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51.
Hepatocellular cancer (HCC) has been reported to belong to one of the highly vascularized solid tumours accompanied with angiogenesis of human umbilical vein endothelial cells (HUVECs). KDM5A, an attractive drug target, plays a critical role in diverse physiological processes. Thus, this study aims to investigate its role in angiogenesis and underlying mechanisms in HCC. ChIP-qPCR was utilized to validate enrichment of H3K4me3 and KDM5A on the promotor region of miR-433, while dual luciferase assay was carried out to confirm the targeting relationship between miR-433 and FXYD3. Scratch assay, transwell assay, Edu assay, pseudo-tube formation assay and mice with xenografted tumours were conducted to investigate the physiological function of KDM5A-miR-433-FXYD3-PI3K-AKT axis in the progression of HCC after loss- and gain-function assays. KDM5A p-p85 and p-AKT were highly expressed but miR-433 was down-regulated in HCC tissues and cell lines. Depletion of KDM5A led to reduced migrative, invasive and proliferative capacities in HCC cells, including growth and a lowered HUVEC angiogenic capacity in vitro. Furthermore, KDM5A suppressed the expression of miR-433 by demethylating H3K4me3 on its promoterregion. miR-433 negatively targeted FXYD3. Depleting miR-433 or re-expressing FXYD3 restores the reduced migrative, invasive and proliferative capacities, and lowers the HUVEC angiogenic capacity caused by silencing KDM5A. Therefore, KDM5A silencing significantly suppresses HCC tumorigenesis in vivo, accompanied with down-regulated miR-433 and up-regulated FXYD3-PI3K-AKT axis in tumour tissues. Lastly, KDM5A activates the FXYD3-PI3K-AKT axis to enhance angiogenesis in HCC by suppressing miR-433.  相似文献   
52.
Prostate cancer is the second most frequent malignancy in men worldwide, and its incidence is increasing. Therefore, it is urgently required to clarify the underlying mechanisms of prostate cancer. Although the long non-coding RNA LINC00115 was identified as an oncogene in several cancers, the expression and function of LINC00115 in prostate cancer have not been explored. Our results showed that LINC00115 was significantly up-regulated in prostate cancer tissues, which was significantly associated with a poor prognosis for prostate cancer patients. Functional studies showed that knockdown LINC00115 inhibited cell proliferation and invasion. In addition, LINC00115 served as a competing endogenous RNA (ceRNA) through sponging miR-212-5p to release Frizzled Family Receptor 5 (FZD5) expression. The expression of miR-212-5p was noticeably low in tumour tissues, and FZD5 expression level was down-regulated with the knockdown of LINC00115. Knockdown LINC00115 inhibited the Wnt/β‑catenin signalling pathway by inhibiting the expression of FZD5. Rescue experiments further showed that LINC00115 inhibits prostate cancer cell proliferation and invasion via targeting miR-212-5p/ FZD5/ Wnt/β-catenin axis. The present study provided clues that LINC00115 may be a promising novel therapeutic target for prostate cancer patients.  相似文献   
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54.
下丘脑Kiss1神经元产生的神经肽kisspeptin通过影响促性腺激素释放激素的分泌,参与青春期的启动、生殖系统的成熟以及排卵等过程的神经内分泌调节。Kiss1基因的表达受到包括多种反式调控因子及表观遗传的调控。预测与前期研究表明,miR-92a-3p、miR-25-3p的种子序列能够与Kiss1的3′-UTR直接结合,抑制Kiss1的表达。为进一步研究miR-92a-3p、miR-25-3p在Kiss1表达调控中的作用,本研究分别构建了对miR-92a-3p、miR-25-3p具有抑制作用的特异性吸附海绵载体:sponge-miR-92a和sponge-miR-25,以实现miRNA的功能缺失。流式细胞术和双荧光素酶报告基因系统分别证实,这2个海绵载体均能够非常有效地吸附外源性或内源性靶miRNA。sponge-miR-92a和sponge-miR-25载体被进一步包装成慢病毒LV-sponge-miR-92a和LV-sponge-miR-25。实时荧光定量PCR结果显示,经LV-sponge-miR-92a和LV-sponge-miR-25感染的下丘脑原代神经元细胞中,Kiss1表达水平均显著上调(P<0.05);将LV-sponge-miR-92a注射到下丘脑后,雌性小鼠阴门开启时间明显提前(P<0.05);下丘脑注射LV-sponge-miR-92a和LV-sponge-miR-25扰乱了雌性小鼠的正常动情周期。综上所述,成功构建了能够有效吸附miR-92a-3p、miR-25-3p的海绵载体,证明它们在解除miR-92a-3p、miR-25-3p对Kiss1的抑制中的作用,下丘脑注射海绵对雌性小鼠的阴门开启时间和动情周期均产生一定程度的影响,提示miR-92a-3p、miR-25-3p可能在青春期的启动和生殖成熟过程中发挥重要的作用。  相似文献   
55.
Myocardial fibrosis (MF) is one of the basic causes of many cardiovascular diseases. Noncoding RNAs (ncRNAs), including microRNA (miRNA) and long noncoding RNA (lncRNA), have been reported to play an indispensable role in MF. The current work is focused on investigating the biological role of lncRNA taurine upregulation gene 1 (TUG1) in activating cardiac myofibroblasts as well as the underlying mechanism. The outcome revealed that after myocardial infarction TUG1 expression increased and miR-133b expression decreased in the rat model of MF. The expression level of TUG1 increased following AngII treatment in cardiac myofibroblast. TUG1 knockdown inhibited the Ang-II induced cardiac myofibroblast activation and TUG1 overexpression increased proliferation and collagen generation of cardiac myofibroblasts. Bioinformatic prediction programs predicted that TUG1 had MRE directly combined with miR-133b seed sequence, luciferase activity, and RIP experiments indicated that TUG1, acted as a sponger and interacted with miR-133b in cardiac myofibroblasts. Furthermore, a target of miR-133b was CTGF and CTGF knockdown counteracted the promotion of MF by miR-133b knockdown. Collectively, our study suggested that TUG1 mediates CTGF expression by sponging miR-133b in the activation of cardiac myofibroblasts. The current work reveals a unique role of the TUG1/miR-133b/CTGF axis in MF, thus suggesting its immense therapeutic potential in the treatment of cardiac diseases.  相似文献   
56.
Non-small cell lung cancer (NSCLC) is the main reason of cancer linked mortality and around 80% of cases diagnosed in advanced stage. Therefore current study designed to evaluate the deregulation of miRNA-194 and miRNA-192 in different body fluid of Non small cell lung cancer participants. Present study recruited newly diagnosed histopathologically confirmed. It was observed that the 40% NSCLC participants showed elevated miR-194 expression and 60% NSCLC participants showed reduced miR-194 expression in serum sample while in Bronchial wash, only 20% NSCLC participants showed elevated miR-194 expression while 80% showed reduced miR-194 expression (p = 0.003). It was found that the 54% NSCLC participants showed elevated miR-192 expression and 55% NSCLC participants showed reduced miR-192 expression in serum sample while In Bronchial wash sample, only 25% NSCLC participants showed high miR-192 expression while 75% showed low miR-192 expression (P = 0.0004). Expression of miR-194 was significantly associated with TNM stages (p < 0.0001, p < 0.0001), distant organ metastases (p < 0.0001, p < 0.0001), pathological grade (p = 0.0009, p = 0.0005) among serum sample and bronchial wash sample. Same observation was found with expression of miR-192 and it was significantly associated with TNM stages (p < 0.0001, p < 0.0001), distant organ metastases (p < 0.0001, p < 0.0001), pathological grade (p = 0.006, p = 0.001) among serum sample and bronchial wash sample. It was observed that the NSCLC participants who had high serum based miR-194 expression showed 22 months of overall median survival while low expression of serum based miR-194 expression showed 18 months of overall median survival. Present study suggests that decreased expression of miR-194 and miR-192 was significantly associated with different clinical features of NSCLC cases. However, significantly higher number of NSCLC cases showed low expression of miR-194 and miR-192 in bronchial lavage sample. Decreased poor overall survival was found to be associated with bronchial wash sample with respect to low miR-194 and miR-192 expression while NSCLC participants showed better overall survival with high miR-194 and miR-192 expression. This suggested decreased expression of miR-192 and miR-194 expression could be the potential prognostic marker among NSCLC participants.  相似文献   
57.
ObjectiveMounting evidence demonstrates that long non-coding RNA (lncRNA) is dysregulated in breast cancers. This study was designed to detect the influences and regulatory mechanism of lncRNA PDCD4-AS1 in triple-negative breast cancer (TNBC).MethodsqRT-PCR and Western blot were utilized to investigate the expression levels of PDCD4-AS1, miR-10b-5p and IQGAP2 in TNBC tissues and cells. Online software and luciferase reporter gene system were employed to testify the interactions among these molecules. Loss and gain of function of PDCD4-AS1, miR-10b-5p or IQGAP2 were performed before MTT and colony formation assay, TUNEL staining in addition to Transwell and scratch assays were applied to measure the cell biological functions.ResultsIn this work, PDCD4-AS1 and IQGAP2 were lowly expressed while miR-10b-5p was strongly expressed in TNBC tissues and cells. PDCD4-AS1 or IQGAP2 overexpression effectively attenuated TNBC cell proliferation, migration and invasion, and increased the apoptosis rate, while this effect was abandoned in response to miR-10b-5p mimics transfection. miR-10b-5p bound to IQGAP2 and acted as a downstream target of PDCD4-AS1.ConclusionOur findings identified lncRNA PDCD4-AS1 as a tumor suppressor in TNBC by regulating IQGAP2 expression via miR-10b-5p, giving a novel insight into the regulatory mechanism of PDCD4-AS1 in the pathogenesis of TNBC.  相似文献   
58.
Cytokines and chemokines trigger complex intracellular signaling through specific receptors to mediate immune cell recruitment and activation at the sites of infection. CX3CL1 (Fractalkine), a membrane-bound chemokine also capable of facilitating intercellular interactions as an adhesion molecule, contributes to host immune responses by virtue of its chemoattractant functions. Published studies have documented increased CX3CL1 expression in target tissues in a murine model of spotted fever rickettsiosis temporally corresponding to infiltration of macrophages and recovery from infection. Because pathogenic rickettsiae primarily target vascular endothelium in the mammalian hosts, we have now determined CX3CL1 mRNA and protein expression in cultured human microvascular endothelial cells (HMECs) infected in vitro with Rickettsia rickettsii. Our findings reveal 15.5 ± 4.0-fold and 12.3 ± 2.3-fold increase in Cx3cl1 mRNA expression at 3 h and 24 h post-infection, coinciding with higher steady-state levels of the corresponding protein in comparison to uninfected HMECs. Since CX3CL1 is a validated target of microRNA (miR)-424-5p (miR-424) and our earlier findings demonstrated robust down-regulation of miR-424 in R. rickettsii-infected HMECs, we further explored the possibility of regulation of CX3CL1 expression during rickettsial infection by miR-424. As expected, R. rickettsii infection resulted in 87 ± 5% reduction in miR-424 expression in host HMECs. Interestingly, a miR-424 mimic downregulated R. rickettsii-induced expression of CX3CL1, whereas an inhibitor of miR-424 yielded a converse up-regulatory effect, suggesting miR-424-mediated regulation of CX3CL1 during infection. Together, these findings provide the first evidence for the roles of a host microRNA in the regulation of an important bifunctional chemokine governing innate immune responses to pathogenic rickettsiae.  相似文献   
59.

Background

The microRNAs let-7 g and miR-221 have been demonstrated to be related to the glucose metabolism. This study assessed the serum levels of these two microRNAs in subjects with and without metabolic syndrome (MetS).

Results

The serum microRNA levels were detected in 102 subjects aged 40 to 80 years who were recruited from the general population. The status of MetS was defined by the Adult Treatment Panel III (ATP III) criteria modified for Asians. Subjects with histories of cardiovascular diseases or who were receiving treatment with hypoglycemic or lipid-lowering agents were excluded. The levels of both circulating microRNAs (let-7 g and miR-221) were higher in subjects with MetS (p = 0.004 and p = 0.01, respectively). The sex-specific analysis showed that the difference was more prominent in women (for both miRNAs, p < 0.05 in women and p > 0.1 in men). In the female subjects, increased expression of both microRNAs was associated with an increased number of MetS risk components (p = 0.002 for let-7 g and p = 0.022 for miR-221). Moreover, the elevation of serum let-7 g was significantly associated with a low level of high-density lipoprotein cholesterol (p = 0.022) and high blood pressure (p = 0.023). In contrast, the miR-221 level was not associated with any individual MetS risk component.

Conclusions

The circulating levels of let-7 g and miR-221 displayed a female-specific elevation in individuals with metabolic syndrome.  相似文献   
60.
Abstract

MicroRNAs exert their biologic effects by targeting specific mRNAs for degradation or translational inhibition. MicroRNA-mediated regulation is complex, potentially affecting expression of the host gene, related enzymes within the same pathway or apparently distinct targets. miR-107 is found to be implicated in the pathogenesis of some diseases. This review was performed to sum up the role of miR-107 and its signaling pathways in renal diseases.  相似文献   
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