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1.
AIM: To investigate the expression and function of circular RNA_0000231 (circ_0000231) in non-small-cell lung cancer (NSCLC). METHODS: RT-qPCR was used to detect the expression of circ_0000231 in the NSCLC tissues and cell lines. circ_0000231 small interfering RNA (si-circ_0000231) or negative control siRNA of circ_0000231 (NC) was transfected into the NSCLC cells. The proliferation and apoptosis of the NSCLC cells were detected by CCK-8 assay, colony formation assay and flow cytometry, respectively. The expression of cyclin D1 (CCND1) and anti-apoptotic protein Bcl-2 were determined by RT-qPCR and Western blot. RESULTS: The expression of circ_0000231 in the NSCLC tissues and cell lines was significantly up-regulated compared with precancerous tissues and lung epithelial cells BEAS-2B (P<0.05). After transfection of NSCLC cells with si-circ_0000231, the cell viability, colony formation numbers were significantly decreased, and the apoptotic rate in si-circ_0000231 group was significantly increased as compared with NC group (P<0.01). In addition, the results of RT-qPCR and Western blot showed that transfection of si-circ_0000231 inhibited the expression of CCND1 and Bcl-2 (P<0.01). CONCLUSION: The expression of circ_0000231 is significantly increased in the NSCLC tissues and cells. Knock-down of circ_0000231 expression significantly inhibits the proliferation of NSCLC cells.  相似文献   
2.
为研究microRNA-124-3p(miR-124-3p)对H1N1亚型猪流感病毒(swine influenza virus,SIV)感染小鼠所致肺损伤的调控作用,本试验构建miR-124-3p腺病毒表达载体,通过小鼠尾部静脉注射法构建miR-124-3p差异表达小鼠模型,试验分3组:过表达组、抑制组和对照组。48 h后,各组小鼠鼻腔接种H1N1亚型SIV,每只105 EID50(50 μL)。连续观察14 d,计算小鼠平均体重变化率、观察病理切片并测定相关炎症因子IL-1β、TNF-α和IL-6 mRNA相对表达量。结果显示,已成功将pre-miR序列及其sponge序列插入腺病毒的穿梭质粒,并将其共转染293A细胞。实时荧光定量PCR检测证实,与对照组相比,过表达组和抑制组小鼠黑色素瘤细胞miR-124-3p表达水平分别极显著升高(P<0.01)和显著降低(P<0.05),表明成功构建腺病毒表达载体。过表达组、抑制组和对照组小鼠体重变化率分别为-5.5%、-12.4%和-8.6%。抑制组和对照组均可见肺泡壁增厚,其间有多量淋巴细胞浸润,部分肺泡内出现纤维蛋白渗出,且抑制组病理变化更为严重,肺泡中还有大量的红细胞浸润;而过表达组仅有少量的淋巴细胞浸润,肺脏组织较正常。与对照组相比,过表达组检测的炎症因子IL-1β、TNF-α和IL-6 mRNA表达水平均显著降低(P<0.05);抑制组炎症相关炎症因子mRNA表达水平均显著升高(P<0.05)。本试验结果表明,miR-124-3p对H1N1亚型SIV感染小鼠所致的肺脏炎症因子的表达具有抑制作用,同时能减轻肺脏病理损伤。  相似文献   
3.
Primary pulmonary neoplasia is relatively uncommon in cats and generally has a poor prognosis. In this multicenter, retrospective study of 57 cats with pulmonary neoplasia, the most frequent presenting signs were anorexia/inappetence (39%) and cough (37%). The pulmonary tumors were considered to be incidental findings in 9% cats. In computed tomographic (CT) images, primary pulmonary tumors appeared as a pulmonary mass in 55 (96%) cats and as a disseminated pulmonary lesion without a defined mass in two (4%) cats. Most pulmonary tumors were in the caudal lobes, with 28 (49%) in the right caudal lobe and 17 (30%) in the left caudal lobe. CT features associated with pulmonary tumors included mass in contact with visceral pleura (96%), irregular margins (83%), well‐defined borders (79%), bronchial compression (74%), gas‐containing cavities (63%), foci of mineral attenuation (56%), and bronchial invasion (19%). The mean (range) maximal dimension of the pulmonary masses was 3.5 cm (1.1–11.5 cm). Additional foci of pulmonary disease compatible with metastasis were observed in 53% cats. Pleural fluid was evident in 30% cats and pulmonary thrombosis in 12% cats. The histologic diagnoses were 47 (82%) adenocarcinomas, six (11%) tumors of bronchial origin, three (5%) adenosquamous cell carcinomas, and one (2%) squamous cell carcinoma. In this series, adenocarcinoma was the predominant tumor type, but shared many features with less common tumor types. No associations were identified between tumor type and CT features. Prevalence of suspected intrapulmonary metastasis was higher than in previous radiographic studies of cats with lung tumors.  相似文献   
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5.
观察不同剂量纳米氧化铈颗粒染毒后对大鼠血清超氧化物歧化酶(SOD)活力和丙二醛(MDA)含量的影响及大鼠肺组织GRP78蛋白表达情况,探讨其导致肺损伤的作用机制。将粒径为35nm±3nm的纳米氧化铈颗粒悬液以不同剂量(100mg/kg、400mg/kg)给大鼠气管滴注,染毒28d后,测定大鼠血清中SOD活力、MDA含量及肺组织GRP78蛋白表达情况。与对照组相比,高低剂量纳米氧化铈染毒组大鼠血清中SOD活力及MDA含量均无明显改变(P0.05),GRP78蛋白表达均显著增高(P0.05)。纳米氧化铈染毒大鼠所致肺损伤与内质网应激有关,与氧化应激的关系有待进一步研究。  相似文献   
6.
The involvement of the lung during the septic systemic inflammatory response elicited by administration of lipopolysaccharide (LPS) was investigated. Eight-week-old male Sprague–Dawley rats were injected i.p. with 15 mg/kg LPS. After 24 h, the lungs were excised to evaluate the cellular responses to LPS. Matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF) analysis revealed that type VI collagen (ColVI) was extremely upregulated during sepsis in the rat lung within the first 24 h of LPS administration. Upregulation of ColVI protein and its mRNA was demonstrated by Western blot analysis, real time PCR, and immunohistochemistry. To the best of our knowledge, this is the first report demonstrating the activation of ColVI in the rat lung at the early stage of systemic inflammation. Activation of ColVI might be involved in sepsis-mediated lung fibrosis at an early stage.  相似文献   
7.
FGF4已经被证明是癌基因,它涉及肿瘤的生长和转移,为了解FGF4的表达与肿瘤微环境的关系。我们利用FGF4抗体通过免疫组化对一名肺癌患者癌旁,癌组织,癌组织小鼠移植瘤,二次移植瘤以及原代培养的细胞爬片进行FGF4检测,探究其表达差异。通过对比癌组织与对照组(癌旁组织),FGF4在癌巢中高表达;同样,移植瘤与二次移植瘤的癌巢中与癌旁组织比较,FGF4表达相对较高;但是将癌组织进行原代培养后,免疫组化检测细胞爬片FGF4,发现仅有5%±0.21%的肿瘤细胞表达FGF4,对照蛋白Cytokine作为肿瘤标记物,则在100%的肿瘤细胞中表达。研究提示免疫组化检测到FGF4在体内和体外表达不同,提示肿瘤细胞FGF4的表达与肿瘤微环境调控密切相关,肿瘤微环境对肿瘤细胞的FGF4的调控有着重要作用。  相似文献   
8.
AIM:To investigate the effect of proline-spirooxindole on the viability and apoptosis of human non-small-cell lung cancer A549 cells. METHODS:The effect of proline-spirooxindole on the viability of A549 cells was determined by CCK-8 assay. The apoptosis was analyzed by flow cytometry. The effects of proline-spirooxindole on the expression of PARP and p53 and the phosphorylation of mTOR were determined by Western blot. RESULTS:After A549 cells were treated with proline-spirooxindole (25, 50 and 100 mg/L), the cell viability was decreased (P<0.01) compared with DMSO control group. The apoptotic rate was increased compared with DMSO control group (P<0.01). The protein expression of p53 was up-regulated, the increased apoptotic protein cleaved PARP was observed, and the phosphorylation of mTOR was inhibited (P<0.01). CONCLUSION:Proline-spirooxindole inhibits the viability of A549 cells and induces apoptosis, which may be related to the phosphorylation of mTOR.  相似文献   
9.
AIM: To investigate the effects of high mobility group A2(HMGA2) gene knockdown on the cell viability, apoptosis, collagen synthesis and oxidative stress of human embryonic lung fibroblast (HELF) induced by transforming growth factor-β1 (TGF-β1). METHODS: The HELF were divided into blank group, TGF-β1 group,negative control (NC) group and HMGA2 siRNA(si-HMGA2) group. The protein levels of HMGA2, AKT and p-AKT were determined by Western blot. The cell viability and apoptotic rate was analyzed by MTT assay and flow cytometry,respectively. The mRNA expression of collagen I (COL-Ⅰ) and COL-Ⅲ was detected by RT-qPCR. DCFH-DA was used to detect the content of reactive oxygen species (ROS). RESULTS: Compared with blank group, the protein levels of HMGA2 and p-AKT, the cell viability, the mRNA expression of COL-Ⅰ and COL-Ⅲ in TGF-β1 group were significantly increased, but the apoptotic rate and ROS level were significantly decreased (P<0.05). Compared with TGF-β1 group, the protein levels of HMGA2 and p-AKT, the cell viability, the mRNA expression of COL-Ⅰ and COL-Ⅲ in si-HMGA2 group were significantly decreased, but the apoptotic rate and ROS level were significantly increased (P<0.05). CONCLUSION: Knockdown of HMGA2 gene expression decreases the viability and collagen synthesis, and promotes apoptosis and ROS production of human embryonic lung fibroblasts induced by TGF-β1. The mechanism may be related to down-regulation of PI3K/AKT signaling pathway.  相似文献   
10.
AIM: To explore the target relationship between microRNA-140-3p (miR-140-3p) and programmed cell death ligand 1 (PD-L1) and their effect on the viability, migration and invasion of non-small-cell lung cancer A549 cells.METHODS: RT-qPCR was used to detect the miR-140-3p expression in HLF-1, A549 and H1299 cells, and then the A549 cells with the most significant difference were selected as the subsequent research object. TargetScan software and dual-luciferase reporter assay were performed to predict and confirm the target relationship between miR-140-3p and PD-L1. RT-qPCR and Western blot were used to determine the effects of miR-140-3p mimic and inhibitor on PD-L1 expression level. MTT assay was used to detect the viability of A549 cells. Transwell assay was performed to detect the migration and invasion abilities of the A549 cells.RESULTS: miR-140-3p was significantly down-regulated in the A549 cells and H1299 cells (P<0.05). Transfection with miR-140-3p mimic decreased the expression of PD-L1 and inhibited the viability, migration and invasion of the A549 cells. Transfection with pcDNA3.0-PD-L1 reversed the inhibitory effect of miR-140-3p on the viability, migration and invasion of the A549 cells.CONCLUSION: miR-140-3p inhibits the viability, migration and invasion of A549 cells by targeting PD-L1.  相似文献   
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