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排序方式: 共有1224条查询结果,搜索用时 797 毫秒
1.
Zheyuan Wang Zhiheng Shi Lu Zhang Huihan Zhang Yawu Zhang 《Pathology, research and practice》2019,215(3):499-505
Profilin 1 (PFN1) is a critical actin-regulatory protein; however, its functional role in hepatocellular carcinoma (HCC) progression remains to be further elucidated. In the present study, we observed that the expression levels of PFN1 were significantly decreased in HCC tissues and cell lines. Low PFN1 expression was significantly correlated with aggressive clinicopathological characteristics and poor prognosis of HCC patients. Further in vitro experiments demonstrated that overexpression of PFN1 remarkably inhibited the proliferation, migration, invasion and EMT of HCC cells. Moreover, we also found that PFN1 was a direct target gene of miR-19a-3p, and in HCC tissues, and there was a significantly inverse correlation between PFN1 mRNA and miR-19a-3p expression. Collectively, our results showed that PFN1 functions as a tumor suppressor in HCC, and might serve as a diagnostic and therapeutic target for HCC patients. 相似文献
2.
Behavioral and autonomic responses to intermittent social stress: differential protection by clonidine and metoprolol 总被引:2,自引:2,他引:0
The present study investigated physiological and pharmacological characteristics of socially stressed animals. Specifically, we examined (1) to what degree autonomic and behavioral stress reactions during intermittent confrontations between an intruder male adult Long-Evans rat with an aggressive resident undergo habituation, and (2) to what extent the defeat-experienced animal can be protected against these stress reactions with clonidine or metoprolol, two adrenergic agents with clinical anxiolytic effects. We developed an acute social stress situation that consisted of initially placing an experimental rat as an intruder into the homecage of a resident while the resident was not present, thereafter permitting brief physical agonistic interactions with the reintroduced resident until the intruder was forced into a submissive supine posture and emitted ultrasonic vocalizations (USV), and eventually exposing the intruder to the resident's threats for one hour, while being shielded from potentially injurious attacks (threat encounter). Over the course of the initial 4-weekly threat encounters the acute tachycardia but not the hyperthermic stress responses decreased in magnitude. Following the first three threat encounters core temperature (Tc) was significantly elevated for at least 3 h. The Tc was already elevated when the repeatedly defeated intruder was confronted with the olfactory cues of the resident's cage. This conditioned anticipatory hyperthermia developed in the course of the first three confrontations and was paralleled by a decrease in exploratory and motor behavior and by an increase in defensive behaviors and in both types of USV emitted in the low (20–30 kHz) and the high (31–70 kHz) frequency range. Clonidine (0.01–0.1 mg/kg, IP), an
2-adrenergic agonist and metoprolol, a -adrenergic blocker (1.0–10.0 mg/kg, IP), dose-dependently prevented the tachycardic response to stress. Only clonidine, but not metoprolol, also attenuated the rise in T0 during the 1-h agonistic interaction. Clonidine decreased those aspects of motor behavior (e.g. rearing, walking) that are of lesser cost for the individual but maintained high levels of defensive reactions and increased the duration of low USV. The high doses of clonidine (0.06, 0.1 mg/kg) attenuated the homeostatic regulation and sedated the intruder while exposed to threats during a social confrontation. The absence of attenuation of the high level of defensive behavior and the prolonged low USV suggest a stress intensification by the higher doses of clonidine. In conclusion, after the fourth encounter, the autonomic, behavioral and vocal response pattern prior to and during repeated weekly confrontations show no evidence for habituation for the following 6 weeks. Moreover, adrenergic therapeutic agents that are applied to treat symptoms of anxiety block the tachycardic response but may actually intensify defensive behavior and certain stress vocalizations. 相似文献
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目的:对胰腺导管腺癌样本进行基因分析,筛选与胰腺导管腺癌相关的microRNA(miRNA),并初步分析目标miRNA与胰腺癌转化生长因子-β1(TGF-β1)信号通路的相关性。方法:收集在海南省中医院住院的胰腺导管癌患者术前外周静脉血血清标本19份,健康体检人群的外周静脉血血清标本21份作为非胰腺导管癌对照组。利用GCBI(Gene-Cloud Biotechnology Information)数据平台筛选与胰腺导管腺癌样本有关的基因并对其进行生物信息学分析,将筛选出的基因作为研究对象,用real-time PCR和蛋白质印迹法验证该基因在胰腺导管腺癌中的表达。通过改变胰腺导管腺癌细胞中该基因的表达水平观察其与TGF-β1之间的关系。结果:通过聚类分析和基因功能富集分析筛选出miRNA-21为胰腺导管癌相关基因。MiRNA-21在胰腺导管腺癌患者体内高表达。在miRNA-21过表达的PANC-1细胞中,TGF-β1表达受到抑制;但当miRNA-21的表达受到抑制时,TGF-β1的表达明显上升。结论:MiRNA-21在胰腺导管腺癌患者体内高表达,可调控TGF-β1的表达,从而参与胰腺导管腺癌的发生发展。 相似文献
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【目的】研究microRNA-30a-5p(miR-30a-5p)对人宫颈癌Hela细胞上皮-间质转化功能的影响及其相关机制。【方法】宫颈癌Hela细胞株分别转染目的mir的模拟物和阴性对照模拟物,分别以30a-5p组、NC组命名并标记细胞。同时,以未经过处理的Hela细胞作为对照(Control组)。分别用逆转录-聚合酶链反应法检测各组宫颈癌细胞的miR-30a-5p含量。Transwell实验检测3组细胞迁移能力和侵袭能力。Western-blot法检测3组细胞神经-钙粘素(N-cadherin)、α-连环蛋白(α-Catenin)和泛素水解酶22(USP22)表达水平。运用生物信息学方法预测miR-30a-5p的靶基因。采用Western blot法检测USP22过表达对miR-30a-5p抑制EMT的拮抗作用。双荧光素酶实验检测miR-30a-5p与USP22的关系。建立皮下移植瘤模型观察miR-30a-5p的体内作用。【结果】30a-5p组宫颈癌细胞miR-30a-5p的表达水平明显上调,表达水平为Control组的853.82(862.26~843.11)倍(P<0.01)。30a-5p组侵袭细胞数量8.17(8.32~8.03)明显低于Control组(P<0.01)。30a-5p组细胞N-cadherin蛋白的细胞内含量明显下降,α-Catenin蛋白的细胞内含量明显上升,USP22蛋白表达量明显降低。合并USP22过表达处理的30a-5p组宫颈癌细胞中N-cadherin蛋白表达量明显升高,α-Catenin蛋白表达量明显降低。双荧光素酶检验结果显示USP22为miR-30a-5p的下游靶基因(P<0.01)。30a-5p组皮下移植瘤明显小于Control组(P<0.01)。与Control组肿瘤组织相比,30a-5p组肿瘤组织miR-30a-5p的相对含量升高,USP22蛋白含量降低,N-cadherin蛋白的含量降低,α-Catenin蛋白含量升高。【结论】miR-30a-5p在宫颈癌Hela细胞中,可能通过靶向识别下游靶基因USP22,进而抑制其翻译。最终实现对宫颈癌细胞EMT过程的抑制。 相似文献
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MicroRNA-106a-5p (miR-106a-5p) functions as a tumor suppressor in osteosarcoma cells. Here, we aimed to identify novel target genes of miR-106a-5p in osteosarcoma, as well as to investigate their prognostic value and the biological functions. At first, the mammalian runt-related factor 1 (RUNX1) was identified as one of the target genes of miR-106a-5p in osteosarcoma cells by luciferase reporter gene assay, real-time quantitative RT-PCR and Western blot analysis. Then, the expression levels of miR-106a-5p and RUNX1 in osteosarcoma tissues were detected, and their associations with clinicopathological features and patients' prognosis were statistically analyzed. Compared with adjacent non-cancerous tissues, miR-106a-5p and RUNX1 mRNA/protein expression in osteosarcoma tissues were significantly decreased and increased, respectively (all P < 0.01). Low miR-106a-5p, high RUNX1 and miR-106a-5p-low/RUNX1-high expression in osteosarcoma tissues were all significantly associated with advanced Enneking stage, positive metastasis and shorter overall survival (all P < 0.05). Moreover, miR-106a-5p and RUNX1 expression, alone or in combination, were identified as independent prognostic factors for osteosarcoma patients' overall survival. Functionally, the enforced expression of miR-106a-5p significantly suppressed proliferation and invasion of osteosarcoma cells, while the overexpression of RUNX1 effectively reversed its suppressive roles. In conclusion, our findings show the dysregulation of miR-106a-5p-RUNX1 axis in human osteosarcoma tissues and suggest its crucial roles in cancer progression and patients' prognosis. More interestingly, miR-106a-5p may function as a tumor suppressor in osteosarcoma cells via regulating its target gene RUNX1. 相似文献
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9.
Wei-Hua Song Xiao-Jun Feng Shao-Juan Gong Jian-Ming Chen Shou-Mei Wang Dong-Juan Xing Ming-Hua Zhu Shu-Hui Zhang Ai-Min Xu 《Cancer biology & therapy》2015,16(12):1754-1763
microRNAs (miRNAs) are important regulators of tumor development and progression. In this study, we aimed to explore the expression and role of miR-622 in hepatocellular carcinoma (HCC). We found that miR-622 was significantly downregulated in human HCC specimens compared to adjacent noncancerous liver tissues. miR-622 downregulation was significantly associated with aggressive parameters and poor prognosis in HCC. Enforced expression of miR-622 significantly decreased the proliferation and colony formation and induced apoptosis of HCC cells. In vivo studies demonstrated that miR-622 overexpression retarded the growth of HCC xenograft tumors. Bioinformatic analysis and luciferase reporter assays revealed that miR-622 directly targeted the 3′-untranslated region (UTR) of mitogen-activated protein 4 kinase 4 (MAP4K4) mRNA. Ectopic expression of miR-622 led to a significant reduction of MAP4K4 expression in HCC cells and xenograft tumors. Overexpression of MAP4K4 partially restored cell proliferation and colony formation and reversed the induction of apoptosis in miR-622-overexpressing HCC cells. Inhibition of JNK and NF-κB signaling phenocopied the anticancer effects of miR-622 on HCC cells. Taken together, miR-622 acts as a tumor suppressor in HCC and restoration of miR-622 may provide therapeutic benefits in the treatment of HCC. 相似文献
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