小干扰RNA抑制胃癌细胞环氧合酶-2的表达

目的 观察瞬时转染环氧合酶-2特异性小干扰RNA(COX-2 siRNA)对胃癌细胞增殖与凋亡的影响,探讨COX-2在胃癌发生中的作用和RNA干扰方法 对肿瘤的治疗作用.方法 以胃癌细胞系SGC7901为研究对象,瞬时转染COX-2 siRNA,转染后72 h用RT-PCR方法 分别检测COX-2siRNA组、无意义siRNA组及空白对照组的COX-2 mRNA表达;免疫组化法与Western blot检测3组细胞的COX-2蛋白质的表达;流式细胞仪检测3组的细胞周期和凋亡情况.转染后1周内每天同一时间用噻唑蓝比色分析法(MTr)检测3组癌细胞的活力并计算癌细胞的相对生存率.结果 COX-2siRNA对胃癌细胞中COX-2 mRNA及蛋白表达均有明显抑制作用,胃癌细胞增殖受到抑制,凋亡增加,但细胞周期分布无明显变化.结论 在胃癌细胞中,COX-2表达的抑制可降低胃癌细胞的增殖速度,促进肿瘤细胞凋亡,COX-2在胃癌的发生中可能具有重要作用.     

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。     

腺病毒介导的p27kip1基因对胃癌细胞周期和DNA合成的影响

背景：近年来胃癌基因治疗的研究取得了一定的进展，但总体疗效尚不尽人意，目前正积极寻求组织特异性基因作为胃癌基因治疗的突破点。目的：以腺病毒为载体，研究p27kipl基因对胃癌细胞周期和DNA合成的影响。方法：将成功构建的携带人p27kipl基因的重组腺病毒载体Ad-p27kipl和LacZ重组腺病毒Ad-LacZ转染胃癌细胞系SGC-7901，并观察细胞形态的变化，流式细胞仪检测细胞周期和凋亡，^3H-胸腺嘧啶核苷(TdR)掺入实验测定细胞DNA合成。结果：Ad-p27kip1转染SGC-7901细胞后，细胞变圆、呈葡萄串样聚集以致脱落，G0／G1期细胞比例增加，8期、G2／M期细胞比例降低，并有凋亡发生，^3H-TdR掺入量亦显著降低。结论：腺病毒介导的p27kipl基因能使SGC-7901细胞产生G0／G1期阻滞，并能诱导细胞凋亡，抑制DNA合成，表明该基因疗法能有效抑制体外胃癌细胞的生长。     

Induction of apoptosis by arsenic trioxide and hydroxy camptothecin in gastriccancer cells in vitro

AIM To study the effects of arsenic trioxide and HCPT on different degrees of differentiated gastric cancer cells (SGC-7901, MKN-45, MKN-28)with respect to both cytotoxicity and induction of apoptosis in vitro. ~ODS The cytotoxicity of As2O3 and HCPT on gastric cancer cells was determined by MTTassay. Morphologic changes of apoptosis of gastric cancer cells were observed by light microscopy and transmission electron microscopy. Apoptosis and cell cycle changes of gastric cancer cells induced by HCPT and As2O3 were investigated by TUNEL method and flow cytometry. RESULTS As2O3 and HCPT had remarkable cytotoxic effects on different degrees of differentiated gastric cancer cells. The IC50 of As2O3 on well differentiated gastric cancer cell MKN-28, moderately differentiated gastric cancer cell SGC-7901, and poorly differentiated gastric cancer cell MKN-28 were 8. 91 μmol/L, 10. 57 μmol/L, and 11.65 μmol/L, respectively. The IC50 of HCPT on MKN-28, SGC-7901, and MKN-45 were 9. 35 rg/L, 10. 21 rg/L, and 12. 63 mg/L respectively after 48 h treatment. After 12 h of exposure to both drugs, gastric cancer cells exhibited morphologic features of apoptosis, including cell shrinkage, nuclear condensation,and formation of apoptotic bodies. A typical subdiploid peak before G0/G1 phase was observed by flow cytometry. The apoptotic rates of SGC7901, MKN-45, and MKN-28 were 13. 84%, 22.52%, and 9. 68%, respectively after 48 h exposure to 10 μmol/L As2O3. The apoptotic rates of SGC-7901, MKN-45, and MKN-28 were 21.88%, 12.35%, and 30. 26%, respectively after 48 h exposure to 10 mg/L HCPT. The apoptotic indice were 7% - 15% as assessed by TUNEL method. The effect of As2O3 on SGC-7901 showed remarkable cell cycle specificity, which induced cell death in G1 phase, and blocked G2/M phase. HCPT also showed a remarkable cell cycle specificity, by inducing cell death and apoptosis in G1 phase and arrest of proliferation at S phase. CONCLUSION AS2O3 and HCPT exhibit significant cytotoxicity on gastric cancer cells by induction of apoptosis. As2O3 and HCPT might have a promising prospect in the treatment of gastric cancer, which needs to be further studied.     

Blocking effects of genistein on cell proliferation and possible mechanism in human gastric carcinoma

AIM: To study the blocking effects of genistein on cell proliferation cycle in human gastric carcinoma cells (SGC-7901) and the possible mechanism. METHODS: MTT assay was applied in the detection of the inhibitory effects of genistein on cell proliferation. Flow cytometry was used to analyze the cell cycle distribution. Immunocytochemical technique and Western blotting were performed to detect the protein expression of cyclin D_1, cyclin B_1 and p21~(waf1/cip1). RESULTS: Genistein significantly inhibited the growth and proliferation of human gastric carcinoma cells (SGC-7901). Seven days after treatment with different concentrations of genistein (2.5, 5.0, 10.0, 20.0 μg/mL), the growth inhibitory rates were 11.2%, 28.8%, 55.3%, 84.7% respectively and cell cycles were arrested at the G(2)/ M phase. Genistein decreased cyclin D_1 protein expression and enhanced cyclin B_1 and p21~(waf1/cip1) protein expression in a concentration-dependent manner. CONCLUSION: The growth and proliferation of SGC-7901 cells can be inhibited by genistein via blocking the cell cycle, with reduced expression of cyclin D_1 and enhanced expression of cyclin B_1 and p21~(waf1/cip1) protein in the concentration range of 0-20 μg/mL.     

NS-398对人胃癌细胞株增殖及COX-2表达的影响

目的 体外观察选择性环氧化酶2(COX-2)抑制剂NS-398对人胃癌细胞株SGC7901细胞增殖及COX-2表达的影响。方法 采用噻唑蓝(MTT)法观察NS-398对SGC7901细胞增殖的影响，流式细胞仪(FCM)研究NS-398对SGC790l细胞凋亡的作用．免疫细胞化学观察COX-2蛋白的表达。结果 体外NS-398能减少SGC790l细胞株COX-2的表达．对SGC7901有细胞毒作用．可增加细胞凋亡率。结论 体外NS-398对SGC7901细胞增殖有抑制作用。可能与抑制COX-2表达及诱导细胞凋亡有关。     

Effect of NHE1 antisense gene transfection on the biological behavior of SGC-7901 human gastric carcinoma cells

AIM： To study the effect of type 1 Na^＋/H^＋ exchanger （NHE1 ） antisense human gene transfection on the biological behavior of gastric carcinoma cell line SGC-7901. METHODS： Antisense NHE1 eukaryotic expression on vector pcDNA3.1 was constructed by recombinant DNA technique and transfected into gastric carcinoma cell line SGC-7901 with DOTAP liposome transfection method. Morphological changes of cells were observed with optic and electron microscopes. Changes in cell proliferative capacity, apoptosis, intracellular pH （pHi）, cell cycle, clone formation in two-layer soft agar, and tumorigenicity in nude mice were examined. RESULTS： Antisense eukaryotic expressing vectors were successfully constructed and transfected into SGC-7901. The transfectant obtained named 7901 -antisense （7901-AS） stablely produced antisense NHE1. There was a significant difference between the pHi of 7901-AS cells （6.77 ± 0.05） and that of 7901-zeo cells and SGC-7901 cells （7.24 ± 0.03 and 7.26 ± 0.03, P 〈 0.01）. Compared with SGC-7901 and 7901-zeo cells, 7901-AS cells mostly showed cell proliferation inhibition, G1/G0 phase arrest, increased cell apoptotic rate, recovery of contact inhibition, and density contact. The tumorigenicity in nude mice and cloning efficiency in the two-layer soft agar were clearly inhibited. CONCLUSION： NHE1 antisense gene significantly restrains the malignant behavior of human gastric carcinoma cells, suppresses cell growth and induces cell apoptosis, and partially reverses the malignant phenotypes of SGC-7901 . These results suggest a potential role for human tumor gene therapy.     

吲哚美辛对胃癌SGC 7901细胞增殖及Cyclin D1蛋白表达的影响

目的:观察引哚美辛对胃癌SGC 7901细胞增殖及细胞周期调控蛋白Cyclin D1表达的影响,探讨吲哚美辛抑制细胞增殖的机制.方法:采用MTT法观察吲哚美辛对胃癌细胞SGC 7901增殖的影响,采用流式细胞仪观察细胞周期分布的变化,采用免疫细胞化学方法检测Cyclin D1蛋白的表达.结果:吲哚美辛呈时间、浓度依赖方式抑制胃癌SGC 7901细胞增殖,改变细胞周期的分布,增加G0/G1期细胞的比例,下调Cyclin D1蛋白的表达.结论:吲哚美辛可能通过下调Cyclin D1蛋白表达,影响细胞周期的分布来抑制胃癌SGC7901细胞增殖.     

核抗原Mina53在人胃癌细胞中的作用及其意义探讨

背景:核抗原Mina53基因为原癌基因Myc的下游直接靶基因之一,在一些消化系统恶性肿瘤中呈高表达,并与肿瘤增殖、侵袭、转移或患者生存期相关。目的:研究Mina53在人胃癌细胞中的作用及其对胃癌发生、发展的意义。方法:选择Mina53表达水平较高的人胃癌细胞株SGC7901和AGS,应用RNA干扰技术下调其Mina53表达,以转染无关序列siRNA的细胞作为对照组。采用CCK-8实验检测细胞增殖,流式细胞术检测细胞周期和细胞凋亡,细胞侵袭和迁移实验检测细胞侵袭、迁移能力。结果:与相应对照组相比,Mina53 siRNA转染组SGC7901、AGS细胞增殖受抑(96 h相对增殖率:60%和68%),并发生明显细胞周期G1期阻滞(SGC7901细胞G1/G2:2.76±0.12对1.86±0.06,P<0.05;AGS细胞G1/G2:1.78±0.13对1.34±0.05,P<0.05),细胞凋亡率分别增加9.8%±1.2%和10.6%±1.5%(P<0.05),穿透Transwell小室基质胶细胞数(SGC7901细胞:11.67±0.88对24.33±1.45,P<0.05;AGS细胞:8.00±1.15对20.33±1.73,P<0.05)和穿透Transwell小室微孔膜细胞数(SGC7901细胞:7.00±1.53对14.67±2.03,P<0.05;AGS细胞:8.00±1.16对15.33±1.45,P<0.05)均显著减少。结论:Mina53对人胃癌细胞的增殖、细胞周期、细胞凋亡以及侵袭、迁移能力具有调控作用,可能影响胃癌的生长、浸润和转移,有望作为胃癌基因治疗的靶点。     

胃肠富集Krüppel样因子基因转染对人胃癌细胞株SGC-7901及裸鼠移植瘤生长的影响

目的 探讨外源性胃肠富集Krüppel样因子(GKLF)基因转染对人胃癌细胞株SGC-7901在体内外的抗肿瘤效应.方法 荧光实时定量PCR和Western印迹法检测GKLF基因转染前后人胃癌细胞株SGC-7901中GKLF mRNA和蛋白的表达.应用四甲基偶氮唑盐(MTT)法、流式细胞技术、克隆形成实验和细胞侵袭实验分别检测GKLF基因转染后SGC-7901细胞增殖和侵袭力的变化.观察裸鼠移植瘤生长情况和应用免疫组织化学法检测移植瘤组织中微血管密度(MVD).结果 GKLF基因转染后,SGC7901-pcDNA3.1-GKLF组中GKLF mRNA(0.1216±0.0061)和蛋白(1.0547±0.0172)的表达明显高于SGC-7901组[分别为(0.0029±0.0012)和(0.6240±0.0177)]和SGC7901-pcDNA3.1组[分别为(0.0037±0.0013)和(0.5627±0.0510)],P＜0.05.与SGC-7901组和SGC7901-pcDNA 3.1组相比,从48 h开始,SGC7901-pcDNA 3.1-GKLF组细胞生长速度减慢、细胞出现G0/G1期部分阻滞、克隆形成率低、细胞侵袭力明显减弱(P值均＜0.05).SGC7901-pcDNA3.1-GKLF组皮下移植瘤生长速度减慢、瘤重轻、MVD低(P值均＜0.05).结论 GKLF基因转染可导致人胃癌细胞株SGC-7901的增殖活性和侵袭力降低,抑制裸鼠移植瘤生长和血管生成.

Abstract：

Objective To investigate the antitumour effects of transfected gut-enriched Krüppellike factor(GKLF) on human gastric carcinoma cell line SGC-7901 in vitro and in vivo. Methods The expression of GKLF mRNA and protein in human gastric carcinoma cell line SGC-7901 were detected before and after transfection by real-time fluorescence quantitative PCR and Western blot,respectively. Proliferation and invasion in SGC-7901 were measured respectively by MTT assay, flow cytometry, colony formation assay and cell invasion assay after transfected with GKLF. The growth of xenograft was observed, the microvessel density(MVD) of xenograft tissue was determined by immunohistochemistry. Results The GKLF mRNA and protein in SGC-7901 were overexpressed after transfected with GKLF(P＜0.05). The proliferative speed of SGC7901-pcDNA3.1-GKLF group was markedly lower than that of SGC-7901 and SGC7901-pcDNA3.1 groups (P＜0.05). Transfected with GKLF caused part of the G0/G1 arrest, decreased clone formation rate and the invasion ability (P＜0.05). The growth speed of xenograft in SGC7901-pcDNA3.1-GKLF group was lower, the weight and MVD of xenograft tissue in SGC7901-pcDNA3. 1-GKLF group were less (P＜ 0. 05).Conclusion Transfected with GKLF maysuppress proliferation and invasion in human gastric carcinoma cell line SGC-7901, inhibit the growth and the angiogenesis of xenograft in nude mice.     

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.     

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 24-72 h. MTT assay was applied to detect the cell proliferation.[3H]-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 SGC7901 cell in a dose- and time-dependent manner. [3H]-TdR uptake by SGC-7901 cells was reduced to 33.6% after 48 h 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 downregulated Bcl-2 expression and the up-regulated Bax expression. Therefore, tributyrin might be a promising chemopreventive and chemotherapeutic agent against human gastric carcinogenesis.     

AG490对胃癌细胞株SGC-7901细胞周期、凋亡和STAT3表达的影响

背景：JAK2酪氨酸激酶特异性抑制剂AG490可抑制胃癌细胞生长,但目前对其作用机制还知之甚少。目的：探讨AG490对胃癌细胞株SGC-7901细胞周期、凋亡和STAT3 mRNA表达的影响。方法：以不同浓度AG490处理胃癌细胞株SGC-7901,流式细胞术检测细胞周期和凋亡情况,RT-PCR法检测STAT3 mRNA表达。结果：胃癌细胞株SGC-7901经AG490作用48 h后,100μmol/L组的S期、G2/M期细胞比例显著增加（P〈0.01）,1μmol/L组和10μmol/L组仅G2/M期细胞比例显著下降（P〈0.05）。AG490作用48h后,各浓度组的细胞凋亡率均显著增加（P〈0.01）。AG490作用24 h和48 h后,各浓度组的STAT3 mRNA表达均无明显变化（P〉0.05）。结论：AG490可影响胃癌细胞株SGC-7901的细胞周期并诱导细胞凋亡,但不影响STAT3 mRNA的表达。     

曲古菌素A对人胃癌细胞增殖和细胞周期的作用

目的 观察曲古菌素A(TSA)对人胃癌细胞株SGC-7901细胞增殖及细胞周期的影响,探讨其可能的机制.方法 TSA干预人胃癌SGC-7901细胞24 h后.采用四甲基偶氮唑盐法检测其对细胞增殖的影响,流式细胞技术检测细胞周期,实时PCR检测细胞周期素D1和p21 mRNA的表达情况.结果 经TSA干预24 h后,人胃癌SGC-7901细胞增殖受抑制,TSA 0.1、0.5和2.0μmol/L组抑制率分别为3.52%±6.11%、13.29%±4.13%和14.24%±2.80%;同时TSA 0.5μmol/L组(71.26%±0.51%)和TSA 2.0μmol/L组(71.03%±0.12%)的G0/Gl期细胞比例明显高于对照组(51.12%±1.17%);TSA 0.5μmol/L组(13.55%±0.44%)和TSA 2.0 μmol/L组(10.63%±0.63%)的S期细胞比例明显低于对照组(34.60%±0.60%).出现G0/G1细胞周期阻滞.TSA干预后细胞周期相关基因细胞周期素D1 mRNA表达下调和p21 mRNA表达上调.结论 TSA通过调控细胞周期相关基因细胞周期素D1和p21的表达,抑制人胃癌SGC-7901细胞的增殖,引起G0/G1期细胞周期阻滞,最终影响肿瘤细胞的生长.     

Heat shock protein 70 antisense oligonucleotide inhibits cell growth and induces apoptosis in human gastric cancer cell line SGC-7901

AIM: Heat shock protein (HSP)70 is over-expressed in human gastric cancer and plays an important role in the progression of this cancer. We investigated the effects of antisense HSP70 oligomer on human gastric cancer cell line SGC-7901, and its potential role in gene therapy for this cancer. METHODS: Human gastric cancer cell line SGC-7901 was treated in vitro with various concentrations of antisense HSP70 oligonucleotides at different intervals. Growth inhibition was determined as percentage by trypan blue dye exclusion test. Extracted DNA was electrophoresed on agarose gel, and distribution of cell cycle and kinetics of apoptosis induction were analyzed by propidium iodide DNA incorporation using flow cytometry, which was also used to detect the effects of antisense oligomer pretreatment on the subsequent apoptosis induced by heat shock in SGC-7901 cells. Proteins were extracted for simultaneous measurement of HSP70 expression level by SDS-PAGE Western blotting. RESULTS: The number of viable cells decreased in a dose-and time-dependent manner, and ladder-like patterns of DNA fragments were observed in SGC-7901 cells treated with antisense HSP70 oligomers at a concentration of 10μmol/L for 48 h or 8μmol/L for 72 h, which were consistent with inter-nucleosomal DNA fragmentation. Flow cytometric analysis showed a dose- and time-dependent increase in apoptotic rate by HSP70 antisense oligomers. This response was accompanied with a decrease in the percentage of cells in the G_1 and S phases of the cell cycle, suggesting inhibition of cell proliferation. In addition, flow cytometry also showed that pretreatment of SGC-7901 cells with HSP70 antisense oligomers enhanced the subsequent apoptosis induced by heat shock treatment. Western blotting demonstrated that HSP70 antisense oligomers inhibited HSP70 expression, which preceded apoptosis, and HSP70 was undetectable at the concentration of 10 μmol/L for 48 h or 8 μmol/L for 72 h. CONCLUSION: Antisense HSP70 oligomers can abrogate HSP70 expression in SGC-7901 cells, which may in turn induce apoptosis and inhibit cell proliferation, conversely suggesting that HSP70 is required for the proliferation and survival of human gastric cancer cells under normal conditions.     

miR-449a Regulates Proliferation and Chemosensitivity to Cisplatin by Targeting Cyclin D1 and BCL2 in SGC7901 Cells

Background

Recently, several miRNAs have been determined as tumor suppressors in various cancers, such as microRNA-449a. However, the exact molecular mechanisms underlying miR-449a regulated cell proliferation and chemosensitivity in gastric cancer cells have not been well documented.

Aim

The present study was designed to test whether miR-449a mediates cell proliferation and chemosensitivity in gastric cancer cells via regulating cyclin D1 and BCL2.

Methods

In vitro, the ability of cell proliferation and cell viability were measured by MTT assay; cell cycle and cell apoptosis was detected by FCM. qRT-PCR was used to measure the expression of miR-449a. Western blot and real-time PCR assays were used to detect the expression of cyclin D1 and BCL2 in gastric cancer cell line SGC7901.

Results

miR-449a expression was downregulated in gastric cancer cell line SGC7901 and human gastric cancer tissues, compared to the gastric epithelial cell line GES-1 and matched non-tumor associated tissues. Upregulation of miR-449a reduced the proliferation of SGC7901 cells. Ectopic expression of miR-449a decreased the percentage of S phase cells, increased the percentage of G1/G0 phase cells and increased the apoptosis induced by cisplatin. Moreover, miR-449a inhibited SGC7901 cells proliferation and enhanced cisplatin chemosensitivity by downregulating expression of BCL2 and cyclin D1, respectively, via directly targeting the 3′-untranslated regions of BCL2 and cyclin D1 mRNA.

Conclusions

This is the first report to provide evidence that miR-449a could modulate cell cycle and apoptosis through regulating cyclin D1 and BCL2 expression in SGC7901 cells.     

人端粒保护蛋白反义核酸抑制SGC7901胃癌细胞增殖

目的 研究人端粒保护蛋白（human protection of telomeres,hPOT1）对胃癌细胞生长增殖的作用.方法 利用本课题组先前所构建的hPOT1正、反义核酸真核表达载体,转染SGC7901胃癌细胞,G418筛选阳性克隆,用Western印迹法、MTT法、流式细胞仪、透射电镜等技术观察基因转染后SGC7901细胞hPOT1蛋白的表达、细胞生长曲线、细胞周期、细胞凋亡及细胞形态学的变化.结果 转染了hPOT1反义核酸真核表达载体（pcDNA-as-hPOT1）的SGC7901胃癌细胞hPOT1表达降低,生长减慢,阻滞于G2/M期,细胞凋亡增加.结论hPOT1反义核酸真核表达载体能显著抑制hPOT1蛋白的表达,hPOT1蛋白可能参与胃癌细胞的周期调控,并与细胞的生长增殖有关.     

槲皮素对胃癌细胞SGC-7901和BGG-823生长的影响

目的 观察槲皮素对胃癌细胞SGC-7901和BGC-823生长和增殖的影响。方法 以台盼蓝拒染法计数胃癌细胞的生长抑制率，荧光显微镜了解凋亡的发生，流式细胞术检测细胞周期变化。结果 台盼蓝拒染法计数显示槲皮素抑制SGC-7901和BGC-823细胞增殖的作用明显，呈浓度和时问依赖性，槲皮素处理48h后的Ic50为14．12μm(SGC-7901)和28．13μm(BGC-823)。形态学检测显示出细胞凋亡的特征变化，流式细胞仪检测表明经10～20μm／L的槲皮素处理，SGC-7901细胞周期阻滞于G0／G1期，BGC-823细胞周期阻滞于S期。结论 槲皮素能抑制胃癌细胞的生长并诱导其发生凋亡，是有效的抗癌药。