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1.
Thomas J. Anderson Carol A. Lapp Michael A. Billman George S. Schuster 《Journal of clinical periodontology》1998,25(1):48-55
Abstract. Both transforming growth factor-β (TGF-ß) and platelet-derived growth factor (PDGF) have been shown to affect cell proliferation in vitro. The hypothesis being tested was that the effects of the 2 cytokines would be modulated by the presence of serum in the medium. Gingival fibroblasts, obtained from periodontally healthy patients, were maintained in primary culture. Dose response experiments were performed for each growth factor in serum-free medium and in medium containing natural or heat-inactivated fetal bovine serum (10% FBS). Changes in cell numbers were quantified by crystal violet staining. The optimal concentrations of the individual factors (10 ng/ml TGF-ßI, 20 ng/ml PDGF-BB) were then used when the 2 factors were tested in various sequences. In serum-free medium or in medium with 10% natural serum, the response to PDGF-BB was dose-dependent up to 40 ng/ml; however, with 10% heat-inactivated serum, the maximal response was seen at 20 ng/ml. The largest increase in cell numbers was produced by the simultaneous exposure to the two cytokines, rather than a sequential presentation. The findings suggest that the 48-h growth response of human gingival fibroblasts to 10 ng/ml TGF-ß1 or 20 ng/ml PDGF-BB in serum-free medium was equivalent to growth obtained in medium containing heat-inactivated 10% FBS without added growth factors. 相似文献
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Julius Klominek Berivan Baskin Dan Hauzenberger 《Clinical & experimental metastasis》1998,16(6):529-539
Platelet-derived growth factor BB (PDGF BB) and the PDGF receptor b are expressed on mesotheliomacells, but their biological function has not yet been defined. In the present study we used Boyden chambersfitted with filters coated with the adhesive matrix proteins fibronectin, laminin, collagen type IV or the non-matrixadhesive molecule poly-L-lysine (PLL). Mesothelioma cells migrated towards PDGF BB at concen-trationsranging from 0.78 to 12.5 ng/ml if matrix proteins were present as adhesive substrates. This migrationwas integrin dependent since the same cells failed to migrate if the adhesive interactions necessary for migra-tionwere provided by molecules other than integrins. Migration of mesothelioma cells on fibronectin, lamininor collagen-type IV in response to PDGF BB was inhibited if the cells were pretreated with blocking anti-bodiesto a3b1 integrin. These findings describe for the first time PDGF BB as a chemoattractant for malig-nantmesothelioma cells and that collaboration between PDGF receptor b and integrin a3b1 is necessaryfor the motile response of these cells to PDGF BB.©Kluwer Academic Publishers 相似文献
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Marc E. Lippman Robert B. Dickson Susan Bates Cornelius Knabbe Karen Huff Sandra Swain Mary McManaway Diane Bronzert Attan Kasid Edward P. Gelmann 《Breast cancer research and treatment》1986,7(2):59-70
Summary We consider the hypothesis that estrogen control of hormone dependent breast cancer is mediated by autocrine and paracrine growth factors secreted by the breast cancer cells themselves. Though we show direct, unmediated effects of estrogen on specific cell functions, we also provide evidence that human breast cancer cells secrete a collection of growth factors (IGF-I, TGF, TGF, a PDGF-like competency factor, and at least one new epithelial colony stimulating factor). Some of these are estrogen-regulated in hormone dependent cells, and are constitutively increased in cells which acquire independence either spontaneously or byras transfection. Collectively, the secreted growth factors are capable of promoting tumor formation by MCF-7 cells in nude mice, though not to the same extent as estrogens. There would seem to be potential for clinical intervention in the autocrine and paracrine control of breast cancer cells, including some cells which are no longer dependent on estrogens. 相似文献
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VEGF,PDGF和MVD在喉癌中的表达及临床意义 总被引:3,自引:2,他引:3
目的 探讨血管内皮生长因子(vascular endothelial growth factor,VEGF),血小板来源的内皮生长因子(platelet-derived endothelial growth factor,PDGF),Ⅷ因子测定的微血管密度(microvessel density,MVD)与喉癌微血管生成、临床分期和病理分级的关系。方法 应用免疫组织化学LASB法检测1998~1999年40例喉鳞状细胞癌和11例喉正常粘膜VEGF、PDGF、微血管密度的表达情况,结合临床相关因素进行统计分析。结果 喉鳞状细胞癌中VEGF表达在肿瘤T分级、临床分期、淋巴结转移和病理分级中有统计学意义(P<0.05)。PDGF计数标识指数与病人肿瘤T分级、临床分期中差异有统计学意义(P<0.05)。MVD测定均数在早、晚期分组中有统计学意义(P<0.05)。结论 喉癌的发展、侵袭需要持续的新生血管,本实验提示肿瘤增殖与理论相符,VEGF、PDGF和MVD可作为临床预测重要参考指标。 相似文献
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目的 建立酒精性肝病大鼠血浆中PDGF含量的HPLC测定方法.方法 色谱柱为Hypersil C18柱(250 mm×4.6 mm,5μm),流动相为乙腈-水,梯度洗脱(5%~65%,40 min),流速1.0 mL/min,柱温30℃,检测波长210nm,进样量10μL.结果 PDGF线性范围浓度在0.01~0.30... 相似文献
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川芎嗪对PDGF-BB诱导的大鼠血管平滑肌细胞增殖和骨桥蛋白mRNA表达的影响 总被引:11,自引:0,他引:11
目的:探讨川芎嗪对血小板源生长因子(PDGF BB)诱导的大鼠血管平滑肌细胞(VSMC)增殖及骨桥蛋白mRNA表达的影响。方法:大鼠胸主动脉平滑肌细胞体外培养,PDGF BB刺激VSMC ,采用MTT法和流式细胞仪测定川芎嗪对VSMC增殖的影响,逆转录聚合酶联反应(RT PCR)测定VSMC骨桥蛋白mRNA的表达水平。结果:川芎嗪可显著地抑制VSMC增殖(P <0 .0 1) ,使细胞生长停滞于G0 /G1期;PDGF BB诱导骨桥蛋白mRNA呈高表达,川芎嗪下调了这种表达。结论:川芎嗪能抑制体外的VSMC增殖,提示川芎嗪可能作为防治血管成形术后再狭窄的一种药物。 相似文献
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