Cytotoxic Activities of Total Saponins from Plena Clematis on Human Tumor Cell Lines In Vitro

Objective: To investigate the anti-proliferative effects of saponins prepared from Plena Clematis (PC) cultured in Fujian Province, China on 4 human tumor cell lines and its possible anti-tumor mechanism. Methods: The growth inhibition assays of saponins on human esophageal squamous carcinoma cell line (EC9706), human hepatoma cell line (HepG-2), human oral cancer cell line (KB) and human gastric cancer cell line (BGC-823) were evaluated in vitro by thiazolyl blue (MTT) method. The inhibitory effects on EC9706 treated with different concentrations of saponins (15.62, 31.25, 62.50, 125, 250 and 500 μg/mL) were performed in vitro by MTT method. The morphology and nuclear staining with acridine orange/ethidium bromide of EC9706 cells treated with saponins were illustrated under an inverted phase fluorescence microscope. The apoptotic effects of saponins were further evaluated by annexin-V/propidium iodide dual staining experiment to examine the occurrence of phosphatidylserine externalization onto the cell surface by a flow cytometer. Results: MTT assay showed that the saponins could inhibit the proliferation of 4 tumor cell lines. Among them, the maximum inhibition rate of 73.1% was detected in EC9706 cells at the saponins concentration of 250 μg/mL for 24 h. Further investigation indicated that the saponins induced EC9706 cells apoposis. The EC9706 cells presented apoptotic characteristics when treated with saponins, including that the morphologies of EC9706 cells were appeared round-shaped with higher refraction, and the cell nuclear stained orange with EB after 250 μg/mL saponins exposure. The flow cytometry analysis results showed that the induction of cell cycle arrest in apoptotic system may participate in the anti-proliferative activity of saponins on EC9706 cells. Conclusion: The saponins from PC exhibited significant cytotoxicity against human EC9706, KB, BGC-823, and HepG-2 cells and might be beneficial to development of ethnic pharmaceutical plant for potential anti-tumor drugs.     

HOXA1基因反义寡核苷酸对食管癌细胞生长的影响

  目的  探讨同源异形盒A1(HOXA1)基因反义寡核苷酸（ASODN）对食管癌细胞增殖、凋亡、侵袭和迁移的影响及机制。  方法  采用蛋白免疫印迹（Western blot）检测正常食管上皮细胞Het-1A和人食管鳞癌TE-1、EC9706和Eca109细胞HOXA1蛋白的表达,筛选高表达的食管鳞癌细胞进行后续实验;设计合成HOXA1 ASODN链、正义寡核苷酸(SODN)链及无义寡核苷酸（N-ODN）链;将筛选出的高表达的食管鳞癌细胞分为HOXA1 ASODN组（5、10、15 μmol/L的HOXA1 ASODN转染Eca109细胞）、对照组（细胞常规培养,不进行细胞转染）、SODN组（细胞转染15 μmol/L的SODN）和N-ODN组（细胞转染15 μmol/L的N-ODN）。采用噻唑蓝(MTT)法、流式细胞术、Transwell小室分别检测细胞活力、凋亡率及侵袭迁移能力;Western blot检测HOXA1、磷酸化的丝氨酸苏氨酸激酶（p-AKT）、细胞增殖核抗原(PCNA)、基质金属蛋白酶2(MMP-2)、B细胞淋巴瘤-2蛋白（B-cell lymphoma 2,Bcl-2）和Bcl-2相关X蛋白(Bax)蛋白表达。  结果  与正常食管上皮细胞Het-1A比较,人食管鳞癌TE-1、EC9706和Eca109细胞HOXA1蛋白表达均升高,差异有统计学意义（P<0.05）。HOXA1蛋白在Eca109细胞表达最高,因此选用Eca109细胞进行后续实验。转染HOXA1 ASODN的Eca109细胞HOXA1蛋白表达降低（P<0.05）。随着Eca109细胞转染HOXA1 ASODN浓度及时间增加,Eca109细胞活力降低,与对照、SODN、N-ODN组比较差异有统计学意义（P<0.05）。15 μmol/L的HOXA1 ASODN转染Eca109细胞后,与对照组比较,细胞侵袭和迁移能力降低,凋亡率升高,p-AKT、PCNA和MMP-2蛋白表达降低,Bax蛋白表达升高（P<0.05）。  结论  HOXA1基因反义寡核苷酸可抑制食管癌细胞增殖、侵袭和迁移能力,并诱导凋亡,机制与抑制磷脂酰肌醇3-激酶（PI3K）/AKT信号通路可能有关。     

EC9706和Eca109细胞中雷帕霉素靶蛋白信号通路激活状态观察

目的:观察低分化的食管鳞癌细胞EC9706和高分化的食管鳞癌细胞Eca109中雷帕霉素靶蛋白(mTOR)信号转导通路的激活状态.方法:采用细胞免疫组织化学方法检测EC9706和Eca109细胞中mTOR及其下游靶分子p70S6K的表达和定位,并采用RT-PCR和Western blot方法分别从mRNA及蛋白水平检测此通路的活性.结果:在2种细胞中mTOR均有表达,且在EC9706细胞中的表达水平高于Eca109(P＜0.05);EC9706细胞中mTOR下游靶点的磷酸化水平高于Eca109细胞(P＜0.05).结论:在2种食管鳞癌细胞中,mTOR信号通路均特异性激活;但激活状态与细胞的分化程度有关,细胞分化程度低者通路的激活水平较高.     

Tonglian Decoction(通莲汤) Arrests the Cell Cycle in S-phase by Targeting the Nuclear Factor-Kappa B Signal Pathway in Esophageal Carcinoma Eca109 Cells

Objective:To investigate the anti-tumor activity and molecular mechanism of Tonglian Decoction(通莲汤,TLD) on esophageal carcinoma Eca109 cells.Methods:Eca109 cells were treated with TLD and its separated formulae,including the clearing-heat and detoxification formula(Q),activating-blood and promoting-qi formula(H) and nourishing-yin and blood formula(Z).Cell proliferation was measured using the 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2-H-tetrazolium bromide assay,cell morphology was observed using a microscope,the cell cycle was measured using flow cytometry and the activity of the nuclear factor-kappa B(NF-κB) signal pathway was detected by Western blot.Results:The half maximal inhibitory concentrations of TLD,Q and H were 386,771 and 729 mg/L,respectively.TLD,Q and H significantly inhibited cell proliferation,with 69.43%,60.84%and 61.90%of treated cells in the G1 phase of the cell cycle.The percentage of cells in S phase increased significantly after treatment with TLD,Q,and H compared with the control group(P0.05),and TLD showed the strongest effect.Z had no influence on the cell cycle compared with the control group(P0.05).Western blot detection indicated slight differences in the inhibition of the NF- k B pathway by the different formulae.TLD formula strongly inhibited IKKβ,NF-κB,interleukin-6 and tumor necrosis factor-α expression compared with the control group.Conclusions:TLD inhibited Eca109 cell proliferation by arresting cells in S phase.The possible mechanism might be related to inhibiting the NF- κB transduction cascade.The combination of the herbs found in the three separate formulae,H,Q and Z,work synergistically in TLD to produce the inhibitory effects of TLD treatment on Eca109 proliferation.     

硒酸酯多糖对人食管鳞癌Eca109细胞增殖及凋亡的影响

目的研究硒酸酯多糖(KSC)对人食管鳞癌Eca109细胞增殖及凋亡的影响,并初步探讨其作用机制。方法甲基噻唑基四唑(MTT)法检测不同浓度KSC对Eca109细胞增殖的影响;流式细胞术观察KSC对Eca109细胞凋亡的影响;Westernblot技术检测KSC对Eca109细胞核转录因子-κB(NF-κB)蛋白表达水平的影响。结果 KSC可明显抑制Eca109的增殖(P<0.05),并呈时间及浓度依赖性;经KSC作用后,Eca109细胞的凋亡率随KSC作用时间的延长(24、48、72h)及KSC浓度的增加(30、60、120μg/mL)而明显升高(P<0.01);KSC(60、120μg/mL)显著下调Eca109细胞核中NF-κB蛋白水平(P<0.01)。结论 KSC对Eca109细胞具有抑制增殖、诱导凋亡作用,其作用机制可能与抑制NF-κB信号通路有关。     

硒蛋氨酸对食管癌放射抗拒细胞药物耐受性的影响

目的:研究硒蛋氨酸对食管癌放射抗拒细胞药物耐受性的影响。方法:以食管癌EC9706细胞为研究对象,建立放射抗拒的食管癌EC9706细胞株EC9706R,研究硒蛋氨酸对EC9706R细胞的影响。结果:EC9706R细胞耐药指数是EC9706细胞的1.24倍,硒蛋氨酸浓度大于4μmol/L时明显降低EC9706R细胞对顺铂的药物耐受性(P<0.05)。结论:硒蛋氨酸对食管癌放射抗拒细胞的药物耐受性具有一定的逆转作用。     

选择性环氧合酶-2抑制剂NS-398对食管癌细胞株EC9706的生长抑制作用

目的:探讨NS-398对人食管癌细胞株EC9706的生长抑制作用。方法:采用3H-TdR掺入法检测不同浓度(0、10、20、50、100μmol/L)和作用24、48、72、96h的NS-398对细胞的增殖抑制效应;采用流式细胞术(FCM)及DNA片段分析法检测NS-398诱导的细胞凋亡情况。结果:EC9706经不同浓度的NS-398处理后,实验组3H-TdR掺入量明显减少,具有时间和剂量依赖关系,与对照组比较差异显著(P<0.05或P<0.001)。FCM检测发现实验组在G1期前出现亚倍体凋亡峰,细胞凋亡率达(45.23±1.08)%,并出现典型的细胞凋亡梯带;而对照组无凋亡峰出现,细胞凋亡率为(2.14±0.28)%,两组比较有显著性差异(P<0.001)。结论:NS398对食管癌细胞株EC9706细胞具有增殖抑制作用和诱导细胞凋亡作用。     

奥曲肽对食管癌细胞株Eca9706增殖的影响

目的 研究奥曲肽对食管癌细胞株Eca9706增殖的影响。方法 将不同浓度的奥曲肽加入食管癌细胞．用四甲基偶氮唑蓝(MTT)法测定细胞生长抑制效应。^3H-胸腺嘧啶核苷(^3H-TdR)掺入实验测定对DNA合成的影响,显微镜下观察细胞形态变化，流式细胞仪(FCM)检测细胞周期。结果 奥曲肽对Eca9706细胞的生长及DNA合成均有抑制作用。显微镜下可见明显的细胞病变，细胞变圆、变小、脱落，FCM显示奥曲肽作用后，G0／G1期细胞增多，S期、G2／M期细胞减少。结论 奥曲肽能明显抑制食管癌细胞株Eca9706的DNA合成，并能形成G0／G1期阻滞，使细胞存活率下降，表明奥曲肽显著抑制Eca9706的增殖。     

自分泌运动因子对EC9706、Eca109及EC-1细胞丝切蛋白磷酸化的影响

目的:探讨自分泌运动因子(AMF)对食管鳞状细胞癌细胞中丝切蛋白磷酸化水平的影响.方法:构建真核表达载体pEGFP-Cl-AMF和pcDNA3.1(+)-AMF,脂质体法转染食管鳞状细胞癌细胞EC9706、Eca109及EC-1,荧光显微镜观察EGFP-AMF融合蛋白在细胞中的定位,RT-PCR和Western Blot法检测转染细胞中AMF mRNA和蛋白的表达,Western Blot检测转染前后细胞中磷酸化丝切蛋白表达的变化.结果:EGFP-AMF融合蛋白均定位于3种细胞的胞质中;转染pcDNA3.1(+)-AMF、未转染及转染pcDNA3.1(+)的EC9706、Eca109及EC-1细胞中AMF mRNA表达(F分别为411.516、475.759和144.857,P均<0.001)及磷酸化丝切蛋白的表达(F分别为40.482、67.125和498.219,P均<0.001)差异均有统计学意义,转染pcDNA3.1(+)-AMF的细胞中AMF mRNA及磷酸化丝切蛋白的表达均较未转染和转染pcDNA3.1(+)的细胞显著增高(P<0.05).结论:AMF能够提高食管鳞状细胞癌细胞株丝切蛋白磷酸化水平.     

MiR-203抑制食管鳞癌Eca109细胞的增殖及侵袭

目的探讨microRNA分子miR-203对食管鳞癌Eca109细胞增殖及侵袭能力的影响。方法根据人源miR-203序列,设计并合成其双链模拟物。通过脂质体转染将miR-203模拟物分子导入食管鳞癌Eca109细胞中,转染无关microRNA模拟物作为对照。测定2组细胞的细胞倍增时间、细胞凋亡率以及侵袭细胞率,观察miR-203对Eca109细胞增殖及侵袭能力的影响。结果Eca109细胞转染miR-203后其细胞倍增时间为(26.1±0.5) h,较对照组(24.2±0.6) h明显延长(P<0.01);其凋亡细胞比例较对照组增加\[(4.5±0.4)% vs (3.7±0.4)%,P<0.05\];Transwell小室侵袭实验显示转染miR-203模拟物后,该组的侵袭细胞率明显低于对照组\[(39.2±5.8)% vs (49.5±6.8)%,P<0.05\]。结论miR-203能抑制Eca109细胞的增殖和侵袭能力,提示miR-203可能是食管鳞癌生物治疗的潜在靶点。     

云芝多糖-B对人食管癌细胞Eca109转移的影响

【目的】 应用新型云芝多糖-B(CVPs-B)作用食管鳞癌Eca109细胞,探讨其对Eca109细胞转移特性的作用?【方法】 Western blot检测CVPS-B作用后,食管鳞癌Eca109细胞CXCL12蛋白表达的变化,Transwell侵袭实验评估食管癌细胞侵袭能力的变化,MTT法观察食管癌细胞与Matrigel胶黏附能力的变化,划痕法检测食管癌细胞迁移能力的变化?【结果】 实验组Eca109细胞CXCL12蛋白表达水平较对照组显著降低(P < 0.05)?CVPs-B孵育后,食管癌Eca109细胞黏附?侵袭及迁移能力下降?【结论】CVPs-B降低食管癌细胞CXCL12蛋白表达,有效抑制食管癌Eca109细胞的转移潜能,提示CVPs-B可能可以通过CXCL12/CXCR4通路抑制食管鳞癌细胞转移特性?     

E-selectin及其配体介导食管癌细胞与血管内皮细胞早期粘附

目的探讨E-选择素（E-selectin）及其配体sLe A和sLe X在食管癌细胞和内皮细胞早期粘附中的作用。方法应用粘附实验检测食管癌细胞和血管内皮细胞的粘附。结果静息状态下,人食管癌细胞株EC9706和奇静脉内皮细胞株ECV304粘附较少,内皮细胞经脂多糖激活后,与人食管癌细胞株粘附显著增加。激活内皮细胞组、E-选择素单抗（1∶200）、E-选择素单抗（1∶400）、E-选择素单抗（1∶800）组相对粘附率（5.2900±0.790）、（1.8818±0.8289）、（1.9436±0.3935）、（3.1730±0.4887）,差异具有统计学意义（F值28.789,P值〈0.001）。sLe A、sLe抗体处理组相对粘附率分别为（2.5436±0.6789）、（3.1286±0.8306）,均较未处理（6.5170±0.9293）低,差异具有统计学意义（P〈0.01）。结论E-selectin及其配体sLe A和sLe X介导食管癌细胞和内皮细胞早期粘附,可能与食管癌转移有关。     

仙鹤草水提液对食管癌Eca109细胞生长的抑制作用

目的:研究仙鹤草水提液对人食管癌Eca109细胞生长的抑制作用及其可能机制.方法:MTT法测定0g/L、2 g/L、4 g/L、8 g/L、16 g/L的仙鹤草水提液分别作用于Eca109细胞24 h、48 h、72 h,观察对Eca109细胞生长的抑制作用;采用免疫组织化学染色技术检测16 g/L仙鹤草水提液作用72 h对Eca109细胞Bcl-2、P53蛋白表达的影响.结果:MTT结果显示16 g/L仙鹤草水提液作用48 h和72 h后Eca109细胞生长明显受抑;免疫组化结果显示16 g/L仙鹤草水提液作用72 h后Eca109细胞内Bcl-2蛋白表达下调,P53蛋白表达上调.结论:仙鹤草水提液体外能诱导Eca109细胞凋亡,其机制可能与下调Bcl-2蛋白表达及上调P53蛋白表达有关.     

DMSO对EC9706细胞端粒酶活性及生长的影响

目的　研究二甲基亚砜 (DMSO)对EC970 6细胞端粒酶活性及生长的影响。方法　用 1.3 %DMSO处理食管癌EC970 6细胞 ,TRAP -ELISA法检测细胞端粒酶活性的改变 ,流式细胞仪分析细胞周期的改变。结果　DMSO处理后的EC970 6细胞 ,端粒酶活性明显下降 ,且细胞周期明显改变 ,G1期细胞比率显著增高 ,S期细胞数显著降低。结论　DMSO可抑制EC970 6细胞端粒酶活性 ,使EC970 6细胞生长停滞于G1期 ,并诱导细胞凋亡。提示DMSO可用于食管癌的治疗     

肿瘤特异性Caspase-8表达载体对食管癌细胞Eca109体外增殖和凋亡作用的研究

目的研究肿瘤特异性Caspase-8表达载体对食管癌细胞Eca109体外增殖和凋亡作用。方法用脂质体法将人端粒酶催化亚单位(hTERT)启动子调控的肿瘤特异性表达载体hTERT-Caspase-8,瞬时转染端粒酶阳性的食管癌细胞株Eca109及端粒酶阴性的人胚肺成纤维细胞株MRC-5。结果转染hTERT-Caspase-8对细胞Eca109的生长具有显著抑制作用,细胞凋亡水平显著升高;转染hTERT-Caspase-8对MRC-5的生长和凋亡均无明显影响。结论上述发现提示hTERT启动子可以调控Caspase-8基因在食管癌细胞中靶向性表达,选择性抑制肿瘤细胞生长,促进肿瘤细胞凋亡,可能是肿瘤靶向性基因治疗中比较理想的转录调控元件。     

miR-155对食管癌EC109细胞增殖和侵袭能力的影响

目的 研究microRNA-155(miR-155)对高转移性人食管癌EC109细胞增殖和侵袭等生物学行为的影响.方法 以人食管癌EC109基因组DNA为模板,经PCR法扩增miR-155的前体序列,通过BamHⅠ和HindⅢ双酶切后将其亚克隆入真核表达载体pcDNA 3.1(-);然后将构建成功的pcDNA3.1(-)-pri-miR-155载体(命名为p-miR-155)体外瞬时转染人食管癌EC109细胞,利用qRT-PCR(quantitative Real-time PCR)法检测mR-155成熟体的表达水平,并利用MTT实验、克隆形成实验和划痕法检测EC109细胞的增殖、克隆形成以及体外迁移能力.结果 成功构建携miR-155的真核表达载体;与空白(Mock)和对照组(p-Ctrl)相比,转染后的EC109细胞过表达miR-155、p-miR-155载体转染组EC109细胞的增殖抑制明显增加(P<0.01),同时克隆形成能力(在100和1000个细胞/孔接种条件下)明显下降(P<0.01),以及伤口愈合能力下降(P<0.01).结论 过表达miR-155可显著抑制人食管癌EC109细胞的增殖和迁移能力,为食管癌的治疗提供了潜在的策略.     

白藜芦醇对人食道癌细胞生长和凋亡的影响

目的:探讨白藜芦醇对人食管癌EC9706细胞生长及凋亡影响。方法:分为正常组、溶剂组(加了DM-SO)、白藜芦醇组(分为0.2,0.4,0.8,1.6,3.2 mmol/L不同浓度),应用MTT比色法检测白藜芦醇对EC9706细胞体外生长的抑制作用;流式细胞仪测定细胞的周期和凋亡;电子显微镜观察细胞凋亡。结果:MTT实验观察,白藜芦醇对EC9706细胞生长有抑制作用,随浓度升高,时间延长作用增强,呈剂量-时间效应关系。白藜芦醇(3.2 mmol/L)作用EC9706细胞72 h抑制率达86.73%,凋亡率达47.53%。作用24,48,72 h后,半数细胞毒性作用所需浓度(CC50)及最大无毒浓度分别为3.15,3.01,1.14 mol/L及0.32,0.08,0.09 mmol/L。从低到高浓度(0.2-3.2 mmol/L)白藜芦醇使S期细胞比例逐渐下降,G0/G1细胞的比例逐渐增加。电子显微镜观察:白藜芦醇作用的EC9706食管癌细胞,呈明显的凋亡特征。结论:白藜芦醇可抑制人食管癌细胞EC9706增殖并可诱导细胞发生凋亡。使食管癌EC9706细胞周期呈G0/G1阻滞。白藜芦醇可能为食管癌提供一种新的治疗手段。     

RNA干扰沉默乏氧诱导因子1α对乏氧条件下食管鳞癌细胞化疗敏感性的影响

目的探讨RNA干扰技术沉默乏氧诱导因子（HIF）-1α对食管鳞癌EC9706细胞乏氧条件下化疗敏感性的影响及其机制。方法应用化学乏氧法[氯化钴（CoCl2）加入培养液的终浓度为75μmol／L]体外模拟肿瘤乏氧微环境。采用MTS比色法检测常氧培养组和乏氧培养组EC9706细胞在顺铂／紫杉醇作用下细胞的抑制率,以及RNA干扰后乏氧培养细胞在顺铂／紫杉醇作用下细胞的抑制率。应用Western印迹方法检测HIF-1α基因沉默后乏氧诱导HIF-1α蛋白表达变化。用流式细胞仪检测RNA干扰前后乏氧条件下EC9706细胞的细胞周期。结果针对HIF-1α基因的siRNA干扰技术,有效抑制乏氧诱导的HIF-1α蛋白表达。同一药物浓度常氧培养组细胞抑制率均明显高于乏氧培养组（均P〈0．05）。相同药物浓度及相同的乏氧条件下RNA干扰组抑制率均明显高于未转染组及转染control siRNA组（均P〈0.05）。相同的乏氧条件下转染HIF-1α siRNA与未转染组／转染无关对照siRNA组相比,S期显著增加（P〈0．05）、G1期细胞减少（P〈0．05）。结论乏氧条件下HIF-1α诱导EC9706细胞周期停止,可能是乏氧条件下细胞耐药的机制之一。RNA干扰可逆转食管癌细胞EC9706乏氧环境中化疗耐药。     

siRNA沉默CXCR4基因对食管鳞癌细胞EC9706体外侵袭能力的影响

目的:探讨siRNA沉默CXCR4基因对食管鳞癌EC9706细胞系体外侵袭能力的影响.方法:化学合成两对针对CXCR4基因的干扰序列siRNA1和siRNA2和一对荧光标记的阴性对照siRNA,转染人食管鳞癌EC9706细胞.荧光显微镜下观察转染效率,于转染后48 h采用半定量RT-PCR和Western Blot法检测各组细胞CXCR4 mRNA和蛋白表达水平的变化,Boyden侵袭小室检测各组细胞体外侵袭能力的变化.结果:与未转染组和转染阴性对照siRNA组相比,EC9706细胞转染两对CXCR4 siRNA48 h后,CXCR4 mRNA和蛋白表达水平明显下降(P<0.05),转染siRNA1组CXCR4 mRNA和蛋白下降尤为明显,未转染组和转染阴性对照siRNA组之间无明显差异(P>0.05).Boyden侵袭小室结果显示,转染CXCR4siRNA1和CXCR4 siRNA2组细胞穿膜数与未转染组和转染阴性对照siRNA组相比明显下降(P<0.05),未转染组和单纯转染脂质体转染试剂组之间无明显差异(P>0.05).结论:siRNA沉默CXCR4基因降低EC9706细胞CXCR4的表达和侵袭能力,为...     

Aspirin inhibits the proliferation of tobacco-related esophageal squamous carcinomas cell lines through cyclooxygenase 2 pathway

Background  Cigarette smoking has been verified as the risk factor of esophageal squamous cell carcinoma (ESCC). Overexpression of cyclooxygenase 2 (COX-2) is shown in ESCC. The objective of this study was to investigate the effects of cigarette smoking ethanol extract (EE) on the proliferation of the human ESCC cell lines, and to explore the correlation between the proliferation rate of human ESCC cell lines and the expression pattern of COX-2. Whether aspirin can inhibit the proliferation of the ESCC cell lines pretreated with EE, and regulate the mRNA expression levels of COX-2 are also examined.
Methods  Two human ESCC cell lines were selected. EC109 was poorly differentiated and EC9706 was highly differentiated. EC109 and EC9706 were treated with EE and aspirin for different time course. The cell growth of ESCC was measured by MTT reduction assay and the expression of COX-2 was measured by RT-PCR and Western blot analysis.
Results  EE promoted the proliferation of EC109 and EC9706 in dose- and time-dependent manners. In the concentration range (10−100 µg/ml for EE) and in the time range (24−72 hours) after addition of EE, the cell proliferation was prominent in an up-scaled manner respectively. Aspirin could inhibit the proliferation of cell lines EC109 and EC9706, pretreated with EE for 5 hours, in a dose-dependent manner. In the concentration range (0.5−8.0 mmol/L for aspirin), the cell growth inhibition was prominent in an up-scaled manner accordingly (P<0.05). The effect of EE on cell proliferation was correlated with the up-regulation of COX-2 gene. However, the cell growth inhibition of aspirin was correlated with the down-regulation of COX-2 gene.
Conclusions  EE can stimulate the proliferation of human ESCC cell lines EC109 and EC9706, most likely through up-regulating the expression of COX-2. Aspirin can inhibit the proliferation of ESCC cell lines induced by EE, which suggests it may be advantageous in the chemoprevention and therapy of human tobacco-related ESCC. And its effect is likely to be related with modulating COX-2 activity.