维生素A对宫颈癌细胞增殖及凋亡的影响

目的观察维生素A对宫颈癌细胞增殖和凋亡的影响。方法采用MTT法检测5、7．5、10、15μg／ml维生素A处理后的人宫颈癌Caski细胞的增殖抑制率;采用流式细胞术检测维生素A处理后的Caski、Siha、Hela细胞的细胞周期,荧光酶标仪检测细胞线粒体膜电位;TUNEL法检测维生素A处理后Caski细胞的凋亡情况。结果5、7．5、10、15μg／ml维生素A处理24h后的Caski细胞增殖抑制率分别为32．1％±2．6％、47．3％±1．1％、66．4％±2．1％、70．8％±2．7％,处理48h后分别为38．3％±2．8％、52．6％±3．1％、72．5％±2．4％、80．0％±4．9％,其增殖抑制作用呈时间和浓度依赖性（P均〈0．05）;维生素A处理后,Caski、Siha、Hela细胞G0／G1和G2／M期细胞数量明显减少,S期细胞增多,细胞内线粒体电位分别为2．21±0．29、2．05±0．35、2．38±0．22,与处理前的0．32±0．08、0．24±0．15、0．41±0．06相比,P均〈0．05;维生素A处理后Caski细胞发生凋亡。结论维生素A可抑制宫颈癌细胞增殖,并诱导其凋亡。     

姜黄素对胰腺癌细胞株生长的抑制作用及可能机制

目的研究姜黄素对胰腺癌细胞增殖的体外抑制作用．探讨其抗癌作用的分子生物学机制。方法MTT法、Annexln V-FITC／PI双染法、细胞周期分析法、透射电镜等方法检测姜黄素对Pan02细胞生长和凋亡的影响．RT—PCR检测姜黄素对Pan02细胞Bax，Bcl-2，COX2，Bak．Survfvin mRNA的表达。结果(1)姜黄素抑制Pan02细胞生长呈量效关系；(2)姜黄素处理组细胞周期发生改变．G2／M期细胞比例增多、S期细胞比例减少；(3)姜黄素处理组细胞发生凋亡．表现为凋亡细胞比例增多，形态上出现明显细胞凋亡：(4)姜黄素处理组Pan02细胞Bcl-2和Bak mRNA表达水平显著下降．COX-2．Bax mRNA表达水平显著升高，Survivin mRNA的表达水平没有变化。结论姜黄素能够抑制Pan02细胞增殖，它可改变细胞周期、诱导细胞凋亡．Bcl-2家族而不是IAP家族(至少不是Survivin)参与了Pan02细胞的凋亡过程。     

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.     

瘦素对人胆管癌细胞QBC939增殖和凋亡的影响

目的观察瘦素对人胆管癌细胞QBC939增殖和凋亡的影响并初步探讨其可能的机制。方法在培养液中加入不同浓度的瘦素后,用四甲基偶氮唑盐（MTT）法检测细胞增殖,流式细胞仪观察细胞周期及凋亡情况,实时荧光定量PCR法检测增殖相关基因Cyclin D1和凋亡相关基因Bax、Bcl-2的表达情况,同时检测Caspase-3的活性。结果 MTT法显示瘦素可以促进QBC939细胞的增殖;流式细胞仪检测结果显示瘦素能明显降低G0/G1期细胞比例并提高S期细胞比例,细胞凋亡率也有明显降低;实时荧光定量PCR法显示瘦素（50 ng/ml）处理QBC939细胞24 h后,Cyclin D1mRNA的表达明显增高,Bcl-2 mRNA的表达量明显增高,而Bax mRNA的表达量下降,差异有统计学意义;而且瘦素作用QBC939细胞后能降低细胞的Caspase-3酶活性。结论瘦素可以明显的促进人胆管癌细胞QBC939从细胞周期G0/G1期向S期转换,进而促进细胞增殖,此外瘦素还可以抑制其凋亡。     

亚砷酸对肝癌BEL-7402细胞增殖、凋亡及其Bcl-2表达的影响

目的探讨亚砷酸（AA）对人肝癌BEL-7402细胞增殖、凋亡及其Bcl-2表达的影响。方法采用MTT比色法检测从作用后的BEL-7402细胞增殖抑制率,流式细胞术检测BEL-7402细胞周期及凋亡细胞,HE染色法观察凋亡细胞的形态,RT-PCR检测BEL．7402细胞的Bcl-2 mRNA,免疫组化法检测细胞的Bcl-2蛋白。结果1．0—8．0μmol／L的AA可使BEL-7402细胞增殖抑制率上升,能诱导BEL-7402细胞凋亡并阻滞细胞周期于S、G2／M期,呈剂量依赖性;8．0μmol／L的AA作用BEL-7402细胞48h后,细胞呈现明显的凋亡形态改变,其Bcl-2 mRNA及蛋白表达明显减弱。结论AA体外有抑制BEL-7402细胞增殖及诱导凋亡的作用,且呈时间、剂量依赖性,其作用机制可能与降低其Bcl-2表达有关。     

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.     

青蒿琥酯对U14细胞的体内外抑制作用及机制

目的 观察青蒿琥酯（Art）对小鼠宫颈癌U14细胞体内外抑制作用及其可能的作用机制。方法 MTT法检测不同浓度Art对体外培养的U14细胞增殖的影响;建立小鼠U14腹水瘤和实体瘤模型,分别用不同浓度的Art治疗,并设阴性和阳性对照组;观察Art对实体瘤抑瘤率,腹水瘤小鼠的生命延长率;免疫组化法检测实体瘤中Bcl-2和Bax蛋白表达,流式细胞仪分析腹水瘤小鼠U14细胞周期。结果 应用Art后U14细胞增殖显著抑制,其IC50为62．77μg／ml;实体瘤最大抑瘤率为52．59％,腹水瘤生命延长率为76．7％;实体瘤组织标本中Bax蛋白阳性率明显升高,Bcl-2蛋白阳性率明显降低;细胞周期分析示S期细胞数明显减少,G0、G1期的细胞数增加。结论 Art可抑制U14细胞体内及体外的增殖;其机制可能为上调Bax蛋白表达,下调Bcl-2表达,将肿瘤细胞生长抑制在G0、G1期。     

吲哚美辛对前列腺癌DU145细胞增殖与凋亡的影响及机制探讨

目的观察吲哚美辛对人激素非依赖性前腺癌细胞系DU145增殖和凋亡的影响，并探讨其作用机制。方法采用不同浓度的吲哚美辛处理DU145细胞。应用四甲基偶氮唑蓝（MTT）比色法检测并计算细胞增殖抑制率；流式细胞术检测细胞周期分布，并计算细胞凋亡率；采用酶联免疫吸附测定（ELISA）法测定细胞培养上清PGE2；应用RT-PCR法检测Bcl-2和Bax mRNA。结果吲哚美辛可明显抑制DU145细胞增殖（P〈0．05），并具有时间一剂量依赖性；经吲哚美辛作用后，S期细胞明显增多，G2/M期细胞减少，细胞出现凋亡峰；细胞上清中PGB量明显减少（P〈0．001）；Bcl-2 mRNA表达降低，BaxmRNA表达下降，Bcl-2／Bax下降（P〈0．05）。结论吲哚美辛对前列腺癌细胞DU145生长具有抑制作用，阻滞细胞向c2／M期转化，并促进其凋亡。其作用可能与抑制细胞PGE2释放、下调Bel-2／Bax有关。     

阿托伐他汀调控MMP-9、Cleaved Caspase-3、Bcl-2和Bax蛋白表达对胃癌细胞增殖、周期和凋亡的影响

目的探讨阿托伐他汀对胃癌细胞增殖、周期和凋亡的影响及其机制。方法取对数生长期的胃癌SGC-7901细胞,加入终浓度为0、20、60和100μmol/L的阿托伐他汀,采用MTT法检测细胞增殖,流式细胞仪检测细胞周期和凋亡,Western blotting检测细胞中MMP-9、Cleaved Caspase-3、Bcl-2和Bax蛋白的表达。结果阿托伐他汀能够呈时间-浓度依赖性抑制SGC-7901细胞增殖;阿托伐他汀作用48 h后,G_0/G_1期细胞所占比例、细胞凋亡率、Cleaved Caspase-3蛋白和Bax蛋白的表达浓度依赖性升高,S期细胞比例、G_2/M期细胞比例、MMP-9蛋白和Bcl-2蛋白浓度依赖性降低。结论阿托伐他汀能够抑制胃癌细胞增殖和诱导细胞凋亡,其作用机制可能与诱导细胞G_0/G_1期阻滞、上调Cleaved Caspase-3和Bax蛋白和下调MMP-9和Bcl-2蛋白有关。     

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。     

Aurora A激酶抑制剂VX-680对人宫颈癌细胞化疗敏感性的影响

目的探讨Aurora A激酶抑制剂VX-680对人宫颈癌细胞化疗敏感性的影响。方法以Aurora A激酶抑制剂VX-680抑制宫颈癌细胞株Caski中Aurora A的表达,再将宫颈癌细胞用不同浓度顺铂处理,Western Blot检测Aurora A蛋白受抑制情况,用流式细胞仪分析Aurora A表达下调后宫颈癌细胞生长抑制率和细胞凋亡率的变化。结果 Aurora A表达下调使顺铂对宫颈癌细胞的生长抑制率和细胞凋亡率均升高（P均〈0.01）。结论 Aurora A激酶抑制剂VX-680可使人宫颈癌细胞对顺铂的敏感性增强,抑制Aurora A可望提高顺铂对宫颈癌的治疗效果。     

Apoptosis Induced by Aspirin and 5-Fluorouracil in Human Colonic Adenocarcinoma Cells

Various biochemical, clinical and epidemiological studies have shown that aspirin (ASA) and other nonsteroidal anti-inflammatory drugs (NSAIDs) demonstrate antineoplastic properties, particularly in the gastrointestinal tract, inhibiting the proliferation of colorectal cancer cells. The mechanism of action may be prostaglandin mediated through inhibition of the COX enzymatic system. This includes two iso-enzymes, COX-I and COX-II, working in concert with the activation of apoptosis, activation of immune surveillance, inhibition of proliferation, and inhibition of carcinogen activation. 5-Fluorouracil (5-FU) has demonstrated activity against colorectal cancer, leading to apoptosis of neoplastic cells. We evaluated the effects of varying doses of ASA (0.5, 1, 1.5 mM), both as a single agent and in combination with 5-FU (50 μg) in HT-29, a colon adenocarcinoma cell line. Proliferation assays showed that aspirin at a concentration of 1 mM inhibits cell growth. Cells treated with ASA, both alone and in combination with 5-FU, demonstrated apoptotic activity with the up-regulation of Bax protein, which is consistent with 5-FU anticancer treatment. Furthermore, there was synergistic cell death with ASA and 5-FU. DNA fragmentation, TUNEL, and trypan blue exclusion methods indicated that a combination of ASA and 5-FU induces apoptosis in cells in a time- and concentration-dependent manner. This study serves to further elucidate the mechanism of action of ASA, and ASA in combination with 5-FU, in colorectal cancer as evidenced by its effect on the HT-29 cell line.     

MiR-628–5p Inhibits Cervical Carcinoma Proliferation and Promotes Apoptosis by Targeting VEGF

BackgroundIt has been reported that the dysregulation of microRNAs (miRNAs) is implicated in the biological processes of diverse diseases, including the tumorigenesis of human cancers. MicroRNA-628–5p (miR-628–5p) is differentially expressed and plays a critical role in several cancers, but the role of miR-628–5p in cervical cancer has not been well studied.MethodsThe TCGA database and RT-qPCR were used to evaluate the expression profile of miR-628–5p in cervical cancer tissues. Transfection efficiency of synthetic miRNAs was detected using RT-qPCR. The biological effects of miR-628–5p on cervical cancer cells were assessed by the CCK-8 assay, flow cytometry, western blot analysis, and the tube formation assay. The expression levels of key proteins involved in cell apoptosis, the cell cycle and the PI3K pathway were analyzed by western blot analysis. Bioinformatic analysis and the luciferase reporter assay were performed to investigate the targeted relationship between miR-628–5p and vascular endothelial growth factor (VEGF).ResultsMiR-628–5p was downregulated and negatively correlated with Ki-67 expression in cervical cancer tissues, and its low level predicted poor survival of patients. Functional assays indicated that miR-628–5p inhibited cell proliferation and promoted cell apoptosis. Mechanically, VEGF was verified to be a downstream target of miR-628–5p. Moreover, overexpression of VEGF could reverse the effects of miR-628–5p on VEGF/PI3K/AKT signaling, cell proliferation, apoptosis, the cell cycle and angiogenesis in cervical cancer.ConclusionsMiR-628–5p inhibited cervical cancer cell proliferation and promoted apoptosis by targeting VEGF.     

Nitric oxide-donating aspirin induces apoptosis in human colon cancer cells through induction of oxidative stress

Nitric oxide-donating aspirin (NO-ASA) is a promising chemoprevention agent against colon cancer and other cancers. It consists of traditional ASA to which a NO-releasing moiety is bound through a spacer. NO-ASA inhibits colon cancer cell growth several hundred times more potently than does ASA. In Min mice, NO-ASA inhibited intestinal carcinogenesis without affecting cell proliferation. Thus, we examined whether NO-ASA's most important cell kinetic effect is the induction of apoptosis. After confirming induction of apoptosis in Min mice, we studied the underlying mechanism in human colon adenocarcinoma cells. NO-ASA's spacer formed a conjugate with glutathione, depleting glutathione stores. This induced oxidative stress (increased intracellular levels of peroxides and O(2)(.-)) leads to apoptosis by activating the intrinsic apoptosis pathway. NO-ASA disrupted adherens junctions by inducing cleavage of beta- and gamma-catenin, resulting in cell detachment. NO-ASA inhibited Wnt signaling by a dual mechanism: at low concentrations it blocked the formation of beta-catenin/Tcf complexes (dominant mechanism), and at higher concentrations it also cleaved beta-catenin. These findings provide a mechanism of action by a potent chemopreventive agent, underscore the significance of these pathways in regulating cell death in the context of cancer chemoprevention, and present a paradigm for developing agents with enhanced cancer cell growth inhibitory properties.     

Additive inhibition of colorectal cancer cell lines by aspirin and bortezomib

Purpose  

To investigate the effect of cyclooxygenase-2 (Cox-2) inhibitor aspirin (acetylsalicylic acid, ASA) and proteasome inhibitor bortezomib in the proliferation and apoptosis of colorectal cancer cell lines.     

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。     

Paradoxical effect of aspirin on the growth of C6 rat glioma and on time of development of ENU-induced tumors of the nervous system

PURPOSE: Administration of acetylsalicylic acid (ASA), an inhibitor of the synthesis of prostaglandins and thrombzoxanes, decreases the incidence of colorectal cancer and other neoplasms and inhibits in vitro some tumor growth. We studied the effect of various doses of ASA on the growth of C6 glioma implanted in rats as well as the effect of chronic administration of ASA on time of development and incidence of tumors of the central nervous system (CNS) induced by prenatal exposure to ethylnitrosourea (ENU). METHODS: In a controlled study, various doses of ASA, 12.5, 25, 50, 100, 200, 300, and 400 mg/kg per day, were administered to Wistar rats in whom a subcutaneous C6 glioma had been transplanted. Changes in tumor size, histologic characteristics, mitotic index, cell proliferation, and vascular density were studied. In a parallel experiment, we administered ASA (70 mg/kg per day) to rats who were prenatally exposed to ENU; treatment started on day 50 of age, and continued until the end of the experiment at day 400. The time of tumor development as well as incidence, localization, and histological diagnosis were compared with matched controls. RESULTS: A paradoxical effect of ASA administration was observed on the dynamics of cell proliferation of C6 glioma. When high ASA doses were administered (200 or 400 mg/kg per day), tumor volume, cell proliferation, vascular density, and mitotic index increased. In contrast, when low doses were administered (12.5 or 25 mg/kg per day) the tumor size diminished. In the second experiment, localization and incidence of CNS tumors induced by ENU were similar in animals treated with ASA and in controls; however, in rats treated with ASA the time of tumor development was shortened. CONCLUSIONS: The growth-promoting effects of high doses of ASA found in the present study in both transplanted and chemically-induced brain tumors, might be due to the blockage of autocrine inhibitory factors dependent on the cyclooxygenase pathway or by increased vascular permeability and blood supply to the tumor due to inhibition of platelet aggregation. In contrast, the inhibition of tumor growth obtained with low ASA doses in transplanted glioma might be due to different mechanisms such as the induction of apoptosis.     

Trop2 gene: a novel target for cervical cancer treatment

Object

Trop2 plays an important role in proliferation and invasion of tumors. Extensive research has shown that the expression level of Trop2 is closely related to the progress of cervical diseases. This study was to explore the effects of Trop2 on cell proliferation and apoptosis in cervical cancer.

Methods

Trop2 was knocked down by shRNA in CaSki cells. The expression level of mRNA and protein was detected by real-time PCR and western blot, respectively. Cell proliferation was determined by CCK-8 and clone formation assay; apoptosis was measured by flow cytometry; cell cycle and apoptosis-related proteins cyclinD1, P53, bcl-2, bax, caspase 3, 8 and 9 were analyzed as well to investigate possible mechanism.

Results

Trop2 expression was effectively repressed in CaSki cells by Trop2 shRNA, which resulted in inhibition of proliferation and colony formation, whereas apoptosis rate was significantly increased. Furthermore, in Trop2 knockdown CaSki cells, the expression of cyclinD1 and bcl-2 was significantly down-regulated, while that of P53 and bax was up-regulated accompanied by increased activities of caspase 9 and 3 but not caspase 8.

Conclusions

Trop2 is important in proliferation and apoptosis regulation in CaSki cells, which may become a novel target for cervical cancer treatment.     

Aspirin-Induced Apoptosis in Human Gastric Cancer Epithelial Cells: Relationship with Protein Kinase C Signaling

This study examined the relationship of protein kinase C (PKC) signaling with apoptosis induced by aspirin (ASA) in gastric surface cancer cells (AGS cell line). We found increased expression of two PKC isoforms (α and β_II) that translocated from the cytosol into the cell membrane fraction after ASA (40 mM) stimulation. PKC β_I expression markedly decreased in response to ASA treatment. This process was independent of caspase activation because no caspase inhibitors used (i.e., inhibitors to caspase 3, 6, 7, 8, and total caspase activity) significantly changed PKC processing, although inhibition of caspase cascade activity markedly attenuated the apoptosis induced by ASA as measured by DNA-histone complex formation. Upstream PKC signaling induced by ASA seems to play an important role in the regulation of apoptosis because PKC inhibitors significantly reduced the magnitude of DNA-histone complex formation. We conclude that ASA-induced apoptosis in gastric cancer cells is mediated, at least in part, through a PKC mechanism involving the (α) and (β) isoforms and that PKC signaling operates upstream of the caspase cascade, which when activated elicits its downstream effects on DNA degradation.