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131.
Circular RNA (circRNA) is involved in a wide range of life processes including tumorigenesis. However, the molecular mechanisms of circRNA in endometrial carcinoma (EC) carcinogenesis remain unclear. In the present study, we aimed to investigate the potential modulation of hsa_circ_0002577 on EC progression. Here, we showed that hsa_circ_0002577 expression was significantly upregulated in EC tissues, and high hsa_circ_0002577 expression was associated with advanced FIGO stage, lymph node metastasis, and poor overall survival rate of EC patients. In function assays, we demonstrated that hsa_circ_0002577 knockdown significantly reduced EC cells proliferation, migration, invasion ability in vitro and decreased tumor growth in vivo. In mechanism study, we revealed that hsa_circ_0002577 might act as a sponge for miR-197, and CTNND1 was revealed to be a target gene of miR-197. In addition, we revealed that the oncogenic effects of hsa_circ_0002577 were attributed to the regulation of miR-197/CTNND1/Wnt/β-catenin axis. Taken together, we indicated that hsa_circ_0002577 could play critical functions by hsa_circ_0002577/miR-197/CTNND1/Wnt/β-catenin signaling pathway, which served as a novel therapeutic application for EC treatment.  相似文献   
132.
Background: Circulating microRNAs (miRNA) are present in body fluids in stable, cell-free form. Likewise, these miRNAs can be identified in various stages of coronary artery disease (CAD) such as inflammation, endothelial dysfunction, proliferation and atherosclerosis among others. miRNA expression levels can be identified.

Aims and objectives: To determine the expression of circulating miRNAs (miR-126, miR-92, miR-33, miR-145 and miR-155) in CAD patients of Indian origin.

Material and methods: miRNA profiling analysis in blood plasma was performed by quantitative real-time-PCR (qRT-PCR) in 60 angiographically verified subjects including 30 CAD patients and 30 age- and gender-matched controls. Association between the expression of all five circulating miRNAs and clinical characteristics of patients with CAD were analysed using Medcalc statistics. The severity of CAD was assessed using SYNTAX score (SS).

Results: Expression of plasma miR-33 increased by 2.9 folds in CAD patients than in control group (p value ≥0.002) also it was found that miR-33 expression levels in mild cases (SS: ≤22) were significantly higher than CAD controls. There was a modest negative correlation between miR-33 and total cholesterol/high density lipoprotein ratio, triglycerides and very low density lipoprotein.

Conclusion: The study reports a significant association between increased levels of plasma miR-33 and CAD. Thus, plasma miR-33 appears to be a promising non-invasive biomarker, but requires further validation in a large cohort.  相似文献   

133.
Coagulation factor VIIa (FVIIa) belongs to a family of proteases being part of the stepwise, self-amplifying blood coagulation cascade. To investigate the impact of the mutation Met(298{156})Lys in FVIIa, we replaced the Gly(283{140})-Met(298{156}) loop with the corresponding loop of factor Xa. The resulting variant exhibited increased intrinsic activity, concurrent with maturation of the active site, a less accessible N-terminus, and, interestingly, an altered macromolecular substrate specificity reflected in an increased ability to cleave factor IX (FIX) and a decreased rate of FX activation compared to that of wild-type FVIIa. In complex with tissue factor, activation of FIX, but not of FX, returned to normal. Deconvolution of the loop graft in order to identify important side chain substitutions resulted in the mutant Val(158{21})Asp/Leu(287{144})Thr/Ala(294{152})Ser/Glu(296{154}) Ile/Met(298{156})Lys-FVIIa with almost the same activity and specificity profile. We conclude that a lysine residue in position 298{156} of FVIIa requires a hydrophilic environment to be fully accommodated. This position appears critical for substrate specificity among the proteases of the blood coagulation cascade due to its prominent position in the macromolecular exosite and possibly via its interaction with the corresponding position in the substrate (i.e. FIX or FX).  相似文献   
134.
摘要 目的:探讨circ_0001461对骨肉瘤细胞增殖和凋亡的影响及调控机制。方法:采用实时荧光定量聚合酶反应(qRT-PCR)检测检测circ_0001461在骨肉瘤组织和细胞中的表达水平。在U2OS和HOS细胞中转染sh-NC和sh-circ_0001461后,采用CCK8检测细胞增殖情况,流式细胞术检测细胞凋亡情况,qRT-PCR检测增殖相关分子Ki-67 mRNA的表达水平,Western Blot检测凋亡相关分子Cleaved-caspase-3蛋白的表达水平。采用双荧光素酶报告基因检测circ_0001461和miR-30a-5p的结合情况。结果:circ_0001461在骨肉瘤组织中的表达水平明显高于癌旁正常组织(P<0.05),circ_0001461在骨肉瘤细胞U2OS和HOS中的表达水平均明显高于成骨细胞NHOst(P<0.05)。低表达circ_0001461能够抑制骨肉瘤细胞U2OS和HOS的增殖和增殖相关分子Ki-67的表达(P<0.05);促进骨肉瘤细胞U2OS和HOS的凋亡和凋亡相关分子Cleaved-caspase-3蛋白的表达(P<0.05)。双荧光素酶结果显示circ_0001461能够靶向结合miR-30a-5p。低表达circ_0001461能够促进miR-30a-5p的表达(P<0.05),circ_0001461和miR-30a-5p在骨肉瘤组织中的表达呈负相关(P<0.05)。在U2OS细胞中共转染sh-circ_0001461和miR-30a-5p mimics后能够进一步加强单独转染sh-circ_0001461对U2OS细胞增殖和凋亡的影响(P<0.05);在HOS细胞中共转染sh-circ_0001461和miR-30a-5p inhibitors后能够逆转单独转染sh-circ_0001461对U2OS细胞增殖和凋亡的影响(P>0.05)。结论:circ_0001461在骨肉瘤组织和细胞中明显高表达,低表达circ_0001461能够靶向促进miR-30a-5p的表达进而抑制骨肉瘤细胞增殖和促进细胞凋亡。  相似文献   
135.
摘要 目的:探究血清miR-203、miR-217表达与急性髓系白血病(AML)患者预后的关系。方法:选择2010年4月至2014年4月我院诊治的101例AML患者作为AML组,AML组根据治疗效果进一步分为完全缓解组和复发组,选择同期在我院体检的101例健康者作为健康组。采用荧光定量PCR检测各组的血清miR-203、miR-217表达水平,分析血清miR-203、miR-217表达水平与患者临床病理特征的关系,采用Kaplan-Meier法分析不同血清miR-203、miR-217表达水平AML患者的预后。结果:与健康组相比,AML组的血清miR-203、miR-217表达水平明显更低(P<0.05)。与完全缓解组相比,复发组的血清miR-203、miR-217表达水平明显更低(P<0.05)。血清miR-203表达水平与AML患者白细胞计数相关(P<0.05),而血清miR-217表达水平与AML患者血小板计数相关(P<0.05)。血清miR-203相对高表达和miR-217相对高表达的AML患者5年生存率分别高于血清miR-203相对低表达和miR-217相对低表达患者(Log Rank miR-203 =17.870,Log Rank miR-217 =28.926,均P=0.000)。结论:血清miR-203、miR-217的表达水平与AML密切相关,检测血清miR-203、miR-217表达水平可能有助于评估AML患者的预后。  相似文献   
136.
《Reproductive biology》2022,22(1):100600
Circular RNAs (circRNAs) have been identified as critical regulators in human cancers, including cervical cancer (CC). However, the precise action of circ_0084904 in cervical carcinogenesis remains to be elucidated. The levels of circ_0084904, microRNA (miR)-802, and Mal, T cell differentiation protein 2 (MAL2) were checked by quantitative real-time PCR (qRT-PCR) or western blot. Ribonuclease R (RNase R) and subcellular localization assays were used to detect the stability and localization of circ_0084904, respectively. Cell colony formation ability was assessed by colony formation assay. Cell cycle and apoptosis were detected by flow cytometry. Cell migration and invasion abilities were gauged by transwell assay. Dual-luciferase reporter and RNA immunoprecipitation (RIP) assays were applied to determine the direct relationship between miR-802 and circ_0084904 or MAL2. The xenograft experiments were performed to evaluate the role of circ_0084904 in tumor growth in vivo. Circ_0084904 was markedly up-regulated in CC tissues and cell lines. Silencing endogenous circ_0084904 impeded cell colony formation, cell cycle progression, migration, invasion, epithelial-mesenchymal transition (EMT), and promoted apoptosis in vitro, as well as diminished tumor growth in vivo. Mechanistically, circ_0084904 targeted miR-802, and the effects of circ_0084904 silencing were mediated by miR-802. MAL2 was directly targeted and inhibited by miR-802, and MAL2 was a functional target of miR-802. Moreover, circ_0084904 modulated MAL2 expression via miR-802. Our study identified circ_0084904 as a novel oncogenic driver in CC depending on the modulation of the miR-802/MAL2 axis, establishing the notion that silencing of circ_0084904 might represent a promising targeted therapy for CC.  相似文献   
137.
《Reproductive biology》2022,22(2):100610
Accumulating evidence has verified that the aberrant expression level of miR-493?3p is often associated with the occurrence of numerous cancers. Nevertheless, the expression level and effect of this microRNA in ovarian cancer (OC) remain largely unclear. Therefore, the molecular function of miR-493?3p in OC progression was systematically investigated in this study.The expression of miR-493?3p and DPY30 was assessed by qRT-PCR. The protein expression level of DPY30 in cell lines was further assessed by western blot. Cell viability was respectively examined in vitro functional experiments including CCK-8 assay, EdU assay, wound healing assay, colony formation and apoptosis assays as well as the scratch test and transwell assay. Bioinformatics analysis and luciferase reporter assays were performed to predict and clarity of the correlation between miR-493?3p and DPY30.The expression of miR-493?3p was significantly reduced in OC tissues and cells. Functional experimental results showed that miR-493?3p suppressed cellular proliferation, migration, invasion, but promoted apoptosis in OC cells. Mechanistically, we also confirmed that DPY30 could be directly targeted by miR-493?3p based on bioinformatics and dual-luciferase reporter analysis. Rescue experiments results indicated that the inhibitory effect of miR-493?3p on cellular proliferation, migration and invasion and the promotive effect of miR-493?3p on apoptosis was abolished by DPY30 overexpression.Our findings demonstrated the antitumor effect of miR-493?3p through targeting DPY30 in ovarian cancer, indicating that miR-493?3p might represent a promising target for ovarian cancer diagnosis and treatment.  相似文献   
138.
《Reproductive biology》2022,22(1):100611
Long non-coding RNAs (lncRNAs) have been elucidated to play vital roles in the phenotype of trophoblast cells. Nevertheless, the effect of SNHG1 has not been investigated on trophoblast cells in recurrent spontaneous abortion (RSA). We aim to investigate the effect of SNHG1 on the phenotype of trophoblast cells during RSA. The RSA mice were established by mating female CBA/J mice with male DBA/2 mice. Microarray analysis was applied in RSA mice, and SNHG1 was identified as a significantly downregulated lncRNA. SNHG1 improved pregnancy outcome and reduced embryo resorption in RSA mice. Trophoblast cell proliferation, apoptosis, migration, and invasion were investigated by CCK8, EdU, TUNEL, wound healing, and Transwell assays. SNHG1 promoted proliferation, migration, and invasion of trophoblast cells, and reduced apoptosis. Mechanistically, SNHG1 bound to miR-183-5p in trophoblast cells. Moreover, miR-183-5p directly targeted ZEB2. Rescue experiment showed that ZEB2 silencing reversed the ameliorative effect of SNHG1 on pregnancy outcome and the promotion of trophoblast activity in RSA mice by impaired the Wnt/β-catenin pathway. In conclusion, we found that SNHG1 plays a critical role in the progression of RSA via miR-183-5p/ZEB2 and Wnt/β-catenin signaling. It has potential to be a therapeutic marker of RSA.  相似文献   
139.
140.
《Reproductive biology》2022,22(2):100637
Increasing evidence indicates that circular RNAs (CircRNAs) have an important role in human diseases, including polycystic ovary syndrome (PCOS). Recently, circ_0043533, a novel circRNA, was proposed to be involved in the progression of PCOS. However, its role in PCOS has not been explored. In this study, the expression levels of circ_0043533 and miR-1179 in ovarian granulosa cells (OGCs) were examined by qRT-PCR analysis. Moreover, knockdown of circ_0043533 in OGC lines COV434 and KGN, respectively, the cell viability, proliferation, apoptosis, and cycle-related markers of insulin-triggered OGCs were examined by CCK-8, EdU staining, flow cytometry, and western blot assays, respectively. The interaction between circ_0043533 and miR-1179 was examined by bioinformatics, dual-luciferase assay, and RNA immunoprecipitation. Besides, effects of the miR-1179 inhibitor on cell viability and apoptosis in OGC lines with circ_0043533 knockdown were also evaluated. OGCs and insulin-treated OGCs exhibited higher circ_0043533 levels in comparison to the IOSE80 cells. Additionally, knockdown of circ_0043533 remarkably inhibited the cell viability and proliferation and promoted the apoptosis of insulin-treated COV434 and KGN cells, respectively. Meanwhile, circ_0043533 knockdown could down-regulate the Bcl-2, CDK2, and Cyclin D1 expressions, and up-regulate the Bax levels. Furthermore, we demonstrated that circ_0043533 acted as a sponge to absorb miR-1179. Interestingly, miR-1179 inhibition remarkably attenuated the effect of circ_0043533 silence on cell proliferation and apoptosis in insulin-treated COV434 and KGN cells. Taken together, this study revealed that circ_0043533 knockdown restrained the malignant progression of PCOS via targeting miR-1179. Our data suggested that circ_0043533 would serve as a novel therapeutic target for PCOS.  相似文献   
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