姜黄素对人胃腺癌细胞株BGC-823生长抑制及诱导凋亡的作用

目的 探讨姜黄素对人胃腺癌细胞BGC-823的生长抑制及诱导凋亡作用。方法MTT法检测不同浓度姜黄素对人胃腺癌BGC-823细胞的生长抑制作用,计算半数抑制浓度（IC₅₀）;将1.2μmol／L姜黄素作用于BGC-823细胞24、48、72h,用DAPI染色检测细胞凋亡;用RT-PCR、Western blotting法分别检测姜黄素对Bax、Bcl-2基因以及Bax、Bcl-2、caspase-3蛋白的影响。结果 不同浓度的姜黄素作用于BGC-823细胞0～72h后,细胞呈不同程度的抑制作用,随着药物浓度的增加,抑制率明显上升,作用48h的IC₅₀为1.2μmol／L。DAPI染色可见典型的凋亡细胞形态学特征。RT-PCR、Western blotting结果显示1.2μmol/L姜黄素可以增加Bax表达、减少Bcl-2表达和激活caspase-3。结论 姜黄素对人胃腺癌BGC-823细胞有生长抑制和诱导凋亡的作用,这可能与增加Bax表达、减少Bcl-2表达、激活caspase-3有关。     

舒林酸对胃癌细胞生长抑制作用的体外观察

背景与目的:体外研究舒林酸对人胃癌BGC-823细胞的生长抑制作用,探讨其作用机制。材料与方法:将舒林酸作用于人胃癌BGC-823细胞,并设置不同的作用浓度和作用时间。以体外药物敏感实验(单核细胞直接细胞毒测定Mono-nuclearcelldireccytotoxicityassay,MTT)检测舒林酸在不同浓度及不同作用时间下对人胃癌BGC-823细胞的增殖抑制效应;流式细胞仪检测胃癌细胞周期分布;透射电镜观察药物作用后细胞凋亡的形态学改变;免疫组化检测细胞增殖(ki-67)、凋亡抑制基因(bcl-2)及还氧合酶(COX-2)蛋白的表达。结果:舒林酸对人胃癌BGC-823细胞有生长抑制作用,使G0/G1期比例增高,S期比例降低;透射电镜观察到细胞凋亡的形态特征及凋亡小体,而ki-67、bcl-2及COX-2蛋白表达阳性率显著降低;上述作用均呈时间和剂量依赖性。结论:舒林酸在体外具有良好的抑制胃癌BGC-823细胞生长的作用,其机制涉及影响细胞周期分布、诱导细胞凋亡及抑制COX-2、ki-67及bcl-2蛋白的表达。     

Lg-1诱导人胃癌细胞系BGC-823凋亡作用及机制的探讨

目的:研究新鬼臼毒素衍生物4β-4-脱氧-氮取代的异亮氨酸(5-FU基)-戊醇酯-4’-去甲表鬼臼(Lg-1)对人胃癌细胞系BGC-823的诱导凋亡作用及机制.方法:噻唑蓝(MTT)、流式细胞术和Hoechs33258染色分别检测Lg-1对BGC-823细胞增殖、细胞周期及凋亡的影响.荧光定量RT-PCR(qRT-PCR)检测药物处理后对BGC-823细胞凋亡相关基因p53、Bax、Bcl-2、p21和Caspase-3表达的影响.结果:Lg-1对BGC-823细胞增殖具有明显剂量和时间依赖的抑制作用,随药物浓度增加,抑制效应增强,药物浓度为0.01、0.1、1和10 μmol/L时,Lg-1对BGC-823的抑制率分别为23.5％、30.8％、32.4％和52.1％,与依托泊苷(Vp-16)处理组(3.5％、8.7％、10.9％和21.3％)比较差异有统计学意义,P均＜0.01.随时间延长,抑制作用逐渐增强,12～60 h Lg-1处理组对BGC-823的抑制率与Vp-16处理组比较差异有统计学意义,12 h抑制率分别为9.8％和8.0％,P=0.001;24h分别为11.6％和9.0％,P=0.02;36h分别为19.4％和16.2％,P=0.014;48 h分别为44.1％和41.2％,P=0.048;60 h分别为65.4％和50.1％,P=0.001.细胞周期检测显示,Lg-1作用12和24 h后,G2/M期的细胞含量分别为39.37％和74.36％,与对照组及Vp-16组比较均明显增加,而G0/G1期细胞含量分别为20.06％和12.25％,较对照组及Vp-16组显著减少.Hoechst33258染色显示,Lg-1处理组细胞核固缩、碎裂、凋亡样改变,药物处理后Bcl-2 mRNA的表达呈降低趋势,Vp-16处理组Bcl-2 mRNA表达量为0.748,Lg-1处理组为0.425,而p53、Bax、p21和Caspase-3 mRNA的表达呈增高趋势,Vp-16处理组mRNA表达量分别为1.074、1.232、1.818和2.9,Lg-1处理组分别为1.903、1.393、1.911和3.097,且Lg-1处理组作用优于Vp-16处理组.结论:Lg-1可抑制胃癌细胞增殖,使细胞阻滞在G2/M期,该过程可能与其上调p53、Bax、p21、Caspase-3表达和下调Bcl-2基因的表达有关.     

幽门螺杆菌L型感染对胃癌BGC-823细胞增殖的影响

目的:研究幽门螺杆菌L型(helicobacter pylori L-form,Hp-L型)感染对胃癌BGC-823细胞增殖的影响,并探讨其作用机制。方法:将胃癌BGC-823细胞与Hp-L型以不同比例(1:20、1:100、1:500)共培养,以不加Hp-L型为对照组,在不同时段进行以下实验:倒置显微镜观察细胞形态学变化;四甲基噻唑氮蓝(MTT)法检测细胞生长增殖率;流式细胞仪(FCM)检测细胞凋亡率;免疫组化(SP法)检测癌基因(skp2)、抑癌基因(p53)和核增殖指数(Ki-67)的表达情况。结果:Hp-L型作用BGC-823细胞后,倒置显微镜观察到细胞分裂增多,增殖旺盛,瘤巨细胞增多,出现明显的生长加速现象;MTT法测定细胞生长曲线显示,Hp-L型对胃癌BGC-823细胞增殖有促进作用;FCM检测可见,Hp-L型影响胃癌BGC-823细胞周期的分布,使G0/G1期比例降低,S期比例升高;免疫组化可见细胞中Skp2、p53和Ki-67蛋白表达阳性率逐渐增加;以上作用均呈细菌浓度和作用时间依赖性。结论:Hp-L型可促进胃癌BGC-823细胞增殖,其机制与上调Skp2、p53和Ki-67蛋白的表达有关。     

培美曲塞联合奥沙利铂对人胃癌BGC-823细胞生长的影响

目的:探讨培美曲塞与奥沙利铂对人胃癌细胞BGC-823的生长抑制作用以及可能的作用机制。方法:采用不同浓度培美曲塞和奥沙利铂单独或联合作用于BGC-823细胞。应用MTT法检测BGC-823细胞生长抑制率,FCM检测细胞周期的变化,蛋白质印迹法检测增殖细胞核抗原(proliferating cell nuclear antigen,PCNA)和细胞周期蛋白D1(cell cycle D1,cyclinD1)的表达水平。结果:培美曲塞和奥沙利铂均可抑制BGC-823细胞的生长(P<0.05),且呈时间和剂量依赖性。这两种药物均可明显增加G1期细胞比例,降低S期细胞比例。蛋白质印迹法检测结果显示,cyclinD1和PCNA表达量均明显降低,其中培美曲塞和奥沙利铂联合处理具有协同效应,培美曲塞(80μg/mL)处理24h后序贯奥沙利铂(40μg/mL)处理24h组BGC-823细胞的生长抑制率明显高于双药联合处理组以及奥沙利铂(40μg/mL)处理24h后序贯培美曲塞(80μg/mL)处理24h组(P<0.05)。结论:培美曲塞和奥沙利铂均可抑制胃癌细胞BGC-823的生长,细胞被阻滞于G1期。在双药联合处理中,以培美曲塞序贯奥沙利铂对胃癌细胞的生长抑制最强。     

奥曲肽对人胃癌BGC-823细胞增殖和凋亡影响的研究

目的:研究生长抑素类似物奥曲肽(octreotide,OCT)对胃癌BGC-823细胞增殖、凋亡、细胞周期的影响及其可能的作用机制.方法:不同浓度的OCT作用于体外培养的人胃癌BGC-823细胞,以5-FU作为阳性对照,应用MTT法分析细胞增殖的抑制作用,流式细胞仪测定细胞周期分布和凋亡率,AO-EB染色观察细胞形态变化.结果:OCT对BGC-823细胞的生长、增殖产生抑制作用,该抑制作用具有量效、时效关系和饱和性;OCT作用后细胞呈典型的凋亡形态学改变,流式细胞仪检测的细胞凋亡率和AO-EB染色测得细胞凋亡率与对照组相比较差异有显著性(P<0.05);BGC-823细胞经OCT作用后,G1期细胞数明显增加,S细胞数明显减少,细胞被阻滞于G1/S 期.结论:10-5-10-3g/L 浓度的OCT能够抑制胃癌BGC-823细胞增殖,机制可能与其诱导肿瘤细胞的凋亡和出现G1/S期阻滞有关.     

菝葜皂苷元对胃癌BGC-823细胞增殖、凋亡影响的实验研究

目的:观察不同浓度菝葜皂苷元对体外培养胃癌BGC-823细胞增殖、凋亡的影响.方法:BGC-823细胞经不同浓度菝葜皂苷元处理后,采用MTT法检测细胞的生长活性,流式细胞仪检测细胞凋亡.结果:随菝葜皂苷元浓度的增加,胃癌BGC-823细胞增殖抑制率、凋亡率亦升高.结论:菝葜皂苷元对胃癌BGC-823细胞的增殖有抑制作用,并可诱导细胞凋亡.     

奥沙利铂联合替尼泊苷抑制胃癌BGC-823细胞生长和诱导凋亡的作用

目的:探讨奥沙利铂(oxaliplatin, OXA)联合替尼泊苷(teniposide, VM-26)抑制胃癌BGC-823细胞的体外生长及诱导细胞凋亡的作用.方法:应用MTT法检测不同浓度OXA和VM-26单药以及联合用药对胃癌BGC-823细胞生长的抑制作用,应用FCM检测细胞凋亡率,同时应用免疫细胞化学法检测OXA单药以及OXA联合VM-26用药对胃癌BGC-823细胞caspase-9和livin蛋白表达的影响.结果:OXA和VM-26单药均可抑制胃癌BGC-823细胞的生长,且在一定浓度范围内呈剂量依赖效应;联合用药组的细胞生长抑制率明显高于OXA和VM-26单药组,差异有统计学意义(P<0.05),联合指数(combination index, CI)为0.46.OXA(1.250 μg/mL)单药作用于胃癌BGC-823细胞12、24和48 h后,细胞凋亡率分别为6.13%、13.86%和21.48%;VM-26(0.625 μg/mL)单药组的细胞凋亡率分别为4.60%、10.72%和17.07%;联合用药组的细胞凋亡率分别为11.73%、24.14%和44.75%.联合用药组的细胞凋亡率明显高于OXA和VM-26单药组,差异有统计学意义(P<0.05).免疫细胞化学结果显示,OXA(1.250 μg/mL)单用以及联合VM-26(0.750 μg/mL)作用于胃癌BGC-823细胞48 h后,凋亡相关基因caspase-9蛋白的阳性表达率均增加,而livin蛋白的阳性表达率均下降;各用药组之间以及用药组与对照组(未用药)之间的差异均有统计学意义(P<0.05).结论:OXA联合VM-26用药在抑制胃癌BGC-823细胞的生长和诱导细胞凋亡方面具有协同作用.     

细胞周期素D1反义寡核苷酸对胃癌细胞株BGC—823的作用

目的：通过基因反义封闭技术体外抑制细胞周期素D1(cyclin D1)的表达，并对胃癌细胞增殖的影响。方法：以胃腺癌BGC-823细胞株为研究对象，采用硫代修饰的cyclin D1反义寡脱氧核苷酸(ASODN)处理BGC-823细胞后，观察cyclin D1 ASODN对BGC-823细胞基因表达及体外增殖活性的影响。结果：MTT法测细胞增殖活性见不同浓度ASODN均能抑制BGC-823细胞增殖，抑制作用在48小时最强。RT-PCR检测结果cyclin D1 mRNA减少。免疫组化S-P法结果cyclin D1蛋白表达明显降低。结论：使用人工合成的cyclin D1 ASODN可以特异性的抑制胃腺癌BGC-823细胞株cyclin D1的表达，从而调控细胞周期，抑制细胞增殖。     

亚砷酸钠对人胃癌细胞株BGC-823的作用机制

 目的探讨亚砷酸钠对人胃癌细胞株BGC-823的作用机制。方法采用MTT法、光镜、电镜、流式细胞仪检测和免疫细胞化学法研究亚砷酸钠对BGC-823细胞生物学行为的影响。结果不同浓度的亚砷酸钠均可有效抑制BGC-823细胞生长,且具有浓度和时间依赖性,其中效浓度为4.86μmol/L。流式细胞仪检测发现亚砷酸钠作用不同时间后,细胞均出现G2/M期阻滞。形态学观察显示亚砷酸钠作用72h后,细胞出现典型的凋亡和坏死形态学改变。免疫细胞化学法发现亚砷酸钠能显著上调细胞Caspase-3蛋白的表达。结论亚砷酸钠对BGC-823细胞的生长有明显的抑制作用,并可诱导细胞周期阻滞及细胞凋亡和坏死,其机制可能与其抑制ROS的清除,上调Caspase-3蛋白的表达有关。     

Radiation sensitivity of merkel cell carcinoma cell lines

: Merkel cell carcinoma (MCC), being a small cell carcinoma, would be expected to be sensitive to radiation. Clinical analysis of patients at our center, especially those with macroscopic disease, would suggest the response is quite variable. We have recently established a number of MCC cell lines from patients prior to radiotherapy, and for the first time are in a position to determine their sensitivity under controlled conditions.     

桥接整合因子1通过AKT-mTOR通路诱导非小细胞肺癌H1975细胞周期阻滞

目的：研究桥接整合因子1（bridging intergrator 1,Bin1）基因过表达后对非小细胞肺癌细胞株H1975细胞周期的影响及其作用机制。方法：构建携带Bin1基因的CMV-MCS-GFP-SV40-Neomycin-Bin1质粒,并转染H1975细胞（Bin1+组）,另设置空白质粒转染组（Bin1-组）及空白对照组（Ctrl组）,利用RT-PCR和Western blotting分别检测3组细胞中Bin1在mRNA和蛋白质水平的表达情况。流式细胞术检测不同处理组H1975细胞周期的变化,Western boltting分别检测各组中AKT、mTOR磷酸化水平及细胞周期相关蛋白（周期蛋白D1、CDK4、Rb）的表达情况。结果：与Bin1-组、Ctrl组比较,Bin1+组H1975细胞中Bin1在mRNA、蛋白水平表达明显上调（均P<0.05）; H1975细胞阻滞在G1期\[（60.53±1.89）% vs（46.14±1.56）%、（47.33±2.07）%,均P<0.05\]; Bin1+组H1975细胞内p-AKT、p-mTOR表达下调（均P<0.05）,AKT、mTOR表达变化无统计学差异（P>0.05）;周期蛋白D1、CDK4的表达量均明显下调(P<0.05),Rb表达量明显增加（P<0.05）。结论：Bin1基因在H1975细胞株过表达后明显诱导细胞周期阻滞,其机制可能是通过抑制AKT-mTOR通路及其细胞周期相关蛋白实现的。     

Mechanisms of kaposis-sarcoma cell supernatant-induced vascular cell invasion

Kaposi's sarcoma (KS) is a highly angiogenic lesion frequently associated with acquired immune deficiency syndrome. Histologically the lesions appear to contain proliferative 'spindle shaped' cells with a mixed smooth muscle-endothelial-fibroblastic histotype and a conspicuous neovascularization, derived from host cell recruitment. Media conditioned by cultured KS cells (KS-CM) have angiogenic properties. KS-CM is able to promote endothelial and smooth muscle cell migration and invasion. The mechanisms of this KS-CM activity are still unknown. We hypothesize that KS-CM contains numerous factors with different roles in inducing the neo angiogenic process. We show that AIDS-IST-KS cell supernatants induce gelatinase A production and plasminogen activator (PA) up-regulation in vascular cells. KS-CM activity in vivo is heparin dependent. Also bFGF alone, a heparin dependent factor, alone can induce endothelial and smooth muscle cell invasion, MMP-2 production and PA activity. However, antibodies to bFGF do not block KS-CM activity and do not reduce the effect on PA up-regulation. This evidence suggests that heparin-binding factors other than bFGF may be present. Chromatography of KS-CM on heparin-sepharose demonstrates the presence of two heparin-binding fractions with chemotactic and gelatinase A inducing activity. The flow through was also active. KS-CM absorption on heparin-sepharose beads did not modify its induction of PA activity, further evidence for the presence of non heparin-binding factors as well.     

Inhibition of S-adenosylhomocysteine hydrolase decreases cell mobility and cell proliferation through cell cycle arrest

S-adenosylhomocysteine hydrolase (AHCY) hydrolyzes S-adenosylhomocysteine to adenosine and l-homocysteine, and it is already known that inhibition of AHCY decreased cell proliferation by G2/M arrest in MCF7 cells. However, the previous study has not indicated what mechanism the cell cycle arrest is induced by. In this study, we aimed to investigate the different cell cycle mechanisms in both p53 wild-typed MCF7 and p53 mutant-typed MCF7-ADR by suppressing AHCY. We extensively proved that AHCY knockdown has an anti-proliferative effect by using the WST-1 assay, BrdU assay, and cell cytometry analysis and an anti-invasive, migration effect by wound-healing assay and trans-well analysis. Our study showed that down-regulation of AHCY effectively suppressed cell proliferation by regulating the MEK/ERK signaling pathway and through cell cycle arrests. The cell cycle arrest occurred at the G2/M checkpoint by inhibiting degradation of cyclinB1 and phosphorylation of CDC2 in MCF7 cells and at the G1 phase by inhibiting cyclinD1 and CDK6 in MCF7-ADR cells. Finally, we determined that AHCY regulates the expression of ATM kinase that phosphorylates p53 and affects to arrest of G2/M phase in MCF7 cells. The findings of this study significantly suggest that AHCY is an important regulator of cell proliferation through different mechanism in between MCF7 and MCF7-ADR cells as p53 status.     

Landscape of immune cell infiltration in clear cell renal cell carcinoma to aid immunotherapy

The tumor microenvironment, comprised of tumor cells and tumor-infiltrating immune cells, is closely associated with the clinical outcome of clear cell renal cell carcinoma (ccRCC) patients. However, the landscape of immune infiltration in ccRCC has not been fully elucidated. Herein, we applied multiple computational methods and various datasets to reveal the immune infiltrative landscape of ccRCC patients. The tumor immune infiltration (TII) levels of 525 ccRCC patients using a single-sample gene were examined and further categorized into immune infiltration subgroups. The TII score was characterized by distinct clinical traits and showed a significant divergence based on gender, grade, and stage. A high TII score was associated with the ERBB signaling pathway, the TGF-β signaling pathway, and the MTOR signaling pathway, as well as a better prognosis. Furthermore, patients with high TII scores exhibited greater sensitivity to pazopanib. The low TII score was characterized by a high immune infiltration level of CD8⁺ T cells, T follicular helper cells, and regulatory T cells (Tregs). Moreover, the immune check point genes, including CTLA-4, LAG3, PD-1, and IDO1, presented a high expression level in the low TII score group. Patients in the high TII score group demonstrated significant therapeutic advantages and clinical benefits. The findings in this study have the potential to assist in the strategic design of immunotherapeutic treatments for ccRCC.     

肿瘤细胞自噬的诱导及其细胞周期分析

背景与目的:自噬作为Ⅱ型程序性死亡——自噬性死亡过程中的主要现象,与细胞的自噬性死亡有着密切的关系。研究者们对凋亡与细胞周期的关系进行了深入而细致的研究,但对自噬性细胞死亡与细胞周期的关系却知之甚少。本研究的目的是探讨不同方法诱导的细胞自噬与细胞周期之间的关系。方法:用Hanks’液替代培养基的饥饿诱导和用长春新碱诱导两种方法分别处理对数生长期的HeLa细胞、SW480细胞以及经过和未经过植物血凝素(phytohemagglutinin,PHA)刺激的健康人外周血淋巴细胞;应用激光共聚焦显微镜和透射电镜检测细胞自噬的发生,兔抗人微管相关蛋白1轻链3Ⅱ(microtubule-associatedprotein1lightchain3,MAP1-LC3-Ⅱ)/DNA双参数流式细胞术分析自噬细胞的细胞周期。结果:HeLa细胞和SW480细胞用饥饿和长春新碱两种方法诱导的细胞自噬在G1、S、G2/M期均可以发生,且自噬发生率随诱导时间的延长逐渐增加。处于静止期(未经PHA刺激)的外周血淋巴细胞没有自噬的发生,48h时LC3-Ⅱ表达率<2.62%(HanksL液饥饿诱导)或<6.16%(长春新碱诱导);经PHA刺激48h进入细胞周期的外周血淋巴细胞,2h时已有明显的自噬发生。结论:MAP1-LC3-Ⅱ/DNA双参数流式细胞术是对细胞自噬与细胞周期进行同步分析的一种新的简便可靠的方法;细胞自噬只发生在细胞进入周期后,而静止期细胞对自噬诱导因素不敏感。     

NDRG2 suppresses the proliferation of clear cell renal cell carcinoma cell A-498

Background

Recently, the anti-tumor activity of N-myc downstream-regulated gene 2 (NDRG2) was shown decreased expression in clear cell renal cell carcinoma (CCRCC), but the role of the down-expression of NDRG2 has not been described.

Methods

The NDRG2 recombinant adenovirus plasmid was constructed. The proliferation rate and NDRG2 expression of cell infected with recombinant plasmid were mesured by MTT, Flow cytometry analysis and western blot.

Results

The CCRCC cell A-498 re-expressed NDRG2 when infected by NDRG2 recombinant adenovirus and significantly decreased the proliferation rate. Fluorescence activated cell sorter analysis showed that 25.00% of cells expressed NDRG2 were in S-phase compared to 40.67% of control cells, whereas 62.08% of cells expressed NDRG2 were in G1-phase compared to 54.39% of control cells (P < 0.05). In addition, there were much more apoptotic cells in NDRG2-expressing cells than in the controls (P < 0.05). Moreover, upregulation of NDRG2 protein was associated with a reduction in cyclin D1, cyclin E, whereas cyclinD2, cyclinD3 and cdk2 were not affected examined by western blot. Furthermore, we found that p53 could upregulate NDRG2 expression in A-498 cell.

Conclusions

We found that NDRG2 can inhibit the proliferation of the renal carcinoma cells and induce arrest at G1 phase. p53 can up-regulate the expression of NDRG2. Our results showed that NDRG2 may function as a tumor suppressor in CCRCC.