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目的应用RNA干扰(RNA interference,RNAi)技术敲低恶性胶质瘤细胞系U251中AKT1和COX-2表达后,在体外对细胞侵袭转移的抑制作用,初步探讨其可能的作用机制。方法构建重组腺病毒载体rAd5-A-C同时搭载靶向AKT1和COX-2的shRNA干扰序列,将其转染至恶性胶质瘤细胞系U251细胞。Realtime PCR检测RNAi后目的基因mRNA的表达水平,Western Blot检测目的基因及MMP-2、MMP-9、TIMP-2的表达情况。酶联免疫吸附试验检测转染前后分泌到细胞外的MMP-2和MMP-9的浓度变化。划痕实验和Transwell实验评价肿瘤细胞转染前后的细胞侵袭能力的变化。结果rAd5-A-C转染组AKT1和COX-2的mRNA和蛋白表达均明显抑制;MMP-2、MMP-9表达下调,TIMP-2表达则上调。ELISA检测胞外MMP-2、MMP-9浓度明显减低;划痕实验显示细胞转移运动能力明显减弱,Transwell体外侵袭实验结果显示穿过细胞数明显减低(P0.001)。结论重组腺病毒介导的RNAi技术可以序列特异性地抑制U251细胞AKT1和COX-2的表达,在体外对U251细胞侵袭转移产生明显抑制作用,可能成为恶性胶质瘤治疗的新策略。 相似文献
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目的 探讨胶质瘤细胞LN229中RECK作为miR-21的调控靶点,在胶质瘤侵袭性生长中的作用.方法 将反义miR-21(AS-miR-21)寡核苷酸转染至人脑胶质瘤细胞LN229中.Real-time PCR检测LN229细胞中miR-21的表达量.荧光素酶实验检测miR-21对RECK的调控关系.Transwell实验评价LN229细胞侵袭能力的变化,应用Western blot检测细胞内MMP2/9和RECK蛋白水平的变化,ELISA实验检测培养基中活性MMP2/9的表达量,动物实验评价体内条件下肿瘤侵袭性的变化.结果 Real-time PCR显示转染组中miR-21的表达量与对照组相比下调60%.荧光素酶实验证明RECK是miR-21的靶点.Transwell实验证实胶质瘤细胞侵袭能力下降,Western blot和ELISA实验证实MMP2/9表达降低,动物实验及免疫荧光反映肿瘤侵袭性生长受抑制.结论 反义miR-21通过上调RECK的表达而抑制恶性胶质瘤细胞的侵袭性生长.Abstract: Objective To investigate the regulation of miR - 21 on invasion growth of human glioma cells by RECK.Method The human glioma LN229 cells were transfected with AS - miR - 21 or scrambled sequences by Lipofectamine2000.Real time PCR was conducted to detect the expression of miR-21.Luciferase experiment was performed to detect the relationship between miR-21 and RECK.The expression of RECK was evaluated by Western blot.The invasion ability was evaluated by transwell assay and subcutaneous models.Western Blot, ELISA and immunofluorescence were used to estimate the changes of MMP2/9.Results The expression of miR - 21 in LN229 cells decreased after transfection with AS-miR-21. It was proved that RECK was a direct target of miR -21 by luciferase experiment.Meanwhile, the high expression of RECK protein in AS - miR -21 group conformed its important function in this mechanism.Transwell assay demonstrated decreased invasion capability of LN229 cell lines transfected with AS- miR- 21.Western blot, ELISA, and immunofluorescence demonstrated the levels of MMP2/9 were down -regulated in AS -miR -21 group compared with control and scrambled group.Conclusions AS - miR -21 could depress the invasion of glioma cells owing to up - regulating the level of RECK which could inhibit MMP2/9 activities both in vitro and vivo. 相似文献
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ObjectiveTo study the inhibitory effect of knocking down miR-30a-5p on the U87 human glioma xenograft growth and its possible mechanism. MethodsNude mice bearing subcutaneous U87 human glioblastoma were established and treated with miR-30a-5p antisense oligonucleotides (AS-miR-30a-5p) subcutaneous injection. Tumor size was measured every other day until the observation period ended. Researchers executed the animals after the treatment, stripped tumor tissues and extracted RNA and protein. Real-time PCR were conducted to detect the expression of miR-30a-5p. The histopathological characteristics and proliferation and apoptosis biological characters (including SEPT7, PCNA, cyclinD1, MMP-2, apoptosis related factor P53, bcl-2 and caspase3)were evaluated by HE and immunohistochemical staining, Western blot analysis respectively, and the cell apoptosis was detected by TUNEL method.ResultsIn AS-miR-30a-5p treated group, the tumor growth was delayed and the final tumor volume was smaller than that in the control and scr-ODN treated group (F=7.167, P<0.05), and the expression of miR-30a-5p was knocked down. The expression of PCNA、cyclinD1 were significantly down-regulated while P53、SEPT7 and caspase3 up-regulated. Apoptotic index was increased significantly. ConclusionAs-miR-30a-5p suppresses the growth of U87 human gliomas xenografts significantly. Malignant phenotype of tumors are reversed to a considerable degree. Therefore, miR-30a-5p can be a candidate for targeted therapy of human glioma. 相似文献
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益气化痰方降脂及抗凝作用的实验研究 总被引:3,自引:0,他引:3
益气化痰方以治疗“中风不语,痰蒙清窍”的古代名方“涤痰汤”为基础化裁而成。研究以实验性高脂血症家兔为对象,观察了益气化痰方的降脂作用及其对凝血功能的影响,结果表明,益气化痰方能明显降低高脂血症家兔的血浆胆固醇(TH)、甘油三酯(TG),并使高密度脂蛋白——胆固醇含量增高(HDL-CH);延长血浆凝血酶原时间(PT)、凝血酶时间(TT)、白陶土部分凝血活酶时间(KPTT),显示出对凝血过程的抑制。由此提示,益气化痰方既能降低血脂,又可抗凝,认为这是其治疗心脑血管疾病,祛除痰浊,消除瘀滞,畅通血脉的作用机制之一。 相似文献
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反义miR-21抑制异种移植U251人脑胶质瘤生长的体内研究 总被引:2,自引:0,他引:2
目的 探讨敲低miR-21表达抑制裸鼠荷皮下U251人腩胶质瘤生长的疗效和机制. 方法 原位注射miR-21反义寡聚核苷酸(AS.miR-21)治疗裸鼠皮下荷U251人脑胶质瘤.定时测量肿瘤大小评估原位注射AS-miR-21治疗效果:使用Real time PCR和原位杂交方法鉴定治疗后miR-21表达水平下调;采用HE染色和免疫组织化学染色(PCNA、PTEN、MMPs、和Septins)评价治疗后肿瘤牛物学性状改变;TUNEL法检测肿瘤细胞凋亡. 结果 肿瘤生长曲线显示AS-miR-21治疗组肿瘤生长速度及体积小于空白对照与无义序列治疗组(F=52.458,P=0.000);Real-time PCR法:AS-miR-21治疗组miR-21表达下调为对照组的0.018±0.009:原位杂交显示AS-miR-21治疗组miR-21表达水平较对照与无义序列治疗组下调:组织病理学检测表明AS-miR-21治疗后肿瘤恶性度降低;TUNEL法检测可见AS-miR-21治疗组细胞凋亡数显著高于对照与无义序列治疗组(F=141.021,P=0.000).结论 以miR-21作为靶点抑制异种移植U251人脑胶质瘤生长,miR-21可能通过上调抑癌基因PTEN抑制胶质瘤的生长,可以作为人脑胶质瘤基因治疗的侯选靶点. 相似文献