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长链非编码RNA(LncRNA)是近十年来肿瘤领域分子机制研究的热点之一,被证实在生物体内对基因的表达具有调控作用,与肿瘤的发生与发展密切相关。结直肠癌是一种严重危害人类健康的恶性肿瘤,研究发现许多LncRNA在结直肠癌中表达失调。异常表达的LncRNA作为关键的调控因子,参与了多种生物学过程,影响肿瘤细胞的增殖和凋亡、侵袭转移及调节肿瘤耐药。研究LncRNA在肠癌中的作用机制可以为结直肠癌临床治疗提供一些新思路。此外,LncRNA还可作为一种潜在的生物标志物用于结直肠癌早期诊断及预后评估。 相似文献
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《Value in health》2020,23(9):1218-1224
ObjectivesAlthough numerous mapping algorithms from a non–preference-based measure to a target health utility measure have been developed and applied in cost-utility analyses (CUAs), conditions for a mapping algorithm to work well in a CUA are still unclear. In this research, we formulate the mapping problem as a missing data problem and clarify these conditions.MethodsWe defined a valid mapping algorithm based on the purpose of mapping (ie, not for prediction but for CUA), and derived a sufficient set of conditions for a valid mapping algorithm. We also conducted a simulation study to investigate properties of a mapping algorithm under situations where the conditions are satisfied and violated.ResultsThe derived sufficient conditions indicate that the complete overlap of the source measure with the target health utility measure is important and that a covariate that is omitted from a mapping algorithm but has an effect on the target health utility measure not captured by the source measure may invalidate a mapping algorithm. The conditions cannot be verified from data in a CUA but can be supported using external data. A simulation study showed that when at least 1 of the 3 conditions was violated, a mapping algorithm provided biased health utility estimates in a CUA, and that prediction accuracy did not necessarily reflect performance of a mapping algorithm in a CUA.ConclusionThe derived conditions provide a fundamental basis for better practices in developing and selecting a mapping algorithm. 相似文献
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目的探讨基因间长链非编码RNA 152(LINC00152)靶向调控微小RNA-103a-3p(miR-103a-3p)表达及对非小细胞肺癌(NSCLC)细胞增殖和侵袭迁移的影响。方法采用实时定量PCR(QPCR)检测正常肺上皮细胞BEAS-2B及NSCLC细胞(ANIP-973、NCI-H157、A549和NCI-H1975)的LINC00152水平。选取LINC00152水平最高的细胞分别转染LINC00152特异性小干扰RNA(si-LINC00152组)或无关序列(si-NC组),另设未转染细胞为对照组。QPCR检测LINC00152水平,活细胞计数CCK-8法、Transwell小室和划痕实验测定细胞增殖、侵袭和迁移能力,Western blotting检测基质金属蛋白酶(MMP)-2、MMP-9和第10号染色体缺失的磷酸酶及张力蛋白同源基因(PTEN)的水平;荧光素酶报告实验验证LINC00152靶向结合miR-103a-3p的能力。结果NSCLC细胞的LINC00152水平均高于BEAS-2B细胞(P<0.05),尤其是NCI-H1975细胞的最高。si-LINC00152组的LINC00152水平为0.352±0.087,低于对照组的1.058±0.219和si-NC组的1.126±0.139(P<0.05)。与si-NC组和对照组相比,si-LINC00152组NCI-H1975细胞转染48、72 h的增殖活力下降(P<0.05);si-LINC00152组的划痕愈合率和穿膜细胞数分别为(27.386±2.428)%和(78.840±5.031)个,低于si-NC组的(77.675±4.803)%和(179.208±13.264)个及对照组的(76.371±5.385)%和(174.003±15.678)个(P<0.05);与si-NC组和对照组相比,si-LINC00152组的MMP-2和MMP-9水平均降低,而PTEN水平升高(P<0.05)。对照组和si-NC组上述指标的差异无统计学意义(P>0.05)。双荧光素酶报告分析证实,miR-103a-3p模拟物降低了野生型LINC00152的荧光素酶活性(P<0.05),但对突变型无影响(P>0.05)。结论LINC00152在NSCLC细胞中高表达并发挥促癌作用,与NSCLC的迁移侵袭密切相关,LINC00152与miR-103a-3p间的相互作用在NSCLC靶向治疗中有一定潜能。 相似文献
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《Vaccine》2020,38(31):4783-4791
A novel coronavirus (CoV), Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), emerged in late 2019 in Wuhan, China and has since spread as a global pandemic. Safe and effective vaccines are thus urgently needed to reduce the significant morbidity and mortality of Coronavirus Disease 2019 (COVID-19) disease and ease the major economic impact. There has been an unprecedented rapid response by vaccine developers with now over one hundred vaccine candidates in development and at least six having reached clinical trials. However, a major challenge during rapid development is to avoid safety issues both by thoughtful vaccine design and by thorough evaluation in a timely manner. A syndrome of “disease enhancement” has been reported in the past for a few viral vaccines where those immunized suffered increased severity or death when they later encountered the virus or were found to have an increased frequency of infection. Animal models allowed scientists to determine the underlying mechanism for the former in the case of Respiratory syncytial virus (RSV) vaccine and have been utilized to design and screen new RSV vaccine candidates. Because some Middle East respiratory syndrome (MERS) and SARS-CoV-1 vaccines have shown evidence of disease enhancement in some animal models, this is a particular concern for SARS-CoV-2 vaccines. To address this challenge, the Coalition for Epidemic Preparedness Innovations (CEPI) and the Brighton Collaboration (BC) Safety Platform for Emergency vACcines (SPEAC) convened a scientific working meeting on March 12 and 13, 2020 of experts in the field of vaccine immunology and coronaviruses to consider what vaccine designs could reduce safety concerns and how animal models and immunological assessments in early clinical trials can help to assess the risk. This report summarizes the evidence presented and provides considerations for safety assessment of COVID-19 vaccine candidates in accelerated vaccine development. 相似文献
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