23-羟基白桦酸诱导LoVo细胞凋亡与细胞内活性氧的关系

目的： 研究23-羟基白桦酸诱导人结肠癌细胞株LoVo细胞凋亡过程中活性氧（ROS）的变化及其作用机制。方法：光学显微镜法观察23-羟基白桦酸作用LoVo细胞后细胞形态学改变，并采用流式细胞仪检测细胞凋亡及细胞内ROS水平。结果：分别以浓度为25、50、100、200 μmol/L 23-羟基白桦酸作用LoVo细胞48h后，在光学显微镜下观察到明显的凋亡细胞形态学改变；经流式细胞仪检测，细胞凋亡率分别为(7.17±2.31)%、(15.60±4.02)%、(32.47±5.25)%及(52.71±5.93)%，呈现一定的浓度依赖性关系。23-羟基白桦酸可使 LoVo 细胞内ROS的水平明显高于空白对照组。细胞内ROS含量（MFI，平均荧光强度）分别为2.83±0.80、5.97±1.72、12.53±2.57及16.73±4.58。其中，浓度为100和200 μmol/L 23-羟基白桦酸的作用较明显，与对照组(2.13±0.32)比有显著差异（P<0.05）。结论：23-羟基白桦酸具有明显的诱导LoVo细胞凋亡作用，其作用机制可能与23-羟基白桦酸引起细胞内ROS水平增加有关。     

浅蓝菌素对人结肠癌细胞LoVo在裸鼠体内生长的抑制作用

目的 研究脂肪酸合酶抑制剂－浅蓝菌素对人结肠癌细胞ＬｏＶｏ在裸鼠体内生长的抑制作用。方法 建立人结肠癌裸鼠移植瘤模型,浅蓝菌素每次８０ｍｇ／ｋｇ体重、１６０ｍｇ／ｋｇ体重腹腔注射１０次,动态观察肿瘤体积及抑瘤率,治疗后１７ｄ处死并解剖动物,瘤组织做形态学观察和免疫组织化学ＳＰ法检测。结果 不同浓度浅蓝菌素处理人结肠癌细胞ＬｏＶｏ裸鼠移植瘤模型,低剂量和高剂量浅蓝菌素的体积抑瘤率分别为３７．７％和６３．８％,后者接近常规化疗药物５－Ｆｕ治疗对照组（６５．８％）。瘤体组织学显示为人未分化结肠腺瘤,浅蓝菌素处理的移植瘤组织内瘤细胞出现明显的细胞凋亡的超微结构改变,免疫组织化学显示ｂｃ１－２蛋白表达率低于对照组,ｂａｘ基因蛋白的表达结果则相反。结论 浅蓝菌素能够选择性地抑制人结肠癌细胞ＬｏＶｏ细胞在裸鼠体内的生长,这种     

重症肌无力患者胸腺细胞凋亡障碍与Fas表达异常的关系

目的 :探讨重症肌无力 (MG)胸腺细胞凋亡异常、Fas表达异常在自身免疫应答形成中的作用。方法 :用手术切除的MG患者的胸腺 ,制备胸腺提取液和胸腺细胞悬液 ,用MTT比色法测定胸腺细胞的增殖 ;用DNA电泳及细胞形态学观察细胞凋亡 ;用流式细胞仪检测细胞表面Fas的表达 ,用RT PCR结合单链多态构象性分析 (SSCP) ,探讨Fas基因的转录及可能存在的Fas基因突变。结果 :MG患者的胸腺提取液 ,能抑制正常胸腺细胞增殖 ,但不能抑制MG患者胸腺细胞增殖。在地塞米松作用下 ,正常人及患者胸腺细胞的增殖均可被抑制 ,细胞增殖抑制率分别为 5 8.33%和 5 4 .2 6 %。MG患者胸腺细胞的DNA电泳可见梯状条带 ,并且胸腺细胞上Fas的表达百分率增加 [(2 0 .38± 6 .0 7) % ],与空白对照组 [(12 .4 3±4 .32 ) % ]相比较P <0 .0 5。对MG患者胸腺细胞FasmRNA进行RT PCR SSCP分析 ,部分MG患者出现异常电泳条带。结论 :MG患者胸腺细胞的凋亡及Fas分子表达均异常 ,而且存在Fas基因突变 ,提示与本病的发生发展有关。     

CD40配体对结肠癌细胞株的体外抑制作用

研究免疫共刺激分子CD40在结肠癌细胞株的表达及重组可溶性人CD40配体(rshCD40L)对结肠癌细胞株的体外抑制作用。采用流式细胞仪分别检测4株结肠癌细胞(HCT116、Caco-2、SW48和COLO-320)CD40分子的表达,同时利用流式细胞仪检测γ干扰素(IFN-γ)对结肠癌细胞株CD40表达的影响。MTT法检测rshCD40L对结肠癌细胞的抑制作用,TUNEL法检测rshCD40L对结肠细胞的促凋亡作用,同时检测联合rshCD40L和IFN-γ抗结肠癌作用。结果流式细胞仪检测有3株结肠癌细胞(HCT116、Caco-2和SW48)表达CD40分子,IFN-γ能增强CD40+结肠癌细胞CD40分子的表达。rshCD40L能明显抑制CD40+结肠癌细胞的增殖作用(抑制率分别为HCT116:33.5%±5.5%;Caco-2:21.5%±3.6%;SW48:30.1%±4.2%),而对CD40-结肠癌细胞株(COLO-320)无明显抑制作用(P<0.05)。rshCD40L能诱导CD40+结肠癌细胞的凋亡作用(凋亡细胞百分比为HCT116:25.6%±4.52%;Caco-2:15.71%±2.27%;SW48:18.0%±3.7%),而对CD40-结肠癌细胞株(COLO-320)无诱导凋亡作用(P<0.05)。另外,IFN-γ能明显增强rshCD40L对结肠癌细胞的抑制增殖和促凋亡作用。重组人CD40配体与IFN-γ联合可显著诱导CD40阳性的结肠癌细胞凋亡,抑制其增殖,具有潜在的抗肿瘤作用。     

蛋白酶体抑制剂MG132对NK/T淋巴瘤细胞增殖、凋亡和细胞周期的影响

目的： 探讨蛋白酶体抑制剂MG132（Z-leu-leu-leu-CHO,三肽基乙醛）对NK/T淋巴瘤细胞的增殖和细胞周期分布的影响,研究蛋白酶体抑制剂MG132治疗NK/T细胞淋巴瘤的潜在应用价值。方法: 用蛋白酶体抑制剂MG132处理细胞,噻唑蓝［ 3（4,5二甲基噻唑2）2,5二苯基四氮唑溴盐,3-(4,5-dimethylthiazol-2-yl)-2,5- diphenyltetrazolium bromide,MTT］法检测细胞增殖抑制率,倒置显微镜观察细胞形态改变,流式细胞仪检测细胞周期分布和凋亡。结果: 1 μmol/L MG132作用24 h,HANK1细胞增殖抑制率为（57.72±7.44）%,而0.1 μmol/L MG132作用24 h,增殖抑制率仅为（3.98±0.07）%;MG132剂量大,增殖抑制率高;1 μmol/L MG132作用24 h后,HANK1细胞G1和G2期细胞分别为（72.33±3.44）%和（12.86±1.29）%,对照组为（63.63±2.29）%和（7.94±1.91）%,用药组G1和G2期细胞明显高于对照组（P<0.01,P<0.05）; 早期凋亡细胞和晚期凋亡细胞分别为（33.57±2.10）%和（16.66±0.47）%,而对照组仅为（7.18±0.82）%和（3.81±1.06）%,与对照组相比,凋亡率明显增高 (P<0.01,P<0.01)。结论: MG132抑制NK/T细胞淋巴瘤细胞增殖,使细胞周期G1和G2期阻滞,促进细胞凋亡,并存在剂量和时间依赖关系,蛋白酶体抑制剂MG132很可能成为治疗进展期NK/T细胞淋巴瘤的药物。     

5-氟脲嘧啶与γ-干扰素作用于Lovo细胞的实验观察

目的观察5-氟脲嘧啶与γ-干扰素联合应用对人结肠癌Lovo细胞株的影响。方法采用Lovo结肠癌细胞体外培养,流式细胞仪检测细胞生长、增殖和凋亡的变化。结果 5-氟尿嘧啶与γ-干扰素联合应用后,细胞增殖率下降指数为0.82～1.99,而细胞凋亡率增加指数为2.48～4.89。结论 5-氟尿嘧啶与γ-干扰素联合应用可降低肿瘤细胞的增殖和提高肿瘤细胞的凋亡。     

蟾蜍灵对结肠癌SW-480细胞polo-like kinase-1表达及细胞凋亡的影响

目的：观察蟾蜍灵对人结肠癌细胞系增殖的抑制作用，并探讨其作用机理。 方法： 采用不同浓度的蟾蜍灵作用结肠癌SW-480细胞后，采用MTT法检测细胞的恶性增殖，分别采用琼脂糖凝胶电泳和流式细胞仪检测凋亡情况，分别采用Western blotting、Northern blotting分别检测polo-like kinase-1 (PLK1)蛋白、mRNA水平。 结果： 蟾蜍灵能抑制结肠癌细胞的恶性增殖，且与浓度相关。蟾蜍灵能诱导结肠癌细胞凋亡，且呈浓度依赖性。流式细胞仪检测发现，蟾蜍灵将细胞阻滞在G2/M期。蟾蜍灵能下调结肠癌PLK1蛋白、mRNA水平，且呈药物浓度和作用时间依赖性。 结论： 蟾蜍灵有效地抑制结肠癌SW-480细胞增殖，其机制可能与其下调PLK1表达，从而诱导凋亡有关。     

全反式维甲酸对人结肠癌LoVo细胞化疗药物敏感性及Survivin基因表达的影响

目的 探讨全反式维甲酸(ATRA)对人结肠癌LoVo细胞化疗药物敏感性及Survivin表达的影响,为ATRA的临床应用提供理论依据.方法 应用流式细胞仪检测经不同浓度(10-5、10-6、10-7mol/L)的ATRA作用不同时间(24、48、72 h及第5、9、15天)后结肠癌LoVo细胞的周期变化.将细胞分为AT...     

艰难梭菌毒素B诱导结肠癌细胞凋亡及相关机制研究

目的检测艰难梭菌毒素B(TcdB)对结肠癌SW480细胞增殖与凋亡的影响,研究其引起细胞凋亡的相关机制。方法采用不同浓度的TcdB处理SW480细胞,采用MTT法检测细胞增殖情况;用流式细胞术检测细胞的凋亡及线粒体膜电位变化情况。结果TcdB显著抑制了结肠癌SW480细胞的增殖,作用48 h后的抑制率为46.36%,呈一定的时间-浓度相关性;流式细胞仪检测结果表明,浓度为800 ng/ml的TcdB作用48 h,SW480细胞凋亡率为20.83%,呈一定的时间-浓度相关性。结论艰难梭菌毒素B能够抑制结肠癌SW480细胞增殖、诱导细胞凋亡,其机制可能与启动线粒体凋亡途径有关。     

P38激酶介导胆红素诱导的SHSY5Y细胞凋亡

观察P38激酶在胆红素诱导神经细胞凋亡中的作用 ,探讨参与此过程的信号转导通路。将胆红素 (2× 1 0 -2g L)直接作用于体外培养的人神经母细胞瘤细胞系SHSY5Y ,利用Hochest332 58染色在荧光显微镜下观察细胞核的形态是否发生凋亡样改变 ;用P38激酶抑制剂SB2 0 3580预处理细胞后 ,在倒置光显微镜下观察胆红素作用不同时间细胞形态的变化及存活情况 ;利用流式细胞仪检测细胞凋亡率的改变。结果显示SHSY5Y细胞经胆红素作用后细胞核出现典型的凋亡样改变 ;细胞经SB2 0 3580预处理 1h ,胆红素作用 3h后凋亡率为 (1 2 1± 2 4) % ,对照组为(1 9 4± 2 7) % ;4h后凋亡率为 (39 3± 4 8) % ,对照组为 (66 2± 5 2 ) % ,差异有显著性意义 (P <0 0 1 )。提示P38激酶参与了胆红素诱导SHSY5Y细胞凋亡的信号转导过程     

8-硝基白杨素对人宫颈癌Hela细胞增殖和凋亡的影响

目的：观察8-硝基白杨素(8-NOChR)抑制体外培养人宫颈癌Hela细胞增殖和诱导凋亡作用。方法：体外培养人宫颈癌Hela细胞系细胞。MTT比色法测定Hela细胞增殖活性。软琼脂培养克隆形成法检测Hela细胞集落形成能力。AO/EB染色荧光显微镜观察Hela细胞凋亡形态学改变。DNA凝胶电泳观察梯形DNA条带。结果：MTT比色测定显示,8-NOChR抑制Hela细胞增殖,呈剂量依赖性。软琼脂培养克隆形成法检测表明,8-NOChR显著抑制Hela细胞集落形成,呈剂量依赖性。AO/EB染色荧光显微镜观察发现,8-NOChR诱导Hela细胞呈现典型凋亡细胞形态特征。8-NOChR（30μmol/L）处理Hela细胞72h,琼脂糖凝胶电泳出现“梯形”DNA条带。结论：8-NOChR具有抑制人宫颈癌Hela细胞增殖和诱导细胞凋亡作用     

Induction of apoptosis by S-allylmercapto-L-cysteine, a biotransformed garlic derivative, on a human gastric cancer cell line

Epidemiological and experimental carcinogenesis studies provide evidence that certain components of garlic have anti-cancer activity. Although the biotransformed garlic derivative S-allylmercapto-L-cysteine (SAMC) has been reported to show an inhibitory effect on tumorigenesis, the mechanisms are poorly understood. The present study investigated the effect of SAMC on the growth of human gastric cancer SNU-1 cells. Upon treatment with SAMC, a concentration-dependent inhibition of cell proliferation was observed and cells developed many of the hallmark features of apoptosis, including DNA fragmentation and an increase in the sub-diploid population. The anti-proliferative and apoptotic effect of SAMC was associated with the induction of Bax, p53, and caspase-9, rather than the induction of Bcl-2 and p21. Mitochondrial cytochrome c activation and an in vitro caspase-3 activity assay demonstrated that the activation of caspases accompanies the apoptotic effect of SAMC, which mediates cell death. These results suggest that the apoptotic effect of SAMC on gastric cancer SNU-1 cells may be connected with caspase-3 activation through the induction of Bax and p53, rather then Bcl-2 and p21.     

芹菜素对人肺癌A549细胞凋亡及相关蛋白Bax、Bcl-2表达的影响

目的研究芹菜素对人肺癌 A549细胞增殖抑制和凋亡诱导作用与 Bax、Bcl-2蛋白表达的影响。方法10~80μmol/L 不同浓度芹菜素作用 A549细胞,采用 MTT 法检测芹菜素对 A549细胞增殖抑制作用;Hoechst 33258细胞核染色法观察芹菜素诱导细胞凋亡形态学的变化;流式细胞仪 AnnexinV- FITC/PI 双染色法检测细胞凋亡率;Western blot 法检测凋亡相关蛋白 Bax 和 Bcl-2表达的变化。结果 MTT 法显示,芹菜素对 A549细胞有显著的增殖抑制作用（P <0.01）,且具浓度和时间依赖性;荧光显微镜下观察到芹菜素处理组细胞出现典型的凋亡形态学改变：细胞核固缩、染色质凝集和核碎片化等;流式细胞仪分析结果显示,芹菜素呈浓度依赖性诱导 A549细胞凋亡;Western blot结果显示,促凋亡蛋白 Bax 随着芹菜素浓度升高表达增加,抗凋亡蛋白 Bcl-2随着芹菜素浓度升高表达减少。结论芹菜素具有抑制人肺癌 A549细胞增殖,诱导其凋亡的作用,其机制可能与上调 Bax 蛋白表达和下调 Bcl-2蛋白表达有关。     

槲皮素对人卵巢癌SKOV-3细胞增殖的影响

 目的：探讨槲皮素对人卵巢癌SKOV-3细胞增殖抑制和凋亡的影响,为卵巢癌临床治疗提供依据。方法：不同浓度槲皮素处理卵巢癌SKOV-3细胞后,采用MTT实验检测细胞增殖抑制作用并计算抑制率,细胞免疫化学染色法鉴定细胞凋亡,流式细胞术检测细胞周期及细胞凋亡。结果：槲皮素能够抑制SKOV-3细胞的增殖,且呈时间和剂量依赖性,免疫荧光显示槲皮素对SKOV-3细胞具有诱导凋亡作用,流式细胞术显示SKOV-3细胞被阻滞在S期, G2/M期细胞比例降低,凋亡率上升。结论：槲皮素在体外能够抑制卵巢癌SKOV-3细胞的增殖,阻止细胞由S期向G2期移行,促进其凋亡。     

肝癌的细胞凋亡及其紫杉醇的诱导作用研究

目的研究肝癌发生过程中原位细胞凋亡活动以及紫杉醇对肝癌细胞系BEL-7404诱导细胞凋亡的作用。方法用脱氧核糖核酸末端转移酶介导的缺口末端标记法检测了肝细胞癌的细胞凋亡,用紫杉醇处理培养细胞BEL-7404、显微镜下进行观察并且进行琼脂糖电泳。结果癌旁组织的原位凋亡细胞增多,紫杉醇处理肝癌细胞可以诱导细胞产生典型的细胞凋亡形态学变化。DNA发生断裂,琼脂糖电泳产生梯形条带。结论在体内肿瘤细胞凋亡降低,细胞分裂可能加快,肿瘤发生。在癌旁组织中细胞凋亡增多,在体外紫杉醇可以诱导肝癌细胞系BEL-7404凋亡。     

RNA interference-mediated silencing of the p53 tumor-suppressor protein drastically increases apoptosis after inhibition of endogenous fatty acid metabolism in breast cancer cells

Fatty acid synthase (FAS)-dependent endogenous fatty acid synthetic activity is abnormally elevated in a biologically-aggressive subset of breast carcinomas. Remarkably, tumor-associated FAS hyperactivity represents a novel target for anti-metabolic therapy because pharmacological inhibitors of FAS are selectively cytotoxic for tumor cells, triggering their apoptotic cell death. Since the p53 tumor-suppressor protein (TP53) is thought to play a novel role in cellular responses of a variety of non-genotoxic metabolic stresses, we characterized the involvement of TP53 in the response of breast cancer cells to FAS inhibition. MCF-7 breast cancer cells were selected for study because they have an intact TP53 pathway and undergo little apoptosis following FAS blockade. Two chemically distinct inhibitors of FAS (the natural mycotoxin cerulenin and the novel small-molecule inhibitor C75) were studied in parallel to provide a broad picture of consequences suffered by the loss of FAS function on TP53 signaling. Treatment with either cerulenin or C75 induced TP53 protein accumulation at 24 h in MCF-7 cells. To determine whether the up-regulation of TP53 following exposure to cerulenin or C75 was solely due to inhibition of endogenous fatty acid metabolism, we first evaluated the cytotoxic response to chemical FAS blockers on MCF-7 cells in which FAS gene expression was previously silenced by using the highly sequence-specific mechanism of RNA interference. MCF-7 cells became insensitive to C75-induced cytotoxicity when the expression of FAS was specifically suppressed by targeted knock-down with small interfering RNA (siRNA), whereas they partially retained their sensitivity to cerulenin. These results demonstrate that C75-induced cytotoxic damage to breast cancer cells is closely dependent on its ability to inhibit FAS-catalyzed endogenous fatty acid biogenesis, thus ruling out a significant direct effect of C75 on DNA. To determine the functional role of TP53 on breast cancer cell survival after FAS blockade, we evaluated FAS inhibitor-mediated apoptosis in MCF-7 cells transiently transfected with a pool of sequence-specific double-stranded RNA oligonucleotides targeting TP53 gene. In these conditions, TP53 protein levels were unchanged during the period of FAS-inhibitor exposure. Remarkably, siRNA-induced silencing of TP53 gene expression did result in a dramatic increase (approximately 300%) in apoptotic cell death following exposure to C75. Strikingly, there was no apparent relationship between the TP53 mutational status and sensitivity to chemical FAS inhibitor in a panel of human breast cancer cell lines. However, the degree of TP53 mRNA expression was predictive of sensitivity to C75-induced cytotoxicity, with low-TP53 mRNA expressing breast cancer cells showing hypersensitivity to FAS blockade. These findings strongly suggest that: a) TP53 is a novel molecular sensor of energy imbalance after the perturbation of endogenous fatty acid metabolism in breast cancer cells; b) TP53 function closely influences the decision between apoptosis and growth arrest following FAS blockade; and c) pharmacological inhibitors of FAS activity may be clinically useful against breast carcinomas exhibiting mutation or aberrant expression of TP53.     

家蝇抗菌肽defensin对人肝癌细胞HepG2的增殖、凋亡和周期的影响

采用四甲基偶氮噻唑蓝（MTT）比色法,分析家蝇抗菌肽defensin对人肝癌细胞HepG2体外生长增殖与凋亡的影响,用倒置光学显微镜检测defensin对人肝癌细胞HepG2和人正常心肌细胞H9C2生长增殖情况的影响,并采用流式细胞术检测defensin对人肝癌细胞HepG2细胞凋亡及细胞周期的影响。结果显示,家蝇抗菌肽defensin对人肝癌细胞HepG2的生长有抑制作用,对人正常心肌细胞H9C2无抑制作用。通过显微镜观察HepG2细胞凋亡的形态变化,MTT检测发现defensin对肿瘤细胞的增殖抑制率呈剂量反应关系和时间反应关系。defensin能诱导人肝癌细胞HepG2发生凋亡,并且影响人肝癌细胞HepG2的细胞周期。家蝇抗菌肽defensin对人肝癌细胞HepG2具有增殖抑制作用及凋亡作用,对正常人心肌细胞H9C2基本无抑制作用。     

Diallyl trisulfide selectively causes Bax- and Bak-mediated apoptosis in human lung cancer cells

Garlic-derived organosulfur compounds (OSCs) are highly effective in affording protection against chemically induced pulmonary carcinogenesis in animal models. We now demonstrate that garlic constituent diallyl trisulfide (DATS) suppresses viability of cultured human lung cancer cell lines H358 (anon-small cell lung cancer cell line) and H460 (a large cell lung cancer cell line) by causing G2-M phase cell cycle arrest and apoptotic cell death. On the other hand, a normal human bronchial epithelial cell line BEAS-2B was significantly more resistant to growth inhibition and apoptosis induction by DATS compared with lung cancer cells. We also found that even a subtle change in the OSC structure could have a significant impact on its biological activity. For example, DATS was significantly more effective than either diallyl sulfide or diallyl disulfide against proliferation of lung cancer cells. The DATS-mediated G2-M phase cell cycle arrest was explained by down-regulation of cyclin-dependent kinase 1 (Cdk1) and cell division cycle 25C protein expression leading to accumulation of Tyr15 phosphorylated (inactive) Cdk1. The DATS-induced apoptosis correlated with induction of pro-apoptotic proteins Bax, Bak and BID, and a decrease in the expression of anti-apoptotic proteins Bcl-2 and Bcl-xL in lung cancer cells but not in BEAS-2B. Knockdown of Bax and Bak proteins conferred significant protection against DATS-induced apoptotic cytoplasmic histone-associated DNA fragmentation. On the other hand, BID protein was dispensable for DATS-induced apoptosis. In conclusion, the present study indicates that Bax and Bak proteins are critical targets of DATS-induced apoptosis in human lung cancer cells.     

抗HER-2嵌合抗体chA21对SKOV3细胞增殖的抑制及诱导其凋亡的作用

目的：探讨抗HER-2嵌合抗体chA21在体外抑制高表达HER-2的人卵巢癌SKOV3细胞增殖并诱导其凋亡的作用。方法：采用MTT比色法、HE染色、透射电镜、流式细胞术及TUNEL染色法等观察和检测chA21对人卵巢癌细胞SKOV3增殖抑制和凋亡的诱导作用：结果：chA21（0．2mg／L～5．4mg／L）可显著抑制SKOV3细胞增殖并诱导其凋亡．其作用呈剂量和时间依赖性：结论：chA21在体外可显著抑制SKOV3细胞的增殖，诱导凋亡可能是其主要的作用途径，