Paris Saponin Ⅰ Induces G_2/M Cell Cycle Arrest and Apoptosis in Human Gastric Carcinoma SGC7901 Cells

The aim of this study was to investigate the effect of Paris saponin I （PSI ） on human gastric carcinoma cell growth and apoptosis and to explore the potential mechanisms. The proliferation of SGC7901 cells was monitored by the MTT cell viability assay, while the nuclear morphology of apoptotic cells was assessed by Hoechst 33258 staining. Flow cytometry was performed to analyze the cell cycle progression of propidium iodide （PI）-stained SGC7901 cells and the apoptotic rate of annexin V/PI-stained ceils. Western blotting was used to examine the expression of several cell cycle proteins, including cyclin 131 and Cdkl, and the apoptosis-regulated proteins Bcl-2, Bax, cytochrome c, procaspase-9, and procaspase-3. The MTT assay demonstrated that PSI could induce significant dose- and time-dependent inhibition of SGC7901 cell proliferation. Marked morphological changes, including condensation of chromatin, nuclear fragmentation and apoptotic bodies were clearly shown on Hoechst 33258 staining. PS I treatment also resulted in the disruption of the cell cycle at Gz/M and the induction of apoptosis. Following PSI treatment, the cell cycle-related proteins cyclin B 1 and Cdkl were down- regulated. Expression of the pro-apoptotic protein Bax was increased, while anti-apoptotic protein Bcl-2 decreased. PSI treatment resulted in elevated cytoplasmic cytochrome c and activation of the apoptotic proteases caspase-9 and caspase-3. These data indicate that PS I acts as an inhibitor of proliferation in SGC7901 cells by inducing cell cycle arrest and mitochondria-dependent apoptosis. PSI is a potential therapeutic agent against human gastric carcinoma.

Crebanine N-oxide, a natural aporphine alkaloid isolated from Stephania hainanensis, induces apoptosis and autophagy in human gastric cancer SGC-7901 cells

Objective: To investigate the cytotoxic effects and the potential mechanisms of crebanine N-oxide in SGC-7901 gastric adenocarcinoma cells. Methods: The cytotoxicity of crebanine N-oxide was evaluated by 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2-H-tetrazolium bromide assay and cellular morphology was observed under a microscope. Cell apoptosis was determined by flow cytometry using propidium iodide staining. The expression levels of apoptotic-related proteins, cleaved caspase-3, cytochrome C, p53 and Bax, and autophagyrelated proteins p62, beclin1 and LC3 were detected by Western blotting assays. Results: Crebanine N-oxide treatment significantly inhibited the proliferation of SGC-7901 cells in a dose-dependent and timedependent manner via induction of G2-phase cell cycle arrest, apoptosis, and autophagy in SGC-7901 cells.Conclusions: Crebanine N-oxide could inhibit the growth of gastric cancer cells by promoting apoptosis and autophagy and could be used as a potential agent for treating gastric cancer.

Effect of antisense human telomerase RNA on malignant behaviors of gastric carcinoma cell line SGC-7901

Objective:To studytheeffectsof antisensehumantelomeraseRNA(ahTR)transfectionon themalignantbeha-viorsof gastriccarcinomacelllineSGC-7901anditspotentialroleingenetherapyfortumor.Methods:AnantisensehTR eukaryoticexpressionvectorcontainingthesequenceof templateregionof telomererepeatswas transfectedintogastric carcinomacelllineSGC-7901withliposomeDOTAP.Theexpressionsof hTRRNAandantisensehTRRNAwereob-servedwithRT-PCR,telomeraseactivitywithPCR-ELISA.Telomerelengthwas measuredwithSouthernblot.Cellmor-phologyandcellularproliferationcapacitywerestudiedwithMTTassay.Cellcycledistributionandapoptoticstatewere observedwithflowcytometry.Efficiencyof cloneformationin softagarandtumorigencityin nudemicewereexamined andevaluatedinahTR-transfected7901cells,andplasmidpCL-neotransfected7901cellsandparental7901cellsserved as control.Results:AnantisensehTReukaryoticexpressionvectorwastransfectedinto7901cellssuccessfully.Thetelom-eraseactivityin ahTR-transfected7901cellswas decreasedfrom100%to about25%,andtelomerelengthin thecells shortenedfrom4.08kb to3.35kb at60populationdoublings(PDs).Comparedwithparental7901andpCL-neotransfect-ed7901cells,ahTR-transfected7901cellsdisplayedsomemorphologicalchanges,includingdecreasedcellatypiaandnu-cleus/cytoplasmratiounderlightmicroscope.Furthermore,ahTR-transfected7901cellsdisplayedgrowthinhibition,de-creasedinvasivecapacityin Borden’schamberinvasivemodel,increasedG 0 /G 1 phaserateandapoptoticrate,andrestored contactinhibitionanddensityinhibition.Surprisingly,ahTR-transfected7901cellslosttheircapacityof cloneformationin softagarandcarcinogensisinnudemice.Conclusion:AntisensehTRtransfectioncaninduce7901celldifferentiationand reverseitsmalignantphenotype.Thisstudyprovidesan excitingapproachfor cancertherapythroughtheinhibitionof telomeraseactivitywithantisensegeneandothertelomeraseinhibitors.

秦皮乙素对人胃癌SGC-7901细胞增殖、迁移、侵袭和糖酵解的影响

目的探讨秦皮乙素(AES)对胃癌SGC-7901细胞增殖、迁移、侵袭和糖酵解的影响及相关机制。方法采用MTT法检测细胞增殖活性;采用划痕实验和Transwell实验检测细胞迁移和侵袭能力;葡萄糖摄取量测定和乳酸含量测定实验检测细胞糖酵解情况;Western blot法检测迁移、侵袭及糖酵解相关蛋白的表达水平。结果AES能够抑制SGC-7901细胞的增殖活力,且这种抑制效果与AES的剂量成正相关。随着AES剂量的梯度增加,SGC-7901细胞的迁移、侵袭及糖酵解能力逐渐降低(P<0.05)。AES可以下调SGC-7901细胞HIF-1α、MMP-2、MMP-9、GLUT1、LDHA蛋白的表达水平(P<0.05)。结论AES对人胃癌SGC-7901细胞增殖活性及迁移、侵袭能力有抑制作用,通过抑制人胃癌SGC-7901细胞的葡萄糖摄取及乳酸生成降低糖酵解水平。AES可能通过影响缺氧诱导因子HIF-1α抑制SGC-7901细胞迁移、侵袭及有氧糖酵解过程。

Low intensity ultrasound-induced apoptosis in human gastric carcinoma cells

AIM： To investigate the low intensity ultrasound （US）- induced apoptosis in human gastric carcinoma cells and its potential mechanism and to suggest a new therapeutic approach to gastric carcinoma. METHODS： Human SGC-7901 gastric carcinoma cells were cultured in vitro and irradiated by low intensity US for 10 min at different intensities with different incubation times after irradiation. Morphologic changes were examined under microscope with trypan blue staining and then the percentage of early apoptotic cells was detected by flow cytometry （FCM） with double staining of fiuorescein isothiocyanate （FITC）- Annexin V/propidium iodide （PI）. Two-dimensional electrophoresis （2DE） was used to get the protein profile and some proteins differently expressed after US irradiation were identified by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry （MALDI-TOF-MS）. Functional analysis was performed to investigate the mechanism of US-induced cell apoptosis. RESULTS： The percentage of apoptotic cells increased about 10% after US irradiation （12.0 W/cm^2, 12 h culture）, The percentage of early apoptosis and secondary necrosis in the US-irradiated cells increased with the increased US intensity. Moreover, apoptotic cells increased with the increased culture time after US irradiation and reached its maximum at about 12 h.Several new proteins appeared after US irradiation and were up or down regulated more than 2 times. Some heat shock proteins （HSPs） were found to be associated with the signal process simulating the apoptosis of cells. CONCLUSION： Low intensity US could induce apoptosis in human gastric carcinoma cells. US-induced apoptosis is related to US intensity/culture time. US-induced apoptosis may be caspases-dependent and endoplasmic reticulum （ER） stress-triggered apoptosis may also contribute to it. Proteomic experimental system is useful in finding the protein alteration in carcinoma cells after US irradiation, helping to develop a new cancer therapy.

Expression of E-selectin, integrinβ_1 and immunoglobulin superfamily member in human gastric carcinoma cells and its clinicopathologic significance

AIM： To study the expression levels of E-selectin, integrin β1 and immunoglobulin supperfamily memberintercellular adhesion molecule-1 （ICAM-1） in human gastric carcinoma cells, and to explore the relationship between these three kinds of cell adhesion molecules and gastric carcinoma. METHODS： The serum contents of E-selectin, integrin β1 and ICAM-1 were detected by enzyme-linked immunosorbent assay （ELISA）, in 47 healthy individuals （control group） and in 57 patients with gastric carcinoma （gastric carcinoma group） respectively prior to operation and 7 d after operation. RESULTS： The serum E-selectin, ECAM-1 and integrin β1 were found to be expressed in both control and gastric carcinoma groups. However, they were highly expressed in patients with gastric carcinoma patients before operation or with unresectable tumours. The expression levels of ICAM-1 and integrin β1 were significantly higher in gastric carcinoma patients than in controls （P 〈 0.01）. A comparison of the E-selectin levels between the two groups showed statistically insignificant differnce （P = 0.64）. In addition, the expression levels were all decreased substantially in the postoperative patients subjected to radical resection of the tumours, indicating that the high level expressions of these compounds might be the important factor for predicting the prognosis of these patients. CONCLUSION： Serum E-selectin, ICAM-1 and integrin β1 expression levels are probably related to the metastasis and relapse of gastric cancer.

Growth-inhibiting and Apoptosis-inducing Effects of Tanshinone ⅡA on Human Gastric Carcinoma Cells

To explore the effects of Tanshinone Ⅱ A on the proliferation, apoptosis and gene expression of p53 and bcl-2 in human gastric carcinoma MKN-45 cells. Cell count and MTT assay were used to study the proliferation-inhibiting effect of Tanshinone Ⅱ A on MKN-45 cells. The effect of Tanshinone Ⅱ A on the cell cycle and apoptosis of MKN-45 cells were examined by propidium iodide （PI） staining and flow cytometry. Semi-quantitative RT-PCR was used to further verify the ex- pression of p53 and bcl-2 gene after exposure to Tanshinone Ⅱ A in MKN-45 cells. The results showed that Tanshinone Ⅱ A significantly inhibited the growth and proliferation of MKN-45 cells in a dose- and time-dependent manner （P〈0.05）. Tanshinone Ⅱ A arrested MKN-45 cells in G2/M phase which led to an obvious accumulation of G2/M phase cells while decreased number of Go/G1 phase cells. This resulted in apoptosis of MKN-45 cells and the apoptosis rate was as high as 43.91% after treatment with 2.0 lag/mL Tanshinone Ⅱ A for 96 h. It was also found that Tanshinone Ⅱ A up-regulated expression of p53 gene and down-regulated expression of bcl-2 gene. The cytostatic and antiproliferative effect of Tanshinone Ⅱ A makes it a promising anticancer agent for the treatment of gastric carcinoma.

The Effect of Nimesulide on the Expression of NF-κB,Bcl-2 and Bax in the Human Gastric Cancer SGC-7901 Cell Line

OBJECTIVE To investigate whether nimesulide can suppress tumor growth and induce apoptosis in SGC-7901 gastric cancer cells and to explore the molecular mechanism involved. METHODS SGC-7901 cells were cultured in RPMI 1640 medium containing different concentrations of nimesulide （0,12.5, 50, 100, 200, 400 μmol/L）. The MTT assay, morphological observation, electron microscopy （EM）, immunohistochemical analysis and Western blot analysis were employed to investigate the effects of nimesulide on the SGC-7901 cells and to explore possible related molecular mechanisms. RESULTS Nimesulide inhibited the growth of SGC-7901 cells and elicited typical apoptotic morphologic changes. Nimesulide also decreased NF-κB and Bcl-2 expression, but increased the level of the Bax protein. The positive rate of Bcl-2 protein expression at 0, 50, 100 and 200 μmol/L of nimesulide was 58.3±14.0%, 50.2±9.9%, 32.8±5.0% and 22.7±5.5% respectively based on immunohistochemical staining. The positive rate of Bax protein expression was 22.0±5.7%, 29.2±6.5%, 42.7±5.9% and 74.5±9.1% and the NF-κB expression was 74.2±10.9%, 61.8±7.6%, 36.7±10.9% and 17.5±12.3%, Significant differences were found between so μmol/L and 100 μmol/L and 200μmol/L. Western blot analysis also showed that the expression of NF-κB was decreased. CONCLUSION Nimesulide suppresses tumor growth and induces apoptosis by inhibiting NF-κB expression, which may be related to the overexpression of Bax relative to Bcl-2 expression.

DIFFERENCES IN EXPRESSION AND REGULATION BETWEEN TRANSFORMED CELLS OF THE HUMAN GASTRIC CARCINOMA ONCOGENE Ha-ras AND THE UNTRANSFORMED PARENT CELLS

An Ha-ras oncogene was isolated from a cell line of gastric carcinoma called BGE-823 in order to elucidate genetic control and the influence of DNA sequences. The oncogene was cloned and identified as a single nucleotide substitution of thymine for guanine in the 12th codon through the sequencing of its first axon. We compared the differences of expression and regulation between the transformed Ha-ras cells and untransformed parent cells. Data indicated that the expression of Ha-ras in the transformed cells was five-fold higher than in the untransformed cells and that the Ha-ras gene in the former was hypersensitive toward DNase I. In addition, a nuclear protein of 35 kilodaltons bound strongly to the 2.5 Kb fragment located upstream of the 6.6 Kb Ha-ras gene and contained a CC rich region. These results suggest that there might be another mechanism of activation for the ras gene besides point mutation.

Inhibitory effect of Fuzheng Yiliuyin in combination with chemotherapeutics on human gastric carcinoma cell strain

AIM： To study the inhibitory effects of Fuzheng Yiliuyin （Decoction for Suppressing Tumors by Strengthening the Body Resistance） in combination with chemotherapeutics on human gastric carcinoma cell strain. METHODS： Fuzheng Yiliuyin （ZY） combined with various kinds of chemotherapeutics was put into two kinds of cultivated human gastric carcinoma cell strains, then its inhibitory effects on human gastric carcinoma cell strains were determind by the MTT method. Flow cytorneter was used to assay the apoptosis rate, and the ultrastructure of gastric carcinoma cells was observed under transmission electron microscope. RESULTS： Obvious apoptosis was seen in gastric carcinoma cells after treatment with ZY for 72 h. ZY and chemical drugs had synergistic inhibition effects on the cultivated gastric carcinoma cells, but the effects were different on various cell strains. The inhibitory effects of ZY could be strengthened by cytotoxic action and apoptosis. ZY combined with tluorouracil, etoposide and cisplatin （EFP） chemotherapeutics had better inhibitory effects on SGC-7901, while ZY combined with EFP or with DDP chemotherapeutics had better inhibitory effects than other drugs on MGC-803. CONCLUSION： ZY induces apoptosis and inhibits the growth of gastric carcinoma cells. ZY has the synergistic function of chemotherapeutics.

Growth inhibitory effect of 4-phenyl butyric acid on human gastric cancer cells is associated with cell cycle arrest

AIM: To investigate the growth effects of 4-phenyl butyric acid (PBA) on human gastric carcinoma cells and their mechanisms. METHODS: Moderately-differentiated human gastric carcinoma SGC-7901 and lowly-differentiated MGC-803 cells were treated with 5, 10, 20, 40, and 60 μmol/L PBA for 1-4 d. Cell proliferation was detected using the MTT colorimetric assay. Cell cycle distributions were examined using flow cytometry.RESULTS: The proliferation of gastric carcinoma cells was inhibited by PBA in a doseand time-dependent fashion. Flow cytometry showed that SGC-7901 cells treated with low concentrations of PBA were arrested at the G0/G1 phase, whereas cells treated with high concentrations of PBA were arrested at the G2/M phase. Although MGC-803 cells treated with low concentrations of PBA were also arrested at the G0/G1 phase, cells treated with high concentrations of PBA were arrested at the S phase. CONCLUSION: The growth inhibitory effect of PBA on gastric cancer cells is associated with alteration of the cell cycle. For moderately-differentiated gastric cancer cells, the cell cycle was arrested at the G0/G1 and G2/M phases. For lowly-differentiated gastric cancer cells, the cell cycle was arrested at the G0/G1 and S phases.

INTERACTIONS BETWEEN THE HUMAN GASTRIC CARCINOMA CELL AND THE HUMAN VASCULAR ENDOTHELIAL CELL

Objective To definite the interactions between the human gastric carcinoma cell and the human vascular endothelial cell during the establishment and maintenance of the tumor vascular system and the tumor hematogenous metastasis.Methods We prepared the conditioned mediums of each cell so as to study the effect of the conditioned medium on itself or others by MTT colorimetry. The comprehensive effect of interactions between two cells was determined by stratified transfilter co culture or direct contact co culture.Results The conditioned medium of human gastric carcinoma cell can stimulate the proliferation of the human vascular endothelial cell, but the CM of HVEC can inhibit the growth of HGCC. Both kinds of cells can inhibit the growth of itself. The ultimate comprehensive effect of the interactions between two kinds of cells was increase of total cell numbers.Conclusion There exist the complicated interactions between the human gastric carcinoma cell and the human vascular endothelial cell during the tumor angiogenesis and the tumor hematogenous metastasis. The ultimate comprehensive effect of the interactions is increase of total cells numbers and tumor volume.

白术水提物通过PI3K-Akt-NF-κB通路抑制胃癌SGC-7901细胞的潜在机制

目的:探讨白术(Atractylodes macrocephala)水提物抑制胃癌SGC-7901细胞活性的潜在机制。方法:分别使用蒸馏水(对照)和白术水提物(白术治疗组)灌胃SD大鼠后,采集静脉血后分离其血清、过滤并分别命名为对照组血清(CON-S)和白术组血清(AM-S)。将胃癌SGC7901细胞分为对照组、10%AM-S组和20%AM-S组,其中两个AM-S组细胞分别在相应浓度的AM-S血清中培养24 h,对照组细胞用正常培养基培养相同时间,收取SGC7901细胞和上清液用于进一步分析。使用MTT法检测各组细胞活力,通过商业试剂盒测定乳酸脱氢酶(LDH)、丙二醛(MDA)和超氧化物歧化酶(SOD)的水平,采用ELISA试剂盒检测各组细胞中IL-6和TNF-α的含量,采用WB法评估各组细胞中PI3K-Akt-NF-κB信号通路相关蛋白的表达。结果:10%AM-S组和20%AM-S组的SGC7901胃癌细胞增殖活力相较于对照组分别降低48.9%和53.25%(P<0.05或P<0.01);胃癌细胞上清液中,相较于对照组,10%AM-S组和20%AM-S组LDH水平分别升高29.25%和123%、SOD活性分别升高18%和54.60%、MDA水平分别降低27.8%和40.0%,IL-6水平分别降低15%和17.5%、TNF-α水平分别降低29.71%和40.16%(P<0.05或P<0.01)。相较于对照组,AM-S组中PI3K-AktNF-κB信号相关蛋白的水平显著下降(P<0.05或P<0.01)。结论:白术水提物可以通过抑制癌细胞增殖活力、促进凋亡、抑制肿瘤微环境中的促炎因子分泌以及改变细胞内的氧化应激水平等方式抑制胃癌,其机制可能是通过抑制PI3K-Akt-NF-κB通路来实现这些抗癌作用的。

Inhibitory effects of dobutamine on human gastric adenocarcinoma

AIM: To explore the inhibitory effects of dobutamine on gastric adenocarcinoma cells.

苦荞异槲皮苷对人胃癌细胞SGC-7901增殖及凋亡的影响

从苦荞中提取制备异槲皮苷,研究其对人胃癌细胞SGC-7901增殖、凋亡、迁移和细胞周期的影响。将异槲皮苷作用于人胃癌SGC-7901细胞和人肾上皮细胞系293T,通过噻唑蓝法检测异槲皮苷对其增殖的影响;4’,6-二脒基-2-苯基吲哚(4’,6-diamino-2-phenyl indole,DAPI)荧光染色法观察细胞核的形态学变化;划痕擦伤迁移实验检测异槲皮苷对SGC-7901细胞迁移能力的影响;流式细胞术检测异槲皮苷对SGC-7901细胞凋亡及细胞周期的影响。结果表明:苦荞异槲皮苷可以抑制SGC-7901细胞的增殖,并呈时间和剂量依赖性,当用100μmol/L异槲皮苷作用细胞48 h后,对SGC-7901细胞的增殖抑制率达到35.92%,而对人肾上皮细胞系293T的增殖抑制率仅为3.15%;DAPI荧光染色法观察异槲皮苷处理细胞后,染色体凝聚,有凋亡小体产生;划痕擦伤实验显示,异槲皮苷能抑制SGC-7901细胞的迁移;流式细胞术检测结果表明,异槲皮苷可使G1和S期细胞减少,G2/M期细胞增多,且细胞凋亡率明显增加。综上所述,苦荞麦异槲皮苷能够诱导SGC-7901细胞发生凋亡,阻断细胞周期并抑制细胞增殖和迁移。

人参皂苷Rh2诱导人胃癌SGC-7901细胞凋亡的研究

目的研究人参皂苷Rh2(G-Rh2)对人胃癌细胞SGC-7901的影响。方法采用MTT法检测G-Rh2对SGC-7901细胞存活率的影响;流式细胞分析法检测凋亡小体的含量;免疫印迹技术及体外Caspase-3/-7活力测定方法检测Caspase的激活状态。结果G-Rh2对SGC-7901细胞生长有明显的抑制作用,且呈量-效关系,IC50为9.3μg/ml。7.5μg/mlG-Rh2作用SGC-7901细胞24h,凋亡细胞数量为6.97%。7.5μg/mlG-Rh2作用SGC-7901细胞20h,出现多聚(ADP-核糖)聚合酶[poly(ADP-ribose)polymerase,PARP]断裂,Caspase-3/-7活力开始出现,并随作用时间的延长而增强。结论G-Rh2诱导Caspase参与SGC-7901细胞凋亡。

白屈菜碱对SGC-7901细胞Cdk1、cyclinB1表达影响

研究白屈菜碱对人胃癌SGC-7901细胞Cdk1、p-Cdk1(Thr14)、cyclinB1蛋白表达,探讨白屈菜碱诱导人胃癌SGC-7901细胞G2/M期阻滞的机制.采用Western blotting法测定白屈菜碱对SGC-7901细胞Cdk1、p-Cdk1(Thr14)、cyclinB1蛋白表达的影响.不同质量浓度的白屈菜碱可显著下调人胃癌SGC-7901细胞内Cdk1与cyclinB1蛋白表达水平,同时显著上调p-Cdk1(Thr14)蛋白的表达水平,并呈一定的剂量依赖性.白屈菜碱可下调SGC-7901细胞内Cdk1和cyclinB1蛋白的表达,上调p-Cdk1(Thr14)蛋白的表达,这可能是白屈菜碱诱导SGC-7901细胞G2/M期阻滞的主要机制之一.

芫菁体内结合斑蝥素对胃癌SGC-7901细胞增殖的抑制作用

本文考察了芫菁体内结合斑蝥素和人工合成的斑蝥素盐类衍生物斑蝥素酸镁的体外抗肿瘤活性。采用WST-1法检测两者在体外对人胃腺癌SGC-7901细胞增殖的抑制作用。实验结果显示两者对SGC-7901细胞均表现出明显的抑制效果,且随药物浓度升高其抑制作用增强,呈剂量效应关系;其半数抑制浓度(IC50)分别为10.86和8.65μmol/L。此外,通过流式细胞术检测表明,结合斑蝥素能引起SGC-7901细胞G0～G1期阻滞;斑蝥素酸镁则引起SGC-7901细胞S期阻滞,两者均能通过干预SGC-7901细胞的周期来抑制其增殖。

铁线莲皂苷对人胃癌SGC-7901细胞凋亡及NF-κB表达的影响

目的:观察扬子铁线莲中提取的三萜类皂苷成分对人胃癌SGC-7901细胞株生长及凋亡的作用,研究其对核转录因子NF-κB活性的影响,初步探讨其可能的作用机制。方法:应用不同浓度铁线莲皂苷作用于SGC-7901细胞48h后,MTT法检测细胞生长抑制率;流式细胞仪Annexin V/PI双染法检测联合应用铁线莲皂苷及5-氟尿嘧啶(5-FU)后SGC-7901细胞凋亡率;应用Western blot方法检测各组胞核中NF-κBp65表达情况;酶联免疫吸附试验(ELISA)进一步确定胞核内NF-κB的活性。结果:铁线莲皂苷各浓度组对胃癌SGC-7901细胞生长抑制率均明显高于对照组(P<0.05),且随药物浓度的增加而上升。铁线莲皂苷对5-FU诱导的细胞凋亡有明显的促进作用。Western blot及ELISA法均证实铁线莲皂苷对胞核NF-κB表达及活性有一定的抑制作用,并且这种抑制作用存在着剂量依赖现象。结论:铁线莲皂苷对胃癌SGC-7901细胞具有抑制增殖、诱导凋亡的作用,其诱导细胞凋亡的机制可能与抑制胞核NF-κB表达有关。

β-紫罗兰酮诱导SGC-7901细胞凋亡作用

目的探讨β-紫罗兰酮对胃腺癌SGC-7901细胞的凋亡作用及其可能机制。方法采用细胞生长曲线、核分裂、Hoechst33258荧光染色、透射电镜和WesternBlot方法,观察了β-紫罗兰酮对SGC-7901细胞的生长抑制作用和细胞凋亡诱导情况。结果β-紫罗兰酮对SGC-7901细胞生长和有丝分裂有明显地抑制作用,EC50值为(174.93±12.79)μmol/L;并且可诱导SGC-7901细胞产生凋亡,激活Caspase-3片断和降低ERK1/2蛋白的表达,呈剂量-反应关系。结论β-紫罗兰酮可诱导SGC-7901细胞产生凋亡,不仅作用凋亡途经,而且还影响MAPK途经。