Pervasive H3K27 Acetylation Leads to ERV Expression and a Therapeutic Vulnerability in H3K27M Gliomas

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Preventive and Therapeutic Effects of Quercetin on Experimental Radiation Induced Lung Injury in Mice

Objective: To investigate the protective effect of quercetin on radiation induced lung injury (RILI) andrelated mechanisms. Materials and Methods: Mice treated with radiation and/or quercetin were sacrificedat 1-8 weeks after irradiation under anesthesia. Lung tissues were collected for histological examination.Immunohistochemistry (IHC) and Western blotting were performed to detect the protein expression of nuclearfactor-κB (NF-κB) and Mitogen-activated protein kinases (MAPK) pathway. Results: Hematoxylin and eosin (HE)staining showed that radiation controls displayed more severe lung damage than quercetin groups, either highor low dose. Results of IHC and Western blotting demonstrated the expression level of NF-κB to be decreasedand that of an inhibitor of NF-κB (Iκb–α) to be increased by the quercetin intervention compared with theradiation control group. Numbers of JNK/SAPK, p38 and p44/p42 positive inflammatory cells were decreasedin the radiation+quercetin injection group (P<0.05). Conclusions: Quercetin may play a radio-protective rolein mice lung via suppression of NF-κB and MAPK pathways.     

LAMP2抑制肝癌细胞增殖的机制

目的:探索LAMP2分子对肝癌细胞增殖的影响及其机制.方法:首先利用Western blot及QT-PCR技术检测在不同肝癌细胞系中LAMP2分子的表达水平,然后选择一种肝癌细胞系HepG2进行慢病毒转染以建立LAMP2沉默的稳定细胞系HepG2-9455.利用MTT法对比LAMP2沉默细胞系和未沉默细胞系细胞的增殖情况.检测其可能影响的几个关键信号通路分子如PI3K、AKT、NF-κB、ERK等以明确其作用机制.结果:LAMP2在各肝癌细胞系中普遍表达较高,其在正常肝组织中主要分布于胆管周围并且呈极性分布,然而在肝癌组织中LAMP2的定位却发生了紊乱.通过慢病毒构建的稳定细胞系HepG2-9455其LAMP2表达下降了90%,而在下调LAMP2后可以显著抑制肝癌细胞HepG2的增殖.并且在下调LAMP2分子后HepG2细胞的PI3K、AKT和NF-κB分子发生明显下调.结论:LAMP2分子可以通过调节下游的PI3K、NF-κB(p-p65)分子而影响肿瘤细胞的增殖.提示LAMP2分子在肝癌的恶性进展中可能发挥了重要的作用.     

Knockdown of Bcl-3 Inhibits Cell Growth and Induces DNA Damage in HTLV-1-infected Cells)

Oncoprotein Bcl-3 is perceived as an unusual member of IκB family since it can both stimulate and suppressNF-κB activation. Aberrant Bcl-3 results in increased cell proliferation and survival, suggesting a contributionto malignant potential and elevated levels of Bcl-3 have been observed in many HTLV-1-infected T cell lines andATL cells. To investigate the specific roles of Bcl-3 in HTLV-1-infected cells, we knocked down Bcl-3 expressionusing shRNA and then examined the consequences with regard to DNA damage and cell proliferation, as wellas NF-κB activation. The HTLV-1 encoded protein Tax promotes Bcl-3 expression and nuclear translocation.In HTLV-1-infected cells, Bcl-3 knockdown obviously induced DNA damage. Cell growth and NF-κB activationwere reduced in HTLV-1-infected or Tax positive cells when Bcl-3 expression was decreased. Together, our resultsrevealed positive roles of Bcl-3 in DNA stabilization, growth and NF-κB activation in HTLV-1-infected cells.     

The Epidemiology of Myeloproliferative Neoplasms in New Zealand between 2010 and 2017: Insights from the New Zealand Cancer Registry

Background: There is a paucity of data on ethnic disparities in patients with the classical Philadelphia chromosome-negative myeloproliferative neoplasms (MPNs): polycythaemia vera (PV), essential thrombocythaemia (ET) and primary myelofibrosis (PMF). Methods: This study analysed the demographic data for PV, ET and PMF collected by the New Zealand Cancer Registry (NZCR) between 2010 and 2017. Results: We found that the NZCR capture rates were lower than average international incidence rates for PV and ET, but higher for PMF (0.76, 0.99 and 0.82 per 100,000, respectively). PV patients were older and had worse outcomes than expected, which suggests these patients were reported to the registry at an advanced stage of their disease. Polynesian patients with all MPN subtypes, PV, ET and PMF, were younger than their European counterparts both at the time of diagnosis and death (p < 0.001). Male gender was an independent risk factor for mortality from PV and PMF (hazard ratios (HR) of 1.43 and 1.81, respectively; p < 0.05), and Māori ethnicity was an independent risk factor for mortality from PMF (HR: 2.94; p = 0.006). Conclusions: New Zealand Polynesian patients may have increased genetic predisposition to MPN, thus we advocate for modern genetic testing in this ethnic group to identify the cause. Further work is also required to identify modifiable risk factors for mortality in MPN, in particular those associated with male gender and Māori ethnicity; the results may benefit all patients with MPN.     

低氧上调肺腺癌细胞中Annexin A1的表达

背景与目的肿瘤的生长通常会面临缺血缺氧,已有的研究表明膜联蛋白Anx A1(Annexin A1)与肿瘤的关系密切,本研究旨在探讨低氧对肺腺癌细胞Anx A1表达的影响。方法将人肺腺癌细胞A549扩增后,分别在常氧(37oC、5%CO2、21%O2)和低氧(37oC、5%CO2、1%O2)条件下培养4 h、12 h、24 h,随后进行RT-PCR,观察Annexin A1 mRNA水平的变化,Western blot方法观察蛋白表达的变化;测定各组细胞中活性氧(reactive oxygen spe-cies,ROS)的含量,Western blot检测NF-κB核转位;分别以ROS清除剂N-乙酰半胱氨酸(NAC)和NF-κB抑制剂四氢化吡咯二硫代氨基甲酸脂(PDTC)干预后,测定各组细胞中Anx A1蛋白水平的变化。结果 RT-PCR结果显示低氧4h后Anx A1 mRNA水平上升,与常氧组比较有统计学差异(P<0.05),但随后缓慢下降;Western blot结果显示低氧上调A549细胞中Anx A1蛋白的表达,在缺氧4 h时尤为明显;随着细胞缺氧时间的延长,ROS的量也逐渐递增;ROS清除剂NAC和NF-κB抑制剂PDTC明显降低缺氧所致的Anx A1蛋白水平增加。结论低氧上调肺腺癌A549细胞中AnnexinA1 mRNA和蛋白水平的表达,ROS-NF-κB信号通路可能参与这一过程。     

LOX1在胃癌中的表达及其促肿瘤生长的机制探讨

目的:探讨血凝素样氧化型低密度脂蛋白受体1（lectin-like oxidized low density lipoprotein receptor-1,LOX1）在胃癌中的表达及与预后相关性,同时明确其促胃癌生长作用及潜在机制。方法:利用人类癌症基因组图谱(TCGA)、基因表达汇编(GEO)和癌症细胞系百科全书(CCLE)数据库分析LOX1在胃癌组织和细胞中的表达水平;利用多种统计方法分析LOX1表达水平与胃癌患者预后及临床特征的相关性;通过质粒转染敲低LOX1,进一步应用细胞功能实验（CCK-8、克隆形成、EdU实验）探究LOX1对胃癌细胞增殖能力的调控作用;通过Western blot、qPCR、免疫荧光分析LOX1对NF-κB信号通路激活的调控作用。结果:LOX1在胃癌组织和细胞中显著高表达;高水平LOX1提示胃癌患者预后较差且肿瘤较易发生转移;敲低LOX1显著抑制肿瘤细胞增殖;敲低LOX1显著抑制胃癌细胞中NF-κB信号通路的激活。结论:LOX1通过激活NF-κB信号通路对胃癌细胞增殖能力具有调控作用;LOX1可作为生物标记物提示患者预后;靶向LOX1可作为潜在胃癌治疗新方案。     

塞来昔布抑制人类三阴性乳腺癌裸鼠移植瘤生长的实验研究

 【摘要】　目的　探讨塞来昔布（celecoxib）对人类三阴性乳腺癌（TNBC）肿瘤生长及细胞凋亡的影响。方法　32只裸鼠于背部皮下接种人类TNBC细胞株MDA-MB-231,随机分为空白对照组及低、中、高剂量塞来昔布组（25、50、100 mg?kg-1?d-1）。实验结束后,留取移植瘤标本,观察用药前后裸鼠肿瘤体积的变化;流式细胞术（FCM）检测肿瘤细胞凋亡率;免疫组织化学法检测NF-κB p65和p50分子的表达;Western blot法检测凋亡相关分子Caspase-3、Survivin蛋白的表达。结果　塞来昔布治疗组肿瘤体积较对照组均明显减小。中、高剂量塞来昔布治疗组凋亡率分别为（13.58±3.16）％、（21.91±4.75）％,与对照组的（3.15±1.73）％相比差异有统计学意义（t＝6.736,12.151,均P＜0.05）,塞来昔布低、中、高剂量组p65表达阳性率分别为79.3 %、46.7 %、23.9 %,与对照组（89.7 %）相比差异有统计学意义（χ2＝3.312,10.785,15.900,均P＜0.05）。Western blot结果显示,塞来昔布治疗后肿瘤组织中Caspase-3蛋白出现了裂解片段,并且随药物浓度增加,裂解片段表达量逐渐增加。Survivin蛋白随药物浓度增加表达逐渐下调。结论　塞来昔布可以诱导TNBC裸鼠移植瘤细胞凋亡,抑制肿瘤生长,其抗肿瘤作用机制可能部分与抑制p65分子以及下调Survivin蛋白表达有关。     

Effect of Bcl-2 on Apoptosis and Transcription Factor NF-kB Activation Induced by Adriamycin in Bladder Carcinoma BIU87 Cells

Resistance to apoptosis is a major obstacle preventing effective therapy for malignancies. Bcl-2 plays asignificant role in inhibiting apoptosis. We reconstructed a stable human Bcl-2 transfected cell line, BIU87-Bcl-2, that was derived from the transfection of human bladder carcinoma cell line BIU87 with a plasmid vectorcontaining recombinant Bcl-2 [pcDNA3.1(+)-Bcl-2]. A cell line transfected with the plasmid alone [pcDNA3.1(+)-neo] was also established as a control. BIU87 and BIU87-neo proved sensitive to adriamycin induced apoptosis,while BIU87-Bcl-2 was more resistant. In view of the growing evidence that NF-κB may play an important rolein regulating apoptosis, we determined whether Bcl-2 could modulate the activity of NF-κB in bladder carcinomacells. Stimulation of BIU87, BIU87-neo and BIU87-Bcl-2 with ADR resulted in an increase expression of NF-κB(p<0.001). The expression of NF-κB in BIU87-Bcl-2 was higher than in the other two cases, with a concomitantreduction in the IκBκ protein level. These results suggest that the overexpression of Bcl-2 renders human bladdercarcinoma cells resistant to adriamycin -induced cytotoxicity and there is a link between Bcl-2 and the NF-κBsignaling pathway in the suppression of apoptosis.     

干扰素对JAK2 V617F阳性骨髓增殖性肿瘤PD-1/PD-L1及Treg表达的影响

 目的 探讨干扰素-alpha-2b（IFN-α2b）对JAK2 V617F阳性骨髓增殖性肿瘤（MPN）患者中程序性死亡受体-1（PD-1）、程序性死亡配体-1 （PD-L1）及CD4+ CD25+ Foxp3+调节性T细胞（Treg）表达的影响及临床意义。方法 收集JAK2 V617F阳性MPN患者61例，包括初治组41例、IFN-α2b治疗组20例，健康对照组20例。应用荧光定量PCR检测JAK2 V617F/JAK2突变率，流式细胞术检测PD-1、PD-L1、Treg的表达情况。选取15例患者骨髓及外周血标本进行体外细胞培养，应用1×106 U/L IFN-α2b作用48 h后检测PD-1、PD-L1及Treg表达情况。结果 初治组的JAK2 V617F、PD-1、PD-L1及Treg表达明显高于IFN-α2b治疗组及对照组（均P<0.05）。JAK2 V617F突变量≥50%患者骨髓髓系细胞PD-1、PD-L1及外周血Treg细胞均明显高于突变量<50%患者（均P<0.05）。相关性分析结果显示JAK2 V617F突变量与骨髓髓系细胞PD-1、PD-L1和淋巴细胞PD-1呈正相关，与Treg表达无相关性。1×106 U/L IFN-α2b作用48 h后能够体外抑制MPN原代细胞PD-1、PD-L1及Treg的表达（P<0.05）。结论 PD-1、PD-L1及Treg共同参与了MPN的发病过程，干扰素能够不同程度抑制MPNJAK2 V617F、PD-1、PD-L1及Treg表达，进而抑制MPN的进展。     

结直肠癌HPV16型感染与核因子-κB活化的关系研究

 目的　探讨结直肠癌HPV16型感染与核因子 κB(NF κB)活化的关系。方法　应用凝胶电泳迁移率分析 (EMSA)检测 5 0例结直肠癌、30例结直肠腺瘤和 2 0例正常大肠组织核因子NF κBDNA结合活性 ,并用多聚酶链反应 (PCR)和southernblot检测HPV16型DNA。结果　结直肠癌、腺瘤分别与正常结直肠组织比较 ,NF κBDNA结合活性和HPV16型DNA阳性率均明显增高 ,差异有显著性 (P <0 .0 5 ) ;结直肠癌和结直肠腺瘤比较 ,NF κBDNA结合活性和HPV16型DNA阳性率差异均无显著性 (P>0 .0 5 )。HPV16型DNA阳性和阴性结直肠癌患者比较 ,NF κBDNA结合活性差异有显著性 (P <0 .0 5 )。结论　NF KB活化参与HPV16型在结直肠癌的致癌过程     

Targeting EZH2 regulates tumor growth and apoptosis through modulating mitochondria dependent cell-death pathway in HNSCC

EZH2 is a negative prognostic factor and is overexpressed or activated in most human cancers including head and neck squamous cell carcinoma (HNSCC). Analysis of The Cancer Genome Atlas (TCGA) HNSCC data indicated that EZH2 over-expression was associated with high tumor grade and conferred poor prognosis. EZH2 inhibition triggered cell apoptosis, cell cycle arrest and decreased cell growth in vitro. MICU1 (mitochondrial calcium uptake1) was shown to be down regulated when EZH2 expression was inhibited in HNSCC. When the EZH2 and MICU1 were inhibited, HNSCC cells became susceptible to cell cycle arrest and apoptosis. Mitochondrial membrane potential and cytosolic Ca²⁺ concentration analysis suggested that EZH2 and MICU1 were required to maintain mitochondrial membrane potential stability. A xenograft tumor model was used to confirm that EZH2 depletion inhibited HNSCC cell growth and induced tumor cell apoptosis. In summary, EZH2 is a potential anti-tumor target in HNSCC.     

肝癌细胞 miR-183表达及上下游调控机制探讨

目的： miR-183的显著上调已成为临床肝肿瘤发生的普遍特征,但其在肝癌发生中的分子机制亟待阐明。本研究探讨肝癌细胞 Hep3B 中 miR-183的表达及其上游调控机制和下游靶标蛋白变化。方法 MTT 法检测人正常肝细胞株 LO2及人肝癌细胞株 HepG2、Hep3B 的细胞增殖活性。提取细胞的总 RNA 和蛋白,采用 RT-qPCR 和蛋白印迹法分别检测细胞株中 miR-183的表达和细胞外信号调节激酶1／2（extracellular signal-regulated kinase 1／2,ERK1／2）、磷酸化 ERK1／2（phospho-ERK1／2,p-ERK1／2）、磷酸化胞内磷脂酰肌醇激酶（phospho-phosphatidylinositol-3-kinase,p-PI3K）、磷酸化蛋白激酶 B（phospho-protein kinase B,p-AKT）、NF-κB 抑制蛋白α亚基（nuclear factor of kappa light polypeptide gene enhancer in B-cells inhibitor,alpha,IκBα）和程序性细胞死亡因子4（programmed cell death factor 4,PDCD4）的蛋白水平。用抑制剂分别抑制 Hep3B 细胞 ERK、PI3K、AKT 和 NF-κB 信号分子的活性并检测 miR-183的表达水平及 PD-CD4蛋白表达水平。结果 LO2、HepG2和 Hep3B 细胞在48 h 的增殖倍数分别为8．76±0．22、16．61±1．59和19．86±0．69,F ＝159．90,P ＜0．001。与 LO2（41．68±9．62）和 HepG2（41．53±1．20）细胞相比,Hep3B（69．15±11．02）的 miR-183细胞表达水平显著升高,F ＝10．250,P ＝0．012。与 LO2相比,Hep3B 细胞的 p-ERK1、ERK1、p-AKT 和 IκBα的蛋白水平明显升高,分别为 LO2的10．87、24．68、6．67和1．92倍;PDCD4的蛋白水平明显下降,为 LO2的0．14倍。与LO2细胞相比,HepG2细胞的 IκBα和 PDCD4蛋白表达明显升高,分别为 LO2的4．46和7．90倍。抑制 ERK 的活性后24 h,miR-183表达水平显著上升,F ＝215．459,P ＜0．001;抑制 Hep3B 细胞的 PI3K 活性后12和24 h,miR-183表达水平显著降低,F ＝80．215,P ＜0．001;抑制 AKT 的活性后12和24 h,miR-183表达水平显著下降,F ＝101．947,P ＜0．001;抑制 NF-κB 的活性后12和24 h,miR-183表达水平没有显著变化,F ＝1．826,P ＝0．216。抑制 ERK 和 NF-κB 信号分子活性对 PDCD4的蛋白表达没有显著影响。抑制 PI3K 和 AKT 信号分子活性可明显提升 PDCD4的蛋白表达水平。结论在 Hep3B 细胞中,PI3K／AKT 对 miR-183的表达有显著的促进作用,而 ERK 对 miR-183的表达有显著的抑制作用,NF-κB 不是调控 miR-183表达的主要信号分子。PDCD4是 miR-183的重要下游靶蛋白。     

茶多酚对小鼠Lewis肺癌移植瘤中NF-κB、COX-2、Survivin表达的影响

背景与目的 肺癌是全球第一大恶性肿瘤,前期研究表明茶多酚具有一定的抗肺癌新生血管生成作用,本研究旨在观察茶多酚对小鼠Lewis肺癌移植瘤中NF-κB、COX-2、Survivin表达的影响,进而探讨茶多酚抗新生血管生成的效应机制.方法 建立C57BL/6小鼠肺癌移植瘤模型,测定模型对照组、沙利度胺组、茶多酚组以及茶多酚联合沙利度胺组的肿瘤抑制率,并且采用免疫组化法检测各组NF-κB、COX-2、Survivin表达水平,以探讨其抗肿瘤的分子机制.结果 实验表明,茶多酚具有如下作用:①沙利度胺组、茶多酚组以及茶多酚联合沙利度胺组的肿瘤抑制率分别为17.26％、20.81％和44.32％,茶多酚联合沙利度胺组与模型组瘤重比较,差异具有统计学意义(P＜0.05)；②NF-κB表达在茶多酚组及联合用药组有所降低,与模型对照组相比.联合用药组NF-κB表达明显下降,差异具有统计学意义( P＜0.05)；③COX-2表达在各治疗组均有所下降,与模型对照组相比,联合用药组表达明显下降(P＜0.05)；④Survivin表达在各治疗组均较模型对照组明显降低(p＜0.05),其中茶多酚组下降最为明显(P＜0.01).结论 茶多酚联合沙利度胺组对肺癌有明显抑制作用,其机制可能与抑制NF-κB信号通路的异常激活、抑制NF-κB活化、降低COX-2表达、并降低内皮细胞Survivin表达从而抗肺癌新生血管生成相关.     

miR-449a Suppresses Tumor Growth,Migration, and Invasion in Non-Small Cell Lung Cancer by Targeting a HMGB1-Mediated NF-kB Signaling Pathway

MicroRNAs (miRNAs) have been reported to be involved in many human cancers and tumor progression. The dysregulation of miR-449a is found in many types of malignancies and is associated with tumor growth, migration, and invasion. However, its expression and function in non-small cell lung cancer (NSCLC) still remains unclear. In our study, miR-449a was found to be downregulated in both NSCLC tissues and cell lines, and low miR-449a expression was obviously associated with tumor differentiation, TMN stage, and poor overall survival (OS). Moreover, we demonstrated that miR-449a could inhibit tumor proliferation, migration, and invasion in NSCLC. We also confirmed that HMGB1 was a direct target gene of miR-449a in NSCLC with dual-luciferase reporter assay, and upregulation of HMGB1 could reverse the miR-449a-induced suppression of growth, migration, and invasion in NSCLC cells. Last, we found that miR-449a suppressed tumor initiation and development through the NF- B signaling pathway. These results indicate that miR-449a functions as a tumor suppressor in NSCLC by targeting the HMGB1-mediated NF- B signaling pathway in NSCLC.     

骨肉瘤细胞和组织H3K27me3表达与临床病理特征相关性研究

目的 组蛋白H3K27三甲基化(H3K27me3)在肿瘤发生发展过程中起着重要作用,研究发现H3K27me3在肝癌和前列腺癌等恶性肿瘤中的表达和临床病理特征存在相关性,但其在骨肉瘤中的研究相对较少.本研究分析H3K27me3在骨肉瘤细胞和组织中的表达及其与临床病理的关系,并探讨H3K27me3在骨肉瘤发生和发展中的作用和意义.方法 所有切片均来自于河北医科大学第四医院骨科2005-01-01-2011 01-01手术切除的标本.采用蛋白印迹法检测骨肉瘤MG-63、U2-OS、Sa-OS细胞系及hFOB1.19成骨细胞中H3K27me3表达的水平差异;采用免疫组织化学染色方法检测53例骨肉瘤组织及16例骨软骨瘤组织中H3K27me3的表达水平.KaplawMeier分析比较H3K27me3高表达和低表达患者生存率之间的差异.并应用Cox回归模型分析其表达水平对预后影响.结果 hFOB1.19、MG-63、U2-OS和Sa-OS中H3K27me3蛋白表达水平分别为0.37±0.06、0.86±0.06、0.79±0.07和0.83±0.05,与hFOB1.19细胞中H3K27me3表达相比,3组骨肉瘤细胞系中H3K27me3蛋白表达水平均显著升高,P=0.023;与骨软骨瘤组织相比(56.3％),H3K27me3在骨肉瘤组织中高表达(84.9％),二者差异有统计学意义(P＜0.001),并与肿瘤大小、肺转移、Enneking分期和生存率有关,P值分别为0.037、0.020、0.023和0.046.且其表达水平与患者生存期显著相关,P=0.012.结论 H3K27me3在骨肉瘤细胞及骨肉瘤组织中呈高表达,并与肿瘤的临床病理特征相关,可能会是骨肉瘤患者重要的预后因子及治疗靶点.