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Paclitaxel is a widely used chemotherapy drug for advanced laryngeal cancer patients. However, the fact that there are 20-40% of advanced laryngeal cancer patients do not response to paclitaxel makes it necessary to figure out potential biomarkers for paclitaxel sensitivity prediction. In this work, Hep2, a laryngeal cancer cell line, untreated or treated with lower dose of paclitaxel for 24 h, was applied to DNA microarray chips for gene and miR expression profile analysis. Expression of eight genes altered significantly following paclitaxel treatment, which was further validated by quantitative real-time PCR. Four up-regulated genes were ID2, BMP4, CCL4 and ACTG2, in which ID2 and BMP4 were implicated to be involved in several drugs sensitivity. While the down-regulated four genes, MAPK4, FASN, INSIG1 and SCD, were mainly linked to the endoplasmic reticulum and fatty acid biosynthesis, these two cell processes that are associated with drug sensitivity by increasing evidences. After paclitaxel treatment, expression of 49 miRs was significantly altered. Within these miRs, the most markedly expression-changed were miR-31-star, miR-1264, miR-3150b-5p and miR-210. While the miRs putatively modulated the mRNA expression of the most significantly expression-altered genes were miR-1264, miR-130a, miR-27b, miR-195, miR-1291, miR-214, miR-1277 and miR-1265, which were obtained by miR target prediction and miRNA target correlation. Collectively, our study might provide potential biomarkers for paclitaxel sensitivity prediction and drug resistance targets in laryngeal cancer patients.  相似文献   
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A subset of human breast cancer cell lines exhibits aberrant DNA hypermethylation that is characterized by hyperactivity of the DNA methyltransferase enzymes, overexpression of DNMT3b, and concurrent methylation-dependent silencing of numerous epigenetic biomarker genes. The objective of this study was to determine if this aberrant DNA hypermethylation (i) is found in primary breast cancers, (ii) is associated with specific breast cancer molecular subtypes, and (iii) influences patient outcomes. Analysis of epigenetic biomarker genes (CDH1, CEACAM6, CST6, ESR1, GNA11, MUC1, MYB, SCNN1A, and TFF3) identified a gene expression signature characterized by reduced expression levels or loss of expression among a cohort of primary breast cancers. The breast cancers that express this gene expression signature are enriched for triple-negative subtypes — basal-like and claudin-low breast cancers. Methylation analysis of primary breast cancers showed extensive promoter hypermethylation of epigenetic biomarker genes among triple-negative breast cancers, compared to other breast cancer subclasses where promoter hypermethylation events were less frequent. Furthermore, triple-negative breast cancers either did not express or expressed significantly reduced levels of protein corresponding to methylation-sensitive biomarker gene products. Together, these findings suggest strongly that loss of epigenetic biomarker gene expression is frequently associated with gene promoter hypermethylation events. We propose that aberrant DNA hypermethylation is a common characteristic of triple-negative breast cancers and may represent a fundamental biological property of basal-like and claudin-low breast cancers. Kaplan–Meier analysis of relapse-free survival revealed a survival disadvantage for patients with breast cancers that exhibit aberrant DNA hypermethylation. Identification of this distinguishing trait among triple-negative breast cancers forms the basis for development of new rational therapies that target the epigenome in patients with basal-like and claudin-low breast cancers.  相似文献   
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目的构建携带人miR302和增强型绿色荧光蛋白(EGFP)基因的慢病毒表达载体pFUM3GW。方法NheⅠ和NotⅠ双酶切pmiR302ApE以释放miR302,接着补平酶切位点而获连接用miR302;BamHⅠ酶切携带EGFP的慢病毒载体pFUGW,接着补平酶切产物,并去磷酸化而获连接用载体片段,最后使用DNA连接试剂盒(TaKaRa)中的SolutionI将其与连接用miR302连接,连接产物转化,次日挑选单菌落,PCR筛选正向阳性克隆,随后将选定的含有阳性克隆的单菌落摇菌,提取质粒并行酶切鉴定及对插入的miR302测序。所构建载体命名为pFUM3GW。获pFUM3GW后,按Invitrogen公司推荐的标准程序进行慢病毒包装和确认慢病毒是否成功生产;携带miR302和EGFP基因的慢病毒感染鼻咽癌细胞株C666-1、CNE1和5-8F以建立相应病毒感染体系。结果PCR、酶切和测序证实成功构建了pFUM3GW,按标准程序生产的携带miR302和EGFP基因的慢病毒上清高效率感染小鼠胚胎成纤维细胞(MEFs)及鼻咽癌细胞株C666-1、CNE1和5-8F。结论成功构建携带人miR302和EGFP基因的慢病毒表达载体pFUM3GW,为相关后续研究打下了良好基础。  相似文献   
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microRNA是一类近年来研究热门的微小RNA分子,在人类多种生理和病理过程中起重要的调节作用,其家族成员miR.155和循环系统疾病关系的研究日益深入而广泛,本文就miR.155和循环系统疾病的诊断、治疗、预后等多方面的关系及其作用机制作一综述。  相似文献   
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Most HCV‐infected patients regularly consume alcohol. Alcoholic liver disease (ALD) and chronic hepatitis C virus (HCV) infection together are the most common causes of liver disease worldwide. Although both factors independently cause liver disease, they synergistically promote rapid liver disease progression with devastating outcomes for patients. This review focuses on the prevalence, clinical characteristics and molecular pathophysiologic mechanisms of HCV infection associated with alcohol abuse. Recent findings have centred on the synergistic effect of alcohol and HCV on viral replication, hepatocyte apoptosis, oxidative stress, alcohol‐induced ‘leaky gut’, miR‐122 and immune dysregulation. Clinical and basic research findings presented here summarize key scientific findings with the aim of highlighting potential areas for new therapies and identifying ways of optimizing current treatments for alcoholics with HCV infection.  相似文献   
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