EphA2在缺氧条件下的表达及其对食管癌细胞体外三维培养的影响

目的:探讨在正常氧分压和缺氧条件下,食管癌细胞中上皮细胞激酶A2(EphA2)表达变化及其对体外三维培养的影响.方法:正常氧分压及缺氧条件下培养食管癌Ecal09及TE13细胞,RT-PCR及Western blot 分别监测细胞中EphA2表达的变化:EphA2 miRNA干扰质粒转染Ecal09和TE13细胞后,采...     

RNA干扰Akt对食管癌细胞株Eca109生物学特性的影响

目的:探讨RNA干扰沉默Akt对人食管鳞癌细胞体外增殖、迁移及血管生成拟态(VM)形成的影响.方法:应用倒置荧光显微镜观察Akt的干扰质粒转染食管癌细胞Eca109后绿色荧光蛋白的表达;采用Western blot方法检测Akt蛋白的表达;四甲基偶氮唑蓝(MTT)法检测转染前后细胞增殖能力的变化;Transwell方法...     

Experimental and clinicopathologic study on the relationship between transcription factor Egr-1 and esophageal carcinoma

AIM: To observe the growth suppression effect of exogenous introduction of early growth response gene-1 (Egr-1 gene) on esophageal carcinoma tissue as well as on esophageal carcinoma cell line Eca109 and to explore the potential application of Egr-1 gene in gene therapy of tumor. METHODS: Eukaryotic expression vector of PCMV-Egr-1 plasmid was introduced into Eca109 cell line which expressed no Egr-1 protein originally with lipofectamine transfection method. The introduction and expression of PCMV-Egr-1 plasmid into Eca109 cell line was confirmed by G418 selection culture, PCR amplification of neogene contained in the vector, Western blot analysis and immunocytochemical analysis. The cell growth curve, soft agar colony formation rate and tumorigenicity in SCID mice were examined to demonstrate the growth suppression effect of exogenous Egr-1 gene on Eca109 cell line. The Egr-1 mRNA and Egr-1 protein were also detected in 50 surgical specimens of esophageal carcinoma by in situ hybridization and immunohistochemistry. RESULTS: Exogenous Egr-1 gene was introduced successfully into Eca109 cell line and expressed Egr-1 protein stably. The transfected Eca109 cell line grew more slowly than control Eca109 as shown by cell growth curves, the soft agar colony formation rate (4.0% vs 6.9%, P < 0.01) and the average growth rate of tumor in SCID mice (35.5 +/- 7.6 vs 65.8 +/- 7.6, P < 0.05). The expression level of Egr-1 mRNA and protein significantly increased in dysplastic epithelia adjacent to cancer rather than in cancer tissues (65.8% vs 20.0% by ISH and 57.9% vs 0.01). CONCLUSION: Exogenous Egr-1 gene shows the strong effect of growth inhibition in Eca109 cell line. Egr-1 in the cancer tissue shows down-regulated expression that supports the inhibited function of Egr-1 in cancer growth and suggests Egr-1 may have an important role in gene therapy of esophageal carcinoma.     

血管内皮钙黏附素下调对食管鳞癌细胞血管生成拟态、增殖和凋亡的影响

背景：血管内皮钙黏附素（VE-cad）作为血管生成拟态的重要调控分子在多种高侵袭性肿瘤中均存在表达,参与肿瘤的发生、发展过程。前期研究发现食管鳞癌细胞中亦存在VE—cad表达。目的：探讨微小RNA（miRNA）干扰技术下调VE-cad对食管鳞癌细胞血管生成拟态形成、细胞增殖和凋亡的影响及其可能机制。方法：将已成功构建的VE—cadmiRNA干扰质粒稳定转染Eca109、TE13细胞,同时设置阴性对照组（转染空质粒）和空白对照组（未转染）。荧光显微镜观察单克隆转染效率,三维培养观察细胞管腔样结构形成的能力,RT—PCR和蛋白质印迹法分别检测VE-cad、EphA2、LN5γ2 mRNA和蛋白表达,MTT法和流式细胞术分别检测细胞增殖和凋亡。结果：荧光显微镜显示Eca109、TE13细胞稳定转染效率均达90％以上。与阴性对照组和空白对照组相比,干扰组细胞管腔样结构数目明显减少（P〈0．01）,VE—cad、EphA2、LN5γ2mRNA和蛋白表达明显受抑（P〈0．01）,细胞增殖能力明显下降（P〈0．05）,凋亡率明显增高（P〈0．05）。结论：miRNA干扰技术能有效抑制食管鳞癌细胞Eca109、TE13的VE-cad表达。VE—cad通过下调EphA2和LN5γ2表达抑制血管生成拟态的体外形成,并影响细胞增殖和凋亡。VE—cad可能成为食管鳞癌分子靶向治疗的新靶点。     

磁性纳米控释紫杉醇对食管癌Eca109细胞株生长的影响

目的:观察不同浓度磁性纳米控释紫杉醇对食管癌细胞Eca109的影响及与不同化疗药物的对比.方法:取对数生长期的食管癌Eca109细胞作细胞增殖抑制实验,实验组分别给予不同浓度的磁性纳米控释紫杉醇和5-氟尿嘧啶、泰素,同时设立二甲基亚砜(DMSO)和RPMI1640液对照,测定24,48,72h三个时间段的吸光度值,计算抑制率.经不同浓度的磁性纳米控释紫杉醇作用72h后,用电镜观察细胞超微结构,同时用流式细胞仪测定细胞周期和细胞凋亡.结果:MTT实验显示磁性纳米控释紫杉醇可抑制食管癌细胞增殖,与5-氟尿嘧啶,泰素相比,具有缓释性(P<0.01);电镜可发现药物作用组细胞核固缩、解聚以及凋亡小体;流式细胞仪检测显示G1峰前有明显的凋亡峰;细胞周期分析提示磁性纳米控释紫杉醇可将Eca109细胞阻滞于G2-M期,且与浓度相关.结论:磁性纳米控释紫杉醇对人食管癌细胞Eca109的生长有明显的抑制作用,使细胞分裂阻滞于G2-M期,并诱导细胞凋亡,且具有缓释效果.     

Effect of S1P5 on proliferation and migration of human esophageal cancer cells

AIM:To investigate the sphingosine 1phosphate (S1P) receptor expression profile in human esophageal cancer cells and the effects of S1P5 on proliferation and migration of human esophageal cancer cells. METHODS: S1P receptor expression profile in human esophageal squamous cell carcinoma cell line Eca109 was detected by semiquantitative reverse trans cription polymerase chain reaction. Eca109 cells were stably transfected with S1P5EGFP or controlEGFP constructs. The relation between the responses of cell prol...     

Bile salts inhibit growth and induce apoptosis of human esophageal cancer cell line

AIM: To explore the effect of six bile salts, including glycoc holate (GC), glycochenodeoxycholate (GCDC), glycodeoxy cholate (GDC), taurocholate (TC), taurochenodeoxycholate (TCDC), taurodeoxycholate (TDC), and two bile acids including cholic acid (CA) and deoxycholic acid (DCA) on esophageal cancer Ecal09 cell line. METHODS: Eca109 cells were exposed to six bile salts, two bile acids and the mixed bile salts at different concentrations for 24-72 h. 3-[4,5-Dimethylthiazol-2-yl]-2,5-diphenyl-tetrazolium bromide (MTT) assay was used to detect the cell proliferation. Apoptotic morphology was observed by phase-contrast video microscopy and deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) assay. Sub-G1 DNA fragmentations and early apoptosis cells were assayed by flow cytometry (FCM) with propidium iodide (PI) staining and annexin V-FITC conjugated with PI staining. Apoptosis DNA ladders on agarose were observed. Activation of caspase-3 was assayed by FCM with FlTC-conjugated monoclonal rabbit anti-active caspase-3 antibody and expressions of Bcl-2 and Bax proteins were examined immunocytochemically in 500 μmol/L-TC-induced apoptosis cells. RESULTS: Five bile salts except for GC, and two bile acids and the mixed bile salts could initiate growth inhibition of Ecal09 cells in a dose- and time-dependent manner. TUNEL, FCM, and DNA ladder assays all demonstrated apoptosis induced by bile salts and bile acids at 500 μmol/L, except for GC. Early apoptosis cell percentages in Eca109 cells treated with GCDC, GDC, TC, TCDC, TDC, CA at 500 μmol/L for 12 h, DCA at 500 μmol/L for 6 h, and mixed bile salts at 1 000 μmol/L for 12 h were 7.5%, 8.7%, 14.8%, 8.9%, 7.8%, 9.3%, 22.6% and 12.5%, respectively, all were significantly higher than that in control (1.9%). About 22% of the cell population treated with TC at 500 μmol/L for 24 h had detectable active caspase-3, and were higher than that in the control (1%). Immunocytochemical assay suggested that TC down-regulated Bcl-2 protein level and up-regulated Bax protein level. CONCLUSION: GCDC, GDC, TC, TCDC, TDC, CA and DCA, except for GC, can inhibit growth and induce apoptosis of esophageal cancer Ecal09 cells. Activation of caspase-3, decreased Bcl-2 protein and increased Bax protein are involved in TC-induced apoptosis of Ecal09 cells.     

槲皮素对食管癌Eca109细胞迁移侵袭及血管生成的影响

目的研究槲皮素(Que)对人食管癌Eca109细胞迁移侵袭及血管生成的影响。方法分别用5μg/mL、10μg/mL Que处理Eca109细胞,通过平板克隆形成实验、创伤愈合实验及Transwell实验观察其克隆形成能力以及迁移和侵袭能力的改变。制备Eca109肿瘤条件培养基,诱导人脐静脉内皮细胞CRL-1730迁移及成管,观察Que对其的影响。采用蛋白质免疫印迹法(Western blot)测定Que对Eca109细胞的血管内皮生长因子-A(VEGF-A)、基质金属蛋白酶2(MMP2)、MMP9蛋白表达的影响。结果 10μg/mL Que可显著抑制Eca109细胞的单细胞克隆形成能力(P0.05),而5μg/mL Que则不影响Eca109细胞的单细胞克隆形成能力(P0.05)。10μg/mL Que可抑制Eca109细胞的迁移和侵袭(P0.05),5μg/mL Que仅抑制Eca109细胞的侵袭(P0.05),但并不明显影响其迁移(P0.05)。5μg/mL、10μg/mL Que均可抑制Eca109肿瘤条件培养基诱导的CRL-1730细胞迁移和管腔形成(P均0.05),且10μg/mL Que的效果更明显。10μg/mL Que可明显降低VEGF-A、MMP2和MMP9的表达(P均0.05),5μg/mL Que仅降低MMP2的表达(P0.05)。结论 Que可以抑制Eca109细胞的迁移、侵袭及血管新生,并呈剂量依赖性。     

Role of stress-activated MAP kinase P38 in cisplatin- and DTT-induced apoptosis of the esophageal carcinoma cell line Eca109

AIM: To study the role of P38 kinase in esophageal cancer cell apoptosis induced by genotoxin, cisplatin and the unfolded protein response (UPR) inducer, dithiothreitol (DTT). METHODS: Esophageal carcinoma cell line Eca109 was cultured in RPMI 1640 medium to 70% confluency and treated with either cisplatin, DTT, or cisplatin plus DTT in the presence or absence of P38 inhibitor, SB203580. The untreated cells served as the control. The esophageal carcinoma cell apoptosis was detected by agarose gel DNA ladder analysis and quantified by flow cytometry. The P38 phosphorylation was detected by immunohis-tochemistry using antibodies specific to phosphorylated P38 protein. RESULTS: (1) Both cisplatin and DTT induced apoptosis in the esophageal cancer cell line Eca109 as shown by DNA ladder formation; (2) As detected by antibodies specific for the phosphorylated P38 protein (p-P38), both cisplatin and DTT treatments activated the stress-activated enzyme, MAP kinase P38. The number of positive cells was about 50% for the treatment groups, comparing to that of 10% for untreated group. DTT treatment, but not cisplatin treatment, induces nuclear localization of p-P38; (3) As measured by flow cytometry, inhibition of P38 activity by SB203580 blocks DTT- and cisplatin-induced apoptosis. The rates for DTT, cisplatin, and DTT plus cisplatin-induced apoptosis were 16.8%, 17.1%, and 21.4%, respectively. Addition of the SB compound during the incubation reduced the apoptotic rate to about 7.6% for all the treatment groups, suggesting that P38 activation is essential for cisplatin- and DTT-induced apoptosis in Eca109 cells. CONCLUSION: (1) Both DTT and cisplatin were able to induce apoptosis in esophageal cancer cell line Eca109; (2) P38 MAP kinase is essential for DTT- and cisplatin- induced apoptosis in Eca109 cells; (3) P38 activation may be the common signaling component relaying the multiple upstream signaling events to the downstream cell death program.     

mi R-382 functions as a tumor suppressor against esophageal squamous cell carcinoma

AIM To explore the effect of mi R-382 on esophageal squamous cell carcinoma(ESCC) in vitro and its possible molecular mechanism.METHODS Eca109 cells derived from human ESCC and Het-1A cells derived from human normal esophageal epithelium were used. Lentivirus-mediated mi R-382 was overexpressed in Eca109 cells. The effect of mi R-382 on cell proliferation was evaluated by MTT and colony formation assay. For cell cycle analysis, cells were fixed and stained for 30 min with propidium iodide(PI) staining buffer containing 10 mg/m L PI and 100 mg/m L RNase A, and analyzed by BD FACSCalibur? flow cytometer. For cell apoptosis assay, cells were stained with an Annexin V-FITC/PI Apoptosis Detection Kit according to the manufacturer's instructions and analyzed by a dual-laser flow cytometer. Cell invasion and migration abilities were determined through use of transwell chambers, non-coated or pre-coated with matrigel. Levels of proteins related to cell growth and migration were examined by western blotting.RESULTS Endogenous mi R-382 was down-regulated in Eca109 cells compared with Het-1A. Introduction of mi R-382 not only significantly inhibited proliferation and colony formation, but also arrested cell cycle at the G2/M phase, as well as promoted apoptosis and autophagy in Eca109 cells. Migration, invasion and epithelialmesenchymal transition of Eca109 cells were suppressed by overexpressing mi R-382. Western blotting results showed that mi R-382 inhibited the phosphorylation of m TOR and 4E-BP1. CONCLUSION mi R-382 functions as a tumor suppressor against ESCC development and metastasis, and could be considered as a potential drug source for the treatment of ESCC patients.     

缺氧诱导因子-1α与EphA2在食管鳞状细胞癌中的表达及其相关性研究

目的 检测缺氧诱导因子-1α (HIF-1α) 蛋白与EphA2蛋白在食管鳞状细胞癌中的表达定位并探讨二者表达的相关性.方法 采用细胞免疫荧光法检测HIF-1α与EphA2在食管鳞状细胞癌细胞株Eca109中的表达与定位;采用免疫组化法检测HIF-1α与EphA2在41例食管鳞状细胞癌和25例正常食管组织中的表达;常氧和缺氧条件下,Western 印迹法检测食管鳞状细胞癌细胞株Eca109和TE13经RNA干扰(RNAi)技术特异性沉默HIF-1α后EphA2表达的变化.结果 ①细胞免疫荧光结果显示HIF-1α和EphA2均在Eca109细胞胞质表达.②免疫组化结果显示HIF-1α在食管鳞状细胞癌和正常食管组织中的阳性表达率分别为70.73%(29/41)和0%(0/25),两者比较差异有统计学意义(P<0.05).EphA2在食管鳞状细胞癌和正常食管组织中的阳性表达率分别为78.04%(32/41)和28%(7/25),两者比较差异有统计学意义(P<0.05).相关性检验提示HIF-1α和EphA2在食管鳞状细胞癌中表达呈正相关性(r=0.5654,χ~2=13.11,P<0.05).③ Western印迹结果显示在食管鳞状细胞癌细胞株Eca109和TE13中,EphA2表达随HIF-1α的沉默而受抑制.结论 HIF-1α与EphA2在食管鳞状细胞癌组织中呈高表达,且二者表达呈正相关;EphA2表达受HIF-1α的调控,可能为HIF-1α的靶基因.     

HIF-1α induces VE-cadherin expression and modulates vasculogenic mimicry in esophageal carcinoma cells

AIM: To investigate whether hypoxia inducible factor (HIF)-1α modulates vasculogenic mimicry (VM) by upregulating VE-cadherin expression in esophageal squamous cell carcinoma (ESCC).METHODS: Esophageal squamous cancer cell lines Eca109 and TE13 were transfected with plasmids harboring small interfering RNAs targeting HIF-1α or VE-cadherin. The proliferation and invasion of esophageal carcinoma cells were detected by MTT and Transwell migration assays. The formation of tubular networks of cells was analyzed by 3D culture in vitro. BALB/c nude mice were used to observe xenograft tumor formation. The relationship between the expression of HIF-1α and VE-cadherin, ephrinA2 (EphA2) and laminin5γ2 (LN5γ2) was measured by Western blot and real-time polymerase chain reaction.RESULTS: Knockdown of HIF-1α inhibited cell proliferation (32.3% ± 6.1% for Eca109 cells and 38.6% ± 6.8% for TE13 cells, P < 0.05). Both Eca109 and TE13 cells formed typical tubular networks. The number of tubular networks markedly decreased when HIF-1α or VE-cadherin was knocked down. Expression of VE-cadherin, EphA2 and LN5γ2 was dramatically inhibited, but the expression of matrix metalloproteinase 2 had no obvious change in HIF-1α-silenced cells. Knockdown of VE-cadherin significantly decreased expression of both EphA2 and LN5γ2 (P < 0.05), while HIF-1α expression was unchanged. The time for xenograft tumor formation was 6 ± 1.2 d for Eca109 cells and Eca109 cells transfected with HIF-1α Neo control short hairpin RNA (shRNA) vector, and 8.4 ± 2.1 d for Eca109 cells transfected with an shRNA against HIF-1α. Knockdown of HIF-1α inhibited vasculogenic mimicry (VM) and tumorigenicity in vivo.CONCLUSION: HIF-1α may modulate VM in ESCC by regulating VE-cadherin expression, which affects VM formation through EphA2 and LN5γ2.     

JNK MAPK信号通路在食管癌细胞系Eca-109细胞中的作用机制

目的探讨c-jun氨基末端激酶1/2（c-jun N-teuninal kinase,JNK 1/2）信号通路在食管癌细胞系Eca-109细胞中的作用。方法体外培养Eca-109细胞,以特异性JNK信号转导通路抑制剂SP600125处理Eca-109细胞;RT-PCR的方法检测JNK1和JNK2基因的表达,Western blot法检测JNK和p-JNK蛋白的表达,MTT（3-（4,5-Dimethylthiazol-2-yl）-2,5-di-phenyltetrazolium bromide）法检测细胞增殖,流式细胞术检测细胞凋亡。结果 Eca-109细胞经SP600125分别处理24h和48 h后,分别与对照组比较,JNK1 mRNA的表达无统计学差异（均P〉0.05）,JNK2 mRNA的表达也无统计学差异（均P〉0.05）,但活化的JNK即P-JNK1/2蛋白的表达显著减少,细胞的增殖显著被抑制,细胞的凋亡率有统计学差异（均P〈0.05）。结论 JNK信号通路可能在Eca-109细胞的发生发展中发挥重要作用。     

Down-regulation of Bcl-XL by RNA interference suppresses cell growth and induces apoptosis in human esophageal cancer cells

INTRODUCTION Esophageal cancer is one of the most common malignant tumors of mankind. About 300 000 people died of esophageal cancer each year in the world. The incidence and mortality of esophageal cancer are unusually high in China, especially in the ar…     

腺病毒介导RA538及反义c-myc在不同细胞系中作用及其机制

目的比较重组RA538,反义c-myc及LacZ腺病毒(adenovirus,AV)对不同靶细胞的转染效率、生物学特性并探讨其作用的分子机制.方法以人胃癌细胞(SGC7901)、食管癌细胞(EC109)及人胚肺二倍体细胞(2BS)系为靶细胞,采用LacZ基因转染X-gal染色、形态学观察、MTT,RT-PCR等方法,研究重组RA538,反义c-myc及LacZ AV对上述细胞的转染效率,生物学作用及其分子机制.结果 AV-LacZ进行重组腺病毒转导效率检测显示其对SGC7901,2BS细胞具有很高的转导效率,对EC109细胞转导效率较低.AV-RA538及AV-ASc-myc对SGC7901细胞能产生明显的生长抑制效应并诱导凋亡,其生长抑制率分别为76.3%和44.1%.AV-RA538及AV-ASc-myc对SGC7901细胞内源性c-myc,bcl-2基因的表达具有抑制作用.AV-RA538及AV-ASc-myc对EC109细胞及2BS细胞无明显的生长抑制及凋亡诱导作用,AV-RA538对EC109及2BS细胞中内源性c-myc,bcl-2基因的表达无调节作用.结论 AV载体转导效率很高,能实现目的基因在转导细胞中的高水平表达,但对不同靶细胞的转染效率存在差别.AV-RA538,AV-ASc-myc对SGC7901的生长抑制及凋亡诱导作用可能是通过AV的高效转导及抑制c-myc,bcl-2的表达而实现的.AV-RA538,AV-ASc-myc对食管癌、2BS细胞系无类似作用可能与其对上述细胞的转导的作用及内源性基因表达的作用有关.     

腺病毒介导的凋亡素、内皮抑素双基因对食管癌的实验研究

目的探讨携带有凋亡素(vp3、Apoptin)、内皮抑素(Endostatin)双基因的重组腺病毒载体在食管癌等多种肿瘤细胞内的表达情况及致凋亡作用,为进一步的食管癌治疗应用研究打下基础。方法将已纯化的携带凋亡素和内皮抑素基因的腺病毒Ad-vp3-IRES-sEndo-His感染食管癌细胞Eca-109、小鼠肝癌细胞Hepa1-6、结肠癌细胞LoVo提取各种细胞RNA,针对凋亡素、内皮抑素基因的表达进行RT-PCR检测,同时对感染腺病毒Ad-vp3-IRES-sEndo-His、Ad-vp3的食管癌细胞通过流式细胞仪、Hoechst33258染色等方式进行细胞凋亡率的检测。结果 RT-PCR检测显示被感染的多种肿瘤细胞均可表达凋亡素、内皮抑素基因的mRNA,Ho-echst33258染色显示被Ad-vp3-IRES-sEndo-His感染的食管癌细胞出现凋亡形态学改变,用流式细胞仪测定时段最高凋亡率达47.7%,与对照组相比具有统计学意义(P<0.05)。结论携带凋亡素及内皮抑素双基因的腺病毒载体能在多种肿瘤细胞中表达,感染食管癌细胞后,能有效诱导其凋亡且其致凋亡率高于仅携带凋亡素的单基因腺病毒载体。