Apg-2基因沉默对BaF3-MIGR1及BaF3-P210细胞增殖的影响

目的探讨Apg-2基因沉默对pMIGR1空载体感染的BaF3-MIGR1细胞及稳定表达Bcr-Abl融合基因的BaF3-P210细胞增殖的影响,为进一步研究Apg-2在Bcr-Abl阳性的CML细胞中的作用奠定基础。方法针对Apg-2基因609～629、845～865和2 110～2 130核苷酸合成3条shRNA序列Hspa41、Hspa42、Hspa43,同时合成阴性对照序列HspaHK,电穿孔转染BaF3-MIGR1和BaF3-P210细胞,经G418筛选稳定抑制细胞株,RT-PCR和Western blot检测细胞中Apg-2基因mRNA的转录水平及蛋白的表达水平;Am-blue法检测细胞增殖;甲基纤维素法检测细胞克隆形成能力;流式细胞技术检测细胞周期的变化。结果转染的3条shRNA质粒中,shRNA-Hspa42的干扰效果最佳。Apg-2表达抑制后,BaF3-P210细胞的增殖与克隆形成能力均明显下降(P<0.05),处于G1期细胞的百分率明显升高(P<0.05),处于S期的细胞百分率明显下降(P<0.05);而BaF3-MIGR1细胞的增殖与克隆形成能力均明显增强(P<0.05),处于S期的细胞百分率明显升高(P<0.05)。结论干扰Apg-2基因的表达可抑制Bcr-Abl阳性细胞BaF3-P210的增殖,而对Bcr-Abl阴性细胞BaF3-MIGR1的增殖起促进作用。     

Apg-2过表达对BaF3-MIGR1及稳定表达BCR/ABL的BaF3-P210细胞增殖的影响

目的探讨热休克蛋白Apg-2过表达对小鼠pMIGR1空载体感染细胞BaF3-MIGR1和BCR/ABL转化细胞BaF3-P210(简称BP210)增殖的影响。方法构建pIERS2-EGFP-Apg-2真核表达质粒,电穿孔转染BaF3-MIGR1和BP210细胞,经G418筛选稳定表达细胞株,分别用RT-PCR和Western blot鉴定Apg-2的表达。采用Am-Blue法和流式细胞仪(FCM)检测Apg-2过表达对BaF3-MIGR1和BP210细胞增殖的影响,光镜观察细胞形态变化。结果pIERS2-EGFP-Apg-2真核表达质粒构建正确,转染细胞后筛选到稳定过表达Apg-2的BaF3-MIGR1-Apg-2和BP210-Apg-2细胞株,BaF3-MIGR1-Apg-2细胞的增殖速度明显低于BaF3-MIGR1细胞,BP210-Apg-2细胞比BP210细胞增殖加快。光镜下可见Apg-2过表达的两种细胞形态发生变化,瑞氏染色可见细胞核增多。结论Apg-2能够促进BCR/ABL阳性细胞的增殖,可能与慢性粒细胞白血病的发生发展相关。     

H_2O_2对Apg-2与BCR/ABL蛋白亚细胞定位的影响

目的观察H2O2对Apg-2与BCR/ABL蛋白亚细胞定位的影响。方法用50μmol/L H2O2分别处理BaF3-BCR/ABL、BaF3-MIGR1及过表达Apg-2蛋白的BaF3-BCR/ABL细胞,激光共聚焦显微镜观察细胞内Apg-2、BCR/ABL蛋白的亚细胞定位变化。结果 Apg-2和BCR/ABL蛋白在细胞中定位于胞浆,H2O2损伤可致Apg-2和BCR/ABL蛋白在BaF3-BCR/ABL细胞中发生核转位,Apg-2蛋白过表达可引起BCR/ABL蛋白核转位。结论 Apg-2蛋白在H2O2诱导的损伤后发生核转位,可能与BCR/ABL蛋白相互作用,保护H2O2诱导的细胞损伤。     

鹿茸多肽对辐射诱导神经母细胞瘤细胞调亡后Bax和Bcl-2表达的影响

目的探讨鹿茸多肽对辐射诱导神经母细胞瘤细胞调亡后B淋巴细胞瘤-2(B-cell lymphoma-2,Bcl-2)基因和Bcl-2相关X蛋白(Bcl-2 associated X protein,Bax)基因表达的影响。方法将神经母细胞瘤经X射线2 Gy照射5 min,诱导细胞凋亡后,用400和800 mg/ml鹿茸多肽溶液处理细胞,同时设未处理细胞作为对照组。采用RTPCR法检测Bcl-2、Bax基因mRNA转录水平。结果与对照组相比,鹿茸多肽400、800 mg/ml处理组Bcl-2、Bax基因mRNA转录水平均上调(P均<0.05);800 mg/ml处理组Bcl-2基因mRNA转录水平高于400 mg/ml处理组,而800 mg/ml处理组Bax基因mRNA转录水平低于400 mg/ml处理组,但两组间差异均无统计学意义(P>0.05)。结论鹿茸多肽对神经母细胞瘤细胞的凋亡具有明显的抑制作用,其抑制细胞凋亡的作用是通过上调Bcl-2表达、下调Bax表达实现的。     

联氨基姜黄素对乳腺癌细胞MCF-7增殖和凋亡的影响及其机制

目的探讨联氨基姜黄素对人乳腺癌细胞MCF-7增殖和凋亡的影响及其机制。方法采用MTT法检测联氨基姜黄素对MCF-7细胞的抗增殖效应,Hochest33258染色观察细胞形态学变化,流式细胞术分析细胞的周期分布和凋亡情况,Western blot检测MCF-7细胞中Bcl-2、Bax、Cyclin D1和Survivin蛋白的表达变化。结果联氨基姜黄素可抑制MCF-7细胞的增殖,IC50为2.56μmol/L,而姜黄素的IC50为21.22μmol/L;联氨基姜黄素染色24 h后,MCF-7细胞出现核荧光强度增强、颗粒状荧光等凋亡特征;凋亡细胞比率明显增加,并可阻滞细胞周期于G1期,且呈一定的剂量依赖性;联氨基姜黄素可使MCF-7细胞中Bcl-2、Cyclin D1、Survivin蛋白表达水平明显降低,而Bax表达增加。结论联氨基姜黄素具有抑制MCF-7细胞增殖、促进凋亡、阻滞细胞周期于G1期的作用,其机制可能与Bcl-2、Bax、Cyclin D1、Survivin蛋白的表达改变有关。     

邻苯二甲酸二(2-乙基)己酯诱导隐睾对SD幼鼠睾丸生殖细胞凋亡的影响

目的探讨环境内分泌干扰物邻苯二甲酸二(2-乙基)己酯[D(i2-ethylhexy1)phthalate,DEHP]作用于SD孕鼠后,对哺乳期雄性幼鼠睾丸组织中生殖细胞凋亡及凋亡基因Bax和Bcl-2表达的影响。方法将30只妊娠第12.5天的SD孕鼠随机分正常对照组、玉米油对照组和DEHP诱导隐睾组,每组10只。玉米油对照组和DEHP诱导隐睾组自妊娠第12.5～19.5天分别每日灌胃玉米油(2 ml)和DEHP(500 mg/kg),正常对照组不给药。取各组出生后第20天的雄性幼鼠睾丸组织,采用Q-PCR法检测睾丸组织中Bax和Bcl-2基因的水平,流式细胞术检测睾丸生殖细胞的凋亡情况。结果 DEHP诱导隐睾组幼鼠睾丸组织中Bax基因mRNA的水平显著高于两对照组(P<0.000 1),Bcl-2基因mRNA的水平显著低于两对照组(P<0.01);DEHP诱导隐睾组幼鼠睾丸生殖细胞凋亡百分率显著高于两对照组(P<0.000 1)。结论孕期暴露环境内分泌干扰物DEHP可引起雄性子代发生隐睾,且隐睾鼠睾丸生殖细胞凋亡率增加,隐睾子代睾丸组织中凋亡基因Bax和Bcl-2的表达有改变,推测其改变可能参与了生殖细胞的凋亡过程,并可能与隐睾继发的远期不育有关。     

木香烃内酯对肝癌SMMC-7721细胞凋亡的影响及其作用机制

目的 探讨木香烃内酯（costunolide,Cos）对肝癌SMMC-7721细胞凋亡的影响及其作用机制。方法 将SMMC-7721细胞随机分为对照组、10、20、30μmol/L Cos剂量组。采用流式细胞术检测Cos对SMMC-7721细胞凋亡的影响,Western blot检测SMMC-7721细胞中凋亡相关蛋白（Bax、Bcl-2、Caspase-3）及内质网应激（endoplasmic reticulum stress,ERS）通路相关蛋白（GRP78、CHOP、ATF4）的表达水平。结果 10、20和30μmol/L Cos剂量组SMMC-7721细胞凋亡率（apoptosis rate,AR）均明显高于对照组（P <0.05）,且各Cos剂量组SMMC-7721细胞AR随剂量增加明显上升（P <0.01）。与对照组比较,20和30μmol/L Cos剂量组SMMC-7721细胞中Bcl-2蛋白表达水平明显降低（P <0.05）,Bax蛋白表达水平均明显增加（P <0.05）,10μmol/L Cos剂量组的Bcl-2及Bax蛋白表达水平差异无统计学...     

不同剂量瑞芬太尼对缺血再灌注时大鼠肾细胞凋亡和bcl-2、bax表达的影响

目的观察不同剂量瑞芬太尼对大鼠肾缺血再灌注后肾小管细胞凋亡及其调控基因bcl-2和bax表达的影响,探讨瑞芬太尼肾保护作用的分子生物学机制。方法用动脉夹夹闭大鼠双侧肾蒂45min再灌注6h方法制成急性肾缺血再灌注损伤模型。采用脱氧核苷酸末端转移酶介导的DNA原位末端标记技术检测细胞凋亡的情况。免疫组化检测Bcl-2、Bax基因表达。结果缺血再灌注组较假手术组肾小管凋亡细胞数明显增多,Bcl-2、Bax表达均增强,Bax/Bcl-2比值增高;瑞芬太尼各剂量处理组较缺血再灌注组凋亡细胞数明显减少,Bcl-2表达进一步增强,而Bax表达减弱,Bax/Bcl-2降低。结论瑞芬太尼可能通过上调Bcl-2基因表达,下调Bax基因表达,抑制细胞凋亡,从而发挥对缺血再灌注损伤肾脏的保护作用。     

秦巴硒菇提取物FA-2-b-β对伯基特淋巴瘤Raji细胞增殖及凋亡的影响及其作用机制

目的观察秦巴硒菇提取物酸性RNA蛋白复合物FA-2-b-β对伯基特淋巴瘤细胞株Raji增殖及凋亡的影响,并探讨其相关作用机制。方法体外培养Raji细胞,分别加入浓度为0.9、1.5、2.1、2.7 mg/mL的FA-2-b-β,对照组加入等量培养基。培养24、48、72 h后收集各组细胞,采用CCK-8法检测FA-2-b-β对Raji细胞的增殖抑制作用;流式细胞仪检测细胞凋亡率;Western blot法检测细胞β-catenin、c-myc、cyclin D1、Bcl-2、Bax蛋白的表达。结果 FA-2-b-β能抑制Raji细胞增殖,且呈浓度-时间依赖性(P 0.01);给药48 h后,各浓度FA-2-b-β组细胞凋亡率较对照组均显著上升,且呈剂量依赖性(P 0.05);各浓度FA-2-b-β组细胞β-catenin、c-myc、cyclin D1、Bcl-2蛋白的表达水平显著低于对照组,且呈剂量依赖性(P 0.05),Bax蛋白表达水平显著高于对照组,同样呈剂量依赖性(P 0.05),Bax/Bcl-2比值增加。结论 FA-2-b-β呈时间-剂量依赖性诱导伯基特淋巴瘤凋亡,可能与Wnt/β-catenin信号通路相关。     

过表达BRIT1基因对鼻咽癌HNE-1细胞凋亡的影响及其机制

目的研究BRIT1(BRCT-repeat inhibitorof h TER expression)基因对鼻咽癌HNE-1细胞凋亡的影响,并初步探讨其相关的分子机制。方法利用免疫组织化学法检测30份鼻咽癌组织及30份鼻咽正常组织中BRIT1蛋白的表达;利用质粒pc DNA3.1(-)/BRIT1及pc DNA3.1转染HNE-1细胞,TUNEL法、Hoechst33342染色法及流式细胞术检测细胞的凋亡情况,Western blot法检测转染细胞中BRIT1蛋白及caspase-3、active caspase-3、Bax、bcl-2蛋白的表达。结果 BRIT1在鼻咽癌组织中的BRIT1蛋白表达水平低于鼻咽正常组织(P0.05);转染质粒pc DNA3.1(-)/BRIT1的HNE-1细胞中,BRIT1蛋白水平明显上调(P0.05);过表达BRIT1明显促进HNE-1细胞的凋亡,并导致抗凋亡蛋白caspase-3、bcl-2表达下调(P0.05),促凋亡蛋白active caspase-3、Bax表达上调(P0.05)。结论BRIT1基因通过调控线粒体凋亡途径相关基因的表达,促进鼻咽癌细胞HNE-1凋亡的发生。     

Exogenous and Endogeneous Disialosyl Ganglioside GD1b Induces Apoptosis of MCF-7 Human Breast Cancer Cells

Gangliosides have been known to play a role in the regulation of apoptosis in cancer cells. This study has employed disialyl-ganglioside GD1b to apoptosis in human breast cancer MCF-7 cells using exogenous treatment of the cells with GD1b and endogenous expression of GD1b in MCF-7 cells. First, apoptosis in MCF-7 cells was observed after treatment of GD1b. Treatment of MCF-7 cells with GD1b reduced cell growth rates in a dose and time dependent manner during GD1b treatment, as determined by XTT assay. Among the various gangliosides, GD1b specifically induced apoptosis of the MCF-7 cells. Flow cytometry and immunofluorescence assays showed that GD1b specifically induces apoptosis in the MCF-7 cells with Annexin V binding for apoptotic actions in early stage and propidium iodide (PI) staining the nucleus of the MCF-7 cells. Treatment of MCF-7 cells with GD1b activated apoptotic molecules such as processed forms of caspase-8, -7 and PARP (Poly(ADP-ribose) polymerase), without any change in the expression of mitochondria-mediated apoptosis molecules such as Bax and Bcl-2. Second, to investigate the effect of endogenously produced GD1b on the regulation of cell function, UDP-gal: β1,3-galactosyltransferase-2 (GD1b synthase, Gal-T2) gene has been transfected into the MCF-7 cells. Using the GD1b synthase-transfectants, apoptosis-related signal proteins linked to phenotype changes were examined. Similar to the exogenous GD1b treatment, the cell growth of the GD1b synthase gene-transfectants was significantly suppressed compared with the vector-transfectant cell lines and transfection activated the apoptotic molecules such as processed forms of caspase-8, -7 and PARP, but not the levels of expression of Bax and Bcl-2. GD1b-induced apoptosis was blocked by caspase inhibitor, Z-VAD. Therefore, taken together, it was concluded that GD1b could play an important role in the regulation of breast cancer apoptosis.     

Butin (7,3',4'-Trihydroxydihydroflavone) Reduces Oxidative Stress-Induced Cell Death via Inhibition of the Mitochondria-Dependent Apoptotic Pathway

Recently, we demonstrated that butin (7,3',4'-trihydroxydihydroflavone) protected cells against hydrogen peroxide (H(2)O(2))-induced apoptosis by: (1) scavenging reactive oxygen species (ROS), activating antioxidant enzymes such superoxide dismutase and catalase; (2) decreasing oxidative stress-induced 8-hydroxy-2'-deoxyguanosine levels via activation of oxoguanine glycosylase 1, and (3), reducing oxidative stress-induced mitochondrial dysfunction. The objective of this study was to determine the cytoprotective effects of butin on oxidative stress-induced mitochondria-dependent apoptosis, and possible mechanisms involved. Butin significantly reduced H(2)O(2)-induced loss of mitochondrial membrane potential as determined by confocal image analysis and flow cytometry, alterations in Bcl-2 family proteins such as decrease in Bcl-2 expression and increase in Bax and phospho Bcl-2 expression, release of cytochrome c from mitochondria into the cytosol and activation of caspases 9 and 3. Furthermore, the anti-apoptotic effect of butin was exerted via inhibition of mitogen-activated protein kinase kinase-4, c-Jun NH(2)-terminal kinase (JNK) and activator protein-1 cascades induced by H(2)O(2) treatment. Finally, butin exhibited protective effects against H(2)O(2)-induced apoptosis, as demonstrated by decreased apoptotic bodies, sub-G(1) hypodiploid cells and DNA fragmentation. Taken together, the protective effects of butin against H(2)O(2)-induced apoptosis were exerted via blockade of membrane potential depolarization, inhibition of the JNK pathway and mitochondria-involved caspase-dependent apoptotic pathway.     

Mitochondrial Cholesterol Transporter,StAR, Inhibits Human THP-1 Monocyte-Derived Macrophage Apoptosis

Steroidogenic acute regulatory protein (StAR) plays an important role in the maintenance of intracellular lipid homeostasis. Macrophages are the key cellular player in the pathophysiology of atherosclerosis. Imbalance of macrophage lipid homeostasis causes cellular apoptosis, which is the key process in the initiation of atherosclerosis. The present study has investigated the effects of StAR in the apoptotic process of human THP-1 derived macrophages induced by serum withdrawal or Ox-LDL. Overexpression of StAR significantly decreased the number of apoptotic macrophages by decreasing the expression of pro-apoptotic genes Caspase-3 and Bax mRNA and protein levels, as well as through increasing expression of anti-apoptotic gene Bcl-2 mRNA and protein levels in the absence and presence of Ox-LDL. The results indicate that StAR plays an important role in macrophage and foam cell apoptotic processing, which may provide a potential method for preventing atherosclerosis.     

PML(NLS~-)干扰对HL-60细胞增殖与凋亡的影响

目的探讨缺失核定位信号的PML,即PML(NLS-)干扰对急性早幼粒细胞白血病细胞HL-60增殖与凋亡的影响。方法将靶向PML(NLS-)基因的3组干扰质粒pGpu6-PML(NLS-)shRNA和阴性对照质粒pGpu6-NCshRNA分别转染HL-60细胞,转染后48 h,G418筛选阳性克隆,分别命名为Si-1、Si-2、Si-3和NC组,并设空白对照组。采用RT-PCR法和Western blot法检测各组细胞中PML(NLS-)基因mRNA的转录水平和蛋白的表达水平;MTT法检测细胞的增殖活力;流式细胞术分析细胞的细胞周期及凋亡情况。结果 Si-1和Si-2组HL-60细胞PML(NLS-)基因mRNA的转录水平和蛋白的表达水平与空白对照组相比明显减低(P<0.05),有干扰效果;Si-1组HL-60细胞的增殖水平与空白对照组相比明显降低(P<0.05),以转染后48 h降低最为显著(P<0.01);抑制PML(NLS-)表达可引起HL-60细胞S期比例增高,G1和G2期比例下降(P<0.05);Si-1组细胞凋亡率明显高于NC组和空白对照组(P<0.05)。结论干扰PML(NLS-)的表达可促进HL-60细胞的凋亡,抑制其增殖。     

Pharmacological Effects of Guava (Psidium guajava L.) Seed Polysaccharides: GSF3 Inhibits PC-3 Prostate Cancer Cell Growth through Immunotherapy In Vitro

The inhibitory effects of purified fractions isolated from guava seed polysaccharides (GSPS) including guava seed polysaccharide fraction 1 (GSF1), GSF2, and GSF3 on prostate cancer cells remain unclear. To clarify the anti-prostate cancer potential, GSPS, GSF1, GSF2, and GSF3 were isolated using Sepharose 6B gel filtration chromatography to assay their inhibitory effects on prostate PC-3 cell growth with direct action or indirect immunotherapy using either splenocyte conditioned media (SCM) or macrophage conditioned media (MCM). Correlations between cytokine profiles in the conditioned media and pro-apoptotic gene expression levels in the corresponding treated PC-3 cells were analyzed. Results showed that GSPS, GSF1, GSF2, and GSF3, particularly GSF3, through either direct action or indirect treatments using SCM or MCM, significantly (p < 0.05) inhibited PC-3 cell growth. GSF3 direct treatments increased pro-apoptotic Bax/anti-apoptotic Bcl-2 mRNA expression ratios in corresponding treated PC-3 cells. Either SCM or MCM cultured with GSF3 increased Fas mRNA expression levels in corresponding treated PC-3 cells. Both Th2-polarized and anti-inflammatory cytokine IL-10 either secreted in SCM or MCM were positively correlated with Fas mRNA expression levels in corresponding treated PC-3 cells. Our results suggest that GSF3 is a potent biological response modifier to decrease PC-3 cell growth through inducing apoptosis.