顺铂增强食管癌相关基因2蛋白对人食管癌EC9706细胞的增殖抑制和凋亡诱导作用

 摘要：目的:探讨食管癌相关基因2（esophageal cancer-related gene 2,ECRG2）蛋白联合顺铂（cisplatin, DDP）化疗对人食管癌EC9706细胞增殖和凋亡的影响。方法:采用MTT法分别检测单用ECRG2蛋白和ECRG2蛋白联合顺铂对EC9706细胞增殖的影响;采用Hoechst 33258染色法检测二者对EC9706细胞凋亡的影响;Western blotting检测二者对EC9706细胞中p53蛋白表达的影响。结果:MTT结果显示,ECRG2蛋白可抑制EC9706细胞增殖,ECRG2蛋白和DDP联用后抑制细胞增殖作用增强,且在一定浓度范围内呈时间、剂量依赖关系。Hoechst 33258染色显示,ECRG2蛋白和DDP联合作用24 h后EC9706细胞凋亡数目多于单用ECRG2蛋白。Western blotting结果提示ECRG2蛋白和DDP联合用药较单用ECRG2蛋白明显上调p53蛋白的表达。结论: DDP 可增强ECRG2蛋白对人食管癌EC9706细胞的增殖抑制和凋亡诱导作用,其增强诱导EC9706细胞凋亡的机制可能与上调p53蛋白的表达有关。     

脉冲电场联合野生型p53基因诱导人宫颈癌Hela细胞凋亡

背景：在前期研究基础上,设想将基因电转染作为脉冲电场治疗恶性肿瘤的辅助方法。 目的：探讨脉冲电场联合抑癌基因野生型p53基因诱导人宫颈癌hela细胞发生凋亡及相互作用。 方法：采用空质粒及含有野生型p53的质粒转染Hela细胞得到Hela-vector、Hela-p53细胞,将Hela细胞、Hela-vector和Hela-p53细胞分别施加固定脉宽100 μs、频率1 Hz、脉冲数8个、电场强度为1 500 V/cm的脉冲电场处理。 结果与结论：相同参数脉冲电场作用于各组细胞12 h后,MTT结果显示Hela-p53组细胞吸光度明显低于Hela组(P < 0.05);流式细胞仪及RT-PCR检测结果显示Hela-p53组的早期凋亡率和p53 mRNA表达较Hela组明显增加;Western bolt及激光共聚焦显微镜结果显示与Hela组比较,Hela-p53组细胞Bax蛋白表达明显上升,而Bcl-2蛋白则明显下降,Casepase-3相对荧光强度明显增强。表明野生型p53基因对宫颈癌Hela细胞生长有明显的抑制作用,野生型p53基因可以提高脉冲电场诱导宫颈癌Hela细胞凋亡的作用。     

白藜芦醇联合顺铂对神经胶质瘤细胞的作用

目的： 探讨白藜芦醇联合顺铂对神经胶质瘤细胞C6 的作用。方法：不同浓度的白藜芦醇与顺铂单独联合 作用于神经胶质瘤细胞C6,24、48 h 和72 h 后,CCK8法检测增殖,并选出合适浓度进行后续试验;不同浓度的 药物作用于细胞24 h 后,吖啶橙法观察细胞形态变化、流式细胞仪检测细胞凋亡、细胞周期和免疫印迹检测蛋白 Bax、Bcl-2 和p-Erk1/2 变化。结果：白藜芦醇与顺铂能协同抑制神经胶质瘤细胞C6 的增殖。联合用药后细胞周 期抑制在S 期。免疫印迹结果显示凋亡蛋白Bax 的表达量增加,而凋亡抑制蛋白Bcl-2 的表达量减少,细胞外调 节蛋白激酶p-Erk1/2 的表达量减少。结论：白藜芦醇与顺铂联合对神经胶质瘤细胞具有相互增敏作用,能够协同 抑制细胞增殖,并通过Ras-Raf-MEK-Erk 信号通路促进其凋亡。     

DIM增强顺铂抑制PC-3细胞增殖及诱导凋亡的效应

目的：观察顺铂(DDP)和3，3-二吲哚基甲烷(3,3-diindolylmethane ,DIM)联合应用对人前列腺癌PC-3细胞增殖和凋亡的影响。方法:采用MTT法检测PC-3细胞增殖抑制情况，用流式细胞术及吖啶橙染色法分析细胞凋亡的变化，用RT-PCR检测抑癌基因p21的表达变化。结果:60 μmol.L-1的DIM 与0.4 mg·L^-1的DDP 联合可有效抑制PC-3细胞增殖并诱导其凋亡，其效果与单用4 mg·L-1DDP相同。DIM与DDP联合试验中细胞生长抑制率和凋亡率也明显高于单用DIM处理组（P＜0.05）。RT-PCR结果表明：单用DIM和DIM与DDP联合用药都能明显增强p21基因的表达，但联合用药的效果更明显。结论:DIM能显著增强DDP对PC-3细胞的增殖抑制和诱导凋亡的效应。     

虫草素增强顺铂诱导的食管癌细胞系Eca109凋亡

目的研究虫草素与顺铂联合用药对食管癌细胞Eca109凋亡的影响及其作用机制。方法将食管癌细胞Eca109分为对照组、不同浓度虫草素处理组、不同浓度顺铂处理组和虫草素(70μg/m L)与顺铂(0.8μg/m L)联合处理组。MTS法检测Eca109细胞增殖;Hoechst 33258染色法及流式细胞术检测Eca109细胞凋亡;Western blot法检测细胞核内NF-κB P65及凋亡相关蛋白Bcl-2和Bax表达水平;ELISA法检测细胞核内NF-κB P65与DNA的结合活性。结果虫草素与顺铂联合应用使顺铂对Eca109细胞的抑制率由29.30%增加至70.41%(P0.05),增强了顺铂对Eca109的敏感性;与顺铂单独用药相比,联合用药能够显著增加顺铂诱导的细胞凋亡(P0.05);与对照组相比顺铂能够增加细胞核内NF-κB P65的活性,而虫草素却能抑制NF-κB P65的活性,联合用药后NF-κB P65的活性下调;与虫草素和顺铂单独用药相比,联合用药组能够使抗凋亡蛋白Bcl-2的表达显著降低(P0.05),而促凋亡蛋白Bax表达则显著增高(P0.05)。结论虫草素可能通过抑制NF-κB途径,调节下游信号分子Bcl-2和Bax的表达,增强顺铂对Eca109的凋亡诱导效应。     

雷帕霉素抑制人多囊肾囊肿衬里上皮细胞增殖及VEGF表达

目的 探讨雷帕霉素对常染色体显性多囊肾病囊肿衬里上皮细胞增殖及血管内皮细胞生长因子（VEGF）表达的抑制作用及其机制。方法MTT法检测WT9-12细胞增殖;流式细胞术检测细胞周期及凋亡;Western Blot检测周期相关蛋白(cyclinD、p21)、凋亡相关蛋白(Bcl2/Bax)及VEGF表达。结果 雷帕霉素可抑制WT9-12细胞的增殖,使细胞周期停滞在G0/G1期并促进细胞凋亡。雷帕霉素可下调WT9-12细胞cyclinD 、上调p21表达,下调Bcl2、上调Bax表达。原代培养的多囊肾囊肿衬里上皮细胞及WT9-12细胞的VEGFmRNA表达明显高于正常肾小管上皮细胞（P<0.05）。雷帕霉素可抑制WT9-12细胞VEGF的表达（P<0.05）。结论 雷帕霉素可通过抑制多囊肾囊肿衬里上皮细胞增殖、促进凋亡及抑制VEGF表达抑制血管形成,从而抑制多囊肾病进展。     

磷酸化修饰对p53线粒体作用的影响以及与卵巢癌顺铂耐药的关系

目的探讨磷酸化修饰对p53直接线粒体转移的影响以及在顺铂诱导的卵巢癌细胞凋亡中的作用以及与卵巢癌顺铂耐药的关系。方法应用Western Blot检测顺铂作用前后卵巢癌顺铂敏感细胞OV2008、A2780s和顺铂耐药细胞C13＊、A2780cp的线粒体和细胞浆中Smac蛋白含量以及线粒体和全细胞中磷酸化p53（P-p53）的含量,并应用Hoechst染色法检测卵巢癌细胞的凋亡率。结果顺铂能引起卵巢癌敏感细胞OV2008、A2780s线粒体释放Smac至胞浆并引起细胞凋亡,但在C13＊和A2780cp中无此反应。顺铂处理后进入卵巢癌敏感细胞线粒体中的p53蛋白为磷酸化的p53。结论顺铂能引起p53转移至线粒体并导致卵巢癌敏感细胞线粒体释放Smac至胞浆,促进卵巢癌细胞的凋亡,并且磷酸化修饰作用可以影响p53的直接线粒体功能,与卵巢癌化疗耐药有关。     

顺铂通过p66Shc-线粒体信号通路诱导人肾小管上皮细胞凋亡

 目的：探讨p66Shc-线粒体信号通路在顺铂诱导的人肾小管上皮细胞凋亡中的作用。方法：体外培养人肾小管上皮细胞,Western blotting法检测顺铂对p66Shc及磷酸化p66Shc(Ser36)蛋白表达的影响,然后将细胞分为对照组、顺铂组及顺铂+p66ShcS36A（第36位Ser突变为Ala的p66Shc）组,用激光共聚焦显微镜观察p66Shc对顺铂诱导的细胞活性氧簇、线粒体活性氧簇及细胞凋亡的影响,Western blotting法检测线粒体凋亡信号通路相关蛋白的表达。结果：顺铂促进p66Shc蛋白磷酸化,对p66Shc蛋白表达无影响;顺铂诱导细胞凋亡,细胞及线粒体活性氧簇产生增加,细胞色素C释放,caspase-9表达增加,p66ShcS36A可以抑制顺铂诱导的细胞氧化损伤及凋亡。结论：顺铂通过p66Shc-线粒体信号通路诱导人肾小管上皮细胞凋亡。     

p53依赖的X-连锁凋亡抑制蛋白调节与卵巢癌顺铂耐药的关系

目的本研究旨在探讨X-连锁凋亡抑制蛋白（XIAP）在卵巢癌顺铂耐药中的作用。方法应用RT—PCR、Western Blot、流式细胞仪等检测卵巢癌顺铂敏感细胞株0V2008、A2780s和耐药株C13＊、A2780cp中XIAP表达和卵巢癌细胞的凋亡率,并将反义XIAP寡核苷酸（XIAPAs—ODN）、正义XIAP寡核苷酸（XIAPs—ODN）和随机对照链导入顺铂耐药细胞C13＊（p53野生型）和A2780cp（p53突变型）中,比较转染前、后耐药细胞Caspase-3活性和顺铂耐药性的改变。结果卵巢癌顺铂敏感细胞和耐药细胞中XIAP在mRNA水平的表达无明显差异（P〉0．05）。顺铂可以引起OV2008和A2780s中XIAP蛋白表达明显下降（P〈0．05）,而对C13＊和A2780cp的XIAP蛋白含量无明显影响（P〉0．05）。转染XIAPAs—ODN可降调p53野生型耐药细胞C13＊中XIAP的表达,并显著增加Caspase-3活性和对顺铂敏感性（P〈0．05）,而XIAP As—ODN对p53突变型耐药细胞A2780cp无此作用。结论卵巢癌细胞对顺铂产生耐药可能与XIAP蛋白相对高表达有关,反义XIAP可在一定程度上逆转卵巢癌顺铂耐药,该作用与卵巢癌细胞的p53表型有关。     

下调HIPK2基因表达促进顺铂诱导的肾小管上皮细胞HKC凋亡

目的探讨HIPK2对顺铂诱导的人肾小管上皮细胞(HKC)凋亡的影响。方法构建顺铂诱导的HKC细胞凋亡模型,实时荧光定量PCR和Western blot检测HIPK2的表达;设计合成2条HIPK2 siRNA干扰片段,通过脂质体转染HKC细胞,建立HIPK2干扰的细胞株;实时荧光定量PCR和Western blot分别检测HIPK2 mRNA和蛋白的表达;再用顺铂处理细胞,Annexin V/PI检测细胞凋亡;Western blot检测Bax表达的影响。结果顺铂呈剂量依赖性诱导的HKC细胞凋亡过程中,HIPK2 mRNA和蛋白表达水平均明显下调(P0.05);转染siRNA后可显著降低HIPK2在HKC细胞内mRNA和蛋白的表达(P0.05),且HIPK2表达降低后会促进顺铂诱导的HKC细胞凋亡。结论HIPK2可抑制顺铂诱导的HKC细胞凋亡。     

唑来膦酸抑制U937细胞增殖及诱导凋亡

目的:研究唑来膦酸(ZOL)对人类急性髓系白血病细胞U937的增殖抑制及促凋亡作用。方法:CCK-8法检测不同时间ZOL对U937细胞的生长抑制率;流式细胞术检测ZOL对U937细胞周期的影响;Annexin V-PI法及Hoechst 33342法检测ZOL作用前后细胞凋亡情况变化,JC-1检测ZOL对U937细胞线粒体膜电位变化的影响;克隆形成实验检测U937细胞克隆形成能力;Western blot法检测ZOL对U937细胞周期和凋亡相关蛋白的变化。结果:CCK-8结果显示ZOL可以抑制U937细胞的活力,并呈时间-剂量依赖性;Annexin V-PI及Hoechst33342结果显示ZOL可以促进U937细胞凋亡,且呈时间-剂量依赖性;JC-1结果显示ZOL可以明显降低U937细胞线粒体膜电位;PI法证实ZOL将U937细胞周期阻滞在S期,克隆形成实验证实0.2 mmol/L ZOL可以完全抑制U937细胞的克隆形成能力;Western blot结果显示ZOL作用于U937细胞48 h后细胞周期相关蛋白p21表达显著增强,促凋亡蛋白Bax表达增强,抑凋亡蛋白Bcl-2表达明显减弱。结论:ZOL抑制U937细胞的增殖和克隆形成主要是由于抑制了细胞周期相关蛋白表达,同时ZOL可以促进U937细胞凋亡,这种作用主要是通过调节线粒体凋亡途径相关蛋白来实现的。     

Apoptosis-related factors p53, Bcl2, and Bax in neuroendocrine lung tumors.

Neuroendocrine (NE) lung tumors comprise four classes of progressive aggressiveness for which proliferation and apoptosis rates could both contribute to their distinctive behavior. As p53 mutations may favor escape from apoptosis through changes in Bcl2-Bax expression balance, which are survival and apoptotic genes, respectively, we studied 121 NE lung tumors (16 typical carcinoids (TC), 5 atypical carcinoids (AC), 29 large-cell NE carcinomas (LCNECs), and 71 small-cell lung carcinomas (SCLCs) using immunohistochemistry. We quantified apoptosis by terminal-deoxynucleotidyl-transferase-mediated deoxyuridine triphosphate nick end labeling (TUNEL) in 31 of these cases. There was a significant increase of p53 mutant immunophenotype (defined as immunoreactivity with at least two antibodies for at least 20% of tumor cells) between atypical/typical carcinoids group and the LCNEC/SCLC group (P = 0.0003). There was an inverse correlation (P < 0.0001) between the scores of Bax and Bcl2 expression in individual tumors and a significant inversion of the Bcl2. Bax ratio between low-grade (typical and atypical carcinoids) and high-grade (LCNECs and SCLCs) tumors with a predominant Bax expression in the first group and predominant Bcl2 expression in the second. Whereas carcinoids had variable apoptotic indexes, LCNECs had high indexes (1.3 to 6.8%), Bcl2 overexpression, Bax down-regulation, and Bcl2.Bax ratio > 1 correlated with lower apoptotic index in both LCNEC and the pool of LCNECs and SCLCs (P < 0.05) and a lower survival rate in the group of atypical and typical carcinoids and LCNECs (P < 0.002). The highest levels of Bcl2 expression and Bcl2.Bax ratios were associated with p53 mutant immunophenotype (P = 0.02). Our results suggest that aggressiveness in NE lung tumors could be linked, in addition to proliferation, to apoptosis-related factors.     

Hoechst 33342 induces apoptosis in HL-60 cells and inhibits topoisomerase I in vivo.

CONTEXT: Bisbenzimides (Hoechst 33342 and Hoechst 33258) are cell-permeable, adenine-thymine-specific dyes that bind to the minor groove of DNA and stain DNA. Hoechst 33342 induces apoptosis in BC3H-1 myocytes and hepatoma cells. OBJECTIVE: To determine if Hoechst 33342 or Hoechst 33258 induces apoptosis in human promyelocytic leukemia cells (HL-60) and inhibits topoisomerase I activity. DESIGN: A variety of methods were used to detect apoptosis: cell viability (trypan blue exclusion), nuclear fluorescence staining (Hoechst 33342 or Hoechst 33258 stained for 10 minutes), flow cytometric quantitation of annexin binding to phosphatidylserine, and DNA fragmentation (agarose gel electrophoresis). Topoisomerase I activity was determined by a plasmid unwinding assay. SETTING: A large teaching hospital and research laboratories. PATIENTS: None. INTERVENTION: None. MAIN OUTCOME MEASUREMENTS: Apoptosis is characterized by decreased cell viability, condensation of nuclear chromatin, increased phosphatidylserine translocation, and DNA fragmentation into oligonucleosomes composed of multiples of 180 to 200 base pairs. Inhibition of endogenous nuclear topoisomerase I is detected by the absence of plasmid unwinding from a tightly coiled to relaxed form. RESULTS: Hoechst 33342, but not Hoechst 33258, induced apoptosis in the HL-60 cells in a time- and dose-dependent manner. Endogenous nuclear topoisomerase I activity in HL-60 cells was inhibited by treatment with Hoechst 33342 but not Hoechst 33258. CONCLUSION: Hoechst 33342-induced HL-60 cell apoptosis may be related to the dye's inhibition of topoisomerase I activity.     

Cytotoxicity and apoptosis induction in human breast adenocarcinoma MCF-7 cells by (+)-cyanidan-3-ol

The objective of this study was to evaluate the cytotoxicity and possible signalling pathway implicated in (+)-cyanidan-3-ol (CD-3) induced apoptosis in the human breast adenocarcinoma cell line (MCF-7). The effects of CD-3 on cell proliferation of MCF-7 cells were evaluated by 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyl-tetrazolium bromide (MTT), sulforhodamine B (SRB) and lactate dehydrogenase (LDH) assays. Cell apoptosis was detected by Hoechst 33258 (HO) and acridine orange/ethylene dibromide (AO/EB) staining and DNA fragmentation analysis. The expressions of apoptosis-related genes were assessed by RT-PCR and ELISA. Our data revealed that CD-3 induced MCF-7 cell death in a dose-dependent manner. Marked changes in apoptotic morphology was clearly observed after CD-3 treatment. CD-3 induced cell death was considered to be apoptotic by observing the typical apoptotic morphological change under fluorescent microscopy and DNA fragmentation assays. The induction of apoptosis is correlated with the increased mRNA expressions of p53, Bax, and caspase-3, -7, -8 and -9 and decreased mRNA expressions of bcl-2. Subsequently, CD-3 decreased the mRNA expressions of mdm2, p65, c-jun, c-fos in MCF-7 cells. The protein levels of p53, Bax, and caspase-3 were increased, whereas, that of p65, c-jun and Bcl-2 were decreased in MCF-7 cells on CD-3 treatment. These results clearly demonstrated that CD-3 effectively induced growth inhibition and apoptosis in MCF-7 cells.     

Mitochondrial membrane potential change induced by Hoechst 33342 in myelogenous leukemia cell line HL-60

Abstract. Hoechst 33342's effects on apoptosis and mitochondrial membrane potential (delta psi) were investigated in a myelogenous leukemia cell line, HL-60. Delta psi was detected with 2 lipophilic cationic fluorochromes: 3,3'-dihexyloxacarbocyanine iodide [DiOC6(3)] or 5,5',6,6'-tetrachloro-1,1',3,3'-tetraethylbenzimidazolylcarbocyanine iodide (JC-1). Mitochondrial mass was measured with nonyl acridine orange (NAO). Protonophore carbonyl cyanide m-chlorophenylhydrazone (CCCP) depolarized mitochondria in control experiments. Cell viability was determined by propidium iodide uptake. Hoechst 33342 at 10-20 mg/L decreased fluorescence for DiOC6(3) at 0.5 hr. The fluorescence partially normalized at 3 hr and then progressively decreased at 5-24 hr, resulting in cell shrinkage and death. Mitochondrial mass decreased 40-70% by 1 hr and 70-90% at 24 hr. A lower concentration of Hoechst 33342, 5 mg/L, reduced the delta psi at 0.5 hr, but delta psi returned to control values after 3 hr. Mitochondrial mass decreased 30-40% and then partially normalized, and cell viability was > 92% at 24 hr. Protonophore carbonyl cyanide m-chlorophenylhydrazone lowered delta psi with little cell death. Thus, at high concentration, Hoechst 33342 induces depolarization of delta psi and subsequent apoptosis. Lack of apoptosis at low concentration of Hoechst 33342, despite depolarization of delta psi, indicates that mitochondrial membrane depolarization alone is insufficient to induce apoptosis.     

肠道病毒71型诱导Bax依赖的细胞凋亡

目的研究肠道病毒71型（EV71）诱导细胞凋亡的分子机制。方法采用CCK8比色法检测EVT1感染对于人横纹肌肉瘤细胞RD增殖的影响,通过Hoechst33342染色和Caspase3活性测定检测细胞凋亡特征,用WesternBlot方法检测凋亡相关蛋白Caspase3和8的激活。同时通过免疫共沉淀检测EV71感染后细胞内Bax的活化。结果EV71感染RD细胞可以明显抑制细胞增殖,引起Caspase3、8和PARP蛋白的激活,同时引起Bax蛋白表达增加并发生构象变化。结论EV71通过Bax构象变化诱导Caspase依赖的细胞凋亡。     

靶向着丝粒蛋白A的小RNA干扰对肝癌细胞株HepG2细胞生物学行为的影响

目的 研究靶向着丝粒蛋白A(CENP-A)的siRNA对肝癌细胞株HepG2细胞生物学行为的影响.方法 设计并合成三对CENP-A编码基因的反向重复序列,中间间隔9个核苷酸序列,通过定向克隆至载体pSilencerTM 2.1-U6 neo,构建siRNA真核表达质粒,经稳定转染HepG2细胞后检测肝癌细胞中CENP-A基因mRNA及蛋白质表达的抑制情况;通过观察HepG2细胞生长、凋亡、细胞周期和平板克隆形成能力评价CENP-A基因干扰对细胞生物学行为的影响;通过检测bcl-2、Bax、p21waf1、mdm2、p53蛋白表达水平初步探讨CENP-A生物学作用的可能机制.结果 三对靶向CENP-A的siRNA干扰片段中有二对抑制效果明显.与未转染组及空载体组相比,转染CENP-A干扰片段的细胞生长减慢,平板克隆形成率下降.细胞周期检测显示,G1期阻滞(P＜0.01),S期细胞比例减少(P＜0.001).细胞凋亡比例增加(P=0.003),并伴随bcl-2蛋白表达明显下降(P=0.000),Bax蛋白表达明显增高(P=0.001).还可致p21waf1表达增高,mdm2表达下降,但对野生型p53表达未显示明显影响.结论 CENP-A通过参与细胞周期调控而密切相关于细胞恶性增殖和凋亡抑制,其机制可能涉及野生型p53非依赖性通路和凋亡相关基因bcl-2Bax的表达异常.