As2O3对人膀胱癌细胞株BIU-87作用的体外研究

目的　观察三氧化二砷 (As2 O3 )对人膀胱癌细胞株BIU 87的作用 ,并探讨其作用机制。方法　采用四氮唑蓝(MTT )法检测As2 O3 不同浓度、不同作用时间对BIU 87细胞株的生长抑制率 ;流式细胞术 (FCM )检测不同浓度As2 O3 作用 72h后细胞中凋亡相关蛋白Fas、bcl 2的表达及细胞周期变化。结果　As2 O3 可有效抑制BIU 87细胞株的生长 ,具有浓度、时间依赖性特点。Fas、bcl 2的表达与As2 O3 浓度增高分别呈正、负相关 (P <0 .0 5 ) ,且随As2 O3 浓度增高Fas、bcl 2的表达呈负相关 (P <0 .0 5 )。随As2 O3 浓度增高细胞周期被阻滞在G0 /G1期。结论　As2 O3 可有效抑制人膀胱癌BIU 87细胞株的生长增殖 ,阻滞细胞周期及诱导细胞凋亡可能起了重要作用     

As2O3对人膀胱癌细胞凋亡和MDR1表达及细胞周期的影响

目的：观察三氧化二砷(As2O3)对人膀胱癌细胞株BIU-87的凋亡诱导作用及对多药耐药基因(MDR1)蛋白表达、细胞周期的影响。方法：采用四氮唑蓝(MTT)法检测As2O3不同浓度、不同作用时间对BIU-87细胞的生长抑制率；流式细胞术(FCM)检测不同浓度As2O3作用72h后细胞中与凋亡有关蛋白Fas、bcl-2及MDR1蛋白表达、细胞周期变化。结果：As2O3可有效抑制BIU-87细胞的生长增殖，与浓度、时间相关，P＜0．05；Fas、bcl-2的表达分别与浓度增高呈正、负相关，P＜0．05，且二者随浓度增高呈负相关，P＜0．05；MDR1蛋白表达与对照组相比As2O3 1 μmol／L作用后升高，P＜0．05，2、5 μmol／L作用后降低，P＜0．05；随As2O3浓度升高，细胞周期被阻滞在G0／G1期。结论：As2O3可有效抑制人膀胱癌细胞的生长增殖，诱导细胞凋亡及阻滞细胞周期可能起了重要作用。     

c-Myc和Fas在三氧化二砷体外诱导HL-60细胞凋亡中的变化与作用的研究

目的:探讨三氧化二砷(As2O3)在体外诱导急性早幼粒白血病(acute promyelo-cytic leukemia,APL)细胞HL-60凋亡的分子机制。方法:采用MTT方法检测As2O3对HL-60细胞增殖的影响,流式细胞术检测细胞周期、细胞凋亡和Fas蛋白表达,RT-PCR检测c-Myc和Fas的mRNA表达。结果:4.0μmol/L的As2O3作用96h可抑制70%的HL-60细胞,并使细胞周期阻滞在G0/G1期,诱导细胞凋亡,P&lt;0.01;Fas蛋白表达升高,作用72h后阳性率由对照组的9.63%增加为32.84%,P&lt;0.01;Fas mRNA表达升高,c-Myc的mRNA表达降低,P&lt;0.01。结论:As2O3诱导HL-60细胞凋亡的机制在于引起细胞周期阻滞,上调Fas蛋白及mRNA表达,下调c-Myc的mRNA表达。     

三氧化二砷对人肝癌细胞生长增殖的影响

目的观察三氧化二砷（As2O3）对人BEL7402肝癌细胞株的作用及其机制。方法采用MTF法检测As2O3对BEL7402细胞的生长抑制率;流式细胞仪测定经不同浓度As2O3处理后的BEL7402细胞周期及增殖细胞核抗原（PCNA）变化,同时Annexin V—FITC／PI双染法检测细胞凋亡。结果三氧化二砷可显著抑制BEL7402细胞生长,且剂量-效应关系显著（r=0．9650,P〈0．01）,半数抑制浓度（IC50）为4．93μmol／L;BEL7402经As2O3处理后可发生凋亡。As2O3能显著下调PCNA蛋白表达（P〈0．01）,并使细胞周期阻滞在G2／M期。结论三氧化二砷可有效抑制人肝癌BEL7402细胞生长增殖,其机制可能与诱导细胞凋亡、下调PCNA表达及阻滞细胞周期有关。     

三氧化二砷对人膀胱癌细胞BIU-87作用的体外研究

目的观察三氧化二砷(arsenic trioxide,As2O3)对人膀胱癌细胞株BIU-87的作用,并探讨其作用机制.方法采用四氮唑蓝(MTT)法检测As2O3不同浓度、不同时间对BIU-87细胞的生长抑制率,同时流式细胞仪检测不同浓度As2O3作用72 h后细胞中与凋亡有关蛋白Fas、Bcl-2的表达.结果As2O3可有效抑制BIU-87细胞的生长,具有浓度、时间依赖性特点.Fas、Bcl-2的表达分别与浓度增加呈正、负相关,P<0.05,且二者随浓度增高呈负相关,P<0.05.结论As2O3可有效抑制膀胱癌细胞生长,其作用机制与凋亡有关.     

蛴螬粗提物对人宫颈癌HeLa细胞诱导凋亡作用及其机制

 目的 研究蛴螬粗提物对人宫颈癌HeLa细胞诱导凋亡作用，并探讨其作用机制。方法 采用流式细胞仪检测HeLa细胞的细胞周期分布相和细胞凋亡率；末端脱氧核苷酸转移酶（TdT）介导的脱氧核苷酸缺口末端标记（TdT mediated dUTP nick end labeling）TUNEL法检测凋亡细胞；通过免疫细胞化学SP法测定凋亡相关基因产物p53、Fas、bcl 2、Bax蛋白的表达情况。结果 (1)蛴螬粗提物可以诱导HeLa细胞发生凋亡，加药组出现亚二倍体峰，并且G0/G1期细胞比例显著增加（P＜0.01），而S期和G2/M期细胞比例则明显下降,将细胞阻滞在G0/G1期；（2）蛴螬粗提物作用细胞后凋亡细胞数目随时间延长而增多，凋亡指数与药物处理呈时间依赖性和剂量依赖性；(3)蛴螬粗提物作用后bcl 2、p53蛋白随提取物浓度表达均下降，Bax、Fas蛋白表达上升，四种蛋白表达各组间比较差异均有具有统计学意义（P<0.01）。结论 (1) 蛴螬粗提物对人宫颈癌HeLa细胞具有诱导凋亡作用；(2)蛴螬粗提取物诱导凋亡作用机制可能与细胞周期发生G0/G1期阻滞有关；并且通过下调bcl 2、p53蛋白表达,上调Bax、Fas蛋白表达，经由细胞凋亡的死亡受体通路和线粒体通路完成凋亡的启动和执行。     

三氧化二砷对人肺腺癌细胞的细胞毒作用及其机制

背景与目的:三氧化二砷(arsenictrioxide,As2O3)应用于急性早幼粒细胞性白血病(acutepromyelocyticleukemia,APL)的临床化疗已显示较好疗效。目前,已开展了将As2O3用于治疗胃癌、头颈部癌和食管癌等实体瘤的实验研究。本研究旨在探讨As2O3对人肺腺癌SPCA1细胞的毒性及其作用机制。方法:MTT法检测As2O3对SPCA1细胞的生长抑制作用;流式细胞术测定经不同浓度As2O3处理后的SPCA1细胞的细胞周期改变、凋亡相关蛋白Fas和Bcl-2阳性细胞百分率及细胞内钙离子(IECa2+)含量变化。结果:As2O3可显著抑制SPCA1细胞生长增殖,且呈剂量-效应关系(r=0.973,P<0.05),其IC50为8.56μmol/L;As2O3能显著增加Fas蛋白表达和IECa2+含量(P<0.05),并使细胞周期阻滞在G2/M期,但对Bcl-2表达无影响(P>0.05)。结论:As2O3对SPCA1细胞有显著的毒性作用,其机制可能与上调Fas表达和增加IECa2+含量及阻滞细胞周期有关。     

三氧化二砷诱导卵巢癌OVCAR-3细胞周期阻滞及凋亡

目的探讨As2O3对卵巢癌细胞增殖的抑制作用及对细胞周期和凋亡的影响.方法采用MTT法及集落形成实验测定细胞的增殖活力,通过细胞形态学观察细胞分裂及凋亡,应用流式细胞仪进行细胞周期解析、凋亡及bcl-2蛋白表达的检测.结果As2O3呈剂量依赖性抑制OVCAR-3细胞增殖,抑制50%细胞生长的药物浓度(IC50)为2μmol/L.0.5～5μmol/L的As2O3作用7天,集落抑制率均在40%以上(P＜0.01).2μmol/L与5μmol/L的As2O3作用12 h后,细胞周期出现了G2/M期阻滞及亚二倍体凋亡峰,随着作用时间的延长,凋亡细胞随G2/M期细胞减少而逐渐增多.细胞形态学观察可见分裂期细胞及凋亡细胞明显增加.0.5～5μmol/L的As2O3均能下调bcl-2蛋白的表达.结论As2O3能够抑制卵巢癌OVCAR-3细胞的增殖,诱导M期阻滞及细胞凋亡.     

三氧化二砷对非M_3的AML及ALL细胞Fas和FasL蛋白影响的研究

 目的　了解As2 O3 对非M3 的急性髓性白血病 (AML)及急性淋巴细胞性白血病 (ALL)细胞Fas、FasL蛋白的影响。方法　将非M3 的AML细胞和ALL细胞体外与不同浓度As2 O3 共同培养 ,通过细胞计数、细胞活力的判定并利用流式细胞仪检测DNA、Fas和FasL蛋白的变化 ,来观察As2 O3 对上述细胞的细胞活力、增殖周期及Fas、FasL蛋白的影响。结果　随着As2 O3 浓度由 0 μmol/L增加至2 μmol/L ,细胞活力由 (91.1± 2 .3) %降至 (6 4 .32± 3.5 ) % ;细胞生长抑制率由 (10 .6± 1.6 ) %增至(2 9.36± 2 .6 ) % ;细胞凋亡率由 (0 .0 7± 2 .5 ) %增至 (5 .0 4± 2 .2 ) % ;随着As2 O3 浓度增加 ,Fas、FasL的阳性率也随之增加。结论　As2 O3 以浓度依赖的方式抑制非M3 的AML及ALL细胞的生长、活力及细胞周期 ,使G0 G1期细胞增多 ,As2 O3 在诱导非M3 的AML及ALL细胞发生凋亡的同时 ,可以上调Fas、FasL的表达 ,提示Fas/FasL系...     

柠檬酸钠联合三氧化二砷体外抗人胃癌细胞及其作用机制

目的探讨柠檬酸钠（Citrate）与三氧化二砷（As2O3）联合应用对胃癌细胞的凋亡及其作用机制。方法用Citrate（终浓度为5 mmol/L）和（或）不同浓度的As2O3（终浓度依次为5、10 μmol/L）处理体外传代培养的胃癌细胞株SGC-7901和BGC-803。流式细胞仪检测细胞凋亡和细胞周期的变化;RT-PCR法观察凋亡相关基因Bcl-2、Mcl-1表达的变化。结果Citrate与As₂O3联合应用相对于单用Citrate或As₂O3可显著提高诱导胃癌细胞凋亡率（P<0.05）;与空白组相比,用药后 G0／G₁期细胞比例下降,G₂/M期细胞比例上升,细胞周期阻滞于G₂/M期,抗凋亡基因Bcl-2、Mcl-1表达明显下降。结论Citrate与As2O3联合应用具有协同抗胃癌细胞的作用,其机制可能与细胞周期阻滞、增强诱导胃癌细胞凋亡以及调控凋亡相关基因的表达有关。     

Biomarkers in clear cell renal cell carcinoma

The treatment of advanced renal cell carcinoma (RCC) has evolved significantly following the identification of the von Hippel–Lindau (VHL) gene and the function of its protein, and subsequent development of antiangiogenic therapies. A series of clinical trials resulted in the approval of three new agents with significant activity in this disease. Additional studies are now underway to identify subsets of patients most likely to benefit. This article reviews the current therapy for advanced RCC and the development of biomarkers in RCC. This requires the identification of disease characteristics at a clinical, genetic and molecular level associated with response and/or surrogate measures of clinical benefit. Currently, a variety of prognostic factors (lactate dehydrogenase, performance status, disease-free interval, hemoglobin and calcium levels) are utilized to predict the survival of RCC patients. The use of validated biomarkers in either serum/plasma, urine or tissue could enhance this process, as well as define at the molecular and genetic levels, factors associated with response to therapy and/or the development of resistance. Examples include plasma VEGF levels, VHL gene mutation status and carbonic anhydrase IX levels in tumor tissue, among others. Validation of such biomarkers is crucial in order for them to be clinically useful.     

Biomarkers in clear cell renal cell carcinoma

The treatment of advanced renal cell carcinoma (RCC) has evolved significantly following the identification of the von Hippel-Lindau (VHL) gene and the function of its protein, and subsequent development of antiangiogenic therapies. A series of clinical trials resulted in the approval of three new agents with significant activity in this disease. Additional studies are now underway to identify subsets of patients most likely to benefit. This article reviews the current therapy for advanced RCC and the development of biomarkers in RCC. This requires the identification of disease characteristics at a clinical, genetic and molecular level associated with response and/or surrogate measures of clinical benefit. Currently, a variety of prognostic factors (lactate dehydrogenase, performance status, disease-free interval, hemoglobin and calcium levels) are utilized to predict the survival of RCC patients. The use of validated biomarkers in either serum/plasma, urine or tissue could enhance this process, as well as define at the molecular and genetic levels, factors associated with response to therapy and/or the development of resistance. Examples include plasma VEGF levels, VHL gene mutation status and carbonic anhydrase IX levels in tumor tissue, among others. Validation of such biomarkers is crucial in order for them to be clinically useful.     

Non-small and small cell lung carcinoma cell lines exhibit cell type-specific sensitivity to edelfosine-induced cell death and different cell line-specific responses to edelfosine treatment

The unique signal transduction pathways that distinguish non-small cell lung carcinoma (NSCLC) from small cell lung carcinoma (SCLC) are poorly understood. We investigated the ability of edelfosine, an inhibitor of phosphatidylinositol-specific phospholipase C (PLC) to inhibit cell viability among four NSCLC cell lines and four SCLC cell lines. The differential sensitivity of cells to edelfosine's cytostatic and cytotoxic effects has been attributed to edelfosine-induced changes in the activities of many enzymes, including c-Jun NH2-terminal kinase (JNK), extracellular signal-regulated kinases (ERK), p38 kinase, and poly(ADP-ribose) polymerase (PARP). To investigate the role of these enzymes in edelfosine-induced cytotoxicity, we correlated edelfosine-induced changes in enzyme activity and cell viability among the different NSCLC and SCLC cell lines. We found that NSCLC cells are much more susceptible to the cytotoxic effects of this drug than are SCLC cells. Three out of the four edelfosine-sensitive NSCLC cell lines (NCI-H157, NCI-H520, NCI-H522) exhibit G2/M arrest, significant apoptosis and some degree of JNK activation in response to drug treatment. In contrast, none of the SCLC cell lines exhibit edelfosine-induced G2/M arrest or significant apoptosis. A comparison of the edelfosine-induced effects among the sensitive and resistant lung cancer lines indicates that there is little correlation between edelfosine-induced cytotoxicity and altered activities of JNK, ERK, p38, or cleavage of PARP. These results demonstrate that edelfosine-induced changes in JNK, ERK, p38, or PARP are not good predictors of cell susceptibility to edelfosine-induced cytotoxicity. Thus, edelfosine-induced inactivation of PLC may disrupt signaling cascades downstream of PLC that are unique to individual cellular environments. These findings also identify edelfosine as one of the few potential chemotherapeutic agents that has a greater cytotoxic effect against NSCLC cells than SCLC cells.     

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。     

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.