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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   

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血管内皮生长因子家族及其受体   总被引:1,自引:0,他引:1  
血管内皮生长因子(VEGF)家族包括VEGF—A,-B,—C,—D,—E和胎盘生长因子(PIGF),都与同型的酪氨酸激酶受体VEGFR—1(Fltl),VEGFR—2(KDR/Flk1)和/或VEGFR—3(Flt4)结合。本文综述血管内皮生长因子家族及其受体在肿瘤血管生成、淋巴管生成及肿瘤转移中的作用。  相似文献   

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Background

Epithelial-mesenchymal transition (EMT) is believed to be the critical process in malignant tumor invasion and metastases, and has a great influence on improving the survival rate in non-small-cell lung cancer (NSCLC) patients. Recent studies suggested that eukaryotic initiation factor 5A-2 (eIF5A-2) might serve as an adverse prognostic marker of survival. We detected eIF5A-2 in NSCLC A549 cells, and found that the invasive capability correlates with the eIF5A-2 expression.

Methods

Transforming growth factor (TGF)-β1 was used to induce EMT in A549 cells. Western blotting, immunofluorescence, wound healing assay, and transwell-matrigel invasion chambers were used to identify phenotype changes. Western blotting was also used to observe changes of the expression of eIF5A-2. We down-regulated the eIF5A-2 expression using an eIF5A-2 siRNA and identified the phenotype changes by western blotting and immunofluorescence. We tested the change of migration and invasion capabilities of A549 cells by the wound healing assay and transwell-matrigel invasion chambers.

Results

After stimulating with TGF-β1, almost all A549 cells changed to the mesenchymal phenotype and acquired more migration and invasion capabilities. These cells also had higher eIF5A-2 protein expression. Down-regulation of eIF5A-2 expression with eIF5A-2 siRNA transfection could change the cells from mesenchymal to epithelial phenotype and decrease tumor cell migration and invasive capabilities significantly.

Conclusions

The expression of eIF5A-2 was up-regulated following EMT phenotype changes in A549 cells, which correlated with enhanced tumor invasion and metastatic capabilities. Furthermore, in the A549 cell line, the process of EMT phenotype change could be reversed by eIF5A-2 siRNA, with a consequent weakening of both invasive and metastatic capabilities.  相似文献   

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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   

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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   

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Objective:To explore the feasibility of using regenerated silk fibroin membrane to construct artificial skin substitutes for wound healing, it is necessary to evaluate its cytocompatibility. Methods:The effects of regenerated silk fibroin film on cytotoxicity, adhesion, cell cycle, and apoptosis of L929 cells, growth and vascular endothelial growth factor (VEGF) expression of ECV304 cells, and VEGF, angiopoietin-1 (Ang-1), platelet-derived growth factor (PDGF) and fibroblast growth factor 2 (FGF2) expressio...  相似文献   

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目的观察鞣花酸对前列腺癌PC-3细胞株的影响。方法:体外培养人前列腺癌PC-3细胞,加入0μg/ml、2.5μg/ml、5μg/ml、10μg/ml、20μg/ml的鞣花酸作用于PC-3细胞,分别作用12小时、24小时和48小时后,应用MTr法测定各浓度组鞣花酸对PC-3细胞的生长抑制作用。应用流式细胞仪检测鞣花酸作用48小时后,PC-3细胞的周期时相变化及凋亡情况。应用免疫细胞化学检测10μg/ml鞣花酸作用24小时后,实验组与对照组细胞Caspase-3蛋白表达情况。结果:鞣花酸明显抑制PC-3细胞的生长,抑制效应呈时间依赖型和浓度依赖型,与对照组比较均有统计学意义(P〈0.05)。应用流式细胞仪检测结果显示,鞣花酸可将PC-3细胞阻滞于G1/S期,并诱导PC-3细胞凋亡。免疫细胞化学结果显示实验组Ctmpase-3蛋白表达明显升高。结论:鞣花酸对前列腺癌PC-3细胞株有明显的生长抑制和诱导凋亡作用。  相似文献   

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拟康氏木霉胞外粗多糖经纯化得两个单一组分TPeps-1和TPeps-2.用0.25mg/mLTPeps-2处理黄瓜幼苗,处理叶在第一天就产生活性氧爆发,of含量是对照的117.5%;第二天处理中SOD活性达到峰值,为对照的135.5%;用黄瓜灰霉病菌接种黄瓜幼苗也产生了较强的诱导效应,处理叶第一天O2^-含量是对照的139.7%,第二天SOD活性为对照的141.9%;而且两组试验中未处理的系统叶中也存在较弱的诱导反应.结果说明TPeps-2能模拟病原入侵激发黄瓜叶片活性氧代谢途径.  相似文献   

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Royal jelly (RJ) from honeybee has been widely used as a health promotion supplement. The major royal jelly proteins (MRJPs) have been identified as the functional component of RJ. However, the question of whether MRJPs have anti-senescence activity for human cells remains. Human embryonic lung fibroblast (HFL-I) cells were cultured in media containing no MRJPs (A), MRJPs at 0.1 mg/ml (B), 0.2 mg/ml (C), or 0.3 mg/ml (D), or bovine serum albumin (BSA) at 0.2 mg/ml (E). The mean population doubling levels of cells in media B, C, D, and E were increased by 12.4%, 31.2%, 24.0%, and 10.4%, respectively, compared with that in medium A. The cells in medium C also exhibited the highest relative proliferation activity, the lowest senescence, and the longest telomeres. Moreover, MRJPs up-regulated the expression of superoxide dismutase-1 (SOD1) and down-regulated the expression of mammalian target of rapamycin (MTOR), catenin beta like-1 (CTNNB1), and tumor protein p53 (TP53). Raman spectra analysis showed that there were two unique bands related to DNA synthesis materials, amide carbonyl group vibrations and aromatic hydrogens. These results suggest that MRJPs possess anti-senescence activity for the HFL-I cell line, and provide new knowledge illustrating the molecular mechanism of MRJPs as anti-senescence factors.  相似文献   

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The development of ovarian follicular cells is controlled by multiple circulating and local hormones and factors, including follicle-stimulating hormone (FSH) and epidermal growth factor (EGF). In this study, the stage-specific effect of EGF on FSH-induced proliferation of granulosa cells was evaluated in the ovarian follicles of egg-laying chickens. Results showed that EGF and its receptor (EGFR) mRNAs displayed a high expression in granulosa cells from the prehierarchical follicles, including the large white follicle (LWF) and small yellow follicle (SYF), and thereafter the expression decreased markedly to the stage of the largest preovulatory follicle. SYF represents a turning point of EGF/EGFR mRNA expression during follicle selection. Subsequently the granulosa cells from SYF were cultured to reveal the mediation of EGF in FSH action. Cell proliferation was remarkably increased by treatment with either EGF or FSH (0.1–100 ng/ml). This result was confirmed by elevated proliferating cell nuclear antigen (PCNA) expression and decreased cell apoptosis. Furthermore, EGF-induced cell proliferation was accompanied by increased mRNA expressions of EGFR, FSH receptor, and the cell cycle-regulating genes (cyclins D1 and E1, cyclin-dependent kinases 2 and 6) as well as decreased expression of luteinizing hormone receptor mRNA. However, the EGF or FSH-elicited effect was reversed by simultaneous treatment with an EGFR inhibitor AG1478. In conclusion, EGF and EGFR expressions manifested stage-specific changes during follicular development and EGF mediated FSH-induced cell proliferation and retarded cell differentiation in the prehierarchical follicles. These expressions thus stimulated follicular growth before selection in the egg-laying chicken.  相似文献   

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Multidrug resistance (MDR) is the major impediment to cancer chemotherapy. The expression of lung resistance-related protein (LRP), a non-ATP-binding cassette (ABC) transporter, is high in tumor cells, resulting in their resistance to a variety of cytotoxic drugs. However, the function of LRP in tumor drug resistance is not yet explicit. Our previous studies had shown that Kinesin KIF4A was overexpressed in cisplatin (DDP)-resistant human lung adenocarcinoma cells (A549/DDP cells) compared with A549 cells. The expression of KIF4A in A549 or A549/DDP cells significantly affects cisplatin resistance but the detailed mechanisms remain unclear. Here, we performed co-immunoprecipitation experiments to show that the tail domain of KIF4A interacted with the N-terminal of LRP. Immunofluorescence images showed that both the ability of binding to LRP and the motility of KIF4A were essential for the dispersed cytoplasm distribution of LRP. Altogether, our results shed light on a potential mechanism in that motor protein KIF4A promotes drug resistance of lung adenocarcinoma cells through transporting LRP-based vaults along microtubules towards the cell membrane. Thus KIF4A might be a cisplatin resistance-associated protein and serves as a potential target for chemotherapeutic drug resistance in lung cancer.  相似文献   

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INTRODUCTION Gemcitabine (2′,2′-difluorodeoxycytidine) is asynthetic pyrimidine nucleoside analogue with cyto-toxic activity in non-small-cell lung cancer (NSCLC)(Anderson et al., 1994; Abratt et al., 1994; Lund et al.,1994). Gemcitabine is a prodrug which, through de-oxycytidine kinase and other nucleotide kinases, ex-erts its cytotoxic effects through its active intracellu-lar metabolites, gemcitabine diphosphate andtriphosphate (Guchelaar et al., 1996;…  相似文献   

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目的:探讨复方丹参片早期干预对APP/PS1转基因小鼠学习记忆的影响及作用机制。方法:4月龄野生型小鼠和APP/PS1转基因小鼠分别灌胃给予溶剂或药物8周后,采用新物体识别实验和跳台实验评价复方丹参片对小鼠行为学表现的影响;应用ELISA检测小鼠海马β淀粉样蛋白(β-amyloid protein,Aβ)Aβ40、Aβ42的含量;采用Real time PCR和Western blot分别检测胰岛素分解酶(insulin degrading enzyme,IDE)/脑啡肽酶(neprilysin,NEP)m RNA和蛋白水平的变化。结果:新物体识别实验结果显示,复方丹参片720 mg·kg-1显著性增加APP/PS1转基因小鼠对新物体的识别指数。跳台实验结果显示,复方丹参片720、360 mg·kg-1显著性减少APP/PS1转基因小鼠学习次数,此外,复方丹参片720 mg·kg-1明显增加小鼠在平台的停留时间。ELISA结果显示,复方丹参片720、360 mg·kg-1显著性降低APP/PS1转基因小鼠海马Aβ40、Aβ42水平。Real-time PCR结果显示,复方丹参片720 mg·kg-1显著性上调APP/PS1转基因小鼠海马IDE和NEP m RNA的表达。Western blot结果显示,复方丹参片720 mg·kg-1显著性增加小鼠海马IDE蛋白表达。结论:复方丹参片可改善APP/PS1转基因小鼠学习记忆能力,可能与减少海马Aβ水平和增加IDE的表达有关。  相似文献   

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本文主要研究了Al(Ⅲ)-CAS-OP三元配合物显色体系。在pH=5.5的HAc-NaAc介质中,该配合物的λmax=560 nm,εmax=4.8×104 L·mol-1·cm-1。Al(Ⅲ)量在0~3.2 mg/L范围内线性关系良好,符合比尔定律,其线性回归方程为A=478 33C-0.010 3;相关系数r=0.999 0。摩尔比法测定了该配合物配位比为1:2:4。以抗坏血酸作掩蔽剂,利用该体系测定粉条中的铝含量,回收率为91%~101%。  相似文献   

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Objective: To conduct a randomized comparative trial of pharmacokinetics, efficacy and toxicity profile treatment with 1200 mg/m^2 gemcitabine using standard 30-min infusion or fixed dose rate (FDR) infusion [10 mg/(m^2-min)] on days 1 and 8 plus carboplatin AUC (area under curve) 5 on day 1 in Chinese non-small-cell cancer patients. Twelve patients were enrolled in this study. Methods: Plasma gemcitabine concentrations were measured by ion-pair reversed phase high performance liquid chromatography. Antitumoral activity and toxicity of gemcitabine was assessed according to World Health Organization criteria. Results: The obtained mean parameters, such as T1/2 (elimination half time), AUC, and CL (clearance), were consistent with those reported in literature. Qualified response rate in our study was 33.3% for standard arm and 50% for FDR ann. Additional 50% and 33.3% patients contracted stable disease (SD) in standard arm and FDR arm, respectively. The predominant toxicity was hematologic, and patients in the standard infusion ann experienced consistently more hematologic toxicity, Conclusion: Pharmacokinetic and clinical data in this trial support the continued evaluation of the FDR infusion strategy with gemcitabine.  相似文献   

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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   

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The lysyl oxidase (LOX) family encodes the copper-dependent amine oxidases that play a key role in determining the tensile strength and structural integrity of connective tissues by catalyzing the crosslinking of elastin or collagen. Estrogen may upregulate the expression of LOX and lysyl oxidase-like 1 (LOXL1) in the vagina. The objective of this study was to determine the effect of estrogen on the expression of all LOX family genes in the urogenital tissues of accelerated ovarian aging mice and human Ishikawa cells. Mice and Ishikawa cells treated with estradiol (E2) showed increased expression of LOX family genes and transforming growth factor β1 (TGF-β1). Ishikawa cells treated with TGF-β1 also showed increased expression of LOX family genes. The Ishikawa cells were then treated with either E2 plus the TGF-β receptor (TGFBR) inhibitor SB431542 or E2 alone. The expression of LOX family genes induced by E2 was reduced in the Ishikawa cells treated with TGFBR inhibitor. Our results showed that E2 increased the expression of the LOX family genes, and suggest that this induction may be mediated by the TGF-β signal pathway. E2 may play a role in regulating the expression of LOX family genes.  相似文献   

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