ObjectiveTo investigate the changes of lung function after exposure to fine particulate matter (PM2.5) for 60 days and the expression of miR-146 in mice.MethodsThirty SPF BALB/c mice were treated with noninvasive tracheal instillation of fine particulate matter suspension at different doses (2.5 mg/kg, 5.0 mg/kg, 10.0 mg/kg) for 2 months (two times one week), the blank group and normal saline group were set as control groups. The mice were examined and killed on the next day after the last instillation. Histopathological changes of the lungs, pro-infammatory factors levels in the lung tissues, pulmonary functions and the relative expression of miR-146a and miR-146b in the lung tissues were detected.ResultsPeak inspiratory flow (PIF) and peak expiratory flow (PEF) were decreased significantly after PM2.5 exposure, however, lung resistance increased and maximal voluntary ventilation reduced from the general tendency without significant difference. Hematoxylin-eosin stain showed lymphocyte infiltration and macrophage infiltration by phagocytic particles, alveolar spacer widening, inflammatory response increased with the increase of PM2.5 exposure dosage. Pro-infammatory factors as interleukin-6 in the bronchoalveolar lavage fluid, interferon-γ and tumor necrosis factor-α in the lung homogenate were increased significantly by enzyme linked immunosorbent assay. The relative expressions of miR-146a and miR-146b were up-regulated remarkablely in treatment groups compared to the control group by real-time fluorescence quantitative polymerase chain reaction, which had negative relationships with PIF and PEF.ConclusionsThe lung function of mice decreases significantly after exposure to fine particulate matter, and the expression of miR-146 is up-regulated.
Considering the low accuracy of prediction in the positive samples and poor overall classification effects caused by unbalanced sample data of MicroRNA (miRNA) target, we proposes a support vector machine (SVM)-integration of under-sampling and weight (IUSM) algorithm in this paper, an under-sampling based on the ensemble learning algorithm. The algorithm adopts SVM as learning algorithm and AdaBoost as integration framework, and embeds clustering-based under-sampling into the iterative process, aiming at reducing the degree of unbalanced distribution of positive and negative samples. Meanwhile, in the process of adaptive weight adjustment of the samples, the SVM-IUSM algorithm eliminates the abnormal ones in negative samples with robust sample weights smoothing mechanism so as to avoid over-learning. Finally, the prediction of miRNA target integrated classifier is achieved with the combination of multiple weak classifiers through the voting mechanism. The experiment revealed that the SVM-IUSW, compared with other algorithms on unbalanced dataset collection, could not only improve the accuracy of positive targets and the overall effect of classification, but also enhance the generalization ability of miRNA target classifier.
ObjectiveTo investigate the impact and mechanism of over-expression microRNA-92a (miR-92a) in clinicopathologic feature and prognosis of patients with colorectal cancer (CRC). MethodsThe expression levels of miR-92a and phosphatase and tensin homologue (PTEN) gene in 108 cases of colorectal cancer tissues were detected by using real-time fluorescent quantitative PCR (RT-PCR), and they were categorized as low or high in relation to the median value. Then the association between different levels of miR-92a gene expression and clinicopathologic feature and prognosis of CRC patients were evaluated. Moreover, the relationship between the expressions of miR-92a and PTEN gene were analyzed. ResultsHigh expression of miR-92a not only associated with lymph node metastasis (χ2=8.045, P=0.007), distant metastasis (χ2=5.708, P=0.030), and TNM staging (χ2=6.366, P=0.019) of CRC patients, but also related to the down-regulated of PTEN gene expression (χ2=21.333, P < 0.001). However, up-regulated miR-92a expression was negatively correlated with age, gender, tumor size, tumor location, depth of invasion and tumor differentiation. In addition, Kaplan-Meier survival curves showed that over-expression of miR-92a and low-expression of PTEN gene could potentially predict poor overall survival of CRC patients. ConclusionThe high expression of miR-92a can lead to a poor clinical prognosis of CRC patients through decreasing the expression level of PTEN gene.
Vascular endothelial cell(VEC) is a kind of simple squamous epithelium lined on the inner surface of blood vessels. VEC is an important barrier between the blood and tissue and it also plays a key role in regulating inflammation, thrombosis, endothelial cells mediated vasodilatation and endothelial regeneration. These processes should be controlled by a variety of complex mechanism which requires us to find out. With results of the researches in vascular endothelial cell function, the important roles that microRNA in vascular endothelial cell function draws more and more researchers' attention. MicroRNAs control gene expression in post-transcriptional level and affect the function of endothelial cells. This review focuses on the research progress on regulatory mechanism of microRNA to endothelial cell inflammation, thrombosis, vasodilation and endothelium regeneration.
ObjectiveTo systematically evaluate the clinical value of miRNA-1 in the diagnosis of acute myocardial infarction (AMI) patients.MethodsWe searched PubMed, EMbase, Cochrane Library, CNKI, Wangfang, VIP, etc databases to identify literature about miRNA-1 in the diagnosis of AMI. Quality of the included literature was assessed by (quality assessment for diagnostic accuracy studies-2, QUADAS-2). The indices of pooled sensitivity (Sen), specificity (Spe), positivity likelihood ratio (PLR), negative likelihood ratio (NLR), diagnosis odds ratio (DOR), and the area under the summary receiver operating characteristic (SROC) curve were pooled using MetaDisc 1.4 software.ResultsA total of 12 articles were included. According to the different populations of miRNA-1 to be tested, subgroup analysis of healthy people (7 articles) and non-AMI disease groups (5 articles) was conducted. The results showed that AMI compared with healthy people, the pooled Sen was 0.78 with 95%CI 0.73 to 0.82, Spe was 0.88 with 95%CI 0.83 to 0.91 of miRNA-1 in the diagnosis of AMI. AUC of SROC curve was 0.911 2. Comparison of AMI and non-AMI patients, the pooled Sen was 0.59 with 95%CI 0.54 to 0.64, Spe was 0.74 with 95%CI 0.68 to 0.79 of miRNA-1 in the diagnosis of AMI. AUC of SROC curve was 0.743 2.ConclusionMiRNA-1 has a certain value in the diagnosis of AMI. It has an advantage in identifying AMI and patients with other systemic diseases, and can be combined with other biomarkers to diagnose AMI.
Objective To review the regulation of microRNA-17-92 cluster on bone development, remodeling, and metabolism. Methods The related literature was reviewed. The clinical genetic phenotype, animal experiment, and cell research were illustrated so as to explore the possible regulatory mechanisms. Results MicroRNA-17-92 cluster is involved in physiological normal organs development, pathological neoplasm occurrence, and development. Recently, studies have shown that microRNA-17-92 cluster constitutes an intricate molecular signaling network with its upstream transcription factors and downstream targeting proteins, which controls bone development, remodeling, and metabolism exquisitely. Conclusion Present fundamental researches have certain understanding of the regulatory mechanisms of microRNA-17-92 cluster on bone development, remodeling, and metabolism. However, the exact mechanisms under these processes remain unknown.
Objective To investigate the effect of microRNA-27a (miR-27a) on the apoptosis of human lung adenocarcinoma cells A549 induced by lipopolysaccharide (LPS) by regulating the phosphatidylinositol-3-kinase (PI3K)/protein kinase B (AKT) pathway, and its mechanism is discussed preliminarily. Methods The complementary binding sites of miR-27a and phosphatidylinositol-3 kinase catalytic subunit delta (PIK3CD) were analyzed by Starbase and verified by double luciferase. The A549 cells were divided into normal group, LPS group, LPS+miR-27a mimic negative control group, LPS+miR-27a mimic group, LPS+miR-27a mimic+PI3K activator group. In the LPS+miR-27a mimic negative control group, LPS+miR-27a mimic group and LPS+miR-27a mimic+PI3K activator group, the cells were transfected with miR-27a mimic negative control, miR-27a mimic and miR-27a mimic, respectively, and were cultured for 6 h. After that, the cells were cultured in complete medium for 24 h, and then, except for the normal group, the cells in the other groups were stimulated with 10 mg/L LPS for 24 h, and the PI3K activator 740 Y-P was added to the LPS+miR-27a mimic+PI3K activator group, and cells in normal group were cultured in complete medium for the same time. Real-time quantitative polymerase chain reaction was used to detect the expression level of miR-27a in cells; cell counting kit 8 was used to detect cell proliferation; Hoechst33342 staining and flow cytometry was used to detect apoptosis; autophagy of A549 cells was observed by transmission electron microscope; Western blot was used to detect the expression of PIK3CD, phosphorylated-AKT (p-AKT), B-cell lymphoma-2 (Bcl-2), Bcl-2-associated X protein (Bax), cleaved caspase-3 and microtubule-associated protein 1 light chain 3 II (LC3II) protein. Results There was a binding site between miR-27a and PIK3CD, which was verified by double luciferase. Compared with those in normal group, the expression level of miR-27a, proliferation rate and protein expression level of Bcl-2 in LPS group and LPS+miR-27a mimic negative control group were lower (P<0.05), the apoptosis rate, protein expression levels of PIK3CD, p-AKT, Bax, cleaved caspase-3, LC3Ⅱ were higher (P<0.05); compared with those in LPS group and LPS+miR-27a mimic negative control group, the expression level of miR-27a, proliferation rate and protein expression level of Bcl-2 in LPS+miR-27a mimic group were higher (P<0.05), the apoptosis rate, protein expression levels of PIK3CD, p-AKT, Bax, cleaved caspase-3, LC3Ⅱ were lower (P<0.05); compared with those in LPS+miR-27a mimic group, the expression level of miR-27a and proliferation rate in LPS+miR-27a mimic+PI3K activator group were lower (P<0.05), the apoptosis rate, protein expression levels of PIK3CD, p-AKT, cleaved caspase-3, LC3Ⅱ were higher (P<0.05). The number of cells in the normal group was more, the cells were closely arranged, the nucleus size was uniform, and the organelle structure was normal; in LPS group and LPS+miR-27a mimic negative control group, cells became round, nuclei pyknosis, formed clumps, and showed multiple round autophagic vesicles of different sizes; the number of nuclear pyknotic cells in LPS+miR-27a mimic group decreased, and the number of nuclear pyknotic cells in LPS+miR-27a mimic+PI3K activator group increased compared with LPS+miR-27a mimic group, a small number of circular autophagic vesicles were observed, but the number was different. Conclusion Overexpression of miR-27a can inhibit PI3K/Akt pathway and reduce LPS induced apoptosis of human lung adenocarcinoma cells A549, which may be related to the reduction of autophagy.
Objective To investigate the effects of X-ray dose on the expressions of microRNA-221 （miR-221） and phosphatase and a tensin homolog deleted from chromosome10 （PTEN） in human colorectal carcinoma （CRC） cells. Methods Human CRC-derived cell line， Caco2， was cultured conventionally. The cells were divided into five groups and exposed to different doses of X-ray （0， 2， 4， 6， and 8 Gy） respectively. The total RNA and protein of the Caco2 cells were extracted after irradiation， and the miR-221 and PTEN mRNA expressions were detected by real-time RT-PCR.Moreover， the protein alteration of PTEN in Caco2 cells was detected by Western-blot analysis. Results The radiation dose of X-ray significantly affected the expressions of miR-221 and PTEN protein in human Caco2 cells in a dose-depen-dent manner. Moreover， the miR-221 expression level was up-regulated gradually with the increase of irradiation dose， on the contrary， the PTEN protein expression level was down-regulated gradually （P＜0.01）. Conclusion The radiation dose can affect the miR-221 and PTEN protein expression pattern in CRC cells.
At present, there are relatively many clinical gene studies. microRNA -215 (miR-215) is a miRNA induced by p53. It exists in animals and humans. miR-215 can exist not only in tumor tissues, but also in blood, urine and feces. miR-215 is abnormally expressed in a variety of tumors and plays a role in promoting and inhibiting cancer. Therefore, miR-215 may provide a new research direction for tumor diagnosis, treatment and prognosis. This paper reviews the expression of miR-215 as a oncogene and tumor suppressor gene in tumors and in non tumors.
ObjectiveTo observe the inhibitory effect of lentivirus (LV)-mediated miR-191 on the proliferation and angiogenesis of human retinal vascular endothelial cells (hREC) cultured in vitro.MethodsThe hREC cell lines were cultured in vitro and divided into control group, hypoxia group, LV-empty vector (LV-vector) group, and LV-miR-191 (LV-191) group. The LV-vector group and LV-191 group were transferred to the corresponding lentiviral vector respectively. Flow cytometry was used to detect cell transfection efficiency. Cell Counting Kit-8 (CCK-8) test was used to detect cell proliferation ability. Scarification test and invasion chamber (Transwell) test were used to detect cell migration ability. Matrigel test was used to detect cell lumen formation ability. Real-time quantitative polymerase chain reaction (qPCR) was used to detect the relative expression of miR-191 and relative mRNA expression of its downstream target genes p21, vascular endothelial growth factor (VEGF), cell division protein kinase (CDK) 6, cyclin-D1 (Cyclin D1). Independent sample t test was used for pairwise comparison. ResultsThe results of flow cytometry showed that the transfection efficiency of cells in the control group and the LV-191 group were 0.615% and 99.400%, respectively. The results of CCK-8, scarification, Transwell and Matrigel test showed that, compared with the control group, the number of cell proliferation (t=6.130, 4.606), the cell mobility (t=4.910, 6.702), the number of stained cells on the microporous membrane (t=7.244, 6.724) and the lumen formation ability cells (t=8.345, 9.859) were significantly increased in the hypoxia group and the LV-vector group (P<0.01), while the LV-191 group showed completely opposite performance (t=14.710, 6.245, 5.333, 5.892; P≤0.01). The qPCR test results showed that, compared with the control group and the LV-vector group, the relative expression of miR-191 mRNA in the cells of the LV-191 group was significantly up-regulated (t=44.110, 42.680), the relative expression of Cyclin D1 mRNA (t=29.940, 14.010) and CDK6 mRNA (t=15.200, 7.645) decreased significantly, and the difference were statistically significant (P<0.01); the relative expression of p21 mRNA increased, however, the difference was not statistically significant (t=2.013, 2.755; P>0.05). There was no significant difference in the relative expression of VEGF mRNA in the 4 groups of cells (F=0.966, P>0.05). ConclusionsLV-191 can inhibit the proliferation, migration and tubing of hREC by up-regulating p21 and down-regulating CDK6 and Cyclin D1.