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101.
目的探讨麦冬皂苷B对人黑色素瘤(Melanoma)A375细胞增殖,凋亡和细胞周期的影响以及相关机制。方法麦冬皂苷B处理A375细胞后,采用CCK-8法检测细胞活力;流式细胞仪检测A375细胞周期变化及细胞凋亡水平;Hoechst33258荧光染色法观察细胞凋亡形态;免疫印迹法检测麦冬皂苷B对A375细胞PI3K,p-PI3K,AKT,p-AKT蛋白以及通路下游凋亡相关蛋白Bcl-2,Bax,Cleaved-caspase3表达的影响。结果麦冬皂苷B能抑制A375细胞增殖活力及PI3K/Akt/mTOR通路的活化;麦冬皂苷B促进了A375细胞内Bax和Cleaved-caspase 3的表达,抑制Bcl-2表达,诱导人黑色素瘤细胞发生凋亡;麦冬皂苷B阻滞了A375细胞细胞周期,G0/G1期细胞比例明显升高;PI3K/Akt/mTOR通路活化剂IGF-1处理A375细胞后抑制了麦冬皂苷B的上述作用。结论麦冬皂苷B能抑制A375细胞的增殖,诱导细胞发生凋亡,阻滞细胞周期于G0/G1期。  相似文献   
102.
BackgroundUncontrol cell growth and proliferation is acknowledged to responsible for cancer-related deaths by disorganizing the balance of growth promotion and growth limitation. Aberrant expression of microRNA play essential roles in cancer development, leads to cell proliferation, growth and survival, and promotes the development of various human tumors, including osteosarcoma. Elucidating the molecular mechanism of this abnormality in osteosarcoma carcinogenesis may improve diagnostic and therapeutic strategies for this malignancy.MethodsThe expression of miR-664 in osteosarcoma cell lines and osteosarcoma tissues was examined using real-time PCR. The effects of miR-664 on osteosarcoma cell proliferation were evaluated by 3-(4,5-Dimethyl-2-thiazolyl)-2,5-diphenyl-2H-tetrazolium bromide (MTT) assay, colony formation and Anchorage-independent growth ability assay. The effect of miR-664 on FOXO4 was determine by luciferase assays and western blot assay.ResultsThe expression of miR-664 was markedly upregulated in osteosarcoma cell lines and tissues, and upregulation of miR-664 enhanced, whereas downregulation of miR-664 inhibited the proliferation of osteosarcoma cells in vivo. Furthermore, using bioinformatics and biological approaches, we showed that miR-664 directly targeted and suppressed the expression of tumor suppressors FOXO4.ConclusionsOur findings suggest that miR-664 functions as an oncogene miRNA and has an important role in promoting human osteosarcoma cell proliferation by suppressing FOXO4 expression. These data suggests that miR-664 may represent a novel therapeutic target of microRNA-mediated suppression of cell proliferation in osteosarcoma.  相似文献   
103.
Long non-coding RNAs (lncRNAs) have been identified as crucial regulators in the tumorigenesis and progression of hepatocellular carcinoma (HCC). Recently, long intergenic non-protein coding RNA 205 (LINC00205) has been identified as a prognostic biomarker in HCC. However, the biological role of LINC0205 and its potential molecular mechanism are poorly investigated. Here, we found that the expression of LINC00205 was dramatically up-regulated in HCC tissues compared to adjacent nontumor tissues. Furthermore, the level of LINC00205 in both Hep3B and Huh7 cells was prominently higher than that in normal hepatic cell line LO2. Notably, the high expression of LINC00205 was strongly correlated with tumor size ≥5 cm, venous infiltration and advanced tumor stages. Functionally, LINC00205 knockdown obviously repressed the proliferation, migration and invasion of Hep3B and Huh7 cells in vitro. An inverse correlation between LINC00205 and miR-122-5p was detected in HCC tissues. Interestingly, LINC00205 knockdown increased the level of miR-122-5p in both Hep3B and Huh7 cells. Mechanistically, luciferase reporter assay demonstrated LINC00205 acted as a competing endogenous RNA (ceRNA) by directly interacting with miR-122-5p. More importantly, miR-122-5p overexpression significantly restrained the proliferation, migration and invasion of HCC cells. Collectively, our study provides solid evidence to support the oncogenic role of LINC00205 in HCC, which may be benefit for the improvement of HCC therapy.  相似文献   
104.

Objective

MicroRNA-93 (miR-93) is upregulated in the urine of patients with bladder cancer (BC). Here, we investigated the role of miR-93 in BC progression and explored the underlying mechanism.

Methods

miR-93 expression in BC tissues and cells was detected by real time-polymerase chain reaction. The effects of miR-93 and pigment epithelium-derived factor (PEDF) on cell proliferation and invasion were assessed using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide and Transwell assays. The binding of miR-93 to the 3′-untranslated region of PEDF was identified by the luciferase reporter assay.

Results

miR-93 expression was higher in BC tissues than in normal controls, and its expression was associated with tumor stage and node stage. Inhibition of miR-93 suppressed the proliferation and invasion of BC cells. PEDF was identified as a target of miR-93 and shown to mediate the effect of miR-93 on cell proliferation and invasion.

Conclusions

The present data suggested that miR-93 promoted BC cell proliferation and invasion by targeting PEDF, providing new biomarkers and targets for BC diagnosis and treatment.  相似文献   
105.
 目的 探讨异黏蛋白(Metadherin, MTDH)对鼻咽癌细胞增殖及紫杉醇耐药的影响。方法 采用慢病毒介导的MTDH cDNA和MTDH-shRNA转染鼻咽癌细胞,分别上调和抑制MTDH的表达。CCK-8法、流式细胞实验分别检测细胞增殖能力、细胞周期及凋亡改变。CCK-8法确定紫杉醇对鼻咽癌细胞的IC30、IC50、IIC70,并检测IC30、IC50、IC70浓度下MTDH过表达组与沉默组细胞生存率改变。结果 MTDH上调后5-8F、HNE-1细胞的增殖能力均增强,而沉默MTDH后细胞的增殖能力均降低。MTDH沉默组的G1期细胞比例明显增加。MTDH过表达组细胞凋亡率降低,MTDH沉默组细胞凋亡率增加。MTDH表达上调之后,鼻咽癌细胞对紫杉醇的敏感度降低,在IC70、IC50浓度下,MTDH过表达组细胞的生存率高于对照组细胞。沉默MTDH之后,鼻咽癌细胞对紫杉醇的敏感度升高,在IC50、IC30浓度下,MTDH沉默组细胞的生存率低于对照组细胞。结论 MTDH在促进鼻咽癌细胞增殖中起重要作用,其高表达可促进鼻咽癌细胞紫杉醇耐药性的产生。  相似文献   
106.
目的 探讨微小RNA-148a-3p(miR-148a-3p)对丝裂原活化蛋白激酶激酶激酶9(MAP3K9)的靶向调控作用及对胃癌细胞增殖和凋亡的影响。方法 向对数生长期胃癌细胞株MGC-803转染miR-148a-3p模拟物(mimics组)和阴性对照(NC组),以未转染的MGC-803细胞为对照组;采用实时定量PCR(QPCR)检测各组miR-148a-3p水平以评价转染效率,MTT法检测各组细胞增殖能力,流式细胞术检测各组细胞凋亡情况,分别采用QPCR和Western blotting检测Bcl-2、Bax、caspase-3及MAP3K9 mRNA和蛋白水平,同时采用双荧光素酶报告实验验证miR-148a-3p与MAP3K9的靶向作用关系。结果 QPCR结果显示,对照组、NC组和mimics组的miR-148a-3p水平分别为1.021±0.123、1.087±0.196和2.854±0.368,与对照组和NC组比较,mimics组的miR-148a-3p水平升高(P<0.05)。mimics组MGC-803细胞的增殖活力较其余两组减弱(P<0.05)。mimics组MGC-803细胞凋亡率为(15.2±1.6)%,高于对照组的(3.5±0.9%)%和NC组的(4.5±1.1)%,差异具有统计学意义(P<0.05)。与对照组和NC组比较,mimics组的MAP3K9和Bcl-2的mRNA和蛋白水平均下调,而Bax和caspase-3的mRNA和蛋白水平均上调(P<0.05);双荧光素酶报告实验证实MAP3K9是miR-148a-3p的直接作用靶点。结论 MiR-148a-3p可抑制胃癌细胞MGC-803的增殖并诱导其凋亡,可能通过靶向MAP3K9来发挥抑癌作用,调控miR-148a-3p/MAP3K9轴在胃癌防治中有一定应用前景。  相似文献   
107.
Aberrant proliferation and migration of retinal pigment epithelium (RPE) cells contributes to the pathology of various ocular diseases. miR-27b has been reported to be crucial in the regulation of cell differentiation, proliferation, apoptosis, and migration. However, the role of miR-27b on RPE proliferation and migration remains largely unknown. Here the effect of miR-27b on ARPE-19 cells under platelet-derived growth factor (PDGF)-BB stimulation was explored. In this study, we found that the expression level of miR-27b was significantly reduced in ARPE-19 cells under PDGF-BB stimulation. Ectopic expression of miR-27b remarkably inhibited PDGF-BB-induced proliferation and migration in ARPE-19 cells. Furthermore, bioinformatic analysis and luciferase reporter assay showed that NADPH oxidase 2 (Nox2) was a direct target for miR-27b, and that knockdown of Nox2 expression mimicked the inhibitory effect of miR-27b on PDGF-BB ?induced proliferation and migration in ARPE-19 cells, whereas, restoration of Nox2 expression showed an opposite effect. In addition, the ROS production and the activation of P13K/AKT/mTOR signaling induced by PDGF-BB were also suppressed by miR-27b overexpression or Nox2 silencing. Thus, these findings indicated that miR-27b exerted its protective role in RPE cells under PDGF-BB stimulation was partially through regulation of Nox2 and its downstream P13K/AKT/mTOR signaling, which might be a potential therapeutic approach for treatment of diseases caused by RPE proliferation, and migration.  相似文献   
108.
NIMA Related Kinase 6 (Nek6) is a protein kinase involved in various cellular processes, including cell cycle regulation, apopotosis, senescence, telomere maintainance and chemoresistance. In the present study, we investigated the role of Nek6 in breast tumorigenesis and the prognostic merit of Nek6 expression in breast cancer. Immunohistochemistry and Western blot analyses was conducted to determine the expression profile of Nek6 in 133 breast cancer specimens. Nek6 was overexpressed in a majority of breast cancer specimens, compared with the adjacent non-tumorous tissues. Furthermore, we revealed that high expression of Nek6 was associated with histologic grade, tumor size and TNM stage in breast cancer. Liner regression analysis showed a significant association between the levels of Nek6 and Ki-67. Cox regression analysis indicated that Nek6 expression was an independent prognostic predictor for breast cancer. Moreover, intracellular level of Nek6 was remarkably increased following the release from serum starvation in MCF-7 cells. EdU incorporation assay indicated that depletion of Nek6 remarkably impaired the proliferation of MCF-7 cells. Finally, spheroid formation assay revealed that interference of Nek6 led to diminished oncospheroid-forming capacity of breast cancer cells. In conclusion, our results imply that Nek6 plays a facilitating role in breast cancer cell proliferation and may serve as a promising therapeutic target for breast cancer.  相似文献   
109.
目的: 研究细胞外基质聚二甲基硅氧烷(polydimethylsiloxane,PDMS)硬度对牙髓干细胞(DPSCs)增殖和成骨分化的影响及其机制。方法: 收集南京医科大学附属常州市第二人民医院因正畸而拔除的前磨牙作为实验材料,分离、培养DPSCs,制作PDMS基质。根据不同硬度,将PDMS基质分为A组(基料/固化剂=10∶1,硬度135 kPa)、B组(基料/固化剂= 20∶1,硬度54 kPa)和C组(基料/固化剂= 30∶1,硬度16 kPa),另设不含PDMS基质的对照组,在各组基质上培养DPSCs细胞,采用CCK-8法检测各组DPSCs细胞培养至1、3、5、7天时的增殖率,采用茜素红染色鉴定各组DPSCs细胞成骨效果,采用蛋白免疫印迹法(Western blot)检测各组DPSCs细胞中骨钙素(OCN)、RUNX2、细胞外因子1(Wnt1)、β连环素(β-catenin)蛋白表达量。采用SPSS 22.0软件包对数据进行统计学分析。结果: 茜素红染色结果显示,A组DPSCs细胞形态发生明显变化,排列具有明显方向性,由多角形、梭形逐渐变为方形,出现钙化小结节,B组钙化小结节明显少于A组,C组钙化小结节明显少于B组,对照组钙化小结节极少。B组DPSCs细胞各时刻增殖率及OCN、RUNX2、Wnt1、β-catenin蛋白表达量均显著低于A组(P<0.05),C组DPSCs细胞各时刻增殖率及OCN、RUNX2、Wnt1、β-catenin蛋白表达量显著低于B组(P<0.05),对照组DPSCs细胞各时刻增殖率及OCN、RUNX2、Wnt1、β-catenin蛋白表达量显著低于C组(P<0.05)。结论: 较硬细胞外基质可能通过激活Wnt/β-catenin信号通路,促进牙髓干细胞增殖和成骨分化,这可为牙周组织工程新材料的研发提供理论基础。  相似文献   
110.
目的 探讨S100钙离子结合蛋白A6(S100A6)对食管腺癌SK-GT-4细胞增殖和迁移的影响。 方法 慢病毒转染,构建稳定细胞系shNC和shS100A6,Real-time PCR检测S100A6 mRNA表达情况;倒置显微镜和MTT检测细胞的增殖能力,Transwell检测细胞的迁移能力及U0126(MER1/2的抑制剂)、LY294002(PI3K抑制剂)对细胞增殖、迁移的影响;Western blotting检测细胞中S100A6、p-ERK、p-Akt及其下游参与增殖、迁移的相关蛋白的表达情况,检测U0126、LY294002对p-ERK、p-Akt及其下游参与增殖、迁移的相关蛋白表达的影响。 结果 构建了敲低S100A6的稳定细胞系,敲低S100A6促进了细胞的增殖和迁移,p-ERK、p-Akt水平升高,细胞周期抑制蛋白p21表达量下降、细胞周期蛋白D1(cyclinD1)表达升高,间质细胞标志蛋白——波形蛋白(vimentin)、β-连环蛋白(β-catenin)表达升高;U0126处理shS100A6细胞后,对细胞的增殖无影响,抑制细胞的迁移,p-ERK、β-catenin表达下降;LY294002处理shS100A6细胞后,抑制细胞的增殖和迁移,p-Akt表达下降,p21表达量升高,cyclinD1表达量下降,β-catenin表达下降。 结论 低表达S100A6促进细胞的增殖和迁移,其可能机制是通过p-Akt调控细胞周期的进程促进细胞增殖,通过激活p-Akt/p-ERK调控β-catenin促进细胞的迁移。  相似文献   
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