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991.
Angiogenesis is an important process in atherosclerosis. ErbB2 was proved to have an important role in vascular development, but it is still unclear whether Erbin expresses in vessels as well as its location and function in the vessels. In the current study, we investigated the location and function of Erbin in human umbilical veins. The human umbilical veins were prepared, and immunofluorescent analysis was performed to determine the expression of Erbin. Human umbilical vein endothelial cells (HUVECs) were cultured and the lentivirus (LV) containing Erbin RNAi was also prepared. After transfection with the lentivirus, CCK-8 assay and Annexin V-PI assay were used for cell proliferation and apoptosis, respectively. Cell migration was studied using the scratch wound healing assay and the transwell assay. The capillary-like tube formation assay was performed to illustrate the effect of Erbin on HUVEC tube formation. Expression of signaling pathway molecules was assessed with Western blot. The immunofluorescent analysis suggested that Erbin expressed in human umbilical veins and the majority of the Erbin is strongly colocalized in endothelial cells. Although knockdown of Erbin did not affect HUVEC proliferation and apoptosis, it significantly suppressed HUVEC migration and tubular structure formation. Erbin knockdown showed no effect on the ERK1/2 and Smad2/3 signaling pathways but significantly promoted Smad1/5 phosphorylation and nuclear translocation. Ablation of the Smad1/5 pathway decreased the effects of Erbin on endothelial cells. Erbin is mainly localized in endothelial cells in human umbilical veins and plays a critical role in endothelial cell migration and tubular formation via the Smad1/5 pathway.  相似文献   
992.
Colorectal cancer is considered as the fourth leading reason of cancer-linked deaths worldwide. However, our knowledge about its pathogenic mechanism remains inadequate. MicroRNA 32 (miR-32), a member of small noncoding RNAs, has been found vital roles in tumorigenesis. This study studied its functions and underlying mechanism in colorectal cancer. The experiment revealed the obvious upregulation of miR-32 in colorectal cancer tissues and six cancer cell lines, compared with normal tissues and cells. Moreover, miR-32 upregulation reduced cell apoptosis and promoted cell proliferation and migration, while its downregulation displayed opposite effects. Dual luciferase reporter assays proved that miR-32 bound to the 3′-untranslated region (3′-UTR) of OTU domain containing 3 (OTUD3), suggesting that miR-32 directly targeted OTUD3. Further experiments demonstrated that overexpression of miR-32 could reduce the expression level of OTUD3. Furthermore, OTUD3 silence promoted proliferation and motility and decreased apoptosis for HCT116 cells and restored partly miR-32-mediated cell proliferation, migration, and antiapoptosis for colon cancer. Therefore, our study indicated that miR-32 enhanced cell proliferation and motility abilities, and inhibited apoptosis by directly targeting OTUD3 in colon cancer cells, which implied that miR-32 was hopeful to be a biomarker or target used for diagnosis and therapy of colon cancer.  相似文献   
993.
Lung adenocarcinoma is a major form of non–small-cell lung cancer that frequently strikes nonsmokers. The disease is often diagnosed at a late stage and the 5-year survival rate is very low. Although previous studies found many somatic alterations associated with lung adenocarcinoma, the molecular basis of the development and progression of the disease is not well understood. We found that long noncoding RNA (lncRNA) cancer susceptibility candidate 2 (CASC2), a putative tumor suppressor, was downregulated in both patient adenocarcinoma tissues and cultured lung cancer cells. Its tumor suppression function seemed to be dependent on its binding to miR-4735-5p. Changing the levels of CASC2 and miR-4735-3p in the cultured adenocarcinoma cells could affect the malignant phenotypes as well as growth of tumors derived from the cells injected into nude mice. Furthermore, the lncRNA and miR-4735-3p interplay likely the suppressed tumor growth through the downstream mammalian target of rapamycin signaling pathway. The results have revealed molecular details that may be critical for the development of lung adenocarcinoma, opening opportunities for the development of novel, and therapeutic tools.  相似文献   
994.
995.
Background/Aims: Fibroblast growth factor 21 (FGF21) plays a protective role in ischemia/reperfusion induced cardiac injury. However, the exact molecular mechanism of FGF21 action remains unclear. This study was designed the protective effect of FGF21 on the heart and its mechanism. Method: Adenovirus vector expressing FGF21 or control β-galactosidase was injected into the myocardium of mice. Myocardial injury was observed by tissue staining and immunohistochemical staining. The expression level of caspases-3 and galectin-3 in myocardial cells were observed by immunoblotting. Then, hypoxia-induced cell model was established. Small interfering RNA (SiRNA) and plasmid were transfected into H9c2 using Lipofectamine 2000 reagent (Invitrogen). The expression levels of galectin-3, ECM and cystatin-3 in cells were observed by immunoblotting, and the relationship between fibroblast growth factor 21 and galectin-3 was analyzed. Result: Cell test in vitro showed that FGF21 could inhibit apoptosis and decrease the expression of ECM (ColIaI, fibronectin, and alpha-SMA) under hypoxia. Western blot data showed that hypoxia-induced cell damage increased galectin-3 levels, while FGF21 decreased galactose lectin-3 levels. In addition, inhibition of galactose agglutinin-3 expression by siRNA enhanced the cardioprotective effect of FGF21, while overexpression of galectin-3 reduced the cardioprotective effect of fibroblast growth factor 21. Conclusion: FGF21 may be a novel therapy for hypoxia-induced cardiac injury by regulating the expression of galectin-3.  相似文献   
996.
Aberrant expression of long noncoding RNAs (lncRNAs) contributes to all phenotypes of cancer including metastasis, which is a major cause of death in many advanced malignancies. One particular lncRNA, H19, is found to be a crucial player in cancer progression by modulating multiple microRNAs (miRNAs). In this study, we screened miRNAs possibly associated with H19 using lung carcinoma cell lines and patient with lung cancer tissues, and selected one possible hit, hsa-miR-6515-3p, to perform in vitro functional assays. Its inhibition leads to decreased proliferation and migration of SPC-A1 lung cancer cells and is in good correlation with H19-knockdown groups. These results indicate that H19 may be an epigenetic regulator of miR-6515-3p, and its dysregulation may contribute to lung cancer progression and metastasis.  相似文献   
997.
Glioma is the most aggressive malignant tumor in the adult central nervous system. Abnormal long noncoding RNA (lncRNA) FOXD2-AS1 expression was associated with tumor development. However, the possible role of FOXD2-AS1 in the progression of glioma is not known. In the present study, we used in vitro and in vivo assays to investigate the effect of abnormal expression of FOXD2-AS1 on glioma progression and to explore the mechanisms. FOXD2-AS1 was upregulated in glioma tissue, cells, and sphere subpopulation. Upregulation of FOXD2-AS1 was correlated with poor prognosis of glioma. Downregulation of FOXD2-AS1 decreased cell proliferation, migration, invasion, stemness, and epithelial-mesenchymal transition (EMT) in glioma cells and inhibited tumor growth in transplanted tumor. We also revealed that FOXD2-AS1 was mainly located in cytoplasm and microRNA (miR)-185-5p both targeted FOXD2-AS1 and CCND2 messenger RNA (mRNA) 3′-untranslated region (3′-UTR). miR-185-5p was downregulated in glioma tissue, cells, and sphere subpopulation. Downregulation of miR-185-5p was closely correlated with poor prognosis of glioma patients. In addition, miR-185-5p mimics decreased cell proliferation, migration, invasion, stemness, and EMT in glioma cells. CCND2 was upregulated in glioma tissue, cells, and sphere subpopulation. Upregulation of CCND2 was closely correlated with poor prognosis of glioma patients. CCND2 knockdown decreased cell proliferation, migration, invasion, and EMT in glioma cells. In glioma tissues, CCND2 expression was negatively associated with miR-185-5p, but positively correlated with FOXD2-AS1. FOXD2-AS1 knockdown and miR-185-5p mimics decreased CCND2 expression. Inhibition of miR-185-5p suppressed FOXD2-AS1 knockdown-induced decrease of CCND2 expression. Overexpression of CCND2 suppressed FOXD2-AS1 knockdown-induced inhibition of glioma malignancy. Taken together, our findings highlight the FOXD2-AS1/miR-185-5p/CCND2 axis in the glioma development.  相似文献   
998.
In aquaculture, feeding is essential for the maintenance of metabolic processes and homoeostasis of fish. However, fasting acts as a stressor. In this study, we investigated the effect of circadian rhythm under various LED wavelengths [blue (460 nm), green (520 nm) and red (630 nm)] and two light intensities (0.3 and 0.6 W m?2) over a 9-days period in the olive flounder (Paralichthys olivaceus). We analysed clock genes like period 2 (Per 2) and cryptochrome 1 (Cry 1), and serotonin and arylalkylamine-N-acetyltransferase 2 (AANAT 2), which control circadian rhythms. Per 2, Cry 1, serotonin and AANAT 2 were significantly decreased during the starvation period compared to the normal feeding group. Nevertheless, their levels increased in the groups exposed to green- and blue LED light during the experimental period. These results confirmed that green and blue wavelengths are effective in maintaining the circadian rhythm in olive flounder.  相似文献   
999.
Recognition of specific molecule signatures of microbes, including pathogens, induces innate immune responses in plants, as well as in animals. Analogously, a nematode pheromone, the ascaroside ascr#18, induces hallmark plant defences including activation of (a) mitogen‐activated protein kinases, (b) salicylic acid‐ and jasmonic acid‐mediated defence signalling pathways and (c) defence gene expression and provides protection to a broad spectrum of pathogens. Ascr#18 is a member of an evolutionarily conserved family of nematode signalling molecules and is the major ascaroside secreted by plant–parasitic nematodes. Here, we report the effects of ascr#18 on resistance in four of the major economically important crops: maize, rice, wheat and soybean to some of their associated pathogens. Treatment with low nanomolar to low micromolar concentrations of ascr#18 provided from partial to strong protection in seven of eight plant–pathogen systems tested with viruses, bacteria, fungi, oomycetes and nematodes. This research may have potential to improve agricultural sustainability by reducing use of potentially harmful agrochemicals and enhance food security worldwide.  相似文献   
1000.
Little is known about what determines the nuclear matrix or how its reorganization is regulated during mitosis. In this study we report on a monoclonal antibody, mAb2A, which identifies a novel nuclear structure in Drosophila embryos which forms a diffuse meshwork at interphase but which undergoes a striking reorganization into a spindle-like structure during pro- and metaphase. Double labelings with α-tubulin and mAb2A antibodies demonstrate that the microtubules of the mitotic apparatus co-localize with this mAb2A labeled structure during metaphase, suggesting it may serve a role in microtubule spindle assembly and/or function during nuclear division. That the mAb2A-labeled nuclear structure is essential for cell division and/or maintenance of nuclear integrity was directly demonstrated by microinjection of mAb2A into early syncytial embryos which resulted in a disintegration of nuclear morphology and perturbation of mitosis. © 1996 Wiley-Liss, Inc.  相似文献   
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