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Psoriasin (S100A7) is expressed in several epithelial malignancies including breast cancer. Although S100A7 is associated with the worst prognosis in estrogen receptor α-negative (ERα(-)) invasive breast cancers, its role in ERα-positive (ERα(+)) breast cancers is relatively unknown. We investigated the significance of S100A7 in ERα(+) breast cancer cells and observed that S100A7 overexpression in ERα(+) breast cancer cells, MCF7 and T47D, exhibited decreased migration, proliferation, and wound healing. These results were confirmed in vivo in nude mouse model system. Mice injected with S100A7-overexpressing MCF7 cells showed significant reduction in tumor size compared with mice injected with vector control cells. Further mechanistic studies revealed that S100A7 mediates the tumor-suppressive effects via a coordinated regulation of the β-catenin/TCF4 pathway and an enhanced interaction of β-catenin and E-cadherin in S100A7-overexpressing ERα(+) breast cancer cells. We observed down-regulation of β-catenin, p-GSK3β, TCF4, cyclin D1, and c-myc in S100A7-overexpressing ERα(+) breast cancer cells. In addition, we observed increased expression of GSK3β. Treatment with GSK3β inhibitor CHIR 99021 increased the expression of β-catenin and its downstream target c-myc in S100A7-overexpressing cells. Tumors derived from mice injected with S100A7-overexpressing MCF7 cells also showed reduced activation of the β-catenin/TCF4 pathway. Therefore, our studies reveal for the first time that S100A7-overexpressing ERα(+) breast cancer cells exhibit tumor suppressor capabilities through down-modulation of the β-catenin/TCF4 pathway both in vitro and in vivo. Because S100A7 has been shown to enhance tumorigenicity in ERα(-) cells, our studies suggest that S100A7 may possess differential activities in ERα(+) compared with ERα(-) cells. 相似文献
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大口鲇和鲇鱼血清蛋白质及同工酶的比较研究 总被引:10,自引:0,他引:10
采用聚丙烯酰胺梯度凝胶垂直板电泳,分析了大口鲇和鲇鱼的血清蛋白质以及心脏、肝脏、眼和肌肉4种组织的EST及MDH同工酶。结果表明,大口鲇和鲇鱼的血清蛋白质均能分离出20条左右的谱带,两者既表现出相同的谱带,又表现出迁移率和含量都不同的带型。两者的EST和MDH同工酶在4种组织及血清中均能特异性地表达,存在明显的组织和物种特异性。本文认为肝脏是研究大口鲇和鲇鱼种群生化遗传结构与变异的理想材料,同时还探讨了两种鲇鱼的M DH同工酶位点。
Abstract:The serum proteins and isozymes in four tissues (heart,liver,eye and musele)of Smeridionalis Chen and S.asotus Linnaeus were analyzed by polyacrylamide gradient gel vertical electrophoresis.The isozymes are esterase(EST)and malate dehytrogenase(MDH).The results showed that electrophoretograme of serum proteins were about 20 protein pattens in two species catfish,they were either the same protein pattens or the different pattens.Electrophoretogram of isozymes(EST,MDH)in two species catfish indicated tissues and species specificity.Experiment considered that the liver was a good material studied biochemical genetic constitution and variation in species group of S.meridionalis Chen and S.asotus Linnaeus. 相似文献
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中国科学院内蒙古草原生态系统定位站学术交流会已于1981年1月29日至2月3日在北京召开。参加这次会议的有中国科学院植物研究所、动物研究所、综合考察委员会及内蒙古大学等17个单位,42人。 相似文献
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FangJun Yuan Wenbo Zhou Can Zou Zhiyun Zhang Hongsheng Hu Zongqing Dai YouShun Zhang 《Molecular and cellular biochemistry》2010,343(1-2):155-162
Hepatocellular carcinoma (HCC) is considered as a disease of dysfunction of the stem cells. Studies on stem cells have demonstrated that Oct4 plays a pivotal role in embryo regulation. In order to understand the role of Oct4 in HCC and the relationship among Oct4 and wnt/β-catenin and TGF-β signal pathways, we have detected the expression of Oct4, Nanog, Sox2, STAT3 as well as the genes in wnt/β-catenin, and TGF-β families in HCC cell lines and in tumor specimens from HCC patients. The authors found that Oct4 was expressed in all of the four HCC cell lines and the tumor specimens from HCC patients. Some other genes were also expressed in them with different level including Nanog, Sox2, STAT3 and TCF3, wnt10b, β-catenin, ELF, Smad3 and Smad4. The ability of the clone formation and migration of the HepG2 decreased after Oct4 was knockdowned. Silencing of Oct4 and TCF3 in HCC cell line HepG2 revealed that there were complicated relationships among Oct4, wnt/β-catenin family and TGF-β family genes. Knockdowning Oct4 reduced the expression of TGF-β family genes ELF, Smad3, Smad4 and wnt/β-catenin family genes, wnt10b, and β-catenin but increased TCF3. In reverse, knockdowning TCF3 led to the increased expression of Oct4 and TGF-β family genes. In conclusion, the expression of Oct4 in HCC may play an important role as in stem cell. Because Oct4 improves not only the function of wnt/β-catenin, but also the TGF-β signal pathways, the significance of its expression in HCC might be more complicated than we evinced before. 相似文献
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原生质体的大量制备是研究原生质体转化、诱变、融合等技术的关键,液泡的制备对研究液泡中分解、转运有机物的特性具有重要意义,但目前分离技术还不够成熟.本研究从聚多曲霉菌菌丝中分离原生质体和液泡并对分离条件进行优化,以聚多曲霉菌DJ515-2菌丝为材料,探索不同因素对原生质体和液泡制备分离效果的影响.结果表明,聚多曲霉菌DJ515-2在菌龄42 h,以3%纤维素酶、1%蜗牛酶和3%的溶壁酶组成复合酶液,25℃下酶解4 h,原生质体达到最大产量,为5.167×105个/mL.同时,在此基础上裂解液泡的最优条件为pH7.5、1.0mol/L KCl、0.020%Triton X-10,其产量达2.63×105个/mL,产率为原生质体的50.8%,相比采用多元碱化合物诱导真菌原生质体裂解释放液泡的产率增加了 40%~45%.本研究为真菌和植物的各种原生质体技术及基于亚细胞层面的研究提供了材料基础. 相似文献
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Yang B Chen GY Song XP Yang LQ Han CR Wu XY Li XM Zou BY 《Bioorganic & medicinal chemistry letters》2012,22(11):3828-3830
Two new daphnane diterpenoids (1 and 2), together with four known analogues (3-6) were isolated from Trigonostemon xyphophylloides. Their structures were elucidated by spectroscopic analysis. Compounds 1 and 2 were evaluated for in vitro cytotoxic activities against the SPCA-1 (human lung cancer) and BEL-7402 (human hepatocellular carcinoma) cancer cell lines. Trigoxyphin I (2) showed modest cytotoxicity against two tumor cell lines. 相似文献
70.
GPR39, an orphan receptor belonging to the family of G protein-coupled receptors, was originally reported to be the receptor of obestatin. However recently, numerous reports have questioned this conclusion. In mammals, GPR39 was reported to be involved in the regulation of gastrointestinal and the metabolic functions. In this article, a latest and brief review on the receptor family, structure, distribution and physiological functions of GPR39 has been reported. 相似文献