Contragestazol (DL111-IT) inhibits proliferation of human androgen-independent prostate cancer cell line PC3 in vitro and in vivo

Aim： To evaluate the antiproliferative activity of contragestazol （DL111-IT） on the human prostate cancer cell line PC3 in vitro and in vivo and to elucidate its potential molecular mechanisms. Methods： The cell killing ability of DL111-IT was measured by the 3-（4,5-dimethylthia-zol,2-yl）-2,5-diphenyltetrazolium bromide （MTT） reagent assay method and the tumor xenograft model. The cell cycle was analyzed by flow cytometry and protein expression, including retinoblastoma （pRb）, cyclin-dependent kinase 4 （CDK4） and cyclin D 1, was detected by Western blotting. Results： DL111-IT exhibited high efficiency on cell growth inhibition of the human androgen-independent prostate cancer cell line PC3. The drug concentration that yielded 50 % cell inhibition （IC50 value） was 9.9 mg/mL. In the PC3 tumor xenograft study, DL111-IT （1.25 mg/kg-20.0 mg/kg） given once a day for 10 days significantly inhibited tumor growth, with the inhibition rate ranging from 21% to 50 %. Flow cytometric analysis indicated that DL111-IT could cause GI arrest in the PC3 cell line, but not apoptosis. DL111-IT enhanced pRb expression and down-regulated CDK4 and cyclin D 1 expression, suggesting that cell cycle regulation might contribute to the anticancer property of DL 111- IT. Conclusion： DL111-1T inhibits the proliferation of human androgen-independent prostate cancer cell line PC3 in vitro and in vivo by a cell cycle regulation pathway.

CYTOGENETIC STUDY ON A NEW EPITHELIAL CELL LINE, HNE-1,DERIVED FROM NASOPHARYNGEAL CARCINOMA

The cytogenetics of HNE- 1 cell line derived from the biopsy of nasopharyngeal carcinoma of a 27- year- old Chinese male has been investigated by chromosomal banding technique. A karyotypic characterization of subteraploid and a modal number of 74 - 77 have been revealed in this cell line. All cells contained a series of non- random chromosomal rearrangements. 18 of them, including 5 isochromosomes. were present in all metaphases and 3 of them in a few one. These findings indicated that the severe DNA damage and increase of gene copies may be occurred in genome of HNE- 1 cells.

TGF-β1/SMAD SIGNALING PATHWAY MEDIATES p53-DEPENDENT APOPTOSIS IN HEPATOMA CELL LINES

Objective To determine whether transforming growth factor betal (TGF-β1)/Smad signaling pathway mediates p53-dependent apoptosis in hepatoma cell lines.Methods Three human hepatic carcinoma cell lines, HepG2, Huh-7, and Hep3B, were used in this study.TGF-β1-induced apoptosis in hepatic carcinoma cell lines was analyzed using TUNEL assay.For identifying the mechanism of apoptosis induced by TGF-β1, cell lines were transfected with a TGF-β1-inducible luciferase reportor plasmid containing Smad4 binding elements.After transfection, cells were treated with TGF-β1, then assayed for luciferase activity.Results The apoptosis rate of HepG2 cell lines (48.51%± 8.21%) was significantly higher than control ( 12.72%±2.18%, P<0.05).But TGF-β1 was not able to induce apoptosis of Huh-7 and Hep3B cell lines.The relative luciferase activity of TGF-β1-treated HepG2 cell lines (4.38) was significantly higher than control (1.00, P< 0.05).But the relative luciferase activity of TGF-β1-treated Huh-7 and Hep3B cell lines less increased compared with control.Conclusions HepG2 cells seem to be highly susceptible to TGF-β1-induced apoptosis compared with Hep3B and Huh-7 cell lines.Smad4 is a central mediator of TGF-β1 signaling transdution pathway.TGF-β1/Smad signaling pathway might mediate p53-dependent apoptosis in hepatoma cell lines.

Effects of Low Concentrations of Di-(2-ethylhexyl) and Mono-(2-ethylhexyl) Phthalate on Steroidogenesis Pathways and Apoptosis in the Murine Leydig Tumor Cell Line MLTC-1

The aim of this study was to evaluate the effects of low concentrations of DEHP and MEHP on steroidogenesis in a murine Leydig tumor cell line （MLTC-1） in vitro. The result of flow cytometry analysis revealed that the proportion of apoptotic cells was significantly increased after the exposure to DEHP. All three genes （P450scc, P450c17, and 38HSD） under study showed an increased expression following exposure to DEHP or MEHP, although some insignificant inhibitory effects appeared in the 10μmol/L treatment group as compared with the controls. It was also found that DEHP or MEHP stimulated INSL3 mRNA and protein especially in the 0.001 μmol/L treatment group. Testosterone secretions were stimulated after the exposure to DEHP or MEHP. Alterations of steroidogenic enzymes and INSL3 in MLTC-1 cells might be involved in the biphasic effects of DEHP/MEHP on androgen production.

Inhibitory effect of parvovirus H-1 on the formation of colonies of human hepatoma cell line in vitro and its tumors in nude mice

The inhibitory effect of parvovirus H-1 on the colonyforming ability in vitro of QGY-7703, a cultured human hepatoma cell line, and on the formation and growth of its tumors in nude mice was studied. With higher multiplicity of infection (MOI) of H-1 given, survival of the QGY-7703 cells was found to be decreased. H-1 DNA amplification level at 30 h postinfection(p.i.) was detected to be 7.4 times higher than that at 2 h by dispersed cells assay, while the cells were delayed to enter into S phase.Plaques were formed in the indicator cells (new-born human kidney cell line, NBK) by progeny H-1 virus particles released from the infected QGY-7703 cells by infectious cell center assay. The formation of tumors in nude mice by QGY-7703 cells which were injected s c at 2 h postinfection was observed to be prevented in 2 groups with given MOI 25 and 50. The tumor growth of MOI 10 group occurred at a lower exponential rate than that of control,after a 20 d latent period. It was evident that parvovirus H-1 exhibited a direct inhibitory effect on the formation and growth of human hepatoma cells in vivo as well as in vitro.

Apoptotic Sensitivity to Irradiation Increased after Transfection of chk1 Antisense Chain to HL-60 Cell Line

Summary： The HL-60 cells were transfected with chkl antisense and sense chain, and 24 h later subjected to irradiation. Twenty-four h after irradiation, the changes in the chk1 protein expression was assayed by Western blot, and the cell cycles and apoptosis rate detected by FCM. The irradiated apoptosis sensitivity was increased by antisense blocking of chk1 gene in HL-60 cell line with the apoptosis rate being 26.31 %, significantly higher than that by the sense blocking （10.34 %, 0. 025〈P〈0.05）. In HL-60 cells transfected with chkl antisense chain, the G2/M phase arrest was attenua：ted and the cells in G2/M phase were accounted for 38.42 %, significantly lower than those of the cells transfected with chkl sense chain （54.64 %, 0. 005〈P〈0.01）. It was concluded that antisense blocking of chk1 gene could increase the apoptosis sensitivity to irradiation.

Enhancement of Virus Replication in An Influenza A Virus NS1-Expresssing 293 Cell Line

The nonstructural protein 1 （NS1） of influenza A virus, which is absent from the viral particle, but highly expressed in infected cells, strongly antagonizes the interferon （IFN）-mediated antiviral response. We engineered an NS1-expressing 293 （293-NS1） cell line with no response to IFN stimulation. Compared with the parental 293 cells,

In Vivo Animal Model Evaluation of a Powerful Oral Nanomedicine for Treating Breast Cancer in BALB/c Mice Using 4T1 Cell Lines without Chemotherapy

Nanopharmaceuticals containing quantum dot nanoparticles (Q-Dot NPs) for treating serious cancers such as breast cancer have made fantastic proposals. In this study, ZnO quantum dot NPs are formulated via ZnO@PVP nanopolymer as co-assistants coordinating with efficacious suitable wetting agents, PEG-binding compound, and W/O emulsifier for producing eco-friendly water-based nanodrug. Several characterization techniques containing SEM, TEM, FTIR, photoluminescence, zeta potential, and UV-Vis absorption were employed for ZnO Q-Dot NPs in nanodrug. This work aims to investigate the anti-tumor effects of such nanomedicine on the 4T1 breast cancer cell line in BALB/c mice, being elaborated through intraperitoneal, injection (IVP) and oral therapy. The impressive findings showed that ZnO nanodrug caused changes in blood factors, having the most effectiveness at 40 μg/ml concentration after two weeks of oral treatments. The significant increase in white blood cells (WBC) neutrophils and meaningful decreases in lymphocytes and especially cholesterol were powerful simultaneous impacts, successfully treating malignant breast cancer masses. In this significant animal model research for breast cancer, the sick mice recovered entirely and even had a safe space to mate. Histopathological results showed no evidence of breast tumor formation or metastasis in the group treated with nanodrug and their children. This nanomedicine has a therapeutic effect, and is ready to be applied for treating volunteer breast cancer patients. However, its prevention (inhibitory) effect can also be analyzed and added to current data in future studies.

Potential roles of EZH2, Bmi-1 and mi R-203 in cell proliferation and invasion in hepatocellular carcinoma cell line Hep3B

AIM: To investigate the potential roles of enhancer of zeste homolog2(EZH2), Bmi-1 and mi R-203 in cell proliferation and invasion in hepatocellular carcinoma(HCC) cell line Hep3 B.METHODS: A total of 73 patients who underwent surgical resection at Fuzong Clinical Medical College of Fujian Medical University were enrolled in this study. Hep3 B cells were cultivated in RPMI 1640 medium supplemented with 10% fetal bovine serum at 37?℃. Vectors that containing c DNA of the EZH2 gene or mi R-203 targeted sh RNA plasmid were constructed, and then transfected into Hep3 B cells. The m RNA expression of mi R-203, EZH2, and Bmi-1 was analyzed using quantitative real-time polymerase chain reaction analysis, and the protein levels of EZH2 and Bmi-1 were detected by Western blot analysis. Effect of EZH2 or mi R-203 on cell proliferation was observed by methyl thiazolyl tetrazolium assay, and cell apoptosis was assessed using flow cytometry. Besides, effect of EZH2 or mi R-203 on tumor cell invasion was detected using Transwell assay.RESULTS: The m RNA levels of EZH2 and Bmi-1 in HCC tissues and in Hep3 B cells were significantly higher compared with those in normal samples(P < 0.01), while mi R-203 level was significantly lower in HCC tissues(P < 0.01). Hep3 B cells transfected with EZH2-sh RNA or mi R-203-sh RNA showed lower expression levels of EZH2 and Bmi-1(P < 0.05). Compared with controls, Hep3 B cells transfected with EZH2-sh RNA had relative slow cell proliferation, indicating that low expression of EZH2 and Bmi-1 and overexpression of mi R-203 could inhibit Hep3 B cell proliferation(P < 0.05). The average apoptosis rate of Hep3 B cells transfected with EZH2-sh RNA vector was about 18.631%, while that of Hep3 B cells transfected with sh RNA vector was about 5.33%, suggesting that EZH2 was down-regulated by transfecting with EZH2-sh RNA, and the down-regulated EZH2 contributed to the cell apoptosis. Low expression of EZH2 and Bmi-1 and overexpression of mi R-203 could reduce Hep3 B cell invasion(P < 0.05).CONCLUSION: Our study suggests that EZH2 and Bmi-1 are up-regulated while mi R-203 is downregulated in Hep3 B cells. Mi R-203 may contribute to the metastasis and enhance apoptosis of HCC cells by regulating EZH2 and Bmi-1. Our study may provide a theoretical basis for metastasis of HCC and targeted therapy of HCC.

MiR-25-3p attenuates the proliferation of tongue squamous cell carcinoma cell line Tca8113

Objective:To investigate the effects of miR-25-3p on the occurrence,development and proliferation of tongue squamous cell carcinoma cells.Methods:To establish tongue squamous cell carcinoma cell line Tca8113 that stably and highly express miR-25-3p using recombinant reiroviral vector-mediated gene transfer method.The proliferation of transfected Tca8113 was detected by thiazolyl blue tetrazolium bromide(MTT)and cell colony formation assays.eyclnD1,p21^(cipt)and p27^(kipt)mRNA expressions in the transfected Tca-8113 were detected by quantitative PCR.cyclinD1,p21^(cipt),p27^(kipt),AKT,p-AKT,FOXOt and p-FOX01 expressions in the transfected Tca8113 were detected by western blot analysis.In addition,miR-25-3p expression in the tongue squamous cell carcinoma cell line and tissue specimen was also detected by quantitative PCR.Results:Quantitative PCR showed that mitt-25-3p expression in the tongue squamous cell carcinoma cell lines and tissue specimen was significantly lower than that in the adjacent tissue.MTT and cell colony formation assays showed that after miR-25-3p overexpression,the proliferation of transfected Tca8113 was obviously attenuated.Western blot analysis and quantitative PCR showed that after miR-25-3p overexpression.p21^(cipt)and p27^(kipt)expressions were upregulated,while cyclinD1,AKT,FOXO1 expressions were downregulated,and AKT and FOXO1 phosphorylation was inactivated in the transfected Tca8113 cells.Conclusions:MiR-25-3p inhibited the proliferation of tongue squamous cell carcinoma cells and regulated cell cycle-related protein expression,playing an important role in the occurrence and development of squamous cell carcinoma of the tongue.

藤黄酸对MUTZ-1细胞生长抑制作用及其机理研究

本研究旨在探讨藤黄酸对高危组骨髓增生异常综合征(MDS)细胞的生长抑制作用及其机制。以人MDS-RAEB细胞株MUTZ-1细胞为研究对象,采用MTT法测定增殖抑制率,流式细胞术检测细胞凋亡及细胞周期变化,用RT-PCR检测bax/bcl-2基因表达。结果表明,藤黄酸对MUTZ-1细胞有生长抑制作用,在0.2-0.8μg/ml浓度范围内随着药物浓度的增加MUTZ-1细胞的增殖抑制率增高;流式细胞学检测发现,藤黄酸浓度0、0.4、0.6、0.8μg/ml引起的MUTZ-1凋亡率分别为(5±0.5)%、(13±0.5)%、(37±0.7)%和(56±0.6)%,而且凋亡率随着药物浓度增加而增加(p<0.05)。bcl-2基因表达程度随藤黄酸剂量增加而减弱,而baxmRNA表达无明显变化。结论:藤黄酸通过诱导MUTZ-1细胞凋亡、下调bcl-2基因表达而抑制该细胞生长,这可能是藤黄酸抗肿瘤的主要机制之一。

2-甲氧基雌二醇诱导骨髓增生异常综合征MUTZ-1细胞凋亡机制的研究(英文)

为了研究2-甲氧基雌二醇(methoxyestradiol,2-ME)诱导骨髓增生异常综合征-难治性贫血伴原始细胞增多型(MDS-RAEB)细胞株MUTZ-1细胞凋亡的机制,将不同浓度的2-甲氧基雌二醇分别与MUTZ-1细胞在体外培养,同时设二甲亚砜和空白对照组。采用四甲基偶氮唑蓝(MTT)比色法测定2-ME对MUTZ-1细胞的生长抑制率,瑞氏-姬姆萨染色后观察2-ME引起细胞的形态学改变,流式细胞术分析细胞周期和凋亡率的变化,贝克曼全自动生化分析仪(synchron clinical system LX20)检测培养上清液中乳酸脱氢酶(lactate dehydrogenase,LD)的变化,DNA凝胶电泳验证2-ME诱导的细胞凋亡。结果表明:2-ME对MUTZ-1细胞的增殖具有明显的抑制作用,该细胞凋亡率明显升高,并呈现时间和剂量依赖性,经统计学处理与对照组相比较有显著性差异(P<0.05)。4μmol/L2-ME作用MUTZ-1细胞12小时后,细胞呈现典型的凋亡细胞形态特征;2-ME作用24小时后MUTZ-1细胞出现G2/M期阻滞;培养上清液中LD含量与对照组相比明显升高,差异具有显著性(P<0.05);4μmol/L2-ME作用MUTZ-1细胞48小时后,DNA凝胶电泳可见明显的DNA梯形条带。结论:2-ME对骨髓增生异常综合征细胞株MUTZ-1有较强的抗肿瘤效应,可能与细胞G2/M期阻滞引起的细胞凋亡有关;2-ME是一种有发展潜力的治疗骨髓异常综合征的药物。

丙戊酸钠诱导骨髓增生异常综合征细胞株MUTZ-1凋亡的实验研究

为了探讨丙戊酸钠(sodium valproate,VPA)对骨髓增生异常综合征细胞株MUTZ-1的生长抑制及诱导凋亡作用,采用四甲基偶氮唑蓝(MTT)比色法检测VPA对细胞生长的抑制作用;采用光学显微镜和电子显微镜观察VPA作用后细胞形态的变化;应用流式细胞术(FCM)检测不同浓度VPA作用后细胞凋亡的比例和细胞周期分布的变化。结果显示:VPA对MUTZ-1细胞的生长抑制作用呈现时间和剂量依赖性;经4mmol/LVPA处理MUTZ-1细胞72小时后,细胞呈现典型的凋亡形态特征,光学显微镜下可见凋亡细胞胞体固缩、核固缩、核碎裂及凋亡小体;透射电子显微镜下可见凋亡细胞核染色质边集、胞浆浓缩、密度增加,胞浆内大小不规则的染色质团块;流式细胞术结果表明,细胞凋亡率随着VPA浓度的增加而逐步增高,G0/G1期细胞比例随着VPA浓度的增加而逐渐增多,S期细胞比例逐渐减低,细胞被阻滞在G0/G1期。结论:VPA通过G0/G1期阻滞诱导MUTZ-1细胞凋亡,从而抑制MUTZ-1细胞增殖。

维生素K_2诱导人骨髓增生异常综合征细胞株MUTZ-1细胞凋亡机制的研究

为了研究维生素K2(VK2)诱导人骨髓增生异常综合征(MDS)细胞株MUTZ-1细胞凋亡的作用机制,采用流式细胞术Annexin-VFITC/PI双染分析细胞凋亡率和PI染色分析细胞周期的改变,用RT-PCR技术检测抗凋亡基因bcl-2、survivin和促凋亡基因bax的表达,用发光比色法检测caspase-3活性。研究结果显示:细胞的凋亡率随着VK2浓度的增加和作用时间的延长逐渐增高并呈明显的时间浓度依赖性(P<0.05),且随着药物浓度的增加和作用时间的延长S期和G2期细胞逐渐减少(P<0.05),G0/G1期细胞逐渐增多(P<0.01),细胞被阻滞在G0/G1期,并且在G0/G1期前出现明显的亚G1峰,即凋亡峰;抗凋亡基因bcl-2、survivin的表达随着VK2浓度的增高明显下调(P<0.05),而促凋亡基因bax表达无明显变化(P>0.05);caspase-3的活性随着VK2浓度的增加和作用时间的延长而逐渐增强。结论:VK2主要是通过激活caspase-3途径诱导MUTZ-1细胞发生凋亡,同时抗凋亡基因bcl-2、survivin在细胞凋亡过程中也起重要作用。

2-甲氧基雌二醇对MUTZ-1细胞内活性氧和线粒体膜电位的影响

目的探讨在2-甲氧基雌二醇（2-ME）诱导骨髓增生异常综合征（myelodysplastic syndrome，MDS）MUTZ-1细胞凋亡中活性氧（ROS）和线粒体膜电位（△ψm）的作用及其作用机制。方法MUTZ-1细胞与不同浓度2-ME共育，FCM分析荧光探针DCFH-DA标记后细胞内ROS和荧光探针JC-1标记后细胞△ψm的变化。加入抗氧化剂过氧化氢酶（CAT）后，MUTZ-1细胞内相应指标的变化。结果经1-4μmol／L 2-ME作用MUTZ-1细胞12h，与对照组相比，细胞内ROS升高（F=102．56，P〈0.05）和细胞△ψm下调（F=108．02，P〈0．05），且MUTZ-1细胞△ψm下降与细胞内ROS升高成正相关（r=0．981，P=0．019）。CAT能够明显抑制2-ME诱导MUTZ-1细胞内ROS升高（F=68．26，P〈0．01）和细胞△ψm下调（F=55．29，P〈0.01）。结论2-ME诱导MUTZ-1细胞凋亡，可能与2-ME刺激细胞内ROS积聚过多、损伤线粒体结构的完整性以及降低细胞线粒体膜电位有关。

Expression of C-Terminal Modified Serine Palmitoyltransferase-1 Alters Chemosensitivity of Inflammation-Associated Human Cancer Cell Lines

Background: The human serine palmitoyltransferase-1, SPTLC1, subunit is emerging as a stress responsive protein with putative role in modulating cellular stress response behavior. When compared to the parental cell line, recombinant Glioma cells expressing C-terminal modified SPTLC1 are found to show resistance to the cytotoxic effect of polycyclic hydrocarbons, PHs, including the environmental contaminant 3-methylcholanthrene. This novel functional association of SPTLC1 expression with proliferative capacity is thought to be due, in part, to its ability for crosstalk with protein regulators of different biological processes. Whether the effect of SPTLC1 on sensitivity to PHs extends to therapeutic drugs and the progression of the malignant phenotype is of research interest. Methods: In the current study, sub-cellular localization was by immunostaining for SPTLC1 in untreated and chemical treated cells and detection with confocal microscopy. The effect expressing C-terminal modified SPTLC1, in cancer cell lines of the inflammation-associated type, has on chemosensitivity and gene expression was also assessed. Parent Glioma LN18 and SKN-SH cells and their SPTLC1 recombinants were each treated with Glutamate, an excitatory neurotransmitter that can participate in both neuronal and excitotoxic signaling. In addition to the Glioma and SKN-SH cells, the PC3 prostate cancer and 647V bladder cancer cell lines were also treated with Celecoxib, a potent inhibitor of cyclooxygenase 2, COX-2, and an anti-inflammatory drug recently found to have anti-neoplastic activity against several malignancies. Results: Confocal microscopy revealed that Celecoxib mediates both rapid and enhanced redistribution of SPTLC1 and COX-2, to focal adhesion sites. In cell viability assay, SPTLC1 recombinant cells exhibited differential but dose-dependent resistance to excitotoxic levels of Glutamate. Drug co-treatment with a non-lethal dose of the potent kinase inhibitor, Sulfasalazine, increased the anti-proliferation effect of Celecoxib in a dose-dependent manner for all the cell lines tested. Conclusions: The effect of SPTLC1 expression on cellular chemosensitivity seen in the present study further highlights possible role of a C-terminal modified SPTLC1 variant in the biologic modulation of cellular behavior in response to therapeutic anticancer drugs.

维生素K_2对人骨髓增生异常综合征细胞株MUTZ-1增殖抑制作用的实验研究

目的：研究维生素K（VK2）对人骨髓增生异常综合征细胞株MUTZ-1的生长抑制作用。方法：采用光镜或电镜技术观察VK2作用于MUTZ-1细胞株后细胞形态和超微结构的改变；应用四甲基偶氮唑蓝（MTT）法检测细胞的增殖抑制作用。结果：VK2作用于MUTZ-172h后呈现典型凋亡细胞的形态学改变，且随着VK2浓度的增加和作用时间的延长凋亡细胞所占的百分比增高；MTT结果显示10μmol·L^-1及以上浓度的VK2处理MUTZ-1细胞株后细胞生长明显受抑，并呈浓度依赖性，与对照组比有显著性差异（P〈0．05）；且随着VK2作用。时间的延长细胞凋亡率也逐渐增高，且呈明显的时问依赖性（P〈0．05）。5μmol·L^-1的VK2有促MUTZ-1细胞株增生的趋势，但与对照组相比无显著性差异（P〉0．05）。结论：低浓度VK2（5μmol·L^-1）对MUTZ-1细胞株有促增殖趋势；较高浓度的VK2（10～40μmol·L^-1）主要是通过诱导MUTZ-1细胞凋亡而抑制其增殖。

Establishment and characterization of a new cell line derived from human colorectal laterally spreading tumor

AIM:To study the molecular mechanism of laterally spreading tumor (LST), a cell line [Laterally Spreading Tumor-Rectum 1 (LST-R1)] was derived and the characteristics of this cell line were investigated. METHODS:A new cell line (LST-R1) originated from laterally spreading tumor was established. Properties of the cell line were characterized using scanning and transmission electron microscopy, immunohistochemistry method, cytogenetic analysis and nude mice xenograft experiments. In vitro invasion assay, cDNA microarray and Western blotting were used to compare the difference between the LST-R1 and other colorectal cancer cell lines derived from prudent colon cancer. RESULTS:Our study demonstrated that both epithelial special antigen (ESA) and cytokeratin-20 (CK20) were expressed in LST-R1. The cells presented microvilli and tight junction with large nuclei. The karyotypic analysis showed hyperdiploid features with structural chromosome aberrations. The in vivo tumorigenicity was also demonstrated in nude mice xenograft experiments. The invasion assay suggested this cell line has a higher invasive ability. cDNA microarray and Western blotting show the loss of the expression of E-cadherin in LST-R1 cells.CONCLUSION:We established and characterized a colorectal cancer cell line, LST-R1 and LST-R1 has an obvious malignant tendency, which maybe partially attributed to the changes of the expression of some adhesion molecules, such as E-cadherin. It is also a versatile tool for exploring the original and progressive mechanisms of laterally spreading tumor and the early colon cancer genesis.

Establishment of an avian leukosis virus subgroup A-resistant cell line

Rapid diagnostic methods for classifying avian leukosis subgroups in the field were needed for routine, large-scale screening. As a first step in method development, we inserted the avian leukosis virus subgroup A （ALV-A） env gene into plasmid pcDNA3.1/Zeo （＋） and used this construct to transfect DF-1 cells. Zeocin-resistant cells were obtained after 2 weeks of zeocin selection. Then, the cells were analyzed using PCR, immunofluorescence, and Western blot for expression of the envA-encoded envelope protein after 30 serial passages. The DF-1/A cell line was completely resistant to 104 TCIDso/0.1 mL （50% tissue culture infective dose）ALV-A and was partially resistant to 10~ TCIDs0/0.1 mL ALV-A viral particles. By comparing the DF-1/A and DF-1 cell lines, an ALV-A isolate was identified using a gag-specific ELISAfor capsid protein p27. Thus, we established a DF-1/A cell line that was resistant to ALV-A infection. This cell line will be useful as a diagnostic tool.

Establishment and characterization of a rat pancreatic stellate cell line by spontaneous immortalization

AIM: Activated pancreatic stellate cells (PSCs) have been implicated in the pathogenesis of pancreatic fibrosis and inflammation. Primary PSCs can be subcultured only several times because of their limited growth potential. A continuous cell line may therefore be valuable in studying molecular mechanisms of these pancreatic disorders. The aim of this study was to establish a cell line of rat PSCs by spontaneous immortalization.METHODS: PSCs were isolated from the pancreas of male Wistar rats, and conventional subcultivation was performed repeatedly. Telomerase activity was measured using the telomere repeat amplification protocol. Activation of transcription factors was assessed by electrophoretic mobility shift assay.Activation of mitogen-activated protein (MAP) kinases was examined by Western blotting using anti-phosphospecific antibodies. Expression of cytokine-induced neutrophil chemoattractant-1 was determined by enzyme immunoassay.RESULTS: Conventional subcultivation yielded actively growing cells. One clone was obtained after limiting dilution,and designated as SIPS. This cell line has been passaged repeatedly more than 2 years, and is thus likely immortalized.SIPS cells retained morphological characteristics of primary,culture-activated PSCs. SIPS expressed α-smooth muscle actin, glial acidic fibrillary protein, vimentin, desmin, type Ⅰ collagen, fibronectin, and prolyl hydroxylases. Telomerase activity and p53 expression were negative. Proliferation of SIPS cells was serum-dependent, and stimulated with platelet-derived growth factor-BB through the activation of extracellular signal-regulated kinase. Interleukin-1β activated nuclear factor-κB, activator protein-1, and MAP kinases.Interleukin-1β induced cytokine-induced neutrophil chemoattractant-1 expression through the activation of nuclear factor-κB and MAP kinases.CONCLUSION: SIPS cells can be useful for in vitro studies of cell biology and signal transduction of PSCs.