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991.
992.
Non-small-cell lung cancer (NSCLC) is one of the main causes of death induced by cancer globally. However, the molecular aberrations in NSCLC patients remain unclearly. In the present study, four messenger RNA microarray datasets (GSE18842, GSE40275, GSE43458, and GSE102287) were downloaded from the Gene Expression Omnibus (GEO) database. Differentially expressed genes (DEGs) between NSCLC tissues and adjacent lung tissues were obtained from GEO2R and the overlapping DEGs were identified. Moreover, functional and pathway enrichment were performed by Funrich, while the protein–protein interaction (PPI) network construction were obtained from STRING and hub genes were visualized and identified by Cytoscape software. Furthermore, validation, overall survival (OS) and tumor staging analysis of selected hub genes were performed by GEPIA. A total of 367 DEGs (95 upregulated and 272 downregulated) were obtained through gene integration analysis. The PPI network consisted of 94 nodes and 1036 edges in the upregulated DEGs and 272 nodes and 464 edges in the downregulated DEGs, respectively. The PPI network identified 46 upregulated and 27 downregulated hub genes among the DEGs, and six (such as CENPE, NCAPH, MYH11, LRRK2, HSD17B6, and A2M) of that have not been identified to be associated with NSCLC so far. Moreover, the expression differences of the mentioned hub genes were consistent with that in lung adenocarcinoma and lung squamous cell carcinoma in the TCGA database. Further analysis showed that all the six hub genes were associated with tumor staging except MYH11, while only the upregulated DEG CENPE was associated with the worse OS of patients with NSCLC. In conclusion, the current study showed that CENPE, NCAPH, MYH11, LRRK2, HSD17B6, and A2M might be the key genes contributed to tumorigenesis or tumor progression in NSCLC, further functional study is needed to explore the involved mechanisms.  相似文献   
993.
Emerging evidence indicates that microRNAs play an important role in neural remodeling, including neurite growth, after acute spinal cord injury (ASCI). This study aims to identify the mechanism by which miR-92b-3p regulates neurite growth in vivo and in vitro. Adult Sprague–Dawley rats were selected to establish the ASCI model, and the expressions of miR-92b-3p and phosphate and tensin homolog deleted on chromosome ten (PTEN) were quantified at different time points. The interaction between miR-92b-3p and PTEN was further detected in the PC12 cell line and dual-luciferase reporter assay. Neurite growth proteins (GAP43 and NF-200) were assessed by western blotting after miR-92b-3p mimics treatment. The PTEN/AKT pathway-related proteins and their roles in miR-92b-3p regulation were also identified using western blotting and immunofluorescence in vitro through LY294002, an AKT inhibitor. The effect of miR-92b-3p was further determined in vivo according to the Basso-Beattie-Bresnahan (BBB) Scale and GAP43 and NF-200 expressions. miR-92b-3p was downregulated after ASCI, while PTEN showed a simultaneous opposing trend. Overexpression of miR-92b-3p downregulated PTEN expression and promoted phosphorylation of AKT, as well as the expression of GAP43 and NF-200 in PC12 cells. Furthermore, the dual-luciferase reporter assay revealed that miR-92b-3p exerted its effect by targeting PTEN's 3ʹ-untranslated regions and that this effect could be counteracted by AKT phosphorylation blocker LY294002 through western blotting and immunofluorescence. Moreover, miR-92b-3p could also improve the BBB scale as well as GAP43 and NF-200 expression levels in vivo. Collectively, these results indicate that miR-92b-3p promotes neurite growth and functional recovery through the PTEN/AKT pathway in ASCI.  相似文献   
994.
Ganoderma lucidum immunomodulatory protein (FIP-glu) is an active ingredient with potential immunoregulatory functions. The study was conducted to explore the immunomodulatory activities of recombinant FIP-glu (rFIP-glu) and its possible mechanism in macrophage RAW264.7 cells. In vitro assays of biological activity indicated that rFIP-glu significantly activated RAW264.7 cells and possessed proinflammatory and anti-inflammatory abilities. RNA sequencing analysis and Western blot analysis showed that macrophage activation involved PI3K/Akt and MAPK pathways. Furthermore, real-time quantitative polymerase chain reaction indicated that the PI3K inhibitor LY294002 blocked the messenger RNA (mRNA) levels of MCP-1 (CCL-2), the MEK1/2 inhibitor U0126 reduced the mRNA levels of TNF-α and MCP-1 (CCL-2), and the JNK1/2/3 inhibitor SP600125 prevented the upregulation of inducible nitric oxide synthase mRNA in rFIP-glu-induced cells. rFIP-glu did not mediate these inflammatory effects through a general pathway but rather through a different pathway for a different inflammatory mediator. These data imply that rFIP-glu possessed immunomodulatory activity in macrophages, which was mediated through PI3K/Akt and MAPK pathways.  相似文献   
995.
Intimal hyperplasia is an important cause of stenosis or occlusion after vascular injury. Circular RNAs (circRNAs) are known to be related to various cardiovascular diseases. However, the expression profile of circRNAs in the neointima has not been reported in detail. In this study, we established a rat common carotid artery (CCA) injury model. A microarray detection showed significant differences in circRNA expression between the normal and injured CCA. Real-time quantitative polymerase chain reaction verified the differences. We used bioinformatics to predict the microRNAs that possibly interact with the differentially expressed (DE) circRNAs and linked the potential functions of circRNAs to the target genes of the microRNAs. We believe that the DE circRNA in neointima may affect the differentiation, proliferation, and migration of vascular cells through a variety of target genes. The intervention or utilization of certain circRNAs should be a new method for preventing and treating intimal hyperplasia.  相似文献   
996.
997.
This study aims to reveal the regulatory mechanism of lncRNAs–miRNAs–mRNAs network during the proliferative phase of liver regeneration (LR). High-throughput sequencing technology was performed, and a total of 1,738 differentially expressed lncRNAs (DE lncRNAs), 167 known differentially expressed miRNAs (DE miRNAs), and 2,727 differentially expressed mRNAs were identified. Then, the target DE lncRNAs and DE mRNAs regulated by the same miRNAs were screened and a ceRNA regulatory network containing 32 miRNAs, 107 lncRNAs, and 270 mRNAs was constructed. Insulin signaling pathway, pyrimidine metabolism, axon guidance, carbohydrate digestion and absorption, and pyruvate metabolism were significantly enriched in the network. Through literature review and the regulatory relationship between lncRNAs and miRNAs, nine core lncRNAs were identified, which might play important roles during the proliferative phase of rat LR. This study analyzed lncRNA–miRNA–mRNA regulatory network for the first time during the proliferative phase of rat LR, providing clues for exploring the mechanism of LR and the treatment of liver diseases.  相似文献   
998.
【目的】在白念珠菌中建立一个快捷方便经济的基因敲除与筛选标记再循环的DNA操作系统。【方法】通过ExoIII介导的不依赖于连接酶的克隆策略,在异源筛选标记基因CmLEU2、CdHIS1和CdARG4基因的两侧分别插入了loxP位点,成为筛选标记基因盒扩增的模板。全基因合成了经过白念珠菌密码子优化的rTetR元件,并组装成Tet-on启动子。将密码子优化的重组酶Cre基因置于该启动子控制下。然后将他们插入筛选标记基因CdHIS1和CdARG4的CDS区域,形成筛选标记基因再循环载体。【结果】构建了3个用于白念珠菌基因敲除的侧翼含有loxP位点的筛选标记基因载体,以及2个含有Tet-on启动子控制的Cre酶的载体用于筛选标记基因的再循环。【结论】成功构建了一个白念珠菌中可诱导的基因敲除和筛选标记再循环的载体系统并成功应用于多个基因缺失株构建。这个系统有助于快速构建白念珠菌的单基因和多基因敲除菌株。  相似文献   
999.
自噬是真核生物中重要且高度保守的蛋白降解过程。在此过程中,细胞中的细胞器、长寿蛋白及其他大分子物质被双层膜的自噬体包裹并运送至降解细胞器中进行降解并重新利用。自噬在病原真菌诸如细胞分化、营养动态平衡以及致病性等各种细胞过程中起重要作用。在本综述中,我们简要介绍了自噬过程,并以人体病原真菌新生隐球菌为例介绍了病原真菌的有性生殖过程;同时我们也总结了目前模式病原真菌中自噬相关基因的研究情况以及自噬调控病原真菌无性和有性生殖的可能机理;最后我们总结全文并讨论了未来自噬调控真菌有性生殖机理研究的工作方向。  相似文献   
1000.
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