2-(3羧基-1-丙酰氨基)-2-脱氧-D-葡萄糖对人胃癌细胞系(SGC-7901)的诱导凋亡作用

目的 观察2-(3-羧基-t-丙酰氨基)-2-脱氧-D-葡萄糖(COADG)体外诱导人胃癌细胞(SGC-7901)凋亡的作用，探讨其可能作用机理。方法 采用MTT法，筛选药物作用最佳浓度。用流式细胞仪、琼脂糖凝胶电泳分析诱导凋亡前后的细胞DNA含量分析诱导凋亡前后的细胞DNA含量，透射电镜观察凋亡细胞的超微结构。结果 2-(3-羧基-1-丙酰氨基)-2-脱氧-D-葡萄糖能明显抑制胃癌细胞的增长，MTT法显示抑制程度具有时间和剂量效应关系，统计组问比较差异有显著性；流式细胞仪分析可见亚二倍体(Sub-G1)凋亡峰；电镜观察到凋亡小体。结论 2-(3-羧基-1-丙酰氨基)-2-脱氧-D-葡萄糖有诱导人胃癌细胞(SGC-7901)凋亡的作用。     

三氧化二砷诱导胃癌细胞凋亡及其对C-myc和TGF-β1表达的影响

目的 探讨三氧化二砷（As2O3）对体外培养的人胃癌细胞SGC-7901生长的抑制和诱导细胞凋亡的作用。方法 用MTT法检测药物效应，透射电镜及流式细胞仪观察As2O3处理SGC-7901细胞后细胞周期细胞凋亡。细胞免疫化学观察As2O3处理后SGC-7901细胞TGF-β1及C-myc表达的变化。结果 ①MTT法证实As2O3对SGC-7901细胞生长有抑制作用，并呈剂量．效应关系。②流式细胞仪分析As2O3处理SGC-7901细胞后细胞滞留于G2／M期，并可见凋亡峰。③透射电镜可见SGC-7901细胞出现典型的细胞凋亡及坏死形态学改变。④As2O3导致C—myc表达的波动，下调TGF-β1，表达。结论As203对人胃癌细胞SGC-7901有抑制作用，其抑制作用可能通过导致C—myc基因表达波动，诱导胃癌细胞凋亡和坏死、阻抑细胞周期进程，抑制SGC-7901细胞增殖。同时通过下调TGF-β1表达阻止胃癌的恶性进程。     

活性氧在COPADG诱导食管癌Eca-109细胞凋亡中的作用

不同浓度2-（3-羧基-1-丙酰氨基）-2-脱氧-D-葡萄糖（COPADG）作用于人食管癌Eca-109细胞24h。结果显示随COPADG浓度的升高Eca-109细胞的抑制率增加，Eca-109细胞凋亡率与COPADG浓度呈正相关，r=1．0，P〈0．01；Eca-109细胞内活性氧（ROS）水平与Eca-109细胞凋亡率呈正相关，r=1.0，P〈0．01。认为COPADG可能通过提高Eca-109细胞内ROS水平诱导Eca-109细胞凋亡。     

木黄酮对人胃癌细胞SGC-7901作用的研究

目的探讨木黄酮对体外培养的人胃癌细胞SGC-7901生长的抑制和诱导细胞凋亡的作用。方法用MTT法检测药物效应，透射电镜及流式细胞仪观察木黄酮处理SGC-7901细胞后细胞周期和细胞凋亡。细胞免疫化学观察木黄酮处理SGC-7901细胞后，SGC-7901细胞PCNA，FAS，C-mvc的变化。结果①MTT法证实木黄酮对SGC-7901细胞生长有抑制作用，并呈剂量-效应关系。②流式细胞仪分析木黄酮处理SGC-7901细胞后细胞滞留于G2／M期，并可见凋亡峰。③透射电镜可见SGC-7901细胞出现典型的细胞凋亡及坏死形态学改变。④木黄酮下调PCNA及C—myc表达，上调FAS表达。结论木黄酮对人胃癌细胞SGC-7901有抑制作用，其抑制作用可能通过下调C-mvc基因表达，上调Fas蛋白表达，下调PCNA表达，从而多途径诱导胃癌细胞凋亡和坏死、阻抑细胞周期进程，抑制SGC-7901细胞增殖。     

生存素反义寡脱氧核苷酸对人胃癌细胞株凋亡的影响

背景：生存素（survivin）是凋亡抑制蛋白（IAP）基因家族成员之一，在多数肿瘤组织中高表达。目的：观察生存素反义寡脱氧核苷酸（ASODN）对人胃癌细胞株凋亡的影响。方法：将体外培养的人胃癌细胞株SGC-7901分为不同浓度生存素ASODN组、无关寡脱氧核苷酸（N-ODN）组和对照组。以四甲基偶氮唑蓝（MTT）试验检测生存素ASODN对SGC-7901细胞生长的影响；通过形态学观察、DNA电泳和流式细胞仪分析反映细胞凋亡情况；以端粒重复序列扩增-酶联免疫吸附测定（TRAP-ELISA）方法检测端粒酶活性。结果：生存素ASODN能抑制SGC-7901细胞生长，诱导细胞凋亡，抑制端粒酶活性。凋亡细胞形态学上表现为细胞膜起泡、染色质固缩、核碎裂、凋亡小体形成；DNA电泳呈现凋亡特征性阶梯状条带；流式细胞仪分析显示G1期前出现亚二倍体凋亡峰。结论：生存素ASODN能诱导人胃癌细胞株SGC-7901凋亡，抑制细胞生长及其端粒酶活性。     

HSP90抑制剂17-DMAG对胃癌细胞株SGC-7901增殖及凋亡的影响

目的:探讨热休克蛋白90(HSP90)功能特异性抑制剂17-DMAG对胃癌细胞SGC-7901增殖及凋亡的影响.方法:体外培养人胃癌细胞SGC-7901,以不同浓度的17-DMAG处理后采用MTT法检测SGC-7901细胞的生长抑制情况,流式细胞仪碘化丙啶(PI)染色分析细胞周期分布,流式细胞仪及Annexin V-FITC试剂盒监测17-DMAG对胃癌细胞SGC-7901凋亡的影响.结果:不同浓度的17-DMAG对人胃癌细胞SGC-7901有明显的生长抑制作用,各组之间比较(P＜0.01),且呈时效量效依赖关系(F=241.313,246.856,均P＜0.001).17-DMAG作用24 h后胃癌细胞株SGC-7901呈现G2/M期阻滞,试验组与对照组比较(F=231.991,P＜0.001),呈浓度依赖关系.17-DMAG处理胃癌细胞SGC-7901 24 h早期凋亡细胞增加,48 h晚期凋亡细胞增加.结论:17-DMAG可明显抑制胃癌细胞SGC-7901的增殖,使胃癌细胞SGC-7901阻滞于G2/M期,诱导胃癌细胞SGC-7901凋亡.     

β-榄香烯对胃癌及胃癌耐药细胞杀伤作用的实验研究

目的 研究β-榄香烯联合或不联合化学治疗药物5-氟尿嘧啶(5-FU)对人胃癌细胞株SGC-7901和相应耐药细胞株SGC-7901/5-FU的杀伤作用及机制.方法 用不同剂量β-榄香烯(20、40或80μg/ml)联合或不联合5-FU (100 μg/ml)作用于SGC-7901和SGC-7901/5-FU细胞,采用四甲基偶氮唑盐实验、透射电镜观察、流式细胞仪和DNA原位末端标记(TUNEL)法检测药物对细胞的杀伤作用及其诱导细胞凋亡的情况.通过建立SGC-7901和SGC-7901/5-FU细胞裸鼠移植瘤模型观察β-榄香烯对这两种细胞的体内杀伤作用.结果 β-榄香烯在体内、外均具有抑制SCA3-7901和SGC-7901/5-FU细胞生长的作用(P值均<0.05),一定剂量范围内具量效关系(P=0.02).透射电镜、流式细胞仪和TUNEL实验均显示β-榄香烯抑制两种胃癌细胞生长的作用与其诱导细胞凋亡有关.结论 β-榄香烯在体内外对SGC-7901和SGC-7901/5-FU细胞均具杀伤作用,该作用可能与其诱导细胞凋亡有关.     

基因芯片技术分析20(S)-原人参二醇抑制人胃癌SGC-7901细胞作用机制

目的 利用基因芯片检测20(S)-原人参二醇(Ppd)作用于SGC-7901细胞后的基因表达情况,从基因水平上探讨Ppd抑制SGC-7901细胞增殖的作用机制.方法 SGC-7901细胞经不同浓度Ppd处理48 h,倒置光显微镜和荧光显微镜观察细胞形态学变化,MTT法检测SGC-7901细胞的存活率,流式细胞仪检测细胞周期变化,然后提取总RNA,逆转录生成cDNA,cDNA与基因芯片杂交,扫描仪检测杂交结果.结果 扫描信号分析数据显示10条基因表达有差异,p21、chk1 表达上调,cyclinB1、cyclinE1、E2F1、DNA 2PK、hTERT、bcl22、jnk、VEGF表达下调.结论 Ppd可以抑制SGC-9017细胞增殖,作用机制与改变细胞周期某些调控物质的基因表达、诱导细胞凋亡有关.     

曲古菌素A协同GX15-070诱导胃癌细胞SGC-7901凋亡机制的研究

目的探讨联合应用曲古菌素(Trichostatin A,TSA)和Bcl-2抑制剂GX15-070诱导人胃癌细胞SGC-7901凋亡作用及其机制。方法以联用或单用TSA、GX15-070作用于SGC-7901细胞,采用MTT法检测细胞存活率;采用Western blot法检测经处理后细胞SGC-7901中cleaved caspase 3和Bcl-2蛋白表达的变化。结果在一定浓度范围内(2.5～10μmol/L)GX15-070以浓度依赖性诱导SGC-7901细胞存活率降低,各浓度组间细胞存活率差异有统计学意义(P<0.01),且随作用时间延长,SGC-7901细胞存活率降低(P<0.05);TSA和GX15-070联用组较单用TSA组、GX15-070组SGC-7901细胞存活率差异有统计学意义(P<0.01);West-ern blot检测显示TSA能上调凋亡蛋白cleaved caspase 3的表达和下调Bcl-2蛋白的表达。结论 TSA具有协同诱导胃癌细胞SGC-7901凋亡的作用,其机制可能是通过上调cleaved caspase 3和下调Bcl-2蛋白的表达有关。     

阿司匹林对胃癌细胞株7901增殖和凋亡的影响

目的 体外观察阿司匹林（ASA）对胃癌细胞株SGC-7901细胞平殖的影响,并探讨其可能的作用机制。方法 采用噻唑蓝（MTT）法、流式细胞仪（FCM）、电镜和^3h-TdR核素标记等技术,研究ASA和SGC-7901细胞增殖的抑制和可能的机制。结果 MTT显示体外ASA对SGC-7901有细胞毒作用,与浓度和作用时间有相关性,^3H-TdR实验表明,ASA对细胞DNA合成有抑制制作。FCM显示,DNA直方图上出现典型的亚二倍体“凋亡峰”,凋亡率在7.8%-34.4%。使S期、G2/M期细胞比例升高,G1期比例下降,呈一定剂量效应关系。电镜下见典型的细胞凋亡形态学特征：细胞核染色质致密浓缩,凋亡小体形成等。结论 体外ASA对SGC-7901细胞增殖有抑制作用,可能与诱导细胞凋亡和阻止细胞周期的进展有关。     

Induction of apoptosis of human gastric carcinoma SGC-7901 cell line by 5, 7-dihydroxy-8-nitrochrysin in vitro

AIM： To investigate the effect of 5, 7-dihydroxy-8- nitrochrysin （NOChR） on apoptosis of human gastric carcinoma SGC-7901 cell line.
METHODS： SGC-7901 cells were cultured in vitro and the inhibitory effect of NOChR on proliferation of SGC-7901 cells was measured by using an Ml-r assay. NOChR-induced apoptosis rate of SGC-7901 cells was detected using flow cytometry （FCM） with PI staining. DNA ladder bands were observed by DNA agarose gel electrophoresis. The influence of NOChR on the proxisome proliferator-activated receptor-γ （PPARγ）, Bcl-2 and Bax protein expression of SGC-7901 cells was analyzed by Western blot.
RESULTS： MIF assay showed that NOChR markedly inhibited proliferation of SGC-7901 cells in a dose- dependent manner, and when ICso was 4.14 μmol/L, the potency of NOChR was 10 times than that of lead compound, chrysin （ChR, IC50 was 40.56 μmol/L）, and was similar to 5-fluorouracil （5-FU, IC50 was 4.51 μmol/L）. FCM with propidium iodide （PI） staining demonstrated that the apoptosis rates of SGC-7901 cells treated with 1.25, 5.00 and 20.00 μmol/L NOChR for 48 h were 9.8% 4- 0.2%, 36.8% 4- 1.9% and 45.5% 4- 3.5%, respectively, and were significantly higher when treated with 5.00 and 20.00 μmol/L NOChR than that with 20.00 μmol/L ChR （12.9% 4- 1.5%）. DNA agarose gel electrophoresis showed that treatment of SGC-7901 cells with 20.00 μmol/L NOChR for 48 h resulted in typical DNA ladder bands of DNA of SGC-7901 cells, which could be eliminated by treating with 10.00 μmol/L GW9662, a blocker of PPARy. Western blot analysis revealed that after 24 h of treatment with 20.00 μmol/L NOChR, PPARgamma and Bax protein expression of SGC-7901 cells increased but Bcl-2 expression decreased; however, pre-incubation with 10.00 μmol/L GW9662 could efficiently antagonize and weaken the regulatory effect of 20.00 μmol/L NOChR on Bax and Bcl-2 protein expression of SGC-7901 cells.
CONCLUSION： NOChR induces apoptosis of SGO7901 cell lines by activating PPARy and decreasing ra     

Anti-gastric cancer active immunity induced by FasL／B7-1 gene-modified tumor cells

AIM:To study the activation of cytotoxic T lymphocytes (CTLs) against gastric cancer cells induced by FasL/B7-1 (FB-11) gene-modified tumor cells,and to explore whether co-expression of FasL and B7-1 in SGC-7901 tumor cells could initiate synergistic antitumor effect. METHODS: FasL and B7-1 genes were transfected into human SGC-7901 gastric cancer cells with adenovirus vectors. The positive clones were selected by G418. FasL and B7-1 genes were detected by flow cytometry and RT-PCR. Abdominal infiltrating lymphocytes and sensitized spleen cells were obtained from mice that were immunized with SGC-7901/FB-11 or wild type SGC-7901 cells intraperitoneally,and cytotoxicity of these CTLs against tumor cells was determined by MTT assay. RESULTS: Flow cytometry and RT-PCR showed that FasL and B7-1 genes were highly expressed. FasL and B7-1 transfected cancer cells had a high apoptosis index. DNA laddering suggested that FasL and B7-1 genes induced gastric cancer cell apoptosis. FasL+/B7-1+SGC-7901 cells (SGC-7901/FB-11) were inoculated subcutaneously in the dorsal skin of C57BL/6 mice and then decreased their tumorigenicity greatly (z=2.15-46.10, P<0.01).SGC-7901/FB-11 cell-sensitized mice obtained protective immune activity against the rechallenge of wild type SGC-7901 cells (z=2.06-44.30, P<0.05). The cytotoxicity of CTLs induced by SGC-7901/FB-11 cells against SGC-7901 was significantly higher than that of CTLs activated by wild-type SGC-7901 cells (84.1±2.4% vs30.5±2.3%, P<0.05). CONCLUSION: FasL and B7-1 genes can effectively promote the activity of CTLs against gastric cancer cells. FasL/B7-1 molecules play an important role in CTL cytotoxicity.     

Effects of allicin on both telomerase activity and apoptosis in gastric cancer SGC-7901 cells

AIM: To investigate bhe effects of allicin on both telomerase activity and apoptosis in gastric cancer SGC-7901 cells.METHODS: The gastric cancer SGC-7901 adenocarcinoma cells were treated with allicin and the cell cycle, inhibitory rate, apoptosis, telomerase activity and morphoiogic changes were studied by MTT assay, flow cytometry (FCM), TRAP-PCR-ELISA assay, light microscope, electron microscope respectively. Results were compared with that of AZT (3′-Azido-3′deoxythymidine).RESULTS: SGC-7901 cells were suppressed after exposure to allicin of 0.016 mg/ml, 0.05 mg/ml, and 0.1 mg/ml for 48 h. Compared with the control, the difference was significant (P&lt;0.05). Allicin could induce apoptosis of the cells in a dose-dependent and non-linear manner and increase bhe propo~on of cells in the G2/M phase. Compared with the control, the difference was significant in terms of the percentage of cells in the G2/M phase (P&lt;0.05). Allicin could inhibit telomerase activity in a time-dependent and dose-dependent pattern. After exposure to allicin at 0.016mg/ml for 24 hours, SGC-790t cells showed typical morphologic change.CONCLUSION: Allicin can inhibit telomerase activity and induce apoptosis of gastric cancer SGC-7901 cells. Allicin may be more effective than AZT.     

RRR—α—tocopheryl succinate inhibits human gastr cancer SGC—7901 cell growth by inducing apoptos and DNA synthesis arrest

AIM: To investigate the effects of growth inhibition of human gastric cancer SGC-7901 cell with RRR-alpha-tocopheryl succinate (VES), a derivative of natural Vitamin E, via inducing apoptosis and DNA synthesis arrest. METHODS: Human gastric cancer SGC-7901 cells were regularly incubated in the presence of VES at 5, 10 and 20mg x L(-1) (VES was dissolved in absolute ethanol and diluted in RPMI 1640 complete condition media correspondingly to a final concentration of VES and 1 mL x L(-1) ethanol), succinic acid and ethanol equivalents as vehicle (VEH) control and condition media only as untreated (UT) control. Trypan blue dye exclusion analysis and MTT assay were applied to detect the cell proliferation. Cells were pulsed with 37kBq of tritiated thymidine and (3H) TdR uptake was measured to observe DNA synthesis. Apoptotic morphology was observed by electron microscopy and DAPI staining. Flow cytometry and terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) assay were performed to detect VES-triggered apoptosis.RESULTS: VES inhibited SGC-7901 cell growth in a dose-dependent manner. The growth curve showed suppression by 24.7%, 49.2% and 68.7% following 24h of VES treatment at 5, 10 and 20 mg x L(-1), respectively, similar to the findings from MTT assay. DNA synthesis was evidently reduced by 35%, 45% and 98% after 24h VES treatment at 20mg x L(-1) and 48 h at 10 and 20mg x L(-1), respectively. VES induced SGC-7901 cells to undergo apoptosis with typically apoptotic characteristics, including morphological changes of chromatin condensation, chromatin crescent formation/margination, nucleus fragmentation and apoptotic body formation, typical apoptotic sub-G1 peak by flow cytometry and increase of apoptotic cells by TUNEL assay in which 90% of cells underwent apoptosis after 48 h of VES treatment at 20 mg x L(-1). CONCLUSION: VES can inhibit human gastric cancer SGC-7901 cell growth by inducing apoptosis and DNA synthesis arrest. Inhibition of SGC-7901 cell growth by VES is dose- and time-dependent. Therefore VES can function as a potent chemotherapeutic agent against human gastric carcinogenesis.     

Tributyrin inhibits human gastric cancer SGC-7901 cell growth by inducing apoptosis and DNA synthesis arrest

AIM: To evaluate the effects of tributyrin, a pro-drug of natural butyrate and a neutral short-chain fatty acid triglyceride, on the growth inhibition of human gastric cancer SGC-7901 cell. METHODS: Human gastric cancer SGC-7901 cells were exposed to tributyrin at 0.5, 1, 2, 5, 10 and 50 mmol/L(-1) for 24-72 h. MTT assay was applied to detect the cell proliferation. [(3)H]-TdR uptake was measured to determine DNA synthesis. Apoptotic morphology was observed by electron microscopy and Hoechst-33258 staining. Flow cytometry and terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) assay were performed to detect tributyrin-triggered apoptosis. The expressions of PARP, Bcl-2 and Bax were examined by Western blot assay. RESULTS: Tributyrin could initiate growth inhibition of SGC-7901 cell in a dose- and time-dependent manner. [(3)H]-TdR uptake by SGC-7901 cells was reduced to 33.6 % after 48 h treatment with 2 mmol/L(-1) tributyrin, compared with the control (P<0.05). Apoptotic morphology was detected by TUNEL assay. Flow cytometry revealed that tributyrin could induce apoptosis of SGC-7901 cells in dose-dependent manner. After 48 hours incubation with tributyrin at 2 mmol/L(-1), the level of Bcl-2 protein was lowered, and the level of Bax protein was increased in SGC-7901, accompanied by PARP cleavage. CONCLUSION: Tributyrin could inhibit the growth of gastric cancer cells effectively in vitro by inhibiting DNA synthesis and inducing apoptosis, which was associated with the down-regulated Bcl-2 expression and the up-regulated Bax expression. Therefore, tributyrin might be a promising chemopreventive and chemotherapeutic agent against human gastric carcinogenesis.     

RRR-α-tocopheryl succinate inhibits human gastric cancer SGC-7901 cell growth by inducing apoptosis and DNA synthesis arrest

AIM: To investigate the effects of growth inhibition ofhuman gastric cancer SGC-7901 cell with RRR-α-tocopherylsuccinate (VES), a derivative of natural Vitamin E, viainducing apoptosis and DNA synthesis arrest.METHODS: Human gastric cancer SGC-7901 cells wereregularly incubated in the presence of VES at 5, 10 and20mg@ L 1(VES was dissolved in absolute ethanol anddiluted in RPMI 1640 complete condition mediacorrespondingly to a final concentration of VES and 1mL@L-1 ethanol), succinic acid and ethanol equivalents asvehicle (VEH) control andcondition media only asuntreated (UT) control. Trypan blue dye exclusionanalysis and MTT assay were applied to detect the cellproliferation. 37kBq of tritiated thymidine was added tocells and [3H] TdR uptake was measured to observe DNAsynthesis. Apoptotic morphology was observed byelectron microscopy and DAPI staining. Flow cytometryand terminal deoxynucleotidyl transferase-mediated dUTPnick end labeling (TUNEL) assay were performed to detectVES-triggered apoptosis.RESULTS: VES inhibited SGC-7901 cell growth in a dose-dependent manner. The growth curve showed suppressionby 24.7%, 49.2% and 68.7% following 24h of VEStreatment at 5, 10 and 20 mg@L 1, respectively, similar tothe findings from MTT assay. DNA synthesis wasevidently reduced by 35%, 45% and 98% after 24h VEStreatment at 20 mg@ L-1 and 48h at 10 and 20 mg@ L 1,respectively. VES induced SGC-7901 cells to undergoapoptosis with typically apoptotic characteristics,including morphological changes of chromatincondensation, chromatin crescent formation/margination,nucleus fragmentation and apoptotic body formation,typical apoptotic sub-G1 peak by flow cytometry andincrease of apoptotic cells by TUNEL assay in which 90%of cells underwent apoptosis after 48h of VES treatment at20 mcg@L-1.CONCLUSION: VES can inhibit human gastric cancer SGC-7901 cell growth by inducing apoptosis and DNA synthesisarrest. Inhibition of SGC-7901 cell growth by VES is dose-and time-dependent. Therefore VES can function as apotent chemotherapeutic agent against human gastriccarcinogenesis.     

Apoptosis of human gastric adenocarcinoma cells induced by β-ionone

AIM:To investigate the effect of β-ionone on the growth and apoptosis of gastric adenocarcinoma cell line SGC-7901.METHODS: Using M-IT, fluorescence dye (Hoechst-33258),transmission electron microscopy and the TUNEL assay,we examined growth and apoptosis of SGC-7901 cells treated with β-ionone at various concentrations (i.e. 25, 50, 100 and 200μmol/L) for 24h,48h.RESULTS:The growth of SGC-7901 cells was inhibited by β-ionone. Seven days after treatment with β-ionone at four concentrations, the inhibition rates were 12.04%, 30.59%,78.25% and 94.15%, respectively. The IC50 value of β-ionone for SGC-7901 cells was estimated to be 89μmol/L.The apoptotic morphology was demonstrated in SGC-7901 cells treated with β-ionone by Hoechst-33258 staining and electron microscopy. Apoptosis was also shown in β-iononetreated SGC-7901 cells by the TUNEL assay.CONCLUSION:β-ionone can inhibit cell proliferation and induce apoptosis of SGC-7901 cells.However, the mechanism needs to be further investigated.