mg/ml TNP-470 treated group and gemcitabine＋TNP-470 treated group. The mRNA and protein expression of vascular endothelial growth factor （VEGF） and its receptors, FMS-like tyrosine kinase-l （FLT-1） and kinase insert domain-containing receptor （KDR）, in different groups were measured. The growth of A549 cell cultured with gemcitabine or TNP-470 was inhibited in an almost dose-dependent manner. Although gemcitabine （10^-6 mg/ml） alone and TNP-470 （10^-4 mg/ml） alone had no effect on the mRNA and protein expression of VEGF and its receptors （FLT-1, KDR） in A549 cells compared to the control （P〉0.05）, 10^-6 mg/ml gemcitabine in combination with 10^-4 mg/ml TNP-470 had significant effect （P〈0.01）. Moreover, combination of the two drugs significantly inhibited the mRNA expression of VEGF, FLT-1 and KDR compared to either drug alone （P〈0.05）. This study suggests that combined treatment with TNP-470 plus gemcitabine may augment the antiangiogenic and antineoplastic effects in lung cancer cells in vitro.  相似文献   

5.
目的：探讨血管内皮生长因子（VEGF）在膀胱移行细胞癌中的表达及临床意义。方法：采用免疫组化、ELISA方法对45例膀胱移行细胞癌组织、血浆和10例正常膀胱黏膜组织、30例正常成人血浆中VEGF进行检测分析。结果：VEGF在膀胱移行细胞癌患者中呈高表达，且随分期、分级的增高而增高；膀胱癌手术前患者血浆中VEGF的浓度高于手术后。结论：1．VEGF的表达与膀胱移行细胞癌的病理分级、临床分期及生物学行为有密切关系；2．血浆中VEGF水平可有助于预测膀胱癌患者手术疗效。  相似文献   

6.
Homoharringtonine (HHT) has currently been used successfully in the treatment of acute and chronic myeloid leukemias and has been shown to induce apoptosis of different types of leukemic cells in vitro. Emerging evidence suggests that angiogenesis may play an important role in hematological malignancies, such as leukemia. How ever, whether HHT can relieve leukemia by anti-angiogenesis is still unknown. We investigated the anti-angiogenesis potential of HHT with the human umbilical vein endothelial cell line (ECV304) and leukemic cell line (K562) in vitro. Cellular proliferation was determined by MTT assay and apoptosis was analyzed by flow cytometry. The mRNA expression of vascular endothelial growth factor (VEGF) was assessed by RT-PCR and VEGF protein production was detected by Western blot. Inhibition of cell proliferation and induction of apoptosis by HHT were discovered in ECV304 cells, and appeared in a dose- and time-dependent manner. Also, treatment with HHT caused down-regulation of VEGF mRNA expression in K562 cells in similar dose- and time-dependent manner and inhibition of VEGF protein production in K562 cells in response to the enhancing concentration of HHT. The results demonstrated that HHT could also induce apoptosis in endothelium and down-regulate VEGF expression in K562 cells. In conclusion, we believe HHT has anti-angiogenesis potential and speculate that HHT might exert its anti-leukemia effects via reduction of angiogenesis.  相似文献   

7.
INTRODUCTION Homoharringtonine (HHT) is a cephalotoxin alkaloid with anti-leukemic activity and had been used successfully in the treatment of acute and chronic myeloid leukemias (O払rien et al., 1995; 1999; Feldman et al., 1992). The principal mecha-nism of action by HHT is the inhibition of protein synthesis in a dose- and time-dependent manner by binding to ribosome and inhibiting polypeptide chain elongation (Tujebajeva et al., 1989; Zhou et al., 1995). HHT had been shown to indu…  相似文献   

8.
Objective: Large segmental bone defect repair remains a clinical and scientific challenge with increasing interest focusing on combining gene transfection with tissue engineering techniques. The aim of this study is to investigate the effect of connective tissue growth factor (CTGF) on the proliferation and osteogenic differentiation of the bone marrow mesenchymal stem cells (MSCs). Methods: A CTGF-expressing plasmid (pCTGF) was constructed and transfected into MSCs. Then expressions of bone morphogenesis-related genes, proliferation rate, alkaline phosphatase activity, and mineralization were examined to evaluate the osteogenic potential of the CTGF gene-modified MSCs. Results: Overexpression of CTGF was confirmed in pCTGF-MSCs. pCTGF transfection significantly enhanced the proliferation rates of pCTGF-MSCs (P<0.05). CTGF induced a 7.5-fold increase in cell migration over control (P<0.05). pCTGF transfection enhanced the expression of bone matrix proteins, such as bone sialo-protein, osteocalcin, and collagen type I in MSCs. The levels of alkaline phosphatase (ALP) activities of pCTGF-MSCs at the 1st and 2nd weeks were 4.0- and 3.0-fold higher than those of MSCs cultured in OS-medium, significantly higher than those of mock-MSCs and normal control MSCs (P<0.05). Overexpression of CTGF in MSCs enhanced the capability to form mineralized nodules. Conclusion: Overexpression of CTGF could improve the osteogenic differentiation ability of MSCs, and the CTGF gene-modified MSCs are potential as novel cell resources of bone tissue engineering.  相似文献   

9.
采用大鼠大脑中动脉（MCAO）模型,肌肉内注射神经生长因子（NGF）,经过免疫组化和HE染色检测Sprague—Dawley（SD）大鼠脑缺血再灌注后HIF-1α（缺血诱导因子）及HSP70（热休克蛋白70）表达的变化及神经生长因子的影响。结果表明,肌肉注射神经生长因子对脑缺血再灌注有明显的保护作用,HIF—1α及HSP70表达增加可能是其机制之一。  相似文献   

10.
淋巴系统被认为是肿瘤转移的重要途径之一,所以通常情况下肿瘤引起的淋巴血管增生会降低肿瘤预后,治疗上也建议淋巴清扫。但是最新的研究显示,淋巴系统可能对肿瘤免疫治疗有促进作用。这篇综述的主要目的是对相关领域做一个简短总结,以期待将来有更多的研究来关注淋巴系统对肿瘤治疗的影响。文章首先介绍肿瘤淋巴血管增生和淋巴转移的分子机制,然后介绍淋巴系统在肿瘤免疫中的作用,最后利用最新研究来证明淋巴系统有增强肿瘤免疫治疗的作用。  相似文献   

11.
The aim of this study was to explore the protective effect of basic fibroblast growth factor (bFGF) on brain injury following global ischemia reperfusion and its mechanisms. Brain injury following global ischemia was induced by four vessels occlusion and systemic hypotension. Twenty-four rabbits were randomized into three groups: group A, only dissection of vessels; group B, intravenous infusion of normal saline after reperfusion for 6 h; group C, 30 μg/kg bFGF injected intravenously at the onset of reperfusion, then infused with 10 μg/(kg·h) for 6 h. Serum neuron specific enolase (NSE), S-100B, tumor necrosis factor-α(TNF-α), interleukin-1 (IL-1), interleukin-8 (IL-8) were measured before ischemia, 30 min after ischemia, 0.5, 1, 3, 6 h after reperfusion. Brain water content was determined and cerebral histopathological damages were compared. NSE and S-100B were increased 1 h after reperfusion and reached their peaks 6 h after reperfusion, but were much higher in group B than those in group C 3, 6 h after reperfusion. In groups B and C, TNF-a was increased after ischemia and IL-1 and IL-8 were increased significantly 0.5 h after reperfusion, then reached their peaks 6 h, 3 h, 6 h after reperfusion respectively. TNF-a and IL-8 at the time points of 1 h and 3 h and IL-1 at 3 h and 6 h in group C were correspondingly lower than those in group B. These indices in group A were nearly unchanged. There were less severe cerebral histopathological damages in group C compared with group B, but no difference in brain water content. It could be concluded that bFGF alleviates brain injury following global ischemia and reperfusion by down-regulating expression of inflammatory factors and inhibiting their activities.  相似文献   

12.
Objective:To investigate the relationship between the fatty acid-binding protein 4(FABP4)and colorectal cancer(CRC).Methods:Using an enzyme-linked immunosorbent assay(ELISA),we measured the expression of FABP4 in plasma of50 patients who underwent surgery for CRC from October 2017 to May 2018 and 50 healthy controls.The content of the visceral fat area(VFA)as seen with abdominal computed tomography(CT)scanning was measured by ImageJ software.The expression levels of FABP4,E-cadherin,and Snail proteins in CRC and adjacent tissues were determined by immunohistochemistry.Results:The mean concentration of plasma FABP4 of CRC patients was higher than that of the control group(22.46 vs.9.82 ng/m L;P<0.05).The concentration of plasma FABP4 was related to the tumor,node,metastatis(TNM)stage and lymph node metastasis and was independent of age,body mass index(BMI),tumor size and location,and the degree of differentiation of CRC.The concentration of plasma FABP4 was positively correlated with high VFA and lipoprotein-a(LPA)(P<0.05);but it was not correlated with total cholesterol(TG),total triglyceride(TC),low-density lipoprotein(LDL),high-density lipoprotein(HDL),or apolipoprotein AI(Apo-AI).The expression of FABP4 protein in CRC tissues was positively correlated with the degree of CRC differentiation,tumor stage,and lymph node metastasis.The level of FABP4 protein was negatively correlated with E-cadherin protein(r=-0.3292,P=0.0196)and positively correlated with Snail protein(r=0.5856,P<0.0001).Conclusions:High LPA and VFA were risk factors for increased plasma FABP4 in CRC patients.FABP4 protein was highly expressed in CRC tissues and associated with TNM stage,differentiation,and lymph node metastasis of CRC.The level of FABP4 in CRC tissue was correlated with E-cadherin and Snail expression,suggesting that FABP4 may promote CRC progression related to epithelial-mesenchymal transition(EMT).  相似文献   

13.
应用免疫组化方法,比较性地研究了大肠癌组织及其同一患者形态正常大肠粘膜组织中血管内皮细胞生长因子的表达,分析血管内皮细胞生长因子表达与大肠癌发生的年龄、性别、病理分期等因素的关系。结果显示,癌组织与正常大肠粘膜的血管内皮细胞生长因子表达存在明显差异,血管内皮细胞生长因子的表达与大肠癌患者年龄、性别、分化程度等因素不存在相关性,而与Ducks分期存在明显相关性。表明肿瘤血管的生成在大肠癌的生长发展方面起着至关重要的作用,血管内皮细胞生长因子的检测可以作为大肠癌诊断的重要参考指标。  相似文献   

14.
Insulin-like growth factor binding-protein-7 （IGFBP7） was obtained from our previous colonic adenocarcinoma （CRC） and normal mucosa suppression subtraction hybridization （SSH） cDNA libraries. By RT-PCR and immunohistochemistry, we found that IGFBP7 was overexpressed in CRC tissue compared to normal tissue. However, our in vitro experiments performed in 10 CRC cell lines showed that IGFBP7 expressed only in SW480 and Caco2 cell lines, which implied an underlying reversible regulatory mechanism. Using methylation-specific PCR （MSP） and bisulfite sodium PCR （BSP）, we found that its expression was associated with DNA hypomethylation of exonl. This was further supported by the in vitro study which showed restored IGFBP7 expression after demethylation agent 5-aza-2＇-deoxycytidine treatment. Correlation analysis between IGFBP7 expression and prognosis indicated that overexpression of IGFBP7 in CRC tissue correlated with favourable survival. Investigation of the functional role of IGFBP7 through transfection studies showed that IGFBP7 protein could inhibit growth rate, decrease colony formation activity, and induce apoptosis in RKO and SW620 cells, suggesting it a potential tumor suppressor protein in colorectal carcinogenesis. In conclusion, our study clearly demonstrated that IGFBP7 plays a potential tumor suppressor role against colorectal carcinogenesis and its expression is associated with DNA hypomethylation of exon 1.  相似文献   

15.
Ds-echinoside A (DSEA), a non-sulfated triterpene glycoside, was isolated from the sea cucumber Pearsonothuria graeffei. In vitro and in vivo investigations were conducted on the effects of DSEA on tumor cell adhesion, migration, invasion, and angiogenesis. In this study, we found that DSEA inhibited the proliferation of human hepatocellular liver carcinoma cells Hep G2, with a half-maximal inhibitory concentration (IC50) of 2.65 μmol/L, and suppressed Hep G2 cell adhesion, migration, and invasion in a dose-dependent manner. DSEA also reduced tube formation of human endothelial cells ECV-304 on matrigel in vitro and attenuated neovascularization in the chick embryo chorioallantoic membrane (CAM) assay in vivo. Immunocytochemical analysis revealed that DSEA significantly decreased the expression of matrix metalloproteinase-9 (MMP-9), which plays an important role in the degradation of basement membrane in tumor metastasis and angiogenesis. DSEA also increased the protein expression level of tissue inhibitor of metalloproteinase-1 (TIMP-1), an important regulator of MMP-9 activation. From the results of Western blotting, the expressions of nuclear factor-kappa B (NF-κB) and vascular endothelial growth factor (VEGF) were found to be remarkably reduced by DSEA. These findings suggest that DSEA exhibits a significant antimetastatic activity through the specific inhibition of NF-κB-dependent MMP-9 and VEGF expressions.  相似文献   

16.
Ciliary neurotrophic factor (CNTF) has pleiotropic actions on many neuronal populations as well as on glia. Signal transduction by CNTF requires that it bind first to CNTF-R, permitting the recruitment of gp130 and LIF-R, forming a tripartite receptor complex. Cells that only express gp130 and LIF-R, but not CNTF-R are refractory to stimulation by CNTF. On many target cells CNTF only acts in the presence of its specific agonistic soluble receptors. We engineered a soluble fusion protein by linking the COOH-terminus of sCNTF-R to the NH2-terminus of CNTF. Recombinant CNTF/sCNTF-R fusion protein (Hyper-CNTF) was successfully expressed in COS-7 cells. The apparent molecular mass of the Hyper-CNTF protein was estimated from western blots to be 75 kDa. Proliferation assays of transfected BAF/3 cells in response to CNTF and Hyper-CNTF were used to verify the activity of the cytokines. The proliferative results confirmed that CNTF required homodimerization of the gp130, CNTF-R and LIF-R receptor subunit whereas Hyper-CNTF required heterodimerization of the gp130 and LIF-R receptor subunit. We concluded that the fusion protein Hyper-CNTF had superagonistic activity on target cells expressing gp130 and LIF-R, but lacking membrane-bound CNTF-R. Project supported by the Scientific Research Foundation for the Returned Overseas Chinese Scholar, Zhejiang Province, China and SFB415, TP B5, Germany.  相似文献   

17.
INTRODUCTIONCiliaryneurotrophicfactor (CNTF)isanat urallyoccurringproteinwithamolecularmassofapproximately 2 2kDa .Itisexpressedinglialcellswithinthecentralandperipheralnervoussystems.CNTFstimulatesgeneexpression ,cellsurvivalordifferentiationinavarietyof…  相似文献   

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19.
Objective： To investigate whether vascular endothelial growth factor （VEGF） gene plasmid carried by polytetrafluoroethylene （PTFE） vascular graft materials could transfect endothelial cells （ECs） and promote their growth. Methods： PTFE vascular graft materials carried with pCDI-hVEGF121, pCDI or pEGFP were incubated in Tris-buffer solution and the values of optical density of 260 nm at different time were plotted, then the DNA controlled release curve was made. ECs derived from human umbilical vein were seeded on the pCDI-hVEGF121/pCDI/pEGFP-PTFE materials or tissue culture plates, ECs numbers were counted and VEGF protein concentrations at different time were measured by enzyme-linked immunoadsorbent assay method. Green fluorescent protein （GFP） expression in ECs on pEGFP-PTFE materials was examined with fluorescence mi- croscopy. Results： The controlled release curve showed that the gene released from PTFE materials was rapid within 8 h, then slowed down and that the gene released continuously even after 72 h. At 24, 72 and 120 h, ECs number and proliferation rate of pCDI-hVEGFI21-PTFE materials were higher than those ofpCDI or pEGFP-PTFE materials （P〈0.05）. VEGF protein concentration of pCDI-hVEGF121-PTFE materials was higher than that of pC DI or pEGFP-PTFE materials at 6, 24, 72 and 120 h （P〈0.01）. GFP expression in ECs on the pEGFP-PTFE materials could be detected by fluorescence microscopy. Conclusion： PTFE graft can be used as a carrier of VEGF gene plasmid, VEGF gene carried by PTFE can transfect ECs and promote ECs growth.  相似文献   

20.
绿色荧光蛋白及其在分子生物学上的应用   总被引：3，自引：0，他引：3  
许多海洋无脊椎动物体内都含有绿色荧光蛋白,这种蛋白质结构很特殊,在受到蓝光或紫外线刺激时可以发射绿色荧光,并不需要任何协同因子、底物,适合用作普遍的报告标记,尤其适合于活体细胞或组织。而且它发出的荧光稳定,检测简单,结果真实可靠。并且GFP对光漂白、氧化剂、还原荆以及其他许多化学试剂具有极强的稳定性．易于构建载体。它独特的性质引起了生物学界的广泛关注。本文简要地概述了绿色荧光蛋白及其在分子生物学上的应用,包括蛋白融合,细胞筛选,定位标记,基因表达调控,计算细胞生长速度等。  相似文献   

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