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941.
942.
Kai Yang Jie Shen Fu-Qing Tan Xiang-Yi Zheng Li-Ping Xie 《International journal of medical sciences》2021,18(13):3039
Small double-stranded RNAs (dsRNAs) have been proved to effectively up-regulate the expression of particular genes by targeting their promoters. These small dsRNAs were also termed small activating RNAs (saRNAs). We previously reported that several small double-stranded RNAs (dsRNAs) targeting the PRKC apoptosis WT1 regulator (PAWR) promoter can up-regulate PAWR gene expression effectively in human cancer cells. The present study was conducted to evaluate the antitumor potential of PAWR gene induction by these saRNAs in bladder cancer. Promisingly, we found that up-regulation of PAWR by saRNA inhibited the growth of bladder cancer cells by inducing cell apoptosis and cell cycle arrest which was related to inhibition of anti‑apoptotic protein Bcl-2 and inactivation of the NF-κB and Akt pathways. The activation of the caspase cascade and the regulation of cell cycle related proteins also supported the efficacy of the treatment. Moreover, our study also showed that these saRNAs cooperated with cisplatin in the inhibition of bladder cancer cells. Overall, these data suggest that activation of PAWR by saRNA may have a therapeutic benefit for bladder cancer. 相似文献
943.
Kai-Fu Chang Jinghua Tsai Chang Xiao-Fan Huang Ya-Chih Huang Chia-Yu Li Jun-Cheng Weng Chih-Yen Hsiao Hui-Ju Hsu Nu-Man Tsai 《International journal of medical sciences》2021,18(11):2417
Glioblastoma (GBM) is the most common malignant primary brain tumor in humans, exhibiting highly infiltrative growth and drug resistance to conventional chemotherapy. Cedrus atlantica (CAt) extract has been shown to decrease postoperative pain and inhibit the growth of K562 leukemia cells. The aim of this study was to assess the anti-GBM activity and molecular mechanism of CAt extract in vitro and in vivo. The results showed that CAt extract greatly suppressed GBM cells both in vitro and in vivo and enhanced the survival rate in subcutaneous and orthotopic animal models. Moreover, CAt extract increased the level of ROS and induced DNA damage, resulting in cell cycle arrest at the G0/G1 phase and cell apoptosis. Western blotting results indicated that CAt extract regulates p53/p21 and CDK4/cyclin D1 protein expression and activates extrinsic and intrinsic apoptosis. Furthermore, CAt extract enhanced the cytotoxicity of Temozolomide and decreased AKT/mTOR signaling by combination treatment. In toxicity assays, CAt extract exhibited low cytotoxicity toward normal cells or organs in vitro and in vivo. CAt extract suppresses the growth of GBM by induction of genotoxicity and activation of apoptosis. The results of this study suggest that CAt extract can be developed as a therapeutic agent or adjuvant for GBM treatment in the future. 相似文献
944.
目的 探讨芳香新塔花总黄酮(Ziziphora clinopodioides flavonoids,ZCF)通过调控miR-874-3p表达影响过氧化氢(H2O2)诱导的神经细胞氧化损伤和凋亡.方法 采用流式细胞术检测不同浓度ZCF对H2O2诱导的SK-N-SH细胞凋亡的影响.试剂盒检测LDH、MDA和SOD水平.实时定量PCR分析miR-874-3p表达量.转染miR-874-3p模拟物至SK-N-SH细胞,采用以上方法分析miR-874-3p过表达对H2O2诱导的SK-N-SH细胞氧化损伤和凋亡的影响.结果 H2O2诱导后SK-N-SH细胞凋亡率、LDH释放率、MDA水平显著升高,SOD活性、miR-874-3p表达量显著降低(P<0.05).ZCF显著抑制H2O2诱导的SK-N-SH细胞凋亡、LDH释放,降低MDA水平,增加SOD活性以及miR-874-3p表达量(P<0.05).过表达miR-874-3p显著抑制H2O2诱导的SK-N-SH细胞凋亡、LDH释放,降低MDA水平,增加SOD活性(P<0.05).抑制miR-874-3p显著减弱ZCF对H2O2诱导的SK-N-SH细胞氧化损伤和凋亡的影响(P<0.05).结论 ZCF通过上调miR-874-3p表达可减轻H2O2诱导的神经细胞氧化损伤和凋亡. 相似文献
945.
Agnieszka Pluta Tadeusz Robak Barbara Cebula Agata Majchrzak Piotr Pluta Kamil Brzozowski Konrad Stpka Anna Szmigielska-Kapon Olga Grzybowska-Izydorczyk Magdalena Czemerska Piotr Smolewski Agnieszka Wierzbowska 《Archives of Medical Science》2021,17(3):700
IntroductionThe misbalance between a family of inhibitor of apoptosis proteins (IAP), regulated by the nuclear factor kappa B (NF-κB) and their natural antagonist second mitochondrial-derived activator of caspases/direct IAP binding protein with low pI (Smac/DIABLO) are important to biology of acute myeloid leukemia (AML).Material and methodsThe aim of the study was to assess NF-κB and Smac/DIABLO proteins expression in blasts of 109 newly diagnosed AML patients using the multicolor flow cytometry and evaluate their influence on AML patients outcome.ResultsExpression of NF-κB and of Smac/DIABLO proteins were found in 95% and 98% of the patients, respectively. A negative correlation between Smac/DIABLO and NF-κB was observed. Age < 60 years old as well as higher Smac/DIABLO expression were associated with a higher probability of complete response achievement in the multivariate analysis. Longer overall survival (OS) in the univariate and multivariate analyses was influenced by age < 60 years old, a favorable or intermediate-risk karyotype and high Smac/DIABLO expression. Additionally, in the survival analysis of the subgroups, the patients aged < 60 years old, with high Smac/DIABLO expression, lower NF-κB expression and < 50% of bone marrow blasts who were treated with standard treatment had better OS.ConclusionsLower NF-κB and higher Smac/DIABLO expression may influence AML patients outcome. 相似文献
946.
947.
目的探讨Cpne5蛋白在SH-SY5Y细胞凋亡中表达量的变化。方法显微镜观察细胞形态及流式细胞术检测凋亡率,鉴定A23187诱导SH-SY5Y细胞凋亡及血清剥夺诱导凋亡的模型;免疫印迹法检测两种凋亡过程中Cpne5蛋白表达量的变化。结果 10μmol/L A23187诱导SH-SY5Y细胞24h,细胞出现皱缩、凋亡率增加。A23187诱导0.5h,Cpne5蛋白表达量即出现明显的上升,持续至12h;在24h时Cpne5蛋白表达量回落至诱导前水平。血清剥夺72h的SH-SY5Y细胞24份,凋亡率为23.2±2.1%,与对照组1.1±0.1%比,差异有统计学意义(P〈0.01)。免疫印迹结果表明,SH-SY5Y细胞分别经血清剥夺1h、6h、12h、24h、72h对Cpne5蛋白表达量无明显变化。结论 A23187诱导SH-SY5Y细胞凋亡早期Cpne5蛋白表达量有显著变化;提示Cpne5基因可能参与凋亡调控的钙信号通路。 相似文献
948.
目的检测子痫前期患者胎盘组织中TGF—β1/Smad的表达,探求TGF—β1/Smad信号转导通路在子痫前期发病中的作用。方法采用免疫组织化学法检测40例子痫前期(轻、重度)和正常孕妇15例正常妊娠妇女胎盘中TGF-β1以及Smad3、Smad4、Smad7的分布和表达,采用TUNEL法检测三组胎盘滋养细胞凋亡的情况。结果TGF-β以及Smad2、Smad3、Smad4、Smad7在正常妊娠和子痫前期患者胎盘的滋养细胞、内皮细胞、基质细胞中均有表达,以滋养细胞表达为主。TGF-β1以及Smad3、Smad4在正常妊娠组、子痫前期轻度组和重度组的表达强度及范围均呈逐渐升高趋势,Smad7在正常妊娠组、子痫前期轻度和重度组表达强度及范围依次呈逐渐下降趋势。正常妊娠和子痫前期患者胎盘的滋养细胞、内皮细胞、基质细胞均存在凋亡,以滋养细胞凋亡为主。重度子痫前期组胎盘滋养细胞凋亡(1.02)%显著高于子痫前期轻度组(0.73)%,子痫前期轻度组显著高于正常妊娠组(0.38)%,P〈0.05。滋养细胞TGF—β1的表达与滋养细胞凋亡具有相关性(r=0.96,P〈0.05)。结论子痫前期患者胎盘组织中的TGF—β1可能是通过Smad信号转导蛋白抑制滋养细胞浸润,诱导细胞凋亡。 相似文献
949.
目的 观察zeste基因增强子同源物2(EZH2)抑制剂GSK126对人舌鳞状细胞癌细胞体外增殖与凋亡的影响,并探讨其相关机制,为舌鳞状细胞癌的临床治疗提供新思路。方法 将不同浓度的GSK126作用于舌鳞状细胞癌CAL-27细胞,通过甲基噻唑基四唑(MTT)、克隆形成、5-乙炔基-2’脱氧尿嘧啶核苷(EdU)荧光染色实验检测药物对细胞增殖能力的影响;采用Hoechst33342荧光染色、JC-1法观察细胞凋亡情况;采用Western blot法检测CAL-27细胞内相关蛋白细胞外调节蛋白激酶(ERK)、磷酸化的细胞外调节蛋白激酶(p-ERK)、Bax、Bcl-2、Cleaved caspase-9的表达水平。结果 GSK126能抑制CAL-27细胞增殖并对细胞凋亡有促进作用。GSK126能下调细胞内p-ERK、Bcl-2的表达水平,同时可增加Bax、Cleaved caspase-9的表达(P<0.05)。结论 GSK126可抑制舌鳞状细胞癌CAL-27细胞的增殖,并且能促进其凋亡,其机制可能与抑制MEK/ERK信号通路以及激活Bax/Bcl-2通路有关。 相似文献
950.
Etsuko Oshima Takeshi Ishihara Osamu Yokota Hanae Nakashima‐Yasuda Shigeto Nagao Chikako Ikeda Jun Naohara Seishi Terada Yosuke Uchitomi 《Brain pathology (Zurich, Switzerland)》2013,23(6):633-644
To clarify whether long‐term oral ingestion of aluminum (Al) can increase tau aggregation in mammals, we examined the effects of oral Al administration on tau accumulation, apoptosis in the central nervous system (CNS) and motor function using tau transgenic (Tg) mice that show very slowly progressive tau accumulation. Al‐treated tau Tg mice had almost twice as many tau‐positive inclusions in the spinal cord as tau Tg mice without Al treatment at 12 months of age, a difference that reached statistical significance, and the development of pretangle‐like tau aggregates in the brain was also significantly advanced from 9 months. Al exposure did not induce any tau pathology in wild‐type (WT) mice. Apoptosis was observed in the hippocampus in Al‐treated tau Tg mice, but was virtually absent in the other experimental groups. Motor function as assessed by the tail suspension test was most severely impaired in Al‐treated tau Tg mice. Given our results, chronic oral ingestion of Al may more strongly promote tau aggregation, apoptosis and neurological dysfunction if individuals already had a pathological process causing tau aggregation. These findings may also implicate chronic Al neurotoxicity in humans, who frequently have had mild tau pathology from a young age. 相似文献