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排序方式: 共有1173条查询结果,搜索用时 31 毫秒
1.
Zheyuan Wang Zhiheng Shi Lu Zhang Huihan Zhang Yawu Zhang 《Pathology, research and practice》2019,215(3):499-505
Profilin 1 (PFN1) is a critical actin-regulatory protein; however, its functional role in hepatocellular carcinoma (HCC) progression remains to be further elucidated. In the present study, we observed that the expression levels of PFN1 were significantly decreased in HCC tissues and cell lines. Low PFN1 expression was significantly correlated with aggressive clinicopathological characteristics and poor prognosis of HCC patients. Further in vitro experiments demonstrated that overexpression of PFN1 remarkably inhibited the proliferation, migration, invasion and EMT of HCC cells. Moreover, we also found that PFN1 was a direct target gene of miR-19a-3p, and in HCC tissues, and there was a significantly inverse correlation between PFN1 mRNA and miR-19a-3p expression. Collectively, our results showed that PFN1 functions as a tumor suppressor in HCC, and might serve as a diagnostic and therapeutic target for HCC patients. 相似文献
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I. Simonitsch C. W. Kopp I. Mosberger T. Radaszkiewicz B. Volc-Platzer 《Virchows Archiv : an international journal of pathology》1996,427(5):477-481
The cutaneous lymphocyte associated antigen (CLA) recognized by the monoclonal antibody (moAb) HECA-452 plays a major role in the homing of lymphocyte subpopulations to the skin by binding to E-selectin on dermal microvessels. The factors responsible for the immigration of Langerhans cells (LC) and their precursors into the skin are still unknown, but because normal resting LC are also capable of expressing CLA, the antigen was proposed as a candidate LC-homing structure. To gain insight into these mechanisms, the expression of HECA-452 on neoplastic LC within and outside the skin was investigated in paraffin-embedded sections from 44 patients with localized and disseminated forms of Langerhans cell histiocytosis (LCH) presenting with proliferating cells positive for CD45, CD1a, S100 and HLADR. Irrespective of the clinical presentation or the type of organ involved, HECA-452-positive LC were detected in all biopsies tested (range 5->90%). The most prominent HECA-452 reactivity was observed in skin lesions and in areas with accumulations of eosinophilic granulocytes. Our data provide evidence for a heterogeneous expression of sLex/sLea structures in various stages of activated and/or differentiated LCH cells. Remarkably, CLA-antigen expression on LCH-cells was not restricted to cutaneous sites. In view of recent findings on the expression of HECA-452 on resting epidermal LC, our data are compatible with the view that local cytokine production by keratinocytes or cells from the surrounding infiltrate induce and/or modulate CLA expression on LC in both cutaneous and extra-cutaneous sites.This work is dedicated to Professor Dr. Thaddäus Radaszkiewicz, who died in September 1995 相似文献
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目的:对胰腺导管腺癌样本进行基因分析,筛选与胰腺导管腺癌相关的microRNA(miRNA),并初步分析目标miRNA与胰腺癌转化生长因子-β1(TGF-β1)信号通路的相关性。方法:收集在海南省中医院住院的胰腺导管癌患者术前外周静脉血血清标本19份,健康体检人群的外周静脉血血清标本21份作为非胰腺导管癌对照组。利用GCBI(Gene-Cloud Biotechnology Information)数据平台筛选与胰腺导管腺癌样本有关的基因并对其进行生物信息学分析,将筛选出的基因作为研究对象,用real-time PCR和蛋白质印迹法验证该基因在胰腺导管腺癌中的表达。通过改变胰腺导管腺癌细胞中该基因的表达水平观察其与TGF-β1之间的关系。结果:通过聚类分析和基因功能富集分析筛选出miRNA-21为胰腺导管癌相关基因。MiRNA-21在胰腺导管腺癌患者体内高表达。在miRNA-21过表达的PANC-1细胞中,TGF-β1表达受到抑制;但当miRNA-21的表达受到抑制时,TGF-β1的表达明显上升。结论:MiRNA-21在胰腺导管腺癌患者体内高表达,可调控TGF-β1的表达,从而参与胰腺导管腺癌的发生发展。 相似文献
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【目的】研究microRNA-30a-5p(miR-30a-5p)对人宫颈癌Hela细胞上皮-间质转化功能的影响及其相关机制。【方法】宫颈癌Hela细胞株分别转染目的mir的模拟物和阴性对照模拟物,分别以30a-5p组、NC组命名并标记细胞。同时,以未经过处理的Hela细胞作为对照(Control组)。分别用逆转录-聚合酶链反应法检测各组宫颈癌细胞的miR-30a-5p含量。Transwell实验检测3组细胞迁移能力和侵袭能力。Western-blot法检测3组细胞神经-钙粘素(N-cadherin)、α-连环蛋白(α-Catenin)和泛素水解酶22(USP22)表达水平。运用生物信息学方法预测miR-30a-5p的靶基因。采用Western blot法检测USP22过表达对miR-30a-5p抑制EMT的拮抗作用。双荧光素酶实验检测miR-30a-5p与USP22的关系。建立皮下移植瘤模型观察miR-30a-5p的体内作用。【结果】30a-5p组宫颈癌细胞miR-30a-5p的表达水平明显上调,表达水平为Control组的853.82(862.26~843.11)倍(P<0.01)。30a-5p组侵袭细胞数量8.17(8.32~8.03)明显低于Control组(P<0.01)。30a-5p组细胞N-cadherin蛋白的细胞内含量明显下降,α-Catenin蛋白的细胞内含量明显上升,USP22蛋白表达量明显降低。合并USP22过表达处理的30a-5p组宫颈癌细胞中N-cadherin蛋白表达量明显升高,α-Catenin蛋白表达量明显降低。双荧光素酶检验结果显示USP22为miR-30a-5p的下游靶基因(P<0.01)。30a-5p组皮下移植瘤明显小于Control组(P<0.01)。与Control组肿瘤组织相比,30a-5p组肿瘤组织miR-30a-5p的相对含量升高,USP22蛋白含量降低,N-cadherin蛋白的含量降低,α-Catenin蛋白含量升高。【结论】miR-30a-5p在宫颈癌Hela细胞中,可能通过靶向识别下游靶基因USP22,进而抑制其翻译。最终实现对宫颈癌细胞EMT过程的抑制。 相似文献
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目的:探讨表没食子儿茶素没食子酸酯(EGCG)对慢性阻塞性肺疾病(COPD)大鼠的保护作用和机制。方法:通过烟熏和脂多糖滴注建立大鼠COPD模型。每日灌胃给予100或200 mg/kg EGCG,4 w后观察肺部形态学改变。检测肺促炎细胞因子、MDA、GSH、SOD水平。免疫组化法评价纤维连接蛋白(fibronectin)和波形蛋白(vimentin)表达情况,Western blot检测TGF-β_1、p-Smad3表达水平,q PCR检测fibronectin、vimentin、TGF-β_1mRNA和微小RNA(miR)-133a/b-3p水平。结果:与正常对照组比较,模型组肺泡壁破损明显,肺组织促炎细胞因子、MDA及Smad3磷酸化水平显著升高,GSH、SOD、miR-133a/b-3p水平显著降低,fibronectin、vimentin、TGF-β_1蛋白表达显著升高。与模型组比较,EGCG能改善COPD大鼠的肺损伤,显著降低促炎细胞因子、MDA和Smad3的磷酸化水平,升高GSH、SOD、miR-133a/b-3p水平,并减少fibronectin、vimentin、TGF-β_1蛋白表达。结论:EGCG能改善COPD大鼠的肺损伤,其作用机制与调控肺TGF-β_1/Smad3和miR-133a/b-3p水平,抑制氧化应激和炎症有关。 相似文献
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Aim: Paeonol (2'-hydroxy-4'-methoxyacetophenone) from Cortex moutan root is a potential therapeutic agent for atherosclerosis. This study sought to investigate the mechanisms underlying anti-inflammatory effects of paeonol in rat vascular endothelial cells (VECs) in vitro.
Methods: VECs were isolated from rat thoracic aortas. The cells were pretreated with paeonol for 24 h, and then stimulated with ox-LDL for another 24 h. The expression of microRNA-21 (miR-21) and PTEN in VECs was analyzed using qRT-PCR. The expression of PTEN protein was detected by Western blotting. TNF-α release by VECs was measured by ELISA.
Results: Ox-LDL treatment inhibited VEC growth in dose- and time-dependent manners (the value of IC50 was about 20 mg/L at 24 h). Furthermore, ox-LDL (20 mg/L) significantly increased miR-21 expression and inhibited the expression of PTEN, one of downstream target genes of miR-21 in VECs. In addition, ox-LDL (20 mg/L) significantly increased the release of TNF-α from VECs. Pretreatment with paeonol increased the survival rate of ox-LDL-treated VECs in dose- and time-dependent manners. Moreover, paeonol (120 μmol/L) prevented ox-LDL-induced increases in miR-21 expression and TNF-α release, and ox-LDL-induced inhibition in PTEN expression. A dual-luciferase reporter assay showed that miR-21 bound directly to PTEN's 3'-UTR, thus inhibiting PTEN expression. In ox-LDL treated VECs, transfection with a miR-21 mimic significantly increased miR-21 expression and inhibited PTEN expression, and attenuated the protective effects of paeonol pretreatment, whereas transfection with an miR-21 inhibitor significantly decreased miR-21 expression and increased PTEN expression, thus enhanced the protective effects of paeonol pretreatment.
Conclusion: miR-21 is an important target of paeonol for its protective effects against ox-LDL-induced VEC injury, which may play critical roles in development of atherosclerosis. 相似文献
Methods: VECs were isolated from rat thoracic aortas. The cells were pretreated with paeonol for 24 h, and then stimulated with ox-LDL for another 24 h. The expression of microRNA-21 (miR-21) and PTEN in VECs was analyzed using qRT-PCR. The expression of PTEN protein was detected by Western blotting. TNF-α release by VECs was measured by ELISA.
Results: Ox-LDL treatment inhibited VEC growth in dose- and time-dependent manners (the value of IC50 was about 20 mg/L at 24 h). Furthermore, ox-LDL (20 mg/L) significantly increased miR-21 expression and inhibited the expression of PTEN, one of downstream target genes of miR-21 in VECs. In addition, ox-LDL (20 mg/L) significantly increased the release of TNF-α from VECs. Pretreatment with paeonol increased the survival rate of ox-LDL-treated VECs in dose- and time-dependent manners. Moreover, paeonol (120 μmol/L) prevented ox-LDL-induced increases in miR-21 expression and TNF-α release, and ox-LDL-induced inhibition in PTEN expression. A dual-luciferase reporter assay showed that miR-21 bound directly to PTEN's 3'-UTR, thus inhibiting PTEN expression. In ox-LDL treated VECs, transfection with a miR-21 mimic significantly increased miR-21 expression and inhibited PTEN expression, and attenuated the protective effects of paeonol pretreatment, whereas transfection with an miR-21 inhibitor significantly decreased miR-21 expression and increased PTEN expression, thus enhanced the protective effects of paeonol pretreatment.
Conclusion: miR-21 is an important target of paeonol for its protective effects against ox-LDL-induced VEC injury, which may play critical roles in development of atherosclerosis. 相似文献
9.
目的探讨微小RNA-155(miR-155)联合超声对分化型甲状腺癌淋巴结转移的诊断价值。方法选取接受治疗的分化型甲状腺癌患者112例作为甲状腺癌组,另选取同期收治的结节性甲状腺肿患者30例作为良性对照组。采用实时荧光定量PCR(qPCR)检测2组患者血清及组织中miR-155的相对表达量,分析分化型甲状腺癌患者血清及组织中miR-155的表达与临床病理参数的关系。采用受试者工作特征(ROC)曲线分析术前超声以及血清miR-155对分化型甲状腺癌淋巴结转移的诊断价值。结果甲状腺癌组的血清及组织中miR-155的相对表达量均明显高于良性对照组(P<0.01),有淋巴结转移、肿瘤直径>2 cm、TNM分期Ⅲ+Ⅳ期的患者血清及组织中miR-155的相对表达量分别高于无淋巴结转移、肿瘤直径≤2 cm、TNM分期Ⅰ+Ⅱ期的患者(均P<0.05)。ROC结果显示,超声以及血清miR-155对分化型甲状腺癌淋巴结转移均有一定的诊断价值,曲线下面积分别为:0.839(95%CI:0.760~0.919)、0.837(95%CI:0.763~0.912),但漏诊率和误诊率均超过10%。... 相似文献
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