褪黑素对胰腺癌细胞株SW1990体外增殖及凋亡的影响

目的 探讨褪黑素(MT)体外抑制胰腺癌细胞株SW1990增殖及诱导其凋亡的作用.方法 以不同浓度的MT(0.1、0.5、1.0、2.5及5.0 mmol/L)处理体外培养的胰腺癌细胞株SW1990细胞24、48、72 h.用MTT法测定细胞增殖,以Annexin V/PI检测细胞凋亡,流式细胞仪分析细胞周期及Western blotting检测细胞Bcl-2、Bax蛋白表达.结果 MT呈浓度和时间依赖性抑制SW1990细胞的增殖.0.1～5.0 mmol/L MT作用48 h后,细胞的增殖抑制率为7.4%～85.8%.1.0～5.0 mmoL/L MT作用48 h后,G0/G1期比例为72.6%～85.3%,细胞凋亡率为21.5%～41.7%,同时Bcl-2蛋白表达下调,Bcl-2/Bax比值下降.结论 MT可以抑制SW1990细胞增殖,其机制可能与上调Bax表达,下调Bcl-2表达,促进细胞凋亡,将细胞周期阻止于G0/G1期有关.     

沙利度胺对人胰腺癌细胞株SW1990体外增殖及凋亡的影响

目的 观察沙利度胺(THD)体外抑制人胰腺癌细胞株SW1990增殖及诱导其凋亡的作用.方法 应用不同浓度的THD(3.125、6.25、12.5、25、50、100、200、400μg/ml)处理胰腺癌SW1990细胞24、48、72 h,用MTT法测定细胞的生长抑制率,流式细胞仪分析细胞周期,Annexin V/PI检测细胞凋亡率,蛋白质印迹法检测细胞Bcl-2、Bax蛋白的表达.结果 THD呈浓度和时间依赖性抑制胰腺癌细胞SW1990的生长.200μg/ml的THD干预使SW1990细胞G0/G1期比例从(41.15±2.23)％上升到(58.83 ±2.33)％;细胞凋亡率从2.6％增加到28.0％;细胞Bax蛋白表达量从0.17±0.03上调到0.33±0.04,Bcl-2蛋白表达量从0.35±0.02下调到0.17±0.01,Bcl-2/Bax比值从2.17±0.44下降到0.52±0.07.结论 THD可以抑制SW1990细胞增殖,其机制可能与上调Bax蛋白表达、下调Bcl-2蛋白表达,促进细胞凋亡,将细胞周期阻滞于G0/G1期有关.     

Antitumor bioactivity of adenovirus-mediated p27mt in colorectal cancer cell line SW480

AIM： To explore the antitumor bioactivity of adenovirusmediated mutant type p27^kip1 gene in a colorectal cancer cell line SW480. METHODS： We constructed recombinant adenovirus vector expressing a mutant type p27^kip1 gene （ad- p27mt）, with mutation of Thr-187/Pro-188 （ACGCCC） to Met-187/Ile-188 （ATGATC）, and transduced into SW480 cells. Then we detected expression of p27, Bcl-2 and Bax protein in the transductants by Western blotting, cell cycle of transductants by a digital flow cytometric system, migrating potential with Boyden Chamber and SW480 tumor cell growth inhibition in vitro and in vivo. RESULTS： We found that a recombinant adenovirus vector of expressing ad-p27mt, with mutation of Thr-187/Pro-188 （ACGCCC） to Met-187/Ile-188 （ATGATC） has potent inhibition of SW480 tumor cell growth in vitro and in vivo. Furthermore, ad-p27mt induced cell apoptosis via regulating bax and bcl-2 expressions, and G1/S arrest in SW480 cells and inhibited cell migration. CONCLUSION： ad-p27mt has a strong anti-tumor bioactivity and has the potential to develop into new therapeutic agents for colorectal cancer.     

Chitooligosaccharides promote radiosensitivity in colon cancer line SW480

AIM: To investigate the anti-proliferation and radiosensitization effect of chitooligosaccharides(COS) on human colon cancer cell line SW480.METHODS: SW480 cells were treated with 0, 1.0, 2.0, 3.0, 4.0 and 5.0 mg/m L of COS for 48 h. CCK-8 assay was employed to obtain the cell survival ratio of SW480 cells, and the anti-proliferation curve was observed with the inhibition ratio of COS on SW480 cells. The RAY + COS group was treated with 1.0 mg/m L of COS for 48 h, while both the RAY and RAY+COS groups were exposed to X-ray at 0, 1, 2, 4, 6 and 8 Gy, respectively. Clonogenic assay was used to analyze cell viability in the two groups at 10 d after treatment, and a cell survival curve was used to analyze the sensitization ratio of COS. The RAY group was exposed to X-ray at 6 Gy, while the RAY+COS group was treated with 1.0 mg/m L of COS for 48 h in advance and exposed to X-ray at 6 Gy. Flow cytometry was employed to detect cell cycle and apoptosis rate in the non-treatment group, as well as in the RAY and RAY + COS groups after 24 h of treatment.RESULTS: COS inhibited the proliferation of SW480 cells, and the inhibition rate positively correlated with the concentration of COS(P 0.01). Cell viability decreased as radiation dose increased in the RAY and RAY+COS groups(P 0.01). Cell viabilities in the RAY+COS group were lower than in the RAY group at all doses of X-ray exposure(P 0.01), and the sensitization ratio of COS on SW480 cells was 1.39. Compared with the non-treatment group, there was a significant increase in apoptosis rate in both the RAYand RAY + COS groups; while the apoptosis rate in the RAY+COS group was significantly higher than in the RAY group(P 0.01). In comparing these three groups, the percentage of G2/M phase in both the RAY and RAY + COS groups significantly increased, and the percentage of the S phase and G0/G1 phase was downregulated. Furthermore, the percentage in the G2/M phase was higher, and the percentage in the S phase and G0/G1 phase was lower in the RAY + COS group vs RAY group(P 0.01). CONCLUSION: COS can inhibit the proliferation of SW480 cells and enhance the radiosensitization of SW480 cells, inducing apoptosis and G2/M phase arrest.     

雌激素受体β过表达对大肠癌细胞增殖凋亡的影响

目的观察雌激素受体β（ERβ）过表达对大肠癌细胞增殖和凋亡的影响,并探讨其机制。方法以脂质体介导的ERβ基因转染SW480细胞,G418筛选阳性克隆（SW480-C1-ERβ）。RT—PCR及WesternBlot鉴定ERβ的过表达。以正常SW480细胞和转染了空质粒的SW480细胞（SW480-pEGFP—C1）作为对照,在无雌激素或有雌激素作用的条件下,采用MTT法检测细胞增殖,流式细胞术检测细胞凋亡率,实时荧光定量RT—PCR方法检测凋亡相关基因survivin和Bax表达。结果SW480和SW480-pEGFP—C1细胞中ERβ mRNA和蛋白表达较低,而稳定转染的SW480-C1-ERβ细胞中ERβmRNA和蛋白表达明显增加。在有或无雌激素作用的条件下均可发现,与SW480细胞或SW480-pEGFP—C1细胞比较,SW480-C1-ERβ细胞增殖速度减慢,凋亡率明显增高,survivin表达减低,Bax表达增高;在SW480-C1-ERβ细胞中,有雌激素作用者较无雌激素作用者以上变化更明显。结论ERβ过表达可以同时以配体非依赖性和配体依赖性的方式抑制细胞增殖和增加细胞凋亡,可能与调控凋亡相关基因survivin和Bax表达有关。     

吡格列酮对成骨细胞Bax、Bcl-2蛋白表达的影响

目的 研究吡格列酮对成骨细胞增殖及凋亡的影响,并进一步了解其凋亡发生机制.方法 以MC3T3-E1成骨细胞株为实验对象,分别用0、5、10、20、30、40 μmol/L吡格列酮干预,观察细胞活性、细胞周期及凋亡率的变化,同时检测细胞Bcl-2,Bax蛋白表达.结果 随着浓度增加,成骨细胞的活性逐渐降低;与对照组相比,G0/G1,G2/M期细胞增多,S期细胞明显减少;凋亡率在5、10 μmol/L时低于对照组,30、40 μmol/L较对照组显著增高;Bax表达在10 μmol/L时明显减弱,20 μmol/L时回复到正常,30、40μmol/L较对照组显著增强;Bcl-2表达在浓度≤20 μmol/L时显著增强;对于Bax/Bcl-2相对表达强度与细胞凋亡率做相关性分析,两者呈显著性正相关(n=15,r=0.796,P＜0.01).结论 吡格列酮在低浓度抑制成骨细胞凋亡,对细胞起保护作用,较高浓度则促进细胞凋亡,Bax/Bcl-2参与其凋亡机制,并可能起关键调控作用.吡格列酮抑制成骨细胞DNA合成,抑制细胞增殖,导致细胞活性下降.

Abstract：

Objective To investigate the effects of pioglitazone on osteoblast proliferation and apoptosis.Methods MC3T3-E1 mouse osteoblastic cells were treated with 0, 5, 10, 20, 30, and 40 μmol/L pioglitazone for 24 h. Cell viability was measured by MTT, cell cycle and apoptosis were inspected with flow cytometry, the expressions of Bcl-2 and Bax proteins were examined via immuno-chemical staining. Results Survival of osteoblasts decreased in a dose-dependent manner. Compared with the control group, the cells in the G0/G1 and G2/M stages increased, while the cells in S stage decreased significantly. The percentage of apoptosis at 5 and 10 μmol/L were lower than that of the control group(P ＜ 0.05), While it was increased significantly at 30 and 40 μmol/L(P ＜0.01). Bax expression was attenuated at 10 μmol/L(P＜0. 01), returned to normal by 20 μmol/L, and was increased by 30 and 40 μmol/L(P ＜ 0. 01). Bcl-2 expression was enhanced at the dose ≤ 20 μmol/L(P ＜0.01). Positive correlation was found between the death rate and the expression intensity of Bax/Bcl-2(n = 15, r=0.796, P＜0.01). Conclusions Pioglitazone inhibits apoptosis of osteoblasts at low concentrations and protects the cells, but promotes their apoptosis at higher concentration, Bax/Bcl-2 may play an important role in mediating the piglitazone-induced apoptosis of osteoblasts. It inhibits DNA synthesis and cell proliferation.     

肿瘤坏死因子相关配体与阿司匹林合用对肝癌SMMC-7721细胞凋亡的影响

目的 观察肿瘤坏死因子相关的凋亡诱导配体(TRAIL)与阿司匹林合用对肝癌SMMC-772l细胞的作用。方法 氨甲喋呤法检测SMMC-772l细胞存活分数；流式细胞仪检测SMMC-772l细胞的凋亡率和细胞周期；WesternBlot法检测凋亡相关基因的表达。结果 单用300ng／ml TRAIL、3、10mmol／L阿司匹林SMMC-772l细胞存活分数分别为82．76％、81．34％和71．29％，合用的存活分数分别为43．5％、37．8％。3、l0mmol／L阿司匹林与300ng／ml TRAIL合用诱导的细胞凋亡率明显大于单用两药诱导的细胞凋亡率之和(单用300ng／ml TRAIL、3mmol／L和10mmol／L阿司匹林凋亡率分别为21．25％、1．89％和6．08％，合用的凋亡率分别34．76％，38．56％)并使G0/Gl期细胞增加l3、10mmol／L的阿司匹林使SMMC-772l细胞Bcl-2的表达明显减弱，但对Bax的表达无影响。结论 TRAlL与阿司匹林合用对肝癌SMMC-772l细胞有明显的协同杀伤作用，其机制可能与阿司匹林抑制Bcl-2的表达有关。     

硼替佐米对胰腺癌细胞BxPC3、SW1990生长抑制作用的体外研究

目的 观察硼替佐米对胰腺癌细胞BxPC3、SW1990增殖、凋亡的影响,探讨硼替佐米杀伤癌细胞的可能机制.方法 应用1、10、50、100、500 nmol/L及1、10 μmol/L的硼替佐米干预BxPC3、SW1990细胞,以硼替佐米未干预的细胞作为对照组.采用四甲基偶氮唑蓝（MTT）法检测细胞的增殖;流式细胞仪检测细胞凋亡;RT-PCR法检测Bak、Bax、Bcl-2、Bcl-xl、survivin mRNA表达;蛋白质印迹法检测pro-caspase-3、cleaved-caspase-3、Bax、Bcl-2、surviving蛋白表达.结果 大于50 nmol/L的硼替佐米干预胰腺癌BxPC3、SW1990细胞时,呈浓度及时间依赖性抑制细胞的增殖,其中硼替佐米对BxPC3细胞的生长抑制作用显著大于对SW1990细胞的作用,两者差异有统计学意义（P值均＜0.05）.100 nmol/L硼替佐米干预组BxPC3和SW1990细胞凋亡率分别为（22.56±4.23）％和（（12.71±2.23）％,显著高于对照组的（2.15±0.47）％和（2.32±0.54）％（P值均＜0.05）,且BxPC3细胞的凋亡率显著高于SW1990细胞（P＜0.05）.100 nmol/L硼替佐米干预48 h后BxPC3和SW1990细胞的Bak mRNA表达无显著变化,Bax mRNA及蛋白表达显著增加（P值均＜0.05）,Bcl-2 mRNA和蛋白表达及Bcl-xl mRNA表达均减少（P值均＜0.05）.survivin mRNA和蛋白表达在BxPC3细胞中均减少,而在SW1990细胞中均增加（P值均＜0.05）.2株细胞的pro-caspase-3蛋白表达减少,而cleaved-caspase-3蛋白表达增加（P值均＜0.05）.结论 硼替佐米可抑制胰腺癌细胞BxPC3、SW1990的增殖、诱导凋亡,对BxPC3细胞的作用高于对SW1990细胞,其机制可能与激活线粒体内源性凋亡途径及survivin参与的肿瘤耐药相关.     

Cd Se/Zn S quantum dots induce photodynamic effects and cytotoxicity in pancreatic cancer cells

AIM: To investigate the photodynamic effect of Cd Se/Zn S quantum dots(QDs) on pancreatic cancer cells and elucidate the probable mechanisms.METHODS: The pancreatic cancer cell line SW1990 was treated with different concentrations of Cd Se/Zn S QDs(0, 0.5, 1.0, 1.5, 2.0, 2.5 μmol/L), with or without illumination. The viability of SW1990 cells was tested using the Cell Counting Kit-8(CCK-8) assay. The ultrastructural changes of SW1990 cells were observed by transmission electron microscopy. Apoptosis was detected by nuclear staining and flow cytometry(FCM). Reactive oxygen species(ROS) were measured by dichlorofluorescein diacetate via fluorescence microscopy. Expression of Bax, Bcl-2 and caspase-3 was measured by real-time polymerase chain reaction(PCR) and protein immunoblotting 24 h after SW1990 cells were treated with Cd Se/Zn S QDs and illuminated.RESULTS: The CCK-8 assay results showed that both Cd Se/Zn S QDs with and without illumination suppressed SW1990 cell proliferation. Cell viability was significantly lower when illuminated or with a longer incubation time and a higher light dose. Cd Se/Zn S QDs with illumination caused ultrastructural changes in SW1990 cells, such as organelle degeneration and chromatin condensation and aggregation at the periphery of the nucleus. Fluorescence microscopy and FCM showed that Cd Se/Zn S QDs(1.5 μmol/L) with illumination increased SW1990 cell apoptosis(53.2%) and ROS generation compared with no illumination. Real-time PCR showed that expression of Bax and caspase-3 was upregulated and Bcl-2 was downregulated. Immunoblotting results were consistent with real-time PCR results. Inhibition of ROS and apoptosis both attenuated QD-photodynamictherapy-induced cell death.CONCLUSION: Cd Se/Zn S QDs can be used as a photosensitizer to inhibit SW1990 cell proliferation through ROS generation and apoptotic protein expression regulation.     

斑蝥素诱导人胰腺癌细胞凋亡的实验研究

目的 探讨斑蝥素（Cantharidin）对人胰腺癌细胞凋亡的影响及其作用机制。方法采用MTT法观察斑蝥素对人胰腺癌细胞株SW1990细胞增殖的抑制作用。采用Hoechst33258染色、TUNNEL染色、流式细胞术检测细胞凋亡改变，并以RT—PCR和Westernblot检测凋亡调节基因p53和Bcl-2、Bax的表达。结果 5mol／L斑蝥素能明显抑制人胰腺癌SW1990细胞的生长，呈现凋亡特征。RT—PCR和Westernblot检测可见Bax、p53基因表达显著增加，而Bcl—2基因表达减少。结论 斑蝥素能诱导人胰腺癌细胞凋亡，其作用可能与上调p53、Bax基因和下调Bcl-2基因有关。     

EGCG对LoVo和SW480结肠癌细胞株的作用及对Notch1与Notch2基因表达的影响

目的:探讨绿茶提取物表没食子儿茶素没食子酸酯(EGCG)对结肠癌细胞株LoVo细胞和SW480细胞增殖的抑制作用,研究其对Notch1与Notch2的基因表达的影响,方法:体外培养LoVo细胞和SW480细胞,采用不同浓度的EGCG(10、20、35 mg/L)对其进行干预,MTT法检测EGCG对LoVo细胞和SW48...     

TMS对子宫内膜癌Ishikawa细胞增殖、凋亡的影响及机制探讨

目的 观察细胞色素酶P4501B1( CYP1B1)抑制剂2,3',4,5'-四甲氧基二苯乙烯(TMS)对人子宫内膜癌细胞株Ishikawa增殖和凋亡的影响,并探讨其机制.方法 采用免疫细胞化学方法检测Ishikawa细胞中的CYP1B1蛋白.采用MTT法检测10、20、40、80 μmol/L TMS培养24、48、72 h后Ishikawa细胞增殖抑制率,并于培养48 h时用倒置显微镜对Ishikawa细胞进行形态学观察.采用流式细胞术检测10、20、40、80 μmol/L TMS培养48 h后的Ishikawa细胞凋亡率、细胞周期以及细胞中的Bcl-2、Bax及Survivin.结果 CYP1B1蛋白在Ishikawa细胞中为阳性表达.TMS可呈时间和剂量依赖性抑制Ishikawa细胞增殖(P均＜0.05).用不同TMS培养48 h后镜下观察可见部分Ishikawa细胞皱缩变形,崩解坏死,细胞脱壁悬浮,并出现细胞核浓缩、核碎裂等细胞凋亡特征性形态学改变.TMS可剂量依赖性促进Ishikawa细胞凋亡,并使细胞周期中G0/G1期比例降低,G2/M期比例增高(P均＜0.05),同时降低凋亡相关蛋白Bcl-2和Surivin的表达(P均＜0.05),升高Bax的表达(P均＜0.05).结论 TMS能抑制人子宫内膜癌Ishikawa细胞的增殖,诱导细胞凋亡,阻滞细胞周期于G2/M期,其机制可能是通过下调凋亡抑制蛋白Bcl-2、Survivin,上调促凋亡蛋白Bax而实现的.     

Guggulsterone induces apoptosis of human hepatocellular carcinoma cells through intrinsic mitochondrial pathway

AIM: To investigate the effects of guggulsterone on the proliferation and apoptosis of human hepatoma Hep G2 cells in vitro and relevant mechanisms.METHODS: Human hepatocellular carcinoma Hep G2 cells and normal human liver L-02 cells were treated with different concentrations of guggulsterone(5-100 μmol/L) for 24-72 h. Cell proliferation was tested by MTT assay. Cell cycle and apoptosis were investigated using flow cytometry(FACS). Bcl-2 and Bax m RNA and protein expression was detected by real-time PCR and Western blot, respectively. TGF-β1, TNF-α, and VEGF contents were determined by ELISA.RESULTS: Guggulsterone significantly inhibited Hep G2 cell proliferation in a dose- and time-dependent manner. FACS showed that guggulsterone arrested Hep G2 cell cycle at G0/G1 phase. Guggulsterone induced apoptosis was also observed in Hep G2 cells, with 24.91% ± 2.41% and 53.03% ± 2.28% of apoptotic cells in response to the treatment with 50 μmol/L and 75 μmol/L guggulsterone, respectively. Bax m RNA and protein expression was significantly increased and Bcl-2 m RNA and protein expression was decreased. ELISA analysis showed that the concentrations of TGF-β1 and VEGF were significantly decreased and TNF-α concentration was increased.CONCLUSION: Guggulsterone exerts its anticancer effects by inhibiting cell proliferation and inducing apoptosis in Hep G2 cells. Guggulsterone induces apoptosis by activation of the intrinsic mitochondrial pathway.     

Inhibitory effect of caffeic acid phenethyl ester on the growth of SW480 colorectal tumor cells involves β-catenin associated signaling pathway down-regulation

AIM: To study the anti-tumor effect of caffeic acid phenethyl ester (CAPE) and the influence of CAPE on β-catenin associated signaling pathway in SW480colorectal cancer (CRC) cells.METHODS: SW480 cells were treated with CAPE at serial concentrations. The proliferative status of cells was measured by methabenzthiazuron (MTT) assay. Cell cycle and cell apoptosis were analyzed using flow cytometry (FCM). Western blotting assay was used to evaluate the protein level of β-catenin, c-myc and cyclinD1.β-catenin localization was determined by indirect immunofluorescence.RESULTS: CAPE displayed a strong inhibitory effect in a significant dose- and time-dependent manner on SW480cell growth. FCM analysis showed that the ratio of G0/G1 phase cells increased, S phase ratio decreased and apoptosis rate increased after SW480 cells were exposed to CAPE for 24 h. Pretreatment of SW480 cells with CAPE significantly suppressed β-catenin, c-myc and cyclinD1protein expression. CAPE treatment was associated with decreased accumulation of β-catenin protein in nucleus and cytoplasm, and concurrently increased its accumulation on the surface of cell membrane.CONCLUSION: CAPE can inhibit SW480 cell proliferation by inducing cell cycle arrest and apoptosis. Decreased β-catenin and the associated signaling pathway target gene expression may mediate the anti-tumor effects of CAPE.     

Effect of arsenic trioxide on human hepatoma cell line BEL-7402 cultured in vitro

AIM:To study the effect of a varying concentrations of arsenic trioxide on human hepatoma cell line BEL-7402 cultured in vitro and its mechanism of action.METHODS:The BEL-7402 cells were treated with arsenic trioxide (at the concentrations of 0.5 1 2&mgr;mol/L, respectively) for 4 successive days. The cell growth and proliferation were observed by cell counting and cell-growth curve. Morphologic changes were studied with electronmicroscopy. Flow cytometry was used to assay cell-DNA distribution and the protein expression of Bcl-2 and Bax detected by immunocytochemical method.RESULTS:The cell growth was significantly inhibited by varying concentrations of arsenic trioxide as revealed by cell counting and cell-growth curve, which was dose- and time-dependent. Arsenic trioxide treatment at 0.5, 1 and 2&mgr;mol/L resulted in a sub-G1 cell peak, the apoptosis rate of the control group was 9.31% and that of 0.5&mgr;mol/L arsenic trioxide 15.53%, no significant difference was seen between the two.The apoptosis rates of 1,2&mgr;mol/L arsenic trioxide were 19.10% and 21.87% respectively, which were much higher (both P < 0.05). Decrease of G(0)/G(1) phase cells and increase of S phase cells were observed by flow cytometry, suggesting the inhibition effect of 0.5, 1, 2&mgr;mol/L arsenic trioxide on BEL-7402 cell lay in the G(0)/G(1) phase. Morphologic changes such as intact cell membrane, nucleic condensation, apoptotic body formation were seen under transmission electronmicrescopy, whereas the 0.5mol/L arsenic trioxide-treated BEL-7402 cells showed decrease of nucleocytoplasmic ratio, round nucleus, well-differentiated organelles in the cytoplasm. The processes and microvilli on the cell surface of the experimental groups under scanning electron microscopy were significantly decreased. High expressions of Bcl-2 and Bax were detected in 1 and 2&mgr;mol/L arsenic trioxide-treated cells, these were 46%, 87.33% and 83.08%, 95.83% respectively, among which that of Bax was more significant. Arsenic trioxide treatment at 0.5&mgr;mol/L resulted in a higher expression level of Bcl-2 and lower expression level of Bax,which were 8.81% and 3.83% respectively, as compared with that of the control group (15.33%) (P(1)<0.01, P(2)<0.01).CONCLUSION:Arsenic trioxide not only inhibited proliferation but also induced apoptosis of human hepatoma cell line BEL-7402. The induced-apoptosis effect of 1,2&mgr;mol/L arsenic trioxide was related to the expression level of Bcl-2 and Bax.     

Inhibitory effect of caffeic acid phenethyl ester on the growth of SW480 colorectal tumor cells involves β-catenin associated signaling pathway down-regulation

AIM: To study the anti-tumor effect of caffeic acid phenethyl ester (CAPE) and the influence of CAPE on beta-catenin associated signaling pathway in SW480 colorectal cancer (CRC) cells. METHODS: SW480 cells were treated with CAPE at serial concentrations. The proliferative status of cells was measured by methabenzthiazuron (MTT) assay. Cell cycle and cell apoptosis were analyzed using flow cytometry (FCM). Western blotting assay was used to evaluate the protein level of beta-catenin, c-myc and cyclinD1. Beta-catenin localization was determined by indirect immunofluorescence. RESULTS: CAPE displayed a strong inhibitory effect in a significant dose- and time-dependent manner on SW480 cell growth. FCM analysis showed that the ratio of G0/G1 phase cells increased, S phase ratio decreased and apoptosis rate increased after SW480 cells were exposed to CAPE for 24 h. Pretreatment of SW480 cells with CAPE significantly suppressed beta-catenin, c-myc and cyclinD1 protein expression. CAPE treatment was associated with decreased accumulation of beta-catenin protein in nucleus and cytoplasm, and concurrently increased its accumulation on the surface of cell membrane. CONCLUSION: CAPE can inhibit SW480 cell proliferation by inducing cell cycle arrest and apoptosis. Decreased beta-catenin and the associated signaling pathway target gene expression may mediate the anti-tumor effects of CAPE.     

As2O3联合Aspirin对诱导肝癌细胞凋亡的影响

目的:观察As2O3与Aspirin联合应用对肝癌细胞Bel-7402的影响,并探讨其作用机制.方法:体外培养肝癌Bel-7402细胞,Aspirin、As2O3不同浓度孵育细胞.倒置显微镜观察细胞形态学改变,四甲基偶氮唑蓝(MTT)法检测As2O3和Aspirin单独及联合应用对Bel-7402细胞增殖情况的影响,流式细胞术观察细胞凋亡情况,并通过流式软件分析细胞周期变化.结果:As2O3及Aspirin对肝癌Bel-7402细胞生长均呈不同程度的抑制,且呈浓度依赖性.二者联合具有协同作用,药物联用组抑制率均显著高于单独应用同等剂量As2O3组和Aspirin组(P<0.05).2.0μmol/LAs2O3与0.2mmol/LAspirin联用组与2.0μmol/LAs2O3单药组相比,凋亡率从5.64%±0.56%提高到7.35%±0.62%,差异具有统计学意义(P<0.05).且通过对两组细胞周期检测发现,G1期细胞从40.52%±0.64%下降到32.03%±0.97%,G2期及S期细胞分别从9.57%±0.82%、50.41%±0.32%上升到13.66%±0.82%、54.37%±0.69%,Aspirin能显著增强As2O3诱导细胞集中于S及G2期的作用,从而增强其促凋亡作用.结论:Aspirin能增强As2O3诱导细胞凋亡的作用,该作用可能与影响细胞周期有关.     

熊果酸对肝星状细胞增殖与凋亡的影响

目的 体外观察熊果酸对肝星状细胞增殖与凋亡的影响,探讨熊果酸诱导肝星状细胞凋亡的可能作用机制. 方法 将不同浓度熊果酸作用于肝星状细胞HSC-T6及肝细胞L02,分别在药物作用24、48、72 h后用四甲基偶氮唑盐法检测熊果酸对HSC-T6及L02细胞增殖的影响;流式细胞仪检测熊果酸对HSC-T6凋亡的影响;光学显微镜观察熊果酸作用后细胞形态学变化情况;免疫细胞化学法检测HSC-T6中Bcl-2、Bax和Caspase-3蛋白的表达情况. 结果 各种浓度的熊果酸均可抑制HSC-T6细胞的增殖,且呈剂量-时间依赖性;当熊果酸浓度为25、50、75μmol/L时可促进L02细胞增殖,浓度＞75μmol/L则表现为抑制L02细胞增殖.在病理形态学方面,熊果酸作用HSC-T6细胞48 h后,光学显微镜下可见细胞缩小变圆、核浓缩等.25、50、75 μmol/L熊果酸作用HSC-T6细胞48 h后,流式细胞仪检测显示细胞凋亡率分别为10.30%±3.85%、21.87%±4.46%、31.33%±6.18%,比对照组(2.93%±1.60%)明显升高(P＜0.01).免疫细胞化学显示Bax及Caspase-3蛋白表达较对照组升高(P＜0.05),且呈剂量依赖性,而Bcl-2蛋白表达水平与对照组无明显差异(P＞0.05).结论 在体外熊果酸可较明显地抑制HSC-T6细胞增殖,诱导其凋亡;对L02细胞的生长具有双向调节作用.熊果酸诱导HSC-T6细胞凋亡可能与降低Bcl-2/Bax比值、激活Caspase-3蛋白有关.