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目的:研究宫颈癌患者新辅助化疗前后微小RNA-138(mi R-138)的表达及与化疗敏感性的关系。方法:选取2016年2月至2018年7月我院收治的宫颈癌患者18例为研究对象。所有患者均给予新辅助化疗,并根据治疗后的效果分为化疗有效组与化疗无效组。采用微阵列芯片技术分别检测两组患者化疗前后的mi R-138表达水平,同时采用Western blot技术检测mi R-138基因靶蛋白γH2AX的表达情况,分析患者化疗后mi R-138表达水平与临床病理特征的关系。结果:化疗有效组化疗后mi R-138△Ct值明显低于化疗前,且明显低于化疗无效组(P0.05),而化疗无效组化疗后mi R-138△Ct值与化疗前比较差异无统计学意义(P0.05)。化疗后两组靶蛋白γH2AX相对表达量均明显低于化疗前(P0.05),化疗有效组靶蛋白γH2AX相对表达量的差值显著低于化疗无效组(P0.05)。宫颈癌患者新辅助化疗后组织中mi R-138△Ct差值与肿瘤分化程度、浸润深度和淋巴结转移密切相关(P0.05),与年龄、FIGO临床分期无关(P0.05)。结论:新辅助化疗可以改变宫颈癌患者的mi R-138表达水平,且mi R-138的表达水平可能与化疗药物敏感性密切相关。  相似文献   
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目的:探讨miR-15a和miR-16-1模拟物对于人骨肉瘤细胞系SOSP-9607凋亡和增殖的影响。方法:将SOSP-9607细胞分为实验组和对照组。实验组分为miR-15a组、miR-16-1组、miR-15a+miR-16-1组。以miR-15a组为例,采用miR-15a模拟物(hsa-miR-15a mimics)上调SOSP-9607细胞内的miR-15a表达量。对照组分为阴性对照组和空白对照组。采用流式细胞仪测定细胞凋亡率,四甲基偶氮唑蓝(MTT)法测定细胞增殖,并计算细胞增殖效率。结果:通过统计学分析,实验组凋亡率与阴性对照组凋亡率相比明显增高(P<0.05);实验组的细胞增殖率明显低于对照组(P<0.05)。结论:上调SOSP-9607细胞内miR-15a和miR-16-1的表达量可促进SOSP-9607细胞的凋亡并抑制其增殖。  相似文献   
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Atherosclerosis is a kind of chronic cardiovascular disease, characterized by oxidized low-density lipoprotein (ox-LDL) accumulation in macrophage. Tanshinone IIA (Tan), a lipophilic pharmacologically activate compound from Salvia miltiorrhiza Bunge, has been indicated to exert cardioprotective roles. Nevertheless, the biological role of Tan and regulatory mechanism in atherosclerosis are not fully established. In present study, atherosclerosis model was established in THP-1-derived macrophages by treatment of ox-LDL. The adipogenesis was measured by Nile red staining. The expressions of inflammatory factors, microRNA-130b (miR-130b) and WNT5A were measured by quantitative real-time polymerase chain reaction or Western blot. The target association between miR-130b and WNT5A was explored via luciferase activity and RNA immunoprecipitation assay. The results showed that exposure of Tan inhibited ox-LDL-induced adipogenesis and expressions of interleukin-1β (IL-1β), IL-6, and tumor necrosis factor-alpha in THP-1-derived macrophages. miR-130b expression was decreased in THP-1-derived macrophages treated by ox-LDL and its overexpression attenuated adipogenesis as well as inflammatory response. miR-130b knockdown reversed the regulatory effect of Tan on adipogenesis and inflammatory response in THP-1-derived macrophages stimulated by ox-LDL. In addition, WNT5A acted as a functional target of miR-130b and inhibited by Tan and miR-130b. As a conclusion, Tan decreased the adipogenesis and inflammatory response by mediating miR-130b and WNT5A, providing a novel theoretical foundation for treatment of atherosclerosis.  相似文献   
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The current study was designed to explore the role and underlying mechanism of lncRNA taurine up-regulated gene 1 (TUG1) in cardiac hypertrophy. Mice were treated by transverse aortic constriction (TAC) surgery to induce cardiac hypertrophy, and cardiomyocytes were treated by phenylephrine (PE) to induce hypertrophic phenotype. Haematoxylin-eosin (HE), wheat germ agglutinin (WGA) and immunofluorescence (IF) were used to examine morphological alterations. Real-time PCR, Western blots and IF staining were used to detect the expression of RNAs and proteins. Luciferase assay and RNA pull-down assay were used to verify the interaction. It is revealed that TUG1 was up-regulated in the hearts of mice treated by TAC surgery and in PE-induced cardiomyocytes. Functionally, overexpression of TUG1 alleviated cardiac hypertrophy both in vivo and in vitro. Mechanically, TUG1 sponged and sequestered miR-34a to increase the Dickkopf 1 (DKK1) level, which eventually inhibited the activation of Wnt/β-catenin signalling. In conclusion, the current study reported the protective role and regulatory mechanism of TUG1 in cardiac hypertrophy and suggested that TUG1 may serve as a novel molecular target for treating cardiac hypertrophy.  相似文献   
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Objective: Long non-coding RNAs (lncRNAs) recently have been identified as influential indicators in a variety of malignancies. The aim of the present study was to identify a functional lncRNA LINC00488 and its effects on thyroid cancer in the view of cell proliferation and apoptosis.Methods: In order to evaluate the effects of LINC00488 on the cellular process of thyroid cancer, we performed a series of in vitro experiments, including cell counting kit-8 (CCK-8) assay, EdU (5-ethynyl-2′-deoxyuridine) assay, flow cytometry, transwell chamber assay, Western blot and RT-qPCR. The target gene of LINC00488 was then identified by bioinformatics analysis (DIANA and TargetScan). Finally, a series of rescue experiments was conducted to validate the effect of LINC00488 and its target genes on proliferation, migration, invasion and apoptosis of thyroid cancer.Results: Our findings revealed that LINC00488 was highly expressed in thyroid cancer cell lines (BCPAP, BHP5-16, TPC-1 and CGTH-W3) and promoted the proliferation, migration and invasion, while inhibited the apoptosis of thyroid cancer cells (BCPAP and TPC-1). The results of bioinformatics analysis and dual luciferase reporter gene assay showed that LINC00488 could directly bind to miR-376a-3p and down-regulated the expression level of miR-376a-3p. In addition, Paraoxonase-2 (PON2) was a target gene of miR-376a-3p and negatively regulated by miR-376a-3p. Rescue experiment indicated that LINC00488 might enhance PON2 expression by sponging miR-376a-3p in thyroid cancer.Conclusion: Taken together, our study revealed that lncRNA LINC00488 acted as an oncogenic gene in the progression of thyroid cancer via regulating miR-376a-3p/PON2 axis, which indicated that LINC00488-miR-376a-3p-PON2 axis could serve as novel biomarkers or potential targets for the treatment of thyroid cancer.  相似文献   
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Understanding of the functions of microRNAs in breast cancer and breast cancer stem cells have been a hope for the development of new molecular targeted therapies. Here, it is aimed to investigate the differences in the expression levels of let-7a, miR-10b, miR-21, miR-125b, miR-145, miR-155, miR-200c, miR-221, miR-222 and miR-335, which associated with gene and proteins in MCF-7 (parental) and MCF-7s (Mammosphere/stem cell-enriched population/CD44+/CD24-cells) cells treated with paclitaxel. MCF-7s were obtained from parental MCF-7 cells. Cytotoxic activity of paclitaxel was determined by ATP assay. Total RNA isolation and cDNA conversion were performed from the samples. Changes in expression levels of miRNAs were examined by RT-qPCR. Identified target genes and proteins of miRNAs were analyzed with RT-qPCR and western blot analysis, respectively. miR-125b was significantly expressed (2.0946-fold; p = 0.021) in MCF-7s cells compared to control after treatment with paclitaxel. Downregulation of SMO, STAT3, NANOG, OCT4, SOX2, ERBB2 and ERBB3 and upregulation of TP53 genes were significant after 48 h treatment in MCF-7s cells. Protein expressions of SOX2, OCT4, SMAD4, SOX2 and OCT4 also decreased. Paclitaxel induces miR-125b expression in MCF-7s cells. Upregulation of miR-125b may be used as a biomarker for the prediction of response to paclitaxel treatment in breast cancer.  相似文献   
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目的:探讨mi R-155对人椎间盘退变髓核细胞凋亡的影响及其作用机制。方法:首先构建慢病毒表达载体,在293T细胞中获得重组慢病毒,然后感染椎间盘退变髓核细胞得到稳定过表达细胞系,同时设置空载体和空白细胞组对照。用荧光显微镜观察慢病毒载体的标签蛋白GFP的表达,分别提取三组细胞总RNA,采用RT-q PCR方法检测mi R-155的表达;通过流式细胞术检测细胞凋亡,Western-Blot检测细胞中凋亡相关蛋白FADD、Caspase-3、Bcl-2及Bax的表达,JC-1试剂盒检测细胞线粒体膜电位的变化情况。结果:在荧光显微镜下,经慢病毒感染的过表达细胞系和空载体细胞系均出现绿色荧光,而空白细胞组未见绿色荧光;RT-qPCR结果显示构建的稳定过表达细胞系(GV369-miR-155-NP)中mi R-155的表达水平较高,且与空载体细胞系及空白细胞对照组均呈显著性差异(P0.05);与空载体组(GV369-NP)及空白细胞对照组相比,过表达组(GV369-miR-155-NP)细胞凋亡率显著降低(P0.05),FADD、Caspase-3、Bax的表达水平均明显下降,而Bcl-2表达水平显著增加(P0.05)。结论:mi R-155可能通过靶向结合Caspase-3和FADD阻止FasL-Fas途径或通过线粒体途径抑制人椎间盘退变髓核细胞凋亡。  相似文献   
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