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81.
目的探讨miR-483-5p在肾上腺皮质癌中的作用及其可能的作用机制。方法荧光定量PCR法检测miR-483-5p和CDK15在肾上腺皮质癌组织和细胞系中的表达,CCK-8增殖试验测定miR-483-5p对细胞增殖的影响,Transwell法检测ACC细胞侵袭性的变化。荧光素酶试验和挽救实验验证miR-483-5p与CDK15相关的分子机制。结果miR-483-5p在肾上腺皮质癌组织中高表达(2.36±1.02 vs 1.09±0.43),CDK15在肾上腺皮质癌组织中低表达(0.57±0.26 vs 1.06±0.32)。荧光素酶检测证实CDK15是miR-483-5p的直接靶点。过表达miR-483-5p可通过下调CDK15的表达促进ACC细胞的增殖(24 h:0.26±0.03 vs 0.23±0.04,48 h:0.56±0.05 vs 0.41±0.03,72 h:0.73±0.04 vs 0.59±0.03)和侵袭能力(95.78±4.66 vs 23.89±2.52)。结论miR-483-5p可通过下调CDK15的表达促进肾上腺皮质癌的发生发展,其可作为肾上腺皮质癌的潜在生物标志物及治疗肾上腺皮质癌的新的作用靶点。 相似文献
82.
Weidong Zhang Fengliang Wang Pengfei Xu Chen Miao Xin Zeng Xianwei Cui Cheng Lu Hui Xie Hong Yin Fei Chen Jingjing Ma Sheng Gao Ziyi Fu 《Toxicology letters》2014
Perfluorooctanoic acid (PFOA) is widely used because of its stain-resistant and water-repellant properties. This study aimed to explore the molecular mechanisms undergoing the stimulation effects of PFOA on cancer cell invasion and matrix metalloproteinases (MMPs) expression. Trans-well filter assay showed that PFOA exposure (≥5 nM) evidently enhanced the invasion ability of the breast cancer cells MDA-MB-231. Luciferase reporter assay, quantitative real-time PCR, western blotting and gelatin zymography consistently demonstrated that mRNA and protein levels of MMP-2/-9 were increased in the cells after PFOA treatment (P < 0.05 each). Western blotting revealed that PFOA could activate nuclear factor kappaB (NF-κB) by accelerating NF-κB translocation into the nucleus. Furthermore, addition of NF-κB inhibitor in culture medium could suppress the breast cancer cells invasiveness enhancement and MMP-2/-9 overexpression. This study indicates that PFOA can stimulate breast cancer cells invasion and up-regulate matrix metalloproteinase-2/-9 expression mediated by activating NF-κB, which deserves more environmental health concerns. 相似文献
83.
《Toxicology in vitro》2014,28(3):335-339
Metastasis contributes to the escalating mortality rate among cancer patients worldwide. The search for novel and more effective anti-metastatic agent is crucial owing to the lack of anticancer drugs that can successfully combat metastasis. Hence, this study aims to examine the effects of 2-Methoxy-1,4-Naphthoquinone (MNQ) towards the metastasis of MDA-MB-231 cells. In invasion assays, the number of cells permeating across a Matrigel barrier was found to be decreased in a dose-dependent manner upon treatment with MNQ (0–7.5 μM). In wound-healing migration assays, MNQ exhibited dose-dependent inhibition of cell migration in which significant reduction in the zone of closure was observed as compared to untreated controls. Furthermore, the proteolytic activity of a pivotal metastatic mediator, matrix metalloproteinase-9 (MMP-9) was also downregulated by MNQ as determined by gelatin zymography. This study reports for the first time, the ability of MNQ to inhibit the invasion and migration characteristics of a highly metastatic MDA-MB-231 cancer cell line. 相似文献
84.
鼠疫菌9.5kb质粒对假结核菌粘附、侵袭上皮细胞能力的影响 总被引:2,自引:0,他引:2
用电穿孔方法把克隆的鼠疫菌9.5kb质粒转移到不同血清型的假结核菌中,研究了不同实验条件下9.5kb质粒对假结核粘附、侵袭上皮细胞(Hep-2)能力的影响。结果显示,尽管9.5kb质粒不能明显改变假结核菌的粘附、侵袭特征,但相对于亲本株而言,转化后的菌体在所有实验条件下侵袭上皮细胞的能力确定有所下降,表明9.5kb质粒介导的粘附、侵袭机制有别于假结核菌。由此,分析和评价了9.5kb质粒在粘附、侵袭 相似文献
85.
Jian Li Geng Guo Jin Li Jiehe Hao Jianjun Zhang Yongping Guo Hui Yu 《The Journal of surgical research》2014
Background
The proto-oncogene dishevelled (Dvl) is a critical component of the Wnt/β-catenin signaling pathway, and its elevated expression in various tumor types is associated with malignancy. However, a role for Dvl in glioma has not been explored.Materials and methods
To determine whether Dvl expression is elevated in human glioma, we examined the protein levels in 67 human glioma samples and 3 normal brain specimens by Western blotting and immunohistochemistry. To investigate a possible association of Dvl with the malignant phenotype in glioma, the correlation of the Dvl immunoreactivity score (IRS) with β-catenin IRS, the tumor proliferation index (PI), and tumor invasion index (II) were determined for each sample.Results
The Dvl IRS, β-catenin IRS, PI, and II increased significantly with the pathologic grade of glioma (P <0.001) with average scores of 3.46 ± 3.45, 3.92 ± 3.28, 30.93 ± 17.92, and 20.43 ± 11.79, respectively. Furthermore, the PI and II were significantly higher for the Dvl-positive group than the Dvl-negative group (P <0.001). Correlation analysis demonstrated that β-catenin IRS, PI, and II were positively correlated with Dvl IRS.Conclusions
Dvl overexpression may contribute to the malignant proliferation and invasion of human glioma. 相似文献86.
目的探讨胶质瘤患者肿瘤组织和血浆中基质金属蛋白酶-9(MMP-9)的表达、两者之间的关系及意义。方法收集40例胶质瘤患者病理标本、患者术前血浆及临床资料,分成高度恶性组和低度恶性组。10例因重度颅脑损伤而行内减压手术切除的脑组织和患者术前血浆,作为对照组。运用免疫组织化学染色法对胶质瘤组织标本中MMP-9表达进行半定量分析。运用酶联免疫吸附测定法检测血浆中总MMP-9浓度。结果 MMP-9在正常脑组织中无表达,高度恶性组瘤组织中MMP-9的表达显著高于低度恶性组(P=0.027)和对照组(P=0.000)。各级别胶质瘤组MMP-9血浆浓度均显著高于对照组(P0.001)。瘤组织MMP-9强阳性表达组血浆MMP-9浓度显著高于阴性组(P=0.022)和弱阳性组(P=0.048),血浆MMP-9浓度与相应肿瘤组织MMP-9的表达水平呈正相关(rs=0.530,P=0.000)。结论瘤组织MMP-9表达与胶质瘤恶性程度呈正相关,其高表达可能与胶质瘤的侵袭转移有关;胶质瘤患者血浆MMP-9浓度一定程度上反映出瘤组织中MMP-9表达水平。 相似文献
87.
目的 探讨骨桥蛋白(OPN)对甲状腺癌生物学行为的影响。方法 SW579细胞置于6孔板中培养,采用随机数字表法分成对照组、阴性对照组、OPN siRNA干扰组3组,每组3个孔,每个孔2 mL,细胞密度为1×104/mL。对照组不作任何处理,阴性对照组转染OPN阴性序列,OPN siRNA干扰组转染OPN siRNA序列。采用实时荧光定量逆转录聚合酶链反应(qRT-PCR)测定并比较转染后3组细胞OPN、MMP-2、MMP-9、Caspase-3的mRNA水平,四甲基偶氮唑盐(MTT)测定转染后3组细胞的抑制率,流式细胞仪检测转染后3组细胞凋亡率,Transwell小室检测转染后3组细胞的侵袭力,蛋白免疫印迹法(Western blot)检测3组OPN、MMP-2、MMP-9、Casepase-3的蛋白水平。结果 OPN siRNA干扰组的OPN mRNA的表达水平显著低于对照组和阴性对照组,细胞凋亡率显著高于对照组以及阴性对照组,侵袭能力显著低于对照组和阴性对照组,OPN、MMP-2、MMP-9 mRNA和蛋白水平显著低于对照组和阴性对照组,Casepase-3mRNA和蛋白水平显著高于对照组和阴性对照组,差异均有统计学意义(P<0.05)。结论 OPN干扰后SW579细胞增殖和侵袭能力下降,凋亡率增加,其机制可能与凋亡蛋白caspase-3水平增加,MMP-2、MMP-9水平下降有关。 相似文献
88.
Hyun Ji Kim Mi Kyung Park Soo Youl Kim Chang Hoon Lee 《Biomolecules & therapeutics.》2014,22(6):540-546
The high mortality rates associated with cancer reflect the metastatic spread of tumor cells from the site of their origin. Metastasis, in fact, is the cause of 90% of cancer deaths. Therefore, considerable effort is being made to inhibit metastasis. In the present study, we screened ketotifen for anti-migratory and anti-invasive activities against MDA-MB-231 breast cancer and HT-1080 fibrosarcoma cancer cells. Cancer cell migration and invasion were measured using multi-well chambers. Additionally, western blots were used to examine the effects of ketotifen on the expressions of CDC42, Rho, Rac, and matrix metalloproteinase 9 (MMP-9). The results showed that ketotifen dose-dependently suppressed the migration and invasion of MDA-MB-231 and HT-1080 cells. Ketotifen also suppressed the expressions of CDC42, Rac, and Rho, which, significantly, are involved in MDA-MB-231 and HT-1080 cancer cell migration. Moreover, ketotifen suppressed the expression and activity of MMP-9, which is involved in degradation of the extracellular matrix leading to invasion. The overall data suggested that ketotifen suppresses the migration and invasion of MDA-MB-231 and HT-1080 cancer cells via inhibition of CDC42, Rac, Rho, and MMP-9 expression. 相似文献
89.
《Pathology, research and practice》2020,216(11):153157
ObjectiveThis study aimed at probing into the effect of lncRNA NCK1-AS1 on proliferation, migration and invasion of non-small cell lung cancer (NSCLC) cells and its regulatory function on miR-512-5p/p21 molecular axis.MethodsQuantitative real-time polymerase chain reaction (qRT-PCR) was used to assess the expressions of NCK1-AS1 and miR-512-5p in NSCLC tissues and cell lines. The alterations of cell proliferation, migration, invasion and cell cycle were examined by cell counting kit-8 (CCK-8) assay, BrdU experiment, Transwell experiment and flow cytometry, respectively. The dual-luciferase reporter assay and RNA immunoprecipitation experiment were performed to validate the binding relationships between miR-512-5p and NCK1-AS1, and miR-512-5p the 3'UTR of p21 mRNA. Western blot was used to determine the effects of NCK1-AS1 and miR-512-5p on p21 protein expression.ResultsNCK1-AS1 expression was up-regulated in NSCLC tissues and cells, and its high expression was correlated with shorter overall survival time and faster progression of patients. Overexpression of NCK1-AS1 promoted NSCLC cell proliferation, migration and invasion, and accelerated the cell cycle, whereas NCK1-AS1 siRNA inhibited these malignant biological behaviors, and arrested cell cycle. NCK1-AS1 could bind to miR-512-5p, p21 was verified as a target gene of miR-512-5p, and NCK1-AS1 could up-regulate the expression of p21 in NSCLC cells via repressing miR-512-5p expression.ConclusionNCK1-AS1 promotes NSCLC progression by regulating miR-512-5p/p21 molecular axis. 相似文献
90.
目的 探讨微小RNA-21(miRNA-21)表达介导食管鳞癌细胞的生物学特性。方法 转染miRNA-21正义表达载体、miRNA-21空载体及miRNA-21抑制剂,通过Real-time PCR实验,以食管鳞状上皮癌TE-1正常细胞为对照组,检测转染结果。采用细胞计数试剂盒-8(CCK-8)对细胞增殖活性进行检测;采用流式细胞术检测细胞凋亡能力;通过Transwell小室和划痕实验观察TE-1细胞侵袭能力及迁移能力;通过集落形成实验观察TE-1细胞对放疗敏感性变化;采用SPSS 19.0统计学软件对所得数据进行分析。结果 Real-time PCR结果显示,转染miRNA-21抑制剂后,TE-1细胞中miRNA-21的表达水平明显降低(P<0.05)。相比正常细胞生长组,阳性对照组、阴性对照组转染miRNA-21抑制剂后,TE-1细胞增殖能力降低,细胞凋亡加快(P<0.05)。此外,实验抑制组中细胞侵袭和迁移能力下降。集落形成实验分析显示,抑制miRNA-21表达明显提高了TE-1细胞对放射的敏感性。结论 下调miRNA-21可降低食管鳞状上皮癌TE-1细胞的增殖、侵袭、迁移能力及放疗的敏感性,是未来治疗食管癌的潜在靶点。 相似文献